A method, for determining the real distance separating an object and an optical detection system, includes, from several so-called reported distances respectively less than or equal to individual reference distances dependent respectively on modulation frequencies: in a first step, determining an initial deviation coefficient between the reported distances and incrementing the smallest of the reported distances with the corresponding individual reference distance; then in a second step, determining a current deviation coefficient between the current distances obtained in the preceding step and incrementing the smallest of the current distances with the corresponding individual reference distance; and in a third step, repeating the second step until all the current distances exceed a common reference distance greater than the individual reference distances.

Generally, a so-called indirect time-of-flight ("iToF") optical detection system delivers, in a detection field, a radiation of periodic modulated optical light from, for example, a vertical-cavity surface-emitting laser diode, commonly referred to by the person skilled in the art by the acronym " VCSEL", and indirectly measures the distance separating an object situated in the detection field and the so-called "iToF" system via a measurement of phase shift of the optical signal received after the reflection on the object relative to the emitted optical light radiation.
It is also possible to prolong collection of optical signal data over several periods of the emitted optical light radiation so as to improve the accuracy of the measurement.
On the one hand, the repeatability of such a system on the measurement of the distance is a linear function of the frequency of the modulated optical light radiation. It is therefore preferable to increase the frequency of the emitted radiation.
But, on the other hand, the maximum measurable distance of such a so-called "iToF" system depends directly on the frequency of the modulated optical light radiation. This maximum measurable distance decreases with the increasing of the frequency. Consequently, it is also preferable to limit the frequency of the emitted radiation so as to prolong the maximum measurable distance, particularly in demanding practical cases.
One possible solution for addressing this kind of contradictory problem is based on the use of a combination of multiple radiation frequencies.
More specifically, an optical detection system adapted to use such a combination emits sequentially, to an object situated in its detection field, several optical light radiations modulated at different frequencies and determines, respectively, several so-called reported distances, corresponding respectively to the optical light radiations modulated at different frequencies.
Each reported distance is less than or equal to a maximum measurable distance dependent on the corresponding modulation frequency. These reported distances can be different if the real distance separating the object and the optical detection system is greater than any one of the maximum measurable distances.
A consistency test is consequently necessary to determine the real distance from the reported distances.
However, conventional consistency tests generally require complicated methods, particularly if at least three different modulation frequencies are used, and generally result in environmental noise or standard deviations of the signals received after the reflections on the object to be measured that are unsatisfactory.
Thus, there is a need to propose a technical solution of low complexity for systematically measuring the real distance separating the object and the optical detection system from the reported distances by using the optical light radiations modulated at different frequencies so as to reduce the noise or the standard deviations mentioned above.

Method for determining the distance separating an object and an optical detection system, and corresponding system


An adaptive load control system includes: a load monitoring and control device configured to monitor operating conditions of a load connected to an electrical power grid, and transmit load operating condition data; and a head-end load controller configured to: receive the load operating condition data; obtain data from externals sources about external factors that influence the load operating conditions; and generate load control profiles based on the data from external sources that control a duty cycle for the load during a scheduled load control event. The load control profiles include instructions to increase the off time of the duty cycle for the load when the scheduled load control event overlaps a normal off time of the load, and one of the load control profiles is selected based on a comparison of the data from external sources and a forecast of external conditions during the scheduled load control event.

Utility companies, for example power companies, may institute load management programs to reduce peak loads on their power grids. Traditional load control is based on cycling loads such as air conditioners on and off. Typically, the cycling of these loads uses the same duty cycle setting for all loads regardless of the actual run-time of the load. For example, a heating, ventilating, and air conditioning (HVAC) unit for one residence may run 75% of the time, whereas an HVAC unit for a neighboring residence may run 50% of the time. The difference may be due to a difference in insulation or other differences between the units or the residences. If a utility initiates a load control event and specifies a 40% duty cycle for both residences (i.e., control the loads so they are off 40% of the time), it is possible that the residence with an HVAC unit running 50% of the time (and off 50% of the time) may not contribute to the load reduction since the 40% off cycle of the load control event may occur during the natural 50% off cycle of the HVAC unit. This may result in "free-riding" if the residence is not contributing to the utility peak load reduction, but still receives incentives from the utility for participating in the load management program.

Methods and systems for adaptive load control


Disclosed herein is a sectional warming blanket for patient warming having a structure comprising a first layer of material forming a bottom layer with openings to allow a profusion of air through the bottom layer, a second layer of material forming an upper layer wherein the upper layer is coupled to the bottom layer via a plurality of seals to form a plurality of interconnected air passageways, and an inlet located on the upper or bottom layers. In an embodiment, the sectional warming blanket further comprises an opening configured to receive a coupling device for coupling the sectional warming blanket to an additional sectional warming blanket. In another embodiment, the sectional warming blanket further comprises at least one outline formed from a portion of the structure, such that a section can be removed from the blanket and the blanket is re-sealed by a bonding mechanism along its periphery.

Patients who are preparing for, undergoing and recovering from a surgical procedure often require and are under the influence of anesthesia as part of the procedure. Due to the effects of the anesthesia, a patient may become unable to regulate their own core body temperature, a condition known as poikilothermia. Under these conditions, and when for example in an air-conditioned environment such as an operating room or a recovery area in a hospital or in a clinic, the lower air temperature and the need for the patient to be at least partially undressed may lead to the patient becoming hypothermic, wherein the core body temperature of the patient may begin to drop in an unintentional and undesirable manner.
One technique used to prevent hypothermia or other undesirable losses in body temperature of a patient when under the influence of an anesthetic is by the use of a forced air warming blanket or pad. The blankets or pads are generally constructed of a series of air passages and interconnected airways formed between two layers of material. The first layer of material is generally non-porous, and is formed on one side of the blanket or pad, and a second layer that is porous, or that includes distributed air-holes (e.g., perforations), is bonded in some fashion to the first layer of material to form the air passages and/or airways. The blanket or pad is configured to be coupled to a device that warms a flow of air to a predefined temperature range, and then directs that warmed air, using a relatively low pressure, into the air passages and/or airways, often through a flexible tube or duct that may also be formed of a non-porous material. The warm air provided into the air passages and/or airways is expelled at a slow rate though the porous material or out through the distributed air-holes provided by the second layer of material due to the low level of air pressure generated between the first and second layers of material.
By placing the blanket or pad for example over, underneath or in proximity to at least some portion or portions of the patient, the warmed air may be directed to the patient in a manner that assists the body of the patient in maintaining an acceptable core body temperature. Contact with the blanket or pad itself by a portion or portions of the body of the patient may also help assist the body in maintaining the core body temperate within acceptable limits.


An optical wireless communication device for transmitting data comprises a transmitter comprising a light source, a controller configured to control operation of the light source to produce modulated light comprising an optical wireless communication signal representative of said data, at least one proximity determining component configured to determine a proximity of an object, and a processing resource configured to determine whether the determined proximity is within a threshold distance, wherein the controller is configured to control operation of the transmitter and/or of at least one other component of the optical wireless communication device in dependence on whether the determined proximity is within the threshold distance.

Eye-safety constraints may impose restrictions on the power per solid angle of the light that light emitting devices radiate. Higher communication rates in optical wireless communications require more optical radiation to reach the optical detector, which translate into higher energy levels being emitted on the transmitter side for the same area coverage. At the same time, integration of communication interfaces into smaller devices leads to the requirement for smaller detectors, which further increases the required optical energy per unit of coverage area as the light collection area of the detector is reduced.
Eye-safety constraints may be defined in terms of overall light intensity that enters the human eye and, hence, in terms of the power per unit area (also referred to as irradiance) of the light at the human pupil. Hence, for any device that emits dispersed light, there is a minimum distance at which the light source is eye-safe, which is the distance at which the light intensity is within the allowed limits.
FIG. 1(a) presents an example where the power per unit area of the light reaching the human eye is too high. In this example, a transmitter 20 of the device emits optical signals 22, for example comprising infrared light. In this example, the intensity of light that enters the human eye 24 (e.g. the power per unit area at the human pupil) is too high and thus the device is not eye-safe at close proximity.
In an alternative configuration, as shown in FIG. 1(b), the same light is dispersed with a different design of transmitter optics 26, such that the light exiting the device is sufficiently dispersed to be eye-safe at close proximity. FIG. 1(b) shows a similar arrangement as in FIG. 1(a) with a transmitter 20 emitting optical signals 22, for example comprising infrared light, which reach a human eye 24. However, in this case the transmissive optics 26 disperse the light and reduce its intensity such that eye-safety constraints may be met. However, the use of dispersive optics can reduce the range and/or maximum data rate of optical wireless communications.


A gamma radiation detecting apparatus includes a gamma radiation collimator, a scintillation crystal, a charge coupled device, and an electronic device. The collimator receives and collimates gamma radiation. The scintillation crystal receives the gamma radiation from the gamma radiation collimator and converts the gamma radiation into visible light. The charge coupled device receives the visible light from the scintillation crystal and converts the visible light into an electrical charge. The electronic device converts the electrical charge into a digital image.

A. Field of Invention
The present invention relates generally to detecting gamma radiation and more specifically to gamma camera systems.
B. Description of the Related Art
It is known in the art to use gamma cameras to create multi-dimensional images of the distribution of gamma emitting sources for applications including, but not limited to, medicine, astronomy, and detection of contraband. Current state of the art photon counting, large field-of-view, imaging gamma cameras utilize a plurality of photomultiplier tubes optically coupled to one side or edge of a scintillation crystal. The other side of the scintillation crystal is exposed to the radioactive source to be imaged via a gamma-ray collimator. When a gamma-ray photon interacts within the crystal, visible light is emitted by the crystal at the point of the interaction. This visible light from the interaction strikes many photomultiplier tubes (PMT's). The position of the gamma interaction is mathematically determined by analyzing the outputs of the photomultiplier tubes and is well known in the art. The energy deposited in the crystal by the incident gamma ray is proportional to the total amount of visible light emitted by the crystal. This is determined by integrating the outputs of the photomultiplier tubes, also well known in the art.
While known gamma cameras function well for their intended purpose, there are limitations. Some disadvantages in the known technology include, but are not limited to, the following. Photomultiplier tube performance tends to drift with temperature and time making frequent calibration necessary. Photomultiplier tube performance depends on their position within the earth's magnetic field. Determination of the position of an interaction is difficult because the detection area of the PMT is much larger than the size of the scintillation event or interaction, resulting in an image with low spatial resolution. Scintillation crystal exchange is difficult due to the direct optical coupling of the PMT's to the crystal. Therefore, what is needed are apparatus and methods that overcome the limitations of the prior art. The present invention overcomes one or more of the disadvantages of the prior art.


A sample and hold circuit includes an operational amplifier; a sampling capacitor configured to sample input voltages at a plurality of different timings; an adding/subtracting unit configured to perform an adding or subtracting operation of the input voltages sampled by the sampling capacitor; and an offset voltage removing unit configured to remove an input offset voltage component of the operational amplifier from a voltage obtained by the adding or subtracting operation. The operational amplifier is configured to produce an output by holding the voltage from which the input offset voltage component of the operational amplifier has been removed by the offset voltage removing unit.

1. Field of the Invention
The present invention generally relates to sample and hold circuits and A/D converter apparatuses. Particularly, the invention relates to a sample and hold circuit suitable for use in a process of converting an input analog voltage into a digital value, and an A/D circuit including the sample and hold circuit.
2. Description of the Related Art
A sample and hold circuit is known in which an operational amplifier is used for performing a sampling and holding operation. In this type of a sample and hold circuit, the operational amplifier often employs a MOS transistor input configuration having a high input impedance. The operational amplifier of the MOS transistor input configuration, however, tends to have a large offset voltage compared to an operational amplifier having a bipolar input configuration because the element threshold voltage of the MOS transistor tends to have large variations. A method of cancelling the input offset of an operational amplifier involves sampling two voltages by two different capacitors, inverting the polarities of the two sampled voltages simultaneously, and then supplying the polarity-inverted voltages to the operational amplifier (see Non-Patent Document 1, for example).    Non-Patent Document 1: ISSCC Dig. Tech. Papers, pp. 318-319, 2007
In the offset cancelling method according to Non-Patent Document 1, because the two voltages are sampled by the different capacitors, parasitic capacitances that exist on the operational amplifier input end of the two capacitors do not necessarily correspond to each other. Thus, if the above offset cancelling method is used in the conventional sample and hold circuit mentioned above, an error due to the mismatch of the parasitic capacitances between the two capacitors would remain without being cancelled as an input offset of the operational amplifier. As a result, an accurate sample-and-hold output may not be obtained.

Sample and hold circuit and A/D converter apparatus


An endovascular anastomotic connector and method of using the same. The endovascular anastomotic connector includes a vascular conduit and a supply conduit. The vascular conduit has proximal and distal ends that reside within a vascular structure. The supply conduit extends at an angle from the vascular conduit. The proximal end of the supply conduit is configured to be attached to an auxiliary device.

The circulatory system of the human body transports blood containing chemicals, such as metabolites and hormones, and cellular waste products to and from the cells. This organ system includes the heart, blood, and a vascular network. Veins are vessels that carry blood toward the heart while arteries carry blood away from the heart. The human heart consists of two atrial chambers and two ventricular chambers. Atrial chambers receive blood from the veins and the ventricular chambers, which include larger muscular walls, pump blood from the heart. Movement of the blood is as follows: blood enters the right atrium from either the superior or the inferior vena cava and moves into the right ventricle. From the right ventricle, blood is pumped to the lungs via pulmonary arteries to become oxygenated. Once the blood has been oxygenated, the blood returns to the heart by entering the left atrium, via the pulmonary veins, and flows into the left ventricle. Finally, the blood is pumped from the left ventricle into the aorta and the vascular network.
In some instances, it becomes necessary to maintain fluidic communication with the vascular network. For example, a circulatory assist system uses a pump to aid in moving blood through the vascular network, thereby relieving the symptoms associated with congestive heart failure (commonly referred to as heart disease). The pump of the circulatory assist system includes inflow and outflow cannulae. Often the inflow cannula connects the left atrium of the heart to the pump; the outflow cannula connects the pump to a peripheral artery. The outflow cannula must be stabilized within the peripheral artery to ensure proper functioning of the circulatory assist system and reduce the risk of bleeding. Accordingly, it would be beneficial to have devices that can be delivered and secured to a peripheral vessel but are also capable of being attached to an auxiliary device.

Endovascular anastomotic connector device, delivery system, and methods of delivery and use


For an electromechanical machining of a work piece there is an optimal pulse duration for the machining pulses corresponding to the maximum copying accuracy. Such an optimal pulse duration corresponds to a certain value of the gap. By alternating the machining pulses with measurement pulses it is possible to obtain an accurate information about the gap dimensions on-line during the electrochemical machining process. The process control means (20) are used to automate the electromechanical machining, while keeping it in the optimal mode. For this purpose the process control means (20) comprise the pulse control unit (26) to establish the pulse duration of the voltage pulses to be applied across the gap (4).

The invention relates to a method for electrochemical machining of an electrically conductive work piece using an electrochemical machining device including a tool electrode opposing the work piece across a predetermined machining gap filled with electrolyte, the electrochemical machining device further comprising means for supplying machining voltage pulses across the machining gap.
The invention also relates to an arrangement for electrochemically machining an electrically conductive work piece by applying electrical machining pulses between the work piece and an electrically conductive electrode while electrolyte is supplied between the work piece and the electrode.
Electrochemical machining is a process in which an electrically conducting work piece is dissolved at the location of an electrode while electrolyte and electric current is supplied. For this purpose, the electrode is brought in the proximity of the work piece and, while electrolyte is fed into the gap between the work piece and the electrode, a powerful current is passed through the work piece and the electrode via the electrolyte, the work piece being positive with respect to the electrode. The current is applied in the form of machining pulses having a given amplitude and duration. In the intervals between the machining pulses, the electrolyte is renewed. Under the working conditions the work piece is being dissolved, thus increasing the value of the gap between the work piece and the electrode. To compensate for this, the electrode and the work piece are moved towards one another with a given feed rate, as a result of which the electrode forms a cavity or eventually a hole in the surface of the work piece, the shape of the cavity or hole having the shape corresponding to the shape of the electrode. This process can be used, for example, for making intricate cavities or holes in or for shaping hardened metals or alloys. The copying precision with which the shape of the cavity or the hole in the work piece corresponds to the shape of the electrode is important for the quality of the result.
A method for electrochemical machining is known from a patent application Publication WO 99/51382. According to the known method, in the intervals between the machining pulses and the passivation pulses for depositing passivation layers on the work piece are applied deliberately. By selecting a proper amplitude and duration of the passivation pulses, the spatial distribution of the passivation layer can be controlled. It is preferable to obtain the passivation layer with higher thickness at the lateral surfaces of the obtained cavity with respect to the passivation layer thickness at the front surface of the cavity. In this case, the dissolution rate at the front surface will be higher with respect to the lateral surfaces, which leads to a better copying accuracy.
The drawback of the known method for improving the copying accuracy is the difficulty associated with the selection of the values for the passivation pulse characteristics as well as gap dimensions with respect to both front and lateral surfaces of the cavity for obtaining a non-uniformly distributed passivation layer. The forming of the passivation layer is influenced by the local electrical field strength. Due to the field in-homogenities caused by the electrode curvature as well as by the precipitations on the cathode surface it is not possible to create the operational condition for an optimal copying accuracy.
It is an object of the invention to provide an electrochemical machining method with a further improved copying precision, where the process control can be optimized. To this end, the method of the present invention involves an application of a first number of the machining voltage pulses of predetermined optimal duration across the machining gap that is alternated with a second number of measurement voltage pulses across the machining gap in order to measure an actual value of the machining gap.
According to the technical measure according to the invention and based on a fundamental insight of the electrochemical processes in the gap, for each predetermined value of the gap there is a single optimal pulse duration, corresponding to the optimal local copying accuracy. It is understood that, for example in case of the adjacent cavities having different respective depths, the maximum copying precision can be achieved in case the local dissolution efficiencies vary substantially. Such an optimal operating condition is valid for a certain value of the gap. By alternating the machining pulses with measurement pulses it is possible to obtain an accurate information about the gap dimensions on-line during the electrochemical machining. In case the measurement of the gap dimensions shows a value deviating from a preset value, it is possible to alter the operating conditions by bringing the gap back to the predetermined value or by selecting another machining pulse duration, corresponding to the optimal pulse duration for the measured actual value of the gap. It is important to mention, that in case the measurement of the value of the gap positively deviates from the predetermined value, it is preferable to set the system back to the optimal operating conditions by reducing the value of the gap back to the predetermined value.
An embodiment of the method according to the invention is characterized in that the optimal duration of the machining voltage pulses is derived from the maximum value of a localization coefficient for the predetermined value of the machining gap. This technical feature is based on the insight that in case of adjacent cavities the maximum localization coefficient, corresponding to a ratio of local dissolution rates, results in the optimal copying precision. It is further understood that the local anodic dissolution rate is given by the local value of the current density, leading to the conclusion that the localization coefficient (L) is given by the ratio of local current density values J(xcfx84,si) as function of time and the value of the gap:                               L          =                                    J                                            (                                  τ                  ,                                      s                    1                                                  )                                                    J                                            (                                  τ                  ,                                      s                    2                                                  )                                                    ,                            (        1        )
where:
s1xe2x80x94is the value of the gap corresponding to the first cavity
s2xe2x80x94is the value of the gap corresponding to the second cavity.
Thus, in order to calculate the localization coefficient value, it is sufficient to use the information about the temporal behavior of the current density value as function of the gap. Further details are explained later with the reference to the figures.
Another embodiment of the method according to the invention is characterized in that a duration of the measurement voltage pulses is greater than the duration of the machining voltage pulses, the duration of the measurement voltage pulses being selected at least sufficient for a current density pulse across the machining gap to reach the global maximum. This technical measure is based on the fundamental insight that time corresponding with the global maximum of the current density pulse is a function of the absolute value of the applied voltage and the gap. For a given value of the applied voltage the time corresponding with the global maximum of the current density pulse is a direct measure of the absolute value of the gap. As will be explained in detail with reference to the figures the optimal pulse duration for the machining voltage pulses is shorter than the time corresponding to the maximum of the current density pulse. Therefore, the pulse duration for the measurement voltage pulses must be selected so that the global maximum in the current density pulse is reached. Knowing the actual gap dimensions from a previous measurement and using the information about the relation between the actual gap dimension and the corresponding optimal machining voltage pulse one can select the duration of the measurement pulse so that the resulting current density pulse across the gap reaches its global maximum. It is preferable for the polarity of the measurement voltage pulses to correspond to the polarity of the machining voltage pulses.
Another embodiment of the method according to the invention is characterized in that the value of the machining gap is corrected in case the actual value of the machining gap deviates from the predetermined value of the machining gap. Due to the fact that a predetermined value for the gap is selected to achieve a better dissolution and a surface quality of the work piece, it is preferable to correct for the deviation in the value of the gap, in case the measurements show that the actual value of the gap differs from the predetermined value. This gap correction can be performed with the electrode driving means available in the electrochemical machining device.
Another embodiment of the method according to the invention is characterized in that an interval between the machining voltage pulses is set to a value sufficient for renewal of the electrolyte in the machining gap. According to this technical measure it is assured that the operational conditions within the gap are fully recovered, it has been found that for an electrolyte comprising 5% NaCI and the operational conditions of the gap value of 30 xcexcm, applied voltage 50V and the electrolyte pressure of 300 kPa the recovery of the amplitude value of the current density is achieved after 300 xcexcs, while the recovery of the pulse form is obtained after 600 xcexcs. It has further been found that the renewal of the electrolyte is achieved after 600 xcexcs, the electrolyte flow being equal to 3 m/s.
A still further embodiment of the method according to the invention is characterized in that the value of the interval between the machining voltage pulses is derived from a system parameter including an amplitude value of the current density pulse across the machining gap and a time elapsed for the current density pulse to reach the amplitude value. It has been found that a decrease in the interval between the machining pulses leads first to a difference in the dissolution rates along the electrolyte flow followed by a creation of two separate zones. In the first zone every new machining pulse is given in a fresh electrolyte and in the second zone every new machining pulse is given into a heated electrolyte comprising a gaseous phase. This phenomenon causes pitting in the second zone, deteriorating the surface quality of the work piece. Therefore, it is concluded that in order to select the interval between the machining pulses it is more effective to use a system parameter including an amplitude value of the current density pulse across the machining gap and a time elapsed for the current density pulse to reach the amplitude value.
The invention further relates to an arrangement for electrochemically machining an electrically conductive work piece by applying electrical machining pulses between the work piece and an electrically conductive electrode while electrolyte is supplied between the work piece and the electrode.

Electrochemical machining method with optimal machining pulse duration


A method and apparatus is used for generating a perfectly random secret key between two or more transceivers in a wireless communication network. In a point-to-point system, both transceivers produce an estimate of the channel impulse response (CIR) based on the received radio signal. The CIR estimation is synchronized and may include error correction and detection. A long secret key of bits is generated from a digitized version of the CIR estimate, from which a perfectly secret encryption key is derived by privacy amplification.

Although many of the traditional cryptographic techniques may be applicable to wireless communications, these techniques suffer from the problem that the legitimate parties rely on the computational difficulty of obtaining a key by an eavesdropper, as opposed to its mathematical impossibility. As computational power available for eavesdropper increases, the effectiveness of such methods decreases. Additionally, such methods suffer from a problem that it is usually a simple matter to verify whether a particular guess is correct. Thus, it would be advantageous to construct a cryptographic technique that provides absolute (unconditional) secrecy, rather than one based on computational assumptions. One method for doing so has been well-known in prior art literature based on work of Maurer, Csiszar and Ahlswede and others. A brief description of the approach follows.
Suppose that two parties, Alice and Bob, have access to two sources of randomness, X and Y, which generate independent samples Xi and Yi, at predetermined times indexed by i. Suppose that Alice and Bob wish to generate a "perfectly secret" key by communicating over a public channel to which eavesdropper, Eve, has access. Moreover, Eve may also have access to another source of randomness, Z, generating independent samples Zi. The random source Z is presumably dependent on the random sources X and Y, but not as strongly as X and Y are cross-dependent on each other. Thus, intuitively, Alice and Bob share some advantage over Eve through the stronger inter-dependence of their random sources. Indeed it has been shown that Alice and Bob can exploit this dependence to generate a "perfectly secret" random key.
Without loss of generality, keys can be defined as bit sequences. A perfectly secret random key of length N bits is an N-bit sequence S, shared by Alice and Bob, such that anyone else's (in our case there is only Eve) estimation about what this key sequence can be is roughly equiprobably distributed over all possible N-bit sequences, of which there are 2N.
Let V denote all the communication which takes place over the public channel; n be the number of time instances over which each of the three parties accumulate the output of the random sources they have access to; |S| be the length of the resulting key. Then for any ε>0, we seek a protocol such that for sufficiently large n, the following relationship holds:
                                          1            n                                          H                                      (                                                S                  |                  V                                ,                Z                            )                                      >                                                          S                                      n                    -          ɛ                                    Equation                                                  1
where H is the entropy of a random variable, well known from prior art literature on information theory. Note that Equation 1 is normalized to a single sampling of the random sources as this is the basic resource for key generation.
The quantity
            1      n                  H                    (                              S            |            V                    ,          Z                )              ,which by equation 1 can be equivalently thought of as [|S|/n], is called the secret key rate. Hereafter, the notion of length of secret key and the secret key rate are interchangeable, as appropriate by the context. Namely, whenever a length of a particular secret key is noted, it is to be understood that this is derived based on the observation of some specific quantity (n) of the underlying random variables. Whereas, a secret key rate is noted, the notion is one of the average number of secret key bits per random variable observation.
It is worth noting that there is a critical difference between the above definition of secrecy and the one that most modern crypto systems, including all public-key systems, rely on. Specifically, modern crypto systems rely on the fact that it may be extremely difficult from a computational complexity point of view to guess the crypto key. However, in most of these systems, once the correct guess is produced it is very easy to verify that this is indeed the correct guess. In fact, the work of Maurer and Wolf implies that this must be so for any public-key system, i.e. one where the encryption key is made public, while the decryption key is kept secret. To illustrate the point, consider the following simple example of what a public-key crypto system might be based on, while keeping in mind that most practical systems are much more sophisticated.
Let p and q be two large prime number and let s=pq. It is known that the problem of factoring a product of two large prime numbers is computationally difficult. Thus, one might envision that a public-key cryptography system may be constructed by having the communication destination choose p and q in secret and make their product s publicly available, which is then used as an encryption key for some encryption system which cannot be easily decrypted unless p and q are known. An eavesdropper wishing to intercept an encrypted message would likely start by attempting to factor s, which is known to be computationally difficult. Presumably the eavesdropper would either give up or so much time would pass that the secrecy of the message will no longer be an issue. Note however, that should the eavesdropper guess p, it will quite easily verify that it has the right answer. This ability to know the right answer once it is finally guessed, is what separates computational secrecy from "perfect secrecy". Perfect secrecy means that even if the eavesdropper guesses the key correctly, it will have no ability to determine that it has indeed done so. Thus "perfect secrecy" is, in a very specific sense, a stronger notion of secrecy than what is prevalent in modern cryptography systems.
It is not obvious that such a protocol generating perfect secrecy in our scenario should exist. Nevertheless its existence, or the existence of many different protocols, has been established in the works of Ahlswede and Csiszar, Csiszar and Narayan and Maurer and Wolf. These prior works also give various upper and lower bounds on the number of random bits that can be generated per single sampling of the random sources under a wide range of assumptions.
The process for generating a perfectly secret key may then be outlined as follows. Alice and Bob first start by utilizing their joint randomness to establish a bit-string sequence S′ of whose inherent entropy from Eve's point of view is |S| bits with |S|≦|S′|. This is done using some number of public exchanges between Alice and Bob. In many cases, a single unilateral exchange is sufficient. The exact nature of the exchange depends on the nature of the jointly-random sources (X,Y,Z). This step is usually called information reconciliation.
Alice and Bob then possibly use another set of public exchanges, a single exchange is typically sufficient, to publicly agree on a function which transforms the sequence S′ into a perfectly secret string S. This is typically called privacy amplification. Alternatively, this function may be pre-agreed upon during the system design. In this case, it is assumed that Eve is aware of this.
An additional step occurring before the first step described above called advantage distillation may further be utilized, however as it is not pertinent here, nothing further is described in regards to it.
As specifically applied to a wireless communication system, the process needs further specification. While correlated random sources are a priori difficult to produce without prior communication, the wireless channel provides just such a resource in the form of the channel impulse response. Specifically, in certain communications systems, two communicating parties (Alice and Bob) will measure very similar channel impulse responses when communicating from Alice to Bob and from Bob to Alice (e.g., Wideband Code Division Multiple Access (WCDMA) Time Division Duplex (TDD) systems have this property). On the other hand any party not physically co-located with Alice and Bob is likely to observe a channel impulse response (CIR) that has very little correlation with that of Alice and Bob. This difference can be exploited for generation of perfectly secret keys. Also, it would be of interest to generate some number of perfectly secret bits per CIR measurement. Note that the CIR measurements have to be spaced fairly widely in time so as to be more or less independent.
Thus, there exists a need to design a system which explicitly extracts the secret bit string from a reciprocal wireless channel, while facing the challenge that under the worst case assumption applied in cryptography, an eavesdropper can intercept any bit exchanged between two wireless terminals, and is aware of the algorithm used by the two terminals to derive a secret key.
Yet another issue is that one may desire to extend the generation of a perfectly secret key from two transceiver terminals to a plurality of transceivers, such that the entire network of transceivers shares a common perfectly secret key, while only each pair shares the inherently unique channel properties. That is, each pair of transceivers generates a common random key, but these keys are different from pair to pair. This makes sharing information in such a network quite inefficient when the same information is to be broadcast to more then one receiver. The reason is that the message is encrypted with a different key for each receiver and thereafter appears as a different message and thus must be communicated separately to each receiver. In contrast, a message encrypted with a shared key can be multicast once and all of the legitimate receivers are able to decrypt the single transmission.

Generation of perfectly secret keys in wireless communication networks


A processing solution such as a developer and fixer is maintained at optimum processing ability by conducting electricity through an anion exchange membrane. In FIG. 1 , for example, an anion exchange membrane A1 and an only H.sup.+ and/or OH.sup.- permeable diaphragm M1 are disposed in a tank 11 to define three compartments 11a, 11b, 11c which are charged with electrolyte solution E1, developer Dev, and electrolyte solution E2 and have disposed therein anode 22, cathode 21 and anode 24, respectively. Silver halide photosensitive material is processed by passing it through the developer. Electricity is conducted between anode 22 and cathode 21 during processing and between anode 24 and cathode 21 during quiescent periods.

1. Field of the Invention
This invention relates to a photographic processing apparatus and method for processing photographic silver halide photosensitive material (often abbreviated herein as "photosensitive material").
2. Prior Art
Black-and-white photosensitive materials after exposure are processed through a series of steps including black-and-white development, fixation and washing and color photosensitive materials after exposure are processed through a series of steps including color development, desilvering, washing and stabilization. There are used black-and-white developer for black-and-white development, fixer for fixation, color developer for color development, bleaching, blix and fixing solutions for desilvering, city water or deionized water for washing, and stabilizer for stabilization. Photosensitive materials are generally processed by dipping them in the respective solutions which are normally adjusted to a temperature of 20.degree.to 50.degree. C.
Among these steps, the developing step is a step wherein a developing agent which is a reducing agent acts on exposed silver halide grains in the photographic emulsion for reducing Ag.sup.+ into Ag. Silver images are created in this way in black-and-white photography. In the case of color photography, an oxidant of color developing agent reacts with a coupler to form a dye image corresponding to the silver image. The developers experience a lowering of developing power due to deterioration by conversion of the developing agent into an oxidant with the progress of processing and by air oxidation of the developing agent and preservative during quiescent periods.
For avoiding such developer deterioration, a typical prior art approach is to replenish an increased amount of developer. Increased replenishment, however, results in increased usage of chemical agents and water, which is undesirable particularly from the standpoint of environmental protection requiring resource saving and waste liquid reduction. Further, since color developing agents are expensive, their increased consumption is against economy.
More often than not, the developing agents are organic compounds in both black-and-white photography and color photography. Developers containing organic developing agents undesirably cause silver stains with the progress of processing of photosensitive material probably because sulfites used as the preservative form silver sulfite with silver halide dissolved from the photosensitive material. This might be overcome by increasing the replenishment amount, which is undesirable from the standpoint of environmental protection as mentioned above.
As is also well known, metal compounds having reducing ability to exposed silver halide grains are effective for black-and-white developers. Such useful metal compounds include salts and complexes of transition metals such as vanadium, titanium, iron and chromium as disclosed in Journal of Japan Photography, 20 (2), 62 (1957); ibid., 19, 40 (1956), ibid. 29, 31 (1966), Photographic Industry, March, 67 (1976), Journal of the Japanese Chemical Society, No. 9, 1321 (1980), PSE, 19, 283 (1975), Japanese Patent Publication (JP-B) No. 41899/1979, Chiba University Engineering Faculty Technical Report, 14, 1 (1962), ibid., 21 (40), 169 (1970), ibid. 18, 39 (1967), ibid., 21 (39), 11 (1970), Japanese Patent Application Kokai (JP-A) No. 51731/1975, U.S. Pat. No. 3,942,985 and 3,938,978, UKP 1,462,972, JP-A 78534/1982, PSE, 12 (6), 288 (1968 ), and PSE, 14 (6), 391 (1970).
As compared with the organic developing agents, these metal compounds have the advantage that they can be used in acidic or neutral aqueous solutions at higher concentrations without incurring silver stains, but the disadvantage that the developers associated therewith change their oxidation reduction potential with the lapse of time or with the progress of development reaction, failing to maintain a stable activity level. Such a disadvantage can be overcome by increasing the replenishment amount as in the case of organic developing agents at the sacrifice of resource saving and waste liquid reduction.
On the other hand, fixation is to dissolve away the residual silver halide with a suitable dissolving agent for fixing a developed silver image in the case of black-and-white photography. In the case of color photography, silver halide resulting from oxidation of an unnecessary silver image is dissolved away in the bleaching step.
Therefore, the fixer contains a fixing agent which is a silver halide dissolving agent and a preservative. During quiescent periods, the fixing agent and preservative are subject to air oxidation with the lapse of time and on oxidation, they decompose to form sulfides which incur sulfide troubles such as staining of photosensitive material surface. When the fixing agent used is hypo, for example, silver thiosulfate would accumulate in the fixer during processing. Under-fixation or short desilvering would occur unless a fresh fixing solution is replenished in a sufficient amount to reduce the silver thiosulfate concentration in the fixer. In the case of color photography, the above-mentioned troubles due to oxidation are aggravated by entrainment of bleaching solution by photosensitive material.
A typical prior art solution to this problem is to increase the amount of fixer replenished in both black-and-white photography and color photography. Increased replenishment, however, is undesirable from the standpoints of resource saving and waste liquid treatment as previously mentioned.
Under the circumstances, we previously proposed in U.S. Ser. No. 07/730,719 (filed Jul. 16, 1991) or JP-A 273237/1991 a method for treatment of a developer containing an organic developing agent or a fixer by placing it in contact with an electrolyte solution through an anion exchange membrane, immersing a cathode in the developer or fixer and an anode in the electrolyte solution, and conducting electricity between the electrodes. With respect to a developer containing a metal compound as the developing agent, we previously proposed in Japanese Patent Application No. 24137/1991 a similar method of treating the developer by electric conduction.
These methods can treat the developer or fixer in a reducing atmosphere and remove Br.sup.- and other halide ions accumulating during processing by causing them to migrate from the developer or fixer to the electrolyte solution. This can advantageously maintain the development or fixation ability and is thus effective for reducing the replenishment amount.
One problem associated with these methods is that if electric conduction is made in the developer in order to prevent development ability lowering due to air oxidation during quiescent periods, then the developer is removed of Br.sup.- excessively and becomes more likely to fog. When the fixer is treated by the electric conduction method mentioned above, desilvering is short with some types of photosensitive materials, especially black-and-white photosensitive materials and plate-making photosensitive materials such as lithographic photosensitive materials. There is a need for a further reduction in replenishment amount.
In addition, the anion exchange membrane loses its processing ability during an extended period of use, that is, has a short life, especially with color developers containing higher contents of organic developing agents.

Photographic processing apparatus and method


A method for improving the exhaust-gas behavior of mixture-compressing internal combustion engines. The output signal of an oxygen measurement probe arranged in the exhaust gas channel of the internal combustion engine is divided within the voltage region in question into a number of sections and a corrected voltage value is stored in a memory for each section.

The present invention relates to a method of improving the exhaust-gas behavior of mixture-comprising internal combustion engines, in which the output signal of an oxygen measurement probe arranged in the exhaust gas channel of the internal combustion engine is fed to a controller the output voltage of which represents a setting variable for controlling the fuel-air ratio.
The invention furthermore relates to a device for the carrying out of the method.
In the art of preparing the fuel-air mixture for mixture-compressing internal combustion engines, it has been known for a long time to control the composition of the mixure as a function of the output signal of an oxygen measurement probe arranged in the stream of exhaust-gas in order to achieve the best possible elimination of noxious exhaust gases. In this case, the output signal of the oxygen measurement probe is fed to a controller, and the output voltage of the controller forms a setting variable for controlling the fuel-air ratio.
By the control of the fuel-air ratio of internal combustion engines, it is desired primarily to reduce noxious contents of the exhaust-gas emissions of internal combustion engines. For this purpose, a method is known, for instance, which employs an oxygen measurement probe arranged in the exhaust-gas stream of the internal combustion engine and controls an integrating device, the output signal of the exhaust-gas measurement probe being applied to a threshold switch, and switching the latter when the threshold valve is reached. The direction of integration of the integrating device is changed upon the switching of the threshold switch. The time constant of the integrating device is changed as a function of at least one operating parameter of the internal combustion engine, and particularly as a function of the amount of intake air of the internal combustion engine. The integrating device of variable time constant proposed in the case of the known method, however, does not satisfy all requirements with respect to precise and adaptable control. In particular, in the known method the setting variable does not follow sudden changes in loads sufficiently rapidly.
The voltage signal of an oxygen measurement probe typically has a steep course, in the region of lambda=1, which passes in each case into a flat branch directly adjoining this region. The voltage signal of the oxygen measurement probe acts on the means for forming the mixture in the manner that upon a signal from the probe which corresponds to a lambda of less than 1, the mixture is made leaner, while with a probe signal of more than 1, the mixture is made richer. As a result of the steep course of the characteristic curve, the control passes in quasi-steady state continuously through the region of the characteristic curve between the two points of inflection. On the average, the compostion of the mixture is such that it corresponds to the stoichiometric value and the exhaust gas can be substantially freed of undesired noxious portions by a catalytic exhaust-gas purification device.
Upon a sudden change in load, such as occurs frequently in the normal travel of an automotive vehicle, the value of the fuel-air ratio, lambda, can differ considerably from the desired value 1, primarily as a result of condensation processes in the intake region of the internal combustion engine. As a result of the flat course of the characteristic curve of the voltage value of the oxygen measurement probe with lambda values above or below a value of 1, however, only a relatively small disturbance signal is produced so that the control device only inadequately recognizes the actual deviation of the lambda value from the desired condition. Accordingly, the return of the control to the value of 1 takes an undesiredly long period of time and, during this time, the exhaust gases contain a high percentage of noxious substances. Furthermore, the continuous variation of the fuel-air ratio within relatively wide limits around a value of 1 results in a periodic change in the composition of the exhaust gas which must be counteracted in the following manner, namely, that both the exhaust-gas measurement probe and the catalytic after-treatment device for the purification of the exhaust gas are arranged at a minimum distance from the outlet of the internal combustion engine.
A method is already known in which a regulation in accordance with a stored typical field of characteristic curves is superimposed on the control of the fuel-air ratio. However, this method does not eliminate the difficulties inherent in the nonlinear course of the characteristic curve of the oxygen measurement probe. Furthermore, there is a considerable expense for memory in the electronic regulating device.

Method and device for improving the exhaust-gas behavior or mixture-compressing internal combustion engines


The present invention provides, as a gene encoding an antigen recognized by a G-CSF inducing antibody, a gene encoding any one of the following proteins: (a) a protein having an amino acid sequence shown in SEQ ID NO; 2; (b) a protein having an amino acid sequence comprising a deletion, substitution, addition or insertion of one or several amino acids with respect to the amino acid sequence shown in SEQ ID NO: 2, and having a binding ability for an antibody which induces and secretes a granulocyte colony-stimulating factor or a fragment thereof: or (c) a protein having at least 50% or more homology with the amino acid sequence shown in SEQ ID NO: 2, and having a binding ability for an antibody capable of inducing and secreting a granulocyte colony-stimulating factor or a fragment thereof.

Granulocyte colony-stimulating factor (G-CSF) has a molecular weight of approximately 18,000 to 22,000. This factor is a glycoprotein, which induces the differentiation and proliferation of one type of a blood component leukocyte, neutrophil. This glycoprotein is comprised of 174 amino acids (occasionally 178 amino acids) in the case of human, and it is composed of 178 amino acids in the case of mouse.
G-CSF affects to enhance the survival and function of mature neutrophils, the formation of erythroblasts by an erythropoietin, and the formation of blast cell colonies by interleukin-3. Moreover. G-CSF promotes (reinforces the function and increases the numbers of) blood cells such as leukocytes, erythrocytes or thrombocytes. Examples of the cells generating G-CSF include macrophages, stromal cells, monocytes, T lymphocytes, fibroblasts, vascular endothelial cells and others.
Administration of G-CSF as a therapuetic agent has an effect for treatment of neutropenia as a side effect of an anticancer agent, neutropenia occurring after bone marrow transplantation, and aplastic anemia. However, when G-CSF is administered, it requires frequent administration because of its low stability in the blood, and further, the administration route is limited to intravenous or subcutaneous administration. Therefore, the use of G-CSF as a therapeutic agent is painful for patients and imposing the burden to doctors. Moreover, it has been reported that bone ache occurs as a side effect when G-CSF is therapeutically administered. Direct administration of macrophages or stroma cells, which produce G-CSF, has not been carried out, since these cells happen to contain various types of proteins or substances and so unexpected side effects might occur.
As stated above, a method of differentiating and growing neutrophils by the direct administration of G-CSF elicits bone ache as a side effect and requires frequent administration, thereby giving a certain pain and burden to both patients and doctors. Accordingly, the development of another treatment method is strongly required, but it has not been established up till now.
Thus, the present inventors have intended that G-CSF is not directly administered but G-CSF is allowed to be produced and as a result neutrophils are differentiated and grown, and they have previously succeeded in providing a G-CSF-inducing antibody (Japanese Patent Application No. 9-266591 (Sep. 30, 1997) and Japanese Patent Laid-Open No. 11-106400 (Apr. 20, 1999). However, an antigen recognized by the G-CSF inducing antibody has not been clarified.

This patent is subject to a terminal disclaimer.

Proteins, genes encoding them and method of using the same


An apparatus for testing digital and analog signals from an integrated circuit includes an adder or subtractor 17 for being supplied with an analog signal outputted from the integrated circuit of a device under test and a signal outputted from a driver 11, an integrator 14 for being supplied with an analog signal outputted from the adder or subtractor 17, a switch 22 for selectively transmitting an analog signal outputted from the integrator 14 and a digital signal outputted from the integrated circuit to the comparator 13, and a switch 24 for selectively transmitting a signal outputted from a memory 20 and a signal outputted from a comparator 13 to the driver 11. At least one of the switches 22, 24 is operated depending on whether a signal to be tested is analog or digital.

1. Field of the Invention
The present invention relates to an apparatus for testing an integrated circuit (hereinafter referred to as xe2x80x9cICxe2x80x9d), and more particularly to an apparatus for testing an IC which comprises both digital and analog circuit components.
2. Description of the Related Art
One conventional IC testing apparatus is shown in FIG. 7 of the accompanying drawings. As shown in FIG. 7, the conventional IC testing apparatus has a power supply 1, a controller 2, a time-based synchronizing system 3 for synchronizing various measuring components with a given timing signal, and a device interface 4 for connecting the measuring components to an IC device under test. The conventional IC testing apparatus also has, as its measuring components, a digital I/O device (often a plurality of digital I/O devices) 5 for exchanging digital signals with a digital signal terminal of the IC device under test to determine whether the IC device under test is acceptable or not, an audio-band AWG (Arbitrary Waveform Generator) 6 and a video-band AWG 7 for applying known signals to an analog signal input terminal of the IC device under test, and an audio-band digitizer 8 and a video-band digitizer 9 for detecting a signal from an analog signal output terminal of the device under test to determine whether the IC device under test is acceptable or not. The conventional IC testing apparatus may have a plurality of AWGs and a plurality of digitizers having different bands and different resolutions depending on the signal frequency that is handled and the required level of accuracy.
For testing an IC device, the conventional IC testing apparatus applies a predetermined signal to the IC device under test, and compares an output signal from the IC device under test with an expected value. For testing an IC which comprises both digital and analog circuit components, it is necessary to perform a digital output test using a digital comparator and an analog output test using an analog comparator.
Specifically, a digital test signal generated by a digital signal generator is applied to the IC under test, and an analog signal outputted from the IC under test is converted by an analog-to-digital converter into numerical data, which is stored in a capture memory. Thereafter, a processor processes the numerical data stored in the capture memory to calculate parameters necessary to evaluate analog output characteristics of the IC under test, and determines whether the IC under test is acceptable or not using the parameters. A digital signal outputted from the IC under test is compared with a value expected from an acceptable IC by a digital signal evaluation apparatus to determine whether the IC under test is acceptable or not.
According to the above conventional process, different testing units are used to test digital and analog output signals from an IC which comprises both digital and analog circuit components. Therefore, it is necessary to test such an IC with two testers, i.e., a digital IC tester and an analog IC tester, or a single large-scale IC tester comprising digital and analog test circuits.
Conventionally, the test system needs to have optimum test devices for handling respective attributes (e.g., digital and analog natures, frequency bands, resolutions, etc.) of a signal applied to or outputted from a device under test. Furthermore, testing a variety of devices requires a number of test devices having different performances to be available on hand.
In each test, the test device must be connected to corresponding terminals of the device under test. Such connections may need to be changed depending on the item to be measured. Changing connections makes the test time-consuming because it causes mechanical connectors such as relays to be turned on and off. Since terminal layouts of devices under test generally differ from device to device, it is necessary to prepare connecting jigs dedicated for the respective devices under test.
According to the recent trends of multifunctional ICs, there is a growing number of ICs in which a large-scale digital circuit and a simple analog circuit are integrated. Preparing a large-scale analog testing circuit for use with ICs comprising digital and analog circuit components makes the cost of testing ICs high.
It is an object of the present invention to provide an apparatus of simple structure which has functions and performances that have been carried out by a plurality of conventional testing apparatuses.
According to the present invention, there is provided an apparatus for testing an integrated circuit in analog and digital components of a device under test by monitoring an analog signal and a digital signal outputted from the integrated circuit, comprising a comparator, a memory for receiving an output signal from the comparator, a driver for receiving an output signal from the memory, an adder or subtractor which may accept an analog signal outputted from the integrated circuit and a signal outputted from the memory, an integrator which accepts an analog signal outputted from the adder or subtractor, a first switch for selectively transmitting an analog signal outputted from the integrator and a digital signal outputted from the integrated circuit to the comparator, and a second switch for selectively transmitting a signal outputted from the memory and a signal outputted from the comparator to the driver, wherein at least one of the switches is operated depending on whether a signal to be tested from the integrated circuit of the device under test is an analog signal or a digital signal. The apparatus may further comprise a third switch and a digital filter which are connected between the comparator and the memory, for transmitting the signal outputted from the comparator selectively via the digital filter to the memory.
The present invention also provides an apparatus for testing an integrated circuit in analog and digital components of a device under test by monitoring an analog signal and a digital signal outputted from the integrated circuit, comprising a comparator, a memory for receiving an output signal from the comparator, a driver for receiving an output signal from the memory, an adder or subtractor which may accept an analog signal outputted from the integrated circuit and a signal outputted from the driver, an integrator which accepts an analog signal outputted from the adder or subtractor, a first switch for selectively transmitting an analog signal outputted from the integrator and a digital signal outputted from the integrated circuit to the comparator, and a second switch for selectively transmitting a signal outputted from the memory and a signal outputted from the comparator to the driver, wherein at least one of the switches is operated depending on whether a signal to be tested from the integrated circuit of the device under test is an analog signal or a digital signal. This apparatus may also further comprise a third switch and a digital filter which are connected between the comparator and the memory, for transmitting the signal outputted from the comparator selectively via the digital filter to the memory. The apparatus may further comprise a delay circuit connected between the comparator and the adder or the subtractor. The apparatus may further comprise a delay circuit connected between the comparator and the second switch. In the apparatus, the driver may be disposed in a feedback loop extending from the comparator to the adder or the subtractor.
The testing apparatus according to the present invention can test a plurality of items without changing connections between itself and the integrated circuit under test. If integrated circuits to be tested have terminals at identical positions, then the testing apparatus can test different integrated circuits without changing connections. The testing apparatus can thus test integrated circuits at a reduced test cost.
While it has generally been practiced to input a digital signal to and output a digital signal from one apparatus, the present invention makes it possible for one testing apparatus to input and output a digital signal and also to input and output an analog signal. The digital and analog signal inputting and outputting capability unifies the components enclosed by the dotted line in FIG. 7, i.e., the digital I/O 5, the audio-band AWG 6, the video-band AWG 7, the audio-band digitizer 8, and the video-band digitizer 9.

Apparatus for testing integrated circuits having an integrated unit for testing digital and analog signals


An optical pickup for recording and reproducing information on record media is provided. The pickup includes light sources corresponding to the record media, a drive circuit for driving one of the light sources, a switch for switching a connection between the drive circuit and one of the light sources, and a control circuit for controlling the drive circuit and the switch.

1. Field of the Invention
The present invention relates to an optical pickup and so on used for an information processing apparatus for optically performing recording, reproduction, erasure and so on of information.
2. Related Art of the Invention
In the case of recording and reproducing on a plurality of record media for recording and reproducing at different wavelengths respectively by a single apparatus, an optical pickup having a plurality of light sources of different wavelengths according to the types of the record media is generally used. FIG. 9 shows a configuration of the optical pickup in the past. Reference numerals 901 and 902 denote light source units of mutually different wavelengths, and though it is not shown, they are comprised of, for instance, a semiconductor laser, a hologram, a photo-detector and so on that are examples of the light sources as one piece. The light emitted from the light source unit 901 passes through a beam splitter (hereinafter, BS) 903, and then it is condensed on a record medium 905 by a condenser lens 904. The light reflected by the record medium 905 enters into the light source unit 901 by following a reverse optical path. The light incident on the light source unit 901 is diffracted by the hologram built into the light source unit, and various signals including focus, tracking and RF are detected by the photo-detector in the light source unit. However, the configuration of the inside of the light source units 901 and 902 and methods of detecting various signals are not substantial components of this technology and the present invention described hereafter, and also various configurations are already in the public domain, so that description thereof will be omitted.
The light emitted from the light source unit 902 is reflected by the BS 903 and then is condensed on the record medium 905 by the condenser lens 904. The light reflected by the record medium 905 enters into the light source unit 902 by following the reverse optical path, and the various signals are detected as with the light source unit 901. The BS 903 synthesizes and separates the lights from the light source units 901 and 902, where a band-pass filter for controlling reflection and transmission of the lights by the wavelength, a polarizing beam splitter for controlling them by polarization, a half mirror for separating them into a transmitted light and a reflected light at an arbitrary ratio and so on are generally used. The light source units 901 and 902 are connected to a drive circuit 906 and a control circuit 907, a drive circuit 908 and a control circuit 909 respectively, and the drive circuit supplies a current to the semiconductor laser that is the light source in the light source unit according to the signal from the control circuit so as to control light emission.
As this configuration in the past has the drive circuit and the control circuit provided to each light source unit, there are large amounts of circuitry in the entire optical pickup so that it has problems such as increased costs and upsizing of the apparatus.
An object of the present invention is to implement an optical pickup and so on for driving a plurality of light sources with a small amount of circuitry and having high-performance drive characteristics.
One aspect of the present invention is an optical pickup for recording and reproducing information on a plurality of record media respectively, said pick up having:
a plurality of light sources corresponding to said plurality of record media;
a drive circuit of driving one of said plurality of light sources;
switching means of switching a connection between said drive circuit and one of said plurality of light sources; and
a control circuit of controlling said drive circuit and said switching means, and wherein:
as for transmission line lengths between said switching means and said plurality of light sources, the shorter a wavelength of the light source is, the shorter the transmission line length thereof is.
Another aspect of the present invention is an optical pickup for recording and reproducing information on a plurality of record media respectively, said pickup having:
a plurality of light sources corresponding to said plurality of record media;
a plurality of drive circuits of driving said plurality of light sources respectively;
switching means of switching a signal from the outside to one of said drive circuits and outputting it; and
a control circuit of controlling said drive circuits and said switching means, and wherein:
as for transmission line lengths between said switching means and said plurality of light sources, the shorter a wavelength of the light source is, the shorter the transmission line length thereof is.
Still another aspect of the present invention is the optical pickup, wherein, when the wavelength of the light source of the shortest wavelength, of said plurality of light sources, is xcex1 and the wavelengths of the other light sources are xcex2, xcex3, . . . xcexn (n=2, 3, 4 . . . ) in increasing order of wavelength, and the transmission line lengths between said plurality of light sources and said switching means are L1, L2, L3, . . . Ln in increasing order of wavelength, there is a relationship, between the wavelengths and the transmission line lengths, of L1/L2 less than xcex1/xcex2, L1/L3xe2x89xa6xcex1/xcex3, . . . L2/Lnxe2x89xa6xcex1/xcexn.
Yet still another aspect of the present invention is an optical pickup having:
a first light source of recording or reproducing information on a record medium;
a second light source of reproducing the information from said record medium;
a drive circuit of driving said first light source or second light source;
switching means of switching a connection between said drive circuit and said first light source or second light source; and
a control circuit of controlling said drive circuit and said switching means, and wherein:
a transmission line length between said switching means and said first light source is shorter than that between said switching means and said second light source.
Still yet another aspect of the present invention is an optical pickup having:
a first light source of recording or reproducing information on a record medium;
a second light source of reproducing the information from said record medium;
a first drive circuit of driving said first light source;
a second drive circuit of driving said second light source;
switching means of switching a signal from the outside to said first drive circuit or said second drive circuit and outputting it; and
a control circuit of controlling said first drive circuit, said second drive circuit and said switching means, and wherein:
a transmission line length between said switching means and said first light source is shorter than that between said switching means and said second light source.
A further aspect of the present invention is the optical pickup, wherein said first light source is plurality of light sources corresponding to a plurality of record media, and as for transmission line lengths between said switching means and said plurality of light sources, the shorter a wavelength of the light source is, the shorter the transmission line length thereof is.
A still further aspect of the present invention is the optical pickup, wherein, when the wavelength of the light source of the shortest wavelength, of said plurality of light sources, is xcex1 and the wavelengths of the other light sources are xcex2, xcex3, . . . xcexn (n=2, 3, 4 . . . ) in increasing order of wavelength, and the transmission line lengths between said plurality of light sources and said switching means are L1, L2, L3, . . . Ln in increasing order of wavelength, there is a relationship, between the wavelengths and the transmission line lengths, of L1/L2xe2x89xa6xcex1/xcex2, L1/L3xe2x89xa6xcex1/xcex3, . . . L1/Lnxe2x89xa6xcex1/xcexn.
A yet further aspect of the present invention is the optical pickup, wherein said drive circuit and said switching means are configured as one piece.
A still yet further aspect of the present invention is the optical pickup, wherein said light sources and said switching means are configured as one piece.
An additional aspect of the present invention is the optical pickup, wherein said n is 2 or 3.
A still additional aspect of the present invention is an information processing apparatus having:
an optical pickup according to any of 1st to 10th inventions;
demodulation means of demodulating a signal obtained from said optical pickup; and
modulation means of modulating the signal to be outputted to said optical pickup.
A yet additional aspect of the present invention is an optical information recording and reproducing method of recording and reproducing information on a plurality of record media respectively, said method having:
a driving step of driving any one of a plurality of light sources corresponding to said plurality of record media;
a switching step of switching a connection of any one of said plurality of light sources in said driving step; and
a controlling step of controlling said driving step and said switching step, and wherein:
as for transmission line lengths of said plurality of light sources in said switching step, the shorter a wavelength of the light source is, the shorter the transmission line length thereof is.
A still yet additional aspect of the present invention is an optical information recording and reproducing method of recording an reproducing information on a plurality of record media respectively, said method having:
a plurality of driving steps of driving a plurality of light sources corresponding to said plurality of record media respectively;
a switching step of switching a signal from the outside to one of said driving steps and using it; and
a controlling step of controlling said driving step and said switching step, and wherein:
as for transmission line lengths of said plurality of light sources in said switching step, the shorter a wavelength of any one of said plurality of light sources is, the shorter the transmission line length thereof is.
A supplementary aspect of the present invention is the optical information recording and reproducing method, wherein, when the wavelength of the light source of the shortest wavelength, of said plurality of light sources, is xcex1 and the wavelengths of the other light sources are xcex2, xcex3 . . . xcexn (n=2, 3, 4 . . . ) in increasing order of wavelength, and the transmission line lengths of said plurality of light sources are L1, L2, L3, . . . Ln in increasing order of wavelength thereof, there is a relationship, between the wavelengths and the transmission line lengths, of L1/L2xe2x89xa6xcex1/xcex2, L1/L3xe2x89xa6xcex1/xcex3, . . . L1/Lnxe2x89xa6xcex1/xcexn.
A still supplementary aspect of the present invention is an optical information recording and reproducing method having:
a driving step of driving a first light source for recording or reproducing information on a record medium and a second light source for reproducing the information from said record medium;
a switching step of switching said first light source or second light source in said driving step; and
a controlling step of controlling said driving step and said switching step, and wherein:
a transmission line length of said first light source in said switching step is shorter than that of said second light source.
A yet supplementary aspect of the present invention is an optical information recording and reproducing method having:
a first driving step of driving a first light source for recording or reproducing information on a record medium;
a second driving step of driving a second light source for reproducing the information from said record medium;
a switching step of switching a signal from the outside to said first driving step or said second driving step and outputting it; and
a controlling step of controlling said first driving step, said second driving step and said switching step, and wherein:
a transmission line length of said first light source in said switching step is shorter than that of said second light source.
Thus, it is become possible to drive a plurality of light sources with small amounts of circuitry and to implement excellent driving characteristics.
And, they have an effect that makes possible to drive a plurality of light sources with small amounts of circuitry. Moreover, by configuring switching means and driving circuit or light source as one piece, it possible to miniaturize, to make low cost and to make high quality an optical pickup and an information processing apparatus.

Optical device for recording and reproducing information

Abstract: With respect to transmission line lengths between the switch and the light sources, the shorter a wavelength of a light source, the shorter the corresponding transmission line length.

Matsushita Electric Industrial Co., Ltd.


A fiber optic arrangement includes a primary strand, a plurality of secondary connection strands, each of which is coupled to the primary strand at a notch. Tight buffer optical fibers are attached, one at the end of each of the secondary connection strands.

1. Field of the Invention
This application relates to fiber optic cables. More particularly, this application relates to tight buffer fiber optic cable for conduits.
2. Description of Related Art
In the area of fiber optic cables, fibers, such as tight buffered optical fibers, are frequently bundled into packages so that they can be easily installed within conduits. For example, rectangular conduits are often used along dwelling units, apartments etc . . . . Within these conduits tight buffer fibers are installed in bundled packages. Periodically one fiber from the bundle is pulled out for entry into a specific dwelling unit for installation.
One current prior art solution is shown in FIG. 1. In this arrangement seven tight buffer fibers are each placed within a subunit (extra aramid strength embers and an additional jacket over the tight buffer fiber), which are then assembled into a group of subunits forming a bound assembly. This allows groups of fiber/subunits to be easily installed in conduits along dwelling units. However, to access one subunit/fiber in this bound assembly, first the binder for the assembly needs to be removed or cut and the fiber/subunit needs to be removed (from under the binder). Additionally, to get to the tight buffer fiber itself, the subunit (extra jacket and aramid fibers) must be opened and the tight buffer fiber core needs to be removed from the surrounding aramids.

Tight buffer fiber optic cables for conduits


A tone to which resonance characteristics have been added to is repetitively delayed so as to reverberate. The delay of the tone is determined based on the resonance characteristics, and a modified tone in which the reverberation and resonance characteristics are related to one another is generated.

1. Field of the Invention
The present invention relates to a reverberating/resonating apparatus and to a method thereof and, particularly, to an apparatus and method for adding resonance and reverberation to a generatied tone.
2. Related Art
A conventional reverberating apparatus employs a delay circuit. A tone that is generated (direct sound) is input to the delay circuit and is delayed (early reflection sound). The delayed output is further fed back to the delay circuit, so that the output is delayed repetitively (late reverberation).
Reverberating apparatuses of this type have been disclosed in Japanese Patent Applications Nos. 29477/1996, 46158/1996, 46159/1996 and 57174/1996, for example. An apparatus for adding resonance sound has been disclosed in Japanese Patent Application No. 314818/1989 (Japanese Unexamined Patent Publication (Kokai) No. 174590/1991).
However, these reverberating apparatuses add reverberation without establishing any relationship between the reverberation and the resonance. If the reverberation characteristics can be related to the resonance characteristics, there can be musical tones that are generated with a plurality of variations.

Reverberating/resonating apparatus and method

Kawai Musical Instruments Mfg. Co., Ltd.


In one embodiment, a method includes determining a number of initial servers in a massively parallel processing (MPP) database cluster and determining an initial bucket configuration of the MPP database cluster, where the initial bucket configuration has a number of initial buckets. The method also includes adding a number of additional servers to the MPP database cluster to produce a number of updated servers, where the updated servers include the initial servers and the additional servers and creating an updated bucket configuration in accordance with the number of initial servers, the initial bucket configuration, and the number of additional servers, where the updated bucket configuration has a number of updated buckets. Additionally, the method includes redistributing data of the MPP cluster in accordance with the updated bucket configuration.

Massively parallel processing (MPP) database management systems scale by distributing data to servers and running individual transactions on multiple servers. MPP databases distribute data and queries to multiple servers for high throughput and low latency. A shared nothing architecture scales by adding new servers for cluster expansion. MPP databases may enlarge storage and computational capacity by adding more servers. When scaling by adding servers, the distribution of data to the new servers is to be performed. Slower servers may dominate performance, which may be exacerbated by uneven data distribution. The workload of a server may depend on the amount of data stored.

System and method for massively parallel processor database


An injection tip assembly 10 and methods for use more reliably provide for delivery of fluid substances, such as materials that promote removal, destruction, or isolation of contaminants, into targeted zones within soil or bedrock. The injection tip assembly 10 permits the application of pressurized fluid 163 so as to erode or cut a desired cavity or eroded volume 164 within the subsurface 14, allows for timely observation, adjustment, and control of pressure within the cavity, and directs the delivery of a second substance or fluid that may incorporate desired materials. The consequence of managed erosion and pressure control is to nucleate and propagate a hydraulic fracture of desirable form that optimally delivers remedial agents throughout the targeted formation.

When ground, soil, or any subsurface becomes contaminated, remediation of the area is often considered. Heretofore, many methods of remediation of a contaminated subsurface required drilling a generally vertical bore hole from a surface into the contaminated subsurface, removing the boring device, and encasing the hole with a liner or casing, for example polyvinylchloride (PVC) piping. Thereafter, a remediation agent was delivered to the bottom of the bore hole through the PVC pipe casing. This technique has limited effect because of the small application area provided to the remediation agent at the bottom of the bore hole.
It was discovered that prior to delivery of the remediation agent through the PVC pipe casing, a jet cutting machine may be lowered into the bottom of the bore hole to cut various patterns in the contaminated subsurface to create a larger application area for the remediation agent. However, this technique has several drawbacks. One drawback is the PVC pipe casing limits the effectiveness and the spray pattern or the expulsion of the pressurized fluid. Another drawback relates to the runoff of the pressurized fluid after exposure to the contaminated subsurface, which must be transferred out of the bore hole in a controlled manner. Further, application of pressurized fluid into the bottom of the bore hole increases pressure inside the contaminated subsurface which leads to hydraulic fracturing of the subsurface in an uncontrolled manner.
The invention of more powerful direct push machines motivated the integration of injection nozzle orifices into the tip of a probe rod, which eliminates the need for drilling and depositing a PVC casing inside the bore hole. Using modern injection tips connected to probe rods, remediation agents are directed through probe rods and the nozzle orifice to apply the remediation agent to the contaminated substructure.
U.S. Pat. No. 5,733,067 issued to Hunt et al. is incorporated herein by reference to provide additional background information on problems faced when remediating a contaminated subsurface. Hunt et al. describes a method and system for bioremediation of contaminated soil using inoculated support spheres.

Injection tip and method for nucleating and propagating hydraulic fractures from probe rods


The present invention discloses a sectional external enclosure, comprising: a bottom plate having a bottom hole at each of its four comers, at least one positioning hole on each of its both sides, and a connecting hole/groove corresponding to a screw hole at the bottom of its periphery; two corresponding side panels, each having at least one positioning latch extended from its bottom and being inserted in the positioning hole; a fixing hole disposed on each end and passing through the bottom hole with a connecting member and secured to the fixing hole; an embedding groove disposed on the inner end of the rear side of the two side panels; a rear panel, vertically disposed at the rear end of the two side panels, and a guide latch protruded from both sides of the rear panel being inserted into the embedding groove for the positioning, and a plurality of through holes on the panel corresponsive to the surface of the signal connecting device for accommodating and positioning the rear panel to constitute the signal connection with the computer; a top panel having a top hole at each of its four comers and a connecting member passing through the top hole to fix the top panel onto the fixing hole such that the panels being enclosed into an external enclosure.

1. Field of the Invention
The present invention relates to an external enclosure, more particularly to a sectional external enclosure for accommodating computer peripheral devices.
2. Description of the Related Art
Computer is common to our life, and brings us much convenience. Any slow manual operation such as computation, file management, data storage, and data search can improve their efficiency with computer applications. Therefore, the blooming of computer is basically another wave of xe2x80x9cIndustrial Revolutionxe2x80x9d.
As the computer application becomes more popular, the communications, and multimedia applications of desktop computers and compact notebook computers utilize peripheral devices such as the 5.25-inch CD ROM, DVD ROM, CD-R, and CD-RW drives as well as mobile racks and interfaces such as the USB and IEEE 1394 (Fire Wire) interfaces for fast transmissions. Therefore, it is no longer a dream to use external enclosures for the connection of computers and peripheral devices.
Traditional computer external enclosures mainly use two sidewalls of an upper casing and a lower casing to respectively mount onto a fixed board, and a peripheral device such as an optical disk drive of the 5.25-inch specification is fixed between the two fixed boards by screws. The computer external enclosure of this type has been sold for years and that is the only choice. However, there is a shortcoming that the way of adjusting the position and securing the casings, fixed boards, and peripheral devices always troubles the computer users. Therefore, the inventor of the present invention has provided a solution as disclosed in the Taiwanese Utility Model Patent No. 178536 (foreign counterpart, Chinese Utility Model Patent No. 01200391.3). In view of the current existing computer external enclosures, it is difficult to break through its style, and the way of adjusting and positioning the fixed boards and peripheral devices for their combination needs to be improved.
The primary objective of the present invention is to provide a sectional external enclosure which comprises a bottom panel, two side panels, a rear panel, and a top panel; wherein the bottom and top panels are coupled with the four corners of the two side panels, and the rear end of the two side panels has an embedding groove for embedding and securing a rear panel, and finally a peripheral device is secured on the bottom panel to complete the assembling of the section external enclosure in accordance with the present invention. Such arrangement makes the assembling procedure very quick and convenient without any trouble of adjusting and positioning the fixed board.
The secondary objective of the present invention is to provide a sectional external enclosure, of which the two side panels and the rear panel have stylish design on the external surface, such as the design of horizontal decorative channels to enhance the artistic look of the external enclosure, and the modular design for the components of this invention can greatly reduce the volume of packing material and the assembling procedure for manufacturers.
A further objective of the present invention is to provide a sectional external enclosure, of which the two side panels has a pair of embedding grooves at its front end for fixing the two latches of a front panel to seal the opening end of the external enclosure.
Another further objective of the present invention is to provide a sectional external enclosure, of which the bottom panel is preferably made of metal boards and each of the rest of panels has a thin metal sheet attached on its inner wall to provide the functions of dissipating heat and preventing electromagnetic interference in order to comply with the requirements of safety regulations.
In view of the above description, the present inventor herein with many years of practical experience in the design, development, manufacturing and marketing of computer peripherals enhances the design of the external enclosure by performing a series of researches and developments and finally succeeds to invent the sectional external enclosure of the present invention.

11F-2, No. 11, Lane 202, Jing-Shing Road, Wen-Shan D1