A method is set forth for calculating an expected Echo Return Loss Enhancement (ERLE) in an echo canceller. The expected ERLE is used to control the adaptation step of an adaptive filter in the echo canceller. Also, a novel echo canceller is set forth where the adaptation step of its adaptive filter is controlled based on the expected ERLE.

The signal path between two telephones, involving a call other than a local one, requires amplification using a four-wire circuit. The cost and cabling required discourages extending a four-wire trunk circuit to a subscriber's premises from the local exchange. For this reason, the four-wire trunk circuits are coupled to two-wire local circuits, using a device called a hybrid.
Hybrid echo, the primary source of echo generated from the public-switched telephone network (PSTN) is created as voice signals are transmitted across the network via the hybrid connection at the two-wire/four-wire PSTN conversion points.
Unfortunately, the hybrid is by nature a leaky device. As voice signals pass from the four-wire to the two-wire portion of the network, the energy in the four-wire section is reflected back, creating an echo of the speech signal. Provided that the total round-trip delay occurs within just a few milliseconds, the echo results in a user perception that the call is 'live' by adding sidetone, thereby making a positive contribution to the quality of the call.
In cases where the total network delay exceeds 36 ms, however, the positive benefits disappear, and intrusive echo results. The actual amount of signal that is reflected back depends on how well the balance circuit of the hybrid matches the two-wire line. In the vast majority of cases, the match is poor, resulting in a considerable level of signal being reflected back.
The effective removal of hybrid echo is one key to maintaining and improving perceived voice quality on a call. This has led to intensive research into the area of echo cancellation, with the aim of providing solutions that can reduce echo from hybrids. By employing the results of this research, the overall speech quality has significantly improved.
It is known in the art to employ adaptive filtering to address hybrid echo cancellation. In Normalized Least Mean Square (NLMS) adaptive filtering, adaptive filter coefficients are used to map the hybrids in the signal path. Using these coefficients, the NLMS adaptive filter cancels signal reflections from the hybrids in the signal path. To adapt and stabilize the adaptive coefficients so that the Echo Return Loss Enhancement (ERLE) is maximized for all hybrids, the adaptation step of the NLMS algorithm is varied.
Under ideal conditions, a generally acceptable convergence time requires that the echo canceller achieve 27 dB of ERLE (Echo Return Loss Enhancement) in 0.5 sec. Once the coefficients are converged, the echo is canceled from the input signal.
It is an object of an aspect of the present invention to minimize the convergence time of the adaptive filter for different hybrids in the signal path and to obtain as much ERLE possible under different line conditions.

Method of adaptation step control in echo cancellers


In an approach for suggesting an item to pack, a processor receives an indication that a user is packing a first item of luggage, wherein the indication includes information about a trip. A processor generates a packing list based on the information about the trip. A processor receives a request to link the first item of luggage and a second item of luggage for the trip. A processor links the first and second items of luggage such that contents of each item of luggage are jointly compared to the packing list. A processor receives, via a short-range point-to-point communication reader of the first item of luggage, a signal from a short-range point-to-point communication device operably affixed to a first item. A processor identifies the first item based on the signal. A processor determines that the first item is an item of the packing list.

The present invention relates generally to the field of traveling and packing, and more particularly to utilizing short-range point-to-point communication to inventory items in luggage, provide recommendations, and to generate alerts.
The Internet of Things (IoT) is the network of physical objects or "things" embedded with electronics, software, sensors, and network connectivity, which enables these objects to collect and exchange data.
Short-range point-to-point communication technologies include, for example radio-frequency identification (RFID) and near field communication (NFC). Other similar technologies include Bluetooth®.

Luggage contents recommendations and tracking

International Business Machines Corporation


Stabilized carrier recovery is achieved even at the time of a low C/N ratio by measuring the phase of a signal and controlling VCO or NCO (Numerical Controlled Oscillator) using only a period having few constellation points. At this time, false lock phenomenon is avoided as follows. That is, relatively short SYNC modulated by an already-known pattern is entered into a modulation wave, VCO or NCO oscillation frequency is swept in a wide range and sweep is stopped at a frequency in which the SYNC can be received, thereby carrying out coarse control AFC. Further, a period having long to some extent, having few constellation points is provided in the modulation wave and then, a difference between the frequency of a received modulated signal and a local oscillation signal of VCO or NCO is obtained in this period. This frequency difference is analyzed according to the phase differential function method, self-correlation function method or count method, and the VCO or NCO is controlled based on this result of analysis.

The present invention relates to an AFC circuit, a carrier recovery circuit and a receiver for use in satellite digital television broadcasting and more particularly to an AFC circuit, a carrier recovery circuit and a receiver for regenerating a carrier even at the time of low C/N ratio.
For digital transmission through a satellite, hierarchical transmission method capable of data transmission to some extent even at the time of a low C/N ratio by adaptive transmission by time division based on modulation method having different numbers of constellation points by considering a deterioration of the C/N ratio due to rain attenuation or the like has been invented. In such a transmission method, it is very difficult to obtain a reference signal necessary for carrier recovery from a period of modulation wave having many constellation points at the time of low C/N ratio, and therefore, a carrier recovery method which is an ordinary carrier recovery method for continuously regenerating the carrier, cannot be used.
Accordingly, an object of the present invention is to achieve carrier recovery by disposing periodically a modulated signal period with few constellation points which is modulated by, for example, BPSK modulation method or QPSK modulation method and from which a reference carrier signal having a considerable CN rate can be obtained, and fetching out phase/frequency error information periodically. Further, because, according to a method for observing a phase error signal periodically, with a frequency of a predetermined period, the same phase error signal is obtained, so-called false lock phenomenon in which the frequency is apparently synchronized with a different frequency from its proper carrier frequency occurs. To avoid this phenomenon, a modulated signal with few constellation points which is modulated by, for example, BPSK modulation method or QPSK modulation method is set at a predetermined interval and in the pseudo synchronizing state, a frequency of a difference from the proper carrier frequency is observed by using such a fact that the reception signal phase is rotated in a predetermined direction so as to control the VCO (Voltage Controlled Oscillator) thereby making it possible to synchronize with the proper frequency. In the modulation period having few constellation points, detection of the pseudo synchronizing state and synchronization with a desired frequency are enabled using a statistical characteristic of an observed signal.
In a conventional transmission method of transmitting a modulated signal having many constellation points continuously or a method in which the number of constellation points is changed by time division system, if carrier recovery is carried out continuously, when the C/N ratio drops, a stabilized carrier recovery signal cannot be obtained in a modulation period having many constellation points. For this reason, even if a modulated signal having few constellation points exists, stable demodulation is disabled.
Further, in a method for carrying out carrier recovery periodically using only a period having a few constellation points for such a modulated signal, there is a problem that false lock occurs by observing the phase periodically. Therefore, a wide capture range cannot be achieved. Thus, because a very high frequency stabilization accuracy is demanded in the transmission system containing the frequency conversion portion, the receiver device becomes very expensive.
For the reason, according to the method for transmitting modulated signals having different numbers of constellation points in time division system, if the conventional carrier recovery system is utilized, the carrier recovery is disabled when the C/N ratio is low.
Then, although a method for controlling the VCO or NCO (Numerical Controlled Oscillator) can be considered by measuring the phase with only a period having a few constellation points, there is a problem that a wide capture range cannot be achieved because of false lock phenomenon caused by observing the phase periodically.
The present invention has been achieved in viewpoints of the above problems and therefore it is an object of the invention to provide an AFC circuit capable of regenerating a carrier signal synchronous with the inputted signal in terms of the frequency while preventing an occurrence of false lock even when a reference signal period or a modulated signal period having a few constellation points which can be used for carrier recovery, contained in an input signal, is short or even when noise is mixed in the inputted signal.
Another object of the invention is to provide a carrier recovery circuit capable of regenerating the carrier signal stably in a wide capture range by transmitting modulations signal having different numbers of constellation points by time-division system and carrying out carrier synchronization using phase and frequency error information obtained periodically even if the C/N ratio is low when a modulated signal is received and regenerated.
Still another object of the invention is to provide a receiver device capable of regenerating information contained in digitally modulated signal by carrying out carrier synchronization using phase and frequency error information obtained periodically and regenerating the carrier signal stably in a wide capture range even if the C/N ratio is low when digitally modulated signal provided with a reference signal period or digitally modulated signal period having a few constellation points to be useful for carrier recovery at a predetermined time interval is received and regenerated.
To achieve the above object, the AFC circuit for detecting a frequency difference between two inputted signals and zeroing said frequency difference between the inputted signals according to the detection result, comprises: a frequency difference detecting portion for detecting a phase difference between the inputted signals and generating a frequency correction signal according to the phase difference or a time differential value of the phase difference; and a frequency difference correcting portion for rotating the phase of the inputted signal according to the frequency correction signal outputted from the frequency difference detecting portion so as to zero the frequency difference between the inputted signals.
In the AFC circuit for detecting a frequency difference between two inputted signals and zeroing the frequency difference between the inputted signals according to the detection result, a frequency difference detecting portion detects a phase difference between the inputted signals and generates a frequency correction signal according to the phase difference or a time differential value of the phase difference and a frequency difference correcting portion rotates phase of the inputted signals according to the frequency correction signal outputted from the frequency difference detecting portion so as to zero the frequency difference between the inputted signals. As a result, even when the reference signal period modulated signal period having few constellation points which is usable for regenerating a carrier contained in the inputted signals is short or even when noise is mixed in the inputted signals, a carrier signal synchronous with the inputted signals is regenerated while preventing an occurrence of false lock.
Another feature of the invention is an AFC circuit for detecting a frequency difference between two inputted signals and zeroing said frequency difference between the inputted signals according to the detection result, the AFC circuit comprising: a correlation computing portion for detecting a phase difference between the inputted signals and computing an autocorrelation coefficient of the phase difference; and a frequency difference correcting portion for counting a number of peaks in a waveform of the autocorrelation coefficient obtained by the correlation computing portion and rotating phase of the inputted signals according to the count result so as to zero the frequency difference between the inputted signals.
In the AFC circuit in the preceding paragraph for detecting a frequency difference between two inputted signals and zeroing the frequency difference between the inputted signals according to the detection result, a correlation computing portion detects a phase difference between the inputted signals and computes an autocorrelation coefficient of the phase difference and a frequency difference correcting portion counts the number of peaks in a waveform of the autocorrelation coefficient obtained by the correlation computing portion and rotates phase of the inputted signals according to the count result so as to zero the frequency difference between the inputted signals. As a result, even when the reference signal period or modulated signal period having few constellation points which is usable for regenerating a carrier contained in the inputted signal is short or even when noise is mixed in the inputted signal, a carrier signal synchronous with the inputted signal is regenerated while preventing an occurrence of false lock.
Another feature of the invention is an AFC circuit for detecting a frequency difference between two inputted signals and zeroing said frequency difference between the inputted signals according to the detection result, the AFC circuit comprising: a correlation computing portion for detecting a phase difference between the inputted signals and computing an autocorrelation coefficient of a waveform varying in time of the phase difference; and a frequency difference correcting portion for obtaining an average period of a periodic waveform appearing in a waveform of the autocorrelation coefficient obtained by the correlation computing portion and rotating a phase between the inputted signals according to the average period so as to zero the frequency difference of the inputted signals.
In the last described AFC circuit for detecting a frequency difference between two inputted signals and zeroing the frequency difference between the inputted signals according to the detection result, a correlation computing portion detects a phase difference between the inputted signals and computes an autocorrelation coefficient of a waveform varying in time of the phase difference and a frequency difference correcting portion obtains an average period of periodic waveform appearing in a waveform in the autocorrelation coefficient obtained by the correlation computing portion and rotates a phase between the inputted signals according to the average period so as to zero the frequency difference of the inputted signals. As a result, even when the reference signal period or modulated signal period having few constellation points which is usable for regenerating a carrier contained in the inputted signal is short or even when noise is mixed in the inputted signal, a carrier signal synchronous with the inputted signal is regenerated while preventing an occurrence of false lock.
A further feature of the present invention is an AFC circuit for detecting a frequency difference between two inputted signals and zeroing said frequency difference between the inputted signals according to the detection result, the AFC circuit comprising: a region determining portion for detecting a phase difference between the inputted signals and determining which region each signal point is included in according to the phase difference; and a frequency difference correcting portion for counting a determination result of the region determining portion for each phase and for each determining region rotated at a rotation speed corresponding to a set frequency, and rotating phase of the inputted signals according to the count result so as to zero the frequency difference between the inputted signals.
In the last described AFC circuit for detecting a frequency difference between two inputted signals and zeroing the frequency difference between the inputted signals according to the detection result, a region determining portion detects a phase difference between the inputted signals and determines which region each signal point is included in according to the phase difference and a frequency difference correcting portion counts a determination result of the region determining portion for each phase and for each determining region rotated at a rotation speed corresponding to a set frequency and rotates phase of the inputted signals according to the count result so as to zero the frequency difference between the inputted signals. As a result, even when the synchronization period for the inputted signal is short or even when noise is mixed in the inputted signal, a carrier signal synchronous with the inputted signal is regenerated while preventing an occurrence of false lock.
A further feature of the invention is a carrier recovery circuit for regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, the circuit comprising: a frequency difference detecting portion for detecting a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal, and generating a frequency correction signal according to the phase difference or a differential value of the phase difference; and a frequency difference correcting portion for controlling a frequency of the regeneration carrier signal according to the frequency correction signal outputted from the frequency difference detecting portion so as to zero a frequency difference between the reception signal and the regeneration carrier signal.
In the carrier recovery circuit for regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, a frequency difference detecting portion detects a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal and generates a frequency correction signal according to the phase difference or a differential value of the phase difference and a frequency difference correcting portion controls a frequency of the regenerated carrier signal according to the frequency correction signal outputted from the frequency difference detecting portion so as to zero a frequency difference between the reception signal and the regenerated carrier signal. As a result, upon transmitting a modulated signal having different numbers of constellation points by time division system and receiving the signal, even when the C/N ratio is low, the carrier synchronization is carried out using information of the phase and frequency obtained periodically, so that the carrier signal is regenerated stably in a wide capture range.
Yet another feature of the invention is a carrier recovery circuit regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, the circuit comprising: a correlation computing portion for detecting a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal so as to compute autocorrelation coefficients of the phase difference; and a frequency difference correcting portion for counting peaks of the waveform of the autocorrelation coefficient waveform obtained by the correlation computing portion and controlling a frequency of the regenerated carrier signal according to the count result so as to zero the frequency difference between the reception signal and the regenerated carrier signal.
In the last described carrier recovery circuit for regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, a correlation computing portion detects a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal so as to compute autocorrelation coefficients of the phase difference and a frequency difference correcting portion counts peaks of a waveform of the autocorrelation coefficient obtained by the correlation computing portion and controls frequency of the regeneration carrier signal according to the result so as to zero the frequency difference between the reception signal and the regenerated carrier signal. As a result, upon transmitting a modulated signal having different numbers of constellation points by time division system and receiving the signal, even when the C/N ratio is low, the carrier synchronization is carried out using information of the phase and frequency obtained periodically, so that the carrier signal is regenerated stably in a wide capture range.
A further feature of the invention is a carrier recovery circuit for regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, the circuit comprising: a correlation computing portion for detecting a phase difference between the regenerated carrier signal and the reception signal from the I baseband signal and the Q baseband signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal so as to compute autocorrelation coefficients of the phase difference; and a frequency difference correcting portion for obtaining an average period of a periodic waveform appearing in a waveform of the autocorrelation coefficient obtained by the correlation computing portion, and controlling a frequency of the regenerated carrier signal based on the average period so as to zero the frequency difference between the reception signal and the regenerated carrier signal.
In the last described carrier recovery circuit for regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, a correlation computing portion detects a phase difference between the regenerated carrier signal and the reception signal from the I baseband signal and the Q baseband signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal so as to compute the autocorrelation coefficients of the phase difference. A frequency difference correcting portion obtains an average period of a periodic waveform appearing in a waveform of the autocorrelation coefficient obtained by the correlation computing portion and controls frequency of the regenerated carrier signal based on the average period so as to zero the frequency difference between the reception signal and the regenerated carrier signal. As a result, upon transmitting a modulated signal having different numbers of constellation points by time division system and receiving the signal, even when the C/N ratio is low, the carrier synchronization is carried out using information of the phase and frequency obtained periodically, so that the carrier signal is regenerated stably in a wide capture range.
Another feature of the invention is a carrier recovery circuit for regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, the circuit comprising: a region determining portion for detecting a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal, and determining which region of a phase plane each signal point is included in based on the phase difference; and a frequency difference/phase difference correcting portion for counting a determination result of the region determining portion for each phase and for each determination region rotated at a rotation speed corresponding to a set frequency, and controlling frequency and phase of the regenerated carrier signal based on the count result so as to zero a frequency difference and the phase difference between the reception signal and the regenerated carrier signal.
In the last described carrier recovery circuit for regenerating a carrier signal from an I baseband signal and a Q baseband signal obtained by quadrature-demodulating a reception signal, a region determining portion detects a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal and determine which region of a phase plane each signal point is included in based on the phase difference and a frequency difference correcting portion counts a determination result of the region determining portion for each phase and for each determination region rotated at a rotation speed corresponding to a set frequency and controls frequency and phase of the regenerated carrier signal based on the count result so as to zero the frequency difference and phase difference between the reception signal and regenerated carrier signal. As a result, upon transmitting a modulated signal having different numbers of constellation points by time division system and receiving the signal, even when the C/N ratio is low, the carrier synchronization is carried out using information of the phase and frequency obtained periodically, so that the carrier signal is regenerated stably in a wide capture range.
Another feature of the invention is a receiver device for regenerating a carrier signal based on the I baseband signal and the Q baseband signal obtained by quadrature-demodulating a reception signal, and decoding the I baseband signal and the Q baseband signal so as to regenerate information, said receiver device further receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having few constellation points to be used for carrier recovery at a predetermined time interval; and establishing carrier synchronization using information about phase error and frequency error obtained in the reference signal period or in the digitally modulated signal period having constellation points.
In the last described receiver device for regenerating a carrier signal based on the I baseband signal and the Q baseband signal obtained by quadrature-demodulating a reception signal, and decoding the I baseband signal and the Q baseband signal so as to regenerate information, the receiver device further receives a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having few constellation points to be used for carrier recovery at a predetermined time interval and establishes carrier synchronization using information about phase error and frequency error obtained in the reference signal period of the digitally modulated signal or the digitally modulated signal period. As a result, upon receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having a few constellation points useful for carrier recovery at a predetermined time interval, even when the C/N ratio is low, carrier synchronization is carried out using phase and frequency error information obtained periodically and then a carrier signal is regenerated stably in a wide capture range so as to regenerate information contained in digitally modulated signal.
The receiver device for regenerating a carrier signal based on the I baseband signal and the Q baseband signal obtained by quadrature-demodulating a reception signal, and decoding the I baseband signal and the Q baseband signal so as to regenerate information, further receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having few constellation points to be used for carrier recovery at a predetermined time interval; and detecting a difference between a regeneration carrier frequency and a carrier frequency of the reception signal obtained in a reference signal period or in a digitally modulated signal period having few constellation points so as to achieve at least one of AFC function or false lock preventing function based on the detection result.
In the receiver device for regenerating a carrier signal based on the I baseband signal and the Q baseband signal obtained by quadrature-demodulating a reception signal, and decoding the I baseband signal and the Q baseband signal so as to regenerate information, the receiver device further receives a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having few constellation points to be used for carrier recovery at a predetermined time interval and detecting a difference between the regenerated carrier frequency and the carrier frequency of the reception signal obtained in a reference signal period of the digitally modulated signal or a digitally modulated signal period so as to achieve at least one of AFC function or false lock preventing function based on the detection result. As a result, upon receiving a digitally modulated signal provided with a reference signal period or with a digitally modulated signal period having a few constellation points useful for carrier recovery at a predetermined time interval, even when the C/N ratio is low, carrier synchronization is carried out using phase and frequency error information obtained periodically and then a carrier signal is regenerated stably in a wide capture range so as to regenerate information contained in digitally modulated signal.
The receiver device last described includes a regeneration carrier frequency controlled according to detuning frequency information obtained by time differential value or a primary inclination of a change of a phase obtained by observing a phase variation in a reference signal period of a reception signal or in a modulated signal period having few constellation points, under a state of frequency asynchronization.
The regeneration carrier frequency is controlled according to detuning frequency information obtained by time differential value or a primary inclination of a change of a phase obtained by observing a phase variation in a reference signal period of a reception signal or in a modulated signal period having few constellation points, under a state of frequency asynchronization. As a result, upon receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having a few constellation points useful for carrier recovery at a predetermined time interval, even when the C/N ratio is low, carrier synchronization is carried out using phase and frequency error information obtained periodically and then a carrier signal is regenerated stably in a wide capture range so as to regenerate information contained in digitally modulated signal.
In the receiver device of the present invention a detuning frequency is estimated based on periodicity of an autocorrelation coefficient waveform in a phase variation curve obtained by observing a phase variation in a reference signal period of a reception signal or in a modulated signal period having few constellation points and then a regeneration carrier frequency is controlled based on detuning frequency information obtained by the estimation operation, under a state of frequency asynchronization.
In the receiver device a detuning frequency is estimated based on periodicity of an autocorrelation coefficient waveform in a phase variation curve obtained by observing a phase variation in a reference signal period of a reception signal or a modulated signal period having few constellation points and then a regeneration carrier frequency is controlled based on detuning frequency information obtained by the estimation operation. As a result, upon receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having a few constellation points useful for carrier recovery at a predetermined time interval, even when the C/N ratio is low, carrier synchronization is carried out using phase and frequency error information obtained periodically and then a carrier signal is regenerated stably in a wide capture range so as to regenerate information contained in digitally modulated signal.
In the receiver device the regeneration carrier frequency is set at a low frequency preliminarily so as to provide a frequency of a waveform or a number of correlation peaks appearing in the autocorrelation coefficient waveform relative to a desired frequency with an offset, thereby making it possible to estimate a detuning frequency lower than the desired frequency.
Further, in the receiver device, the regeneration carrier frequency is set at a low frequency preliminarily so as to provide a frequency of a waveform or the number of correlation peaks appearing in an autocorrelation coefficient waveform relative to a desired frequency with an offset, thereby making it possible to estimate a detuning frequency lower than a desired frequency. As a result, upon receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having a few constellation points useful for carrier recovery at a predetermined time interval, even when the C/N ratio is low, carrier synchronization is carried out using phase and frequency error information obtained periodically and then a carrier signal is regenerated stably in a wide capture range so as to regenerate information contained in digitally modulated signal.
In accord with the present invention, the receiver device is a receiver device wherein whether or not carrier synchronization is established is detected based on a statistical characteristic of phase points of a signal in a modulation period having few constellation points and oscillation frequency sweep of a local oscillator for use for frequency conversion is stopped based on the detection result.
In the receiver device of the preceding paragraph whether or not carrier synchronization is established is detected based on a statistical characteristic of phase point of a signal in a modulation period having few constellation points and oscillation frequency sweep of a local oscillator for use for frequency conversion is stopped based on the detection result. As a result, upon receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having a few constellation points useful for carrier recovery at a predetermined time interval, even when the C/N ratio is low, carrier synchronization is carried out using phase and frequency error information obtained periodically and then a carrier signal is regenerated stably in a wide capture range so as to regenerate information contained in digitally modulated signal.
The receiver device of the present invention is a receiver device for regenerating a carrier signal based on the I baseband signal and the Q baseband signal obtained by quadrature-demodulating a reception signal, and decoding the I baseband signal and the Q baseband signal so as to regenerate information, said receiver device further including a carrier recovery circuit comprising: a receiving portion for receiving a digitally modulated signal provided with a reference signal period or with a digital modulation period having few constellation points to be used for carrier recovery at a predetermined time interval so as to obtain the reception signal; a region determining portion for detecting a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal, and determining which region of a phase plane each signal point is included in based on the phase difference; and a frequency difference/phase difference correcting portion for counting a determination result of the region determining portion for each phase and for each determination region rotated at a rotation speed corresponding to a set frequency, and controlling frequency and phase of the regenerated carrier signal based on the count result so as to zero a frequency difference and the phase difference between the reception signal and the regenerated carrier signal, whereby at least one of AFC function or false lock preventing function being achieved.
In the receiver device for regenerating a carrier signal based on the I baseband signal and the Q baseband signal obtained by quadrature-demodulating a reception signal, and decoding the I baseband signal and the Q baseband signal so as to regenerate information, the receiver device further includes a carrier recovery circuit comprising a receiving portion for receiving a digitally modulated signal provided with a reference signal period or with a digital modulation period having few constellation points to be used for carrier recovery at a predetermined time interval, a region determining portion for detecting a phase difference between the regenerated carrier signal and the reception signal from the I axis side signal and the Q axis side signal obtained by quadrature-demodulating the reception signal by the regenerated carrier signal and determining which region of a phase plane each signal point is included in based on the phase difference, a frequency difference/phase difference correcting portion for counting a determination result of the region determining portion for each phase and for each determination region rotated at a rotation speed corresponding to a set frequency, and controlling frequency and phase of the regeneration carrier signal based on the count result so as to zero the frequency difference and phase difference between the reception signal and regenerated carrier signal, whereby at least one of AFC function or false lock preventing function being achieved. As a result, upon receiving a digitally modulated signal provided with a reference signal period or a digitally modulated signal period having a few constellation points useful for carrier recovery at a predetermined time interval, even when the C/N ratio is low, carrier synchronization is carried out using phase and frequency error information obtained periodically and then a carrier signal is regenerated stably in a wide capture range so as to regenerate information contained in digitally modulated signal.

AFC circuit, carrier recovery circuit and receiver device capable of regenerating a carrier reliably even at the time of low C/N ratio

c/o NHK Hosogijutsukenkyusyo, 10-11, Kinuta 1-chome


A liquid ejecting apparatus includes a liquid ejecting unit that ejects ink onto paper, a first removal portion that removes adhering objects that have adhered to the paper by making contact with a first surface of the paper during transport of the paper, and a second removal portion that removes adhering objects that have adhered to the paper by making contact with a second surface of the paper during transport of the paper. The first removal portion and the second removal portion are disposed so as to partially overlap in the transport direction of the paper and so that ends of the first removal portion and the second removal portion on an upstream side in the transport direction are distanced from each other in the transport direction.

1. Technical Field
The present invention relates to liquid ejecting apparatuses that eject a liquid onto a medium such as paper.
2. Related Art
An ink jet printer that prints by ejecting ink onto paper (called simply a "printer" hereinafter) has been known as an example of a liquid ejecting apparatus that ejects a liquid onto a medium.
With this type of printer, when adhering objects such as paper particles adhere to the paper, nozzles that eject the liquid can be clogged by the adhering objects, leading to a drop in the print quality. Accordingly, a pair of brush-shaped removal members has been provided so as to make contact with both sides of paper in order to remove such adhering objects from the paper. However, when such a removal member is disposed in a transport path of the paper, a leading end of the paper can become caught on the removal member and the transport may stop, leading to a paper jam.
Accordingly, there are printers that normally evacuate one of the removal members from the transport path and move the evacuated removal member to a position where the removal member can make contact with the paper after the leading end of the paper has passed in order to suppress the occurrence of paper jams (for example, JP-A-3-61982).
Incidentally, it is necessary to provide a movement mechanism for moving the removal member in order to evacuate the removal member from the transport path, which complicates the device configuration. Meanwhile, paper particles that adhere to the paper are produced when the paper is cut to a predetermined size, and thus the paper particles often adhere to the end areas of the paper. Accordingly, it is preferable to bring the removal member into contact with, and remove the paper particles from, the leading end of the paper.
Note that this problem is not limited to printers that eject ink onto paper, and is generally present in liquid ejecting apparatuses that eject liquids onto media.


In an embodiment, a system includes: a gas distributor assembly configured to dispense gas into a chamber; and a chuck assembly configured to secure a wafer within the chamber, wherein at least one of the gas distributor assembly and the chuck assembly includes: a first portion comprising a convex protrusion, and a second portion comprising a concave opening, wherein the convex protrusion is configured to engage the concave opening.

With advances of electronic products, semiconductor technology has been widely applied in manufacturing memories, central processing units (CPUs), liquid crystal displays (LCDs), light emission diodes (LEDs), laser diodes and other devices or chip sets. In order to achieve high-integration and high-speed requirements, dimensions of semiconductor integrated circuits have been reduced and various materials and techniques have been proposed to achieve these requirements and overcome obstacles during manufacturing. Controlling the conditions of processing wafers within chambers is an important part of semiconductor fabrication technology.
Chamber components are typically assembled using screws. However, the chamber components assembled using screws may incur damage during locking and loosening of the screws. Also, the screws themselves may become damaged due to use and may corrode over time. Therefore, conventional techniques for chamber component assembly are not entirely satisfactory.

Screwless semiconductor processing chambers

Taiwan Semiconductor Manufacturing Co., Ltd.


A leakage current measurement circuit measuring a substrate leakage current and a gate leakage current in response to a variation in the size of an MOS transistor and a leakage current comparison circuit judging which one of the substrate leakage current and the gate leakage current is dominant. The leakage current measurement circuit includes a charge supply, a leakage current generator and a detection signal generator. The leakage current comparison circuit includes a charge supply, a leakage current comparator and a detection signal generator.

1. Technical Field
The present disclosure relates to a semiconductor circuit, and more particularly, to a leakage current detection circuit that detects a substrate leakage current and a gate leakage current of a CMOS transistor.
2. Discussion of the Related Art
When an MOS transistor is turned off, there is no channel formed in the MOS transistor so that current cannot flow between the drain and source regions of the MOS transistor. When a voltage lower than the threshold voltage of the MOS transistor is applied to the gate of the MOS transistor, the energy level of the conduction band of the channel region, which is determined by the voltage applied to the gate, becomes higher than the energy level of the conduction band of the drain and source regions. Charges in the source and drain regions having relatively low energy levels cannot pass through the channel region having a relatively high energy level and disposed between the source and drain regions. Thus, the current cannot flow in the channel region.
When the MOS transistor is turned on, the charges in the source and drain s regions are moved through the channel that is formed in the direction of the length L of the gate. When a voltage that is higher than the threshold voltage is applied to the gate, the energy level of the conduction band of the channel region becomes lower than the energy level present when the MOS is turned off. Thus, the charges in the source and drain regions can easily move.
With the development of improved semiconductor manufacturing techniques, the sizes of integrated elements are scaled down in order to increase the number of integrated transistors. An MOS transistor is scaled down so that the absolute length L and absolute width W of the gate of the MOS transistor are reduced, but the ratio W/L of the length L to the width W of the gate of the MOS transistor is maintained.
When the absolute length L of the gate of the MOS transistor is reduced due to scaling down the MOS transistor, a leakage current between the drain and source of the MOS transistor is easily generated, even when the MOS transistor is turned off. As described above, a voltage lower than the threshold voltage, when applied to the gate of the MOS transistor, increases the energy level of the conduction band of the channel region when the MOS transistor is turned off. However, the width of the conduction band corresponding to the reduced length L of the channel is decreased, and thus charges penetrating the conduction band are generated to cause a leakage current. Here, this leakage current is defined as a substrate leakage current.
The MOS transistor is scaled down in consideration of reducing the voltage applied to the gate of the MOS transistor. Thus, scaling down of the MOS transistor can increase the number of integrated MOS transistors and reduce power consumption of a circuit composed of the MOS transistors. To reduce the voltage applied to the gate, the thickness of a gate insulating layer should be decreased. When the gate insulating layer is thick, charges disposed on both sides of the gate insulating layer cannot move through the gate insulating layer unless they get an enormous amount of energy. When the gate insulating layer becomes thin, however, there exist charges penetrating the gate insulating layer to generate a leakage current. This leakage current is called the gate leakage current.
The ratio W/L of the length L to the width W of the gate is an important factor in determining the current-voltage characteristic of the corresponding MOS transistor. When the length L of the gate is long and the width W is wide, the substrate leakage current does not have a large effect on the current-voltage characteristic of the MOS transistor. Particularly, the gate leakage current hardly affects the current-voltage characteristic of the MOS transistor. When the MOS transistor is scaled down, however, the effect of the gate leakage current, as well as the effect of the substrate leakage current on the current-voltage characteristic of the MOS transistor, cannot be ignored.
Conventionally, a variation in the substrate leakage current and/or a variation in the gate leakage current in response to a variation in the size of the MOS transistor were detected and reflected in the circuit design and process design. In general, the variation of one of the substrate leakage current and the gate leakage current was detected.
A conventional method of measuring the substrate leakage current and gate leakage current was carried out on a specific region of a semiconductor device not just on one MOS transistor. Furthermore, there was a method of detecting only variations in the substrate leakage current in response to variations in the size of the MOS transistor to compare the detected variations in the substrate leakage current or detecting only variations in the gate leakage current in response to variations in the size of the MOS transistor to compare the detected variations in the gate leakage current. However, using this method it is difficult to judge which one of the substrate leakage current and the gate leakage current generated in the same semiconductor device has a dominant effect on the current-voltage characteristic of the MOS transistor.

Leakage current detection circuit and leakage current comparison circuit


The present invention features vanilloid receptor polypeptides and vanilloid receptor-related polypeptides, specifically the capsaicin receptor subtypes VR1 and VR2 (VRRP-1), as well as the encoding polynucleotide sequences. In related aspects the invention features expression vectors and host cells comprising such polynucleotides. In other related aspects, the invention features transgenic animals having altered capsaicin receptor expression, due to, for example, the presence of an exogenous wild-type or modified capsaicin receptor-encoding polynucleotide sequence. The present invention also relates to antibodies that bind specifically to a capsaicin receptor polypeptide, and methods for producing these polypeptides. Further, the invention provides methods for using capsaicin receptor, including methods for screening candidate agents for activity as agonists or antagonists of capsaicin receptor activity, as well as assays to determine the amount of a capsaicin receptor-activating agent in a sample. In other related aspects, the invention provides methods for the use of the capsaicin receptor for the diagnosis and treatment of human disease and painful syndromes.

Pain is initiated when the peripheral terminals of a particular group of sensory neurons, called nociceptors, are activated by noxious chemical, mechanical, or thermal stimuli. These neurons, whose cell bodies are located in various sensory ganglia, transmit information regarding tissue damage to pain processing centers in the spinal cord and brain (Fields Pain (McGraw-Hill, New York, 1987)). Nociceptors are characterized, in part, by their sensitivity to capsaicin, a natural-product of capsicum peppers that is the active ingredient of many "hot" and spicy foods. In mammals, exposure of nociceptor terminals to capsaicin leads initially to the perception of pain and the local release of neurotransmitters. With prolonged exposure, these terminals become insensitive to capsaicin, as well as to other noxious stimuli (Szolcsanyi in Capsaicin in the Study of Pain (ed. Wood) pgs. 255–272 (Academic Press, London, 1993)). This latter phenomenon of nociceptor desensitization underlies the seemingly paradoxical use of capsaicin as an analgesic agent in the treatment of painful disorders ranging from viral and diabetic neuropathies to rheumatoid arthritis (Campbell in Capsaicin and the Study of Pain (ed. Wood) pgs. 255–272 (Academic Press, London, 1993); Szallasi et al. 1996 Pain 68:195–208). While some of this-decreased sensitivity to noxious stimuli may reflect reversible changes in the nociceptor, such as depletion of inflammatory mediators, the long-term loss of responsiveness can be explained by death of the nociceptor or destruction of its peripheral terminals following capsaicin exposure (Jancso et al. 1977 Nature 270:741–743; Szolcsanyi, supra).
Responsivity to capsaicin has been used to define sensory afferent fibers that transmit signals in response to noxious stimuli (chemical, thermal, and mechanical stimuli); however the precise mechanism of action has remained unclear. Electrophysiological (Bevan et al. 1990 Trends Pharmacol. Sci 11:330–333; Oh et al. 1996 J. Neuroscience 16:1659–1667) and biochemical (Wood et al. 1988 J. Neuroscience 8:3208–3220) studies have clearly shown that capsaicin excites nociceptors by increasing plasma membrane conductance through formation or activation of nonselective cation channels. While the hydrophobic nature of capsaicin has made it difficult to rule out the possibility that its actions are mediated by direct perturbation of membrane lipids (Feigin et al. 1995 Neuroreport 6:2134–2136), it has been generally accepted that this compounds acts at a specific receptor site on or within sensory neurons due to observations that capsaicin derivatives show structure-function relationships and evoke dose-dependent responses (Szolcsanyi et al. 1975 Drug. Res. 25:1877–1881; Szolcsanyi et al. 1976 Drug Res. 26:33–37)). The development of capsazepine, a competitive capsaicin antagonist (Bevan et al. 1992 Br. J. Pharmacol. 107:544–552) and the discovery of resiniferatoxin, an ultrapotent capsaicin analogue from Euphorbia plants that mimics the cellular actions of capsaicin (deVries et al. 1989 Life Sci. 44:711–715; Szallasi et al. 1989 Neuroscience 30:515–520) further suggest that the capsaicin mediates its effects through a receptor. The nanomolar potency of resiniferatoxin has facilitated its use as a high affinity radioligand to visualize saturable, capsaicin- and capsazepine-sensitive binding sites on nociceptors (Szallasi 1994 Gen. Pharmac. 25:223–243). Because a vanilloid moiety constitutes an essential structural component of capsaicin and resiniferatoxin, the proposed site of action of these compounds has been more generally referred to as the vanilloid receptor (Szallasi 1994 supra). The action of capsaicin, resiniferatoxin, and the antagonist capsazepine have been well characterized physiologically using primary neuronal cultures (see, e.g., Szolcsanyi, "Actions of Capsaicin on Sensory Receptors," Bevan et al. "Cellular Mechanisms of the Action of Capsaicin," and James et al. "The Capsaicin Receptor," all in Capsaicin in the Study of Pain, 1993 Academic Press Limited, pgs. 1–26, 27–44, and 83–104, respectively; Bevan et al. 1990, supra).
The analgesic properties of capsaicin and capsaicinoids are of much interest for their uses in the treatment of pain and inflammation associated with a variety of disorders (see, e.g, Fusco et al. 1997 Drugs 53:909–914; Towheed et al. 1997 i. Arthritis Rheum 26:755–770; Appendino et al. 1997 Life Sci 60:681–696 (describing activities and application of resiniferatoxin); Campbell et al. "Clinical Applications of Capsaicin and Its Analogues" in Capsaicin in the Study of Pain 1993, Academic Press pgs. 255–272). Although capsaicin and capsaicin related compounds can evoke the sensation of pain, cause hyperalgesia, activate autonomic reflexes (e.g., elicit changes in blood pressure), and cause release of peptides and other putative transmitters from nerve terminals (e.g., to induce bronochoconstriction and inflammation), prolonged exposure of sensory neurons to these compounds leads to desensitization of the neurons to multiple modalities of noxious sensory stimuli without compromising normal mechanical sensitivity or motor function, and without apparent central nervous system depression. It is this final phenomena that makes capsaicins and related compounds of great interest and potential therapeutic value.
Despite the intense interest in capsaicin and related compounds and their effects upon sensory afferent, the receptor(s) through which these compounds mediate their effects have eluded isolation and molecular characterization. Thus, the development of elegant systems for screening or characterizing new capsaicin receptor-binding compounds, or for identifying endogenous, tissue-derived mediators of pain and/or inflammation, have been severely hampered. To date the only means of assessing the activity of compounds as capsaicin receptor agonists or antagonists has been to examined their effects on sensory neurons in culture or in intact animals. The present invention solves this problem.

Nucleic acid sequences encoding capsaicin receptor and capsaicin receptor-related polypeptides and uses thereof

The Regents of the University of California


A learning-based building block system is described. The learning-based building block system comprises at least two stackable blocks. The at least two stackable blocks may include: a first stackable block having a cube configuration, a second stackable building block having a sprocket configuration, a third stackable building block having a half-pipe configuration, and a fourth stackable building block having a table configuration. The configuration of each of the first, the second, the third, and the fourth stackable block is unique.

Stackable and/or interconnecting blocks are common in the toy industry. These block systems improve a child's fine motor skills. With stackable building blocks, the child can stack one or more blocks having similar or unique shapes to build limitless configurations. However, these configurations typically fall easily, as there is no direct connection between any two blocks of the system. Interconnecting blocks typically have male features that engage female features, or some other similar features, allowing the child to connect a first block to a second block. The child may interconnect any number of blocks to build a structure. However, interconnecting blocks cannot be reconfigured, rearranged, or re-oriented with respect to one another without fully disconnecting the blocks and then reconnecting the blocks in the new desired configuration. Moreover, interconnecting blocks only allow the child to connect the blocks in a quantized and finite number of ways. Additionally, stackable and interconnecting block systems fail to improve a child's gross motor skills.
Therefore, interconnecting block systems fail to easily provide reconfiguration, rearrangement, and reorientation of the blocks with respect to one another without fully disconnecting the blocks and then reconnecting the blocks in the new desired configuration. Moreover, these interconnecting block systems only allow a finite number of configurations and do not function to improve a child's gross motor skills. Thus, a need exists for an improved learning-based building block system that allows for easy reconfiguration, rearrangement, and reorientation of the blocks, while providing the child with an infinite number of building configurations.

Learning-based system comprising stackable building blocks


The present disclosure provides a dipole, wherein the dipole comprises a dipole body and a feeding line used for connecting to the dipole body, wherein the dipole body comprises an asymmetric wing feature structure. According to the present disclosure, the dipole can obviously improve ±60° cross-polarization and VSWR performance, and can greatly reduce weight and reduce assembly costs.

In the field of antenna technology, dipole, as a key part of transmitting and receiving signals, plays a key role in performance and cost of antenna. However, the dipole currently used in the prior art has the following disadvantages:
1) High cost. The cost of existing dipole assembly mainly come from: the cost of a single dipole body and feeding line, as well as the cost of soldering between the dipole and the feeding line. Existing dipole(s) uses copper bar as feeding line, and after die casting on the dipole body, it is necessary to machine step hole or the like to achieve impedance matching. This makes the manufacturing cost of the dipole very high, and the connection between the dipole body and the feeding line is realized by soldering at top side, which easily leads to the unstable soldering quality.
2) Low performance. For the existing dipole, good soldering quality is the premise of stable performance, however, the soldering process is hard to control very well. The machined step is hard to adjust impedance matching as well as need and the machined step is not very stable for different batch.
3) Heavy weight. The weight of a single dipole assembly is about 45 g. Assuming that 1.3 m side-by-side SBS antenna with 22 dipoles is adopted, the weight of dipoles accounts for 6.4% of the total weight of the antenna. The heavier the antenna is, the more stringent the requirements on its assembly will be. This makes the weight of the dipole become a disadvantage factor for reducing the cost of the antenna.
In view of the above disadvantages, the following solutions are proposed in the prior art, but the effect is not satisfactory:
1) Cost side: for surface treatment, tin-plating instead of silver-plating in order to reduce the plating cost; for the direct connection between the dipole body and the feeding line, the reflow soldering is adopted instead of the resistance soldering. The whole dipole assembly can be outsourced and the cost assessment of the dipole assembly can be negotiated with the supplier to reduce the cost of the single dipole body and the dipole assembly.
2) Performance side: use automatically soldering equipment instead of artificial soldering to provide stability of soldering quality.


A steering control apparatus is provided, including a steering wheel, steered wheels, a direction varying actuator to operate the steering control wheels, a steering reaction actuator to apply steering reaction torque to the steering wheel and steering controller. The steered wheels are mechanically disconnected from the steering wheel. The steering controller outputs control commands for controlling the direction varying actuator and the steering reaction actuator.

In recent years, there has been suggested a vehicle steering controller employing a so-called steer-by-wire (hereinafter referred to as "SBW") system in which a mechanical connection between a steering wheel and steered wheels is released and a part of a steering system comprises an electrical path. Since such a SBW system does not have a mechanical connection between the steering wheel and the steered wheels, it is necessary to perform a control process for providing a driver with a contact feeling through the steering wheel; for example, when the steering wheel is turned and the turning limit is reached. Accordingly, it has been suggested to provide the driver with a mechanical contact feeling by generating the maximum reaction force in the steering reaction actuator, when deviation between a target direction varying angle and an actual direction varying angle is greater than or equal to a predetermined value. See, for example, Japanese Unexamined Patent Application Publication No. 2002-87308.


A noise compensating touch panel includes a touch module and a signal compensating module. The touch module includes transmission electrodes and sensing electrodes. The signal compensating module has a first input, a second input and an output. The signal compensating module couples to the touch module. The transmission electrodes receive scanning voltage signals sequentially. When the scanning voltage signals sense the touching by object at crossover points of a first transmission electrode and the sensing electrodes, the sensing electrodes provide sensing signals. The sensing signals include the value of a first parasitical capacitor. The second transmission electrode senses the value of a second parasitical capacitor which the second transmission electrode isn't touched by object when the second transmission electrode receives the scanning voltage signals. Then the second transmission electrode provides compensating signals. Signal compensating module receives the sensing signals and the compensating signals separately.

1. Technical Field
The present disclosure relates to a touch panel; in particular, to a noise compensating touch panel and a touch device thereof.
2. Description of Related Art
In recent years touch panel applications have been developed rapidly, as well as being utilized commonly in, for instance, ATMs, point-of-sale (POS) terminals and household automation control and management systems. Touch panels are even being used extensively in portable electronic devices such as tablet computers and smartphones, etc. A touch panel provides an intuitive input scheme that brings the conventional input interface to a more approachable level. The demand for HMI (human-machine interface) applications has therefore shown rapid growth.
According to the physical principle deployed to detect a touch point, a touch panel can be classified as resistive or capacitive. For a resistive touch panel, voltage is generated when the resistive touch panel is touched by a finger or a stylus. A capacitive touch panel is operated according to a finger contacting the touch panel for absorbing a very small current. The capacitive touch panel can be further classified as surface capacitive or projected capacitive. The projected capacitive touch panels attract industry attention due to its multi-touch capability. If a projected capacitive touch panel is integrated with a LCD to form an in-cell multi-touch panel, or a projected capacitive touch panel is integrated with an upper/lower surface of a panel color filter to form an on-cell multi-touch panel, thinness of the original panel can also be maintained. ITO (Indium Tin Oxide) is commonly used in TFT-LCD (thin-film-transistor liquid-crystal display) for holding electric charges. By reversely operating the same principle, such ITO can also be utilized as a detector, for achieving high-density detection. However, since a thin-film transistor in a TFT-LCD causes significant noise, the accuracy of capacitive sensing is especially important under the effect of such noise.

Noise compensating touch panel and touch device thereof


For each of a plurality of different tenants configured to concurrently execute in a virtual environment, a respective class loader graph can be constructed. For each respective class loader graph, unique types of edges between nodes that affect class loading can be identified. The edges can be traversed. Based on traversing the edges of the class loader graph, a respective unique dependency identifier (UDI) can be assigned to each class loader request. Class loader requests that are assigned the same UDI can be identified in at least two of the tenants. Responsive to identifying the class loader requests that are assigned the same UDI, a shared class loader can be assigned to each of the class loader requests. Each respective class loader request that is assigned the same UDI can be configured to call the shared class loader to load at least one class required by the respective tenant.

The present invention relates to the execution of workloads in a virtualized computing environment.
Heavily virtualized computing environments, for example cloud computing environments, are designed to realize cost savings by maximizing the number of workloads (e.g., programs) that are run per unit of hardware. This improves utilization rates of the hardware and energy efficiency by reducing, if not eliminating, idle time on hardware resources. Moreover, the total number of hardware resources deployed to handle the workloads is less than the number which would otherwise be deployed without the use of virtualization.
Workloads often times are written in Java™. Java™ is a general-purpose object-oriented computer programming language specifically designed to have as few implementation dependencies as possible. This allows application developers to write applications that can be run on any Java Virtual Machine (JVM), regardless of the computer architecture on which the applications are run. In this regard, a JVM provides an abstraction layer between the actual hardware and Java™ applications, imitating dedicated hardware. More particularly, a JVM interprets compiled Java™ binary code, called bytecode, for a computer's processor so that the processor can execute the bytecode, even though the bytecode is not specifically configured for the hardware on which it is executed. Thus, Java™ applications are portable, meaning that they can be executed on any type of computer architecture on which a JVM is executing.

This patent is subject to a terminal disclaimer.

Sharing of classes for modular programs in a multi-tenant environment

INTERNATIONAL BUSINESS MACHINES CORPORATION


A method for operating an electrically actuable feed pump in a hydraulic circuit, which draws in fluid from a fluid sump with a normal supplying of fluid. The fluid circulated in the hydraulic circuit can be returned back, and air is sucked in at least partially with an undersupply of fluid. The electric motor is integrated in a control circuit, which is provided with a control unit, which actuates the electric motor based on an actual rotational speed and a setpoint rotational speed with an actuation rotational speed. The evaluation unit compares the actual rotational speed to a reference rotational speed and in particular always with an identical current consumption. The evaluation unit then determines based on the comparison whether a fluid undersupply is present.

A generic hydraulic system of this type, which provided the starting point of the present invention, is known from DE 10 2011 100 836 A1. The electric motor of the feed pump of the hydraulic system is integrated in a control circuit which is provided with a control unit. This unit exercises controls the electric motor by setting the rotational speed on the basis of that actual rotational speed, detected by sensors, and a setpoint rotational speed. With a similar regulation of the feed pump, both the actual current consumption of the electric motor of the feed pump and the actual rotational speed of the feed pump are detected by sensors in current practice.
According to prior art it is generally not detected whether undersupplying of fluid is present in the hydraulic circuit, which can sometime lead to a transmission damage. One possible measure for detecting a fluid undersupply is arranging of a filling level sensor in the hydraulic oil sump. However, this solution is not only costly and requires many components, but in addition, the filling level sensor may be sometime also susceptible to interference during operation.

Method for operating an electrically actuable feed pump in a hydraulic circuit