The Doha Municipality is celebrating its 60th anniversary, and Minister of Municipality HE Dr. Abdullah bin Abdulaziz bin Turki Al Subaie has expressed his great delight.
He claimed that during the course of its lengthy existence since being founded on January 1, 1963, as the “Qatar Municipality,” the Municipality has accomplished some very outstanding things.
In order to ensure the upgrading and improvement of the varied municipal services system and the promotion of urban development, the Minister stated that this occasion serves as a motivation for Doha Municipality and all of its employees to continue working and persevering as well as to double down on joint efforts with all governmental and non-governmental sectors. The Minister of Municipality emphasised that Doha City, the front and capital of the State, has been a significant location for holding various local, regional, and international events during the past years and since its foundation.
He said that since the award’s founding in 1983, Doha has served as the home of the Arab Cities Award’s headquarters, one of the organisations of the Arab Towns Organization.


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text:
|Publication number||US6504779 B2|
|Application number||US 09/855,118|
|Publication date||Jan 7, 2003|
|Filing date||May 14, 2001|
|Priority date||May 14, 2001|
|Also published as||CN1385859A, CN100474439C, EP1260988A2, EP1260988A3, US20020167838|
|Publication number||09855118, 855118, US 6504779 B2, US 6504779B2, US-B2-6504779, US6504779 B2, US6504779B2|
|Inventors||Frederick A. Perner|
|Original Assignee||Hewlett-Packard Company|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (2), Referenced by (24), Classifications (20), Legal Events (8)|
|External Links: USPTO, USPTO Assignment, Espacenet|
1. Field of the Invention
The present invention relates to devices for data storage and retrieval. Particularly, this invention relates to a resistive cross point memory (RXPtM) cell array, one example of which is a magnetic random access memory (MRAM), and to circuitry for sensing a resistive state of a memory cell in the array so as to sense a stored data value from the memory cell. It is conceivable that other forms of RXPtM's will be developed that are not based on MRAM use, and the methods described in this invention disclosure will apply to those also. More particularly, this invention relates to a method and apparatus for testing for acceptable calibration of a sense amplifier which is utilized in sensing the resistance value of a memory cell and sensing a stored data value from a memory cell, and for initiating recalibration of the sense amplifier, when needed, all without destroying data stored in the memory cell.
2. Related Technology
Magnetic Random Access Memory (“MRAM”) is a non-volatile memory that is being considered for long term data storage. A typical MRAM device includes an array of memory cells. Word lines extend along rows of the memory cells, and bit lines extend along columns of the memory cells. The memory cells are each located at a cross point of a word line and a bit line, and each memory cell includes two masses of magnetic material. One of the masses is magnetically fixed and the other is magnetically variable. A memory cell stores a bit of information as the orientation of relative magnetization of the fixed and variable materials. In other words, the magnetization of each memory cell at any given time assumes one of two stable orientations. These two stable orientations, referred to as “parallel” and “anti-parallel” magnetic orientation, represent logic values of ‘0’ and ‘1,’ for example. The resistance of a memory cell varies dependent upon whether it stores a “0” or a “1” value. That is, the resistance of a memory cell is a first value “R” if the orientation of the magnetization of the fixed magnetic material and of the variable magnetic material is parallel, and the resistance of the memory cell is increased to a second value R+ΔR if the orientation of the magnetization is anti-parallel. The orientation of the relative magnetization of a selected memory cell (and, therefore, the logic state of the memory cell) may be sensed by sensing the resistance value of the selected memory cell.
Performing sense and write operations in MRAM devices could be orders of magnitude faster than performing sense and write operations in conventional long term storage devices, such as hard drives, for example. In addition, the MRAM devices could be more compact and could consume less power than hard drives and other such conventional long term data storage devices.
However, sensing the resistance state of a single memory cell in an array (and thereby “sensing” the data value) can be unreliable. All memory cells in the array are coupled together through many parallel paths (i.e., the bit and word lines). The resistance seen at one cross point equals the resistance of the memory cell at that cross point in parallel with resistances of memory cells in the other rows and columns (again, the array of memory cells may be characterized as a cross point resistor network).
There is a need to reliably sense the resistance states of memory cells in MRAM devices.
Currently, it is known to use a sense amplifier to sense a resistance value associated with a selected memory cell of an array. However, determining when the sense amplifier has an acceptable calibration or needs to be recalibrated is conventionally performed off of the chip on which the array of memory cells is fabricated. Further, conventional methods of determining when a new sense amplifier recalibration is required and performing that recalibration, destroys data in a memory cell. In essence, calibration of such an sense amplifier is a laboratory procedure.
Further, calibration of a sense amplifier so that it can reliably perform this sense operation compensates at the same time for two aspects of the RXPtM array. These two aspects may be considered as “global” and “environmental.” That is, the sense amplifier is compensated or calibrated for global factors of the memory cell array that are constant over time. These global factors include such influences as process and geometry variations (i.e., asymmetries in the circuit design and fabrication non-uniformity resulting in threshold voltage variations and resistance and capacitance variations, for example) that occur during fabrication of the memory cell array. At the same time, the environmental factors then existing for the RXPtM array are compensated for. However, compensation for the global factors which are constant over time does not address needed compensations for environmental parameters which change over time. These environmental parameters include such factors as operating temperature of the RXPtM array, and power supply voltage variations.
Thus, there is a need to provide a method and apparatus to determine when recalibration of sense amplifier offset (i.e., calibration) values is necessary for reliably sensing stored data values in a RXPtM.
Further, there is a need for providing of such a method and apparatus to determine when recalibration of a sense amplifier is needed before data is lost because of an amplifier “out of calibration” condition.
Also, there is a need for such a sense amplifier recalibration to be performed without loss of data stored in a RXPtM array.
Still further, there is a need to have such a method and apparatus implemented on the same chip as the RXPtM cell array.
These needs are met by the present invention. According to one aspect of the present invention, a sense amplifier is employed to sense the resistance state of a set of RXPtM cells, and a digital value of “0” or “1” for each memory element of the set is determined by comparing individual cell sense data to an average data value using a multiple sense method. The sense method uses a “time value.” By “time value” is meant that the resistance value of an individual RXPtM cell is determined by a current-to-time conversion when an operating voltage is applied to the RXPtM cell with a sense amplifier.
The “average time value” (ATV) for the set of RXPtM cells is determined, and a pair of test limit values (respectively referred to as “shorts” and “opens” values are set at preferred time values of ¼ATV, and 4ATV, for example. It will be understood that other values of the “shorts” and “opens” test limit values may be utilized. However, and importantly, any memory cell of the set which has an individual time value less than or equal to the “shorts” value, or greater than or equal to the “opens” value is labeled as inoperative, and is not utilized in determining when a recalibration of the sense amplifier is necessary. That is, a shorted memory cell or an open-circuit memory cell is not included in the set of memory cells which is utilized to determine the need for recalibration of the sense amplifiers.
Further, an additional pair of recalibration high/recalibration low (Recal Hi/Lo) limit values are determined. These Recal Hi/Lo values may preferably be determined as ½ATV and 2ATV, for example. Again, it is to be understood that other values for the Recal Hi/Lo values might be selected. However, the pair of Recal Hi/Lo values lie between the “shorts” and “opens” values, as will be understood from the explanation above.
Then, for each memory cell of the array in which data is stored, and contemporaneously with an initial “sense” operation of that memory cell, a sense amplifier is employed to sense the resistance value of the memory cell. If a “shorts” or “opens” condition is detected, then the recalibration test result is ignored. That is, a shorted or open-circuited memory cell will not trigger a recalibration. However, if a “shorts” or “opens” condition is not detected, then the results of the testing of the memory cell's resistance is compared to the Recal Hi/Lo limits. So long as the cell's resistance is indicated to be within (i.e., between) the pair of Recal Hi/Lo limits, than sensing of the memory cell proceeds, and no recalibration of the sense amplifier for that memory cell is initiated. On the other hand, if the Recal Hi/Lo limits are exceeded (i.e., meaning that the sensed cell's “time value” is either below ½ATV, or above 2ATV, but not less than ¼ATV or more than 4ATV) then sensing of the memory cell stops, data stored in the memory cell is preserved undisturbed, a sense amplifier recalibration is initiated, and the data stored in the memory cell is sensed later after completion of this sense amplifier recalibration.
Further to the above, the calibration controller is part of an Input/Output controller fabricated on the same chip along with the array of memory cells. Thus, each time a sense operation is to be performed to determine the stored value of a memory cell of the array, an on-chip amplifier test, and recalibration if necessary, takes place before the data value is sensed from the memory cell. Because the on-chip test and recalibration of the sense amplifier used to sense the resistance value (i.e., sense the data value) of a cell takes place on-chip close to the array, the time and power used to carry out this sense process is minimized. Further, the integrity of data stored in the cells of the array is maintained. This is true because data is not sensed until it is confirmed that the sense amplifier that will be sensing the resistance value of the memory cell containing the data has a proper calibration, and that a correct result will be had from the sensing operation performed on the memory cell.
Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the present invention.
FIG. 1 is a very generalized schematic illustration of an MRAM memory cell array according to the present invention;
FIGS. 2a and 2 b are illustrations of parallel and anti-parallel magnetization orientations of a typical MRAM memory cell;
FIG. 3 is an illustration of an MRAM memory cell that has been selected during a sensing step;
FIG. 4 is a more particularized illustration of a memory chip including a memory cell array, an amplifier array, and an I/O controller, all on a single chip;
FIG. 5 is a graphical illustration of time values used in testing a memory cell and associated amplifier fro proper calibration under then existing environmental conditions;
FIG. 6 illustrates a generalized schematic of a circuit that may be utilized in the methods of sensing a memory cell in a resistive cross point memory cell array;
FIG. 7 is a method flow chart illustrating a method of sensing a memory cell of a MRAM memory cell array, while contemporaneously testing for proper amplifier calibration.
The present invention is most preferably embodied in an MRAM memory device, which includes a memory cell array, a sense amplifier array, and an input/output (I/O) controller, all on a single chip. That is, the elements of the memory cell array, of the sense amplifier array, and of the I/O controller are all formed on the same chip. Further, the I/O controller includes an amplifier calibration controller, which is responsible for carrying out the amplifier recalibration evaluation process with respect to each memory cell of the array before data is sensed from that particular cell. Thus, data stored in cells of the array is never compromised or destroyed by an attempt to sense the data with a sense amplifier that is out of calibration with respect to global or environmental conditions of the RXPtM array. Environmental conditions of the RXPtM array, which change with time, are compensated for by recalibration of the sense amplifier before they can have a detrimental effect on the reliability of data retrieval from the cells of the array.
Reference is now made to FIG. 1, which schematically illustrates an MRAM device 10 including an array 12 of memory cells 14. The memory cells 14 are arranged in rows and columns of the array, with the rows extending along an x-direction and the columns extending along a y-direction. Only a relatively small number of memory cells 12 are shown in FIG. 1 in order to simplify the description of the invention. In practice, arrays of any size may be used.
Conductive traces functioning as word lines 16 extend along the x-direction in a plane of the memory cell array 10. Other conductive traces functioning as bit lines 18 extend along the y-direction in a plane of the memory cell array 10. There may be one word line 16 for each row of the array 10 and one bit line 18 for each column of the array 10. Each memory cell 14 is located at a cross point of a corresponding word line 16 and bit line 18, hence the name “resistive cross point memory” cell array, or RXPtM.
The memory cells 14 are not limited to any particular type of device. For example the memory cells 14 may be fabricated to utilize spin dependent tunneling (“SDT”) junction devices. However, the resistance value of each of the memory cells 14 is dependent upon the value (i.e., 1 or 0) of a data bit stored in the particular cell.
Further considering FIG. 1, the RXPtM cell array 10 also includes a row decode circuit 20. During sense operations, the row decode circuit 20 may apply either a constant supply voltage Vs or a ground potential to selected ones of the word lines 16. The constant supply voltage Vs may be provided by an external circuit.
The RXPtM cell array 10 further includes a sense amplifier circuit for sensing the resistance of selected memory cells 14 during sense operations, and a write circuit for orienting the magnetization of selected memory cells 14 during write operations. The sense amplifier circuit is indicated generally at 22. The write circuit is not shown in order to simplify the explanation of the present invention.
The sense amplifier circuit 22 includes a plurality of steering circuits 24 and sense amplifiers 26. Also, this circuit 22 preferably includes an analog to digital converter, including an integrator, a comparator, and a pre-settable counter (which sub-components are not individually indicated on drawing FIG. 1). Multiple bit lines 18 are connected to each steering circuit 24. Each steering circuit 24 includes a set of switches that connect each bit line 18 to either a source of operating potential or to a sense amplifier 26. An output of the sense amplifier 26 is supplied to a data register 28, which, in turn, is coupled via an I/O controller circuit 30 to an output (indicated by arrowed numeral 32) of the MRAM device 10. The I/O controller 30 controls the entire MRAM device 10 (hence, the dashed box encompassing sub-parts of I/O controller 30 in FIG. 1, to be further described below), and the outputs 32 may be common to one another (i.e., via a shared data I/O port, for example).
Referring now to FIGS. 2a and 2 b, a typical SDT junction memory cell 14 includes a magnetic layer 34 of “pinned” or fixed magnetic orientation. The layer 34 has a magnetization that is oriented in the plane of the pinned layer 34, and which is fixed in a selected direction in this plane so as not to change orientation in the presence of an applied magnetic field having a magnitude within a range of interest. The SDT junction device 14 also includes a “free” layer 36 having an orientation of magnetization that is not pinned. Rather, the magnetization of the layer 36 can be selectively oriented in either of two directions both lying in the plane of the layer 36. If the magnetization of the free and pinned layers 34 and 36 are generally in the same direction, the orientation is said to be “parallel” (again, as is indicated by the arrows in FIG. 2a). If the magnetization of the free and pinned 34 and 36 layers are generally in opposite directions (viewing FIG. 2b), then the orientation is said to be “anti-parallel.” The magnetization in the free layer 36 may be selectively oriented by applying write currents to word and bit lines 16 and 18 that cross the memory cell 14.
The free and pinned layers 34 and 36 are separated by an insulating tunnel barrier 38. The insulating tunnel barrier 38 allows quantum mechanical tunneling to occur between the free and pinned layers 34 and 36. This tunneling phenomenon is electron spin dependent, making the resistance of the SDT junction device 14 a function of the relative orientations of the magnetization of the free and pinned layers 34 and 36. Again, the resistance of a SDT junction device 14 will have a first value R if the orientation of magnetization of the free and pinned layers 34 and 36 is parallel, and will have a second value R+ΔR if the magnetization of orientation is anti-parallel.
Referring to FIG. 3 a selected memory cell 14 is illustrated during a sense operation. During the write operation which stored a data value in the memory cell 14, the magnetization in the free layer 36 of the selected memory cell 14 was oriented by applying the currents to both the word line 16 and bit line 18 crossing that memory cell 14. Applying the currents to the word line 16 and bit line 18 caused the magnetization of the free layer 36 to rotate to a selected one of the parallel orientation or to the anti-parallel orientation. Thus, a resistance value (i.e., R, or R+ΔR) between the lines 16 and 18 for cell 14 is associated with the stored data value.
FIG. 4 illustrates a MRAM memory chip 40 embodying the present invention. Viewing FIG. 4 it is seen that the MRAM chip includes a substrate 42 upon which the MRAM device 10 including the array 12 of cells is formed. Also formed on this same substrate 42 is a sense amplifier array 44, which includes a plurality of sense amplifiers 26, recalling the description of FIG. 1 above. Controlling the interface of the array 44 of amplifiers 26, and the array of memory cells 12 is a global controller circuit 46. The global controller circuit 46 includes row circuits 20 and column circuits 22, and also moderates communication of data into and from the array 12 via an input/output port 48 (i.e., indicated with the double-headed arrow on FIG. 4). While the global controller circuit 46 will include circuit portions in addition to those described here, it is important to note that this global controller circuit 46 includes a calibration controller 50.
Calibration controller 50 is effective upon each command from global control circuit 46 to sense a data bit (i.e., to sense a relevant resistance value) from a memory cell of the memory cell array 12, to test the calibration of the one of the sense amplifiers of the amplifier array 44 which will effect this sensing of the selected memory cell.
Importantly, FIG. 5 depicts a time versus voltage relationship that is preferably utilized according to the present invention in order to make a determination as to whether a particular sense amplifier has a correct calibration, and if not, to initiate a calibration of the particular sense amplifier. Considering now FIGS. 5 and 7 in conjunction with one another, it is seen in FIG. 5 that a particular time value is indicated as having a value of “1” and is labeled 1AVT (average time value). The time interval indicated as 1ATV is determined by individually testing (i.e., connecting) memory cells of a selected set of representative memory cells (i.e., representative of the cells of memory cell array 12) with an integrator circuit with the selected memory cell, and a pre-charged integration capacitor, an integrator, a comparator, and a pre-settable counter. The result is that the integration capacitor is discharged over time via the integrator, and the curve of voltage difference between Vdd and the charge level on the capacitance (i.e., in volts) is represented graphically. The time interval for each of the set of memory cells is determined, and the average value of time versus voltage is indicated graphically on the graph of FIG. 5. The average value of time versus voltage is indicated on the graph of FIG. 5 as 1AVT.
Next, values of ¼AVT, of ½AVT, of 2AVT, and of 4AVT are determined. An outer pair of the time values indicated on FIG. 5 (i.e., the values of time indicated as ¼AVT and as 4AVT) are identified as values of time indicative of “shorts” and “opens,” respectively. That is, if a particular memory cell is selected, and if the time interval measured is less that ¼AVT then the memory cell is considered to be shorted and to be bad. On the other hand, if the time interval measured is greater than 4AVT, then the memory cell is considered to be open-circuited, and is also bad. Bad memory cells are not used in testing for proper calibration of the sense amplifiers of the amplifier array 44.
Again, it will be understood that other values of the “shorts” and “opens” test limit values may be utilized. However, the selected and preferred values are powers of 2, and are easily implemented digitally. Further, these selected values for the test limits have been shown by actual testing of the invention to provide very reliable operation for the MRAM chip 40.
Further, an additional pair of time intervals (i.e., ½AVT and 2AVT) are designated, and are indicated as recalibration high/recalibration low (Recal Hi/Lo) limit values. These Recal Hi/Lo values are the values within (i.e., between) which the time interval for a particular selected memory cell which is to be sensed must fall in order to indicate that the sense amplifier which will sense this memory cell has a proper calibration in view of the environmental factors then effective on the memory cell array 12. That is, the operating voltage Vdd of the MRAM chip 40 may have drifted, or the temperature of the memory cell array 12 may have changed so that the resistance of the memory cells and other circuit elements of the chip 40 is changed. The result is that if the time interval for the particular memory cell falls within the range from ½AVT to 2AVT, then the memory cell will be sensed, it is anticipated that the sensing result may be relied upon, and a recalibration of the sense amplifiers of array 44 will not be initiated. On the other hand, if the time interval for the selected memory cell does not fall in the range from ½AVT to 2AVT, but instead falls into one of the two “recalibrate” time interval ranges from ¼AVT to ½AVT, or from 2AVT to 4AVT, then the sense amplifiers for array 44 are recalibrated.
That is, if a “shorts” or “opens” condition is detected, then the recalibration test result is ignored. A shorted or open-circuited memory cell will not trigger a recalibration of the sense amplifiers of array 44. Similarly, a shorted or opened memory cell will not have been used by the controller circuit 46 to store a data bit. However, if a “shorts” or “opens” condition is not detected, then the results of the testing of the memory cell's resistance is compared to the Recal Hi/Lo limits. So long as the cell's resistance is indicated to be within (i.e., between) the pair of Recal Hi/Lo limits, than sensing of the memory cell proceeds, and no recalibration of the sense amplifier for that memory cell is initiated. On the other hand, if the Recal Hi/Lo limits are exceeded (i.e., meaning that the sensed cell's “time value” is either below ½ATV, or above 2ATV, but not less than ¼ATV or more than 4ATV) then sensing of the memory cell stops, data stored in the memory cell is preserved undisturbed, a sense amplifier recalibration is initiated, and the data stored in the memory cell is sensed later after completion of this sense amplifier recalibration.
Considering now FIG. 6, a preferred implementation of a circuit portion 52 of the calibration controller 50 is illustrated. This circuit portion 52 may be termed an individual sense amplifier portion, and it is switched into connection with a particular memory cell at the same time as the sense amplifier 26 which will be then used to sense that memory cell and as that sense amplifier is then calibrated (i.e., provided that the result of the calibration test explained above is to proceed without a calibration). In fact, the circuit portion 52 and sense amplifier 26 may share circuit elements, as will be clear in view of the explanation below. This circuit portion 52 includes a selected RXPtM cell 14, a capacitance 54 with a charging switch 54′, a comparator amplifier 26′, and a switching junction 56 receiving clock counts 58 from a source 60. The conductivity of junction 56 (i.e., switched either opened or closed) is controlled by a voltage comparator circuit 62. Further, the number of clock pulses which pass through junction 56 while the junction 56 is switched closed is recorded in a counter 64 for data sensing and calibration uses, as will be further explained.
Also included in the illustration of FIG. 6 (which will be recalled to be a schematic circuit diagram) is an indication of the location and effect of a shorted memory cell (i.e., indicated with reference numeral 14′), and of an open memory cell (indicated with a reference numeral 14″). The indications 14′ and 14″ seen on FIG. 6 are provided merely so that the reader will have an appreciation of the location and effect of either a shorted or open memory cell. It will be understood in view of the above, and the following description, that a shorted or open resistive memory cell will be indicated in accord with the above description of the time values obtained for such shorted and open memory cells. That is, it is to be understood that the count value stored in counter 64 is indicative of a particular time interval as is graphically depicted on FIG. 5, so that the time values ¼AVT, ½AVT, 1AVT, 2AVT, and 4AVT are indicated according to a stored digital value in counter 64. Thus, a simple comparison of the digital value of actual clock counts stored in counter 64 to the counts for these time intervals determines whether a time value for the memory cell 14 under the then existing environmental factors for the MRAM chip 40, and with the existing calibration of sense amplifier 26 is acceptable according to the test explained above. If the time value is acceptable, then the count value in counter 64 is stored for use as an indication (i.e., in view of a further test) of the binary value (“1” or “0”) stored in the cell 14 being sensed.
Considering FIG. 6 still, it is seen that the circuit 52 includes a load model 66 for the resistive cross point memory cell. This load model may be considered to be typical (i.e., representative) of the particular resistive cross point memory cell being sensed. Again, this particular resistive cross point memory cell may be shorted, may be open, or may have a normal resistance. However, if the resistive cross memory cell being sensed has a normal resistance, then the sense amplifier 26 may have an acceptable calibration, or may require recalibration before the sensing operation is completed.
The comparator amplifier 26′ is a constant voltage pre-amplifier (indicated generally with numeral 68), which effectively isolates the resistance R (i.e., resistance 14) from the integrator circuit 70. The comparator amplifier 26′ behaves as a current source while maintaining a constant voltage across the resistance 14 of the resistive cross point memory cell being sensed.
An integrator 70 includes the switch 54′, the capacitor 54, and a ground connection (as indicated on the drawing FIG. 6). This integrator allows the load current (i.e., sneak path current plus current through the load resistor R (i.e., resistor 14)) to discharge capacitor 54. The rate of decay of the voltage at the integrator is a direct function of the load current. If the load is shorted (i.e. 14′) then the pre-amp current will be very high and the integrator will discharge very quickly. If the load is open (i.e., 14″), then the integrator 70 will discharge at a rate determined by the sneak path currents and by the circuit design. Then the discharge time will be very large. A normally resistive cross point memory cell (i.e., resistance 14) will cause the discharge time to fall within the range explained above.
Comparator section 72 includes the comparator circuit 62, and a connection to a reference voltage source (indicated on FIG. 6). The comparator 62 controls the gate 56 to open (i.e., switch closure) at the beginning of the integration period, and to close (i.e., switch opening) at the time when the voltage from capacitor 54 equals Vref.
The circuit 52 also includes the counter and storage circuit 74, which includes switching junction 56, a connection to a clock pulse source (indicated at 60) and the counter 64. The result of the stored count value at counter 64 is compared to the reference values (i.e., ¼AVT, ½AVT, 1AVT, 2AVT, and 4AVT) as described above, in order to determine if recalibration of the sense amplifier 26 is or is not necessary.
Finally, it is seen that the circuit 52 includes a representation at 76 of a current source, providing a current (which is a parasitic current) also flowing through the resistance of cell 14. The current source 76 is representative of sneak path currents resulting through the other resistive cells of a cell array, and realized at a particular cell 14 under evaluation.
Again, if the count value of counter 64 does not fall within the range of ½AVT to 2AVT (i.e., as explained above, in accord with this preferred embodiment, and remembering that the invention is not so limited), then the sense operation is suspended, and the sense amplifier 26 is recalibrated before sensing of the cell 14 continues (provided that the cell does not give a “short” or “open” value—recalling the additional indications 14′ and 14″ of FIG. 6).
When the time value for cell 14 falls within the acceptable range from ½AVT to 2AVT (i.e., either before or after recalibration of the sense amplifier 26) then the cell is further sensed by writing either a zero (“0”) or one (“1”) value to the cell, and sensing its resistance value with the same calibration of sense amplifier 26; then the other of a zero (“0”) or one (“1”) value is written in the cell 14, and is sensed again with the same calibration of sense amplifier 26.
Each of these sensing steps gives a count value in counter 64, which is sensed and stored. A comparison between the first sensing count and the second sensing count; and between the first sensing count and the third sensing count, will give an unambiguous indication of which value of value (i.e., zero (“0”) or one (“1”)) was originally stored in the particular memory cell 14. This determined value of zero (“0”) or one (“1”) is then written back into cell 14 to complete the sense process for the particular memory cell 14. Thus, it is seen that the above sensing process includes triple sensing steps each alternating with triple writing steps. Further, in the event that recalibration of the sense amplifier is necessary, this necessity is determined at the first sensing step before the first writing step, and the sense amplifier is then recalibrated. After this recalibration, the triple sense and triple write operation is carried out.
Those ordinarily skilled in the pertinent arts will appreciate that the identities of data values stored in each memory cell 14 of an array 12 is verified by this method contemporaneously with sensing a resistance value indicative of the stored value. That is, a triple sense and triple write process is carried out, with the first step in the process (i.e., the first sense step) being carried out contemporaneously with a test to determine that the particular memory cell and its associated sense amplifier have a proper calibration in view of then existing environmental factors. If not, then the sensing operation is suspended, and the sense amplifiers are all recalibrated. When the calibration factors are within an acceptable range (i.e., determined by a time factor for a cell to be sensed that falls within the range from ½AVT to 2AVT) then the sensing operations continue. Because this method is carried out each time data is to be sensed from a memory cell, the validity of data sensed out of the array 12 is assured.
Accordingly, those ordinarily skilled in the pertinent arts will understand that the invention is subject to modification and change in accord with the spirit and scope of the description and disclosure above. Although reference is made to a particularly preferred embodiment of the invention, such reference does not imply a limitation on the invention, and no such limitation is to be inferred. Further, the invention is not limited to the specific embodiments described and illustrated above. Instead, the invention is to be construed according to the claims that follow, which provide a definition of the invention.
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|US6873543||May 30, 2003||Mar 29, 2005||Hewlett-Packard Development Company, L.P.||Memory device|
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|US6999366||Dec 3, 2003||Feb 14, 2006||Hewlett-Packard Development Company, Lp.||Magnetic memory including a sense result category between logic states|
|US7130235||Sep 3, 2004||Oct 31, 2006||Hewlett-Packard Development Company, L.P.||Method and apparatus for a sense amplifier|
|US7239537||Jan 12, 2005||Jul 3, 2007||International Business Machines Corporation||Method and apparatus for current sense amplifier calibration in MRAM devices|
|US9299746||Oct 12, 2011||Mar 29, 2016||Hewlett-Packard Enterprise Development LP||Select device for cross point memory structures|
|US9378811||Sep 9, 2013||Jun 28, 2016||Samsung Electronics Co., Ltd.||Methods of operating variable resistance memory devices|
|US9431072||Mar 15, 2013||Aug 30, 2016||Silicon Storage Technology, Inc.||On-the-fly trimmable sense amplifier|
|US9667359||May 20, 2015||May 30, 2017||Rambus Inc.||Periodic calibration for communication channels by drift tracking|
|US20040085794 *||Nov 1, 2002||May 6, 2004||Frederick Perner||Memory cell sensing system and method|
|US20040160808 *||Dec 26, 2002||Aug 19, 2004||Unity Semiconductor Corporation||Cross point memory array using distinct voltages|
|US20040179414 *||Mar 10, 2003||Sep 16, 2004||Sharp Laboratories Of America, Inc.||Temperature compensated RRAM circuit|
|US20040240255 *||May 30, 2003||Dec 2, 2004||Smith Kenneth Kay||Memory device|
|US20050013182 *||Jul 18, 2003||Jan 20, 2005||Kenneth Smith||Systems and methods for sensing a memory element|
|US20050122767 *||Dec 3, 2003||Jun 9, 2005||Perner Frederick A.||Memory device|
|US20060050582 *||Sep 3, 2004||Mar 9, 2006||Perner Frederick A||Method and apparatus for a sense amplifier|
|US20060152970 *||Jan 12, 2005||Jul 13, 2006||International Business Machines Corporation||Method and apparatus for current sense amplifier calibration in mram devices|
|US20090103350 *||Oct 18, 2007||Apr 23, 2009||Michael Kund||Method of Testing an Integrated Circuit, Method of Manufacturing an Integrated Circuit, and Integrated Circuit|
|US20170256315 *||Mar 2, 2017||Sep 7, 2017||Infineon Technologies Ag||Resistive memory transition monitoring|
|DE102004019675B4 *||Apr 22, 2004||Jan 21, 2010||Hewlett-Packard Development Co., L.P., Houston||Speicher mit Referenz-eingeleitetem sequentiellen Lesen|
|DE102004030543B4 *||Jun 24, 2004||Feb 5, 2009||Samsung Electronics Co., Ltd., Suwon||Magnetspeicher/Resistiver Speicher mit einem Kalibrierungssystem|
|U.S. Classification||365/209, 365/129, 365/158|
|International Classification||G11C11/16, G11C11/15, G11C29/02, G11C29/50, G11C7/06, G11C29/04|
|Cooperative Classification||G11C29/50, G11C11/15, G11C2207/2254, G11C11/16, G11C29/02, G11C7/06|
|European Classification||G11C11/16, G11C29/02, G11C29/50, G11C11/15, G11C7/06|
|Sep 24, 2001||AS||Assignment|
Owner name: HEWLETT-PACKARD COMPANY, COLORADO
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:PERNER, FREDERICK A;REEL/FRAME:012184/0901
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Owner name: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P., TEXAS
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:HEWLETT-PACKARD COMPANY;REEL/FRAME:013862/0623
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Year of fee payment: 4
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Owner name: SAMSUNG ELECTRONICS CO., LTD., KOREA, REPUBLIC OF
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.;REEL/FRAME:019733/0030
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domain: physics


The solar systems offered by SunPower are ideal due to the very fact that they will produce energy for your home at a rate that's much better than other company's panels. because of the advanced inverter technology, every solar array can operate at peak efficiency in the least times. With other systems, the whole installation had to work at the extent of rock bottom producing panel, which dramatically hamper on the quantity of power that would be produced. this is often alto the technology that's helping to form solar a legitimate power generation option for more New Jersey homes than ever before.
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EVISA - Who we are
The establishment of EVISA is funded by the EU through the Fifth Framework Programme (G7RT- CT- 2002- 05112).
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Directory of scientists
US FDA, Forensic Chemistry Center, 6751 Steger Drive, Cincinnati, OH 45238
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In general, my research interests focus around elemental speciation in FDA regulated products (foods, drugs, cosmetics, etc.) Specific speciation interests include:
HPLC-ICP-MS for arsenic, chromium, iodine, selenium, and phosphorus speciation in foods and drugs.
HPLC-ESI-MS for confirmation/identification of various elemental species.
Specific arsenic related interests include speciation of arsenic in rice, rice products, and fruit juices
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domain: chemistry


gravity-separation-methods-in-barytes-beneficiation 4 Common Barite Beneficiation Methods Miningpedia. Generally the choice of barite beneficiation method is affected by factors such as ore type raw ore properties mine scale and use. At present the commonly used barite beneficiation methods mainly include hand sorting gravity separation flotation magnetic separation and combined process.Get Quote Online
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Kelly Ann Osmolinski-Smith, American medical/surgical nurse. Registered Nurse, Pennsylvania; certified pediatric nurse, trauma nurse, lactation counselor; certified Basic Cardiac Life Support, Pouch Attachment Ladder System, others. Member York Adams Metropolitan Medical Response Sy., since 2002; Member American Cancer Society (board directors, chairperson).
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domain: health


Natural Gas Distribution
Natural gas is actually methane, a hydrocarbon gas, composed of one carbon atom and four hydrogen atoms (CH4), and is a product of natural decay and decomposition of organic material.
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The industry includes organizations focused on production, distribution, lobbying, regulation, and sustainability.
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domain: relationship


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How many times has it been said that if politicians had to run the government like Americans had to run their household, we would not be in debt as a country? And when it comes down to it, we as taxpayers should literally be looking at our politicians who were put into their positions of power by us as our disobedient and very irresponsible young teenagers whom we have just entrusted with our expensive automobile. What do you think’s going to happen?
If we thought for one moment when this country was first formulated as a free nation that we would have to babysit our politicians and hold them by the hand in order to guide them to make the right decisions, there is no way that we’d have stood for them disobeying our wishes or making disparaging remarks about us to the press!
Take Hillary Clinton for example. If she was a politician running for office a hundred years ago, and had made those famous remarks about us being a basket of deplorables and irredeemables (in essence calling us “basket cases” or insane who our political beliefs) she would have been run out of town by both parties! The Americans that founded this country and stood their ground against the greatest fighting force on the planet at that time…and won…would have been outraged that a woman who was living on the taxpayer dole – for 35 friggan’ years – had called us crazy!
Politicians have gotten so comfy-cozy with their cushy jobs that they have long forgotten WHY they are serving the American people. They have forgotten what it means to be a CIVIL SERVANT. They get into their position, see everyone around them spending money like it’s monopoly money and, eventually, fall right into the mode and mentality of believing that THEY are in charge…THEY are the bosses! There isn’t a company on Earth where the employees get paid MORE than their employers…except ONE: and that is the Government. It is a proven and undeniable fact that our CIVIL SERVANTS get paid, on the average, five to seven times what we get paid! Does that sound like “humble service” to you?
There is also the matter of their staff. Each one of these politicians has a bevy of staffers, assistants and coffee-fetchers who, on the average, also get paid a lot more than we do. Why do you think government work is so coveted? Once you’re in, the money spigot is endless and you don’t ever have to worry about anything, financially speaking. The average government workers…all 2-3 million of them in just the federal government alone…earn an average of $72K a year! Are you earning half that much?
And now there’s a report that shatters our perception of how much is being spent on the government attempts to recover money that’s owed to them.

domain: economics


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However, pay levels at the charity are far lower, with its high earner, director Declan O'Mahony, being paid £177,407 in 2017/18. He left the charity on 29 March 2018, two days before the end of its financial year. One area where the top 100 charities appear to be falling down is in naming those who earn the highest amounts Charity Navigator Releases In-Depth Study on Charity CEO Pay. GLEN ROCK, N.J., October 3, 2013 -The typical charity's chief executive officer received a 2.5% raise and received $125,942 in compensation, according to Charity Navigator, the nation's leading charity evaluator and donor advocate.. The study examined CEO compensation at 3,929 mid to large sized charities in America to help.
An Irish Sun study reveals charity CEO salaries range from €159,800 to less than €70,000 Credit: Getty Images - Getty 25 The average top charity salary in 2019 was €113,100, compared to 2018. The chief executive started in April 2001. *23 The previous salary represents the midpoint in a £10,000 salary range, but the charity said the chief executive received a pay rise of 2.5%. (The. Forbes ranks America's largest charity and non profit organizations. Covid-19 has energized giving to United Way Worldwide, but its impact on other big charities is still unclear .
The Philanthropy Outlook 2020 & 2021 study, which was published in February shortly before COVID-19 was officially declared a pandemic, projected inflation-adjusted growth rates for giving by. Giving money Between January and June 2020, the public donated a total of £5.4 billion to charity - an increase of £800 million compared to the same period in 2019. What people give t
Give Thoughtfully. CharityWatch, founded in 1992 as the American Institute of Philanthropy (AIP), is America's most independent, assertive charity watchdog.CharityWatch does not merely repeat what a charity reports using simplistic or automated formulas. We dive deep to let you know how efficiently a charity will use your donation to fund the programs you want to support This is around £80,000 more than he was earning at the time of the 2017 survey. The top ten earners are as follows: Steve Gray, Nuffield Health. Pay range: £840,000-£850,000. Jeremy Farrar, Wellcome Trust. Pay: £456,000. Simon Cooke, Marie Stopes International. Pay: £435,000. Al Russell, London Clinic Trustees Grants to individuals for travel, study, or other similar purposes (including loans made for charitable purposes, and program-related investments) are taxable expenditures, unless the following conditions are met:. The grant is awarded on an objective and nondiscriminatory basis under a procedure approved in advance by the Service, and; It is shown to the satisfaction of the Service that one.
Charity Navigator 2016 CEO Compensation Study. October 11, 2016. Share. Download study. At Charity Navigator we receive numerous inquiries from donors, reporters and nonprofit board members asking what is an appropriate level of compensation for a charity CEO?. IRS rules state that nonprofit CEOs should receive 'reasonable compensation.' BBB Wise Giving Alliance produces evaluative reports on charities based on 20 BBB Standards for Charity Accountability that address four charity areas: governance, results reporting, finances, and truthful and transparent communications.. There is no charge to charities for the accountability assessment and resulting reports are freely accessible on Give.org Prior low was 79% in 2009. 29% have donated or volunteered for COVID-19 relief efforts. WASHINGTON, D.C. -- At a time when more Americans are in need of assistance but fewer are in a financial position to be able to provide it, Gallup finds a new low in the percentage of Americans reporting they donated money to charity By Jay Kennedy, Director of Policy and Research, DSC Published on 24 January, 2020 This report follows upon a Charity Commission investigation into the charity Marie Stopes International last year, which paid its Chief Executive a remuneration package totalling over £400,000
. Some of these programs may also help pay for drugs Part B covers, such as oral anti-cancer drugs. Note: This table is not comprehensive Charity care disparities among nonprofit hospitals. The researchers found that, overall, nonprofit hospitals in 2017 generated $47.9 billion in net income and provided $9.7 billion in charity care to uninsured patients, as well as $4.5 billion in charity care to insured patients who couldn't afford to pay their medical bills The CEOs in the 2020 study a saw slightly smaller pay increase at the median when compared to 2019, as well as 2018, when there were increases of 7.2% and 8.5%, respectively. The highest-paid CEO in this year's study was Lisa Su, CEO at Advanced Micro Devices, who becomes the first woman to top the list since the study's inception
22,850. Source: CharityComms and Charity People Salary Survey 2020 Get the data Created with Datawrapper. f. in. Other key figures included: The average salary at a larger charity (100+ employees) is £41,470, which drops to £35,524 at charities with less than 100 staff, and £31,985 at charities with 10 staff or less Self Storage DEMAND STUDY 2020 Edition Produced and Distributed by the Self Storage Association in conjunction with NAXION Research & Consultin The organization's goal is to improve the health and financial situations of 10 million senior citizens by 2020. 16. Best children's charity to donate to: Prevent Child Abuse America. This 501(c)(3) charity proudly designates 94% of its of its cash budget to programs that directly relate to its mission of stopping child abuse and neglect in. In the UK charities pay a monthly subscription fee of £15+VAT if the charity's total fundraising is less than £15,000. If over £15,000 the monthly subscription is £39+VAT. Processing fees are 1.9% + 20p and there's a 5% charge on Gift Aid, too. Funds are delivered to the charity on a weekly or monthly basis ..
The CEOs in the 2020 study a saw slightly smaller pay increase at the median when compared to 2019, as well as 2018, when there were increases of 7.2% and 8.5%, respectively. The highest-paid CEO in this year's study was Lisa Su, CEO at Advanced Micro Devices, who becomes the first woman to top the list since the study's inception You can obtain these publications free of charge by calling 800-829-3676. You may deduct charitable contributions of money or property made to qualified organizations if you itemize your deductions. Generally, you may deduct up to 50 percent of your adjusted gross income, but 20 percent and 30 percent limitations apply in some cases
February 2020 1 The 2019 Benchmarking Study from Charles Schwab was fielded from January to March, 2019. The study contains self-reported data from 1,310 RIA firms. Hiring data represents firms with $250 million or more in AUM Independent charity providing products and services to other charities in the UK and internationally. Events, research, news and information about the organisation is available on the site The organizations on Charity Navigator's 2021 list of the 10 Best Charities were selected from the more than 8,000 nonprofits that are evaluated each year by the charity watchdog agency. The 2021 rankings account for a charity's efficiency, financial performance, transparency, and accountability
. There are about 166,000 charities in the UK, employing 827,000 paid workers. About 1 in 50 people in employment in the UK work in charities If you're a nonprofit organisation looking to start fundraising online amidst the coronavirus pandemic, PayPal can help. Even before the pandemic, 39% had found themselves unable to donate to charity because they weren't carrying cash - preferring newer, digital ways to donate 1.The importance of embracing online donations is clear, and with a network of 300+ million PayPal users in 200.
This Code is a practical tool to help charities and their trustees develop high standards of governance. Read more about this Code, using this Code to review governance and extra advice from our steering group partners. The Code refresh. The Code steering group refreshed the Code at the end of 2020 The increase is 2.75% on all pay points applicable from 01 April 2020. As the NJC pay points are widely used in the voluntary and community sector in Northern Ireland, NICVA produces the attached document which group the NJC payscales into pay bands/grades for guidance only. NJC payscales go from point 1 to point 43 Afterpay Launches Fundraising Push For 2 Charities. Afterpay, which works in the buy now, pay later (BNPL) space, will help deal with the fallout of the pandemic by asking customers to donate to. Great Ormond Street Hospital Children's Charity. A company limited by guarantee (company number 09338724) and a registered charity (charity number 1160024). Registered office: 40 Bernard Street, London WC1N 1LE This study aims to explore the integration of knowledge at an international development charity from the perspective of its workforce. Design/methodology/approach Rich primary data were collected through an in-depth case study of a large international development charity actively embracing the management of knowledge using semi-structured.
'Not Plan A': Charities are stepping up to pay for elections By NICHOLAS RICCARDI September 16, 2020 GMT FILE - In this April 12, 2019, file photo, morning clouds cover Capitol Hill in Washington, as Congress leaves for a two week recess CHICAGO, Feb. 19, 2020 — One in five Americans reported that they or someone in their household have contributed to a crowdfunding campaign to pay for medical bills or treatments, according to a new AmeriSpeak® Spotlight on Health survey from NORC at the University of Chicago Trump Ordered to Pay Eight Separate Charities $250,000 Each. Remaining $1.8 Million in Trump Foundation Bank Account Disbursed Among Charities. NEW YORK - New York Attorney General Letitia James today released the following statement after Donald J. Trump was forced to pay more than $2 million in court-ordered damages to eight different charities for illegally misusing charitable funds at.
Economists have found that donors give more to charity when the stock market fares well.But stocks usually decline during recessions. 2. Foundations and individuals stepped up. Soon after the COVID-19 pandemic began, many foundations pledged to increase their grantmaking.Based on our findings, it looks like they kept their word: Foundation giving rose 15.6% to a record $88.55 billion in 2020. Employee Benefit News (EBN) reports that it costs employers 33% of a worker's annual salary to hire a replacement if that worker leaves. In dollar figures, the replacement cost is $15,000 per person for an employee earning a median salary of $45,000 a year, according to the Work Institute's Retention Report 3. Take advantage of carryovers or bunching. Give beyond limits. Donors who itemize deductions may give more than the 60% AGI limit for cash and 30% AGI limit for non-cash assets in 2020, and then.
Revenue & Customs Brief 25/10 explains HMRC's policy of pay-per-click charity advertising on sponsored links, including the treatment of 'natural hits' and direct placements on third party. . Marking the report's 10th anniversary, the 2021 Millennial and Gen Z Survey reveals two generations demanding social change and accountability. Download the Deloitte Global 2021 Millennial and Gen Z Survey The Alternative Guide to Postgraduate Funding was created by two PhD students who secured over £50,000 in charity grants towards their studies between them. As well as offering practical tips for identifying suitable organisations and making successful applications, the Alternative Guide runs a database of more than 1,000 charities
Accessed June 22, 2020. Internal Revenue Service. Charitable Contribution Deductions. Accessed June 22, 2020. Planned Giving Design Center. Charitable Gifts of Life Insurance. Accessed June 22. Congress should consider, as part of its next relief bill, an Emergency Charity Stimulus to inject more than $200 billion into the economy, protectney out to charities doing urgent work. In fact, America's 728,000 DAFs—which hold an estimated $120 billion—aren't legally required to pay out their funds at all, ever University funding for disabled students. Student loans can help with course fees and living costs while you study. You can apply for funding to cover extra costs if you are disabled. This includes Disabled Students' Allowances (DSAs) and bursaries from universities or charitable trusts. Unlike student loans, you do not have to pay these back An embattled veterans charity had the chance to make a fresh start. It's still struggling. 2020. A Charity for Disabled Veterans Raised Nearly $300 Million. DVNF agreed to pay the other.
2020 RIA Benchmarking Study from Charles Schwab. 8. Past performance is not an indicator of future results. 2020 RIA Benchmarking Study from Charles Schwab, fielded January to e arly April 2020. Study contains self -reported data from 1,010 firms for the main study and 761 firms for the compensation portion How donating to charities can affect your 2020 taxes. Over half of Americans, 55%, gave to charities last year, with about one in four donating up to $500, according to a recent survey I have now applied for Charity Care to pay this hospital bill. I am waiting for a determination from _____Hospital on my Charity Care application. WAC 246-453-020 requires you to suspend collection activity until the hospital makes a decision on my application
Who are the 2020 consumers? Four distinct consumer segments emerged from the anal - ysis of our survey, each one representing different areas of focus (see Figure 1): 1. Value-driven consumers (41 percent of all consumers) want good value, convenience, and products/services to simplify life and are willing to pay for those benefits McLoughlin's channel puts on charity livestreams monthly for various causes close to his heart, including a January 2020 stream that raised more than $212,000 for Australian wildfire relief and. Important Updates Regarding the 2020 Version of the Civics Test. Beginning on April 19, 2021, USCIS is administering only the 2008 civics test to N-400 applicants at their initial interview appointment, regardless of their filing date. USCIS will no longer offer the 2020 civics test at the initial interview, but will continue to provide study materials for the 2020 test for those applicants. BIRMINGHAM, Ala. (WBRC) - Experts with Charity Navigator say you should research charities and the authenticity before you donate.. Charity Navigator is an online tool that helps evaluate non-profits. It is the largest in the United States. Director of Marketing Stacy Steele said on Giving Tuesday, the website saw 49% more people donating on their website compared to last year
Six in 10 suffer musculoskeletal pain from poor homeworking practices. Almost a quarter (23%) said they experienced musculoskeletal pain most or all of the time, and 46% said they had been taking painkillers more often than they would like. Lower back pain was the most common complaint identified by the charity's survey, with 50% of. I recently discovered the list below of the charities with the highest paid staff in the country and it makes for very distressing reading. As a matter of policy, the Ten-Percent Foundation will not be donating to any charity in future that pays a CEO or equivalent more than £75,000, which we believe is a reasonable wage to be paying a decent manager or director involved in a non-profitable. A Kaiser Family Foundation survey in 2018 found that 67 percent of Americans worry about paying for unexpected medical bills. By way of comparison, only 43 percent expressed similar concern about. The study highlights how much relief has come from friends, family and charity. Once the pandemic hit, it took time for any government response to trickle down, Haynes-Maslow said The highest paid FTSE 100 CEO received a total pay package of £58.73 million. This is 1,935 times the median salary of a full-time UK worker. Six firms paid their CEOs more than £10 million in total. For the financial year ending 2019, FTSE 100 CEOs took home a median pay package worth £3.61m, which is 119 times greater than the median.
This year (as for 2020), Americans who donate to charity will receive a charitable tax deduction whether they itemize or take the standard deduction. Plus, if you itemize, you can deduct more for. Report 2020 2 - 1 Key points and figures 3 - 2 Forewords 5 - 3 Executive summary 10 - 4 Recommendations: A five-point plan of action 13 - 5 Economic abuse: My money, my life - five years on 15 - 6 Research and methodology 19 - 7 Findings: Prevalence 22 - 8 Findings: Experience of economic abuse 30 - 9 Findings Breast Cancer Now is a company limited by guarantee registered in England (9347608) and a charity registered in England and Wales (1160558), Scotland (SC045584) and Isle of Man (1200). Registered Office: Fifth Floor, Ibex House, 42-47 Minories, London EC3N 1DY Payscales 2018 - 2020. The payscales for 2018 - 2020 have been updated to reflect the changes to the NJC pay spine for 2019/20. The NJC payscales, which are local government payscales resulting from negotiations between the employer and trade union sides of the National Joint Council, have been reformed for 2019/20, year two of the pay agreement
100 SW Market Street VOICE (971) 673-1880 . Portland, OR 97201-5702 TTY (800) 735-290 Credit Card Debt Study. Alina Comoreanu, Senior Researcher Jun 8, 2021. Alina Comoreanu, Senior Researcher Jun 8, 2021 . U.S. consumers continued to pay off their credit card debt during the first quarter of 2021, building on a record-setting performance in 2020. While 2020 was a year to forget in most respects, Americans excelled in terms of. Canada's best charities 2020: Top 100. Acceptable pay range Bruce Trail Conservancy 97.5% 100% 94% High funding need Environment 11.3% 11.1% N/A Acceptable pay range. charity: water is a registered charity in the UK. To make a tax-efficient donation in GBP, visit charitywateruk.org. For other international donations, we accept bank issued money orders in USD. Money orders should be made payable to charity: water and can be mailed to the address below
The charity and voluntary sector often referred to as the 'third sector', 'not-for-profit sector', 'community sector' or 'civic sector', aims to create social rather than material wealth. According to the UK Civil Society Almanac 2020 the voluntary sector contributed £18.2billion to the UK economy in 2017/18. The 166,592 voluntary. This bundle was live from Jul 21, 2020 to Aug 4, 2020 with 20,087 bundles sold, leading to $183,784.01 raised. Learn more about how we work with charities here. Return to the homepage, use the search bar above, or click on any of the links below on related bundles or sales Concerning the issue of atheism and charity, charitable giving by atheists and agnostics in America is significantly less than by theists, according to a study by the Barna Group : . The typical no-faith American donated just $200 in 2006, which is more than seven times less than the amount contributed by the prototypical active-faith adult. In April 2020, the reference period for calculating holiday pay in the UK will change. The move comes as part of the UK government's ongoing effort to improve transparency between employers and employees, and will particularly affect employees who work variable hours: those in seasonal roles or on zero hours contracts, for example On June 15, 2020, Independent Sector released the following results of a survey on the impact of COVID-19 on large and mid-sized nonprofit organizations. The survey illustrates that the pandemic and the resulting economic shutdown has had significant effects on the services, operations, and the people working in the nonprofit sector. In general, the surve
Buy Now, Pay Later Is A Booming Industry BNPL services are seeing 200%-plus increases during COVID-19. With cash-strapped customers turning to payment deferment methods in order to make purchases during the pandemic, the BNPL sector has achieved record growth throughout 2020 Nationwide Retirement Solutions wins State of Indiana 457, 401 (a) deferred compensation retirement plans. The State of Indiana has a new retirement plan provider for its more than 59,000 participants.Nationwide Retirement Solutions, based in Columbus, Ohio, has won the Indiana Public Employees' Deferred.
The housing charity is warning that unless the government acts to protect the renters thrown into financial difficulty by COVID-19, judges will be powerless to stop them from losing their homes once the ban lifts. Case study: Jeanny, 48, lives in Bournemouth with her three children. fieldwork 4th June to 11th June 2020 6. Did your charity operate in the 2020 reporting period. A charity is classed as 'operating' if it undertakes any activities or programs. These activities can be financial - for example, spending money on projects or overseeing programs - or non-financial or strategic - for example, planning, employing staff or completing administrative work Movember is an all day, every day, year-round mission that needs year-round support. Help us reach more men and save more lives. Give Monthly. 2 OF 6. Give Monthly. 2 OF 6. Movember Conversations. Visit Movember Conversations for ways to connect with a mate who might be struggling. Take a look Charity Intelligence has released its list of Top Impact Charities for 2020. They are ranked by how much impact there is for each dollar donated. and that charities do not pay for ratings or.
Phishing impersonations and business email compromise attacks designed to steal victims' bitcoin surged by 192% between October 2020 and May 2021, closely following the rising demand and increasing price of bitcoin over the last eight months [FIGURE 1], according to new analysis by Barracuda Networks, the trusted partner and leading provider for cloud-enabled security solutions, in their. The very first Hertz-Hendrick 2020 Chevy Camaro ZL1 production model was recently auctioned at the Barrett-Jackson LIVE Las Vegas Auction, raising $250,000 for charity. The auction proceeds will. Similarly, a 2003 study (reported in the Jewish Journal) found that 24.5% of all mega-donors (people who donate more than $10 million a year to charity) are Jewish. Nor is Jewish generosity limited to Jewish causes: while a few of the Jews in BW's Top 50 list Jewish causes among their primary charitable targets, most don't


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Designs and develops educational content that engages and inspires for preK–12, adult learning, higher education, or publishing.
6 Months Project
Six Red Marbles wanted us to provide meaningful e-learning content on different subjects like Maths, Physics, Chemistry, Biology, Language, Social Science, etc. Our responsibility is to provide descriptive, step-by-step solutions and explanations for the procured questions.
The challenge is to decode subject matter, using the most appropriate time tested and innovative methods, and 100% plagiarism-free solutions in keeping with the given deadline.

domain: mathematics


The Kacie Jacket from Kollontai is a show-stopping piece made from French jacquard. It has a large shawl collar and short dropped sleeves, with a single button closure. It has two large front pockets. Wear it over your favourite dresses, jumpsuits, or leggings, for a stand-out look. It come in Brick in sizes XS/S or M/L.
Fabric: 60% Cotton, 35% Polyester, 5 Elastane.
Care Instructions: hand wash and dry flat. Iron on the reverse side.
Made in Montreal.


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Kernza® Whole Grain
Kernza® Whole Grain
What is Kernza®?
Kernza® is a perennial wheatgrass. It has a truly delicious, sweet, nutty flavor, and can be used in baking, cooking, and brewing.
Why Cook with Kernza®?
Cook with Kernza® because it's delicious! What's more, Kernza® is a healthy whole grain that's high in protein, high in antioxidants, and has eight times the amount of insoluble fiber as wheat. Buying and eating Kernza® grain and flour is a tangible way to support scalable solutions to climate change and agricultural water pollution, while enjoying a new, flavorful food. Do good, eat well.
What is Perennial Agriculture?
Perennial agriculture is the solution to many challenges we face from grain production today. Perennials are plants that can be left in the field to return for several years without the annual tilling that damages topsoil and leads to erosion and nutrient losses. Perennials develop a deep root system that helps sequester carbon, filter water, and keep continuous living cover on the land. Their ecosystem services offer contrast to the greenhouse gas-intensive practices of modern annual agriculture. They produce nutritious food crops while protecting natural resources, a win-win for farmers, farming communities, food companies, and home cooks. Learn more at Kernza.org.
Kernza® contains gluten and is non-GMO. Processed in a facility that contains nuts.
Only available in the United States.
Kernza's kernels softened and expanded after soaking and simmering according to the package directions, producing a wonderful al dente slightly chewy texture. The kernels in my package were very well cleaned. (I'm growing some garden Kernza, so I know how difficult it is to remove the hulls.) The few kernels (six in one cup) that were still encased in their hulls floated to the surface of the soaking water, where they were easy to skim out before cooking. (I squeezed the kernels out of their hulls, and returned the kernels to my pan. Kernza is especially satisfying sweetened with honey and mixed in with oatmeal or other cereals, but the mildly nutty flavor balances savory recipes, also.
Delicious and interesting new find!
Interesting flavor. Still refining my cooking technique, but am really enjoying it in grain bowls for lunch, and like supporting sustainable progressive agriculture.
This was my second purchase. Have prepared and served this to several different eaters. All liked it. I cook the grain in the same water used for soaking to save all the flavors and nutrients and have shared with others including the developers.
Love the whole grain Kernza in oatmeal mix

domain: agronomy


After the successful Comox Valley Paddle Festival last weekend, BC Hydro is shifting operations to consider the summer chinook migration up the Puntledge River.
River flows along the stretch of river from the diversion dam to the generating station will double, but other areas of the river will remain about the same as BC Hydro reduces flows out of the generating station.
The public is advised to be cautious within the Barber’s Hole, Nymph Falls, Stotan Falls section of the river every Tuesday and Wednesday from this week through to July 10.
The timed river flow increase over the next five weeks will allow chinook to migrate past river obstacles and access upstream fish habitat. The base flow within the five-kilometre stretch of river below the diversion dam will double to about 12 cubic metres per second.
The river flow increase may seem relatively benign but river areas like the potholes or small waterfalls near Stotan Falls, for example, can change river-flow hydraulics and be a hazard. This is especially the case for people who go into the river the day before the migration flow is in place and then not notice the difference the following day.
BC Hydro reminds you to be cautious.
— BC Hydro


SMX Convention Center, Pasay City
March 23, 2023
Underscoring the significance of safeguarding the Philippines’ water management and supply, President Ferdinand R. Marcos Jr. pushed for the establishment of the Department of Water Resources as the need to attain water security intensifies amidst the adverse effects of climate change.
He made these remarks during his attendance to the 6th Edition of the Water Philippines Conference and Exposition, where he highlighted the need to discuss ways to lessen water crisis in the country. Recently, he signed an Executive Order (EO) creating the Office of Water Management to ensure sufficient water supply for the country.
“There are many agencies that are involved in water supply and water management. It has just evolved that way. But what we are going to try to do is make more cohesive policies so there is planning at a national level. And in that way, we can maximize the management of what water we have,” the President said.
The Chief Executive emphasized the utilization of collective actions in using the available technologies and stratagems in light of the existing water crisis across the nation, noting the “debilitating effects in the economy if water crisis continues to be felt” most especially in the fields of agriculture and food security.
“I am very optimistic that the solutions that we need to formulate are out there. The technologies are out there. What has continued to change in the light of climate change is the management, the stratagems on how we manage our water,” he expressed.
President Marcos Jr. conveyed his gratitude to the conference organizers for holding such an assembly as he considered this a “necessary and urgent step towards achieving our collective aim of attaining water security, and providing safe and accessible drinking water for the Filipino people.”
Organized by Informa Markets and the Philippine Water Works Association, Inc. (PWWAI), the three-day affair is the country’s leading event when it comes to international water supply, sanitation, industrial wastewater treatment and purification. It serves as a venue for over 10,000 trade participants, as well as industry players and leaders, with more than 300 exhibiting companies presenting overviews of their latest products, technologies and innovations.
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Contact me by email or cell
I love photographing weddiings and events in the San Francisco bay area as well as destination weddings around the world. My mission is bring out the beauty and emotion of the day so these memories are with you forever. I have a very artistic eye and see magic where others may not. I hone in on these moments and capture authentic and organic photographic art to tell your story. My favorite thing about photographing weddings is that this is just the beginning of your new chapter. I am so deeply honored to forge these deep friendships where I continue to photograph pregnancies, growing families, portraits and all that life has to offer. I'm really grateful that for almost twenty years I love what I do.

domain: photo


WHITE HAVEN, PA --
The U.S. Army Corps Engineers’ Philadelphia District announced the schedule for the final water release of the recreation season for the Francis E. Walter Dam in White Haven, PA.
The Army Corps’ Flow Management Plan allows for a final large water release as part of drawing the reservoir down to its winter level. The schedule and water release amounts for the final weekend will be as follows:
- Thursday, October 7, 2021, 1:00 a.m. – 1000 cubic feet per second
- Friday, October 8, 2021, 1:00 a.m. shift to 4000 cubic feet per second
- Saturday, Oct. 9, 2021, 1:00 a.m. – shift to 1700 cubic feet per second
- Saturday, Oct. 9, 2021, 1:00 p.m. -- shift to 850 cubic feet per second
- Sunday, October 10, 2021, 1:00 p.m. – shift to matching inflow
- *Release values assume a 500 cubic feet per second inflow
The Francis E. Walter Dam was constructed by the U.S. Army Corps of Engineers in 1961 and has prevented more than $245 million in flood damages.
Release no. 21-031


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Problem Entertainment pushes back the release date of “Seclusion” a dramatic black and white short film, due to needed post-production time.
Charlottetown, PE – Problem Entertainment has announced the release date of August 31, 2018 on Seclusion, to be pushed back to the following month; with a new release date of September 21, 2018.
“Seclusion” is a dramatic short film written by Shawn Martin and John Houston, starring John Houston and directed by Shawn Martin. The film is produced by Shawn Martin and John Houston under the Problem Entertainment banner.
The film follows Ben, a young man whom after a tragedy several years prior, lives his life in seclusion. The film follows one of those days.
The film was originally set to release on August 31, 2018 but due to a much more complicated post-production than anticipated, will now release the following month.
The film’s needed extra post-production time is due to the nature of the film being black and white and the unexpected needing of visual effects that were not initially noticed while filming.
The film will release on September 21st, 2018 on YouTube and will be able to purchase the same day on various digital media outlets. Editing will be done by Shawn Martin at Joseph James Pictures with music by Josh Woodward, while the soundtrack is to be released by SR71 Records, a label of the Unbreakable Music Group.
The film will be released in black and white and was the first film to be shot in multiple locations.
It is the first production shot using the Canon EOS 1200D (Rebel T5) as well as the first production to not be produced nor distributed under the Joseph James Pictures brand as both production and distribution will be handled by Problem Entertainment.
Production stills were handled by Solar Red Photography, a brand under the Solar Red Publishing Group of brands of Problem Entertainment.
The film will be made available on DVD exclusively through Amazon.com at a later date.
For more information on Seclusion and where to buy the film, visit its official listing on the Problem Entertainment website here.

domain: movie


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Download Full Report: here
Your Financial Models Are Wrong!
Investment Managers Use Incorrect Return Assumptions in Their Models
Measuring and modeling financial returns are important for investors to understand their risks and expectations. Understanding how frequently worst-case events can happen has become increasingly important as we're in the 9th year of a bull cycle and valuations are above their long term averages. Money managers use financial models to measure the risk and return profiles of their investment returns, the problem is that they're doing it wrong.
Most of the widely used financial time series models assume financial returns or the logarithm of financial returns are normally distributed. However, many empirical studies have shown that the distributions of financial returns are non-normal and heavy-tailed, indicating that extreme values, especially negative shocks, are more likely to occur than the investment managers model for (Müller et al., 1998; Cont et al., 2001; Ibragimov et al., 2013). Due to the increasing market volatility over the past decades and the challenges for traditional financial models to capture the heavy tail risks, it is crucial to examine the true distribution of financial returns and the risks inherited in using stylized financial models.
1. Assuming the market behaves normally is wrong
Widely used financial models, including the famous Nobel winner models, Black Scholes Merton and Generalized Autoregressive Conditional Heteroskedasticity (GARCH), assume that returns or the noise of returns are normally distributed. The main reason these models assume return normality is simplicity. The symmetric bell-shaped normal distribution with most of the densities concentrated around the mean is easy to model. The problem - financial returns are actually not normally distributed! The significant divergence between the true return distribution and normal distribution could result in inaccurate estimates and forecasts of future returns or risks.
2. The market has significantly more negative returns than accounted for
In this section, several techniques are used to examine the behavior of financial returns. We take daily S&P 500 returns from 4/19/2005 – 4/18/2018, 3273 observations.We plot the S&P 500 returns as well a normal distribution with the same mean and standard deviation as the S&P 500 returns.
Figure 1: Density plots of daily S&P500 returns and normal distribution: the black normal density plot is symmetric and the left and right limit of the normal density on the x-axis are set to match the minimum and maximum values of the S&P500 return observations.
Figure 1 shows that daily S&P500 return density significantly diverges that of a normal distribution. First, we implemented Jarque-Bera normality test and Quantile-to-Quantile Plot to further confirm that the S&P 500 returns are statistically significantly non-normal. Jarque-Bera normality test is a common tool for normality testing. The null hypothesis is a joint hypothesis of the skewness being zero and the excess kurtosis being zero, which implies a normal distribution. From Table 2 we could see that the JB Test Statistic is very high and the p-Value is very small, indicating that the S&P 500 returns are significantly non-normal.
Table 1: Jarque-Bera Test for S&P 500 Returns
Figure 2 shows the Quantile-to-Quantile Plot for the S&P 500 returns. We could see that the empirical distribution quantiles diverge from normal distribution quantiles as well as the 95% confidence intervals for the normal quantiles. Therefore, we could conclude that the S&P 500 returns are significantly different from a normal distribution with the same mean and standard deviation.
Figure 2: Quantile-to-Quantile Plot for S&P 500 Returns. The red solid line is the quantiles of the normal distribution. The red dashed line is the 95% confidence interval for the quantiles of the normal distribution. The black dots are the quantiles for the S&P 500 returns empirical distribution.
From Figure 1, we could also see that the left tail of the S&P500 returns are slightly heavier than the normal benchmark. To further confirm the heavy-tailedness of returns, we compare the number of observations (exceedances) that are beyond 2 standard deviations from the mean for both the S&P500 returns and the empirical distribution.
Note: the number of exceedances for S&P500 returns are taken directly from the empirical return density. The number of exceedances for the normal distribution is estimated through the normal density function, so the decimals are expected here. The lower tail cut-off point is -2.36% and the upper tail cut-off point is 2.43%.
Table 2 shows that the number of exceedances of the lower tail is higher than that of the normal distribution and the number of exceedances of the upper tail is slightly lower than that of the normal distribution. This result confirms our initial guess that financial returns have heavier lower tails, which infers that negative shocks are more likely to happen than the widely used normal assumption.
In addition, to illustrate the heavy-tailedness of returns over year. We also plotted the number of lower tail exceedances over year from 2005-2018 on Figure 3. It is shown that the highest number of exceedances occurs on 2008 and the number of exceedance drops sharply after 2011. Moreover, 3 exceedances have already been observed in the first 4 months on 2018 while there are only 11 exceedances in total between 6 years from 2012 to 2017. The 3 largest negative shocks on 2018 occur on 2/5/2018, 2/8/2018, and 3/22/2018. Our observations indicate that financial returns on 2018 could be more volatile than previous years and thereby investors should be more cautious about the heavy-tailedness in the markets.
Figure 3: The number of exceedances on the lower tail from 2015-2018: the number of exceedances is obtained from S&P 500 returns that are lower than -2.36%, which is 2 standard deviation from the return mean from 2015-2018.
3. Normality in financial models
In the previous section, we concluded that S&P 500 returns are significantly non-normally distributed. In this section, we examine the widely applied financial models that assume normality and why these models may generate inaccurate results during periods of high volatility.
a. Value at Risk (VaR)
VaR is the most commonly used method to quantify the future risks of an asset or a portfolio. An example of VaR is represented as “portfolio i has 95% probability of losing no more than 1 million dollars in the next 10 days". "Variance and Covariance" method, or "Analytical" method is used very often to estimate VaR. This method typically assumes the asset return or the logarithm of return if normally distributed. The VaR estimation starts with estimating the mean and variance of the portfolio using time decaying methods, such as Exponentially Weighted Average (EWMA), and then derive the VaR estimator by taking the quantile value on the normal distribution density with previously estimated mean and variance. It is easy to observe the VaR could be highly biased when the asset returns are not normally distributed and have heavy tails because the VaR will simply underestimate the unexpected risks that assets will lose more than the value drawn from a normal density. More advanced methods, such as Expected Shortfall (ES), has been proposed to better quantify the tail risks, but the VaR still relies on the assumption of normally distributed returns. Obviously, VaR is very likely to fail to give descriptions of unexpected risks, especially the "black swan" events in the past few decades.
b. GARCH volatility models
The GARCH volatility models have been widely applied in return volatility forecasting due to its power to explain the inherited relationship between lagged returns and volatilities.
The simplest GARCH (1,1) model could be represented as:


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BS-ISO-13073-1 › Ships and marine technology. Risk assessment on anti-fouling systems on ships. Marine environmental risk assessment method of biocidally active substances used for anti-fouling systems on ships
The following bibliographic material is provided to assist you with your purchasing decision:
Environmental cleanliness, Ships, Foul-sewage drainage, Risk assessment, Marine transport, Vessels
To find similar documents by classification:
This document comes with our free Notification Service, good for the life of the document.
This document is available in either Paper or PDF format.
BS ISO 13073-1:2012
Nov. 30, 2012

domain: library


Rob Allen Closed Muzzle
25mm OD. Rob Allen glass reinforced nylon muzzle is made for use with one band. The integrated band elevating design increases accuracy by reducing muzzle jump, and maximize the power by redirecting the force 100% forward.
The entire muzzle is constructed from 30% glass reinforced nylon with an internal spigot and outer skirt for additional strength. The skirt also reduces stress concentration when fitted to carbon barrels.


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After a successful test in five markets including Denver, Chipotle Mexican Grill said it will add chorizo to the menus at all of its U.S. restaurants starting Tuesday.
Chipotle tested the spicy pork and white-meat chicken sausage at a couple of restaurants over the past few years, but never pulled the trigger on a rare, chainwide edit of its closely curated menu until now.
Chipotle’s chorizo is seasoned with paprika, toasted cumin and chipotle peppers, then seared to the perfect char on a hot grill, the company said. It will be available in burritos, tacos, burrito bowls and salads.
“The reaction to chorizo in the cities that have had it has been overwhelmingly positive, so we’re making it available in all of our restaurants across the country,” said Chipotle founder and co-CEO Steve Ells said in a news release. “Our chorizo is made with Responsibly Raised chicken and pork, and provides a delicious new option that fits perfectly with the rest of our menu.”
The nationwide launch of chorizo comes just in time for National Taco Day, which is celebrated each year on Oct. 4.

domain: news


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A MALNOURISHED wombat’s journey to recovery at Perth Zoo has sparked a consultation period to draft more robust wildlife rehabilitation licences.
Young wombat Miniri received expert care at Perth Zoo after wildlife officers found her malnourished and critically ill with hair falling out and nails overgrown in Kalgoorlie in September.
ABC News reported the Kalgoorlie woman who kept the wombat as a pet and fed it breakfast cereal was fined $6000 for animal cruelty in March.
Department of Biodiversity, Conservation and Attractions seeks input on the licence and fee structure for wildlife rehabilitators following Miniri’s case.
Environment minister Stephen Dawson said the consultation would make sure people providing care to animals were properly trained, properly networked and could talk to the experts.“If you find a distressed, wild animal on the road, please make sure you bring them to the experts,” he said.
“Over the next three months, we’ll be consulting with the community, with wildlife rehabilitators about the new licences we’re planning to bring in WA.
“I encourage all wildlife rehabilitators to participate in the consultation which will have a positive impact on the care provided to our native fauna.”
Feedback on the licence opens today at https://pws.dbca.wa.gov.au/faunalicences.

domain: biology