Methods, devices and computer program products facilitate the extraction of embedded watermarks in the presence of content distortions. Pre-distorted synchronization templates are used to detect synchronization portions of embedded watermark frames. A pre-distorted synchronization template that best matches the synchronization portion of the embedded watermark frame produces an estimation of one or more distortions that are present in the content. The remainder of watermark frame can be evaluated based on the outcome of the comparison.

This section is intended to provide a background or context to the disclosed embodiments that are recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Watermarks are substantially imperceptible signals embedded into a host content. The host content may be any one of audio, still image, video or any other content that may be stored on a physical medium or transmitted or broadcast from one point to another. Watermarks are designed to carry auxiliary information without substantially affecting fidelity of the host content, or without interfering with normal usage of the host content. For this reason, watermarks are sometimes used to carry out covert communications, where the emphasis is on hiding the very presence of the hidden signals. In addition, other widespread applications of watermarks include prevention of unauthorized usage (e.g., duplication, playing and dissemination) of copyrighted multi-media content, proof of ownership, authentication, tampering detection, content integrity verification, broadcast monitoring, transaction tracking, audience measurement, triggering of secondary activities such as interacting with software programs or hardware components, communicating auxiliary information about the content such as caption text, full title and artist name, or instructions on how to purchase the content, and the like. The above list of applications is not intended to be exhaustive, as many other present and future systems can benefit from co-channel transmission of main and auxiliary information.
Designing a watermarking system requires reaching the proper balance between transparency (imperceptibility) of embedded watermarks, robustness of embedded watermarks (i.e., the watermark's ability to withstand intentional and unintentional signal distortions) and security requirements of the system (i.e., the extent to which embedded watermarks can evade detection, deletion and/or manipulation by unauthorized parties). Such a balancing act must be carried out while limiting the average and/or maximum number of processing operations (i.e., the processing load) and memory usage below particular levels that are often imposed for practical software and/or hardware implementations of watermark embedder and/or a watermark extractor.

Watermark extraction based on tentative watermarks


The present invention provides a dynamic model parameter identification system consisting of a parameter classifying part and a motion planning part. The parameter classifying part approximates the respective links forming the manipulator by means of a symmetrical and homogeneous virtual solid link, calculates the inertial parameters, and finally classifies the calculated inertial parameters into parameter groups. The motion planning part calculates the condition number for the parameter coefficient sub-matrix, and calculates the number of equilibriums which is shown by the quotient of the maximum and minimum values of the vector normal of the rows of the coefficient sub-matrix. The motion planning section then sets the motion for parameter identification so that the condition number and number of equilibriums are both below predetermined values. Therefore, it is possible to identify the dynamic parameters of a robotic manipulator with a high degree of accuracy and without carrying out numerous trial-and-error experiments.

1. Field of the Invention
The present invention relates to a dynamic model parameter identification system for accurately estimating dynamic models required in dynamic control introduced in order to operate a robotic manipulator accurately and at high speed.
2. Background Art
As a result of developments in robotic technology, robotic manipulators have recently been used not only for spot welding and for inserting simple parts in assembly operations, but also for such tasks as arc welding, painting, and sealing-jobs that require high speed and high accuracy. Therefore, higher and more precise performance from robotic manipulators is desirable in order to increase the productivity of these operations. For this reason, it will be necessary to actively compensate the effect of nonlinear dynamics which can be significant in the high speed, high accuracy motion of robotic manipulators of the high reduction ratio type. However, it is not possible to sufficiently satisfy this demand with conventional methods wherein in, for example, independent proportional derivative control system is employed for each joint. With the objective of resolving this problem, there have been proposed a variety of dynamic control methods, the computed torque method being one representative of these. The principal task of these dynamic controls is to calculate the joint torques necessary for the control of given trajectories and at given speeds. Accordingly, when moving a robotic manipulator along a trajectory generated in real time using sensors or the like, it is necessary to carry out these calculations in real time at a high speed, and the sampling time required would be 15 times the eigen-frequency of the manipulator mechanism. With the recent developments of high-speed processors like DSP and of newly developed parallel processing algorithms, however, high-speed computation for dynamic control has become possible.
Accurate dynamic models for robotic manipulators are necessary for carrying out dynamic control. More concretely, in addition to such geometric parameters as link length, dynamic parameters such as link mass, inertial tensor, and first-order moment must be identified. Although geometric parameters can be identified according to static position and orientation measurements of the robotic manipulator, it is not possible to identify dynamic parameters by static measurements, and is still difficult even when the robotic manipulators are designed using such sophisticated design tools as CAD systems. Moreover, there are few commercial robotic manipulators whose dynamic parameters are publicly available.
In order to resolve such problems as mentioned above, research regarding the identification of dynamic parameters has been widely carried out. From this research there has been proposed a sequential identification method wherein parameters are sequentially identified from a plurality of tests which are determined according to the structural configuration of the robotic manipulator under consideration. Further, it has been clarified that it is possible to derive a linear input-output equation relating to dynamic parameters from equations of motion for robotic manipulators of the revolving joint type. In this method, dynamic parameters are identified by measuring joint torques and joint angular position, velocity and acceleration, when all the joints are driven at the same time. However, the fundamental problem with these methods is that there are parameters that do not contribute to the joint torques and that there are redundant parameters that only contribute as linear combinations with other parameters. For this reason the concept of base parameters as non redundant parameters was proposed, and research was carried out on the base parameters of serial link type robotic manipulators and base parameters of closed link type robotic manipulators. From this research, a procedure was proposed which used a covariance matrix of nonlinearity to derive the principal base parameters contributing predominantly to the joint torques.
With regard to the principal base parameters of serial link type and closed link type robotic manipulators, the history of theoretical study is still relatively new, and sufficient experimentation has not yet been carried out. Moreover, although there are some experimental studies that have been done using simple direct-drive manipulators with little friction, there are few studies of the highly geared manipulators widely used in industries. In these studies, the sequential identification method was applied to the basic three degrees of freedom of an industrial manipulator with DC motors and harmonic drive mechanisms implemented in its joints, and it was shown that the viscosity friction coefficient and Coulomb's friction coefficient are not reliant on the orientation of the robotic manipulator but are almost constant in the tested cases. Other experimental studies have been performed on the Puma 760. These concluded that the controlling parameters for torque were the Coulomb friction terms and the diagonal terms of the inertial matrix, and that, because of the large size of the manipulator, it was difficult to excite the inertial dependent parameters and, as a result, these parameters could not be separated from the gravitational parameters. The studies described so far have used the sequential identification method for which the test procedure is complicated but for which the identification operation is easily arranged. Moreover, when the sequential identification method is employed, it has also been pointed out that errors easily accumulate. In contrast, there are few corroborative reports for the simultaneous identification method, which is a superior method with respect to the fact that the necessary parameters can be simultaneously inferred. In particular, with regard to the simultaneous identification method, the preferable operation for accurate identification is not clear, and in a manipulator with multiple degrees of freedom, the number of dynamic model parameters inevitably increases and, thus, the identification becomes even more difficult. For this reason, in spite of the appearance of such high speed processors as DSP, the application of dynamic control to industrial robotic manipulators is still a difficult matter.
In the conventional art, because there is not means for intrinsically selecting the parameters which have a controlling effect on the control capacity, great labor cost is required to identify the parameters. Further, in the conventional art a means for easily providing the preferable operation for parameter identification is not provided, therefore the highly accurate identification of parameters is difficult.

Dynamic model parameter identification system

Nippon Telegraph and Telephone Corporation


A sensor system for determining at least one rotation characteristic of an element rotating around at least one rotation axis. The sensor system includes at least one sensor wheel, which is connectable to the rotating element, the sensor wheel having a sensor wheel profile. The sensor system also includes at least one position sensor and at least one phase sensor. The sensor system further includes at least one digital interface and at least one incremental interface, the sensor system being configured to output at least one absolute position signal generated with the aid of the position sensor via the digital interface and to output at least one incremental signal generated with the aid of the phase sensor via the incremental interface.

Numerous conventional sensors can detect at least one rotation characteristic of rotating elements. A rotation characteristic is generally understood to be a characteristic which at least partially describes the rotation of the rotating element. It may be, for example, an angular velocity, a rotational speed, an angular acceleration, a rotation angle or another characteristic which may characterize a continuous or discontinuous, uniform or non-uniform rotation or turning of the rotating element. Examples of sensors of this type are described in Konrad Reif (publisher): "Sensoren im Kraftfahrzeug" (Sensors in Motor Vehicles), 2nd edition, 2012, pp. 63 through 74 and 120 through 129.
For example, a rotational speed of a rotor or an angular position of a rotor of an electric machine, in particular an electric machine of an electric vehicle, may be determined. Furthermore, a position of a camshaft of an internal combustion engine relative to a crankshaft including a so-called phase sensor, may be determined with the aid of a Hall sensor. A sensor wheel is typically mounted on the rotating axis. Teeth may be situated on the sensor wheel, which are scanned by the Hall sensor when the camshaft rotates.
Thus, a device for detecting a rotating part of an internal combustion engine is described in German Patent No. DE 40 11 503 A1, in which the rotating part is a sensor wheel disk provided with a large number of regular teeth. A sensor arrangement for the contactless detection of rotation angles at a rotating component is furthermore described in German Patent Application DE 10 2014 220 458 A1, the rotating component being coupled with a disk-shaped target. An electric machine is further described in German Patent Application DE 10 2013 203 937 A1, which includes a rotor, which is rotatably supported around a rotation axis in a stator, at least one optical sensor being provided, which is supported in a stationary manner with respect to the stator and which has an optical detection area. The rotor includes a marking device, which has at least one optical marking.
Despite the improvements brought about by sensor devices of this type, improvement potential still exists. Sensor devices of the type described thus often require a great deal of installation space. In the case of a defect, replacement is generally possible only with considerable complexity. In addition, a high degree of circuit complexity frequently exists. Moreover, a contouring error and a lack of accuracy frequently associated therewith generally play a great role, for example in measuring the rotation angle, in particular at high rotational speeds.

Sensor system for determining at least one rotation characteristic of an element rotating around at least one rotation axis


A system for producing a public ring that is fully homomorphically encrypted. The system comprises a processor which generates a first presentation G of a ring, where G=x,y|x2=0,y2=0,xy+(p+1)yx=1, where x and y are generators and p is a first private prime number. The system further generates a second presentation H of the ring. H is defined as follows: H=x,y,t|x2=0,y2=0,t=m1yx,xy+m2yx+t=1. In addition, m1 and m2 are positive integers and p+1=m1+m2, wherein t is a generator and the first presentation G and the second presentation H are isomorphic. The system further produces a public ring Ĥ that is fully homomorphically encrypted, where:

Homomorphic encryption (HE) is a type of encryption that permits various operations to be performed on encrypted data. A characteristic of homomorphic is that the output of the mathematical functions on the encrypted data, after being decrypted, matches the output of mathematical function performed on the underlying unencrypted data.
Homomorphic encryption enables performing arithmetic operations on encrypted data without knowledge of any secret decryption key. Most HE schemes to date have followed Gentry's or similar encryption schemes, but these schemes, that can generally evaluate low-depth circuits, remain inefficient due to required bootstrapping.
A fully homomorphic encryption scheme generally allows the computation of arbitrary functions over encrypted data without requiring the use of a decryption key. Homomorphic encryption is desired in a wide variety of fields that use cryptology. However, one drawback, is that homomorphic encryption and decryption algorithms tend to be processor-intensive and inefficient.
The most widely known existing solution to the fully homomorphic encryption problem is attributable to Craig Gentry with relevant software currently under development by IBM. This solution relies in its security on variants of the bounded-distance decoding problem that has the property of random self-reducibility. While this property has been shown to provide good evidence of security, the resulting homomorphic encryption algorithm is too inefficient to be practical in its application.
Accordingly, this solution is too inefficient to be practical. As a point of comparison and to further illustrate the point, Gentry's algorithm takes about 1800 seconds to encrypt a database with 106 entries, whereas the disclosed algorithm takes about 5 seconds (non-optimized). The disclosed algorithm is useful for doing private searches on an encrypted database as well as private information retrieval.
By way of background, ciphertext is also known as encrypted or encoded information because it contains a form of the original plaintext that is unreadable by a human or computer without the proper cipher to decrypt it. Ciphertex is the result of encryption performed on plaintext using an algorithm, called a cipher. A homomorphism is a structure preserving map between two algebraic structures (such as groups, rings or vector spaces) and is used in enabling computations on encrypted data. Homomorphic encryption is a form of encryption that allows computations to be carried out on ciphertext, thus generating an encrypted result which, when decrypted, matches the result of operations performed on the plaintext.
Homomorphic encryption is considered a desirable feature in modern communication system architectures. Homomorphic encryption permits the chaining together of different services without exposing the data to each of those services. A cryptosystem that supports arbitrary computation on ciphertexts is known as fully homomorphic encryption (FHE) and is considered more powerful than homomorphic encryption. Such a scheme enables the construction of programs for any desirable functionality, which can be run on encrypted inputs to produce an encryption of the result. Since such a program need never decrypt its inputs, it can be run by an untrusted party without revealing its inputs and internal state. Therefore, the existence of an efficient and fully homomorphic cryptosystem would have great practical implications in the outsourcing of private computations, for instance, in the context of cloud computing.
In order to provide semantic security, encryption has to be randomized but, on the other hand, a homomorphism should map zero to zero. In order to resolve this conflict, the ciphertext zero is "masked" by "noise". However, during any computation on encrypted data, this "noise" tends to accumulate and has to be occasionally reduced by recryption (a process also known as "bootstrapping") that produces the equivalent ciphertext but, with less noise. Even further, recryption is an expensive procedure and in effect, limits real-life applications of existing FHE solutions such as the solution proposed by Gentry.
There were other proposed solutions for fully homomorphic encryption following Gentry's such as methods disclosed by Z. Brakerski and V. Vaikuntanathan, Efficient fully homomorphic encryption from (standard) LWE, In: FOCS 2011, 97-106, IEEE Computer Soc., Los Alamitos, Calif., 2011; M. van Dijk, C. Gentry, S. Halevi, and V. Vaikuntanathan, Fully homomorphic encryption over the integers, In: Advances in Cryptology—EUROCRYPT 2010, Lecture Notes Comput. Sci. 6110 (2010), 24-43; or L. Ducas and D. Micciancio, FHE Bootstrapping in less than a second, preprint, http://eprint.iacr.org/2014/816. However, each of these methods generally implement bootstrapping techniques and thus, are also considered inefficient for similar reasons described in connection with Gentry's proposed solution.
An improved homomorphic encryption algorithm with increased efficiency on computation of encrypted data is therefore desired.
It is further desirable to implement a new practical private-key fully homomorphic encryption scheme based on homomorphisms between rings. Such FHE scheme would be implemented in conducting private search and private information retrieval on an encrypted database as well as for delegating computations on private data to a remote server, such as a cloud.
It is further desirable to implement a system and method using an FHE scheme that is unconditionally (i.e., without any computational assumptions) secure against ciphertext-only attack.
It is further desirable to provide a system and method with practical instantiation of an FHE scheme whereby resultant computation on encrypted data is accomplished without accumulating noise and is in orders of magnitude more efficient than currently available implementations.
It is yet further desirable to provide a system and method that implements unconditional ciphertext security for encryption of nonzero elements, even if the public is able to recognize encryptions of zero (0). This system and method achieves a very efficient private search on encrypted database without sacrificing any privacy of the data.
It is yet further desirable to provide a system and method that is private-key. Such a FHE private-key environment provides flexibility in terms of how much information the data owner is willing to give to the entity that stores (and operates on) any such encrypted data. In particular, this can provide a customer (including a company that holds sensitive data) with a "toolbox" for building their own instantiation of a general FHE scheme, so that any third party systems outside of the company would not have access to details of the encryption/decryption mechanisms, even though the public may be able to access and operate on encrypted data. This system and method would render "security through obscurity" impossible for FHE schemes, so while there should be some minimum amount of information available to the public, this minimum is essentially just the general framework.

System and method for private-key fully homomorphic encryption and private search between rings

Abstract: H      ^        =          〈              x        ,        y        ,                              t            ❘                          N              ·              1                                =          1                ,                              x            2                    =          1                ,                              y            2                    =          0                ,                  xyx          =          x                ,                  yxy          =          y                ,                  tx          =          0                ,                  yt          =          0                ,                              t            2                    =                      t            +                                                                                m                    2                    2                                    -                                      m                    2                                                                    m                  1                                                          tyx                                          〉        ,N=pq and further, q is a second private prime number, and the public ring Ĥ is further, publically available. A corresponding method is also disclosed.

Research Foundation of the City University of New York


A liquid repellant, stain-resistant, antimicrobial fabric. At least one composition comprising an antimicrobial agent and a fluorochemical composition is applied to a fabric such as a jacquard, to produce a treated fabric. The liquid and stain-resistant, antimicrobial, fabric essentially retains its natural texture, is durable and is easy to handle.

Stain resistance, water repellency and resistance to microbial growth are important in many uses of textile materials. In restaurants, for example, table cloths and seating upholstery often lack stain resistance and are subject to rapid water penetration. These properties necessitate frequent cleaning and/or replacement of such items. Although one generally views microbial growth as associated with fibers of biologic origin such as cotton, wool, linen and silk, in the field of marine use, the high relative humidity renders even synthetic polymer textiles, such as polyesters and polyamides, subject to microbial growth, which is also true of many other outdoor uses.
The term "water repellant" as used herein means essentially impermeable to water, i.e. treated textile can support a considerable column of water without water penetration through the fabric. Such behavior is sometimes termed "water resistant." However, the last term generally implies a lesser degree of water repellency and further can be confused with the chemical use of "water resistant" to refer to coatings which are chemically stable to water or which will not be washed off by water. Hydrophobicizing topical treatments are incapable of providing the necessary degree of water repellency as that term is used herein.
Textile fabrics may be made water repellant by various processes. For example, textile fabrics may first be scoured with a soap solution and then treated with a composition which may include zinc and calcium stearates as well as sodium soaps. The long chain carboxylic acid hydrophobic compounds provide a limited amount of water repellency. It is also possible to render fabrics liquid resistant by treating the fabric with commercially available silicone, for example poly(dimethylsiloxane).
To overcome problems associated with water absorption and stain resistance, resort has been made to synthetic leathers and polyvinylchloride (vinyl) coated fabrics. However, these fabrics do not have the hand or feel of cloth. Moreover, although attempts have been made to render such materials water vapor permeable, these attempts have met with only very limited success, as evidenced by the failure of synthetic leather to displace real leather in high quality seating and footwear.
Applications of relatively small amounts of fluorochemicals such as the well known SCOTCHGUARD.TM. and similar compounds also may confer a limited degree of both water repellency and stain resistance. However, for optimal water repellency, it has proven necessary to coat fabrics with thick polymeric coatings which completely destroy the hand and feel of the fabric. Examples include vinyl boat covers, where the fabric backing is rendered water resistant by application of considerable quantities of polyvinylchloride latex or the thermoforming of a polyvinyl film onto the fabric. The fabric no longer has the hand and feel of untreated fabric, but is plastic-like. Application of polyurethane films in the melt has also been practiced, with similar results. However, unless aliphatic isocyanate-based polyurethanes are utilized, the coated fabric will rapidly weather.
It would be desirable to provide a fabric that allows water vapor to pass through the fabric while prohibiting the passage of liquid. It would also be desirable to provide a method of producing a liquid repellant, stain resistant, antimicrobial fabric. It would further be desirable to provide a liquid repellant, stain resistant, antimicrobial fabric that retains its natural hand and texture, is easy to handle, and economical to produce.


Parastomal hernia support devices are disclosed herein. A parastomal hernia support device configured in accordance with embodiments of the present technology can include, for example, a support assembly including a generally rigid outer portion and a generally flexible inner portion having an aperture configured to be aligned with a stoma of the user. In some embodiments, the support assembly includes a tensioning assembly that can be actuated by the user to adjust the tension in a non-elastic strap that secures the support assembly against the user. For example, the user can increase the tension in the strap to add support to the peristomal tissues proximate the stoma to reduce the likelihood of the user developing a parastomal hernia.

An intestinal stoma is a surgically-created opening in the abdomen through which a portion of the intestine is brought to allow waste to exit from the intestines into, for example, a bag. Stoma formation surgery (e.g., a colostomy) is the surgical procedure in which the stoma is formed by drawing a portion of the intestine (e.g., a healthy portion) through an incision in the abdominal wall and suturing it into place. Patients require the formation of stomas as a result of many intestinal disorders, including inflammatory bowel disease and cancer (e.g., colon, rectal, or bladder). As of 2016, 1.2 million Americans are living with stomas, and this population is growing by 3% every year.
For patients who have undergone stoma formation surgery, enlargement of the abdominal wall opening through which the bowel exits (i.e., a "parastomal" hernia) is a common and potentially risky development, occurring in up to 78% of individuals having undergone a colostomy. Parastomal hernias develop due to weakness in the abdominal wall that is a result of disrupting the normal muscular support layers of the abdomen, then made worse by activities that increase abdominal strain (e.g., sneezing, bending over, picking up heavy objects, etc.). Other risk factors for developing a parastomal hernia include loop stomas (small and large bowel), obesity, malnutrition, and other metabolic/physiological conditions predisposing a patient to poor wound healing or increased intraabdominal pressure.
Parastomal hernias put the bowel at risk for twisting and obstruction and make management of the stoma more difficult due to increased leakage and skin ulceration under external stoma appliances. Surgical repair—including moving the stoma to another location in the abdomen and repairing the hernia site and/or implanting a reinforcing prosthetic mesh internally on the abdominal wall around the stoma—are costly, complex, and even with repair, there is a high recurrence rate. Furthermore, surgical repair is often not a safe option for medically-fragile patients. Prophylactic measures to reduce the likelihood of parastomal hernia development at the time of an initial surgical procedure add some risk and complexity and duration to what are already long anesthesia cases. Accordingly, there is a need in the art for improved methods of treating and preventing parastomal herniation.


A heating, ventilation, and air-conditioning (HVAC) assembly for supplying different mixed air flows simultaneously is disclosed. The assembly includes first blend kinematics configured for allowing passage of a first air flow, second blend kinematics configured for allowing passage of a second air flow, obtaining means configured to obtain a temperature command indicating a target temperature for two different locations outside the HVAC assembly, identifying means configured to identify a pattern for the first blend kinematics and the second blend kinematics for modifying the first air flow and the second air flow based on the temperature command, and coordinating means configured to coordinate each of the first blend kinematics and the second blend kinematics simultaneously.

In the automotive field, heating, ventilation, and/or air conditioning (HVAC) systems regulate the aerothermal parameters of the air circulated inside a motor vehicle. Air inlets are devices performing the functionality of allowing air flows from one area to another. The air inlets are doors that open and/or close following a user's command. As such, the air inlets allow air flow to travel from one chamber to another in an HVAC assembly when an air inlet.

Heating, ventilation, and air conditioning (HVAC) assembly for supplying different mixed air flows simultaneously and method for managing the same


A system for very-long-distance transmission of a digital signal between a transmitter station and a receiver station, wherein the transmitter and receiver stations are connected by a monomode optical fiber with negative chromatic dispersion at the operating wavelength of the system, having a length of at least one thousand kilometers. The receiver station comprises device to compensate for the distortions due to the non-linear effects and to the chromatic dispersion introduced by the transmission line, the compensation device carrying out a positive chromatic dispersion of the received signal, the amplitude of the positive chromatic dispersion being a function notably of the amplitude of the negative chromatic dispersion induced by the optical fiber as well as of the mean on-line optical power of the signal transmitted on the optical fiber.

1. Field of the Invention
The field of the invention is that of very-long-distance digital transmission (several thousands of kilometers) by optical fiber in systems using on-line optical amplification
One of the main factors limiting the bit rate in very-long-distance systems such as these is the distortion induced by the transmission fiber.
For, while these distortions may be more or less overlooked in standard fiber-optic systems (setting up links over distances in the range of some humdreds of kilometers), they have, on the contrary, very disturbing effects on long-distance transmission systems.
The invention relates to a system of transmission on an optic fiber line enabling compensation, at reception, for this distortion induced by the transmission line, in the case of transmission lines having a length of at least a thousand kilometers, such as those used for trans-ocean links.
The distortion contributed by the transmission fiber arises out of the combined existence of two phenomena that occur in the monomode fibers: chromatic dispersion and non-linear effects.
The first phenomenon is that of chromatic dispersion. This phenomenon results from the frequency dependency of the refractive index of silica. It entails different propagation times depending on the operating wavelength. In general, chromatic dispersion tends to widen the pulses of the digital trains and, hence, to create inter-symbol interferences.
In the commonly-used fibers, the chromatic dispersion is zero around 1.3 .mu.m and takes a positive value of about 17 ps/nm/km around 1.55 .mu.m. It is also possible to use dispersion-shifted fibers which are designed to have zero chromatic dispersion in the region of 1.55 .mu.m.
Very-long-distance transmission systems (covering several thousands of kilometers) work at 1.55 .mu.m. The excessive value of the chromatic dispersion of the commonly used fibers at this wavelength rules out their use. Hence, dispersion-shifted fibers will be used in these cases.
It must be noted that the effect of distortion by chromatic dispersion depends greatly on the spectral components of the pulses: if a pulse shows variations in optical phase that are positive at its start and negative at its end, it will be greatly widened by a positive chromatic dispersion. The converse is true for negative dispersions.
The second phenomenon relates to the non-linear effects. The most important non-linear effect in a fiber is the Kerr effect. This effect, which is described for example in the document by K. W. Blow and N. J. Doran, "Non-linear Effects in Optical Fibers and Fiber Devices" (IEEE Proceedings, June 1987, pp. 138-144) reflects a linear dependency of the refractive index of silica with respect to the optical power.
The non-linear effect is very low in the usual fields of operation of the optical systems (distance smaller than 400 km and power below about 10 mW), but becomes non-negligible for very high power values (of the order of 1 W) or for very large propagation distances at reasonable levels of power (some thousands of kilometers in a periodic amplification system).
When there is no chromatic dispersion, the Kerr effect induces a self-phase modulation of the optical pulse: the instantaneous frequency diminishes at the start of the pulse and then increases at its end, proportionally to the derivative of the optical power. This induces a widening of the spectrum and a spectral composition that fosters a substantial widening for negative chromatic dispersions.
The distortion provided by the transmission fiber should be considered as the combination of the chromatic dispersion (the first phenomenon) and of the non-linear effects (the second phenomenon).
The combination of these two effects may be described by a non-linear equation with partial derivatives of distance and time, known as Schrodinger's non-linear equation, the resolving of which is discussed notably in the work by G. Agrawal, "Non-Linear Fiber Optics", Academic Press.
The numerical resolution of this equation shows that there are two forms of behavior which are qualitatively very different depending on the sign of the chromatic dispersion (D):
* First case: D>0. In this case, phenomena of instability of modulation are observed. The pulses "burst" into very short pulses at the end of 1000 to 2000 km and the optical spectrum widens considerably: this may give rise to problems related to the optical passband. PA1 * Second case: D<0. There is no instability of modulation and the pulses keep a certain degree of integrity while the spectrum widens quasi-monotonically during the propagation, while keeping reasonable widths. However, the pulses widen greatly temporally, thus creating inter-symbol interferences. These interferences become very troublesome for example, as soon as the chromatic dispersion goes beyond 0.05 ps/nm/km in terms of absolute value for bit rates of 5 Gbits/s on distances of 6000 to 8000 km.
The most efficient case is naturally the second one, that of a negative chromatic dispersion. However, to make the very-long-distance systems work in negative dispersion mode, the values of chromatic dispersion of the fibers used must obligatorily be very low.
2. Description of the Prior Art
Any method of compensation for the two phenomena that are the cause of the distortion in the fiber (chromatic dispersion and non-linear effects) is therefore of great value since it can be used to overcome the drawback of the low values imposed on the chromatic dispersion. Indeed, by using a method of compensation for the distortion provided by the transmission fiber, it is possible to envisage two strategies.
In a first strategy, for given characteristics of negative chromatic dispersion of the transmission fiber, the compensation can be used to increase the product: line bit rate * range of the link.
In a second strategy, for a fixed line bit rate and a fixed range, the compensation makes it possible to use transmission line fibers having less stringent constraints as regards the characteristics of chromatic dispersion. These fibers are easier to manufacture on an industrial scale and to sort out for the setting up of an underwater link for example.
There are known methods of compensation for the distortion introduced by a fiber-optic transmission line.
A first known method, described for example by A. H. Gnauck et al in the article "Dispersion Penalty Reduction Using an Optical Modulator with Adjustable Chirp" OFC 1991, post-deadline paper No. 17, consists of the use, at transmission, of an optical amplitude modulator having adjustable chirp (or variation in instantaneous optical frequency).
This first method has been proposed solely in order to provide partial compensation for the penalties of chromatic dispersion on standard optical fibers in short-distance transmission systems (of some hundreds of kilometers).
Indeed, it has not been sought, in this method, to compensate for the non-linear effects, which are completely negligible in this case, but solely to compensate for chromatic dispersion.
Besides, this first known method specifically relates to standard optical fibers (with zero chromatic dispersion around 1.3 .mu.m). Now, in very-long-distance transmission systems (of several thousands of kilometers), the excessive value of the chromatic dispersion of the commonly used fibers rules out their use, and then it is generally dispersion-shifted fibers (namely fibers with zero chromatic dispersion around 1.55 .mu.m) that are used.
Finally, the compensation takes place at the transmitter station and hence by anticipation, and not at reception, on the actually disturbed signal.
It can therefore be clearly seen that this first known method is not suited to very-long-distance transmission systems and does not relate to a system of compensation for distortions at reception.
A second known method of compensation, described for example by T. Koyama et al. in the article, "Compensation for Non-Linear Pulse Distortion in Optical Fiber by Employing Prechirp Technique", ECOC 91., WeC7-2 p. 469, consists of compensation, at transmission, for the self-phase modulation generated by the non-linear effects.
To this end, the pulses are made to undergo a continuous scanning of the optical frequency, for the duration of a bit, by over-modulation of the sending laser.
What is used in this case is the fact that the optical frequency of a semiconductor laser is a function of its current. However, only certain structures of lasers can thus display high efficiency of frequency modulation, i.e. a major variation of this optical frequency, for a small variation of the control current and hence of the optical power.
This second known method has the drawback of requiring a particular over-modulation, which is synchronous with the useful digital train, on the sending laser used. Consequently, only certain types of lasers, those capable of providing a major variation of the optical frequency for a low variation of the control current, may be used in this second method.
Furthermore, this method can be applied only for a particular binary coding, namely the on-line RZ coding.
Furthermore, just as in the first method described, the compensation takes place at transmission and not at reception.
Finally, this method enables compensation solely for non-linear effects.
There are other known methods of compensation that work for the correction, at reception, of the distortion due to the combination of high positive chromatic dispersions and non-linear effects (in particular the chirp of the laser, this "chirp" of the laser being a parasitic effect that consists of a variation of the instantaneous optical frequency, during a pulse, especially at the beginning and end of this pulse).
These other methods use different structures (a Fabry-Perot filter for example) which have the drawback of correcting the distortions only very partially.
In particular, the non-linear effects are not compensated for by these known equalizers or filters. Now, the change from a transmission line with a length of some hundreds of kilometers to a line with a length of over a thousand kilometers leads to a situation where it is not longer possible to overlook the non-linear effects.
Indeed, these non-linear effects become as important, if not more important, than chromatic dispersion. Consequently, a specific solution has to be found in order to resolve this new problem.
The invention is aimed notably at overcoming these different drawbacks of the prior art.
More specifically, it is an aim of the invention to provide a system capable of compensating for the distortion induced by a transmission line with a length of at least a thousand kilometers on a monomode optical fiber with negative chromatic dispersion.
Another aim of the invention is to provide a system such as this providing compensation for the combination of the two phenomena induced by the transmission fiber, namely the negative chromatic dispersion and the non-linear effects, and not solely for either one of these phenomena.
The invention is also aimed at providing a system such as this, capable of being implemented irrespectively of the type of laser used at transmission.
Another aim of the invention is to provide a system such as this that is simple to implement and reliable and that costs little.

System of very-long-distance digital transmission by optical fiber with compensation for distortions at reception


A method of assembling an optical fiber cable on production casing includes positioning the optical fiber cable against a production casing at a hole of a well site, and affixing the optical fiber cable against the production casing by applying an adhesive to the production casing to secure the optical fiber cable against the production casing. The method further includes applying pressure to the adhesive to adhesively bond the optical fiber cable to the production casing along a length of the production casing while the production casing is being run-in-hole.

Sensing cables can be positioned downhole to monitor conditions in a wellbore, including for example temperature, pressure, and acoustics. The sensing cables can be coupled to a casing string or other tubing string and positioned downhole to monitor the conditions in the wellbore. Knowledge regarding the position of the sensing cable can help to prevent damage to the cable during run-in-hole, cementing, and other downhole procedures, for example, but not limited to, perforating holes in a casing string. Sensing cables can be less likely to be damaged when their positions are known with greater accuracy.
Installing the sensing cables on production casing has traditionally been a labor intensive and hardware focused process, using clamps to secure the cables on the casing, and blast protectors and flatpacks to protect the cable, all of which are installed manually, e.g., by hand.

Method for installing fiber on production casing


Provided is a novel compound or a salt thereof inhibiting MTHFD2 and useful for treating a disease caused by overexpression of MTHFD2, a disease involved in overexpression of MTHFD2 and/or a disease associated with overexpression of MTHFD2.

MTHFD2 is one of the isoforms of MTHFD, which is an enzyme involved in folate metabolism, and present in mitochondria. MTHFD2 is a bifunctional enzyme catalyzing a NAD+ dependent methylene-tetrahydrofolate dehydrogenase reaction and a methenyltetrahydrofolate cyclohydrolase reaction. The NAD+ dependent methylene-tetrahydrofolate dehydrogenase reaction is a reaction using 5,10-methylenetetrahydrofolate as a substrate to produce 5,10-methenyltetrahydrofolate. The methenyltetrahydrofolate cyclohydrolase reaction is a reaction using 5,10-methenyltetrahydrofolate as a substrate to produce 10-formyltetrahydrofolate.
Recently, it was reported that MTHFD2 can serve as a potential target molecule for cancer treatment (Non Patent Literature 1). More specifically, it was reported that MTHFD2 expression is remarkably enhanced in various cancers both at a mRNA level and at a protein level; and that enhancement of MTHFD2 expression is correlated with poor prognosis of breast cancer. It was also reported that if expression of MTHFD2 in cancer cells is inhibited by RNA interference, growth of the cancer cells decreases and cell death occurs significantly. MTHFD2 expression is observed in a developing embryo and is scarcely found in tissues of healthy adults even though the tissues are growing. Because of this, agents inhibiting MTHFD2 are expected to be useful as anti-cancer agents with fewer adverse drug reactions.
As compounds inhibiting MTHFD2, several folic acid analogues are known so far (Non Patent Literatures 2, 3).

Sulfonamide derivative having coumarin skeleton

Abstract: Solution

Abstract: Provided is a sulfonamide derivative having a coumarin skeleton represented by the following formula (I) and having various substituents:

Abstract: wherein R1, R2, R3, R4, R5, R6 and R7 are the same as defined in the specification,and a salt thereof.


A keyswitch device of the invention includes a plurality levers (first to third levers), one side of each lever rotating engaging the base plate; a holder supported so as to be upwardly and downwardly movable with respect to the base by being engaged with the other side of each lever; and a switch, disposed between the base plate and the holder, for performing a switching operation as the keytop is moved upward and downward. Rotary shafts of the first and second levers symmetrically disposed on the left and right sides engage a groove of the holder. A rotary shaft of the third lever is disposed so as to cross the rotary shafts disposed at engagers at the first and second levers.

1. Field of the Invention
The present invention relates to a keyswitch device suitable for use in a keyboard device used as an input/output device of, for example, a word processor or a personal computer, and a keyboard device including the keyswitch device.
2. Description of the Related Art
Hereunder, a related X-shaped keyswitch device used in a keyboard device will be described with reference to FIGS. 4 and 5. A mount member 31 is formed of, for example, a metallic plate and comprises a bottom wall 31a, a plurality of relatively long supporting sections 31b, and a plurality of semi-circular arc shaped holding sections 31c. In order to form the supporting sections 31b, cuts are formed in the bottom wall 31a and the cut portions that are joined at two sides are raised. These cut-and-raised portions are disposed side by side and correspond to the supporting sections 31b. In order to form the holding sections 31c, cuts are formed in the bottom wall 31a in a cantilever manner and the cut portions that are joined at one side are raised. These cut-and-raised portions are disposed side by side and correspond to the holding sections 31c, each of which forms a pair with its associated supporting section 31b. A flexible substrate (not shown) having a plurality of stationary contacts is disposed on the top surface of the bottom wall 31a. A movable contact member 33 comprises a cup-shaped movable section 33a, formed of resin or the like, and a contact section 33b, disposed on the upper surface of the inner portion of the movable section 33a. The movable contact member 33, opposing stationary contacts 32, is mounted to the flexible substrate. When the movable section 33a is pushed and moved, the contact section 33b comes into contact with the stationary contacts 32, whereas, when the movable section 33a is released, the movable section 33a returns to its original state by itself, causing the contact section 33b to move out of contact with the stationary contacts 32. A first lever 34 is molded out of synthetic resin and has a U shape. It comprises a pair of arms 34a, a connecting section 34b connected to one end of each arm 34a, and a circular cylindrical engager 34c disposed at the other end of each arm 34a. A second lever 35 is molded out of synthetic resin and has an H shape. It comprises a pair of arms 35a, a connecting section 35b connected to the central portion of each arm 35a, and circular cylindrical engagers 35c and 35d disposed at respective ends of each arm 35a. By positioning the second lever 35 inside the first lever 34 and placing them so that their central portions are aligned, the first and second levers 34 and 35 are rotatably combined in the form of a cross by a rotary shaft 34d, so that the combined form of the first and second levers 34 and 35 has an X-shaped pantograph structure. With the rotary shaft 34d as a fulcrum, the upper sides of the first and second levers 34 and 35 can move vertically. The first and second levers 34 and 35 combined in this manner are mounted to the mount member 31 in the following way. First, as shown in FIG. 4, one end of one arm 35a and one end of the other arm 35a of the second lever 35 are pushed towards each other in the directions of arrows X. With these ends of the arms 35a moved towards each other, the engagers 35c are aligned with their respective holding sections 31c. When, after the alignment, the ends of the arms 35a that have been pushed towards each other in the directions of arrows X are released, the arms 35a return to their original states by themselves, causing the engagers 35c to be engaged inside the respective holding sections 31c. Next, as shown in FIG. 4, one end of one arm 34a and one end of the other arm 34a of the first lever 34 are pushed towards each other in the directions of arrows Y. With these ends of the arms 34a moved towards each other, the engagers 34c are aligned with the respective supporting sections 31b. When, after the alignment, the ends of the arms 34a that have been pushed towards each other in the directions of arrows Y are released, the arms 34a return to their original states by themselves, causing the engagers 34c to be engaged inside the respective supporting sections 31b. In this way, both the first and second levers 34 and 35 are mounted to the mount member 31 with the pairs of arms 34a and 35a in pushed states. When the first and second levers 34 and 35 are mounted to the mount member 31, the movable contact member 33 is positioned below the central portions of the crossing portions of the first and second levers 34 and 35, so that the movable contact member 33 can be pushed by the second lever 35. A keytop 36 is molded out of synthetic resin and has the shape of an inverted boat. It comprises guides 36a and 36b. The guide 36a is a vertical groove disposed at the inner portion of the lower surface of the keytop 36. The guide 36b is a horizontal groove disposed at the inner portion of the lower surface of the keytop 36. The keytop 36 is mounted to and supported by the first and second levers 34 and 35 by fitting the connecting section 34b of the first lever 34 to the guide 36a and fitting the engagers 35d of the second lever 35 to the guide 36b. The one keytop 36 having such a structure, the pair of first and second levers 34 and 35, the movable contact member 33, the stationary contacts 32, and the mount member 31 form one keyswitch device. By disposing a plurality of such keyswitch devices, a keyboard device is formed. Next, the operation of such a related keyswitch device will be given. First, when the top surface of the keytop 26 is pressed, the first and second levers 34 and 35 are pushed, so that, with the rotary shaft 34d as a fulcrum, the first and second levers 34 and 35 are rotated and moved downward. At this time, the engagers 35c of the second lever 35 are rotated while they are held by their respective holding sections 31c, and the engagers 34c of the first lever 34 are slid horizontally while they are supported by their respective supporting sections 31b. At the keytop 36, the engagers 35d of the second lever 35 are slid horizontally inside the guide 36b, and the connecting section 34b of the first lever 34 is slid vertically inside the guide 36a.
By the downward movement of the first and second levers 34 and 35, the movable section 33a of the movable contact member 33 is pushed downward, causing the contact section 33b to come into contact with the stationary contacts 32, so that the keyswitch device is turned on. Next, when the keytop 36 is released, the movable section 33a returns to its original state, causing the first and second levers 34 and 35 to be pushed back upward. This causes the keytop 36 to move upward, so that the first and second levers 34 and 35 and the keytop 36 return to their original states before being pushed, so that the keyswitch device is turned off.
The keyswitch device having the above-described structure is widely used in, for example, keyboard devices of personal computers. However, size reduction of electronic devices in recent years has resulted in an increased tendency for a demand for smaller and thinner keyswitch devices. However, in the keyswitch device having the structure shown in FIGS. 4 and 5, the rotary shaft 34d serving as the center of rotation of the levers 34 and 35 is at the centers in the lengthwise direction of the levers 34 and 35, the keytop 36 is connected to the top sides of the levers 34 and 35 with the rotary shaft 34d as the center, and the bottom sides of the levers 34 and 35 are connected to the mount member 31, so that, as the levers 34 and 35 are shortened for the purpose of forming a smaller and thinner keyswitch device, a limit in the lengths of the levers 34 and 35 that allow smooth rotation is reached, so that further reduction in size and thickness cannot be achieved. In addition, in the keyswitch device having their levers disposed in the form of an X shape as viewed from a side, when a top peripheral edge of the top surface at a bearing side of the keytop 36 is pressed, the keytop 36 may tilt in directions A and B in FIG. 5, in which case it is pressed without being moved horizontally downward. In such a case, the contact section 33b may not come into contact with the stationary contacts 32 even if the keytop is pressed. Therefore, there is a demand for a keyswitch device which makes it possible to perform a key input operation by reliably causing the contact section to come into contact with the stationary contacts even when a peripheral edge of the top surface of the keytop is pressed by, for example, a finger.
The present invention has been achieved to overcome the aforementioned problems, and has as its object the provision of a keyswitch device which makes it possible to perform a key input operation by reliably causing a contact section to come into contact with a stationary contact even when a peripheral edge of the top surface of a keytop is pressed by, for example, a finger. It is another object of the present invention to provide a keyboard device which comprises the keyswitch device, which can be easily reduced in size, and which can be easily operated.
To these ends, according to one aspect of the present invention, there is provided a keyswitch device comprising a base; a plurality of levers, one side of each lever movably engaging the base; a keytop supported so as to be movable vertically with respect to the base by being engaged with the other side of each lever; and a switch for performing a switching operation when the keytop is moved vertically. In the keyswitch device, rotary shafts for allowing rotation of the respective levers within respective rotational planes are disposed at respective engagers at both sides of the levers. One of the engagers at each lever is a first engager for movably supporting one of the rotary shafts at the base or the keytop. The other engager at each lever is a second engager for rotatably supporting the other rotary shaft. The plurality of levers comprise a first lever, a second lever, and a third lever. The rotary shafts or rotary shaft lines of the first and second levers cross the rotary shafts of the third lever. The engagers at the keytop side at the first and second levers are the first engagers for movably engaging the rotary shafts of the first and second levers in a guide groove in the keytop.
In other words, unlike the related keyswitch device in which two levers are such that a shaft is fixed at the location where they cross, the levers independently engage the base and the keytop, and the rotary shafts of at least one lever are disposed so as to cross the rotary shafts of another lever. By virtue of such a structure, even if the lengths of the levers are reduced for reducing the size and thickness of the keyswitch device, the operability of the keyswitch device at the time of a key input operation is not impaired, and the keyswitch device can be more easily reduced in size and thickness than the related keyswitch device having an X-shaped supporting structure.
When a peripheral edge of the top surface of the keytop is pressed at the time of a key input operation, the keytop is not moved downward in a tilted state, but is moved downward in a substantially horizontal state. For example, if the case of supporting the keytop by two levers is considered, when, as in the related keyswitch device, the rotary shafts at the keytop side of these levers are disposed parallel to each other, the keytop can tilt in a direction perpendicular to these rotary shafts. However, in the structure of the present invention, tilting of the rotary shafts of one of the levers in the direction of rotation of the rotary shafts is restricted by the other lever whose rotary shafts cross these rotary shafts, so that the keytop is moved vertically in a horizontal state. Therefore, according to the keyswitch device of the present invention, rattling of the keytop in the horizontal direction can be prevented from occurring, and the keytop is moved vertically without being tiled, so that the switch can reliably perform a switching operation at the time of a key input operation.
Another structure may be used for the keyswitch device. Here, the keyswitch device comprises a base; a plurality of levers, one side of each lever movably engaging the base; a keytop supported so as to be movable vertically with respect to the base by being engaged with the other side of each lever; and a switch for performing a switching operation as the keytop is moved vertically. In the keyswitch device, rotary shafts for allowing rotation of the respective levers within respective rotational planes are disposed at respective engagers at both sides of the levers. One of the engagers at each lever is a first engager for movably supporting one of the rotary shafts at the base or the keytop. The other engager at each lever is a second engager for rotatably supporting the other rotary shaft. The plurality of levers comprise a first lever, a second lever, and a third lever. The rotary shafts or rotary shaft lines of the first and second levers cross the rotary shafts of the third lever. The engagers at the keytop side at the first and second levers are the second engagers for rotatably engaging the rotary shafts of the first and second levers in a guide groove in the keytop. Even with this structure, advantages similar to those of the keyswitch device of the one aspect are provided.
In a first form, the plurality of lever members each comprise a pair of arms and at least one connecting section connecting the arms, and each have a U shape or a frame shape in plan view, and the rotary shafts are disposed at respective sides of the arms. According to this structure, the switch can be surrounded by the levers without reducing the supporting strength of the key top by the levers.
In a second form, when the structure of the one aspect is used, the rotary shaft at the keytop side of the third lever is disposed below the rotary shafts at the keytop side of the first and second levers. According to this structure, by disposing the third lever whose rotary shafts cross the rotary shafts of the first and second levers below the first and second levers, space below the keytop can be effectively used, so that the keyswitch device can be easily reduced in thickness and size.
In a third form, when the structure of the first form is used, the first and second levers are each sandwiched at a pair of hook-shaped rotary bearings disposed at the base engaging the first and second levers, and the positions of the first and second levers in the lengthwise directions of the rotary shafts of the first and second levers are restricted by the respective pairs of hook-shaped rotary bearings. According to this structure, movements of the first and second levers in the directions of the rotary shafts are restricted, so that rattling of the keytop can be effectively restricted.
In a fourth form, when the structure of the first form is used, the third lever is sandwiched at and engaged with a pair of hook-shaped slide bearings disposed at the base, and the position of the third lever in the lengthwise direction of the rotary shaft is restricted by the hook-shaped slide bearings. According to this structure, movement of even the third lever in the directions of the rotary shafts can be restricted, so that rattling of the keytop can be further restricted.
In a fifth form, when the structure of the first form is used, the keytop and the third lever are engaged by engagement of a rotary bearing of the keytop and the shaft of the third lever, and the position of the rotary bearing is restricted by being sandwiched by the pair of arms of the third lever. According to this structure, the positions of the keytop and the third lever are restricted, so that rattling of the keytop can be more effectively restricted.
In a sixth form, when the structure of the one aspect is used, the keytop comprises a holder engaging each lever and a key cap adhered to the holder. By virtue of such a structure, since the structural members, including the holder, the levers, and the base, can be used as common members regardless of the type of key cap, a keyswitch device which has a wide range of application and which can allow easy replacement of, for example, the key cap can be provided.
In a seventh form, when the structure of the sixth form is used, the shafts at the keytop side of the first and second levers are sandwiched by a recessed portion of the holding member, where the guide groove for movably supporting the shafts is disposed, and the key cap adhered to the holder. By virtue of such a structure, the first and second levers can be easily engaged with the keytop, so that the keyswitch device can be easily assembled. Since the rotary shafts of the first and second levers are sandwiched by the key cap and the holder, the rotary shafts and the key cap are always kept parallel, so that tilting of the key cap occurs even less frequently.
According to another aspect of the present invention, there is provided a keyboard device comprising any one of the above-described keyswitch devices. The keyboard device comprising the keyswitch device of the present invention can be easily reduced in size and thickness and is such that the keytop of the keyswitch device can be moved vertically in a constantly horizontal state. Therefore, when the keyswitch device is pressed, a key input operation can be reliably performed, so that a keyboard having excellent operability can be provided.


A cardio-pulmonary compression system includes a compression device (110), a supporting mechanism (120) coupled to the compression device and a feedback sensor (104) configured to measure interactions between a patient and the compression device. A control unit (112) is configured to receive input from the feedback sensor and adjust operating parameters of the compression system to meet a target parameter during operation of the compression device.

Technical Field
This disclosure relates to cardiopulmonary instruments and more particularly to methods and devices for automatic cardiopulmonary resuscitation (CPR) systems.
Description of the Related Art
Mechanical cardiopulmonary resuscitation (CPR) devices have switched from pneumatic devices to electro-mechanically powered compression mechanisms. These devices use battery powered motors and provide precise control and adjustability of compression rate and depth. The American Heart Association (AHA) and the European Resuscitation Council (ERC) have each established best-practice guidelines for cardiopulmonary resuscitation. A key variable specified by both is the depth of compressions. To reach the specified depth of chest compression, a significant amount of force is required. In addition, the amount of force required to reach the specified depth varies from patient to patient.
Mechanical CPR devices currently on the market may be divided into two configurations. These include rigid structure devices and chest-mounted devices.
For rigid structure devices, the chest compression mechanism or "chest compressor" is suspended above the patient using a rigid frame or structure, with a rigid backboard underneath the patient. These devices usually have some means of height adjustment to accommodate patients of different sizes. In rigid structure devices, although the chest compressor's stroke distance with respect to the chest compressor's housing can be tightly controlled by the drive mechanism's control system, the actual compression depth applied to the patient can be substantially less than the therapy depth range specified in the AHA and ERC guidelines. A significant portion of this error in patient compression depth can be attributable to the mechanical deflection of the support structure and backboard, due to the high compression forces required for adequate perfusion. This inadequate compression depth may result in adverse patient outcomes.
For chest-mounted devices, the chest compression mechanism or "chest compressor" is directly supported by and rests atop the patient's chest, and flexible straps and/or belts (hereafter "straps") are used to affix the compression device to the patient. These devices may or may not utilize a rigid backboard underneath the patient. In chest-mounted devices, although the chest compressor's stroke distance with respect to the chest compressor's housing can be tightly controlled by the drive mechanism's control system, there are a number of reasons why the chest compressor may lift up off the patient's chest. When this happens, the actual compression depth received by the patient can be substantially less than the intended compression depth. Inadequate compression depth may result in adverse patient outcomes.
There are a number of potential sources of lift-off. It is up to the caregiver to sufficiently tighten the straps to ensure that the chest compressor is properly secured. If not done correctly, this could result in chest compressor lift-off. The chest compressor may also lift up off the patient's chest due to physiological changes in the patient's chest during therapy, including, but not limited to a change in the cross-sectional shape (e.g., "chest molding" or "compression set") and/or changes in the relative stiffness of the chest. In addition, while the compressor's stroke may be the primary source of these changes, the straps themselves, due their shape, position, and tension, may also contribute to this effect. In these scenarios, while the straps and chest compressor may have been secure at the start of therapy, they may begin to loosen, and the chest compressor may begin to lift off the chest as compression therapy progresses. During compressions, the straps will carry a tensile load corresponding to the compression load applied to the patient. The tensile stiffness of the straps, a function of the straps' material and construction, will determine how much the straps stretch during compressions. This stretch will also contribute to the chest compressor lifting off the patient's chest.

Compensation for deflection in an automated cardiopulmonary compression device


In a picture encoding apparatus, block type determining means 22 judges whether a frame rate is lower than a threshold value A, and compares a block moving amount with a threshold value B when the frame rate is lower than the threshold value A. If the block moving amount is larger than the threshold value B, the current block is determined as a block to be compressed in a high picture-quality mode. Further, the differential value between the current block and a reference block is calculated, and the value of the high frequency component of the differential block is compared with a threshold value C. If it is larger than the threshold value C, the block is judged as a block to be compressed in the high picture-quality mode. Data amount assignment means 23 generates a quantization scale factor to assign a data amount to each block in accordance with the block type determined by the block type determining means 22, and then supplies the quantization scale factor to quantizing means 24.

1. Field of the Invention
The present invention relates to a picture encoding apparatus and more particularly, to a picture encoding apparatus for compressing video signals on a real-time basis.
2. Description of the Prior Art
When pictures/voices are transmitted/received by using a telephone line or a digital line as in the case of a videophone, a system in which data are compressed and transmitted in conformity with transmission performance of the line and the data thus transmitted are expanded at a reception side is generally used.
FIG. 9 is a block diagram showing a conventional picture compression apparatus.
In FIG. 9, a video signal of a subject which is picked up by camera 11 is supplied to picture input means 12 and then divided into plural blocks. A block having high correlation with reference picture data is searched every block by motion detection means 13, and the differential between the block thus searched and the current block is calculated. The differential data are converted to frequency components in conversion means 14, and then quantized in quantizer 15.
The quantized data outputted from quantizer 15 are inversely quantized in inverse quantizer 18, and then supplied to inverse conversion means 19 to be converted from the frequency components to pixel values. Thereafter, the differential data are restored to reference picture data in motion compensation means 20, and then supplied to motion search means 13. On the other hand, the quantized data are supplied to variable-length encoding means 16 to be subjected to variable-length encoding on the basis of run length or the like, and then transmitted to transmission path by transmission means 17.
In order to enhance the picture quality when the above picture compression processing is carried out under such a condition that the transmission performance of the line is restricted, there is known a method of increasing the data amount per one frame. However, if a large data amount is allocated to one frame, it takes a long time to complete the transmission of the frame, and thus a time interval until the data of a next frame are compressed is increased. As the time interval is increased, intermittent moving pictures are obtained (i.e., moving pictures obtained are as if some frames thereof are intermittently missed (hereinafter referred to as "frame-missed moving pictures").
On the other hand, if the data amount per one frame is reduced, the time interval until a next frame becomes shorter, and thus the motion becomes smoother. However, since the data amount per frame is small, block-shaped noises appear in pictures, resulting in degradation of picture quality.
Therefore, when the video data are transmitted through a line having low transmission performance, frame-missed moving pictures are transmitted or the picture quality is extremely degraded.
In order to avoid this phenomenon, it is required to improve the allocation of the data amount within one frame without increasing the data amount to be allocated to one frame and allocate a large data amount to portions to which viewers pay their attention.
Therefore, an apparatus which samples a picture of one frame and uses the correlation between adjacent pixels has been hitherto known as a picture encoding apparatus which enhances the picture compression efficiency as disclosed, for example, in JPA-8-242446. Further, there has been also known a picture encoding apparatus in which a still picture is sectioned into plural blocks and the fineness of gradation is adaptively varied every block to perform the optimum compression as disclosed, for example, in JPA-1-93278. Still further, there has been hitherto known a picture encoding apparatus in which the correlation between blocks is examined when a still picture is compressed and a high-correlation block are approximated by a preceding block as disclosed, for example, JPA-4-344771.
These conventional picture encoding apparatuses take no account of successive pictures or the enhancement in picture quality for the frame-missed moving pictures, and thus degradation of picture quality becomes remarkable when compressed pictures are intermittent. Further, in the conventional apparatus disclosed in JPA-8-242446, the data amount to be allocated to one frame is not taken into consideration, and a dedicated expanding apparatus must be provided to an expansion side.
In JPA-1-93278, there is no mention of the support of moving pictures, and also the data amount to be allocated to one frame is not taken into consideration. Further, in JPA-4-344771, a support of moving pictures is not taken into consideration, and also there is no mention of enhancement of picture quality.


An impeller pump has a pump casing (6) that defines a pump chamber. The pump chamber includes a first chamber (21) and a second chamber (22). An impeller (10) is rotatably disposed within the pump chamber. The impeller has a first groove group and a second groove group on opposite surfaces. The first groove group and the second groove group oppose to the first chamber and the second chamber, respectively, so that a fluid is draw into and discharged from the first and second chambers as the impeller rotates. The flows of the fluid discharged from the first and second chambers are converged at a converging channel (26). Pulsations of the fluid discharged from the fist and second chambers are canceled each other when the flows converge at the converging channel.

This application claims priorities to Japanese patent application serial numbers 2002-069149 and 2002-178991, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to impeller pumps of a type known as Westco pumps, generative or friction pumps, cascade pumps and circumferential-flow pumps that have rotary impellers. In particular, the present invention relates to impeller pumps that are suitably used as fuel pumps for vehicles, e.g. automobiles.
2. Description of the Related Art
Japanese Laid-Open Patent Publication No. 3-18688 teaches a know Westco pump that includes a pump casing and an impeller rotatably disposed within the pump casing. A plurality of grooves are formed in the outer periphery on each side of the impeller and are arranged in the circumferential direction. The pump casing defines a pump chamber that opposes to the grooves. An inlet port and an outlet port are defined in the pump casing and communicate with the pump channel.
In general, when low noise pumps are desired, Westco pumps are chosen due to their low noise properties in comparison with displacement-type pumps, e.g., gear pumps, vane pumps and trochoid pumps. When a pump is operated, a fluid with pulsation in pressure is discharged from the pump. As for Westco pumps, pulsation of a fluid discharged from Westco pumps may appear as a periodical-variation in flow rate (an alternative component or a variation component) that is superposed on a uniform flow rate (a linear component or a constant component). Therefore, Westco pumps may produce relatively low noises in comparison with displacement-type pumps as described above.
However, known Westco pumps still generate noises due to periodical variation in flow rate that may be caused by the nature of impellers that have vane grooves or vanes spaced from each other in the circumferential direction.
In addition, due to recent demands for low-noise automobiles, there has been a strong demand for low-noise impeller pumps that are used as fuel pumps for automobiles.
It is accordingly an object of the present invention to teach improved techniques for reducing or minimizing noises from impeller pumps.
According to one aspect of the present teachings, impeller pumps are taught that may have at least one pump chamber each including a first chamber and a second chamber. An impeller may be rotatably disposed within the pump chamber. The impeller may have a first groove group and a second groove group on opposite surfaces. The first groove group and the second groove group may oppose to the first chamber and the second chamber, respectively, so that a fluid is draw into and discharged from the first and second chambers as the impeller rotates. The flows of the fluid discharged from the pump chambers may have pulsations that are canceled each other when the flows of the fluid are converged at the converging channel.
Therefore, noises that may be produced due to pulsations of the fluid may be reduced or minimized.
According to another aspect of the present teachings, the pulsations of the fluid may be cancelled by determining the relative positions of the first groove group and the second groove group in the circumferential direction and/or the relative positions of outlets ports of the first and second chambers.
According to another aspect of the present teachings, the outlet ports of the first and second chambers may be positioned at the same position in the circumferential direction. On the other hand, the first groove group and the second groove group may be offset from each other by a distance that may correspond to a pitch of the grooves in the circumferential direction divided by the number of the groove groups. For example, if the pump includes a single pump chamber, the first groove group and the second groove group may be offset from each other by a distance that may correspond to half the pitch of the grooves. As a result, the phases of pulsations of the fluid from the first and second chambers may be shifted from each other by a cyclic period of the pulsations divided by the number of the groove groups. Therefore, the pulsations may be canceled when the flows of the fluid from the first and second chambers converged at the converging channel.
According to another aspect of the present teachings, the first groove group and the second groove group may be positioned at the same position in the circumferential direction. On the other hand, the outlet ports of the first and second chambers may be offset from each other by a distance that may correspond to a pitch of the grooves in the circumferential direction divided by the number of the groove groups. For example, if the pump includes a single pump chamber, the outlet ports may be offset from each other by a distance that may correspond to half the pitch of the grooves. As a result, the phases of pulsations of the fluid from the first and second chambers may be shifted from each other by a cyclic period of the pulsations divided by the number of the groove groups. Therefore, the pulsations may be canceled when the flows of the fluid from the first and second chambers converged at the converging channel.
According to another aspect of the present teachings, the first groove group and the second groove group may be offset from each other in the circumferential direction. In addition, the outlet ports of the first and second chambers also may be offset from each other. The offset distances may be appropriately determined in response to the number of the groove groups.
According to another aspect of the present teachings, the first chamber and the second chamber communicate with each other, so that the pressure within the first chamber and pressure within the second chamber may be balanced with each other. As a result, the pulsations in the discharged fluid may be further reduced or minimized.
According to another aspect of the present teachings, the fluid is a fuel that is supplied to an automobile engine. Therefore, the pump may be configured as a low noise fuel pump that is advantageously incorporated into an automobile in order to reduce noises.


Set retarded cement compositions which are substantially non-thinning at high temperatures are provided. The compositions are comprised of hydraulic cement, sufficient water to form a pumpable slurry, a set retarder and a galactomannan gum which has been treated with a hydrophobing agent whereby the hydration rate of the gum is retarded at temperatures below about 120.degree. F. and at pH levels above about 10. The delayed hydration of the treated gum offsets the thinning of the cement compositions at temperatures above about 120.degree. F. Methods of cementing subterranean zones penetrated by well bores utilizing the cement compositions are also provided.

1. Field of the Invention
This invention relates generally to high temperature set retarded well cement compositions and methods, and more particularly, to set retarded cement compositions which are substantially non-thinning at high temperatures and methods of cementing with such compositions.
2. Description of the Prior Art
In cementing operations carried out in oil, gas geothermal and water wells, a hydraulic cement is normally mixed with sufficient water to form a pumpable slurry, and the slurry is pumped into a subterranean zone to be cemented by way of a well bore penetrating the zone. After placement, the cement slurry sets into a hard mass.
In primary cementing whereby casing and/or liners are bonded within the well bore to the subterranean zones penetrated thereby, cementing is accomplished by introducing a cement composition into the annular space between the casing or liner and the well bore. Generally, the cement composition is pumped downwardly within the casing or liner to the bottom thereof and then upwardly into the annulus.
One or more of the zones adjacent the cemented annulus can, and often do, contain fluids under pressure. In order to prevent such pressurized fluids from entering and flowing through the cement composition containing annulus, the cement composition density is increased by including a weighting material such as hematite therein. Fluid loss reducing and other additives are also commonly used in well cement compositions.
Another problems often encountered in well cementing relates to the rate at which the cement composition develops gel and compressive strengths after being placed. In order to allow enough time to mix the cement composition on the surface and then pump it down the well bore and into a desired location therein, a variety of set retarding additives have been utilized. While set retarding additives successfully extend the pumping time between mixing and setting of cement compositions, they are temperature sensitive, i.e., the higher the temperature which a cement composition including such an additive will be exposed to, the greater the quantity of additive required. A problem which arises in the cementing of deep high temperature wells wherein the cement composition must contain relatively high quantities of set retarding additive is that excessive thinning of the cement composition often takes place. Such thinning leads to the settling of solids in the cement composition and the separation of free water therefrom which can bring about undesirable consequences, e.g., bridging, water pockets within the cement column, poor bonding, etc. In deviated wells and geothermal wells, free water can be responsible for fluid migration to other formations, gas leakage and collapsed pipe.
Prior attempts to solve high temperature thinning of set retarded cement compositions have included combining conventional viscosifying agents such as substituted celluloses or bentonite with the compositions. Generally, however, the use of such viscosifying agents results in high surface viscosities which in turn makes mixing and pumping difficult, time consuming and expensive.
By the present invention, improved set retarded well cement compositions for cementing deep hot wells and methods of using such compositions are provided. The set retarded cement compositions are substantially non-thinning at high temperatures while having normal surface viscosities and other properties.

High temperature set retarded well cement compositions and methods


A differential charge pump with common mode and active regulators is presented. Either type of regulator may be used to improve the performance characteristics of the differential charge pump. The active regulator increases the output range of the differential amplifier. The common mode regulator establishes the common mode voltage of the differential charge pump. The common mode voltage is established independently from external circuitry and does not use a feedback path. The common mode regulator may also be used to establish a mid-rail voltage, which may be used to further improve the output range of the differential amplifier.

As Integrated Circuits (ICs) continue to become more advanced, the transistors that are used to construct them continue to decrease in size. Decreases in transistor size create changes in operating specifications associated with smaller transistors. Such changes include decreased operating voltages and tighter common mode voltage tolerances.
One type of device that is affected by decreased operating voltage and tighter common mode voltage tolerances is a charge pump. Charge pumps are fundamental components of many types of devices. For example, a charge pump may be used to adjust the amount of voltage applied to a low pass filter in a phase locked loop. One such charge pump (a differential charge pump) is illustrated in FIG. 1. Charge pump 10 includes a current steerer 12 which is coupled to receive a source current from a current source 14 and a sink current from a current sink 16. The current steerer distributes the source and sink current to output terminals NEG 18 and POS 20. Signals applied to a differential control (differential input terminals 22A-D) may be used to determine a duty cycle associated with the amount of time the source and sink currents are steered to a respective output terminal.
The output terminals 18 and 20 may each be coupled to a capacitor that uses the source and sink currents to charge and discharge. By changing the duty cycle, via the differential inputs 22A-D, the amount of voltage stored on a particular capacitor may be adjusted. For example, if the capacitors are used in a loop filter (in a phase locked loop), the voltage level on each capacitor may be used to differentially control the output frequency of a voltage controlled oscillator.
Because the current steerer 12 is comprised of Field Effect Transistors (FETs) 24-27, decreasing operating voltages (which may be associated with decreasing transistor sizes) have a direct impact on the output current range of current steerer 12. This becomes apparent by examining nodes 28 and 30. The maximum voltage at node 28 and the maximum voltage at node 30 limit the maximum range of output voltage available for input voltages at FETs 24-27. For example, as operating voltages decrease, a larger percentage of an operating voltage intended for FETs 24-27 may be distributed across current source 14 and current sink 16. When this happens less voltage is available for nodes 28 and 30, and as a result, the output current range of current steerer 12 is reduced.
Another shortcoming with current charge pumps is common mode voltage drift. Common mode voltage drift occur when small asymmetries in the charge pump 12 (or asymmetries in the circuit referencing the charge pump) may cause the positive or negative DC voltage across output terminals 18 and 20 to drift to an undesirable voltage level. For example, due to statistical variations that occur in manufacturing (i.e., semiconductor processing), FET 24 may have a smaller channel length (ΔL), channel width (ΔW), and/or threshold voltage (ΔVt) than FET 25. Over time, small differences in current resulting from an asymmetry may cause a capacitor referencing output terminal 20 to store a small increment of charge at each clock cycle. Another capacitor referencing output terminal 18 may not store this increment of charge. A DC voltage, therefore, is established between output terminals and it may grow, or drift, with each clock cycle.
Current charge pumps employ a feedback mechanism that monitors the DC, or common mode, voltage. By monitoring the common mode voltage through a feedback path, and adjusting the charge pump based on the feedback, a feedback mechanism may compensate for the asymmetry. This may be done by adjusting the duty cycle applied to the current steerer 12, for example. Unfortunately, the feedback mechanism increases the complexity of the charge pump and produce additional overhead. The problems associated with asymmetry may also be further exacerbated with decreased transistor sizes.
Therefore there is a need for a charge pump that has an output range that is not restricted by device scaling and processing asymmetries.

Differential charge pump with open loop common mode


A burner having two ignition electrodes and a bracket is provided. The bracket is arranged on the outer surface of the burner and the ignition electrodes are held, at in each case three points of their periphery, in a fixed position using the bracket. A gas turbine with the burner is also provided.

One of the important components of a gas turbine is the so-called combustion chamber in which fuel is burnt with the aid of an oxidizer. The oxidizer typically involves air. The hot gas produced during combustion in the combustion chamber is conveyed onwards to a turbine.
What is referred to as the burner is located on the side of combustion chamber facing away from the turbine. This is used for igniting the fuel or the fuel-air mixture and is equipped with ignition electrodes for this purpose. The fuel and the air are injected through openings of the burner into the combustion chamber. The ignition electrodes are arranged in the vicinity of these openings and ignite the gas flowing past there. To this end an ignition spark is generated by applying an ignition voltage between two ignition electrodes. This ignition spark is present during the entire ignition duration. To obtain an optimum ignition spark a specific gap must be maintained precisely between the tips of the ignition electrodes.
Previously the ignition electrodes were frequently fixed to the outside surface of the burner with the aid of a clamp. In such cases the ignition electrodes are clamped rigidly in the clamp with the aid of a screw arranged centrally between the ignition electrodes. Typically the support surfaces of the ignition electrodes rest on their full circumference on their clamp which can for example have a round cross section. In the area of the clamp the ignition electrodes are usually surround by a ceramic shroud. The ceramic shroud is used for electrical insulation of the ignition electrodes and thus reduces the heat-related expansion. Fluctuations in the surface quality of the ceramic and inaccuracies in the form and the position of the clamp can lead to the ignition electrodes not being able to be fixed correctly. The fixing is either too firm or too loose. In the event of the fixing being too film the thermal expansion of the ignition electrodes is prevented and in the event of the fixing being too loose undesired vibrations of the ignition electrodes occur.
Typically the ignition electrodes are not arranged centrally between a so-called diagonal mesh and a burner carrier, since the clamps used for fixing the ignition electrodes are frequently screwed to a cam which has a certain height because of the minimum screw depth. The distance from the diagonal mesh is thus small and the result can be a sparkover in this area if the gap at this point is smaller than at the so-called spark gap at which the ignition sparks are to be generated. The result of this is that the burner involved can no longer be ignited directly.
A further difficulty of the ignition electrode fixings used previously lies in their sensitivity to impacts during installation and dismantling and also during transport of the burner. The ignition electrode glued into a ceramic normally does not rest directly on the burner. This can thus quickly result in bending and breakage of the ignition electrodes which makes it necessary to replace the ignition electrodes.

Three-point fixing arrangement of ignition electrodes of a burner


Methods, and systems, including computer programs encoded on computer-readable media, for managing content associated with a content campaign of a content provider are disclosed herein. In one aspect, the present disclosure is directed to a system of generating and updating online content using standardized tagged data. The system may periodically crawl a document that includes one or more document reference tags. The system may identify at least one document reference tag and corresponding tagged data. The system may receive a request for content to display. The system may select an item of content comprising a content reference tag corresponding to the at least one document reference tag. Responsive to the request for content, the system may replace the content reference tag with the corresponding tagged data to assemble an item of content. The system may transmit the assembled content for display.

Content providers often sell their products or services using the Internet. A content provider may manage a website with multiple webpages publishing information and content related to products or services offered by the content provider. These webpages may be created manually by webpage administrators. Alternatively, the webpages may be generated automatically based on content management systems and/or inventory control systems. For example, for an online retailer, the webpages for the retailer's products can be automatically generated based on content in a product and inventory database. As a result, the content provider may have numerous webpages to manage and keep track of.
To promote products and services on the Internet, the content provider may create multiple online content items that mention product details (e.g., product description, product price, etc.). The content provider may have a separate online content item (e.g., advertisement) for each product or service promoted on their webpages. However, information and content on the content provider's webpages relating to products being offered (e.g., product price) frequently changes.

Generating and updating online content using standardized tagged data