A method of inactivating microorganisms such as viruses within a fluid such as a biological fluid is disclosed. The method includes the steps of providing a UV reactor, which may take the form of an elongated generally annular reaction chamber surrounding at least one elongated UV lamp, moving the fluid within the reaction chamber in a primary flow directed along the length of the UV lamp, and inducing a circulating secondary flow within the fluid with the secondary flow being superimposed on the primary flow. As the fluid moves through the reaction chamber in the primary flow, it is circulated repeatedly toward and away from the UV lamp in the circulating secondary flow to provide uniform and controllable exposure of the entire volume of fluid to ultraviolet radiation. Microorganisms such as viruses are thus inactivated while desirable components in the fluid, such as proteins, are preserved without the use of a free radical scavenger.

Sterilization of fluids is an essential step in the manufacture of many pharmaceutical products and foodstuffs. Its goal is the reliable elimination of microorganisms, including viruses, while preserving, as intact as possible, the desirable components of the products. Sterilization may be required of biological fluids, such as nutrient media for fermentation, various blood products, and fluids bearing active pharmaceutical proteins. In the food industry, sterilization of fluid such as milk products is common.
In terms of food sterilization, the selection of a particular sterilization technique frequently is governed by how the procedure will affect the shelf life or the palatability of the food. While the greatest concern in the food industry is bacterial or fungal contamination, dairy products also may carry the additional risk of viral or prion contamination. Elimination or inactivation of such microorganisms is a prerequisite to commercial distribution of these products.
In contrast to the food industry, the choice and use of a sterilization technique in the pharmaceutical industry is subject to the strict demands and regulations imposed upon all pharmaceutical agents that are to be directly administered to an animal or human. There is particular concern about contamination of biological fluids such as pharmaceutical products by viruses, which may be co-isolated from a natural source or introduced during a biotechnological process. For the sterilization of pharmaceutical products, a multi-step process historically has been employed to inactivate, or remove, or reduce viral contaminants. Each step in the process is based on different operational principles to ensure a reduction in the viral load within a fluid preferably by at least four orders of magnitude while preserving the viability of proteins and other desirable components of the fluid.
Irradiation of biological and other fluids with ultraviolet (UV) light has been employed as a method for inactivating undesirable microorganisms. Irradiating plasma and blood products, for example, with UV-light to inactivate viruses was known during WW II. UV-treatment of blood derivatives is especially useful for treating uncoated, heat-stable viruses. Thus, Chin et al., Photochem. & Photobiol. 65, 432-435 (1997) teaches that irradiation of plasma products with UV-light leads to inactivation of the hepatitis A virus and parvoviruses.
UV-irradiation may inactivate microorganisms and/or viruses by generating mutagenic alteration of their genetic material. Above a minimum dose of radiation, the microorganisms lose their reproductive capacity. UV-irradiation damages nucleic acid by creating intrastrand nicks and inducing nucleotide photodimerization, both of which disrupt nucleic acid replication. Through such mechanisms, UV-irradiation can be an effective means of inactivating undesirable microorganisms within biological and other fluids. Unfortunately, the energy of short wavelength UV light also can damage sulfur-containing cysteine bridges and methionine peptide bonds and induce aromatic amino acid side reactions, thereby disrupting the structural and functional integrity of the very proteins that often are the desired end-products of the irradiated fluid. Thus, an inherent problem in the application of UV-irradiation techniques is controlling the irradiation of a fluid so as to ensure sufficient radiation exposure to inactivate undesirable microorganisms within a fluid while at the same time minimizing or eliminating UV-radiation damage to desirable proteins and other components within the fluid.
Traditionally, UV reactors have been used for the UV sterilization of biological fluids. Generally, a UV reactor includes a source of UV radiation such as, for example, one or more elongated tubular bulbs or lamps. In one configuration, an annular reaction chamber with a predetermined width is formed around and encloses the lamp and fluid to be irradiated is pumped or otherwise moved through the chamber, where it is exposed to UV light from the lamp. In another configuration, a UV source or sources may surround and radiate inwardly into a central tubular reaction chamber. In either case, flow rate, light intensity, chamber width or diameter, and reactor length are selected for a particular fluid to ensure, as much as possible, the most effective UV radiation dosage for deactivating undesirable microorganisms while conserving the viability of the desirable components of the fluid.
A problem with the use of UV reactors for irradiating fluid with ultraviolet light results from the finite width of the reaction chamber and the laminar nature of the fluid flow along the chamber. More specifically, as the fluid flows along the chamber, the UV radiation intensity in the treated fluid decreases relatively rapidly as a function of distance from the radiation source. This is due to many factors including the natural inverse-square law of radiation intensity as a function of distance from a source and the absorption characteristics of the fluid and the proteinaceous material supporting the infectious particles. In any event, microorganisms and viruses within layers of the fluid that flow along the outside of the reaction chamber farther from the radiation source receive no or a reduced dosage of radiation. These microorganisms are, therefore, inactivated slowly or not at all. On the other hand, microorganisms in layers of fluid that flow along the inside of the reaction chamber closest to the radiation source receive increased dosages, and in many cases overdoses, of radiation, which, in some cases, is high enough to cause significant damage to desirable proteins and other components in these layers of the fluid. The result is unpredictable and inefficient sterilization and higher levels of damage to desirable components.
Attempts to address these limitations have led to the development of thin-layer or thin film UV reactors in which the width of the reaction chamber and thus the thickness of the fluid layer adjacent the UV source is maintained relatively thin to reduce the detrimental effects of radiation intensity gradients in the fluid (see e.g. Kallenbach et al., Cur. Stud. Hematol. Blood Transfus. Basel 56, 70-82, (1989); Habel et al., J. Immunol. 56, 273-279(1947); Milzer et al., J. Immunol 50, 331-340 (1945). Oppenheimer et al., Am., J. Pub. Health. 49, 903-923, (1959)). The goal is to ensure that all of the fluid is constrained to a region of relatively smaller radiation intensity change as it moves along the radiation source. Thus, the difference in intensity at various layers within the fluid flow is theoretically controlled.
While thin-film reactors have been somewhat successful on a smaller scale, they are problematic in that they can only be scaled up to industrial production throughput with difficulty. This is because keeping the film thickness small and constant can only be realized by increasing the diameter of the reactor and thereby increasing the cross-sectional area of the film to accommodate the desired higher throughput. On an industrial scale, this necessary condition leads to unmanageably large reactors. One attempt to circumvent this problem is suggested in U.S. Pat. No. 5,133,932 which discloses a cylindrical thin-film UV-irradiation reactor in which the area of the film exposed to the UV-light is increased by corrugating the surfaces of the reaction chamber. However, the realized increase in throughput with such a device is marginal at best and still insufficient to accommodate large scale industrial production.
A further limitation of and problem with traditional UV-irradiation reactors is the unfavorable flow profile and dynamic conditions of fluid films when in laminar flow along the radiation source. More specifically, in a laminar flow there is no or very little fluid exchange normal to the flow direction. Thus, as mentioned above, fluid layers farther from the source receive a smaller radiation dose than fluid layers close to the source. Furthermore, the flow velocity profile within a confined laminar flow is such that the flow velocity is relatively low adjacent to the walls of the reaction chamber and is substantially higher intermediate the walls. Thus, fluid closest to the wall of the reaction chamber adjacent the light source flows more slowly and is exposed to the UV radiation substantially longer than fluid between the walls of the reaction chamber. Accordingly, to produce the minimum radiation dose necessary for inactivation of microbial contaminants in the most rapidly flowing fluid layers, the average residence time of the fluid in the reactor must be increased. This leads, however, to increased radiation dosage in the slower moving boundary layers of the fluid flow and consequent increased probability of undesired damage to desirable components in these layers. Thus, destruction of desirable components in the boundary layers due to overexposure is virtually inevitable.
One adverse result of overexposure in some layers of the fluid is the generation of free radicals, which become entrained in the flow and which have adverse effects on desirable components of the fluid. Attempts to minimize damage caused by free-radical generation as a result of overexposure typically include the use of free-radical scavengers in the fluid. Earlier studies have suggested that the use of free-radical scavengers can reduce indirect damage to proteins (Chin et al., Photochem. Photobiol. 65, 432 (1997). Chapman et al. in U.S. Pat. No. 5,922,278 discloses a UV-irradiation sterilization of biological fluids wherein free radicals are scavenged by a scavenging agent. Clark et al. in U.S. Pat. No. 5,786,598 discloses high intensity pulses of short wavelength light to deactivate microorganisms. Morgalis-Nunno et al., U.S. Pat. No. 6,087,141, discloses the use of light in the wavelength range of 340-400 nm (UVA) rather than short wavelengths of about 280 nm or less. Protection of the desired functionality of the fluid is afforded by adding a free-radical scavenger in the form of psoralen. Morowitz et al., U.S. Pat. No. 5,981,163 teaches the addition of quenching protective agents during irradiation deactivation of viruses. While such techniques attempt to deal with the free-radicals generated in the fluid, none address the problems, such as overexposure, that result in the formation of such free-radicals in the first place.
The disruption of the laminar fluid flow through UV reactors has been proposed as a solution to some of the forgoing problems. For example, tangential-flow ring-slot reactors have been proposed as a means to disrupt and induce mixing within the laminar flow layers of a UV reactor. EP 803472 A1 discloses a reactor for UV irradiation of a fluid having an annular or ring-slot reaction chamber surrounding a UV radiation source. The fluid inlet into the reaction chamber is orientated so that the fluid enters tangentially into the chamber in hopes of generating fluid cross-mixing. U.S. Pat. No. 5,433,738 discloses an irradiation reactor for the irradiation of water that includes a helical guide with circular cross section in hopes of generating fluid cross-mixing.
The tangential inflow solution has proven problematic in that the fluid flow through the reaction chamber rapidly reverts, due to wall friction and other hydrodynamic factors, to a fully axial and laminar profile directed along the longitudinal axis of the chamber. The Dean vortices, which are theoretically postulated at least for the area of tangential inflow, and which are intended to promote cross-exchange of the reaction medium within the reaction chamber, are surprisingly not present according to visual studies and CFD-investigations (flow simulation). Tangential entry ring-slot reactors, therefore, afford only a limited solution to the problems discussed above.
A need therefore exists for a method of sterilizing a fluid such as a biological fluid with UV radiation that ensures adequate exposure to inactivate undesirable microorganisms, while simultaneously minimizing or eliminating damage to desirable components in the fluid.
A further need exists for an improved method of inactivating microorganisms in a fluid reaction medium with UV radiation that eliminates the need to use free radical scavenging or quenching agents.
There is also a need for a method of sterilizing biological fluids that is effective at deactivating undesirable microorganisms while preserving the viability of desirable components without the use of scavengers and that is scalable to commercially viable production throughput.
It is to the provision of a method that addresses these and additional needs that the present invention is primarily directed.

Method of inactivating microorganisms in a fluid using ultraviolet radiation


A pneumatic tire comprises a carcass ply made of organic fiber cords extending continuously from one edge to the other and turned up around bead cores to form a pair of turned-up portions and a main portion disposed therebetween, the carcass cords having a difference in elongation percentage, wherein the difference Ea-Eb of the elongation percentage Ea in the main portion from the elongation percentage Eb in the turned-up portions is in the range of from 0.5% to 2.0%.

The present invention relates to a pneumatic tire, more particularly to a low noise tire with an improved carcass structure.
In recent years, there is a great demand for low noise tires. It has been known that tire noise decreases if the tire rigidity is decreased. However, this greatly deteriorates the running performance of the vehicle, such as its steering stability. Thus, in order to improve the steering stability, if additional reinforcing layers are disposed in the tire sidewall portions, the tire weight increases and the tire uniformity tends to be disturbed, and furthermore the ride comfort deteriorates. Thus, the decrease in the tire rigidity is nullified.
It is therefore, an object of the present invention to provide a pneumatic tire, in which the noise is reduced without sacrificing the steering stability, ride comfort, and the like.
According to one aspect of the present invention, a pneumatic tire comprises a tread portion, a pair of axially spaced bead portions with a bead core disposed therein, a pair of sidewall portions, a carcass comprising a carcass ply turned up around the bead cores to form a pair of turnup portions and a main portion disposed therebetween. The main portion extends between the bead portions through the tread portion and sidewall portions. The turnup portions are disposed axially outside of the main portion. The carcass ply is made of organic fiber cords extending continuously from one of the ply edges to the other, and is characterized by the carcass cords having a difference in elongation percentage between the main portion and turnup portions. The difference (Ea-Eb) of the elongation percentage Ea in the main portion, from the elongation percentage Eb in in the turnup portions is in the range of from 0.5% to 2.0%.
The elongation percentage means the elongation percentage specified in the "Testing Method for Chemical Fiber Tire Cords" of Japanese industrial standard JIS-L1017, Section 7.7 (Elongation Percentage in Constant Load) and 7.1.1 (Test in Standard Condition).
Preferably, the carcass consists of only the above-mentioned turned-up carcass ply, and the radially outer ends of the turnup portions thereof are disposed radially outward of the maximum tire section width position.
Therefore, in comparison with the turned-up portions, the main portion has a higher elongation percentage, and the carcass cord tension is decreased. As a result, vibrations which are received by the tread portion when running on rough road surfaces are hindered from spreading. Further, the tire resonance frequency shifts downward from the resonance frequency of the car bodies. Thus, the noise can be effectively reduced.
As the turned-up portions have a lower elongation percentage, the tire maintains its precise shape and dimensions, and the running performance such as steering stability can be maintained.
If the difference in the elongation percentage is less than 0.5%, the noise reducing effect can not be obtained. If the difference is more than 2.0%, the noise reducing effect does not increase any more, and the steering stability is lowered.
Another to another aspect of the present invention, a method of making a pneumatic tire, having a carcass ply of organic fiber cords turned up around bead cores to form a pair of turned-up portions and a main portion disposed therebetween, comprises the steps of building a raw pneumatic tire having the carcass ply and vulcanizing the raw pneumatic tire in a mold, wherein the carcass cords are provided with a difference in elongation percentage between the main portion and the turned-up portions, the difference (Ea-Eb) of the elongation percentage Ea in the main portion, from the elongation percentage Eb in the turned-up portions being in the range of from 0.5% to 2.0%. The difference in elongation percentage is provided, for example, by heating the main portion before vulcanizing the tire.

Method of making a pneumatic tire with different carcass cord elongations between main portion and turned-up portions


An apparatus to facilitate machine learning matrix processing is disclosed. The apparatus comprises a memory to store matrix data one or more processors to execute an instruction to examine a message descriptor included in the instruction to determine a type of matrix layout manipulation operation that is to be executed, examine a message header included in the instruction having a plurality of parameters that define a two-dimensional (2D) memory surface that is to be retrieved, retrieve one or more blocks of the matrix data from the memory based on the plurality of parameters and a register file including a plurality of registers, wherein the one or more blocks of the matrix data is stored within a first set of the plurality of registers.

Deep learning algorithms are currently being implemented in various machine learning applications, such as audio/video recognition, video summarization, etc. Neural networks of various forms (e.g., Convolutional Neural Networks (CNNs), Recurrent Neural Networks (RNNs), Long Short-Term Memories (LSTMs), etc.) are applied to perform such workloads due to their highly parallel nature. Machine learning applications typically implement matrix multiplication workloads having a significant percentage of zeros (e.g., sparse matrices).
Deep learning (or machine learning) kernels often have low compute utilization due to resources required to perform input data layout manipulation prior to execution of math instructions. Most frameworks (e.g. Tensorflow) standardize a data layout format that cannot be directly consumed by machine learning operations. For example, a weight matrix may need to be transposed prior to performing multiplications. However, performing a transpose operations (or other operations, such as transform operations) in software consumes an excessive quantity of clock cycles and reduces the performance of the graphics compute.


An imaging apparatus includes a foreign substance removal member configured to move along a surface of an optical member to remove foreign substances, a shutter blade configured to open and close an photographic optical path, the shutter blade being disposed closer to an object side than the optical member, and a cover plate configured to restrict an operation range of the shutter blade toward the optical member side, wherein the cover plate has an opening larger than the photographic optical path, and an area other than the photographic optical path of the opening includes a standby position for the foreign substance removal member, and at least a part of the foreign substance removal member is positioned inside the opening.

1. Field of the Invention
The present invention relates to an imaging apparatus, such as a digital camera, including a foreign substance removal mechanism to remove foreign substances adhering to the surface of an optical member.
2. Description of the Related Art
In recent years, an imaging apparatus, such as a digital camera, using an image sensor has been widely used. However, particularly, in a single-lens reflex type digital camera, a problem has arisen in which foreign substances may adhere to the surface of an optical member, such as an image sensor or a filter, thereby causing a captured image to contain an image of the foreign substances. The foreign substances are mostly dust, which enters from the outside to an imaging aperture when a lens is detached, and abrasion powder generated by operation of mechanical elements, such as a quick return mirror or a focal-plane shutter.
The foreign substance may be removed by spraying air on the surface of an optical member. However, it is difficult to completely remove the foreign substance. In such a case, work to wipe the surface of the optical member is required to remove the foreign substances. However, wiping the surface of the optical member by hand may cause surface irregularity or scratches on the surface of the optical member.
Accordingly, some apparatuses with simple mechanism have been proposed to remove foreign substances adhering to the surface of the optical member. A method of providing an optical member with vibration and dropping foreign substances adhering to the surface has been proposed and has actually been mounted on a camera. However, if the vibration is provided unnecessarily too much, it may cause such a failure that the vibrating optical member is broken. Thus, the amount of the vibration to be provided thereto has a limit. Accordingly, there has been a problem that a vibration type foreign substance removal apparatus cannot completely remove foreign substances having large adhesion.
Some other methods for removing foreign substances adhering to the surface of an optical member have been proposed. Japanese Patent Application Laid-Open No. 2005-292404 discusses a method for exposing the surface of an image sensor to the outside, allowing a foreign substance attracting member to enter the inside of a photographic optical path from the outside, and bringing the attracting member into contact with the surface of the image sensor with a suitable contact pressure to remove foreign substances.
In Japanese Patent Application Laid-Open No. 2001-298640, a method is discussed in which a wiper member is incorporated in a camera. The wiper member is brought into contact with the surface of an image sensor and scans thereon by motor drive.
In Japanese Patent Application Laid-Open No. 2006-119461, a method is discussed in which an electrically charged member scans the surface of an image sensor, without contact therewith, to remove foreign substances therefrom using electrostatic force.
An apparatus discussed in Japanese Patent Application Laid-Open No. 2005-292404 is an accessory apparatus which is attachable to an outside of a camera to be operated by a user. When cleaning is required, a lens must be removed and the accessory apparatus must be attached, so that the operation is intricate. Accordingly, there may be a problem for a user to miss a photo opportunity.
In an apparatus discussed in Japanese Patent Application Laid-Open No. 2001-298640, a wiper member or the like is incorporated inside a camera, so that foreign substance removal operation can be simply performed at any timing. However, since the wiper member is disposed between a shutter blade and an image sensor, this may cause restrictions on the arrangement of elements. In particular, the traveling surface of the shutter blade is away from an imaging surface, thus reducing shutter efficiency. Accordingly, there has been a problem that moving body stop capability is inferior at a high shutter speed.
Further, when shutter efficiency needs to be kept as high as possible, it is necessary for a wiper member to be thinned. Accordingly, there has been a problem that the wiper member is inferior in strength and location accuracy. In particular, when the wiper member is limited to a thin material, a spring constant is increased even if it is an elastic body. Therefore, it is difficult for the wiper member to give a constant pressure on the surface of an image sensor. The pressure significantly varies due to a slight accuracy error of the wiper member. Thus, this may result in such a state that foreign substances cannot be removed or it may cause scratches on the surface of the image sensor.
An apparatus discussed in Japanese Patent Application Laid-Open No. 2006-119461 uses an electric charge unit also as a shutter blade, so that restrictions on the arrangement of elements and deterioration in shutter efficiency can be reduced to be minimum. However, an increase in inertia moment of the shutter blade causes problems that a high shutter speed cannot be achieved and the shutter blade is inferior in durability. Further, when an electric charge member is separately provided and scans between the shutter device and the image sensor, similar to the apparatus discussed in Japanese Patent Application Laid-Open No. 2001-298640, this causes restrictions on the arrangement of elements. In addition, the shutter blade traveling surface is away from the imaging surface, so that the shutter efficiency is decreased and the moving body stopping capability is inferior at a high shutter speed.

Imaging apparatus having foreign substance removal member which overlaps shutter blade moving locus in optical axis direction


A discharge light-emitting device includes a transparent first substrate, at least two first electrodes formed on the first substrate, a transparent second substrate, at least two second electrodes formed on the second substrate, sidewalls configured to form a discharge space with the first substrate and the second substrate so that the at least two second electrodes are inside the discharge space, at least two first fluorescent layers formed on a discharge space side of the first substrate, and at least two second fluorescent layers formed on a discharge space side of the second substrate.

1. Field of the Invention
The present invention relates to a discharge light-emitting device that emits light due to discharge at a space between electrodes charged with any discharge gas such as xenon, and to a contact image sensor utilizing the discharge light-emitting device as a light source.
2. Description of the Related Art
Hitherto, a discharge light-emitting device utilizing spontaneous discharge of gas, with which a space between electrodes is charged, has been known as a light source employed in a contact image sensor for reading graphic form or the like. Generally in the contact image sensor, any original held between a platen and a glass plate is irradiated with a discharge light-emitting device, and reflected light thereof passing through a rod lens array is transformed into electrical signals, thus the original comes to be read.
This known discharge light-emitting device is constructed such that any discharge gas such as xenon is charged into a space between two substrates opposed to each other. When ac current of about 1 to 2 KV is applied to the space between electrodes disposed on each substrate, discharge gas is ionized and discharges ultra-violet rays by which a fluorescent substance is energized and emits light.
FIG. 6 is a cross-sectional view showing a conventional discharge light-emitting device disclosed in the Japanese Patent Publication (unexamined) No. 2002-134064. Referring to this drawing, a discharge light-emitting device 1 includes a first substrate 2 composed of a glass plate. A first electrode 3 is formed on this first substrate 2. A dielectric layer 4 is formed on the first substrate 2 so as to cover the first electrode 3. A second substrate 6 includes a recess formed by a flat facing part 6a, an inclined part 6b and a leg part 6c. The second substrate 6 is mounted on the first substrate 2, thus forming a discharge space 9 with the recess.
A second electrode 7 is formed on the external surface opposite to the discharge space 9 formed on the second substrate 6. In the discharge space 9, a fluorescent layer 5 is composed of a lower fluorescent substance layer formed on the dielectric layer 4 and an upper fluorescent substance layer formed on the second substrate 6. A sealing layer 8 forms the discharge space 9 through bonding the first substrate 2 and the second substrate 6. The discharge space 9 is charged with any discharge gas such as xenon. The inclined part 6b is formed at a portion joining to the facing part 6a of the second substrate 6 and to the first substrate 2 so as to make about 45 degrees with respect to the facing part 6a of the second substrate 6. The fluorescent layer 5 is not formed at the discharge space 9 portion on this inclined part 6b. Accordingly, discharge light generated in the discharge space 9 outgoes through the inclined part 6b to outside.
The first substrate 2 is rectangular in external shape, and the rectangular first electrode 3 is formed in the longitudinal direction thereof. One end in the longitudinal direction of this first electrode 3 is connected to a high voltage power source located outside. The dielectric layer 4 is rectangular in external shape covering the first electrode 3. The fluorescent layer 5 is rectangular in shape and is formed on the dielectric layer 4.
FIG. 7 is a sectional view showing a construction of a contact image sensor in which the discharge light-emitting device shown in FIG. 6 is used as a light source. In the drawing, the discharge light-emitting device 1 acts as a light source of a contact image sensor 10. Referring to FIGS. 6 and 7, a housing 12 includes a mounting part 18 on which the discharge light-emitting device 1 is mounted, and supports horizontally thereon the first substrate 2 of the discharge light-emitting device 1. A glass plate 15 is also supported on the housing, and the second substrate 6 of the discharge light-emitting device 1 is disposed in close contact with the lower side of the glass plate 15. The inclined part 6b of the discharge light-emitting device 1 is disposed at a position near the irradiation point of an original 16 carried by a platen roller. On the supposition that inclination of the inclined part 6b is 45 degrees, light outgoing from this inclined part 6b comes to be the irradiation point. As indicated by the arrows in the drawing, the light reflected from the original 16 is converged through into the rod lens array 14, and contents of the original 16 are read through photoelectric transfer by a sensor 13 mounted on the circuit board 11.
In general, brightness at the original surface (original surface illuminance) is in proportion to brightness of light source and in inverse proportion to the square of distance between light source and original surface. Therefore, if it is possible to shorten the distance between the light-emitting surface of the light source and the original surface, the original surface illuminance can be increased even in the case of using the light source of the same brightness. Further, when reducing unnecessary space between the light source and original, it becomes possible to restrain disturbance due to reflection and disperse from the portions other than the original to be read, thereby enabling to read the original with high accuracy.
However, in the construction in which the discharge light-emitting device 1 is built in only on one side of the rod lens array 14 as shown in FIG. 7, a shadow may be projected due to corrugation or level difference in the original 16. This shadow may make the read contents of the original 16 indefinite or unclear, and moreover brightness of the discharge light-emitting device 1 may be insufficient. To cope with this problem, it may be an idea that the discharge light-emitting device 1 is built in on each of the two sides of the rod lens array 14. It is certain that, as a result of such arrangement, the indefiniteness due to the shadow of corrugation is overcome, and brightness is improved. But a problem exists in that increase in cost is unavoidable.

Discharge light-emitting device and contact image sensor utilizing the same


An electric roller skate in the present invention includes a shoe body, a roller frame, a driver, a rotation speed detection device, and a controller. The controller receives rotation speed information of the rotation speed detection device and accordingly controls the driver to start to drive the rollers to rotate. The present invention further provides a control method for the electric roller skate described above. The controller is capable of controlling the driver to start to drive the electric roller skate to slide according to the detected rotation speed information. Through the above arrangement, the solution can help a user to skate in a more labor-saving manner and reduce fatigue of the user. Meanwhile, the driver is started in a mode closer to a conventional sliding mode, is higher in convenience and intelligence, reduces use difficulty and makes user experience better.

Roller skates are commonly known as roller skating shoes and have a certain fitness and entertainment function. As a leisure article in life, they are well received by vast consumers. Meanwhile, along with the development of the times and the demands of different consumer groups, electric roller skates are researched and developed gradually in the market. Such roller skates have a relatively high speed and can save more strength for users, so they serve as a relatively convenient means of transport.
Existing electric roller skates still have great deficiency in the control over sliding although they can achieve effects of saving strength and reducing fatigue of users. Typically, the existing electric roller skates are started or stopped when a human body applies loads to sensing switches of shoe bodies. It is difficult for beginners to learn this control mode. Meanwhile, this control mode cannot be changed any time according to sliding conditions of the users due to the not high intelligence degree, resulting in relatively poor user experience.

Electric roller skate and control method thereof


The invention concerns a microelectronic circuit for activation or respectively deactivating at least one second input/output (2, 3), or second “buffer”, which receives a deactivation command (21, 31) corresponding to a combination of a general activation, or respectively deactivation, command (StopPadB) and of an information item representing the activated, or respectively deactivated, state (12, 22) of at least a first buffer, so that the said second buffer(s) is/are only activated, or respectively deactivated, when the said first buffer(s) is/are already activated, or respectively deactivated, to keep to a predetermined sequence of activation, or respectively deactivation, of the said buffers (1, 2, 3).

The field of the invention is that of microelectronic circuits. More precisely, the invention relates to the activation or deactivation of inputs/outputs, or of sets of inputs/outputs, (also termed hereinbelow "input/output buffers", when there are problems, and particularly when there is a power failure.
A specific field of application is to smart card readers, for which it is necessary to keep to a specific deactivation sequence when there is a power failure. However, the invention may be applied more generally to any circuit having to keep to a particular input/output activation and/or deactivation sequence, particularly when there is a power failure.
In the known systems, when a circuit undergoes a power failure, a power failure detector (PFD) enables emergency passing to a reset mode which prevents the microprocessor or a similar component, and internal memories, from performing erroneous operations.
For example, in the case of a conventional circuit having a typical supply VCC of 3V, and 2.7V minimum, the voltage Vreset for passing into reset mode is 2.4V, to protect the circuit (operating at x MHz) when the logic VCCmin is about 1.2V. The circuit then functions, but at a low frequency.
In certain applications, it is necessary to keep to a particular deactivation sequence when there is a power failure. This is the case for smart card readers. These have three communication inputs/outputs:    CCLK (clock of external smart card)    CRST (reset of this smart card)    CIO (enabling data transfer).
During a transaction between the smart card reader and a smart card, there is an exchange of information. During this transaction, and when there is a power fall-off, it is necessary to stop the communication. Thus a specification ISO7816 stipulates that CRST has first to be forced to 0, then CCLK and finally CIO.
When the power fall-off detector PFD places the microprocessor in reset, operations may no longer take place. According to the prior art, it is then this PFD reset command which places the three inputs/outputs of the card to 0 at the same time.
In fact, the microprocessor can no longer space these three communications over several clock cycles, since it is stopped and therefore no longer functional when the microprocessor is under reset.
Consequently no present circuit is effective, nor responds to the future ISO standard.

Microelectronic circuit for activation or deactivation of at least one input/output, corresponding smart card reader and deactivation method


A motor protecting circuit is provided. A first terminal of each of high-side transistors is coupled to a power supply voltage. A second terminal of each of low-side transistors is grounded. Second terminals of the high-side transistors are respectively connected to first terminals of the low-side transistors. An overvoltage detector circuit is coupled to the power supply voltage of an output circuit. When the overvoltage detector circuit determines that the power supply voltage of the output circuit is higher than a voltage threshold, the overvoltage detector circuit outputs an overvoltage detected signal to a controller circuit. According to the overvoltage detected signal, the controller circuit controls a driver circuit to turn on at least one of the high-side transistors and at least one of the low-side transistors at the same time.

Circuit components of electronic products produce heat during operation, causing air circulating throughout an enclosed space (especially an enclosed chassis of a server) to be heated up. As a result, other circuit components may be damaged due to overheating. Therefore, fans must be disposed in the electronic products to cool down the circuit components of the electronic products.
A controller circuit of the fan can control a driver circuit to drive a plurality of transistors of a bridge circuit connected to a motor, such that fan blades of the fan rotate with the motor. However, during commutation of the motor, a residual current flows through the transistors of the bridge circuit and parasitic diodes thereof to a power supply voltage source. Therefore, a transient voltage suppressor diode or a Zener diode may be connected between the power supply voltage source and the bridge circuit, thereby preventing the residual current from flowing to the power supply voltage source.
However, due to the configuration of the diode, the residual current only charges an input capacitor such that an inrush voltage of the input capacitor as a power supply voltage is inputted to the bridge circuit. As a result, the transistors of the bridge circuit and other circuit components are damaged, and noise is generated.


A fuel preconditioning system for use with a pulse detonation combustor (PDC) makes use of a heat source to pyrolyze fuel prior to injecting it into the PDC for detonation. The fuel is decomposed into a more detonable form by pyrolysis in a conditioner that applies heat to the fuel in the absence of oxidizer. The heat may be provided by a hot section of the engine, including the walls of the PDC itself. The conditioned fuel is fed to the PDC and detonated.

This invention relates to propulsion or power systems utilizing detonative combustion for energy conversion, that use liquid hydrocarbon fuels, and more particularly to a fuel preconditioning system for use with detonation-based propulsion and power systems.
Detonation based combustion systems can be used in place of ordinary combustors to enhance the performance of certain systems. Because many fuels that one might want to use in such systems, such as aviation fuels, consist of a range of relatively heavy hydrocarbons that do not readily detonate, relatively high detonation initiation energy is required for detonation. In a similar manner, known natural gas fuels, which are primarily methane, are not readily detonable compared to other known fuels. To facilitate enhanced detonation, at least some known detonation systems mix oxygen with the fuel to create a more detonable mixture that is ignited in a detonation initiator chamber. Although the initiator chamber creates an over-driven detonation that initiates a fuel-air mixture detonation in the detonation chambers, such systems require the addition of oxygen tanks or oxygen generation systems, and as a result, any benefits gained from using such pulse detonation systems may be offset by the weight gain to the system.
Therefore, there is a continued need for techniques to enable the use of hydrocarbon fuels in detonation based combustion systems.

This patent is subject to a terminal disclaimer.

Fuel preconditioning for detonation combustion


A method and apparatus for identifying a sample in a container, provide for the container with the sample being disposed relative to a resonator, a high-frequency signal being coupled into the resonator for exciting a resonant mode of the resonator, the resonant electric field of the resonator penetrating part of the sample in the container, the resonance curve of at least one resonant mode being measured with and without the sample, and the sample being identified based on the determined change in the resonance frequency compared to a measurement without sample.

The invention relates to a method for identifying a sample in a container and to an associated measuring device.
A method and an apparatus for measuring the complex dielectric constant of a material by evaluating the degree of detuning of an RF resonator, which is introduced by the presence of the material, is known From DE 43 42 505 C1, in which an RF transmitter for transmitting high-frequency electromagnetic fields of selectable frequency into the RF resonator, a receiver for the resonator field, and a measuring circuit connected to the receiver are provided, whereby the amplitude of the received radio-frequency signals can be determined by way of the measuring circuit.
A variety of methods are known for determining the dielectric properties of materials, which typically are indicated as the dielectric constant Fr and the loss angle tan (δ), or as the complex dielectric constant ∈=∈′−i∈″. Such methods are used, for example, for determining the moisture of materials. These methods are based on the high dielectric constant and the large loss factor of the water in the material and are highly important in industry, for example in measuring the moisture in chemicals, foods, tobacco, coffee, and the like.
In the resonance methods for determining moisture by way of microwaves, the material to be analyzed is introduced into a cavity resonator and the detuning of the cavity resonator caused by the presence of the material is measured, the resonance curve being followed and measured by varying the irradiation frequency. The shift in the resonance frequency and the increase in the resonance half-width value, or the change in quality of the resonator, can be used to derive the dielectric constant, and hence the water content of the material, if the material composition and density are known. For this purpose, calibration curves are generally required, which are obtained by prior measurement of respective substances having different known moisture levels. In most known methods, a separate measurement of the material density is also required.
A method for determining the material moisture content with the aid of a cavity resonator is known from DE 40 04 119 A1 in which, for a known material, by way of a defined selection of the field course of the cavity resonator in the region of the sample to be analyzed, the material moisture content and material density can be determined independently of each other, using a calibration curve wherein the resonance frequency determined by following the resonance curve and the half-width value of the resonance line are determined and evaluated. Again, it is necessary to introduce the material to be analyzed into the cavity resonator in the form of a sample.
From the article "Ein Dielektrizitätskonstanten-Messplatz zur Untersuchung optischer Kristalle im Mikrowellenbereich (A dielectric constant measuring station for the analysis of optical crystals in the microwave range)" in: Kristall und Technik, Volume 10, No. 6, 1975, pp. 695-700, by E. Wehrsdorfer et al., a method similar to that described above is known, wherein the dielectric constant of a sample is determined by loading a cavity resonator operated in the microwave range with a sample. The change in resonance frequency and quality caused by the presence of the sample in the cavity resonator is determined by measuring the resonance curve after introducing the sample into the cavity resonator.
The printed East German patent specification 1 38 468 discloses a method for measuring the complex dielectric constant of dielectric plates which are metallized on one side. For the measurement, a dielectric resonator is placed on the non-metallized side of the plate, and the resonator TE011 mode is excited. The metallized side of the plate acts as the end point of the resonance-capable system. The change in resonance frequency compared to the case in which the dielectric resonator is placed on a metal plate can then be used to determine the dielectric constant of the plate material if the thickness is known.
Recently, commercially available moisture sensors allow the sensor to scan the sample within milliseconds. In this process, the product moisture can be continuously detected as a function of the density and weight, with changes in the product temperature being compensated for automatically. These methods are used, for example, in the manufacture of products in the ceramics industry.
The disadvantage of the known methods, which are based on HF technology, is that they are limited to determining the complex dielectric constant of a sample having known dimensions. This means that the geometry and the exact dimensions of the sample must be known in order to determine the real and imaginary parts of the complex dielectric constant based on a measured quality and frequency shift.
It is also disadvantageous that, in order to determine the dielectric constant, a sensor must be brought in contact with the sample, which should be avoided, particularly with hazardous samples, such as acetone or other flammable fluids.

Method for identifying a sample in a container, e.g. when conducting a traveler survey in the check-in area, by determining the resonance frequency and the quality of a dielectric resonator to which the container is arranged


A method for detecting damage in the structure includes a plurality of steps. These steps include determining first data indicative of pre-damage modal parameters of the structure, determining second data indicative of post-damage modal parameters of the structure, and identifying at least one location of the damage based upon first and second data applied to an indicator function. The damage detection method is capable of localizing damage in the structure, and subsequently estimating the magnitude of such damage, using limited modal information.

Structures constructed of various materials are critical in many applications such as large space structures, oil rig platforms, industrial piers, microwave towers, marine structures, bridges, buildings, aircraft, spacecraft, turbine hubs and rotors, chemical manufacturing systems, power poles, and biomedical structures as used for example in monitoring the strength of bones and joints. Damage in these structures may cause severe economic consequences and possibly loss of human life. Moreover, the design characteristics of a passive or an active controller depend upon the mechanical properties of the structure to be controlled. If a change in mechanical properties occurs at any point in the structure, a corresponding adjustment should be made in the control system if the original control objectives are to be continually satisfied. Therefore, it is desirable to non-destructively monitor changes in the mechanical properties of structures. The locations and magnitudes of changes in mechanical properties may provide the basis for decisions regarding repairs or future uses of a structure.
To allow continued use of a tested structure, non-destructive damage detection (NDD) approaches are utilized. Many techniques of NDD are currently available, including but not limited to X-radiography, ultrasound, neutron radiography, eddy currents, optical holography, acoustic holography, and thermography. These techniques have been incorporated in various prior art approaches to NDD applied to large scale structural systems. However, the prior art approaches have several shortcomings. First, the prior art approaches are local (spanning at most only a few feet at a time) rather than global (spanning the entire structure) in their scope of damage detection. Second, the prior art approaches require the application of additional theoretical analysis (i.e., fracture mechanics or continuum damage theory) to define and assess identified damage. Third, they can only be applied to accessible portions of a structure. Fourth, the prior art approaches are extremely costly when applied to large scale structural systems.
Structural damage may be defined as deviations of geometric or material properties of a structure that may cause unwanted displacements, distortions or vibrations in the structure. One such measure of damage is stiffness loss at one or more locations in a structure. Stiffness loss may be detected by non-destructive vibration measurement techniques. Vibration techniques may locate flaws and defects that might otherwise allude other methods such as ultrasonics or visual inspection. Furthermore, vibrational techniques may increase the efficiency of overall inspection by first localizing areas of distress for more detailed examination by local methods.
For any structure, the natural modes of vibration depend only upon the mechanical characteristics of the structure and not upon the excitation. In many instances, the required modal vibration responses can be obtained by measuring the modal responses at only a single point on the structure. Using this method, operators may be alerted to handle life-threatening structural conditions or to confirm possible structural damage.
It is established that changes in the modal vibration response of a structure may reflect deterioration in that structure. However, there is considerable debate among practitioners regarding how to interpret the changes in the modal response to yield information on the location and magnitude of damage. Practitioners of vibration measurement have long been aware that decreases in the vibrational response frequencies of a structure indicate damage to the structure. However, prior art approaches incorporating vibration measurement techniques fail to accurately relate changes in vibrational response frequencies to the specific locations and severity of damage to the structure. Instead, many prior art approaches only detect the existence of damage in the structure. Recent approaches incorporating vibration measurement techniques have successfully related changes in vibrational response frequencies of a structure to the specific locations and severity of damage to the structure. However, even these approaches may be inaccurate or impractical in many instances, as for example when damage is extensive or when complex structures are analyzed.
Therefore, a need has arisen for an accurate and practical method and apparatus for damage detection.

Apparatus and method for damage detection


A system for multi-modal cockpit interface during surface operation of an aircraft comprises a head tracking device, a processing element, and a full-color head worn display. The processing element is configured to receive head position information from the head tracking device, to receive current location information of the aircraft, and to render a virtual airport scene corresponding to the head position information and the current aircraft location. The full-color head worn display is configured to receive the virtual airport scene from the processing element and to display the virtual airport scene. The current location information may be received from one of a global positioning system or an inertial navigation system.

Aircraft surface operations involve taxiing of an aircraft from a terminal gate (or generally from the ramp or apron area) to an assigned runway in preparation for takeoff, or movement of an aircraft from a runway to a terminal gate after landing. Taxi instructions, at towered, control airports, are verbally issued by ground control using radio-telephony to the aircraft. When an aircraft taxies across the airport, it travels on a series of assigned taxiways based on directions received from a ground controller. Ground controllers at busy airports may be directing the movement of several dozen aircraft at any particular time. A taxiing aircraft will often have to travel across active runways to reach its destination; therefore, it is critical to coordinate surface operations with takeoff/landing instructions to prevent runway incursions. A runway incursion is "any occurrence in the airport runway environment involving an aircraft, vehicle, person, or object on the ground that creates a collision hazard or results in a loss of required separation with an aircraft taking off, intending to take off, landing, or intending to land" (Runway Safety, Federal Aviation Administration, available at http://www.faa.gov/runwaysafety/). Even when there is no risk of collision, an aircraft taking off or landing on the wrong runway can result in a crash if the actual runway used is too short to accommodate the aircraft.
Ensuring that an aircraft uses the correct, safe route from the gate to the runway (and vice versa) requires both that the ground controller provide correct instructions to the aircraft and that the aircraft precisely follow those instructions. Signs and other markings help a pilot identify the taxiways and runways. These signs and markings may be confusing, especially to a relatively inexperienced pilot or to a pilot at an unfamiliar or confusing airport. Further, reduced visibility at night or during inclement weather can cause a pilot to misread or fail to see these signs and markings.
To assist in surface operations, pilots utilize airport maps. These maps were traditionally paper charts. However, pilots can now utilize an electronic moving map or "electronic flight bag" (EFB), which displays a digitized map of the airport. The EFB may be coupled with the aircraft's navigation system such that the aircraft's current position is displayed on the map, thereby enabling the pilot to readily see if the aircraft is on the assigned taxiway/runway, and to anticipate turns.
During surface operations, it is also critical that the pilot watch for other aircraft and service vehicles (such as catering trucks) which are nearby and may constitute a collision hazard. This is particularly important when visibility is reduced. As such, it is desirable that a pilot minimize the percentage of taxiing time spent looking down at charts, instruments, or the like, and maximize the percentage of time spent looking out the windshield (also termed windscreen). While a pilot is looking down at charts, etc., the pilot is said to be "heads-down." While a pilot is looking out the windshield, the pilot is said to be "heads-up."
During surface operations, it is also critical that the pilot(s) listen for their aircraft call sign for updates, modifications, revisions, or other changes to taxi clearance. The potential for a collision hazard exists if the pilot(s) do not receive the new clearance instructions or misunderstand the taxi clearance due to errors of omission or commission. Due to the quality of Very High Frequency (VHF) radio telephony currently used for airport surface operations, a significant hazard exists for mistakes made during read-back, callback, and hear-back of taxi instructions. During restricted visibility or other conditions that significantly increase workload for the pilot(s), the incidence of these types of occurrences and potential consequences increase, particularly for long or complex taxi clearance. Pilots may be "heads-down" during receiving and copying of taxi clearances.
One known technology for displaying navigational and safety information within an aircraft is a heads-up display (HUD). The HUD projects information onto a transparent display screen, such that the pilot can see the projected information while also having an unobstructed view outside the aircraft. This information can be of great value to a pilot, particularly in low visibility situations. However, there are several drawbacks of the HUD. The HUD has a limited field of view (typically 30 degrees horizontal by 24 degrees vertical), so that objects outside of this field of view cannot be represented. Additionally, HUDs only project a monochromatic (typically green) display, thereby preventing the use of multiple colors to help make a crowded display more readable. HUDs are also typically quite expensive, and must be integrated into the airframe of an aircraft.

Multi-modal cockpit interface for improved airport surface operations

The United States of America as represented by the United States National Aeronautics and Space Administration


Thin-walled rubber articles for use contact with living tissue or with materials to be delivered to living tissue are prepared from aqueous latex of either natural rubber or synthetic cis-1,4-polyisoprene by vulcanization to produce both carbon-carbon and carbon-(sulfur)n-carbon crosslinks, the vulcanization being performed in the absence of any compounding components that contain secondary amine groups or any components that have a tendency to produce nitrosamines. While sulfur activators may be included, it is preferable that no sulfur accelerators at all be included. Thin-walled rubber articles formed from the latex surprisingly exhibit a combination of high tensile strength, high ultimate percent elongation, and low 500% tensile modulus. The process is particularly effective in the manufacture of thin-walled articles from synthetic cis-1,4-polyisoprene.

1. Field of the Invention
This invention resides in the field of thin-walled rubber articles, and particularly those that are made from latex and vulcanized to produce both carbon-sulfur and carbon-carbon crosslinking bonds. The goal of this invention is to provide thin-walled rubber articles with favorable tensile characteristics including high tensile strength, high ultimate elongation, and low tensile modulus, and to do so without creating allergic reactions or health concerns that are attributable to some of the chemicals that are commonly used in the manufacture of sulfur-vulcanized rubber.
2. Description of the Prior Art
Natural and synthetic rubber have been used extensively as materials of construction for thin-walled medical devices and personal items. Examples of articles made from these materials are surgical and examination gloves, finger cots, catheter balloons and cuffs, uterine thermal ablation balloons, condoms, contraceptive diaphragms, in-dwelling urinary drainage catheters, male external urinary drainage catheters, breather bags, surgical tubing, baby pacifiers, baby bottle nipples, and drug infusion bladders. Because of the mechanical stresses imposed on these devices during use, the walls of these devices must have a high tensile strength combined with a low 500% tensile modulus. The rubber is vulcanized in any of various ways to achieve structural integrity, but high tensile strength and low tensile modulus are most readily achieved when vulcanization is achieved by the use of sulfur, i.e., by crosslinking of the polymer chains with carbon-sulfur bonds.
The highest durability and flexibility are achieved by a rubber film that is seamless and of uniform thickness. Thin-walled rubber devices formed from latex, particularly by dip-molding, are particularly favorable for these reasons. Latex can be processed without breaking down the molecular weight of the rubber, whereas dry-rubber methods, which utilize high shear to comminute the rubber and combine it with other compounding ingredients for processing, tend to degrade the molecular weight.
Vulcanization with sulfur has traditionally been performed in the presence of sulfur vulcanization accelerators. The first compound found to be capable of accelerating the reaction between sulfur and natural rubber was aniline (first used in 1906), and various other compounds bearing similarities to aniline were subsequently developed that were less toxic and produced greater acceleration activity. Included among these are:                mercaptobenzothiazoles, such as 2-mercaptobenzothiazole, bis(2,2′-mercaptobenzothiazolyl)disulfide, and zinc 2-mercaptobenzothiazole,        sulfenamides, such as N-tert-butyl-2-benzothiazolesulfenamide, N-cyclohexyl-2-benzothiazolesulfenamide, N-oxydiethylene-2-benzothiazolesulfenamide, and 4-morpholino-2-benzothiazolesulfenamide,        dithiocarbamates, such as bismuth dimethyldithiocarbamate, cadmium diethyldithiocarbamate, copper dimethyldithiocarbamate, zinc dimethyldithiocarbamate, and other metal dialkyldithiocarbamates, and piperidinium pentamethylenedithiocarbamate        thiurams, such as dipentamethylene thiuram disulfide, dipentamethylene thiuram hexasulfide, tetramethylthiuram disulfide, tetrabenzylthiuram disulfide, and tetra-n-butylthiuram disulfide,        guanidines, such as diphenylguanidine and di-ortho-tolylguanidine,        thioureas, such as diphenylthiourea, ethylenethiourea, and trimethylthiourea,        xanthates, such as dibutyl xanthogen disulfide and zinc di-iso-propylxanthate, and        dithiophosphates, such as copper O,O-di-iso-propylphosphorodithioate and zinc O,O-di-n-butylphosphorodithioate
The most widely used accelerators in the above list are those that contain secondary amine groups (RR′N—, as opposed to primary amine groups RNH—), such as dialkyl amino groups, cycloalkylamino groups, and morpholinyl groups. Secondary amine groups are found, for example, among the sulfenamides, the dithiocarbamates and the thiurams. An unfortunate consequence of the inclusion of these accelerators is their tendency to produce an adverse reaction in individuals with whom the articles come into contact. The reaction is commonly referred to as a Type IV allergy, which is mediated by T cells, generally occurs within six to 48 hours of contact with the rubber article, and is localized to the area of the skin where contact is made. Secondary amine-containing accelerators are also referred to as nitrosatable amines since they are susceptible to reaction with atmospheric nitrogen oxides during mixing, milling, extrusion, molding, calendaring, curing, and even warehousing and storage, to produce nitrosamines, which have been designated as potential human carcinogens. Some of these nitrosamines are N-nitroso-di-n-butylamine, N-nitrosodiethanolamine, N-nitrosodiethylamine, N-nitrosodimethylamine, N-nitrosodiisopropylamine, N-nitrosodi-n-propylamine, N-nitrosomorpholine, N-nitrosopiperidine, and N-nitrosopyrrolidine.
Natural rubber itself is responsible for adverse reactions in certain individuals, and these as well are addressed by certain embodiments of this invention. One type of adverse reaction to natural rubber is an indirect reaction that arises as a result of irritant dermatitis. Although not an allergic reaction, irritant dermatitis can cause breaks in the skin which can provide the components of the rubber, including proteins, increased access to the body's immune system and ultimately an allergic reaction. Another type of adverse reaction to natural rubber is a systemic allergic reaction known as a Type I allergy, which is caused by IgE antibodies to the proteins in natural rubber. This is an "immediate" reaction, occurring within thirty minutes of exposure, and its symptoms include hives, rhinitis, conjunctivitis, asthma, and in rare cases anaphylaxis and hypotension.
These adverse reactions to natural rubber can be prevented by using a suitable synthetic rubber. The use of deproteinized natural rubber has been proposed, but it has not been shown that deproteinized natural rubber eliminates the problems entirely. Various synthetic elastomers have been used as well. Nitrile rubber and polychloroprene, for example, have been used in the manufacture of surgical gloves, medical examination gloves, and dental gloves. These materials do not however offer the high resiliency and low tensile set values of natural rubber. Silicone rubber has been used for catheter balloons, but its tensile strength is lower than that of natural rubber and must be compensated for by an increased wall thickness. Polyurethanes have also been used, particularly in dip-molded catheter balloons. Polyurethanes have very high tensile strength, but they lack the resiliency and low tensile set values of natural rubber and are therefore unsuitable for devices that are required to undergo large degrees of expansion during use and then be able to return to their original configuration. Gloves have also been prepared from styrene-ethylene-butylene-styrene tri-block copolymer, but this material has very high tensile set values, a characteristic that causes the glove to exhibit undesirable "bagging," i.e., to remain stretched after use.
The closest substitutes for natural rubber in terms of overall performance are synthetic cis-1,4-polyisoprene and rubber compositions which are comprised of substantial amounts of synthetic cis-1,4 polyisoprene. There are considerable differences however between synthetic cis-1,4-polyisoprene and natural rubber in terms of molecular structure. The polyisoprene in natural rubber has a molecular weight of from about 1,000,000 amu to about 2,500,000 amu, while the molecular weight of synthetic cis-1,4-polyisoprene ranges from about 250,000 amu to about 350,000 amu (both expressed as number averages). Lower molecular weight polymers generally have lesser tensile properties, including lower tensile strength. Synthetic cis-1,4-polyisoprene also has a lower degree of branching, lower symmetry, and lower intermolecular forces. All of these characteristics contribute to and affect the tensile properties of the polymer.
Certain medical devices, such as surgical and other medical gloves, require a relatively low tensile modulus to remain comfortable during use. If the tensile modulus is too high, the user's hands may become fatigued over time as progressively more strength is required to stretch the glove material. This is particularly problematic with gloves that are to be used for a prolonged period of time such as during a long surgical procedure. The importance of a low tensile modulus is recognized in the standardized testing procedure ASTM D3577, which sets standards for the tensile properties. The standards require that the 500% modulus value be 7 MPa or less for synthetic gloves, and 5.5 MPa or less for natural rubber gloves. Low tensile modulus values are also important for condoms to promote ease of donning, and for catheter balloons where ease of inflation is beneficial. A low tensile modulus is also of value in elastomeric drug infusion bladders by making it easier to fill the bladder with a drug solution.
Another tensile property affecting the usefulness of certain medical and personal devices is tear strength, which is important in preventing premature failure of the device. Baby bottle nipples and baby pacifiers also benefit from high tear strength since this prevents the child's teeth from severing the nipple or pacifier during use. It is generally known that rubbers that are crosslinked only through carbon-carbon bonds have inferior tear strength compared to rubbers that contain sulfidic and/or polysulfidic crosslinks.
A still further tensile property that is important to the satisfactory performance of rubber medical devices is ultimate elongation. Increasing the ultimate elongation value is believed to reduce the incidence of breakage in use. This is of benefit for example to condoms and catheter balloons, as well as to surgical gloves which are easier to don if they have a high ultimate elongation value. The importance of high ultimate elongation is also recognized in the standard testing procedure ASTM D3577, which requires an ultimate elongation of at least 650% percent for synthetic gloves, and at least 750% for natural rubber gloves. In the case of catheter balloons, a high ultimate elongation lowers the stress that is placed on the balloon when inflated and thereby helps prevent premature failure. It is well known that for any given rubber composition, sulfur-vulcanized articles exhibit higher elongation than do equivalent articles which contain only carbon-carbon crosslinks.
The following is a survey of disclosures that may constitute prior art relevant to certain aspects of the invention set forth herein. The relevance of each of these disclosures will be apparent from the succeeding sections of this specification and claims. All patents and published materials cited throughout this specification are incorporated herein by reference in their entirety.
The use of cis-1,4-polyisoprene latex compositions for use in medical devices or medical device components is well known. Preiss et al. in U.S. Pat. No. 3,215,649, disclose the use of a sulfur-vulcanized cis-1,4-polyisoprene. McGlothlin et al. in U.S. Pat. No. 6,329,444 disclose the use of sulfur-free, free-radical-cured cis-1,4-polyisoprene for use in dip-molded medical devices. Leeper et al. in U.S. Pat. No. 4,938,751 disclose the use of reinforced free radical crosslinked cis-1,4-polyisoprene in elastomeric bladders. The Leeper et al. patent addresses molded (non-latex) rubber articles, but still of fairly thin walls. Both the McGlothlin et al. and Leeper et al. patents cite the high level dimensional stability of the cured polyisoprene materials, primarily due to the carbon-to-carbon crosslinking. McGlothlin et al. state that tensile set values of less than 5% can be achieved, while Leeper et al. reveal that a low frequency hysteresis less than about 10% and a stress relaxation less than about 10% can be achieved. Neither McGlothlin et al. nor Leeper et al. disclose the use of sulfur in combination with organic peroxides to improve the physical properties of synthetic polyisoprene.
Zabielski et al. in U.S. Pat. No. 4,724,028 disclose the use of a free radical curing mechanism to cure medical injection sites made from cis-1,4-polyisoprene via an extrusion process. Noecker et al. in U.S. Pat. No. 6,051,320 disclose the use of reinforcing agents to improve the tensile strength of free radical cured natural rubber for use in medical devices. Noecker et al. admit that ". . . the sample rubber latex gloves according to the invention are somewhat inferior in tensile strength and modulus of elasticity than the conventional rubber latex gloves formed using sulfur and related curing agents." The tensile strength cited by Noecker et al. for natural rubber is 21 to 24 MPa. There is no reference at all to synthetic polyisoprene. Neither the Zabielski et al. nor Noecker et al. patents provide any suggestion of combining sulfur and free-radical curing mechanisms to improve tensile strength.
Class in U.S. Pat. No. 6,245,861 states that compositions cured exclusively with peroxides are thought to have shorter crosslinks which are less flexible than comparable crosslinks from sulfur-cured compositions and therefore peroxide-cured compositions are believed to exhibit less resistance to abrasion and cut growth. While not directly referring to synthetic polyisoprene, Class addresses problems that generally arise with free-radical-cured rubber compounds.
The use of coagents has been suggested as a means to overcome the objections to pure peroxide cures. Typical coagents as disclosed by Class include trimethylolpropane trimethacrylate, triallyl isocyanate, pentaerythritol tetramethacrylate, trimethylolpropane trimethacrylate, triallyl isocyanate, pentaerythritol tetramethacrylate, and low molecular weight 1,2-polybutadiene. Class states that coagents can increase the modulus and hardness of a peroxide-cured composition. While suggesting the combination of both peroxide and sulfur in the same composition, Class does not suggest that sulfur is a coagent for the peroxide. Class specifically discloses however the use of traditional accelerators when sulfur is used. Class does not mention the use of polyisoprene, and does not mention medical device applications. In many medical device applications, the increase in hardness and modulus is not desirable, especially for thin-walled products such as condoms and gloves.
Blok et al. in U.S. Pat. No. 6,300,421 provide a comprehensive overview of the role of coagents in the curing of EPDM elastomers. Blok et al. further disclose the use of elemental sulfur as a coagent for peroxides in the curing of EPDM rubber. Also disclosed is the potential use of polyisoprene as a component of the EPDM formulation. Blok et al. further state that in order to minimize, or retard, the occurrence of side reactions, co-agent(s) may be used in combination with the peroxide curative to react with and stabilize the free radicals formed during the curing process. In this manner, a co-agent tends to improve the overall crosslinking efficiency and thereby lead to a higher cure rate and state of cure. This is well known to those having skill in such art. Blok et al. do not suggest that any carbon-sulfur bonds are actually formed. The sulfur is likely acting as a traditional coagent to help the efficiency, rate and state of cure, which will generally increase the tensile modulus and reduce the ultimate elongation of the rubber. Blok et al. do not disclose anything related to natural rubber or synthetic polyisoprene, or to medical devices or latex applications.
Magei et al. in U.S. Pat. No. 4,218,548 disclose the use of sulfur as a coagent for ethylene propylene rubber. As in Blok et al., there is no suggestion that the sulfur is acting as a vulcanizing agent. There is also no mention or suggestion by Blok et al. of the use of peroxide compounds with polyisoprene or for the curing of medical devices.
Sartomer Company, Inc., Exton, Pa., USA, manufactures a large number of products for use as peroxide coagents in curing elastomers. Sartomer has published a technical bulletin entitled "Coagent Selection for Peroxide Cured Elastomers." While not specific to synthetic polyisoprene, the bulletin contains references to co-agents for elastomers in general. Table 15 of the bulletin provides a generalized cure property comparison between a peroxide-only curing system, an accelerated sulfur-only curing system, and seven different peroxide-coagent curing systems. The data show that tensile modulus and hardness both increase with the addition of coagents, as compared to both accelerated sulfur-curing systems and to peroxide-only curing systems. This is not desirable from the perspective of making highly elastic medical devices such as condoms, gloves, balloons, and surgical tubing. The bulletin does not disclose the possibility of using sulfur in combination with peroxide.
An article by McElwee and Lohr entitled "Comparing curing systems: peroxide-coagent versus sulfur-accelerator in polyisoprene" appears in Rubber World, Kippincott & Peto, Inc, Akron, Ohio, USA, Volume 225, No. 2, November 2001, pages 41-44. The article states that a peroxide-coagent curing system has the best characteristics of both peroxide and sulfur cure systems, i.e., high tensile strength, high tear strength, high modulus, and outstanding flex and heat-aged properties. While several acrylic and other coagents are disclosed, the use of sulfur as a coagent is not disclosed. Comparisons are made between sulfur-cure, peroxide-cure, and peroxide/coagent cure in terms of several physical properties. The comparisons show that the tensile modulus obtained with the peroxide-coagent system is higher than that obtained with the other cure systems, indicating that the peroxide-coagent system achieves a greater state of cure. The Shore A hardness is also shown to be significantly higher with the peroxide-coagent system than for either the accelerated sulfur-cure or the peroxide-only cure, results that are consistent with other prior art observations. The article does not reveal the advantage of using sulfur in conjunction with peroxide to cure polyisoprene in terms of achieving a lower modulus and higher elongation without increasing the hardness of the material.
Stevenson in U.S. Pat. No. 4,695,609 A1 discloses a process for preparing a vulcanized rubber article using sulfur vulcanization with a combination of accelerators which include a dihydrocarbyl xanthogen polysulphide and less than 0.4 part by weight of nitrosatable materials. The accelerator combination is disclosed for use with synthetic polyisoprene. The process described in the patent reduces the amount of nitrosamine formation during curing, and achieves a significant reduction in the use of toxic conventional nitrogen-containing accelerators, but does not allow for the complete elimination of such compounds. The use of peroxide and sulfur in combination for vulcanization of polyisoprene is not disclosed.
Stevenson et al. in U.S. Pat. No. 5,254,635 disclose a means for reducing the amount of nitrosatable compounds needed in rubber formulations. While not specifically citing synthetic polyisoprene, Stevenson et al. state that the use of potentially nitrosatable materials such as secondary and tertiary amines may need to be added as supplemental accelerators to provide for a satisfactory degree of cure when the rubber to be cured is a synthetic rubber. Stevenson apparently was still able to limit the amount of these undesirable substances to about 0.2 phr. While this is a low level, its is still an undesirable amount for the fabrication of medical devices and components. Again, there is no disclosure of the use of peroxide and sulfur in combination for vulcanization of synthetic polyisoprene.
Virdi in U.S. Pat. No. 6,162,875 discloses the use of zinc diisononyldithiocarbamate as a sulfur accelerator which is thought to produce safer nitrosamines that are likely to be non-mutagenic. Vulcanizates produced by the Virdi process still contain nitrosamines, however.
Puydak et al. in U.S. Pat. No. 5,073,597 disclose the use of sulfur as a coagent for peroxide in curing EPM and EPDM rubbers for use in making dynamically vulcanized alloys that can be processed by thermoplastic forming methods. While the inclusion of synthetic polyisoprene in the composition is disclosed, the role of the polyisoprene is not defined and no mention is made of vulcanization of the optional polyisoprene. No special characteristics are assigned to the peroxide-cured compositions that use sulfur as a coagent. Furthermore, the use of dynamic vulcanized rubber materials is limited and cannot be used to produce high tensile strength, low tensile set rubber materials.
Numerous methods for the vulcanization of peroxide-containing formulations are known. Most of these methods involve excluding oxygen from the rubber composition during the curing process. McGlothlin et al. in U.S. Pat. No. 6,329,444 disclose methods to protect thin films of organic peroxide-containing polyisoprene from oxygen exposure during vulcanization. Verlaan et al. in U.S. Pat. No. 4,808,442 teach several methods to protect organic peroxide-containing rubber compositions from degradation caused by oxygen attack of the rubber. Compression, transfer and injection molding are known methods of protecting such rubber compositions during the curing process.
Organic peroxide-cured rubber particles can be prevulcanized prior to being formed into shaped articles if oxygen is mostly excluded during the prevulcanization process. One such process, in which dicumyl peroxide is used to prevulcanize synthetic latex rubber particles is disclosed by Bayer AG (Obrecht) in WO 02/08328 A1.
Dillenschneider in U.S. Pat. No. 3,937,862 discloses tire sidewalls formed from a mixed sulfur and peroxide vulcanization system (Example 23) with an EPDM polymer having a relatively low molecular weight (Mooney viscosity of 84 at 100° C.). Dillenschneider concludes that the mixed vulcanization system offers no particular advantage over an all-peroxide vulcanization system. While Dillenschneider discloses the use of mixtures of rubbers, some of which may include polyisoprene and/or natural rubber, the patent does not disclose the use of a mixed sulfur and peroxide vulcanization system for polyisoprene-containing blends. All of the disclosed compositions include the use of nitrosatable rubber accelerators. Dillenschneider further states that the use of sulfur in very small amounts, such as from about 0.1 to about 0.3 phr, would be insufficient for vulcanization in the absence of both peroxide and an accelerator.
Wei et al. in U.S. Pat. No. 3,179,718 teach the use of a mixture of peroxide and elemental sulfur to vulcanize blends of highly saturated rubber with butadiene-acrylonitrile rubber. In comparative examples, Wei et al. refer to the curing of natural rubber with a combination of sulfur and peroxide. The form of natural rubber used by Wei et al. was smoked sheet rubber. When compounding natural rubber with a combination of 2 phr of sulfur and 4 phr of dicumyl peroxide, Wei et al. produced a vulcanizate with a tensile strength of 2360 psi and an ultimate elongation of 570%. While Wei et al. suggest that synthetic polyisoprene can be blended with other rubber material and then vulcanized with a sulfur/peroxide curing system, there is no mention of the use of synthetic polyisoprene alone. Nor do Wei et al. disclose the use of latex formulations, or state that the disclosed curing system produces a product with high tensile strength. Nor do Wei et al. mention avoidance of Type I or Type IV latex allergies. Still further, the only rubber articles that Wei et al. address are tire treads, windshield channels, and cable coverings. Thin-film rubber articles are not addressed or suggested.
Mitchell in U.S. Pat. No. 4,973,627 teaches the use of a tire sidewall composition that includes a mixed sulfur and peroxide vulcanization system. The optional inclusion of polyisoprene and/or natural rubber in the sidewall composition is mentioned. The patent expressly states that it is necessary to include sulfur accelerators in the manufacture of the disclosed product.
Podell, Jr., et al. in U.S. Pat. No. 3,813,695 disclose the application of acrylic hydrogel coatings to gloves to serve as donning aids. No disclosure is made of such coatings being used to eliminate the passage of oxygen during the peroxide curing of gloves.
The prior art indicates that thin-walled latex dip-molded rubber articles with a combination of excellent tensile strength, low 500% modulus, and high ultimate elongation, can only be obtained by vulcanization with sulfur in combination with a nitrosatable (i.e., secondary amine-containing) sulfur accelerator. The present invention overcomes this limitation.

Accelerator-free thin-walled rubber vulcanizates from latex


A method is disclosed for preparing carrier wafers for semiconductor device manufacture. The method includes the steps of sorting a plurality of standard carrier wafer blanks into batches by thickness to define a batch of starting carrier wafers that are within a predetermined tolerance of one another, reducing the thickness of the sorted carrier wafers to within 10 microns of a final target thickness, and polishing the sorted carrier wafers to the final target thickness. The polished carrier wafers are mounted to device precursor wafers having at least one semiconductor epitaxial layer on a substrate by joining one surface of a carrier wafer to the epitaxial layer on a substrate. The thickness of the device precursor wafer is then reduced by removing material from the device precursor substrate opposite the joined epitaxial layer.

This application claims priority from Ser. No. 60/60/609,039 filed Sep. 10, 2004. The present invention relates to the manufacture of carrier wafers for use in processing semiconductor wafers. In particular, the invention relates to the manufacture of carrier wafers with properties that enhance the controlled thinning of semiconductor wafers mounted on the carrier wafers.
Silicon carbide (SiC) has emerged over the last two decades as a candidate semiconductor material that offers a number of advantages over other more conventional semiconductor materials such as silicon and gallium arsenide. In particular, silicon carbide has a wide bandgap, a high breakdown electric field, a high thermal conductivity, and a high saturated electron drift velocity, and is physically extremely robust. In particular, silicon carbide has an extremely high melting point and is one of the hardest known materials in the world.
Because of its physical properties, however, silicon carbide is also relatively difficult to produce. Because silicon carbide can grow in many polytypes, it is difficult to grow into large single crystals. The high temperatures required to grow silicon carbide also make control of impurity levels (including doping) relatively difficult, and likewise raise difficulties in the production of thin films (e.g. epitaxial layers) on the material. Because of its hardness, the traditional steps of slicing and polishing semiconductor wafers are more difficult with silicon carbide. Similarly, its resistance to chemical attack make it difficult to etch in conventional fashion.
Nevertheless, based on a great deal of research and discovery in this particular field, including that carried out by the assignee of the present invention, a number of advances have been made in the growth of silicon carbide and its fabrication into useful devices. Accordingly, commercial devices are now available that incorporate silicon carbide for high-power radio frequency (RF) and microwave applications, for other high-power, high-voltage applications, and as a substrate for other useful semiconductor materials such as the Group III-nitrides.
Silicon carbide has particular advantages as a substrate for optoelectronic devices, and in particular light emitting diodes (LEDs). Since silicon carbide can be conductively doped, vertical devices (i.e. devices having anode and cathode contacts on opposite sides of the chip) can be formed. Vertical devices are compatible with most modern LED packaging equipment, which makes packaging the devices easier. In addition, silicon carbide has a small lattice mismatch with gallium nitride and other III-nitride materials.
In many new applications, LED chips are mounted in a flip-chip configuration with the epitaxial side down, permitting light to exit the device through the substrate. Flip-chip mounting is particularly advantageous for devices formed on silicon carbide substrates because of the higher index of refraction of silicon carbide as compared with that of the nitride regions of the devices in which the light is generated. However, silicon carbide can absorb some light passing through it before it is extracted, resulting in a reduced optical extraction efficiency.
Conventional silicon carbide (SiC)-based LEDs have a substrate thickness of approximately 200-500 μm. Since the SiC substrate is not a perfect conductor, the substrate increases the forward voltage (Vf) required to operate the device at a given current level. For example, the C450-CB230-E1000 LED, a typical SiC based device available from Cree, Inc. (Durham, N.C., USA) has a chip thickness of 250 +/+25 μm and a forward operating voltage of 3.5 V at 10 mA forward operating current. Reducing the forward voltage of the device would yield a proportionate reduction in power consumption since P=VI, i.e. the power consumed by the device is equal to the voltage across the device times the current through the device.
Moreover, in many new applications such as cellular phone backlighting, LED chips are packaged as surface mount devices to reduce the thickness of the optoelectronic component, which permits system designers to reduce the overall thickness of end products such as cellular phones. Accordingly, it is desirable to reduce the thickness of the LED chip to further reduce the thickness of an end product.
Accordingly, it is desirable to reduce the thickness of the SiC substrate in order to improve the operating characteristics of devices formed thereon. For example, the silicon carbide substrates may be thinned from their normal thickness down to thicknesses as low as about 100 microns or less.
Because the silicon carbide wafer must be thick enough to provide adequate mechanical stability during epitaxial growth steps, the wafer is ordinarily thinned after epitaxial deposition of the nitride layers and fabrication of devices. In order to thin the silicon carbide, the epiwafer (which comprises a growth substrate on which one or more epitaxial layers have been formed) is ordinarily mounted epi-side down on a carrier wafer such as a second silicon carbide wafer. The backside (i.e. the side opposite which the epitaxial layers are formed) of the mounted growth wafer is then thinned to the desired thickness.
However, problems with the carrier wafer may result in loss of yield from the substrate thinning process. Accordingly, there is a need for better methods of manufacturing carrier wafers, and better resulting carrier wafers.

Method of manufacturing carrier wafer and resulting carrier wafer structures


A protection system for a compressor. The system comprises a compressor having a discharge and including at least one rotor and at least one bearing; a lubrication system including at least one oil recovery device for recovering oil from the compressor, and further including bearing conduit connecting the oil recovery device to the compressor bearing and including rotor conduit for connecting the oil recovery device to the compressor rotors; and an oil protection system. The oil protection system includes a compressor discharge temperature sensor located in the discharge for sensing the temperature of a lubricant/refrigerant mixture discharged by the compressor, a differential pressure sensor located in the bearing conduit for measuring a differential pressure in the bearing conduit, and an oil detector located in the rotor conduit for detecting the presence of oil in the rotor conduit.

This application is related to commonly assigned U.S. patent application Ser. No. 08/924,228, entitled "Liquid Level Sensor" as invented by Ronald W. Okoren, Ali Ameen and Matthew A. Shepeck and filed on even date hereof.
The present invention is directed to an oil flow protection system for an air conditioning or refrigeration system. The system is an active and robust system which avoids compressor failure by stopping compressor operation upon failure of the oil circulation or return system.
The present invention is discussed in terms of screw compressors for air conditioning systems, but is contemplated to apply to all compressors whatever the application. Like many other compressors, screw compressors require oil flow to the compressor so as to lubricate bearings and prevent long term degradation's of the bearings. Additionally, oil flow is needed to seal the rotors in a screw compressor to avoid reduced performance and to cool the rotors to prevent frictional heating.
Oil flow is needed by a compressor to lubricate the bearings and enhance their life. Additionally, in screw and scroll compressors, oil is used to seal the rotors, the absence of such a seal resulting in reduced compressor performance. Also, the lubrication of rotors can prevent frictional heating while cooling the rotors, and can prevent the radial growth and interference of rotors with adjacent compressor components. If the oil circulation system fails and compressor operation is allowed to continue, compressor failure and damage will ultimately result.
U.S. Pat. Nos. 5,431,025 and 5,347,825, both to Oltman et al., are directed to an oil charge loss protection arrangement for a compressor. Essentially both patents disclose comparing the temperature of a liquid in the oil system with the temperature of saturated refrigerant, and generating a signal to shutdown the compressor when the comparison indicates that the differential is off range. These patents are commonly assigned with the present invention and are incorporated herein by reference.
An oil protection system is desired which proves that there is oil in the compressor or that there is an immediately available supply of oil trapped in lines feeding the compressor prior to any starting of the compressor. Additionally, a perfect oil protection system would prove flow in the oil line during compressor operation and prove that the flow is a liquid rather than a vapor or at least is a liquid foam. Additionally, the desired oil protection system should prove that the flow is high in oil quantity (i.e., less than 30% refrigerant by weight).


There is provided a communication device including a communication unit configured to include different communication modes, and an information exchange unit configured to exchange, before the communication unit transmits information to a transmission destination device, an available communication mode and authentication information in advance with the transmission destination device using a communication mode included in the communication unit, the authentication information being used when communication is performed using the communication mode.

The present disclosure relates to a communication device, a communication method, a computer program, and a communication system.
With the advancement of high-resolution image, the amount of data for content of still or moving images is getting larger and larger. A method of sharing content between terminals may be implemented by directly transmitting content from one terminal to another, but a large amount of content data will increase the amount of time necessary to transmit content.
In order to exchange data between terminals, from the viewpoint of security, it is desirable to perform an authentication process in advance between terminals prior to the exchange of data. A technique for performing an authentication process between terminals prior to the exchange of data is disclosed, for example, in Japanese Patent Application Laid-Open Publication Nos. 2010-011058 and 2009-140275. The technique which is disclosed in Japanese Patent Application Laid-Open Publication Nos. 2010-011058 and 2009-140275 employs a short-range communication to perform an authentication process between terminals, but it actually exchanges data using a communication mechanism that is different from the short-range communication.

Communication device, communication method, computer program, and communication system