A flexible data rate matching method in a 3GPP2 system is disclosed that supports flexible data rate repetition on a physical layer of synchronous cdma2000 in an interleaving process. The process includes repeating bits of a channel encoded bitstream with one of a plurality of repetition factors, for matching a length of a repeated bitstream to an interleaving depth, or alternatively, fixing an index of an offset bit, where bit repetition of the channel encoded bitstream is started therefrom, for making the repetition pattern of the channel encoded bitstream to be a desired bit repetition pattern, fixing a repetition factor according to an initial parameter defined by the index of a fixed offset bit, repeating a bit of relevant index, and updating the initial parameter according to the fixed repetition factor, and repeating a process of fixing the repetition factor of a next bit according to the updated initial parameter, repeating the next bit, and re-updating the updated initial parameter, for matching a length of the repeated bitstream to the interleaving depth.

1. Field of the Invention
The present invention relates to a communication system, and more particularly, to a data rate matching method in a 3GPP2 system.
2. Background of the Related Art
In general, the 3GPP2 (the 3rd Generation Partnership Project 2) system has two transmission modes in addition to a regular data rate mode. These modes are a flexible data rate mode and a variable data rate mode.
The regular data rate mode is a transmission mode operative on a fixed chain called a Radio Configuration (RC). The RC represents a kind of transmission chain in which lengths of information data, channel interleaver, and an output bitstreams from a channel encoder according to a code rate of channel codes, are made the same to form a standard. In this instance, there is a certain standard rule among the length of the channel interleaver, the coding rate of the channel encoder, and the length of a channel Walsh code.
That is, once a chip rate to be used is fixed, a number of chips required for one modulated symbol is fixed according to the length of the channel interleaver, which may be defined as a spreading factor, according to which the length of the Walsh code, that can subject different channels to code multiplexing, is fixed. The number of available Walsh codes is proportional to the length of the Walsh code. Therefore, the number of channels that a multiplexing channel can accommodate varies with the Walsh code.
For example, suppose lengths of input information bit sequence have the same lengths after being subjected to a channel coding process. In this instance, the capability of error correction code for correcting possible errors in the channel becomes stronger as the coding rate of the channel encoder becomes lower. That is, the lower the coding rate of the channel encoder, the higher the error correction capability. This permits a lower transmission power to be used.
However, using a low channel coding rate lengthens the output bitstream of the channel encoder, which, in turn, elongates the length of the channel interleaver. As a result, a modulation symbol rate is increased, thus reducing a number of chips required for one modulation symbol at a fixed chip rate, and reducing the number of Walsh codes.
Alternatively, if a high channel coding rate is applied to input bit sequences of the channel encoder of identical lengths, lengths of output bit sequences of the channel encoder become short, even though the error correction capability is low. This decreases the modulation symbol rate, thus permitting the use of a short channel interleaver, to increase a number of available Walsh codes.
From the above description, it is understood that there is a certain trade off between the coding rate of the channel encoder and the Walsh code spacing.
The RC is a standardized transmission chain useful when securing the Walsh code spacing is desirable, or when a lower transmission power is required, taking such a trade off relation into account. In the 3GPP2 system, there are currently several standard RCs for 1× system of 1.2288 Mcps chip rates, and several standard RCs for 3× system of 3.686 Mcps chip rates. It should be noted that, since the spreading factor has a value in a form raised to the second power, both the input data rate and the length of the interleaver defined in each of the RCs also have forms raised by a factor of two.
Before a channel is formed between a mobile station and a base station, the mobile station and the base station determine the RC to be used and the spreading factor on the RC, i.e., the length of the channel interleaver, through negotiation for processing a communication matched to the chain. Modes in which the transmission chain differs from the transmission chain defined in the RC are (i) the flexible data rate mode and (ii) the variable data rate mode.
In the flexible data rate, any data transmission rate other than the standard data transmission rate supported on the RC can be supported. For example, in cdma2000, transmission channels with various symbol rates are adjusted into transmission channels with optimal symbol rates by applying symbol repetition or puncturing thereto. In the adjustment of the symbol rate, a flexible data rate method is generally used, which is a method for supporting any transmission rate other than a standard transmission rate supported in RCs of the cdma2000.
The flexible data rate was introduced to support an Adaptive Multi-Rate (AMR) CODEC, one of speech CODEC in the 3GPP2 on a physical layer. Data bits not consistent to the standard RC transmission rates in present cdma2000 support in a 20 ms frame length may be provided in a case of the AMR. In this instance, as one example, the length of the data bits inconsistent with the standard transmission rate may be matched with a length of data at a transmission rate supported in the RC by using a zero padding on a physical layer. Alternatively, the length of the data bits inconsistent with the standard transmission rate may be matched with a length of data at a transmission rate supported in the RC by means of symbol repetition and puncturing between a channel encoder and a block interleaver for optimizing the data rate (flexible data matching).
On the other hand, the variable data rate mode has been provided under the following purpose. In the 3GPP2 system, the base station makes transmission scheduling to a forward supplemental channel, when the base station assigns a fixed data transmission rate to the mobile station for a time period by means of a message. However, a channel situation between the base station and the mobile station during the particular time period may be changed, and a system load on the base station may be changed. For example, as the mobile station goes farther from the base station, the channel quality becomes poorer, until the base station lacks enough transmission power to transmit data to a particular mobile station at the current data transmission rate.
To solve this problem, the base station may stop transmission of data to supplementary channels for the time period. However, such a solution causes delays in data transmission, as well as needless waste of available transmission power and Walsh codes.
As an alternative, the base station may re-schedule the data transmission rate after a time period is passed. However, this alternative also causes the problem of time delay and waste of the Walsh codes.
The occurrence of this situation is not limited to the forward link. Thus, the channel situation between the mobile station and the base station may also vary with movements of the mobile station in the reverse link. This can cause a lack of transmission power required to sustain an appropriate quality. Consequently, the variable data rate mode is used to solve such a situation.
In the variable data rate mode, the transmission rate is varied with frames depending on situation. That is, if the channel environment is determined to be poor, the base station drops the transmission rate of the supplementary channel. When the channel environment is determined to be restored, the base station restores the transmission rate of the supplementary channel. Provided that such a variable data rate mode is applied, the base station can use available power without frequent re-scheduling.
A related art flexible data rate matching method will be explained with reference to FIG. 1.
A bitstream with a length 'I' is provided to a channel encoder, and encoded into a bitstream with a length L (=nI) (step 10). In this instance, a number 'M' of repetition is fixed according to the following equation, where 'N' denotes an interleaving depth of a block interleaver used in the present RC. The channel-encoded bitstream is symbol repeated in 'M' times (step 11).
                              M          =                      ⌈                          N              L                        ⌉                          ,                            (        1        )
Here, ┌x┐ denotes the smallest integer equal to, or greater than 'x'. The length of the output bitstream after the bitstream passes through a symbol repeater is L*M. If the length of the output bitstream of the symbol repeater has a value greater than a depth 'N' of the block interleaver, the length of the output bitstream is punctured for matching with a desired depth of the interleaver (step 12). Accordingly, an amount 'P' of puncturing required for one frame can be expressed as the following equation (2).P=LM−N  (2)
For carrying out such a puncturing, at first, a puncturing distance 'D' is defined as follows.
                    D        =                  ⌊                      LM            P                    ⌋                                    (        3        )
Here, └x┘ denotes the greatest integer not greater than 'x'. That is, 'P' bits of L*M bits of a bitstream passed through the symbol repeater are punctured at 'D' intervals at indices 'D', '2D', '3D',—when the (L*M) bits of the bitstream are indexed from '1' to (L*M). Consequently, the size (length) of the punctured bitstream is the same with the size (depth) 'N' of the interleaver (step 13). Thus, the matching of the flexible data rate is done over two steps of symbol repetition and puncturing in the related art.
Thus, as described before, the length of the channel interleaver used in each RC is fixed according to the spreading factor. Since the spreading factor has a value in a form raised by a power of 2, a ratio of the length of the interleaver fixed according to one spreading factor to the length of the interleaver fixed according to another spreading factor one step lower than the one spreading factor is exactly 1:2.
If the greater spreading factor is represented with 'A' and the smaller spreading factor is represented with 'B', a 1:1 mapping can be established between the spreading factor and the input information bitstream of the channel encoder in each RC. If lengths of the input information bit sequence of the channel encoder are represented with IA for the spreading factor 'A' and IB for the spreading factor 'B' respectively, a relation of IB=2*IA is established. If the lengths of the channel interleavers to be used are represented with NA and NB respectively, a relation of NB=2*NA is established.
If it is assumed that a coding rate of the channel encoder (using turbo codes or convolution codes) in the present RC is 1/n as illustrated in FIG. 1, taking the flexible or variable data rate mode into account, in which an 'I' (a length of an information bitstream having CRC bits, tail bits, and reserved bits added thereto in steps 10 and 11) is a length of the input bitstream of the channel encoder, that meets a non-regular data length of "IA<I<IB", the input 'I' will provides an output "n*I", when "NA<n*I<NB" is also met (step 12).
Consequently, a certain operation for matching the length of the output bitstream of the channel encoder "n*I" to the length of the interleaver is required. A method currently used in 3GPP employs is that the length L (=n*I) of the output bitstream of the channel encoder is matched to the interleaver of N=NB to require a bit repetition of "NB−n*I" (step 13), according to the following uniform repetition process. That is, a (k)th output symbol of a repetitive block can be predicted starting from a code symbol of
      (          ⌊                        k                                                              L                N            ⌋        )      thinput bitstream for an index k increased from '0' up to 'N−1'.
Next, a method for supporting the variable data rate mode will be described. In the variable data rate mode, a highest data rate supportable in the initial negotiation process, a data rate one step lower than the highest data rate, and data rate two steps lower than the highest data rate are defined as a transmission data rate set. Accordingly, in the variable data rate mode for the present supplementary channel, the data transmission rate can be adjusted between the supportable highest transmission rate and the two step lower transmission rate.
In the forward channel, the mobile station can only determine a rate variation by blind rate detection. Therefore, if a range of a data transmission rate variation is taken too large, an operative complexity of the mobile station is increased. The lengths of the channel interleaver and the Walsh codes, used in the highest transmission rate, should not be changed. That is, the interleaver and the Walsh codes used in the highest transmission rate presently should not be changed. If the data transmission rate is dropped to half of the highest transmission rate, two times of symbol repetition is required for matching the length of the interleaver to be used on the channel and the length of the output bitstream of the channel encoder.
Similarly, if the data transmission rate is dropped to a quarter of the highest transmission rate, four times of symbol repetition is required for matching the length of the interleaver to be used on the channel and the length of the output bitstream of the channel encoder. The foregoing example is applicable to a case of forward supplementary channel of a non-flexible data rate.
The variable data rate mode for the flexible data rate can be supported in the supplementary channel. However, in this case, the definitions of the flexible data rate and the variable data rate mode themselves become vague. That is, even if the highest data rate in the variable data rate mode is a regular rate in the present RC and the one step lower data rate is also a data rate fixed in the present RC, the one step lower data rate can already be taken as a flexible data rate that uses no transmission chain fixed in the present RC. This is because the length of interleaver in the variable data rate mode, i.e., the spreading factor, is in a state fixed as the spreading factor at the highest transmission rate.
As one example, consider a RC4 of the present forward channel, when the turbo codes or convolution codes of ½ rate is used. It is assumed that the highest transmission rate useable in the variable data rate mode is 76.8 kbps, when the length of the interleaver used in the forward RC4 is fixed at 3072. A variable data rate method in this mode will be discussed.
It is assumed that an appropriate value from a set of usable data transmission rates {19.2 kbps, 38.4 kbps, and 76.8 kbps} is used. Though data transmission rates of 19.2 kbps, and 38.4 kbps are the transmission rates defined in the RC4, there is no chain that connects the transmission rates to the 3072, the present interleaver length, in the RC. Therefore, those transmission rates may be taken as the variable data rates.
If the chain has an interleaver length fixed at 'N' even in the variable data rate mode and the present data transmission rate not defined in the present RC, the length of output bitstream of the channel encoder and the fixed interleaver length can be matched by means of the aforementioned uniform repetitive algorithm.
Once a transmission chain for supporting the flexible data rate or the variable data rate is included to an existing regular chain, a basic function block diagram as illustrated in FIG. 1 can be formed. A RC 5 on a forward link will be described as an example with reference to FIG. 1.
A reserved bit of '0' or '1' is added to channel bits (S10), and CRC bits are added to channel input bits having a length for detection of an error (S11). After the CRC bits are added to the channel input bits, tail bits or the reserved bits are added to the bit sequence (S12). When a convolution code is used, 8 tail bits are added, and when a turbo code is used, 6 tail bits and 2 reserved bits are added. The CRC and reserved bits, and the tail bits are added to form one information bit sequence, which is then channel coded into turbo codes or convolution codes (S13), subjected to symbol repetition (S14) and symbol puncturing (S15) to match with a desired interleaver length, and block interleaved at the block interleaver (S16).
As shown in FIG. 1, a symbol repetition is performed on an existing chain after channel coding in turbo codes or convolution codes, and then the symbol puncturing is performed. Therefore, both the symbol repetition and the symbol puncturing are operative on an existing regular data rate chain. However, as explained before, since an actual rate adaptation is made through a uniform repetition process in a symbol repetition block in the flexible and variable data rate operations, the symbol puncturing block is inoperative.
The method of symbol repetition in the related art has various problems. For example, it requires buffering for the length of output bitstream of the symbol repeater. Moreover, because, in the puncturing, the original bitstream is subjected to an 'M' times of symbol repetition to form an input bitstream greater than an interleaver block depth 'N' and the puncturing is made on the input bitstream, a method of symbol repetition changed from the related art is required for avoiding excessive repetition of an unnecessary bitstream to form an appropriate input bitstream for the puncturing block depth.
Additionally, Table 1 shows problems of a variable data rate operation mode in the forward link RC5, and in the backward link RC4. In the table 1, it is assumed that a virtual set of the variable data rate has {115.2 kbps, 80 kbps, 57.6 kbps}. Then, a size of a desired channel interleaver for a maximum allocated data rate is 6144. A chain for 115.2 kbps, the maximum allocated data rate, may be assumed to be an existing regular data rate chain, and, according to this, as can be known from FIG. 1, 4 symbols out of 12 code symbols are punctured for rate adaptation.
TABLE 1Length of InformationLength of a coderdesireddata rateoutput sequenceRate matchinginterleaver115.2 kbps2304 * 4 = 92154 bit puncturing among 126144bits (regular chainpuncturing)  80 kbps1600 * 4 = 6400Inoperative6144 57.6 kbps1152 * 4 = 46081536 symbol repetition6144
The symbol puncturing pattern for puncturing 4 symbols out of 12 symbols is defined in 3GPP2 for turbo codes and convolution codes as a sort of fixed pattern. Next, a chain for 57.6 kbps may be assumed to be a sort of flexible chain, when a 1536 bit uniform symbol repetitive algorithm is required for matching a length of a 4608 bit output sequence of the channel coder to a size of a 6144 bit interleaver. Then, operation of the puncturing block in FIG. 1 is stopped. However, the problem in the table 1 is a length of 6400 bits of the output sequence form the channel coder in 80 kbps is already greater than a desired length 6144 of the channel interleaver. Therefore, it is impossible to complete an existing regular chain by using an existing symbol repetition block.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.


An apparatus and method that insures an even distribution of liquid in an aquatron charging device across the entire length of the device. This enables uniform charging across the width of the photoreceptor. The present invention fills and pressurizes a porous tube with a liquid. The liquid evenly exudes from the pores along the entire length of the porous tube. A hydrophilic liquid retentive foam which contacts the photoreceptor surface is wrapped snugly around the tube. The conductivity and overall rate of dispensation of liquid is controlled by the pressure differential across the porous tube.

Liquid (e.g. aquatron) charging is an ozone-free contact charging technique that is based on the electrification of a water contact to the photoreceptor surface. It is advantaged over other contact charging techniques in that it provides excellent charging uniformity over a wide range of process speeds, e.g. to 50 ips, using a DC-only voltage. Furthermore, it is nearly 100% efficient, operating at near theoretical voltage and current levels. However, in order to obtain excellent charging uniformity over a long period of time, it is necessary to insure a uniform delivery of liquid, typically water to the aquatron contact to the photoreceptor in a practical and efficient manner.
The following disclosures may be relevant to various aspects of the present invention and may be briefly summarized as follows:
U.S. Pat. No. 5,602,626 to Facci et al. discloses an apparatus for applying an electrical charge to a charge retentive surface by transporting ions through an ionically conductive liquid and transferring the ions to the member to be charged across the liquid/charge retentive surface interface. The ionically conductive liquid is contacted with the charge retentive surface for depositing ions onto the charge retentive surface via a wetted donor blade supported within a conductive housing, wherein the housing is coupled to an electrical power supply for applying an electrical potential to the ionically conductive liquid. In one specific embodiment, the charging apparatus includes a support blade for urging the donor blade into contact with the charge retentive surface and a wiping blade for wiping any liquid from the surface of the charge retentive surface as may have been transferred to the surface at the donor blade/charge retentive surface interface.
U.S. Pat. No. 5,510,879 to Facci et al. discloses a process for charging layered imaging members by the transfer of ions thereto from an ionically conductive medium.
U.S. Pat. No. 5,457,523 to Facci et al. discloses a device for applying an electrical charge to a charge retentive surface by transporting ions in a fluid media and transferring the ions to the member to be charged across the fluid media/charge retentive surface interface. The fluid media is positioned in contact with a charge retentive surface for depositing ions onto the charge retentive surface, In one specific embodiment, the fluid media is a ferrofluid material wherein a magnet is utilized to control the position of the fluid media, which, in turn, can be utilized to selectively control the activation of the charging process.

Control of fluid carrier resistance and water concentration in an aquatron charging device


Method and apparatus for use in a computer having peripheral data storage, to monitor data transfers to detect defective or marginally defective storage areas. The method and apparatus are based on a memory-resident program component and a transient program component which cooperate. The resident component is in the computer's interrupt chain, to be invoked during both the initiation and conclusion of storage operations. When a data access is called, a timer (e.g., the system timer) provides interrupts at a suitably high rate, and informs a second component of the operation. At the conclusion of the operation, error indications are logged into a log file. The second component accumulates interrupts during the operation, and monitors one or more memory addresses. For each monitored address, when its contents first change, the second component stores the current interrupt accumulation. Following the operation, the first component applies algorithms to the accumulations and decides thereby whether to log an error indicator. A third component places the first component in the storage call chain in one of two positions, including a preferred position providing raw status rather than processed status with some information removed. An analysis program retrieves the log entries, clears the log for future entries, adds the entries to a history of the storage, and applies algorithms to the history to determine whether storage areas are defective. It also takes remedial action such as marking a defective storage area bad and relocating the data to a usable area.

1. Field of the Invention
This invention relates in general to systems which operate in real time to monitor data retrieval operations of peripheral storage media and log events indicating the occurrence of any difficulty in retrieving data, and which subsequently, not in real time, take remedial action based on analysis of the logged data. The invention relates more specifically to systems which perform the aforementioned functions in microcomputer or personal computer environments.
2. Prior Art
Currently, there are computer programs for testing computer peripheral storage media, particularly rotating magnetic storage, to determine whether there are areas that are bad or marginal with respect to storing data with integrity. A large majority of these programs accomplish the task by writing and reading areas of a storage medium repeatedly to determine the reliability of the areas. If an area does not meet some selected threshold of reliability, then the area is marked bad according to the procedures of the operating system, and data is relocated if possible. Common to such conventional programs is the fact that, except in context switching environments, they must be run as separate, stand alone programs with no other programs (other than the operating system) running concurrently. In other words, normal computer operations must be suspended while these programs are run to test the storage medium. This is wasteful of time and resources, and the requirement that they be run alone dictates that they do not test a storage medium in the actual program environments in which it is normally used. Moreover, many conventional test programs require that most or all memory-resident programs and data storage caching be removed or disabled before testing. So, in fact, the tests are done in a simulated program environment. Also, the physical environment is very often different since the tests are typically run at times when the computer is not performing its usual functions. For example, in a business office, the tests are typically run during non business hours to avoid interfering with business operations. Unfortunately, line power to the computer may have different characteristics at those times, and ambient temperature and humidity may be different, all of which may have an effect on the performance of the storage medium under test. So, there is great advantage in being able to monitor the data storage performance of the medium in its normal operating environments.
Another disadvantage in conventional test programs which is overcome by the system of this invention arises as a result of conventional storage medium controller retry strategies in personal computers. For example, in a personal computer, if in a first attempt a conventional storage medium controller is unable to retrieve a block of data without a data error, it will retry the data retrieval operation one or more times. These retries may be very significant indications of defective or marginal areas of the medium, but the retries are completely hidden because they are not reported to the operating system. Thus, conventional programs do not have ready access to one of the best sources of information on media quality.
However, it has been found that read retries can very often be detected by a program by making certain time measurements of data retrieval operations. Although most personal computers provide a system timer for making time measurements, it is very difficult to measure accurately the time duration of data retrieval. Some of the conventional programs described above, which operate on personal computers and which suspend normal operations while being executed, measure the total elapsed time for a disk read operation by counting or accumulating conventional system timer interrupts. However, the rate of such interrupts in a typical personal computer is too low to make accurate measurements, since a typical single access time might be half the time between interrupts, or less. In an attempt to make more accurate measurements, some conventional test programs read the contents of the system timer counter at the start and end of an operation. These programs may first disable the system timer, look at the contents of the timer counter, start the data retrieval operation, and at the end of the data retrieval operation will again look at the contents of the timer counter. This method may provide more accurate timing information than simply counting conventional system timer interrupts, but only the total elapsed time of the data retrieval operation can be measured in this manner.
A significant problem with both of these conventional methods lies in the fact that a data retrieval operation may exhibit some rotational latency time and may also include seek latency time. In other words, a measured elapsed time could include the time it took for the storage controller to position a read head over the area of the medium from which the data was read. It then becomes necessary to separate out the rotational and/or seek latency time from the actual data read time. Distinguishing between the actual read time and the latency time can be accomplished to a limited extent in a conventional test program by conducting seekless read operations, however, this requires that normal functions of the computer be suspended while the test program runs special disk read operations. Therefore, and also since some problems which may be aggravated by seek operations are not brought out, these reads are not representative of actual operating conditions. So, there is great advantage in being able to measure the time duration of data retrieval operations which occur while the computer is performing its usual functions and being able to accurately distinguish seek and rotational latency times from actual read times. Heretofore, personal computer operating systems and applications software have not included program-based systems which had the capability of measuring the read time portion of a data retrieval operation.
Some conventional storage medium controllers have the capability of correcting a limited number of data errors. Typically they employ an error correction code (ECC) which is recorded along with the data. When the data is retrieved, this code is used to correct data errors within its capability. The fact that the controller had to employ the error correction code to correct data during a data retrieval operation may, for disk drives, be a very strong indication that the area or areas from which the data was read are defective or marginally defective; for other disk drives, the ECC is invoked very frequently, as a routine matter, and the fact that it was employed on a particular read operation is of no consequence. Controllers employing ECC typically report to the operating system that an error correction has taken place, but most operating systems used on personal computers do not pass that information on to user programs. So conventional test programs, being user programs, have no way of knowing whether or not error correction activity has taken place with respect to a read operation. Since information regarding ECC activity can be very valuable in evaluating the storage capability of a medium, it would be very advantageous, in such systems, for a test program to have access to information indicating whether or not an error correction operation had taken place.

System for locating and anticipating data storage media failures


A DC-DC converter circuit includes an inductor having an inductor current, an inductor current emulation circuit for producing an emulated inductor current, and a control circuit coupled with the emulation circuit for receiving the emulated inductor current and determining a peak inductor current for the DC-DC converter.

DC—DC power converters are commonly used for supplying power to electronic devices and systems, such as power supply devices, computers, printers and imaging systems. Such DC—DC converters are available in a number of configurations for outputting a desired voltage from a source voltage, including a buck or step down converter (FIG. 1), a boost converter (FIG. 2), and a flyback converter (FIG. 3). FIG. 1 is a circuit diagram of a DC—DC buck converter 100 having an inductor 102, a capacitor 104, switches 106a and 106b, along with a rising cycle path 108a and falling cycle path 108b, for producing an output voltage Vout that is less than a source voltage Vin. FIG. 2 is a circuit diagram of a DC—DC boost converter 200 having an inductor 202, a capacitor 204, switches 206a and 206b, along with a rising cycle path 208a and falling cycle path 208b. FIG. 3 is a circuit diagram of a DC—DC flyback converter 300 having an inductor 302, a capacitor 304, switches 306a and 306b, along with a rising cycle path 308a and falling cycle path 308b.
In order to effect control of DC—DC converter and voltage regulator circuits, accurate measurement of inductor current is necessary. A common approach for sensing an output inductor current in a buck converter (FIG. 1) utilizes a sensing resistor connected in series with the output inductor. The output inductor current is reconstructed as a differential voltage across the sensing resistor. The output voltage is then regulated with current mode control, where the sensed signal is used for output voltage feedback. An example of such a DC—DC converter with a sensing resistor is shown in U.S. Pat. No. 5,731,731. Other examples of direct sensing of inductor current for DC—DC converter control include those shown in U.S. Pat. Nos. 5,982,160 and 6,377,034. FIG. 4 is a circuit diagram of a conventional DC—DC buck converter 400 with a control circuit 402, a sensing circuit 404 and a sensing resistor 406. The sensing resistor value, however, must be sufficiently large in magnitude in order to keep the sensed signal above noise. A serious efficiency drawback results from power being unnecessarily dissipated by the sensing resistor.
Indirect sensing or deriving inductor current for DC—DC converter control is also available. Examples of indirect sensing of inductor current include those shown in U.S. Pat. No. 6,381,159 and U.S. Patent Application Publication No. US 2002/0074975. Although indirect sensing does not require a sensing resistor, a drawback is the requirement that internal nodes of the converter be tapped for internal voltages, which results in additional circuitry and signal pins.
There is thus a general need in the art for a system and method for inductor current control that can overcome the aforementioned shortcomings in the art. A particular need exists for a system and method for inductor current control in DC—DC converters that is efficient, and also minimizes power dissipation problems. A further need exists for a system and method for inductor current control in DC—DC converters with efficient and optimized circuit design.

Programmable inductor current control for DC-DC converters


A classification system has a classification server that receives data for an email and determines if the email message is suspicious, legitimate but failing authentication, forwarded or fully authenticated and legitimate when the domains are owned, or not owned, by the domain owner. Email messages are categorized and presented in a report that enables the email sender to identify and fix a network, malicious traffic, and legitimate messages that have failed authentication beyond control. It also highlights where everything is going well.

1. Field of the Invention
The invention relates to email fraud detection, prevention, and mitigation.
2. Background of the Related Art
Email is a widely used communication channel for companies ("domain owners") of any size or type, and there is very limited technology in place to verify the authenticity of an email message, its sender, and its origin. It is easy to counterfeit an email whereby an illegitimate originator of an email can purport that an email message comes from a domain owner's domain but it in fact comes from a different source. The result is rampant phishing, financial scams, malware, etc. being delivered via email fraudulently appearing to originate from a trusted source. Phishing emails may contain links to websites that are infected with malware. Phishing is typically carried out by e-mail spoofing or instant messaging, which often direct a user to a fake website whose look and feel are almost identical to the legitimate one.
There are email data exchange mechanisms in place that report information about email flows to "domain owners" that are available universally. These exchange mechanism provide varying levels of insight to fraudulent email streams.
(1) One of the most widely used exchange mechanisms is the email "Feedback Loop". Most email mailbox providers (e.g., Yahoo!, AOL, Gmail) offer a way for email mailbox owners to flag a received email as unwanted. This is usually called the "Spam" button. When an email recipient determines that a received email is unwanted they simply click the "Spam" or equivalent button. The email mailbox provider then creates a message called a "complaint" containing a small report and a copy of the unwanted message. Normally the complaint is sent to the "domain owner" of the unwanted email as defined by the "return-path" header within the email message, RFC 3834. Return Path Inc. hosts "Feedback Loops" on behalf of various mailbox providers. The data generated by the "Feedback Loops" is referred to as "Complaint" data. The specifications for this data are defined in RFC 6449 for Complaint Feedback Loop Operational Recommendations, and RFC 6650 for Creation and Use of Email Feedback Reports: An Applicability Statement for the Abuse Reporting Format (ARF).
(2) A second type of email data exchange mechanism is DMARC (Domain-based Message Authentication, Reporting and Conformance). DMARC is an open specification draft for the purpose of reducing email fraud through the enforcement of established email authentication mechanisms of DKIM (DomainKeys Identified Mail) and SPF (Sender Policy Framework). DMARC combines the authentication checks provided by DKIM and SPF with an identifier alignment check to calculate a DMARC pass or fail status for an email. The alignment identifier check is the comparison of the FROM DOMAIN (RFC5322), MAIL FROM DOMAIN and DKIM DOMAIN. Mailbox providers or Email Receivers are encouraged to use the DMARC pass or fail to determine delivery to an email recipient. Domain Owners enable DMARC checks for their mail streams by publishing a TXT record in DNS per the DMARC specification. The DMARC TXT record contains configuration parameters related to DMARC's reporting and policy enforcement capabilities. Policy will be discussed below in the Policy section.
DMARC provides two different types of data. The primary data type is an aggregated report of all email received from a specific "From domain" for a given time period, usually one 24 hour period. The aggregate report provides a summary of all email traffic broken down by SENDING IP ADDRESS, a count of emails received and the status of the respective DMARC checks, DKIM, SPF and identifier alignment. This report is referred to as a DMARC Aggregate data. The next data type is called a Forensic Report. A Forensic Report is generated by an email Receiver when an email fails the DMARC test. A Forensic report contains a brief machine-readable report and a full or redacted copy of the offending email message. The format of the Forensic report is currently defined by RFC 6591. This report type is referred to as a DMARC Forensic data. The relevant RFCs are RFC 6376-DomainKeys Identified Mail (DKIM) Signatures, RFC 4408-Sender Policy Framework (SPF) for Authorizing Use of Domains in E-Mail, Version 1, dmarc_draft-base-00-03-Domain-based Message Authentication, Reporting and Conformance (DMARC), RFC 6591-Authentication Failure Reporting Using the Abuse Reporting Format, RFC 5322-Internet Message Format.
(3) A third type of email data exchange mechanism that exists is not available to the general public. Domain Owners are usually only given access to the data, often indirectly, via business agreements with E-mail/service providers, security companies, or related businesses. This non-public email data exchange information can be used to diagnose fraudulent email and includes spam trap feed, private aggregate data, private message level data and subscriber data.
A Spam trap network is a collection of user email accounts that are designed to catch spam or fraudulent email by way of not publishing or providing the destination mailbox's email address. Any messages received at these unpublished mailboxes are typically fraudulent in nature. A Spam Trap feed includes data generated by these spam trap networks, and can include full email message samples for all mail sent into the Spam Trap network.
Mailbox providers can provide data feeds that specifically contain data for specific mail senders. There are two types of these feeds. The first is private aggregate data authentication data. This type is similar to the DMARC aggregate feed mentioned above, except that the format is non-standard and customized. The second type of feed is a private authentication failure message feed called private message level data throughout, which is also similar to the DMARC forensic type. Many of these feeds pre-date DMARC Forensic and consequently use a nonstandard authentication failure report format. Some newer private authentication failure message feeds incorporate the Authentication Failure format used by DMARC Forensic reports.
(4) The fourth type of data feed which is provided by email account plug-ins such as Other Inbox, operate email account owners with a mechanism to organize their inbox, for example by automatically categorizing the email messages they receive. As part of this mechanism, anonymous user mailbox data can be generated that includes redacted fraudulent email message samples that can be used to perform forensic analysis of the source of the spam and fraud. This includes attributes of the message such as SENDING IP ADDRESS, MAIL FROM, FROM Address, Subject line, and body content including URIS. Additionally, this feed includes meta data for each message describing email user interactions specifically, if the email reached the users inbox which is referred to as inbox placement. This data is referred to as Subscriber Data, such as discussed in U.S. Patent Publication No. 2013-0282477 and U.S. Patent Publication No. 2014-0280624, titled System And Method For Providing Actionable Recommendations To Improve Electronic Mail Inbox Placement And Engagement being filed herewith, the entire contents of which are hereby incorporated by reference.
Of the reporting mechanisms listed above, DMARC and private data feeds enable a domain owner to publish a policy to receivers of email that asserts that a domain owner properly authenticates all of its domain's email messages and if a receiver receives an email message that fails authentication verification, the policy can instruct the receiver to quarantine or reject the email message. Thus prior to publishing a policy, the domain owner needs to verify that it does in fact properly authenticate all email messages sent from a given domain. See "Proactively Block Phishing and Spoofing Attempts" Return-Path-Domain-Protect-FS-9.12—2.pdf, and dmarc_draft-base-00-03-Domain-based Message Authentication, Reporting and Conformance (DMARC).
However, all of the data provided by the listed data exchange formats are very difficult to analyze, normalize and interpret, and not every type of data exists across all mechanisms.

Real-time classification of email message traffic


Fluorescent dyes, fluorescence energy transfer dye couples, multi-color dye sets, can be employed in art-recognized assays and certain novel methods, such as in proximity assays.

The non-radioactive detection of biological analytes utilizing fluorescent labels is an important technology in modern analytical biotechnology. By eliminating the need for radioactive labels, safety is enhanced and the environmental impact of reagent disposal is greatly reduced. Examples of methods utilizing such fluorescent detection methods include DNA sequencing, oligonucleotide probe methods, polymerase-chain-reaction product detection, immunoassays, and the like.
One example of analytical equipment employing fluorescent dyes is flow cytometry, a method for detecting, classifying, and characterizing various analytes including biological cells and other particles such as viruses or molecules that exhibit specific characteristics. In a flow cytometer, a flowing liquid stream containing analytes in a liquid medium is directed to an irradiation region. A radiation source, usually a laser, irradiates the analytes, and optical and electronic detection equipment and processors are used to measure spectral properties of the sample, including light absorption, scattering, fluorescence, or phosphorescence to detect the presence of the analytes.
The use of simple fluorescent markers typically entails a purification step to separate bound and unbound fluorescent markers, in order to obtain precise measurements without background interference from the (unbound or bound) group not being measured. Such purification steps add undesired time and expense to what should be a rapid automated process.
In many important applications the independent detection of multiple spatially overlapping analytes in a mixture is required, e.g., single-tube multiplex DNA probe assays, immuno assays, multicolor DNA sequencing methods, and the like. In the case of multi-loci DNA probe assays, by employing spectrally distinguishable fluorescent labels, the number of reaction tubes can be reduced thereby simplifying experimental protocols and facilitating the manufacturing of application-specific kits. In the case of automated DNA sequencing, multicolor fluorescent labeling allows for the analysis of multiple bases in a single lane thereby increasing throughput over single-color methods and reducing uncertainties associated with inter-lane electrophoretic mobility variations.
Multi-color fluorescent detection imposes five severe constraints on the selection of dye labels, particularly for applications requiring a single excitation light source, an electrophoretic separation, and/or treatment with enzymes, e.g., automated fluorescence-based DNA sequencing. First, it is difficult to find a set of dyes whose emission spectra are spectrally resolved, since the typical emission band half-width for organic fluorescent dyes is about 40–80 nanometers (nm) and the width of available spectrum is limited by the excitation light source. Second, even if dyes with non-overlapping emission spectra are found, the set may still not be suitable if the respective fluorescent efficiencies are too low. Third, when several fluorescent dyes are used concurrently, simultaneous excitation becomes difficult because the absorption bands of the dyes are widely separated. Fourth, the charge, molecular size, and conformation of the dyes must not adversely affect the electrophoretic mobilities of the analyte. Fifth, the fluorescent dyes must be compatible with the chemistry used to create or manipulate the analyte, e.g., DNA synthesis solvents and reagents, buffers, polymerase enzymes, ligase enzymes, and the like. (See, e.g., U.S. Pat. No. 6,008,379.)
One of the limitations of such presently available technologies arises from the available pool of restriction enzymes. These produce a correspondingly limited pool of restriction sites and, therefore, fragments to be detected. Another limitation pertains to the nature of information that is discoverable, i.e., whether the identified target is present, and its relative concentration. It is not, however, readily possible to determine the relative proximity of target sites to each other under fixed or changing environmental conditions.
Fluorescence energy transfer ("FET") and fluorescence resonance energy transfer ("FRET") are distance-dependent excited state interactions in which emission of one fluorophore is coupled to the excitation of another. These processes employ two fluorescent dye molecules, one, a donor (D1), having relatively shorter wavelength excitation and emission spectra, and the other dye, an acceptor/reporter (D2), having longer wavelength excitation and emission spectra. Excitation of D1 by a light source of appropriate wavelength ultimately results in emission by D2 at its characteristic wavelength. D1 and D2 must be sufficiently proximate (within about 100 Å) to facilitate energy transfer; this can be accomplished in a number of manners (e.g., via linking to solid supports) or, in the special case of direct fluorescence energy transfer, D1 and D2 can be physically linked together (e.g., through a chain of covalently linked atoms). In general, when D1 is excited (at a shorter, higher energy wavelength) it re-emits a photon at a longer wavelength (within D1's emission spectrum), and this re-emitted photon is in turn absorbed by D2 to produce an excited state. As D2 returns to its ground state, it emits a photon of light at a wavelength characteristic of its spectrum. In radiationless energy transfer, the reporter dipole interacts or resonates with the donor dipole where the energy level difference between the fluorophores corresponds to the quantum of excitation energy. In this process, the quantum, or exciton, is transferred, which raises the electron in the reporter to a higher energy state as the photo-excited electron in the donor returns to ground state. D1 transmits its excitation energy directly to D2 through the chain of linking atoms, without D1 ever releasing a photon. After D2 absorbs this energy it returns to its ground state while emitting a photon. Conditions include that the fluorescent emission spectrum of the energy donor overlap the absorption spectrum of the energy reporter, and that the donor and reporter transition dipole orientations must be approximately parallel. Energy transfer may be detected from an increase in reporter emission or a decrease in donor emission. In either case (direct or indirect) the result of such energy transfer is that D2 can be induced to emit a photon where the initial excitation light put into the system is of a wavelength that would not normally excite D2.
Notwithstanding the available fluorescent dyes and their application in various analytical methods including simple fluorescence, FET and FRET, it has remained desired to provide new and improved fluorescent dyes, FET and FRET dye couples, multiple-color energy transfer sets and methods of their use, particularly where no purification to remove excess fluorescent marker is required to achieve a satisfactory detection signal.

Fluorescent dyes, energy transfer couples and methods


The invention provides a system and method for automatically annotating pictures in an image-capture device. The system includes an image capture system that is configured to capture an image. A memory is coupled to the image capture system and is configured to maintain a user-specific database. A processor is coupled to the memory and is configured to annotate the image with a tag based on data from the user-specific database.

One problem with current database technologies is in retrieving information from them. Creating the right search parameters is typically the key to finding the right data in a database. However, even with the right search parameters the data must be catalogued in a manner consistent with those search parameters. If the data lacks appropriate information for cataloguing, it cannot be effectively located in a search.
In photography, a user may take pictures at different times and places. Searching through the pictures one by one is inefficient and slow, so having an automated search for pictures in a database is desirable. Sometimes the picture does not conjure up a memory of where or what is in the picture, so conventional systems offer several methods for annotating pictures for database storage and search.
The first method is with the date and time of day. However, this is not a very useful search feature, as most dates are not particularly easy to recall.
Another method involves marking the position of the camera with latitude and longitude coordinates and annotating the picture with the coordinates. As with the date and time of day feature, most users are not particularly aware of their coordinates, so reference to those coordinates is not helpful.
Another method involves annotation by the user at the time the picture is taken. However, most cameras are not designed for text input, so this type of annotation is cumbersome and time consuming. Furthermore, most users do not want to pause from viewing scenery or participating in an event to enter such text.
Accordingly, what is needed is a system and method for automatically annotating images from an image-capture device, especially with information relevant to the user or easily searchable at a later time. The present invention addresses such a need.

System and method for automatically annotating images in an image-capture device


Disclosed is a method for providing an in-game messenger service comprising: storing a game program in a platform server; associating an in-game messenger program for the game program; and transmitting the in-game messenger program associated with the game program to a user terminal as the game program is transmitted from the platform server to the user terminal.

An in-game messenger is widely used for communication between users in an on-line game. A method for searching a game opponent through an instant messenger other than a game is disclosed in Korean Patent Application No. 2012-0043747 and the like. However, the existing instant messenger is actually separated from the game. Thus, when a user wants to use a messenger during game play, the user should activate a messenger window separately. Also, between different kinds of game, it is impossible to send a message through the in-game messenger.

Method and apparatus for providing in-game messenger service


An ultrasound imaging probe (204) includes a transducer array (210). The transducer array includes one or more transducer elements (212). The ultrasound imaging probe further includes an illumination component (218) and an optical imaging component (220). The ultrasound imaging probe further includes an elongated housing (302) with a long axis (304). The elongated housing includes a proximal end region (306) affixed to a handle (308) and a distal end region (310) with a tip region (312). The elongated housing houses the transducer array, the illumination component, and the optical imaging component in the distal end region.

Ultrasound (US) imaging has provided useful information about the interior characteristics (e.g., organ tissue, blood flow, other flow, etc.) of a subject or object under examination. A general ultrasound imaging system has included an ultrasound probe with a transducer array and a console. The ultrasound probe houses a transducer array, and the console includes a display monitor and a user interface. The transducer array transmits an ultrasound signal into a field of view and receives echoes produced in response to the signal interacting with structure therein. The echoes are processed, producing an image of the scanned structure, which is visually presented through the display monitor.
Endoscopic ultrasound combines ultrasonography and endoscopy. The particular type of endoscope used depends on the site in the body and the type of procedure. For example, colorectal examinations to identify cancerous and pre-cancerous regions have used a sigmoidoscope, a proctoscope, etc. with a light and an optical imager at the distal end. For the exam, the scope is inserted and used for initial visual identification of polyps or superficial cancers on the rectal wall tissue. The location of such a region of interest is determined, and the scope is removed. The US probe is then inserted to the same position for an ultrasound scan and evaluation of the region of interest.
An endoscopic probe has also been configured to also support an ultrasound probe. FIG. 1 shows a rendering of such an endoscopic probe from Olympus. In FIG. 1, an endoscopic probe 102 includes a light source 104 and an optical imager 106 at a distal end 108. The endoscopic probe 102 further includes an instrument channel 110, which extends the length of the endoscopic ultrasound probe. With this example, the endoscopic probe 102 is inserted and used as discussed above. However, rather than removing the endoscope and inserting an ultrasound probe, an ultrasound mini-probe 112 protruding from the channel 110 out of the distal end 108 is used.
Unfortunately, such probes require feeding the ultrasound mini-probe through the channel, which consumes time and may require an additional hand while keeping the light source and the optical imager directed on the target tissue of interest. Furthermore, the light source and the optical imaging component are at the distal end of the endoscopic probe. As a consequence, the ultrasound mini-probe may partially obstruct the light and view and/or it may not be possible to see what is beyond the end of the ultrasound mini-probe when the ultrasound mini-probe is installed and protruding from the channel. As such, there is an unresolved need for another approach.

US imaging probe with an US transducer array and an integrated optical imaging sub-system


A holder mechanism for holding a handheld device is provided which includes a holder base and a gripping assembly. The gripping assembly is movably mounted on the holder base. The gripping assembly includes an elastic element, a first gripping module, and a second gripping module. The elastic element has a first end fixed to the first gripping module and a second end fixed to the second gripping module. Whereby, the second gripping module can move relative to the first gripping module to grip the handheld device when the elastic element is elastically deformed to apply a resilient force to the second gripping module.

1. Field of the Invention
The instant disclosure relates to a holding device; in particular, to a holder mechanism for holding a handheld device.
2. Description of Related Art
In the recent years, handheld devices such as mobile phones and tablets have become common. Generally, when using a smart phone or a tablet PC, the user needs to hold the device in one hand and to operate it in another hand. If the handheld device is put on a table, the device is usually laid flat on the table, so that the handheld device is difficult to be read by the user. In addition, handheld devices are not only used while walking or standing, but also in receiving phone calls and navigating directions while driving via setting the device in a car or a motorbike using a handheld device holder.
Since most of the handheld device holders on the market cannot fit all handheld devices with different shapes or sizes, they have small applicability. The users need to choose a specific holder to set their hand held devices on it depending upon different types. Furthermore, previous handheld device holders have complex configurations and parts, so as to increase some operating problems for the users.


Methods and apparatus that may be utilized to reduce latency associated with encryption based on externally stored security metadata are provided. When encrypted data is accessed for the first time, a cache line containing corresponding metadata used for decryption may be placed in an internal security metadata cache. If that data is accessed again, it may be retrieved without accessing external memory, thus reducing latency. Further, if adjacent data is accessed, the cached line may contain sufficient metadata to decrypt the adjacent data. As a result, a separate operation to access metadata for the adjacent data may be avoided, thus reducing latency.

1. Field of the Invention
The present invention generally relates to data encryption and, more particularly, to methods and apparatus for updating parameters used for encryption, such as version control parameters.
2. Description of the Related Art
A system on a chip (SOC) generally includes one or more integrated processor cores, some type of embedded memory, such as a cache shared between the processors cores, and peripheral interfaces, such as memory control components and external bus interfaces, on a single chip to form a complete (or nearly complete) system. The use of cache memory hierarchies is well established to improve a processor performance by reducing and/or eliminating read access requests to external memory.
As part of an enhanced security feature, some SOCs encrypt some portions of data prior to storing it in external memory. Adding such encryption to an SOC may add valuable benefits, such as preventing a hacker from obtaining instructions of a copyrighted program, such as a video game, or data that may be used to determine such instructions through reverse engineering. When the encrypted data is subsequently retrieved from external memory, it must first be decrypted before it can be used by the processor cores.
Certain types of security information (referred to as metadata) may be employed in an effort to enhance security. For example, an integrity check value may be calculated when encrypted data is written out to external memory and stored. This stored integrity value may be compared against an integrity value calculated when retrieving the encrypted data, with a mismatch indicating the encrypted data has been tampered with. Further, a security version value may be used to affect encryption in some manner. Changing this security version value often (e.g., on every encrypted write to external memory) may prevent unauthorized users (e.g., hackers) from gaining knowledge about security by monitoring data traffic.
In some cases, this security metadata itself may be encrypted and stored externally. Because external memory resources are typically much greater than internal memory resources, storing such metadata externally may allow security to be applied to a much larger memory space than if such metadata was only stored internally. However, in such cases, before encrypted data can be decrypted and validated, the corresponding security metadata used for the encryption must be retrieved and decrypted. As a result, while security metadata may lead to enhanced security, storing this security metadata externally may result in additional latency when retrieving the corresponding encrypted data.
Accordingly, what is needed is a mechanism for reducing latency associated with externally stored security metadata.

Secure memory caching structures for data, integrity and version values

International Business Machines Corporaiton


A system facilitates identifying service providers capable of performing services for users and enable the pricing and scheduling of services to be performed by the service providers. A user submits a service request including a service description and optionally service constraints such as a required service location and service time. The system matches the service request with service providers potentially suitable for performing the requested service. The system sends bid solicitations to matched service providers, who may then respond with requests for additional information or bids. The bids are presented to the user, who then selects the bid best suited for his or her needs. The service provider associated with the selected bid is notified of the user's selection, thereby scheduling the service. A social graph associated with the user may be used to assist users in selecting bids.

The invention relates generally to the field of internet search, and in particular, to systems and methods for identifying services required by users, soliciting and accepting bids for services from appropriate service providers, scheduling the performance of services by service providers, and rating the performance of service providers.
Consumers often hire service providers to perform tasks. For example, a consumer might hire a babysitter to care for a child, a plumber to fix a leaking faucet, or a general contractor to construct and install kitchen cabinets. In general, a service provider is any person, company, organization, or other entity that offers services to consumers. A service provider may provide only services, for example a babysitter or a personal assistant, or provide services in conjunction with goods, such as a contractor that installs cabinets or a plumber that replaces pipes. For this application, the term consumer may refer to any entity that requests a service from a service provider, including individual users, companies, organizations and government agencies.
Previously, consumers looking for service providers have utilized telephone directories, lists of recommended businesses from professional organizations, such as the Chamber of Commerce or the Better Business Bureau, or word-of-mouth recommendations from friends, family, colleagues, and business associates. More recently, online versions of these types of directories have become available. Previously, three broad categories of online local search have emerged to date:
The first major category of online local search is the online directory, which are web sites or electronic equivalents of telephone directories and other types of business directories. These online directories typically include features such as searching or browsing by key words or categories. Electronic directories are most useful when consumers already have a business category or business name in mind.
The second major category of online local search is rating and review web sites, which are analogous to lists of recommended businesses and word-of-mouth recommendations. These web sites provide editor-generated or user-generated ratings and reviews of businesses, which act as a form of decision support for consumers who generally do not have first-hand familiarity with the business but want to gauge the quality of their services to determine if they want to become a customer.
The third major category of online local search is lead generation sites. These sites accept requests for services from consumers and broker them out to potential service providers. The service providers must then contact the interested consumers directly to attempt to win their business.
All of the previous offline and online local search systems fail to meet numerous consumer needs. First, consumers often do not know the proper name of the service category or the occupation of the person needed to complete a given task. In these cases, the local search options available today provide little value because the consumer lacks the knowledge required to perform an effective search.
Second, many consumers have specific time and/or location requirements for services. For example, a consumer may require a babysitter for a specific day and time and at their home or relatively nearby. Prior local search systems and online directories do not typically include any time and/or location specific constraints when identifying service providers. Thus, consumers using these prior systems cannot efficiently determine which locally-based service provider(s) are available to complete the service at the desired place and time. Instead, consumers typically must generate a list of potential service providers and then call or email each one of them individually to determine their availability. This is a time-consuming and tedious process that represents a significant burden to the consumer.
Third, consumers do not have a way of knowing which service provider will offer the best possible value because they lack up-front pricing information from prospective service providers. To determine pricing, consumers generally must visit each service provider's web site or call or email each of them separately. This also is a time-consuming and tedious process that represents a significant burden to the consumer.
Fourth, consumers often struggle to decide which service provider to choose when faced with many possibilities. The primary existing mechanism in internet local search to help consumers decide on a prospective service provider is the sharing of ratings and reviews left by other customers. However, this method suffers from a high number of false or biased ratings (e.g., negative ratings left by competitors or positive ratings left by the business owner's friends or the owner himself) which greatly undermine their value. Furthermore, there is no validation that a reviewer ever used the service provider and has first-hand knowledge of the service provider, thereby diminishing the value of the review.
Additionally, all of these prior types of local search systems and online directories fail in several respects to meet the needs of service providers.
First, service providers do not have a way to be connected with potential customers who want to hire them at the time the service provider is available to work. Many service providers have busy schedules but have gaps in their schedules during which they could provide additional services. They currently lack a good way to fill these gaps which results in lower work utilization and productivity. By contrast, service providers have little interest in being contacted by consumers who want a service initiated at a time when the service provider is unavailable to work due to prior commitments or because the requested time is outside their standard working hours. Furthermore, casual or part-time service providers may have very limited schedules for accepting services. With prior systems, it is very difficult for these types of service providers to find customers seeking services during the hours they work.
Second, service providers face difficulty in making potential customers aware of their business. They spend great sums of money on local advertising, but much of this is wasted as potential customers ignore the ads or choose a competitor instead. The lead generation sites are also an inefficient source of spending because service providers pay for each service lead, rather than for services they provide due to the lead. Furthermore, multiple service providers pay lead generation fees for a single lead, and at most, only one of them will win the service.

Identifying, soliciting, selecting and scheduling service providers


Novel event-processing operators are provided. These novel operators can be advantageously utilized in implementing event processors and event-processing systems. The novel event-processing operators include operators for event filtering by clustering, operators for event partitioning by classification, operators for event abstraction by hypothesis testing, and operators for event filtering by point estimation.

Many business enterprises use computer systems to monitor and process business activities and transactions. Business entities that handle complex transactions and activities, in particular, often employ distributed computer systems.
Conventional database systems and business data processing algorithms emphasize a passive repository storing a large collection of data elements and perform human initiated queries and transactions on such repository. Such conventional technology emphasizes the importance of the current state of the data. Hence, current values of the data elements can be easy to obtain, while previous values can only be found by decoding database log files. Such conventional technology also treats notifications and triggers with low priority, and these constructs are added mostly as an after thought to the current systems. Conventional technology also assumes that data elements are synchronized and that queries have exact answers. In many stream-oriented applications, data arrives asynchronously and answers must be computed with incomplete information.
There is a substantial class of applications where data takes the form of continuous data streams rather than finite stored data sets, and where clients require long-running continuous queries rather than one-time queries. This class of applications include network monitoring, telecommunication data management, sensor networks, manufacturing, and others. The traditional database systems and business data processing algorithms are not well equipped to support these kinds of applications. Business enterprises implement event processing systems including event processors to support these kinds of applications.


An artificial eye includes a generally spherically shaped container including a substantially hemispherical posterior portion, a substantially hemispherical anterior portion and a fastener for attaching the posterior portion to the anterior portion. The artificial eye includes functional counterparts to the anterior and posterior chambers of the human eye. Within these chambers are fluids which mimic the characteristics of the aqueous and vitreous humors in the human eye. Protective eyewear is tested by placing the eyewear between the artificial eye and a source of radiation. Radiation is directed through the protective eyewear and then through the artificial eye. The radiation is then received by a sensing device such as a charged couple device (CCD) camera or optometer. The resulting image is then evaluated.

The invention relates in general to an artificial human eye and in particular to an artificial human eye for testing the effectiveness of protective eyewear against harmful radiation.
Attempts have been made previously to simulate the function of the human eye with models. U.S. Pat. No. 1,630,944, issued to L. R. Ingersoll on May 31, 1927 includes lenses to represent the cornea and lens, and a curved metal plate which serves as the retina. A single water filled chamber represents both the aqueous and vitreous humors of the eye. An external image is projected through the lenses and water onto the metal plate. U.S. Pat. No. 2,068,950, issued to F. Hamilton on Jan. 26, 1937 is directed to an artificial eye with a single lens which represents the human cornea. Two curved sections form a hollow shell which approximates the shape of the human eye. An opening in one section houses the lens. In a second embodiment, a solid glass portion which is nearly a complete sphere approximates the shape of the human eye. A second glass portion completes the sphere and constitutes the lens. However, the above-described artificial eyes do not provide a satisfactory device with the proper refractive indices and power to simulate the form and function of a human eye.
There have been two main methods for testing the effectiveness of protection for shielding the human eye against harmful radiation. One method uses laboratory animals such as rabbits and monkeys. Using animals is disadvantageous because it is costly and time consuming to house and train the animals. Furthermore it is painful to the animals and can be a controversial public relations issue. A second method utilizes extrapolated data from tests on human subjects in which the radiation strength is well below a hazardous level. This method is of limited value because there is always the question of unexpected effects that may arise as the level of radiation increases. This uncertainty is of particular concern when the protective properties of the eyewear is not a linear function of the intensity of the radiation.
It is an object of the present invention to provide an artificial eye that is an enlarged, scaled functional replica of the human eye.
It is another object of the present invention to provide an artificial eye including fluids which mimic the aqueous and vitreous humors of the human eye.
It is yet another object of the present invention to provide an artificial eye including variable apertures and lenses which mimic the human pupil, cornea and lens.
It is still another object of the present invention to provide an artificial eye which can simulate characteristics of the human eye such as near or far sightedness and age.
It is a further object of the invention to provide an apparatus for testing protective eyewear which precludes the use of humans and animals, is less costly, and more accurate than previous designs.
These and other objects of the invention are achieved by an artificial eye comprising a generally spherically shaped container; a lens holder removably disposed in a first opening in the container; a first fluid disposed in the container; and a second fluid disposed in the lens holder.
The generally spherically shaped container comprises a substantially hemispherical posterior portion made of a substantially transparent material, a substantially hemispherical anterior portion made of a substantially opaque material and a fastener for attaching the posterior portion to the anterior portion.
Preferably, the substantially transparent material comprises plexiglass, the substantially opaque material comprises one of aluminum and stainless steel and the fastener comprises two bands of aluminum.
In a preferred embodiment, the interior surface of the substantially hemispherical posterior portion is frosted.
Another aspect of the invention is a test apparatus comprising a radiation source; a device to be tested disposed in a path of radiation from the radiation source; an artificial eye disposed in a path of radiation from the device to be tested; an image receiving device for receiving the image created in the artificial eye; and an image processor for processing an electronic image from the image receiving device into a human readable image.
Preferably, the image receiving device is one of a charged couple device camera and an optometer.
Further objects, features and advantages of the invention will become apparent from the following detailed description taken in conjunction with the drawing.

The United States of America as represented by the Secretary of the Navy


In a laser beam X-Y scanning system for use, as for example, in turbid media such as sea water; the laser light reflected from objects is received by an image receiving device or detector such as a photomultiplier tube (PMT). The intensity level of the reflected light is maintained at an intensity level within the dynamic range of the image receiving device by controlling the effective intensity of the laser beam by varying the density of a plurality of series positioned variable neutral density filters positioned between the laser beam generator and the object to be illuminated or the illuminated object and the image receiving device. The light density of each filter is determined by real time environmental conditions and the instantaneous position of the laser light source relative to the object from which the laser light is reflected to the image receiver. The density of each of the plurality of filters is controlled by a computer.

The invention relates in general to automatic gain control of a system utilizing measured environment parameters to define gain control to be applied, and more particularly to a laser scanning system which automatically controls the laser light intensity directed to an object to be detected in such a manner that the laser light reflected from that object received by the receiver is maintained within the dynamic (gray scale detection range of the receiver.
Specialized viewing systems can greatly enhance the observation of objects in turbid media; For example, such systems are useful in seawater for salvage and recovery operations or for object detection.
With the advent of the laser, relatively high powered directed illumination of a scene for imaging purposes becomes realizable.
Turbid media viewing systems utilizing laser technology are designed to avoid the deleterious effects of scattering, that is, to separate information containing light from non-information containing light. Conventionally, a method of accomplishing this is to separate the light source from the receiver. The greater the separation, the less scattered light is detected by the receiver. Usually, the source and receiver are as far apart as is permitted by the size of the vehicle upon which they are mounted.
An underwater viewing system can be found in U.S. Pat. No. 4,707,128 by inventor Bryan W. Coles. In this system an emitter, such as a pulsed laser, emits a short pulse of light which travels to a beam splitter where part of the light is transmitted and part is deflected. The transmitted portion passes through optics and is deflected by an X-Y scanning element in such a manner that a portion of an object is illuminated in a point-by-point manner. Light reflected from the object travels back along a path that is coaxial with the path of the transmitted light pulse striking the scanning elements and the beam splitter. The return light deflected by the beam splitter is received by a light sensor, such as a photomultiplier tube.
Other prior art systems consists of similar devices in which an image is manually adjusted, either real-time or based on empirical charts, to achieve an acceptable image at the receiving device.
Alternatively, the prior art also consists of using Automatic Gain Control (AGC), which consists of feeding back an error signal from the received image to adjust the receiver gain to within its dynamic (gray scale) range. This type of derived AGC relies on a historical average for a baseline, requiring a receiving device with a larger detector dynamic range than required of the system of the instant invention to accommodate potential signal drop-outs or spikes.
In some of these state of the art viewing systems, manual adjustments are made consisting of adjusting the gain on a monitor displaying the image in real-time to obtain a picture with discernable intensity levels. This method of maintaining a suitable received image requires the presence of a human operator constantly making adjustments for maximum image quality.
Another method of maintaining a received light image in the dynamic range of the receiving device is through the use of error signal feedback. In this method, the average value of the scene being imaged is fed back to the receiver gain controller. The receiver gain is controlled such that the average value is maintained within the receiver dynamic range. The time constant on such a prior art device can be preset to roughly accommodate the scan angle of the device.
Neither of these two methods incorporates any time dependency in the gain function.
There has not been an automatic means for real time control of the light output intensity of a laser light scanning system in which the intensity of reflected light from an illuminated object is maintained within the dynamic light intensity range of the image receiver until the emergence of the instant invention.

Method and apparatus for faithful gray scale representation of under water laser images


A two-walled, dual chamber, inflator for inflation of an automotive airbag in the event of a collision is provided. The inflator includes a simplified housing with two internal chambers, including a central chamber and a coaxial outer chamber. The central chamber houses both the solid fuel gas generant bodies and a electrical igniter having a reliable single-stage ignition train in direct contact with the generant bed. The single-stage igniter includes a resistance wire submersed in the generant bed along a convoluted path. Multiple points of direct contact are established between the igniter wire and gas generant over a substantial portion of the generant bed, which leads to more uniform and efficient ignition of the gas generant. To get sufficient surface area for the generant to contact the igniter wire, the gas generant bodies are formed in relatively small sizes of about 0.05 inch or less, which, in turn, limits the selection of gas generant materials to those having low burn rates of about 0.625 inch/second or less to be effective. The outer chamber contains a filter for cooling the generated gas and collecting entrained particulate residues prior to venting into the airbag cushion. A one-walled, single chamber, airbag inflator is also provided. The onewalled inflator includes a further simplified housing with only one internal chamber formed inside the outermost wall and no internal side walls dividing the interior into multiple chambers. All components are housed within the single chamber, including the single-stage direct electrical igniter, the small sized gas generant bodies, and the filter which is optional.

An inflatable airbag restraint system is a safety device for protecting automotive vehicle occupants in a collision. In such a system, an airbag is stowed in an uninflated and folded condition in a covered compartment located on the steering wheel or behind the instrument panel. The open mouth of the airbag is situated around gas outlet ports of a gas generator or inflator used to inflate the airbag. In the event of a collision, an on-board crash sensor, detecting the sudden deceleration of the vehicle indicative of the onset of the collision, immediately sends an electric signal to an ignition system located in the inflator. The ignition system fires and initiates combustion of the gas generant also housed in the inflator, which, upon burning, rapidly produces large volumes of high pressure gas which are directed into a filtering and cooling system and vented into the folded airbag. The airbag is caused to expand and deploy in a matter of milliseconds out of its covered compartment into position in front of the vehicle occupants to effectively cushion the occupants against injury-causing impact with interior structures of the vehicle.
The operational requirements of airbag inflators are very demanding. First, the inflator must remain operative for the life of the vehicle. Next, upon activation, the inflator must produce large volumes of relatively cool, non-toxic, and non-corrosive gas in a matter of 30 to 40 milliseconds in order to inflate and deploy the airbag in a timely fashion for effective occupant cushioning. Many forms of driver's side, solid fuel, airbag inflators have been proposed. Recent emphasis on weight reduction has created the need for lighter weight airbag inflators. U.S. Pat. No. 4,547,342 (Adams et al.) and U.S. Pat. No. 4,561,675 (Adams et al.) disclose a few light weight, three-chambered, aluminum inflators which are currently practiced in the art. A similar inflator is shown in U.S. Pat. No. 5,419,578 (Storey et al.).
Typical prior art airbag inflators have a cylindrical housing or canister with three distinct chambers formed inside an outermost wall in the divided spaces created between two inner cylindrical side walls and the outermost wall. In general, there is a central wall between the central ignition system and the encircling solid gas generant material, and another wall spaced outside the central wall between the gas generating material and the encircling filter assembly. The gas produced must flow through ports in both internal walls before passing through diffusion ports in the outermost wall into the airbag. Each ported internal wall and separate chamber adds complexity, size, weight, thermal and fluid flow inefficiencies, and cost to the inflators.
Adding further complexity to the prior art inflators is a typical two-stage ignition system housed inside the central ignition chamber. In the first stage, an electrically activatable squib is used which is filled with a primary igniter charge, for example, powdered ZrKCIO.sub.4. The squib protrudes in a central ignition chamber from the bottom of the inflator. A pair of leads extend from the squib outside the inflator for connection to the on-board crash sensor circuit. The leads are bridged within the squib by a resistance wire embedded in the primary charge. The second stage uses a igniter cup having a recessed bottom which is filled with a secondary igniter charge, for example, powdered BKNO.sub.3, situated on top of the squib. In operation, the electric current sent from the on-board crash sensor is passed into the squib to ignite the primary charge through resistive heating. Upon ignition, the flame and hot gas produced ignites the secondary igniter charge, bursting the cup and releasing flame and hot gas through the ignition chamber ports into the adjoining combustion chamber for ignition of the gas generant and production of the inflation gas for airbag deployment.
Each ignition stage, however, adds complexity and cost to the inflator. Also, the inflator becomes less reliable, since a number of possible ignition failure points exist along the ignition train. For instance, the igniter charges are susceptible to atmospheric moisture during manufacture and inflator assembly and storage. Moisture contamination can alter their ignition and combustion properties, which could lead to a failure in one or both of the ignition stages and cause a catastrophic inflator misfire. Handling by assembly workers of multiple ignition components might also lead to contamination, dangerous premature firing, and faulty assembly.
Another disadvantage of the two-stage ignition system is that it contributes to the generation of undesirable effluents, such as CO, NH.sub.3 and NO.sub.x, resulting from incomplete and inefficient combustion of the gas generant materials. The central location of the ignition system tends to inhibit uniform and efficient combustion of the gas generant bodies within the combustion chamber. This is because the ignition blast must propagate from a limited number of ignition chamber ports radially outward over the entire gas generant bed. Gas generant material located relatively far way from the ignition chamber ports is ignited at a later time than the material located adjacent those ports. When the generant is ignited in stages in this manner, it results in low pressure burning which is undesirable.
Ignition blast propagation problems are ameliorated somewhat when standard sodium azide gas generants pellets are employed. Sodium azide fuels due to their fast burn rates (i.e., about 0.9-1.0 inch per second) need only be pressed into relatively large sized pellets in order to burn out and produce gas within the desired time for effective deployment of the airbag. With the larger sized pellets packed within the combustion chamber, many voids are created in the generant bed which provide channels through which the ignition blast can rapidly travel.
Recently, it has been proposed to use gas generants with slower burn rates than sodium azide fuels. This would allow the selection of a wider variety of gas generants for use in airbag inflators, some of which have advantageous properties over sodium azide, such as lower toxicity and easier disposal. Such generants must be compacted into much smaller sized bodies in order to burn out at quick enough rates to be effective to inflate the airbag in a timely manner. However, upon loading of such bodies in the combustion chamber, they become tightly packed together, creating minimal voids in the chamber. Consequently, the high packing density tends to block the central ignition blast from traveling radially outward throughout the gas generant bed, thereby making it difficult to uniformly ignite the gas generant bodies. This tends to promote stagewise burning, leading to inefficient combustion, increased effluents, and gas production outside the effective time.
A simpler single-stage direct electrical ignition system for an airbag inflator is disclosed in U.S. Pat. No. 3,606,377 (Martin) wherein a resistance wire is axially embedded along the length of an elongated molded body of a solid pyrotechnic gas generant. The opposite ends of the wire extend from the opposite ends of the gas generant body and are connected to the electrical circuit of the vehicle crash sensor. However, there are problems associated with embedding an igniter wire in a gas generant body. The wire may become damaged when molding the gas generant body around the wire which could go unnoticed during inflator assembly. Damage to the igniter wire would prevent the current sent from the crash sensor circuit from being delivered, and in a collision, the igniter wire would fail to ignite the gas generant, resulting in inflator failure and no inflation and deployment of the airbag, which, in turn, could cause catastrophic injury to the vehicle occupant.
What is needed is a simpler airbag inflator containing an improved ignition system which is easier to assemble, simpler in construction, safer, more reliable and more efficient in operation, and which can be used with smaller bodies of low burn rate gas generants.

Airbag inflator with direct electrical ignition for small sized gas generant bodies