A compound system and process for mapping the urethra of a male patient to detect prostate and urinary problems; evaluation of any problems found; a reinforcement insert for the prostate custom fabricated from the mapped data to alleviate any problems found; means for placing the reinforcement insert into position within the patient; and means for removing the reinforcement insert when needed; are disclosed.

The prostate is unique to the male of the species and consists of a mass of highly glandular tissue located just below the urinary bladder. The urethra exits the bottom of the bladder via a short neck which connects with the prostate. The prostate is bounded at the top by the involuntary sphincter and at the bottom by the voluntary sphincter and serves an important role in the production of seminal fluid during intercourse. The shape of the prostate has been compared to a chestnut, or a small turnip. It has a normal diameter of an inch and a half, and about an inch in length from top to bottom. The prostate consists primarily of numerous small glands that are bunched together in two large lateral lobes and a smaller middle lobe.
In cross section, the prostate normally shows a triangular arrangement with the two lateral lobes, appearing almost circular in section, lying on either side of the urethra on the side closest to the rectal wall, and a middle lobe being smaller and nestling between the lateral lobes on the front side of the prostate. The entire organ is encased in a tough muscular sheath, and is attached via a short neck to the base of the urinary bladder. The neck passes through a sheet of muscle, forming the involuntary sphincter, that underlies the fascia covering the bottom of the abdominal cavity. The bladder lies above the fascia within the abdominal cavity, and the prostate lies just below that fascia. As the urethra leaves the prostate it passes through another sheet of muscle, which forms the voluntary sphincter, and then into the penis. The retention of urine in the bladder is controlled by the two sphincters, voluntary and involuntary. The involuntary sphincter is the primary mechanism responsible for continence as it constricts the urethra and prevents the leakage of urine at volumes too low to be noticeable by the individual and during sleep. The voluntary sphincter acts as a secondary backup when there is a large quantity of urine. Urination is effected by a relaxation of both the sphincters combined with muscular contraction of the bladder and aided by gravity.
It has been estimated that, with advancing age, as many as 80% of all men will be affected by prostate problems. The primary prostate problem encountered is enlargement of the prostate, or Benign Prostatic Hyperplasia (BPH). The symptoms of BPH start with difficulty in voiding, difficulty in voiding completely, frequent urination (interruption of sleep), urinary tract infections from pooling of the urine, and can progress to over distention of the bladder, and kidney failure. In an individual suffering from BPH, excess tissue growth within the prostate applies pressure to the urethra, constricting the normal flow of urine, potentially to the point of complete blockage.
In this situation, muscular contraction of the bladder cannot overcome the constriction to force the urine through, because of the nature of the mechanical relationship of the bladder and the prostate. When the bladder contracts, it pulls down toward the base. Because it is anchored only at the base, it pulls against that anchor. The prostate is, in effect, that anchor. Normally, both sphincters relax, there is no constriction of the urethra, and the urine flows. However, when BPH is present, it acts like a sphincter which never relaxes. Therefore, the pressure generated by the bladder is also applied to the prostate (and thus to the BPH) in an additive manner. Pressure generated by the bladder and transferred to the prostate is applied equally to the BPH, so no matter how much pressure is generated by the bladder, and it can be enough to cause the bladder to bulge into pockets between the muscle bundles, it cancels out so the flow of urine is still blocked according to the degree of constriction caused by the amount of BPH present.
BPH in the majority of cases involves the middle lobe of the prostate which cannot be examined through the digital rectal approach. Diagnosis is entirely dependent on the symptoms. There is also no current technology to permit the physician to actually measure the pressure or the volume of BPH present within the prostate.
In addition to BPH, another abnormal condition that may be found within the prostate is the presence of a tumor. The symptoms of BPH are clear and obvious, and the physician can make a general diagnosis on the basis of patient response to questions. Diagnosis of the presence of a tumor, particularly in the early stages, is presently exceedingly difficult to achieve with any degree of reliability. Digital examination through the rectum is used to check the lateral lobes of the prostate for the presence of nodules. If a tumor is large enough, and in an accessible location it can be felt by the examining physician. The middle lobe of the prostate is not accessible via this approach. There is a blood test to detect the presence and amount of a substance called prostate specific antigen, (PSA) which is used to calculate the probability of the presence of cancer within the prostate. However, its use as a screening tool is controversial, and its reliability as a diagnostic tool is not high.
There are Endo-Rectal Ultrasound devices available at this time that can be pressed against the area of the rectum closest to the prostate to provide a means of scanning the prostate to look for signs of cancer. This method also is controversial owing to the difficulty in interpretation of the data. Either digital or endo-rectal ultrasound can be used to guide a biopsy needle to the suspected location. This is a difficult procedure however, as it is done without being able to see where the needle is to be inserted.
During patient evaluation for suspected prostate problems, a cystoscope is usually passed through the urethra into the bladder to assess the general condition of the uro-genital tract. Current cystoscopes are limited to purely visual inspection and add nothing to the physicians' arsenal of tools for the detection of cancer in the absence of an obvious lesion of the urethral wall or a visible mass in the bladder. If a tumor is suspected in any examination a biopsy is made through the rectal wall. None of these procedures have a good track record for accurate diagnosis of the presence of prostate cancer, particularly in the early stages.
If the diagnosis is BPH, there are a limited number of treatments available. In some cases of mild BPH, drug treatment and/or dietary modification may temporarily alleviate the symptoms. Also, there is a treatment for BPH, similar to balloon angioplasty, where the tissue is over-distended mechanically. This, too, is a temporary solution. The best and most common treatment is surgical intervention, generally, the TransUrethral Resection (TUR). In this method, a modified cystoscope, fitted with electrical or mechanical cutters, is introduced into the prostate via the urethra. This device is used to cut away the BPH tissue from the inside of the prostate.
If cancer were to be discovered at an early enough stage, a TUR could be employed to excise that as well. If the tumor is not detected at an early enough stage, treatment will involve the complete removal of the prostate, the lymph nodes of the groin, and possibly, the testicles. The simplest of these procedures involves an operation lasting up to an hour and a half, probably radiation treatment, and secondary complications. The most common secondary complication is the loss of fertility due to retrograde ejaculation. Also, radiation therapy, or mechanical trauma to the muscles can render the sphincters ineffective, thus making the patient incontinent.
The mechanism of retrograde ejaculation is as follows: The urethra, tightly constricted where it passes through the involuntary sphincter, after leaving the bladder opens up with the prostate into roughly a spindle shape. This shape is distorted in the upper region of the prostate by the presence of a longitudinal ridge, called the verumontanum, on one side of the urethra, which makes the urethral opening a "V" shape. This structure is thought to have the function of closing off the pathway to the bladder during ejaculation, thereby forcing the seminal fluid to exit via the penis. The ejaculatory ducts, which bring the sperm into the prostate, empty into the lower portion of the urethra below this area. The glandular tissue that makes up the prostate secretes the necessary seminal fluid to make up the rest of the ejaculate.
A TUR procedure normally destroys the verumontanum structure, permitting the retrograde flow of semen into the bladder. There is little or no semen ejaculated during orgasm, rendering the patient infertile. Although the sensation is said to be the same, the lack of ejaculate may have an adverse psychological effect on some individuals.
In summation; prostate problems are widespread in the older male population. The most common problem is enlarged prostate due to the presence of Benign Prostatic Hyperplasia tissue growth in the middle lobe of the prostate. Prostate cancer is also widespread and much more difficult to diagnose. At present, the best choice for treatment of either BPH or prostate cancer is, which type of surgery will be employed? Dilation and/or drug therapy may be able to temporarily relieve the symptoms but cannot correct the situation. The most popular surgery (TUR) is expensive, with an extended recovery time, no guarantee of permanence, it generally renders the patient infertile, and sometimes incontinent.
There is thus a definite need in the art for an alternate, more effective procedure for detecting, evaluating, and treating BPH and cancer of the prostate. Patents have been granted for "stents" that can be implanted in the prostate to hold open the lumen of the urethra without the necessity for surgery. However, these patented devices serve more in the nature of a stop-gap measure than an effective treatment. None of the patented stents are practically removable should the need arise. None of the patented stents offer any accommodation for variations between individuals. None of the patented "stents" has attempted to take a comprehensive approach to the problem. None of the current approaches enhances the physician's ability to detect, diagnose or quantify the status and progression, or treat abnormalities found in the prostate of a patient.
Accordingly, it is an object of the present invention to provide an accurate, cost effective, system and process for detecting, diagnosing, quantifying the status and progression, as well as treating of any abnormalities found in the prostate of a patient.
It is a further object of the present invention to provide a system for detecting, evaluating and treatment of Benign Prostatic Hyperplasia (BPH) in the prostate of a patient.
A further object of the present invention is a system that serves to provide a dimensional profile of the prostate to permit custom fabrication of a reinforcement insert for a specific patient.
A further object of the present invention is a system that measures the radial pressure within the prostatic urethra and provides the measured pressure in tabular form, relative to the dimensional profile of the prostate, to permit custom design of an implantable reinforcement insert for that individual.
A further object of the present invention is to provide a biocompatible reinforcement insert, custom fitted to the individual, that will maintain the lumen of the prostate open without the necessity for surgical removal of BPH tissue.
A further object of the present invention is an instrument for laying in place a custom made reinforcement insert within the prostatic urethra of an individual and for removal of that reinforcement insert when desired.
Still another object of the present invention is to provide a custom designed reinforcement insert for the prostatic urethra that includes a one way valve, permitting flow of fluid out of the bladder but not back into the bladder.
Still another object of the present invention is to provide a custom designed reinforcement insert for the prostatic urethra that includes a rotary valve that can serve to restore continence to individual patients wherein damage to the sphincter muscles has rendered that patient incontinent.
A further object of the present invention is a system that provides the capability of ultrasonically mapping from within the prostatic urethra the location and volume of any abnormality that may be present.
A further object of the present invention is a system that provides the capability of ultrasonically mapping from within the prostatic urethra, the tissue volume of the prostate at frequencies high enough (up to 50 MHz) to give sufficient resolution to permit diagnosis of malignancy of detected tumors.
Still another object of the present invention is an apparatus and process for providing radioactive treatment to the immediate area of a prostatic cancer, and the removal thereof at expiration of the desired application time.

System and process for the detection, evaluation and treatment of prostate and urinary problems


An implantable, time-released substance delivery device includes a casing having an exterior surface, and a number of pores disposed on the exterior surface of the casing. The time-released substance delivery device further has an interior chamber disposed within the casing, and a number of excretion tubes disposed within the casing. Each of the excretion tubes fluidly connects the interior chamber to one of the pores.

1. Field of the Invention
The present invention relates generally to medical implants and, more particularly, to medical implants for providing a time-released delivery of drugs.
2. Description of Related Art
A medicinal substance can be administered to a patient systemically or locally. A systemically administered medicinal substance enters into the blood stream, travels throughout the body, and, hopefully, reaches the part of the patient's body in need of treatment at an effective dose before being degraded by metabolism and excreted. The systemic administration of medicinal substances can be achieved by oral application (e.g., syrups, tablets, capsules and the like), needle injection, transdermal delivery (e.g., a medicinal substance incorporated into a skin patch), and subdermal delivery (e.g., a medicinal substance formulation in a matabolizable matrix placed beneath the skin to release, for example, nicotine or birth control drugs). Systemically delivered medicinal substances can be inefficient, when only a small amount of the administered dose reaches its site of therapeutic action. Moreover, with systemic delivery a medicinal substance can enter parts of the body where it can actually do harm or produce a noxious side effect.
Medicinal substances can be delivered locally by injection (e.g., injection of anesthetic into a patient's gums) or topically (e.g., creams, ointments, and sprays). Although the local delivery of medicinal substances can in some instances overcome the problems of dilution and migration, local medicinal substance delivery can be difficult in certain cases, leaving systemic administration as the viable alternative. Even when local delivery of medicinal substances to a target site is possible, an important consideration still remains of maximizing the therapeutic effectiveness of the local drug delivery by controlling the proper dose and duration of the local delivery of the medicinal substance.


A method is provided for supplying a customized data converter fabricated from a universal function die. The method initially fabricates a plurality of universal data converter dice. Each universal data converter die is capable of performing a first plurality of data conversion algorithms. After the dice are made, each universal data converter die is tested to verify the performance of the first plurality of data conversion algorithms. Subsequently, a request is received for a customized data converter capable of performing a first data conversion function, which is selected from among the first plurality of data conversion algorithms. The method then fabricates a customized data converter capable of performing the first data conversion function, using a tested universal data converter die. The unselected data converter functions are disabled (not enabled). A configuration interface may be used to enable the requested data conversion function.

1. Field of the Invention
This invention generally relates to analog-to digital and digital-to-analog data conversion and, more particularly, to a system and method for customizing a universal data conversion device, capable of potentially performing many different types of functions.
2. Description of the Related Art
As noted in Wikipedia, an ADC is a device that converts a continuous physical quantity, such as voltage, to a digital number that represents the analog quantity's amplitude. The conversion involves quantization of the input, so it necessarily introduces a small amount of error. Instead of doing a single conversion, an ADC often performs the conversions by sampling the input periodically. The result is a sequence of digital values that have converted a continuous-time and continuous-amplitude analog signal to a discrete-time and discrete-amplitude digital signal.
An ADC is often characterized by its input bandwidth, the range of input signal frequencies it can measure, and its signal-to-noise ratio (SNR). SNR is the accuracy with which a signal can be measured with respect to the noise it introduces. The SNR of an ADC is influenced by many factors, including the resolution, which is the number of output levels to which it can quantize a signal. Linearity and accuracy, or how well the quantization levels match the true analog signal, and aperture jitter, small timing errors that introduce additional errors, also influence the SNR. The SNR of an ADC is often summarized in terms of its effective number of bits (ENOB), the number of bits of each measure it returns that are on average not noise. ADCs are chosen to match the bandwidth and required SNR of the signal to be quantized.
Conventionally, if an ADC operates at a sampling rate greater than twice the bandwidth of the signal, then perfect reconstruction is possible given an ideal ADC and neglecting quantization error. The presence of quantization error limits the SNR of even an ideal ADC. However, if the SNR of the ADC exceeds that of the input signal, its effects may be neglected resulting in an essentially perfect digital representation of the input signal.
The resolution of the converter indicates the number of discrete values it can produce over the range of analog values. The resolution determines the magnitude of the quantization error and therefore determines the maximum possible average SNR for an ideal ADC without the use of oversampling. The values are usually stored electronically in binary form, so the resolution is usually expressed in bits. In consequence, the number of discrete values available, or "levels", is assumed to be a power of two. For example, an ADC with a resolution of 8 bits can encode an analog input to one in 256 different analog levels, since 28=256. Resolution can also be defined electrically, and expressed in volts. The minimum change in voltage required to guarantee a change in the output code level digital signal is called the least significant bit (LSB) voltage.
The analog signal is continuous in time and it is necessary to convert this to a flow of digital values. Therefore, a rate must be determined at which new digital values are sampled from the analog signal. The rate of new values is called the sampling rate or sampling frequency of the converter. A continuously varying bandlimited signal can be sampled as the signal values at intervals of time T, the sampling time, are measured and stored. Then, the original signal can be exactly reproduced from the discrete-time values by an interpolation formula. The accuracy is limited by quantization error. However, this faithful reproduction is typically only possible if the sampling rate is higher than twice the highest frequency of the signal. This is essentially what is embodied in the Shannon-Nyquist sampling theorem.
An ADC works by sampling the value of the input at discrete intervals in time. Provided that the input is sampled above the Nyquist rate, defined as twice the highest frequency of interest, then all frequencies in the signal can be reconstructed. If frequencies above half the Nyquist rate are sampled, they are incorrectly detected as lower frequencies, a process referred to as aliasing. Aliasing occurs because instantaneously sampling a function at two or fewer times per cycle results in missed cycles, incorrectly giving the appearance of a lower frequency. To avoid aliasing, the input to an ADC may be low-pass filtered to remove frequencies above half the sampling rate. This filter is called an anti-aliasing filter.
Although aliasing in most systems is unwanted, in some aspects it may be exploited to provide simultaneous down-mixing of a band-limited high frequency signal. The alias is effectively the lower heterodyne of the signal frequency and sampling frequency.
Signals are often sampled at the minimum rate required, for economy, with the result that the quantization noise introduced is white noise spread over the whole pass band of the converter. If a signal is sampled at a rate much higher than the Nyquist frequency, and then digitally filtered to limit it to the signal bandwidth, there are many advantages. A digital filter can have better properties, such as a sharper rolloff, than an analog filter, so a sharper anti-aliasing filter can be realized. Subsequent to filtering, the signal can be downsampled. This technique creates an effectively larger resolution than can be provided by an ADC device acting alone.
These are many ways of implementing an electronic ADC. A direct-conversion ADC or flash ADC has a bank of comparators sampling the input signal in parallel, each firing for their decoded voltage range. The comparator bank feeds a logic circuit that generates a code for each voltage range. Direct conversion is very fast, capable of gigahertz sampling rates, but usually has only 8 bits of resolution or fewer, since the number of comparators needed, 2N−1, doubles with each additional bit, requiring a large, expensive circuit. ADCs of this type typically have a large die size, a high input capacitance, high power dissipation, and are prone to produce glitches at the output (by outputting an out-of-sequence code). U.S. Pat. No. 8,519,876, invented by Zhi-Ming Lin, filed on Mar. 27, 2012, is incorporated herein by reference, and provides an example of a flash ADC.
A successive-approximation ADC uses a comparator to successively narrow a range that contains the input voltage. At each successive step, the converter compares the input voltage to the output of an internal digital to analog converter which might represent the midpoint of a selected voltage range. At each step in this process, the approximation is stored in a successive approximation register (SAR). U.S. Pat. No. 8,542,144, invented by A. Coban, filed on Sep. 30, 2011, is incorporated herein by reference, and provides an example of a successive-approximation ADC.
A ramp-compare ADC produces a saw-tooth signal that ramps up or down then quickly returns to zero. When the ramp starts, a timer starts counting. When the ramp voltage matches the input, a comparator fires, and the timer's value is recorded. Timed ramp converters require the least number of transistors. The ramp time is sensitive to temperature because it is dependent upon the circuit generating the ramp.
The Wilkinson ADC is based on the comparison of an input voltage with that produced by a charging capacitor. The capacitor is allowed to charge until its voltage is equal to the amplitude of the input pulse. A comparator determines when this condition has been reached. Then, the capacitor is allowed to discharge linearly, which produces a ramp voltage. At the point when the capacitor begins to discharge, a gate pulse is initiated. The gate pulse remains on until the capacitor is completely discharged. Thus, the duration of the gate pulse is directly proportional to the amplitude of the input pulse. This gate pulse operates a linear gate which receives pulses from a high-frequency oscillator clock. While the gate is open, a discrete number of clock pulses pass through the linear gate and are counted by the address register. The time the linear gate is open is proportional to the amplitude of the input pulse, thus the number of clock pulses recorded in the address register is proportional to the amplitude. Alternatively, the charging of the capacitor can be monitored, rather than the discharge.
An integrating ADC, also known as a dual-slope or multi-slope ADC, applies an unknown input voltage to the input of an integrator and allows the voltage to ramp for a fixed time period (the run-up period). Then a known reference voltage of opposite polarity is applied to the integrator, and is allowed to ramp until the integrator output returns to zero (the run-down period). The input voltage is computed as a function of the reference voltage, the constant run-up time period, and the measured run-down time period. The run-down time measurement is usually made in units of the converter's clock, so longer integration times allow for higher resolutions. The speed of the converter can be improved by sacrificing resolution.
A delta-encoded (tracking) ADC or counter-ramp has an up-down counter that feeds a digital-to-analog converter (DAC). The input signal and the DAC both go to a comparator. The comparator controls the counter. The circuit uses negative feedback from the comparator to adjust the counter until the DAC's output is close enough to the input signal. The number is read from the counter. Delta converters have very wide ranges and high resolution, but the conversion time is dependent on the input signal level. Some converters combine the delta and successive approximation approaches; this works especially well when high frequencies are small in magnitude. U.S. Pat. No. 8,358,231, invented by Killat et al., with a priority date of Feb. 21, 2011, which is incorporated herein by reference, provides an example of a delta-encoded ADC.
As noted in U.S. Pat. No. 8,368,571, invented by Eric Siragusa, filed on Mar. 31, 2011, and incorporated herein by reference, a pipelined ADC 20 converts the overall analog input AIN delivered to the first stage 24 by successively approximating in turn the analog input AI at each stage 24, to the predetermined bit width of that stage 24, then generating and amplifying the analog residue AR representing the unconverted remainder of the analog input AI at that stage 24, and passing the amplified residue MR to the next stage 24 and repeating the process. Ultimately, the ADC 20 can convert the original analog input AIN by combining the digital output DO produced by each of the individual stages 24, which can be performed by a delay and combine circuit 44, to successively build corresponding digitized residues DR into the overall digital output DOUT. Other architectures are known in the art that can be configured to improve resolution.
An oversampling ADC, oversamples an analog input signal by a large factor and filters the desired signal band. In a sigma-delta version of this ADC, the resulting signal, along with the error generated by the discrete levels of a flash ADC, is fed back and subtracted from the input to the aliasing filter. This negative feedback has the effect of noise shaping the error due to the flash, so that it does not appear in the desired signal frequencies. A digital filter (decimation filter) follows the ADC that reduces the sampling rate, filters off unwanted noise, and increases the resolution of the output. The use of "noise-shaping" through analog feedback mechanisms is not required to benefit from oversampling, but noise shaping makes oversampling more efficient (more resolution with less oversampling). However, this process requires approximately greater than 16× oversampling to be effective, as well as analog filter and feedback mechanisms. Simple decimation filtering of a flat (white) noise data converter yields an effective 3 dB SNR for every octave of oversampling. US 2010/0283649, invented by Bos et al., with a priority date of May 7, 2010, is incorporated herein by reference, and provides an example of a sigma-delta ADC.
A time-interleaved ADC uses M parallel ADCs where each ADC samples data every M:th cycle of the effective sample clock. The result is that the sample rate is increased M times compared to what each individual ADC can manage. Technologies exist to correct time-interleaving mismatch errors. An ADC with an intermediate frequency modulation (FM) stage first uses a voltage-to-frequency converter to convert the desired signal into an oscillating signal with a frequency proportional to the voltage of the desired signal, and then uses a frequency counter to convert that frequency into a digital count proportional to the desired signal voltage. U.S. Pat. No. 8,542,142, invented by Stein et al., filed on Feb. 21, 2013, is incorporated herein by reference, and provides an example of an interleaved ADC.
A time-stretch analog-to-digital converter (TS-ADC) digitizes a very wide bandwidth analog signal, which cannot be digitized by a conventional electronic ADC, by time-stretching the signal prior to digitization. This technique effectively slows the signal down in time and compresses its bandwidth. As a result, an electronic backend ADC that would have been too slow to capture the original signal, can now capture this slowed down signal.
Other types of ADCs, and variations of the above-mentioned ADC type include the following. U.S. Pat. No. 8,542,140, invented by Chen et al., filed on Jan. 12, 2012, is incorporated herein by reference, and provides an example of an exponential-logarithmic ADC. U.S. Pat. No. 8,471,751, invented by Zhenning Wang, filed on Jun. 30, 2011, is incorporated herein by reference, and provides an example of a time-to-digital converter (TDC).
A digital-to-analog converter (DAC) converts a digital signal, typically represented by a series of binary logic symbols, into an analog current or voltage. In a pulse-width modulator DAC type, a current or voltage is switched into a low-pass analog filter with a duration determined by the digital input code. Oversampling or interpolating DACs, such as the delta-sigma DAC, use a pulse density conversion technique. The DAC is driven with a pulse-density modulated signal, created with the use of a low-pass filter, step nonlinearity (the actual 1-bit DAC), and negative feedback loop, in a technique called delta-sigma modulation. This results in an effective high-pass filter acting on the quantization (signal processing) noise, thus steering this noise out of the low frequencies of interest into the megahertz frequencies of little interest, which is called noise shaping.
The binary-weighted DAC contains individual electrical components for each bit of the DAC connected to a summing point. These precise voltages or currents sum to the correct output value. A switched resistor DAC contains of a parallel resistor network. Individual resistors are enabled or bypassed in the network based on the digital input. A switched current source or current steering DAC uses different current sources selected by the digital input. A switched capacitor DAC contains a parallel capacitor network. Individual capacitors are connected or disconnected with switches based on the input.
A R-2R ladder DAC is a binary-weighted DAC that uses a repeating cascaded structure of resistor values R and 2R. A successive-approximation or cyclic DAC successively constructs the output during each cycle. Individual bits of the digital input are processed each cycle until the entire input is accounted for.
The thermometer-coded DAC contains an equal resistor or current-source segment for each possible value of DAC output. An 8-bit thermometer DAC would have 255 segments, and a 16-bit thermometer DAC would have 65,535 segments. To minimize the number of components, the DAC may use banks of segments, where a digital value is represented by a combination segment values. This segmented DAC combines the thermometer-coded principle for the most significant bits and the binary-weighted principle for the least significant bits. In this way, a compromise is obtained between precision (by the use of the thermometer-coded principle) and number of resistors or current sources (by the use of the binary-weighted principle).
Conventionally, in designing a product, the manufacturer of an electrical system determines the performance required by an ADC or DAC, specifying characteristics such the data rate, dynamic range, digital output signal resolution, and SNR. Upon determining the circuit performance required, the circuit is designed from discrete components, or an integrated circuit (IC) is purchased from a vendor. In the case of the IC, the printed circuit board (PCB) upon which the circuit is mounted must be designed to conform to a pre-existing IC pin out, or a custom IC designed with a pin out that conforms to the PCB.
An advancement in the manufacturing process is described in U.S. Pat. No. 8,548,071, where the IC design process begins by selecting a predetermined number of ADCs (or DACs), and assigning the ADCs to input/output ports based upon the desired data rate. Configuration data is generated for programmable interconnects between the ports and ADCs, which is then loaded into the IC (FIGS. 3, 18, and 19). Advantageously, data rate, power, and resolution design requirements can be addressed by selecting the number of parallel channels or by the use of an interleaving technique (FIGS. 4-8). In some aspect, the routing to different ADC circuits can be made to periodically change based upon clock speed (FIG. 11). While this process may simplify the design of an IC, the problem remains that once the IC is designed, its use is still limited to a particular customer and a particular implementation. This problem necessarily impacts overall product performance and options, as well as ADC component lead times and costs.
It would be advantageous if it were possible to design a data converter IC, fabricated initially to potentially perform a wide variety of data converter functions, which could be simply modified during fabrication or in the field to perform the particular function desired by the user.


A functional element is coupled to a retaining element such that the functional element can be releasably coupled to a pole, and more preferably a pole of a furniture item. Even more preferably, the functional element is a shelf, an audio, and/or a display device, and the retaining element comprises a pair of brackets to which the functional element is coupled. Most preferably, the furniture item is a floor lamp having a tubular lamp stand to which the retaining element is coupled.

Various pole-mounted devices are known in the art, and depending on the particular intended purpose, various configurations have been realized. However, all or almost all of the presently known pole-mounted devices require a support structure that interferes with either function and/or esthetics of the mounted device. Still further, depending on the particular configuration, some of the known pole-mounted devices need to be threaded onto the pole, which is at least inconvenient, if not even impossible in some cases.
For example, as described in U.S. Pat. No. 5,522,514, relatively thick support sleeves retain a shelf above a table in a predetermined position. While such support is relatively simple and can typically implemented without tools, the distance between the shelf and the table is generally predetermined by the size of the support sleeve. Similar configurations are disclosed in U.S. Pat. Nos. 3,414,133 and 5,931,315. To overcome at least some of the problems associated with fixed height, a securing wedge can be slid onto a pole at any desirable position, and a corresponding compression fit element supports a shelf on the securing wedge as taught in U.S. Pat. No. 6,123,206. However, in such configurations, the wedge has to be installed from the top or bottom portion of the pole. Similar difficulties are encountered with the tray system as described in U.S. Pat. No. 6,477,966 in which a first sleeve must be installed from the top or bottom portion of the pole.
Sleeveless storage systems for column-mounting are described in U.S. Pat. No. 6,837,386 where a plurality of pie-shaped segments are affixed to the column by an adhesive strip and/or peripheral strap. Alternatively, adjustable collars have been employed to retain a shelf on a stove pipe as described in U.S. Pat. No. 535,767, and an articulated shelf that is wrap-mounted to a stove pipe was disclosed in U.S. Pat. No. 475,149. While such systems provide at least some advantages, several other disadvantages remain. Among other things, retention of the stove pipe may be less than desirable, and or excessive weight may damage the stove pipe. Also, where adhesive tape is employed, removal of the shelf tends to leave marks or tacky residue.
Therefore, while numerous configurations and methods for pole-mounted devices are known in the art, all or almost all of them suffer from one or more disadvantages. Thus, there is still a need to provide improved configurations and methods for pole-mounted devices.


A sample-and-hold amplification circuit comprises an amplifier, a first sample-and-hold unit, and a second sample-and-hold unit. The amplifier has an input terminal and an output terminal. The first sample-and-hold unit is coupled to the input terminal and the output terminal. The second sample-and-hold unit is coupled to the input terminal and the output terminal. When the first sample-and-hold unit is arranged to perform a sampling operation, the second sample-and-hold unit performs a holding operation, and when the first sample-and-hold unit is arranged to perform the holding operation, the second sample-and-hold unit performs the sampling operation.

1. Field of the Invention
The invention relates to a sample-and-hold amplification circuit, and more particularly to a sample-and-hold amplification circuit which simultaneously perform sampling and holding operations.
2. Description of the Related Art
FIG. 1 shows a conventional sample-and-hold amplification circuit. As shown in FIG. 1, a sample-and-hold amplification circuit 1 comprises an amplifier 10, pass switches A1-A6 and B1-B4, and capacitors C1-C4. The pass switches A1-A3 and B1-B2 and the capacitors C1-C2 form sample-and-hold unit 11. The pass switches A4-A6 and B3-B4 and the capacitors C3-C4 form sample-and-hold unit 12. The pass switches A1-A6 are turned on according to a sample clock signal CL11, while the pass switches B1-B4 are turned on according to a hold clock signal CL12. The sample clock signal CL11 is inverse to the hold clock signal CL12.
When the sample clock signal CL11 is active, the pass switches A1-A6 are turned on while the pass switches B1-B4 are turned off, and positive input voltage Vip and negative input voltage Vin are respectively stored into capacitors C1 and C3, such that both of the sample-and-hold units 11 and 12 perform sampling operations. When the hold clock signal CL12 is active, the pass switches A1-A6 are turned off while the pass switches B1-B4 are turned on, and the stored positive input voltage Vip and negative input voltage stored Vin are coupled into the amplifier 10, such that both of the sample-and-hold units 11 and 12 perform holding operations. The amplifier 10 thus generates output voltage signals. Each sample-and-hold unit performs the sampling or holding operation once, in other words, the sampling and holding operations are not performed simultaneously by this architecture.


A semiconductor device with a fuse is formed on a semiconductor substrate having a base semiconductor substrate and an epitaxial semiconductor layer formed thereon and defining a major surface of the semiconductor substrate. An isolation region is formed in the epitaxial semiconductor so as to completely surround and electrically isolate a selected region of the epitaxial layer on which the narrow, blowable portion of the fuse is disposed. A field oxide layer and an insulating layer are formed, in turn, over the fuse and on the main surface of the semiconductor layer and a passivation layer is formed on the insulating layer having an opening therein defined by interior sidewalls of the passivation layer which surround the selected region and which are disposed interiorally of the isolation region, and through which first opening a corresponding service of the insulating layer is exposed. A nitride layer is formed on the passivation layer, including the sidewalls thereof defining the first opening, and covering the exposed surface portion of the insulating layer, a second opening being formed in the nitride layer and exposing a surface portion of the insulating layer, the second window being smaller than the first window and not greater than the blowable portion of the fuse.

1. Field of the Invention
The present invention relates to a semiconductor device (e.g., a memory device) including fuses used, variously, for redundant circuitry or programming. For example, fuses are formed in a decoder of a static random-access memory (SRAM).
2. Description of the Related Art
A fuse of the semiconductor device is blown, as needed and using an electric current pulse or laser, for replacing a defective circuit with a redundant circuit or for programming (writing) information in a memory cell. A partial structure of the semiconductor device including a fuse has been designed to prevent an electrical short-circuit between a semiconductor substrate and a circuit including the fuse from occurring and to prevent moisture from entering into an interior of the device from the atmosphere.
Two conventional semiconductor devices with a fuse are now explained with reference to FIGS. 1A, 1B, 2A and 2B, respectively.
As shown in FIGS. 1A and lB, a portion of a first conventional semiconductor device including a fuse comprises a semiconductor substrate 1 consisting of a p-type silicon base substrate 2 and an n-type epitaxial silicon layer 3 formed thereon. In the epitaxial layer 3 a p-type isolation region 4 of a rectangular ring configuration (FIG. 1A) is formed to extend in the base substrate 2, so that a portion 3A of the epitaxial layer, below a narrow blowable portion 5A of a fuse 5, is isolated from the base substrate 2 and the other portion i.e., the portion exterior of the isolation region 4) of the epitaxial layer 3. On the substrate 1 (i.e., on the epitaxial layer 3), a field oxide layer 6 of SiO.sub.2 is formed. The fuse 5 of polycrystalline silicon, aluminum or other metal is formed on the field oxide layer 6 and has the narrow portion 5A (FIG. 1A) to be blown. An insulating layer 7 of, e.g., PSG (phosphosilicate glass) is formed over the fuse 5 and the field oxide layer 6 for isolating lower interconnections (conductive lines) including the fuse from upper interconnections. Furthermore, a passivation layer 8 of, e.g., PSG is formed on the insulating layer 7, and a nitride layer 9 of, e.g., Si.sub.3 N.sub.4 is formed on the passivation layer 8. Since the passivation PSG layer 8 is hygroscopicity (i.e., has low moisture-resistance), the nitride layer 9 having a high moisture-resistance prevents moisture from penetrating into the semiconductor device. The layers 9 and 8 are selectively etched to form an opening 10 above the narrow portion 5A.
As the occasion demands, the narrow portion 5A of the fuse 5 is irradiated with a laser beam through the opening 10, or a pulse current is fed through the fuse 5, so as to blow the fuse 5 by breaking the narrow portion 5A. The opening 10 facilitates the breaking of the narrow portion, and the insulating layer 7 prevents the broken portion from splashing (i.e., being disposed).
When fusing, the broken portion of the fuse 5 may cause damage (cracks) to the field oxide layer 6, which may to extend into the epitaxial layer 3, producing a short circuit between the fuse 5 and the epitaxial layer 3 and thereby causing trouble. The isolation region 4 is formed to prevent the short from causing trouble.
As shown in FIGS. 2A and 2B, a portion of a second conventional semiconductor device including a fuse comprises a semiconductor substrate 11 and a field oxide layer 16 of SiO.sub.2 formed on the substrate. The substrate 11 may consist of a silicon base substrate and an epitaxial layer (layer shown) formed thereon. A fuse 15 with a narrow blowable portion 15A is made of polycrystalline silicon, aluminum or other metal and is formed on the field oxide layer 16. An insulating layer of, e.g., PSG is formed over the fuse 15 and the field oxide layer 16 for isolating lower interconnections (conductive lines) including the fuse from upper interconnections. The insulating layer 17 is selectively etched to form a groove 17, surrounding the narrow portion 15A, except for two displaced, or separated, portions or gaps therein corresponding to the fuse 15. A metal guard ring 21 of, e.g., aluminum is formed to overfill the groove and come into contact with the field oxide layer 16. The guard ring 21 is separated into two portions each having a light channel shape (i.e., a cross-sectional shape of a light weight metal channel), as shown in FIG. 2A.
As mentioned above, in the first conventional device, a passivation layer 18 of, e.g., PSG is formed over the metal guard ring 21 and the insulating layer 17, and a nitride layer 19 of , e.g., Si.sub.3 N.sub.4 is formed on the passivation layer 18. The layers 19 and 18 are selectively etched to form an opening 20 above the narrow portion 15A. The fuse 15 is blown by breaking the narrow portion 15A with a laser beam or a pulse current. Of course, some of a number of the fuses are selectively blown in accordance with demands, while the majority of the fuses are not blown.
Since portions of the insulating 17 and the passivation layer 18 are exposed in the opening 20, moisture penetrates into the inside of the device through the layers 17 and 18. To prevent the moisture penetration, the metal guard ring 21 is formed so as to vertically extend through the insulating layer 17 and thereby to separate the portion of the layer 17 adjacent to and surrounding the narrow portion 15A from the rest thereof.
However, in the first conventional semiconductor device (FIGS. 1A and 1B), the moisture penetrates into the inside of the device, through the insulating layer 7 and the interface between the layers 7 and 8 from the exposed portion of the layer 7 within the opening 10. The moisture which penetrates to the inside deteriorates aluminum interconnections (lines) and active elements (e.g., transistors) of the device. Furthermore, when the cracks of the insulating layer 6 and the passivation layer 7 are caused by blowing the fuse 5, moisture may penetrate through the respective interfaces between the layers 6 and 7 and between the epitaxial layer 3 and the layer 6 from the cracks. In the second conventional semiconductor device (FIGS. 2A and 2B), when blowing the fuse 15, cracks in the layers 16 and 17 may also occur and cause trouble, such as a short circuit or moisture penetration.
The nitride layer 9 (or 19) of the first (or second) semiconductor device is formed to protect the passivation PSG layer 8 (or 18) except for the opening 10 (or 20), with the result that a side of the layer 8 (or 18) and a portion of the layer 7 (or 17) are exposed in the opening. Therefore, the nitride layer does not sufficiently contribute to improving the moisture-resistance of the semiconductor device.


A method and apparatus for developing a test for determining if an engine has oil seal leaks. The engine is charged with a predetermined pressure of air and monitored by a leak tester. A digital valve is set to provide a certain leak rate based upon signals received from a digital valve controller. Thereafter, based upon signals received from a PC and a main control unit, a variety of trials are completed. The results and programs are stored in the PC. Results of the trials allow an optimized testing program to be selected that would be best suited for use on a manufacturing assembly line.

1. Field of the Invention
The present invention generally relates to engine leak testing and more specifically, toward a method for developing a program for engine leak testing that will subsequently be used on a manufacturing assembly line.
2. Description of Related Art
During the manufacture of engines, it is desirable to test the assembled engine to determine if any of the various oil seals are leaking. Due to the construction of modern engines, it has proven difficult to develop engine leak testing methods that can be employed quickly, as is required for manufacturing efficiency. Furthermore, the testing methods are usually specific to individual engine types and thus new testing programs must be developed every time a new engine design is produced.
Development of these testing programs can be very labor intensive and requires a large amount of time. For example, when developing the testing programs, one of the set parameters, the leak rate, may range from 100 cc/min to 5000 cc/min, in increments of 25 cc/min. This results in about 200 different trials that must be run in order to properly develop a new program.
One known testing method that has been employed in the past involves having a user manually adjust and confirm the leak rate for each incremental change. Running the trials at different leak rates requires that the user change orifices to adjust the set leak rate. And, as each trial is typically run 3 to 5 times, development of a single program can require several hundred iterations. Furthermore, a wait time of typically two minutes is used between trials to ensure that any fluid pressure in the engine from the previous trial has dissipated. Accordingly, the known testing method is not an effective technique for developing a program for detecting engine oil leaks.
Therefore, there exists a need in the art for a method of efficiently developing testing programs for an engine.

Automatic control of leak test unit during testing and analysis of an engine


A support strap for holding a seal strip of a convertible top against one or more body panels of the vehicle. The seal strip has a body panel engaging portion and an attachment portion. A tensioner is operatively attached to the support strap to reduce the flexibility of the support strap and apply pressure to the seal strip to improve the effectiveness of the seal strip.

Convertible tops and retractable hardtops are moved between an extended position to cover the passenger compartment of a vehicle and a retracted position to provide an open air experience. The term "convertible top" as used in this disclosure should be construed to include soft top convertible tops and retractable hardtops. When a convertible top is extended, it is important that an effective seal is provided in every area where the top engages the vehicle body and windows. Seals are provided to exclude air and water from the passenger compartment when the top is extended.
In some areas around the periphery of the convertible top, seals may not be attached to a rail or a link that makes up part of the top stack. In particular, the sail area of the roof may be partially defined by the rear rail and five bow but gaps between these parts of the top stack leave areas where a seal is unsupported. A seal is less effective when not supported by a rigid support such as a rail and may allow leakage or wind noise in that area.
This disclosure is directed to solving the above problem and other problems as summarized below.


A method for stopping a bicycle at intersection, applied in a bicycle system including a signal light command device, a signal controller, an electromagnet emitting device, and a bicycle having a magnet adsorption device. The method includes controlling, by the signal controller, the electromagnet emitting device to generate magnetic attraction force when a stoplight of the signal light command device is turned on; and attracting, by the electromagnet emitting device, the magnet adsorption device of the bicycle to decelerate or stop the bicycle. A bicycle system and a bicycle are also provided.

Bicycles are part of urban traffic. More and more commuters are accustomed to riding bicycles, especially shared bicycles. However, traffic accidents can occur when a bicycle rider violet a stoplight. A method that can automatically stop a bicycle rider from crossing an intersection against a stoplight may reduce traffic accidents.
A method for stopping a bicycle may be achieved by installing a sensor which recognizes a red traffic light on the front of the bicycle. When the sensor recognizes a stoplight, the brake device of the bicycle is automatically activated. However, other traffic or other obstacles in front of the bicycle may obstruct the line of sight of the sensor.

Method for stopping a bicycle at a controlled intersection, bicycle system, and bicycle

Fu Tai Hua Industry (Shenzhen) Co., Ltd.


Chitosan support material is crosslinked using a heat-induced, amidification reaction in non-aqueous solvent. Crosslinking is achieved by the use of dicarboxylic acids which form amide bonds with chitosan. The type and degree of crosslinking can be controlled to tailor mechanical strength, solubility, and functionality, of the resulting chitosan support material. Quaternization and/or cyclodextrin-modification functionalization of the chitosan beads can also be effected in addition to the crosslinking to produce separation materials with great versatility and utility. The invention is applicable to chitosan support materials of various solids contents and geometrical shapes such as beads, fibers, films, and adhesive coatings.

1. Field of the Invention
The invention is generally related to a method for forming crosslinked chitosan support materials, including crosslinked and functionalized chitosan support materials, and crosslinked chitosan products obtained by this method.
2. Description of the Related Art
Hydrogel beads are products frequently prepared from polysaccharides, especially agarose, dextran and cellulose. Hydrogel beads from chitosan are also generally known.
Chitosan is the acid-soluble deacetylation product of chitin. For example, chitosan is the product of alkaline hydrolysis of abundant chitin produced in the crab shelling industry. Chitosan, a biopolymer soluble in dilute (0.1 to 10%) solutions of carboxylic acids, such as acetic acid, is readily regenerated from solution by neutralization with alkali. In this manner, chitosan has been regenerated and reshaped in the form of films, fibers, and hydrogel beads. For instance, chitosan beads are prepared in one conventional method by precipitating dilute solution of chitosan in acetic acid into alcoholic or aqueous sodium hydroxide followed by solvent exchange with water.
However, in contrast to beads from cellulose, which are insoluble in most organic solvents, acids and bases, chitosan retains the solubility in dilute acids of the parent biopolymer. This solubility is typically overcome by inducing crosslinking. A conventional chitosan crosslinking reaction involves dialdehydes, such as glutaraldehyde, or diglycidyl ethers, such as butanediol diglycidyl ether, or epoxides like epichlorohydrin. Chitosan beads crosslinked with diglycidyl ethers are commercially available under the trade name CHITOPEARL, as manufactured by Fuji Spinning, Ltd., Japan.
Also, various researchers have discussed blending chitosan and cellulose to produce biodegradable films (see, for example, U.S. Pat. No. 5,306,550 to Nishiyama et al.; Hosokawa et al., Ind. Eng. Chem. Res., 29:800-805 (1990); Hasegawa et al., J. Appl. Polym. Sci., 45:1873-1879 (1992)). Though cellulose contains only trace amounts of carbonyl groups, these trace amounts of carbonyl groups are suspected in the art to play an important role in crosslinking to chitosan to form a crosslinked polymeric network of cellulose and chitosan.
Also, it has been demonstrated that complexes of chitosan with acetic acid (viz., chitosonium acetate) are converted to chitin (i.e., the N-acetylamide of chitosan) by a heat-catalyzed amidification or dehydration reaction, in U.S. application Ser. No. 08/435,866 to Glasser et al., filed May 5, 1995. The amidification reaction described in U.S. application Ser. No. 08/435,866 converts acid-soluble chitosan into acid-insoluble chitin.
Because chitosan is easily solubilized and processed, a great deal of research in the hydrogel field has been devoted to experimentation with and/or use of chitosan in a wide variety of applications. Therefore, the art would be highly interested in a new technique to form crosslinked chitosan support material, such as crosslinked chitosan beads, in a simplified, reliable manner.

Method of making ester-crosslinked chitosan support materials and products thereof


A butane stove or heater includes a pressure vessel adapted to receive a conventional aerosol-type fuel container. The pressure vessel has a fuel conduit, connected to a pressure regulator and thence to the appliance burner unit, which is adapted for connection with a fuel container disposed therein, and a vent conduit which is adapted to vent any fuel escaping from the fuel container to a location remote from the appliance.

Small, single burner portable stoves ("cookers") using butane or butane/propane mixtures have become increasingly widely used. Such cookers use a standard disposable thinwalled "aerosol type" canister containing approximately 8 ounces of liquified fuel at a pressure that varies with ambient temperature. The canister is equipped with a springloaded pinvalve which, when depressed, permits gaseous fuel to be ejected. An orienting slot in the canister body cooperates with an aligning member on the pressure regulator to ensure that an internal canister standpipe is nominally vertical when the appliance is in use, thereby permitting only gaseous, not liquid, fuel to be ejected.
The gas canister in such a portable cooker is generally contained in an accessible, ventilated, lidded compartment within the cooker, approximately 4 inches from the burner itself. After being placed in position, the fuel canister is forcibly inserted into the pressure regulator inlet by means of a user-operated lever and associated linkage.
These cookers are typically inexpensively constructed and intended for portable use. Their general design and construction renders them extremely susceptible to misuse and abuse. Gas leakages and resulting flames frequently occur at the pressure regulator or at the canister-regulator interface.
Within the last several years, such cookers have increasingly begun to appear aboard pleasure boats, particularly aboard small powerboats wherein permanently built-in cooking appliances are often not provided. Because a small boat includes many closed spaces, such as bilges and the engine compartment, and because butane/propane mixtures are heavier than air, there is a concern that fuel leaking from the stove, fuel canister or both, will be ignited by one of the many potential ignition sources commonly found aboard such craft. The greatest hazard, however, is the abuse-to-failure of the thinwalled fuel canister itself while it is in actual use within the cooker. Such abuse is encouraged by the design of these portable cookers, such that it is very easy for an unwary user to create conditions in which the canister can and will rupture, often with serious consequences.
At the same time, it is to be noted that one type of cooking appliance, using compressed or liquified gas, has been used aboard thousands of pleasure boats for decades and has compiled an admirable safety record. In these appliances, the fuel canister is not housed within the appliance itself. Rather, the fuel canister, or canisters, is typically contained within a remotely located dedicated compartment which opens only to the outside deck, is isolated by gastight seals from all of the interior spaces of the boat, and is vented overboard so that accidental gas leakages are harmlessly discharged into open air. A supply pipe connects to the cooking appliance via a valve, inside the housing, which is controlled by a switch located near the appliance. The user thereby controls the fuel supply, shutting it off after use. Unfortunately, these installations are large, heavy, costly and thus are limited to use in larger craft.


An exercise apparatus for developing strength and flexibility of the arms, legs, back and abdominals of the user. The exercise apparatus is an adaptation of the exercise ball or Swiss ball. The exercise apparatus includes a large, spherically-shaped, resilient ball, a frame and a pair of connectors, the connectors rotatably connecting the ball to the frame. Various attachments may be placed on the frame to allow the user to grasp the apparatus or lock their feet to prevent unwanted motion. A mechanism can also be included in the connectors allowing the user to selectively adjust the rotation to a desired degree of resistance.

An exercise ball is a large, spherical, resilient ball that can be used for a variety of exercises. These balls are also commonly referred to as a "Swiss ball", "Swiss exercise ball", "stability ball" or a "pilates ball." The ball is often inflatable, made of vinyl or plastic. Alternatively, it may be made of a solid material such as foam rubber. Exercise balls were originally used for therapeutic exercises, but have been more widely adopted in recent years to develop a user's flexibility, balance and strength, including the strength of seldom used stabilizer muscles. Exercise balls are typically used on the surface of a floor, with some portion of the weight of the user coming to rest upon the ball, thereby causing a deformation of the ball as it is pressed between the user and the floor. The resultant deformation adds a limited amount of resistance to the exercise. Used in this manner, the ball adds an element of instability to the exercise. This instability would not normally be experienced by a user with the associated exercise in the absence of the ball. Efforts by the user to counteract this instability and remain balanced on the ball allow the user to more fully exercise the body. One key cause of this instability is that the ball is not secured in any manner, other than by the weight of the user. Consequently, the ball is free to travel in any two dimensional direction by means of rotation across the horizontal plane created by the underlying floor.
The inherent characteristics of exercise balls have led to the recognition of numerous therapeutic uses for them. Due in part to these uses and characteristics, exercise balls have been incorporated into a number of exercise devices and other articles. U.S. Pat. No. 5,810,700 to Orcutt discloses an exercise apparatus utilizing a resilient ball and having a flexible strap assembly surrounding the ball. The flexible strap assembly coupled to the ball provides resistance for performing exercises. The resilient ball is designed to be used by a user in a seated position atop the ball, or otherwise with the user resting a portion of his or her body on the resilient ball, while pulling the resistance member in an elongation direction. The strap assembly includes first and second straps adapted to surround and couple to the resilient ball. A loop formed from one of the straps receives the resistance member. While providing additional exercises for use with an exercise ball, this device does not address the inherent instability of exercise balls.
U.S. Pat. No. 6,309,331 B1 to Raymond discloses an abdominal exerciser device utilizing a resilient rubber ball in contact with a plurality of ball bearings across the lower half of the ball. The ball is mounted inside a semi-spherical cavity that roughly corresponds in height to the lower half of the ball. Thus, a self-standing casing is formed to support the ball while allowing the rubber ball a free-rolling action when applied against a body part such as the abdominal, waist and/or hips effectively pressuring and massaging the muscles of the body part. It is further taught that one or more casings may also be mounted on absorbing materials, which is further mounted onto a rigid frame structure adapted to support a user. U.S. Pat. No. 6,669,611 B2, also to Raymond, discloses a similar abdominal exerciser.
U.S. Pat. No. 6,746,372 B2 to Hsu discloses an exercising ball holder for fixing an exercising ball. The holder is a concave device that cups the lower portion of an exercise ball. The holder further includes a base structure having multiple extension arms and at least one elastic cord attached thereto. The base seat is formed with a rest depression. A lower end of the exercising ball is rested and located in the depression preventing the ball from easily rolling out in response to directly downward pressure. The ball is free to be lifted out of the device and may be dislodged by forces applied from a side. The multiple extension arms extend outwardly from beneath the holder and have a fixing loop section at their respective ends for affixing the elastic cords. The elastic cords have handles at the ends opposite to where they affix to the base. The elastic cords are thus adapted to function as resistance members to be grasped by the hand of a user.
Other patents disclosing chairs or exercise devices incorporating exercise ball-like objects, or variations thereof, include U.S. Pat. No. 4,126,326 to Phillips, U.S. Pat. No. 5,690,389 to Ekman et al., U.S. Pat. No. 5,833,587 to Strong et al., U.S. Pat. No. 6,461,284 B1 to Francavilla, U.S. Pat. No. 6,478,721 to Hunter and U.S. Pat. No. 6,702,726 to Lin.
As discussed above, exercise balls are useful tools for exercise, but suffer from a number of limitations as a result of their ability to roll in any direction along the horizontal plane. Exercise balls are inherently unstable. Often this instability is not desired by the user. This instability often makes it more difficult to isolate the desired muscle group or groups intended by a particular exercise motion. The feeling of instability can be unnerving to inexperienced users and may even lead to injury due to loss of balance or when otherwise used improperly. This is especially true if the user suffers from a physical ailment or handicap. Additionally, the primary source of resistance during certain exercise is the compressed nature of the weight-bearing ball. One means for adjusting the resistance is to alter the inflation of ball. Deflating the ball results in an increased resistance to rotation. Unfortunately, this results in a concomitant reduction in support to the user. As such, it is difficult to adjust the resistance to tailor it to the exercise and the user's needs. Finally, because the ball is not secured by any means, it is difficult to firmly stabilize an isolated part of the user's body, such as the user's feet or hands, so as to apply a significant amount of force to be exerted during the motion of the exercise. Thus, what is needed is an exercise apparatus that overcomes these limitations.


An integrated circuit includes at least one non-volatile memory element having first and second non-volatile transistors connected in series between first and second data lines. A junction between the first and second non-volatile transistors forms an output node. The non-volatile memory element further includes an access transistor connected between a reference voltage line and the junction between the first and second non-volatile transistors. In a programmable logic application, for example a field programmable gate array, the non-volatile memory element controls the state of a switching element, which selectively connects logic elements in the programmable logic application. Based on the voltages applied to the non-volatile memory element, the non-volatile memory element is selectively erased, programmed, operated, monitored and powered-up.

1. Field of the Invention
The present invention relates to a non-volatile memory element; and more particularly, to non-volatile memory element for programmable logic applications.
2. Description of Prior Art
A typical Field Programmable Gate Array (FPGA) includes arrays of logic elements and programmable interconnects. Each programmable interconnect serves to selectively connect logic elements. Accordingly, by programming the programmable interconnects, different logic functions are established.
Usually, a programmable interconnect in an FPGA includes a switching transistor programmed to an open or closed state by a corresponding SRAM memory cell. Based on the programmed state, the switching transistor makes or breaks an electrical connection between logic elements. Storing a logic "1" in an SRAM memory cell, for example, causes the corresponding switching transistor to conduct and electrically connect the logic elements connected to the switching transistor. Unfortunately, once configured, the SRAM memory cells require a constant power supply to maintain the programmed state.
U.S. Pat. No. 5,633,518 discloses a non-volatile programmable interconnect for FPGAs. The non-volatile programmable interconnect of this patent closely integrates the switching transistor with a non-volatile memory element for reducing the area of the FPGA, but substantially complicates the design and chip layout. In this design, the switching transistor and the memory element share a floating gate. Unfortunately, during operation, the switching transistor can inject carriers into the floating gate, and change the programmed state of the programmable interconnect.

Non-volatile memory element for programmable logic applications and operational methods therefor


Poly (organophosphazene) polymers bearing various ratios of a carboxylic acid containing sidegroup and an alkylamino, alkoxy, or alkoxy ether sidegroup are disclosed. These water-soluble macromolecules are cross-linked and allowed to absorb water to form hydrogels. Because of their anionic character and high water content, the polymeric hydrogels are useful for a wide variety of biomedical applications including controlled drug delivery (e.g. pH sensitive drug delivery), biocompatible coatings, and pH sensitive membranes.

The design and synthesis of new macromolecules for the preparation of hydrogels is one of the major challenges of modern polymer chemistry. A variety of polymeric hydrogels and their membranes are used in applications as diverse as gas separations, microfiltration, hyperfiltration, hemodialysis, electrodialysis, biocompatible coatings and controlled drug delivery. There is continuing need for new and improved hydrogels especially in biomedical engineering applications.
Hydrogels are polymeric networks which contain relatively large amounts of water. These types of materials have been investigated extensively for potential biomedical applications because of their similarities to soft tissues and their potential tissue and blood compatibility behavior. They are also of interest as membrane materials in both biological and non-biological applications and as surface coatings to generate highly hydrophilic surfaces. Of particular importance are ionic hydrogels because of their equilibrium degree of swelling is affected by changes in pH or ionic strength. These ionic hydrogels usually contain ionizable pendent groups such as carboxylic acid, sulfonic acid, or quaternized amino units. Because of their ionic nature, these hydrogels have special properties for use in membranes and in pH sensitive drug delivery systems. pH sensitive hydrogels with anionic groups, in particular, are especially promising for biomedical uses since these gels have been shown to be better bioadhesives than their cationic or neutral counterparts (see Br.o slashed.ndsted, H.; Kopecek, J. In Polyelectrolyte Gels; Harland, R. S.; Prud'homme, R. K., Ed.; ACS: Washington D. C., 1992; Vol. 480, p. 285; and Leung, S. S.; Robinson, J. R. In Polyelectrolyte Gels; Harland, R. S.; Prud'homme, R. K., Ed.; ACS: Washington D. C., 1992; Vol. 480, p. 269). Furthermore, it has been shown that anionic surfaces with high charge density generate improved blood compatibility (see Goggins, J. A. et al. In Advances in Biomedical Polymers; Gebelein, C. G., Ed.; Plenum Press: New York, 1987; Vol. 35, p. 215; and Helmus, M. N. et al. J. Biomed. Mater. Res. 1984, 18, 165).
For many biomedical applications, synthetic polymers are generally preferred over natural polymers for their reproducibility and ease of manufacture. Synthetic polymers are used increasingly in medical science due to the chemist's ability to incorporate specific properties such as strength, hydrogel characteristics, permeability or biocompatibility, particularly in fields like cell encapsulation and drug delivery where such properties are often prerequisites. However, harsh conditions, e.g., heat or organic solvents, are usually used when encapsulating with these polymers often causing difficulties in encapsulating sensitive entities, e.g. proteins, liposomes, and mammalian cells.
A number of different polymers have been used for controlled drug delivery. Some examples include the biodegradable polymers poly(anhydrides), poly(orthoesters), and poly(lactic acid) and the non-degradable polymers ethylene vinyl acetate and poly(acrylic acid). Various polyphosphazene polymers have also been shown to be useful for controlled drug delivery. For example, U.S. Pat. No. 4,880,622 to Allcock et al. and U.S. Pat. No. 5,053,451 to Allcock et al. (both incorporated herein by reference) disclose polyphosphazene polymer hydrogels including their use as drug delivery devices formed by standard techniques including: dissolution and casting of the polymer into a film or disk, dissolution of the polymer and cross-linking by covalent bonding or by irradiation to form a soft gel, and compression of polymer particles into a disk.
Synthetic polymers are also widely used for membrane applications. The synthetic polymers currently used as membranes can be divided into two categories: (1) neutral polymers such as polyethylene, poly(methyl methacrylate), poly(organosiloxanes), and cellulose acetate, and (2) ionic polymers such as poly(acrylic acid), sulfonated polystyrene, and perfluorinated ionomers. The consideration of a polymer for incorporation into membranes involves a subtle balancing of properties such as hydrophilicity, molecular weight, crystallinity, polarity, mechanical strength, and the solvation-type affinity between specific polymers and small molecule solutes or gas molecules. In these terms, the tailoring of sophisticated membrane systems is still in its infancy. For this reason, poly(organophosphazenes) are especially attractive as candidates for membrane applications.
In prior publications, we have reported that the macromolecular substitutive synthesis of poly(oranophosphazenes) allows the properties of these polymers to be varied over a wide range by the incorporation of different substituent groups (R) Allcock, H. R. Chem. Eng. News 63,22 (1985)!. These property changes can be orchestrated with great subtlety both by varying the R group in single substituent polymers and by the use of two or more cosubstituent groups attached to the same chain. In this way individual polymers may be hydrophobic, amphiphilic, or hydrophilic; water-stable or water-erodable; crystalline or amorphous; or bioinert or bioactive. Our previous work has demonstrated methods for the radiation cross-linking of specific polyphosphazenes in order to optimize their behavior as membranes or hydrogels see, for example, Allcock, H. R. et al. Biomaterials 19, 509 (1988)!.


An apparatus for monitoring the operation of a heating element moving periodically along a predefined path includes first and second sensors positioned adjacent the path of the heating element. The first sensor is configured to sense the presence of the heating element proximate to the second sensor, and the second sensor is configured to sense a temperature associated with the heating element as is passes by the second sensor. A controller receives signals from the first and second sensors and performs a control function such as indicating when the temperature sensed by the second sensor fall outside a predetermined range.

Many consumer goods are provided in sealed packages such as heat-sealed polymeric bags. When the packaged goods are perishable goods such as cereal, crackers, or other foodstuffs, it is important that the package be properly sealed to keep the goods fresh and to avoid spillage and contamination of the goods. One type of sealing device used to seal polymeric bags utilizes one or more heater blocks provided on a rotating belt. The blocks cooperate with an adjustable press plate whereby the open end of a polymeric bag positioned between the press plate and rotating belt is sealed as a heater block passes the plate. Advantageously, the speed of the belt and the spacing of the blocks on the belt can be set to correspond to the timing of filled bags provided to a sealing station including the press plate and heater blocks such that continuous sealing of bags in a production line may be accomplished.
One drawback of this type of bag sealing system is that many improperly sealed bags may pass through the sealing station without detection when one or more of the heater blocks fail. The improperly sealed bags must either be reworked or the product in the improperly sealed bags disposed of. In either case, the inability to detect failed heater blocks results in waste and increased manufacturing costs. In the worst case, the improperly sealed bags may pass through the manufacturing system undetected, ultimately resulting in unsatisfied customers.
There is thus a need for an apparatus and method for monitoring the operation of a heat sealing device so that failure of one or more of the heating elements may be detected.

System and method for monitoring heat seal devices


A beaching bow for use on watercraft, water vessels and landing craft. The beaching bow has a substantially wedge shape, and is connected to the watercraft by a flexible hinge joint near a top surface. The beaching bow includes a center of buoyancy forward to the flexible hinge joint, allowing the beaching bow to float upward and assume a proper angle depending on the floating displacement of the watercraft, and the hydrodynamic effect when the watercraft moves through the water. Upon reaching a beach or other landing surface, the beaching bow rotates down to securely interface with the beach, and allow the loading and unloading of equipment, vehicles and personnel from the watercraft.

Floating causeways have previously been designed and built which provide a downloading ramp at the forward end of the structure, which, when the structure is driven up upon the beach or shore, provide a ramp extending downwardly from the front of the vessel to the beach. Using such ramps, the off-loading of vehicles, personnel and other material is greatly facilitated. However, such structures have met with substantial problems in the past.
For example, the down ramp extending from the forward end of such floating causeways adversely impacts and limits the forward motion of the craft, especially in rough seas. Even in calm seas, the down ramp tends to pull the front end of the structure into the water, limiting the speed of the craft, causing drag, and presenting a sharp angle to the beach or shoreline when the beaching bow is landed. In rough seas, the problems are exacerbated, as the submerged beaching bow causes the waves to flow up and over the front of the structure, potentially causing further vessel control problems, as well as potentially damaging vehicles, supplies and personnel being carried by such causeways.
Other vessels, such as landing craft, have employed powered disembarking platforms which must be raised and lowered either manually or with sophisticated power devices, when the vessel is beached. When such platforms are raised, they can shift the center of gravity of the vessel, creating a top heavy vessel which is less stable. When lowered, they cause the bow to submerge, which greatly decreases speed, and increases the difficulty of making headway and maintaining direction. Again, such problems are exacerbated by rough seas, which greatly increase the drag and buffeting of any watercraft.
For example, the United States Navy employs a Navy Lightered (NL) causeway system, including a proposed Amphibious Cargo Beaching Lighter (ACBL). The ACBL uses modules which are 40 feet long, 24 feet wide, and 8 feet high. The modules are connected together using a rigid pin and guillotine connector. A ramp module is connected to the fore end. However, the ramp module is prone to the problems discussed hereinabove, including submerging, instability and poor beaching interface.
When the watercraft reaches land, inclined surfaces common to beaches makes setting up a disembarking and loading surface more difficult. For cargo, personnel and vehicles to be easily loaded and unloaded, a smooth surface without gaps or drops is required.

Beaching bow for floating platforms and watercraft


A signal (801) of a first code string made through replacing a part of a code string of a predetermined format with dummy data is sent to code string rewriting means (1802) via code string resolution means (1801). A signal (806) of a second code string for complementing the dummy data part in the signal (801) is sent to the code string rewriting means (1802) via control means (1805) and the dummy data in the first code string is rewritten to the second code string. At the time of trial viewing/listening, a signal (802) from the code string resolution means (1801) is selected by a switch (1808), and when the second code string (806) is acquired through content purchase, a signal (803) from the code string rewriting means (1802) is selected by the switch (1808). Thus, trial viewing/listening of a content such as music is made possible while the possibility of decryption is eliminated. By acquiring a relatively small quantity of data, reproduction of a high-quality content is made possible.

A content (software) distribution method is known in which, for example, an acoustic signal or the like is encrypted and then broadcast or recorded to a recording medium so that only a person who purchased a key for decryption is permitted to listen to the signal.
As an encryption method, for example, a method is known in which an initial value of a random-number sequence is given as a key signal for a bit string of a PCM acoustic signal and then a bit string obtained by taking an exclusive OR between the generated random-number sequence of 0/1 and the PCM bit string is transmitted or recorded to a recording medium. As this method is used, a person who acquired the key signal can correctly reproduce the acoustic signal and a person who did not acquire the key signal can only reproduce noise. Of course, it is also possible to use a more complicated method such as so-called DES (Data Encryption Standard) as an encryption method. Description of the DES standard is disclosed in "Federal Information Processing Standards Publication 46, Specifications for the DATA ENCRYPTION STANDARD, Jan. 15, 1977."
On the other hand, a method for compressing an acoustic signal and then broadcasting or recording the compressed acoustic signal to a recording medium is popularized, and recording media which enable recording of a coded audio signal or the like, such as a magneto-optical disc, are broadly used.
There are various techniques for high-efficiency coding of an audio signal, voice signal or the like. For example, such techniques may include subband coding (SBC), which is a non-blocked frequency band division system for dividing an audio signal or the like on the time axis into a plurality of frequency bands without blocking and then coding the band-divided audio signal, and so-called transform coding, which is a blocked frequency band division system for transforming (spectrally transforming) a signal on the time axis to a signal of the frequency axis, then dividing the signal into a plurality of frequency bands and coding the signal of each band. Moreover, a high-efficiency coding technique combining the above-described subband coding with transform coding is considered. In that case, for example, after frequency band division is carried out by the above-described subband coding, the signal of each band is spectrally transformed to a signal on the frequency axis and the spectrally transformed signal of each band is coded.
As a filter for the above-described technique, for example, a QMF filter is used. The QMF filter is described in "R. E. Crochiere, Digital coding of speech in subbands, Bell Syst. Tech. J. Vol.55, No.8, 1976". Moreover, a filter division technique with equal bandwidth is disclosed in "Joseph H. Rothweiler, Polyphase Quadrature Filters—A new subband coding technique, ICASSP 83, BOSTON".
As the above-described spectral transform, for example, the time axis is transformed to the frequency axis by blocking an input audio signal by predetermined unit time (frame) and then performing discrete Fourier transform (DFT), discrete cosine transform (DCT), modified discrete cosine transform (MDCT) or the like on each of the blocks. MDCT is described in "J.P. Princen, A. B. Bradley, Univ. of Surrey Royal Melbourne Inst. of Tech., Subband/Transform Coding Using Filter Band Designs Based on Time Domain Aliasing Cancellation, ICASSP, 1987".
If the above-described DFT or DCT is used as a method for transforming a waveform signal to the spectrum, M independent real-number data are provided by performing transform on a time block consisting of M samples. To reduce the connection distortion between time blocks, each time block is usually overlapped with both adjacent blocks by M1 samples each. Therefore, on average, M real-number data are quantized and coded for (M–M1) samples in DFT or DCT.
On the other hand, if the above-described MDCT is used as a method for transforming a waveform signal to the spectrum, M independent real-number data are provided from 2M samples as a result of overlapping both adjacent time blocks by M samples each. Therefore, on average, M real-number data are quantized and coded for M samples in MDCT. A decoding device can reconstruct the waveform signal by performing inverse transform on each block of the code obtained by using MDCT and then adding the resulting waveform elements while letting them interfere with each other.
Generally, by elongating a time block for transform, the frequency resolution of the spectrum is enhanced and the energy concentrates at a specific spectral component. Therefore, by using MDCT in which each block is overlapped with both adjacent blocks by half each to perform transform with a longer block length and in which the number of resulting spectral signals is not increased from the number of the original time samples, more efficient coding can be carried out than when DFT or DCT is used. Moreover, by having each block have a sufficient long overlap with the adjacent blocks, the distortion between the blocks of the waveform signal can be reduced.
By quantizing the signal thus divided to each band by the filter or spectral transform, a band where quantization noise is generated can be controlled and more auditorily efficient coding can be performed by utilizing characteristics such as masking effect. By carrying out normalization for each band with the maximum value of absolute values of signal components in the band before performing quantization, more efficient coding can be performed.
The frequency division width in the case of quantizing each frequency component obtained by frequency band division is determined, for example, in consideration of the human auditory characteristic. Specifically, an audio signal may be divided into a plurality of bands (for example 25 bands) with broader bandwidths for higher-frequency bands which are generally called critical bands. When coding data of each band in this case, coding is carried out by using predetermined bit distribution to each band or adaptive bit allocation to each band. For example, when coding coefficient/factor data resulting from the above-described MDCT processing by the above-described bit allocation, the MDCT coefficient/factor data of each band resulting from MDCT of each of the blocks is coded by using an adaptive number of allocated bits.
For such bit allocation, the following two techniques are known. Specifically, "R. Zelinski and P. Noll, Adaptive Transform Coding of Speech Signals, IEEE Transactions of Acoustics, Speech, and Signal Processing, vol. ASSP-25, No.2, Aug. 1977", discloses bit allocation based on the magnitude of a signal of each band. In this system, though the quantization noise spectrum is flat and the noise energy is minimum, the actual perception of noise is not optimum because the auditory masking effect is not utilized. "M. A. Kransner, MIT, The critical band coder—digital encoding of the perceptual requirements of the auditory system, ICASSP 1980", discloses a technique in which a necessary signal-to-noise ratio for each band is obtained using auditory masking, thus performing fixed bit allocation. With this technique, however, even when measuring characteristics by using a sine wave input, a satisfactory characteristic value is not obtained because of fixed bit allocation.
To solve these problems, a high-efficiency coding device is proposed in which all the bits that can be used for bit allocation are divisionally used for a fixed bit allocation pattern predetermined for each small block and for bit allocation dependent on the magnitude of the signal of each block and in which the division ratio depends on a signal related to the input signal so that the proportion of division to the fixed bit allocation pattern is increased for a smoother spectrum of the signal.
According to this technique, if the energy concentrates at a specific spectrum, as in a sine wave input, the signal-to-noise ratio can be significantly improved as a whole by allocating many bits to a block containing that spectrum. Generally, since the human auditory sense is very sensitive to a signal having an acute spectral component, the improvement in the signal-to-noise ratio by using this technique is effective not only for improvement in the numerical value in measurement but also for improvement in the sound quality perceived by the auditory sense.
Many other techniques for bit allocation are proposed. As the auditory model is elaborated further and the coding device has a sufficient capability, more auditorily efficient coding is made possible. In these techniques, typically, a bit allocation reference value of a real number which realizes the signal-to-noise characteristic found by calculation with high fidelity is found, and an integer which approximates the reference value is used as the number of allocated bits.
In the specification and drawings of the Japanese Patent Application No. H5-152865 or WO94/28633 proposed by the present inventors, a method is proposed in which a tonal component that is particularly important in terms of the auditory sense, that is, a signal component with energy concentrated around a specific frequency, is separated from a spectral signal and coded separately from the other spectral components. This enables efficient coding of an audio signal etc. at a high compression rate while causing little auditory deterioration.
To construct an actual code string, first, quantization accuracy information and normalization factor (coefficient) information may be coded using a predetermined number of bits for each band on which normalization and quantization are performed, and then a normalized and quantized spectral signal may be coded. Moreover, the ISO/IEC 11172-3:1993(E), 1993 describes a high-efficiency coding system in which the number of bits representing quantization accuracy information is set to vary depending on the band. It is standardized that the number of bits representing quantization accuracy information is decreased toward higher frequency bands.
Instead of directly coding quantization accuracy information, a method is known in which quantization accuracy information is decided from normalization factor information in a decoding device. In this method, however, the relation between normalization factor information and quantization accuracy information is decided when the standard is set. Therefore, control of the quantization accuracy based on a more advanced auditory model cannot be introduced in the future. Moreover, if the compression rate to be realized is variable, the relation between normalization factor information and quantization accuracy information must be defined for each compression rate.
There is also known a method for more efficient coding by coding a quantized spectral signal using a variable-length code described in "D. A. Huffman, A Method for Construction of Minimum Redundancy Codes, Proc. I.R.E., 40, p.1098 (1952)".
Meanwhile, a software distribution method is known in which an acoustic signal or the like coded by the above-described methods is encrypted and broadcast or recorded to a recording medium so that only a person who purchased a key is permitted to listen to the signal. As an encryption method, for example, a method is known in which an initial value of a random-number sequence is given as a key signal for a bit string of a PCM (pulse code modulation) acoustic signal or a coded signal and then a bit string obtained by taking an exclusive OR between the generated random-number sequence of 0/1 and the bit string is transmitted or recorded to a recording medium. As this method is used, only a person who acquired the key signal can correctly reproduce the acoustic signal and a person who did not acquire the key signal can only reproduce noise. Of course, it is also possible to use a more complicated method as an encryption method.
However, in these scrambling methods, if there is no key or if software is reproduced by ordinary reproducing means, what is reproduced is noise and the content of the software cannot be grasped. Therefore, these method cannot be used for applications such as distributing a disc having music recorded thereon with relatively low sound quality and allowing a person who listens to the music on trial to purchase only a key for a tune which the person likes and to reproduce the tune with high sound quality, or allowing a person to listen the software on trial and then to newly purchase a disc on which the software is recorded with high sound quality.
Conventionally, in the case of encrypting a high-efficiency coded signal, it is difficult to prevent the compression efficiency from lowering while providing a code string which is significant to ordinary reproducing means. Specifically, in the case where a code string obtained by high-efficiency coding is scrambled as described above, only noise is generated by reproducing the code string. Moreover, if the scrambled code string is not conformable to the original high-efficiency coding standard, the reproducing means might not operate at all. On the other hand, if the quantity of information is reduced, for example, by utilizing the auditory characteristics in the case where a PCM signal is scrambled and then high-efficiency coded, the signal obtained by scrambling the PCM signal cannot necessarily reproduced when the high-efficiency coding is canceled. Therefore, it is difficult to correctly descramble the signal. For this reason, a method which enables correct descrambling must be selected at the sacrifice of the efficiency in the compression method.
Thus, the Japanese Publication of Unexamined Patent Application No. H10-135944 proposed by the present inventors discloses an audio coding system which enables trial listening without a key with respect to a narrow-band signal produced by encrypting only a high-frequency side of a spectral signal which is transformed from a music signal and then coded. Specifically, in this system, the high-frequency side is encrypted and bit allocation information on the high-frequency side is replaced by dummy data so that the true bit allocation information on the high-frequency side is recorded at a position which is neglected by an ordinary decoder. By employing this system, for example, it is possible to enjoy listening to only one's favorite music with high sound quality as a result of trial listening.
In the technique described in the above-described Japanese Publication of Unexamined Patent Application No. H10-135944, the security depends only on the encryption. Therefore, if the signal is decrypted, there is a possibility that the music of high sound quality can be listened to without charging any fee for it.
In the case of low quality (sound quality or image quality) of trial viewing/listening, what quality of signal can be enjoyed after the purchase is unknown and whether to purchase or not is difficult to decide. However, if trial viewing/listening with relatively high quality is made possible, many users may think they can enjoy the content well without purchasing it.

This patent is subject to a terminal disclaimer.

Signal reproducing apparatus and method, signal recording apparatus and method, signal receiver, and information processing method