An improved electro/mechanical connector through which multi-media electrical signals are transported includes a first port with resilient contact tongues, a second port for supporting a coaxial assembly and a third port coupled to a circuit module which receives the multi-media electrical signals on an input terminal splits the multi-media electrical signals into broadband signals which are routed to the coaxial assembly and baseband signals which are routed to the first port. The circuit module also receives broadband signals and baseband signals from the coaxial assembly and first port respectively combines them into the multi-media signals which are outputted on the input terminal.

1. Field of the Invention
The invention relates to electrical couplers and connectors in general and, in particular, to electrical couplers and connectors used in multi-media communication networks.
2. Cross Reference to Related Patent
U.S. Pat. No. 4,885,747, titled "Broadband and Baseband LAN," issued on Dec. 5, 1989, assigned to the assignee of the present invention discloses a multi-media communications network. A device called an F-coupler combines and separates broadband and baseband signals. The present invention discloses an improved F-coupler.
3. Prior Art
The use of electrical couplers and connectors in communications networks is well known in the prior art. Broadly speaking, prior art electrical couplers may be used as electrical splitters or combiners. If used as a splitter, the electrical coupler separates an electrical signal so that it traverses multi paths. If used as an electrical combiner, the coupler combines electrical signals so that it traverses fewer paths. The electrical connector attaches data terminal equipment (DTE) to the communications network. As a result, the DTE inserts electrical signals into the network or receives electrical signals from the network.
U.S. Pat. No. 4,472,691 (Kumar et al) discloses a coupling device which produces a plurality of outputs from a single RF source.
U.S. Pat. No. 4,419,636 (Hong Yu) discloses a low frequency wide band signal coupler which provides bidirectional signal transmission between a controller and a terminal. The coupler can be used as a splitter (signal divider) or signal tap device.
U.S. Pat. No. 3,925,737 (Headley) discloses a signal coupling apparatus which couples radio frequency signals from a primary transmission path to two or more secondary transmission paths.
U.S. Pat. No. 3,566,275 (Schenfeld) discloses a signal splitting circuit which delivers a radio frequency signal and a common DC voltage to a plurality of terminals.
U.S. Pat. Nos. Re. 32,760 (Chandler) and 5,030,114 (Carey et al) disclose connectors with hermaphroditic mating members. Each of the hermaphroditic mating members has a mating face with spaced resilient tongues which contact like resilient tongues of the other member when the connector is in mating relationship and contact shortening members, placed in each of the mating members, when the members are separated.
The above described prior art devices (couplers and connectors) work well in the communications network in which a single type of information is transmitted. Usually, the single type of information is restricted or uses a single sector of the frequency spectrum. For example, most of the above couplers split or combine radio signals which are restricted to the frequency spectrum used to transmit radio signals. However, the newly emerging multi-media technology which transmits multiple types of information (voice, video, data, etc.) on a single transmission media (wire, fiber optic, etc.) uses different sectors of the frequency spectrum and, in that respect, the prior art devices are not suited for the multi-media environment.

International Business Machines Corporation


Methods are provided for hermetically sealing an opening in a reservoir of a containment device. The method comprises applying a polymeric material to an opening in a reservoir of a containment device, the reservoir comprising reservoir contents (such as a drug or a sensor) to be hermetically isolated within the reservoir, the applied polymeric material closing off the opening and forming a temporary seal; and adhering a hermetic sealing material onto the polymeric material to hermetically seal the opening. The reservoir can be a micro-reservoir. The containment device can comprises an array of two or more of reservoirs, and the method comprises hermetically sealing each of the two or more reservoirs.

This invention is generally in the field of methods and structures for hermetically sealing small reservoirs or apertures in devices.
U.S. Pat. No. 5,797,898, No. 6,527,762, No. 6,491,666, and No. 6,551,838 describe devices for the controlled release or exposure of reservoir contents. The devices include a plurality of reservoirs in which the reservoir contents are contained. For example, the reservoirs could contain drug molecules for release or sensors for exposure. In certain embodiments, these reservoirs have openings that must be sealed to isolate the reservoir contents in each reservoir, to prevent leakage of material from or between any of the reservoirs. In many embodiments, hermeticity is desirable, for example to protect the purity or quality of the reservoir contents. Indeed, for most long-term in vivo applications wherein the microchip device serves as, or is included as part of, an implantable medical device, hermeticity is necessary.
U.S. Pat. No. 6,194,789 discloses a method of hermetic sealing in which an electronic or optoelectronic component is encapsulated in an adhesive and then coated with one or several metallic layers using physical vapor deposition or electroplating. It also discloses interposing multiple layers of adhesives with metallic layers to provide hermeticity and protection for the metallic layers. However, the reference neither relates to MEMS devices and hermetic micro-reservoirs nor addresses issues of biocompatibility, device interaction with drug or patient, and control of polymer deposition.
U.S. Pat. No. 3,932,227 discloses a hermetic seal formed by plating or using a physical vapor deposition technique to deposit a metal onto two inorganic substrates with a narrow gap. The gap is bridged by the deposited metal forming a hermetically sealed assembly. U.S. Pat. No. 6,474,879 discloses the same concept as specifically applied to hermetically sealing a fiber optic cable into ferrule. Again, these references do not address or relate to hermetic sealing of micro-reservoirs, biocompatibility, or device interaction with drug or patient.
U.S. Patent Application Publication 2003/0010808 describes various techniques for hermetically sealing micro-reservoirs. These techniques include high temperature laser or resistive welding, soldering, ultrasonic welding, and metal compression gaskets.
It would be desirable to provide additional or improved methods of hermetically sealing a microchip device or other reservoir devices, particularly for reservoirs containing materials sensitive to elevated temperatures.

Low temperature methods for hermetically sealing reservoir devices


Image modification using detected symmetry is described. In example implementations, an image modification module detects multiple local symmetries in an original image by discovering repeated correspondences that are each related by a transformation. The transformation can include a translation, a rotation, a reflection, a scaling, or a combination thereof. Each repeated correspondence includes three patches that are similar to one another and are respectively defined by three pixels of the original image. The image modification module generates a global symmetry of the original image by analyzing an applicability to the multiple local symmetries of multiple candidate homographies contributed by the multiple local symmetries. The image modification module associates individual pixels of the original image with a global symmetry indicator to produce a global symmetry association map. The image modification module produces a manipulated image by manipulating the original image under global symmetry constraints imposed by the global symmetry association map.

Smart phones are ubiquitous today, and every modern smart phone includes a camera feature. Most people therefore usually have a camera within arm's reach to quickly and easily take a photograph, which is referred to herein as a digital image. At the same time, people are motivated to obtain more digital images because opportunities to share them have increased, such as through sending texts and making social media posts. Consequently, more digital images are produced than ever before.
As smart phones have evolved in recent years, the camera features have provided digital images with an increasingly higher quality appearance. Nevertheless, some digital images still present an unsatisfactory appearance. For example, a portion of a desired subject of a digital image may be blurry or obscured by a foreground object. Fortunately, digital images can be modified to ameliorate an unsatisfactory visual aspect using an imaging application, such as a photo editing program.
An imaging application can modify a digital image, which is referred to herein as an image, based partially on manual direction or solely automatically. Generally, the more additional information about the image that the imaging application can obtain, the more likely an image modification can be performed automatically without manual direction. Further, additional information about the image can enable a higher quality image to result from the image modification. Additional information about an image can be intrinsic to the image or extrinsic to the image.
An example of intrinsic additional information about an image is a symmetry that is present within the image. Symmetries occur all around us. Both natural organisms, such as plants, animals, inanimate objects, and even the human body, and person-made structures exhibit symmetries in shape, texture, or form. These symmetries result in repetitive visual patterns that play a vital role in the human perception of images. Symmetric repetitions of image patterns can therefore be used as high-level constraints for an underlying image manipulation algorithm to provide some type of enhancement to an image.
To use symmetrically-repeated visual patterns to facilitate manipulation of an image, the symmetries are first discovered within the image. Unfortunately, conventional automated schemes for symmetry detection are limited to only a certain kind of symmetry or a symmetry under a certain condition, such as the absence of perspective distortion. Consequently, conventional approaches to using symmetry for image manipulation rely on human direction to specify a symmetry within the image, or conventional approaches fail to utilize each kind of symmetry that is present within the image. Thus, the former manual option thrusts tedious and repetitive work on an end-user, and the latter automated option produces visually poor results from the image manipulation.


In an approach to improve online path profiling by identifying heavy trafficked paths in streaming applications embodiments track data tuples through a streaming application. Embodiments consist of periodically executing a tuple submission application programming interface (API) and a tuple processing API. Additionally, embodiments record active paths using a profiler thread by taking snapshots of a current path index across threads. Furthermore, embodiments generate path usage information based on the recorded active path, generate a path usage graph based on the path usage information; and optimize identified trafficked paths based on the path usage data and path usage map.

The present invention relates generally to the field of streaming applications, and more particularly to profiling data paths in streaming applications.
Tuple flowing information is important for developing and tuning streaming applications. A tuple is generally a sequence of objects, whether immutable or mutable, for an interpreted, high-level, general purpose programing language. Tuples are sequences, just like lists. Creating a tuple is as simple as entering different comma-separated values. In general, flows are a set of packets which share a common property. However, the most important of such properties are the flow's endpoints. For example, the simplest type of flow is a 5-tuple, with all its packets having the same source and destination IP addresses and port numbers. Furthermore, 5-tuple flows are unidirectional (i.e., all of the 5-tuple flow packets travel in the same direction). Such 5-tuple flows are commonly referred to as microflows.
Existing tools for measuring streaming platforms include an integrated console that you can use to view the health of the instances and applications in a domain. IBM Streams is designed to address the following data processing platform objectives: parallel and high performance streams processing software platform that can scale over a range of hardware environments, automated deployment of stream processing applications on configured hardware, incremental deployment without restarting to extend stream processing applications, and secure and auditable run time environment. IBM Streams is especially powerful in environments where traditional batch or transactional systems might not be sufficient, for example: the environment must process many data streams at high rates, complex processing of the data streams is required, low latency is needed when processing the data streams. (Note: the term(s) "IBM STREAMS" and/or "STREAMS" may be subject to trademark rights in various jurisdictions throughout the world and are used here only in reference to the products or services properly denominated by the marks to the extent that such trademark rights may exist.)

Path profiling for streaming applications

International Business Machines Corporation


A flexible support structure of a seat cushion, such as a wheelchair cushion, has an upper surface with a support contour having relief areas for establishing relatively less pressure on skin adjacent to bony prominences of a user's pelvis and having a support area for establishing relatively more pressure on skin covering a tissue mass spaced from the bony prominences. A slit is formed in the rear corner of the support structure and an insertion member is inserted into the slit to change a position of the support area to thereby adjust the support contour for better support of the pelvic area. A cover encases the support structure to resist outward deformation of the support structure. The cover has an extension portion that expands the cover at the rear corner to increase a dimension of the cover to encase an increase dimension of the corner caused by the insertion of the insertion member.

A wheelchair seat cushion must perform a number of important functions. The seat cushion should be comfortable and capable of providing proper support for optimal posture and posture control for a considerable length of time. The seat cushion should also assist, or at least not materially hinder, the user in maneuvering the wheelchair, permit a useful range of motion from the pelvis and upper torso of the person, and create stability and security for the person within the wheelchair. Perhaps most importantly, the seat cushion should help prevent and reduce the incidence of pressure ulcers created by prolonged sitting on the cushion without adequate pressure relief. Pressure ulcers can become a very serious health problem for individuals who must remain constantly in contact with the support cushion, and it is important to avoid such pressure ulcers.
Wheelchair users, like everyone, are of substantially different sizes, weights and shapes. Many wheelchair users have physical disabilities and associated posture and postural control impairments such as those typically caused by congenital disorders. Other wheelchair users, such as those who have been disabled by acquired or traumatic injuries, may have a more typical size and shape. In all of these cases, the support contour of the wheelchair seat cushion must safely support the anatomy of the user, whether the anatomy is abnormal or more typical. Wheelchair seat cushions must fit and perform properly to prevent further physical impairment and pressure ulcers. The cushion must also enhance the functional capabilities of the user by supporting independence in activities of daily living. There are a number of different theories or approaches for configuring the support contour of a wheelchair seat cushion to avoid pressure ulcers and to provide adequate postural alignment.
One approach to configuring the support contour of a wheelchair seat cushion is a single generic support contour which attempts to accommodate all types of pelvic bone-structure configurations, whether more abnormal or more typical. In general, this generic approach involves using a soft, flowable or adaptable material, such as air or gel, as the support material within the wheelchair cushion. This adaptable material adjusts and redistributes in response to the weight and shape of the user to create a support contour which conforms to the anatomy of the user. By conforming to the anatomy of the user, the pressure on the skin of the user is usually distributed relatively evenly over the area of contact. The extent of the uniform pressure distribution depends on the capability of the cushion to accept and conform to the user's anatomy without displacing the adaptable material and resulting in firm contact with a support structure.
The substantially equal pressure distribution is theorized to reduce the incidence of pressure ulcers, by decreasing peak pressures on the skin in the pelvic area associated with bony prominences, most notably the ischial tuberosities, coccyx, sacrum, and greater trochanters. However, as individuals age with their disabilities, the quality of their skin is further compromised in its ability to tolerate pressure and shear forces. The decreased tolerance for pressure and shear forces, no matter how well those forces are distributed, increases the incidence of pressure ulcers.
Generic seat cushions which use flowable support material are usually incapable of providing adequate postural alignment. In general terms, adequate postural alignment is assisted by using the support contour of the seat cushion to encourage proper posture by providing a foundation for dynamic posture control. To do so, the support contour must have the capability of applying some support pressure to the pelvic area because alignment of the pelvic area is fundamental for proper posture. The adaptable support material of generic seat cushions is intended to move and redistribute itself, and consequently, is generally unstable and incapable of applying the support pressure or force in certain areas of the pelvic anatomy to optimize postural control and alignment.
Many of the disadvantages associated with generic wheelchair cushions may be overcome by using a custom wheelchair seat cushion having a support contour constructed specifically to accommodate the individual anatomical aspects of a particular user. In such cases, it is necessary to capture the anatomical shape of the individual which will contact the custom seat cushion, and then use that anatomical shape to make the custom seat cushion.
The cost of fabricating a custom wheelchair seat cushion can be substantial, for example, approximately $3000 or more. Much of the expense of a custom wheelchair seat cushion results from the amount of time consumed, and the cost of the relatively sophisticated equipment which must be used to capture and transfer the anatomical shape of the user into the support contour of the seat cushion. Moreover, despite the use of sophisticated equipment, it is nevertheless difficult to capture the anatomical shape of the user and transfer it into a customized support contour. An appreciation of some of these difficulties in creating customized wheelchair seat cushions is discussed in the above-referenced U.S. patent application Ser. No. 10/628,858.
Even if the support contour of the custom cushion is initially satisfactory to the user, changes in tissue and musculature may dictate changes in the optimal support contour of the custom seat cushion. Tissue will typically atrophy over time, particularly for first-time wheelchair users. Tissue atrophy and other tissue changes alter the pressure distribution over the support contour. Those changes may result in increased pressure on tissues surrounding the bony prominences, thereby ultimately increasing the risks of pressure ulcers. Moreover, as the muscle strength diminishes, the user relies more on the support contour of the seat to hold the proper posture. In doing so, parts of the pelvic anatomy press more directly on certain parts of the support contour as a foundation for postural alignment. The increased pressure from a change in tissue mass and postural alignment increases the pressure and shear forces on the skin in those areas, again increasing the risk of pressure ulcers.
In those types of existing wheelchair cushions having individualized support contours intended to interact with the anatomy of a specific user, slight discrepancies in capturing the shape of the individualized support may be compensated for by adding shims or other additional external support structures to the seat cushion or to a structural base upon which the cushion resides. The addition of shims or other support structures to an individualized support contour is relatively imprecise in achieving the desired effect, and requires considerable time and effort due to the number of trial fittings that are typically required. A similar situation exists with respect to anatomical changes that occur after the individualized cushion has been used for some amount of time. In both circumstances, the support capabilities of the cushion are inhibited by the trial and error approach to correcting for shape-capturing discrepancies and anatomical changes. Furthermore, the added shims and external support structures complicate the use of the cushion, because the added parts must be kept in alignment with the cushion when in use.
In those types of existing wheelchair cushions which establish an individualized or specific support contour, certain areas of the support contour may be subject to excessive deformation of the flexible support material from which the cushion is constructed. The wheelchair cushions must be constructed of material which offers some amount of flexibility or resiliency in order to function adequately as a cushion. The flexible or resilient material is subject to deformation in areas of significant curvature or areas which laterally support the anatomical structure of the user. These areas of the support contour may have generally thinner dimensions than the portions of the seat cushion directly beneath the user, or there is no support from any lateral structure to reinforce these areas because of the seat support structure beneath the cushion. Excessively flexible portions of the wheelchair cushion, or portions which may become excessively flexible through use over time, are usually not capable of providing pelvic orientation and alignment as may be required by the wheelchair user.
Because of these and other deficiencies, seat cushions with inadequate support may be used long past the time when they have become ineffective in providing proper support, either because of the cost associated with replacement of the cushion or the failure of the user to recognize the problem until pressure ulcers or other difficulties appear.
Many of the same considerations applicable to wheelchair seat cushions also apply with varying levels of criticality to other types of seat cushions used in other seating environments and applications. For example, seat cushions used in office environments are required to support the user in a comfortable manner and in a manner which encourages proper posture and without creating risks of medical problems, for example inducing blood circulatory problems.

Seat cushion with adjustable contour and method of adjusting the contour of a seat cushion


A multimedia stream is compressed in parallel by plural encoders, the compressed stream outputs of which are dynamically evaluated for merit. A best one of the compressed streams is transmitted, along with information regarding the particular compression algorithm that was used, so that the receiver's decoder can decompress the stream for presentation.

Multimedia streams, which typically include video frames, are compressed prior to transmission or storage, to conserve bandwidth. Compressing video generally means representing a relatively larger group of bits with a relatively smaller group of bits. Received compressed multimedia streams are decompressed back to their (approximate) original format for display.
It will readily be appreciated that many compression schemes are possible. More specifically, many different compression schemes, which use algorithms and/or basis functions (collectively herein, "compression algorithms"), are possible. Ordinarily two goals exist for compression. One, of course, is to compress the multimedia stream as much as possible. Competing with the first goal is the desire not to lose excessive information during the compression and expansion process. A high quality encoder, which is the name of the device typically used for compression, is configured with fixed compression algorithms that seek to optimize these two competing goals.
The present invention recognizes that depending on the nature of the particular multimedia streams to be compressed, a first compression scheme might be optimal for a first stream while a second compression scheme might be optimal for a second stream. Indeed, the compression of different parts of the same stream might be best optimized using more than a single compression scheme.
One way to handle this would be to provide an encoder that could dynamically change its compression algorithms to suit the multimedia stream currently being compressed. As understood by the present invention, however, this could require changing the compression algorithm, measuring the quality of the resulting compression, changing the algorithm again, and so on, with the candidate algorithms being tested in series. As further understood herein, while this might be acceptable for storing compressed streams, it is problematic in the context of transmission of compressed multimedia, during which sufficient time might not exist to test candidate compression algorithms in series. Having made these critical observations, the invention disclosed below has been provided.

System and method for optimizing multimedia compression using plural encoders


The AGC threshold of electric intensity level is set by the signal processor portion 107 in response to the measured result of the error rate measuring circuit 109 that measures the error rate of the received signal, and the gain control operation of the gain control circuit 106 is caused to start when the electric field intensity detected by the field intensity detector 105 reaches the threshold of electric intensity level. Accordingly, the optimum AGC threshold of electric intensity level can be set to meet the radio wave situation in which the radio receiver, i.e., the receiving situation of the received signal and also the gain control of the gain controlling means can be achieved to optimize the signal quality of the received signal in the situation of either the IM characteristic or the electric field variation characteristic, e.g., under the environment of the strong electric field IM or the environment in which the electric field is changed strongly.

1. Field of the Invention
The present invention relates to a radio receiver, a radio receiving method, and a recording medium for recording a program to execute the radio receiving method and, more particularly, a radio receiver which has an automatic gain control circuit of a step-wise gain control type in which a gain is changed by a predetermined level when a signal level of a received signal exceeds a predetermined level, a continuous gain control type in which a gain is changed in response to a signal level of a received signal, etc., a radio receiving method, and a recording medium.
2. Description of the Related Art
A radio receiver such as a pager of the day is equipped with an automatic gain control (abbreviated to "AGC" hereinafter) circuit, and then improves the intermodulation desensitization (abbreviated to "IM" hereinafter) characteristic and the characteristic due to an excessive input by controlling a gain of the radio receiver.
Here the IM will be simply explained. The "IM (intermodulation desensitization)" means such a phenomenon that, when a plurality of waves having particular frequency relationship are input into the radio receiver, noises are generated in the receiving band of the radio receiver because of distortion of semiconductor devices such as transistors, diodes, etc.
Also, as the feature of the noise generated by this IM, it is known that the noise level generated in the receiving band of the receiver becomes 1:n when the level of the interference wave having n-th order IM relationship is increased. For example, in the case that two interference waves having frequencies corresponding to the third order IM are input into the receiver, the noise level generated in the receiving band of the receiver is increased by 3 [dB] when the interference wave input is increased by 1 [dB]. In contrast, if the gain of the receiver is attenuated by 1 [dB], the desired wave is attenuated by 1 [dB] but the noise generated by the third order IM is attenuated by 3 [dB]. Therefore, a level ratio of the desired wave to the noise generated by the third order IM can be improved by 2 [dB] rather than the level before the gain is lowered by 1 [dB].
In this manner, in the IM area, desired wave to the interference wave which ensures received signal quality can be improved by controlling (attenuating) the gain of the receiver.
In the prior art, there are two type AGC circuits, i.e., a "continuous gain control type" in which a gain control amount is varied in response to the signal level input into the radio receiver, and a "step-wise gain control type" in which the gain is controlled by a previously determined constant level when the signal level exceeds a predetermined level.
First, the radio receiver having the continuous gain control type AGC circuit in the prior art will be explained with reference to FIG. 19 hereunder. FIG. 19 shows a configuration of the radio receiver having the continuous gain control type AGC circuit (first comparative example) in the prior art.
In FIG. 19, the radio receiver in the first comparative example is constructed to include an antenna 501, a low-noise signal amplifier (LNA) 502, a local oscillator circuit 503, a frequency converter circuit 504, a field intensity detector 505, and a gain control circuit 506.
The antenna 501 receives the signal transmitted from a base station (not shown). The low-noise signal amplifier (LNA) 502 amplifies the signal received via the antenna 501. The frequency converter circuit 504 executes the frequency conversion by multiplying the signal amplified by the low-noise signal amplifier 502 by a signal supplied from the local oscillator circuit 503. The field intensity detector 505 changes a voltage of an output signal GC5 in response to a signal level of the intermediate frequency signal IF after the frequency conversion. The gain control circuit 506 changes a control level of the gain in answer to the output signal GC5 from the field intensity detector 505.
If the level of the signal input into the antenna 501 is changed, the signal level of the intermediate frequency signal IF which is subjected to the frequency conversion by the frequency converter circuit 504 is also changed correspondingly. The voltage of the output signal GC5 of the field intensity detector 505 is changed according to the change in level of the intermediate frequency signal IF, and then a gain control amount of the gain control circuit 506 is changed according to such change.
Next, the radio receiver having the step-wise gain control type AGC circuit in the prior art will be explained with reference to FIG. 21 hereunder. FIG. 21 shows a configuration of the radio receiver having the step-wise gain control type automatic gain control circuit (second comparative example) in the prior art.
In FIG. 21, the radio receiver in the second comparative example is constructed to include an antenna 601, a low-noise signal amplifier (LNA) 602, a local oscillator circuit 603, a frequency converter circuit 604, a field intensity detector 605, and a gain control circuit 606.
Here the antenna 601, the low-noise signal amplifier 602, the local oscillator circuit 603, and the frequency converter circuit 604 have similar functions to those in the first comparative example (FIG. 19). The field intensity detector 605 changes the signal GC6 and outputs it when the signal level of the intermediate frequency signal IF which is subjected to the frequency conversion by the frequency converter circuit 504 exceeds a predetermined value. An operation state (ON state/OFF state) of the gain control circuit 606 is switched by the signal GC6 from the field intensity detector 605. In this case, a gain control amount controlled by the gain control circuit 606 is constant irrespective to the level of the signal input from the antenna 601.
However, in the above radio receiver in the prior art, setting of the radio receiver is decided by searching a point of compromise between the IM characteristic and the electric field variation characteristic.
First, relationships among threshold of electric field intensity level which starts AGC operation, IM characteristics, and margins of sensitivity in the AGC operation in the radio receiver having the continuous gain control type AGC circuit (first comparative example) in the prior art will be explained hereunder. FIG. 20 is a chart showing relationships among threshold of electric field intensity level which starts AGC operation, IM characteristics, and margins of sensitivity in the AGC operation in the continuous gain control type AGC circuit.
As described above, as the feature of the continuous gain control type AGC circuit, it can be listed that the gain control amount is changed pursuant to the change in signal level. However, in the case that the signal level is varied at a pitch that exceeds the follow-up speed of the AGC circuit operation against the change in the signal level, if an electric field intensity variation width of the radio signal exceeds a difference between the sensitivity level and the threshold level of starting the AGC circuit (margin of sensitivity in the AGC operation), the electric field intensity drops down below the sensible level. Therefore, the sufficient margin of sensitivity in the AGC operation must be assured.
Therefore, if the threshold of electric field intensity level which starts the AGC operation is set high, the AGC operation becomes strong against the electric field variation of the desired wave since the large margin of sensitivity in the AGC operation can be assured, but the IM area that can be improved by the AGC circuit can be reduced. Also, in order to improve the IM characteristic, if the threshold of the electric field intensity for starting the AGC operation is set at a low level, the call acceptable area is increased in the IM characteristic, nevertheless the AGC operation becomes weak against the electric field variation of the desired wave since the margin of sensitivity in the AGC operation is small. In this manner, in the continuous gain control type AGC circuit whose gain follows up the electric field variation, the threshold of the electric field intensity level which starts the AGC operation must be set with regard to both the IM characteristic and the electric field variation characteristic.
Then, relationships among the threshold of the electric field intensity level which starts AGC operation, IM characteristics, and margins of sensitivity in the AGC operation in the radio receiver having the step-wise gain control type AGC circuit (second comparative example) in the prior art will be explained hereunder.
In the step-wise gain control type AGC circuit, if the large gain is controlled at a moment, a large noise is generated in the gain control (at the time of switching). Therefore, normally the electric field detection and the gain switching are completed in the signal synchronizing portion, etc., but the gain control amount is not switched in the data interval and thus the receiving operation is carried out while fixing the gain at a constant gain control amount. Therefore, the step-wise gain control type AGC circuit cannot follow up the electric field variation in the data interval. Then, if the electric field intensity variation width of the radio signal exceeds the difference between the threshold of the electric field intensity level which startins AGC operation and the sensitivity in the AGC operation (margin of sensitivity in the AGC operation), the AGC circuit is operated under such a judgment at the time of the electric field detection that the signal level is high strong electric field. In this case, since the electric field intensity drops down below the sensible level with the AGC operation in the data interval, it is impossible to receive the transmitted data. Therefore, the sufficient margin of sensitivity in the AGC operation must also be assured in the step-wise gain control type AGC circuit.
FIG. 22 is a chart showing relationships among threshold of electric field intensity level which starts AGC operation, gain control amounts, and calling rates in the step-wise gain control type AGC circuit. In FIG. 22, the calling rate of 80 [%] is set as the sensible level.
The sensible level in the AGC operation is degraded as reduction in the gain is enhanced by increasing the gain control amount. For example, as shown in FIG. 22, such cases are considered that, if the static sensitivity is 20 [dBuV/m] when the AGC circuit is OFF (at the time of non-operation), the gain control amount is set to 10 [dB] and 15 [dB] respectively. The static sensitivity in the AGC operation is degraded by 10 [dB] and becomes 30 [dBuV/m] if the gain control amount is set small such as 10 [dB] whereas the static sensitivity in the AGC operation is degraded by 15 [dB] and becomes 35 [dBuV/m] if the gain control amount is set large such as 15 [dB]. Also, in the case that the threshold of electric field intensity level which starts AGC operation in the electrostatic field is set to 40 [dBuV/m], the margin of sensitivity in the AGC operation is 10 [dB] if the gain control amount is set to 10 [dB] whereas the margin of sensitivity in the AGC operation is 5 [dB] if the gain control amount is set to 15 [dB]. In this way, in the situation that the threshold of electric field intensity level which starts AGC operation are equal, the margin of sensitivity in the AGC operation is reduced smaller as the AGC gain control amount is set larger.
Then, FIG. 23 is a chart showing relationships among threshold of electric field intensity level which starts AGC operation, gain control amounts, and call acceptable areas in the IM characteristics in the step-wise gain control type AGC circuit.
If it is assumed that the threshold of electric field intensity level which starts AGC operation are equal, the service area existing IM interference is expanded (from AS2 to AS3) if the gain control amount is increased whereas the service area existing IM interference is contracted if the gain control amount is decreased. In this fashion, in the step-wise gain control type AGC circuit, the setting of the AGC circuit must also be set with regard to both the margin of sensitivity in the AGC operation and the IM characteristic.
As described above, regardless of the configuration of the AGC circuit, it is necessary to carry out the setting of the AGC circuit by looking for a point of compromise with regard to both the margin of sensitivity in the AGC operation and the IM characteristic.
Then, it is known that normally the sensitivity of the radio receiver is degraded much more as the transmission data speed of the transmission signal is increased more quickly. Therefore, if transmission conditions such as the transmission data speed of the signal, etc. are different, optimum values of the AGC setting values are different. However, for example, in the radio receiver for receiving the signal having the signal format whose transmission conditions such as the transmission data speed of the transmission signal, etc. are changed into two types or more during the transmission, like the FLEX system pager or FLEX-TD system pager, the same setting of the AGC circuit is applied irrespective to the transmission conditions of the signal. In other words, the optimum setting of the AGC circuit becomes different according to the radio wave situation in which the radio receiver is located. But, a means for executing the setting of the AGC circuit in response to the transmission conditions is not provided to the radio receiver in the prior art and thus it is impossible to set always the AGC circuit optimally.

Radio receiver, radio receiving method, and recording medium

Matsushita Electric Industrial Co., Ltd.


A white phosphor is provided, which is a white phosphor comprising a single material, wherein the light-emitting center is one element other than Mn, and emitting white light having excellent color rendering properties by near ultraviolet excitation. The white phosphor is represented by the formula SraSbMgcZndSieOf:Eu2+ (with the proviso that when e=1, 0<(c+d)/(a+c+d)≦0.2, 1.8≦a+c+d≦2.2, 0≦b/(b+f)≦0.07 and 3.0≦b+f≦4.4), among which, as one preferred example, the white phosphor is represented by the composition formula (SrO1-αSα)x.(Mg1-βZnβO)y.(SiO2)z:Eu2+ (in the formula, 4.5≦x/y≦27.5, 3≦z/y≦14.5, 0≦α≦0.3 and 0≦β≦0.7) is proposed.

Fluorescent tubes and incandescent light bulbs are current mainstream light sources for illumination; however, compared to a fluorescent tube or the like, those using LEDs (light-emitting diodes) for light source have less electrical power consumption, longer life span, and are safe as they are not hot to the touch, moreover, since they do not contain harmful substances such as mercury and the like, they have excellent environmental aspects, such that they are anticipated to become a mainstream light source for illumination in the near future, and a variety of research and development are being undertaken.
White light can be achieved only when lights of a variety of colors (wavelengths) are mixed. The color of an LED light, since it depends on the difference (band gap) when a high energy electron drops to a low energy position and this band gap is specific to the semiconductor crystal used in an LED chip, is fundamentally a monochromatic light such as red, green and blue, and a white light cannot be obtained from only one LED.
As a method for obtaining white light using an LED, a method has been proposed, whereby an LED serving as a light emitter and phosphor are combined, light emitted from the LED is absorbed by the phosphor, the absorbed light is wavelength-converted by this phosphor into a light having a different wavelength, white light is obtained by diffused color mixing of the light emission from the LED and the light emission from the phosphor, or, by only the light emission that has been wavelength-converted by the phosphor.
For instance, a white light-emitting device is known, in which a light-emitting diode chip (GaN), which emits blue light, and a YAG series phosphor (Y3Al5O12:Ce or the like), which emits light in yellow, are combined, a portion of the blue light radiated by the light-emitting diode chip (GaN) is left to be transmitted by the YAG series phosphor layer and the remainder is left to hit the YAG series phosphor and emit a yellow light, and these lights of two colors being color-mixed to create a pseudo-white light (refer to Patent Reference 1).
The white light-emitting device of such a constitution obtains pseudo-white light constituted by blue and yellow in terms of color components. Therefore, it has poor color rendering properties, that is to say, the property of the color of an object to be seen identically to when illuminated with natural light, and is said to be ill-suited of general illumination.
In Patent Reference 2, a light-emitting device comprising a blue LED, a green phosphor composition and a red phosphor composition is disclosed. This light-emitting device lets the light-emission (blue light) from the blue LED be received by each of the green phosphor composition and red phosphor composition, which respectively emit light with long wavelengths (green light and red light), to obtain white light by diffused color mixing of the blue light from the blue LED and the green light and red light from the phosphor compositions.
Since this light-emitting device uses a plurality of phosphors (compositions), color adjustment is difficult due to the interaction between the phosphors. In particular, as blending to adjust the contents in phosphors emitting light for each color, the mixing method and the like, is difficult, it bears the issue that variations occur in the quality of the product.
If white light could be achieved with a single phosphor, it would be useful since there would be no need to blend various phosphors, allowing the variations in the quality of the products to be suppressed. However, the few are known in prior art as white phosphors comprising a single material, the extent being that, for instance in Patent Reference 3, as a phosphor emitting red or white light by an excitation light in the near ultraviolet to visible region, a white light-emitting device is disclosed, which is a silicate of the M2SiO4 type containing Ba and Ca activated with Eu and Mn, allowing a white light-emitting to be obtained by controlling the molar ratio of Mn to a small positive value.
Patent Reference 1: JP Patent No. 3503139
Patent Reference 2: Japanese Patent Application Laid-open No. 2005-20010
Patent Reference 3: Japanese Patent Application Laid-open No. 2005-226069, in particular [0017]

White phosphor, and white light-emitting equipment or device


Smoke alarm systems, in particular for an aircraft, advantageously provide a high degree of safety so as to prevent false alarms. According to an embodiment described in this application a smoke alarm system for an aircraft is stated, comprising a camera module, a smoke warning transmitter and a housing. The camera module and the smoke warning transmitter are arranged in the housing. In jointly arranging the camera module and the smoke warning transmitter in one housing, it may become possible to arrange both sensors in one location, which can result in reduced installation expenditure and can make possible direct use of the acquisition signals for local triggering of an alarm.

1. Field of the Invention
The present invention relates to the detection of a smoke situation or a fire situation in a vehicle, for example in an aircraft. In particular, the present invention relates to a smoke alarm system for an aircraft, as well as to a method for detecting the smoke situation in a space of an aircraft.
2. Technological Background
Presently available smoke warning systems for mobile applications and correspondingly limited installation options (aircraft, railway, submarine etc.) operate with optical smoke warning transmitters. These smoke warning transmitters use the diffused-light principle with a specified alarm threshold. In the case where there is no smoke or there are no particles, the receiver does not receive a signal because there is a barrier between the light source and said receiver. However, if smoke particles (or other particles) are encountered in this region, then the light is diffused and the receiver registers a corresponding signal rise. If this signal rise exceeds a specified threshold value, the smoke warning system issues an alarm, for example an intermittent light signal at some other location, or an alarm sound.
However, in a disadvantageous way, all types of aerosols, i.e. not only smoke particles, cause light diffusion and can thus erroneously cause smoke warning transmitters to assume an alarm state. In practical application it has been shown that in such smoke warning transmitters, for example fog, dust or even the use of insecticides can cause false alarms. In most applications such false alarms pose a safety risk; in this context evacuation of aircraft or ships is pertinent.
For this reason it is advantageous to reduce, and there is a need for reducing, the probability of false alarms, which probability at times is more acute in the case of mobile applications due to quickly changing ambient conditions.


A roll stop system for a lift includes a roll stop member that is movable between a raised position and a lowered position, a driving mechanism for moving the roll stop member between the raised position and the lowered position, and a spring member acting as a buffer between the driving mechanism and the roll stop member, and preferably the spring member protects the driving mechanism from damage due to abnormal operations of the roll stop member.

1. Field of the Invention
The present invention relates generally to a lift for a vehicle, and in particular to a roll stop for the lift.
2. Description of Related Art
Lift systems are used in conjunction with vehicles to transport wheelchairs, persons, and cargo, etc. Some of these lift systems are self supporting and can be rolled or otherwise pushed against a vehicle opening. Other such systems are appended to the bottom of a vehicle chassis while others are supported at or about the sidewall of the vehicle proximate the vehicle opening. The lift systems are configured to raise and lower a wheelchair, a passenger, or cargo to and from the vehicles using a platform. The platform may be raised or lowered between the ground and the vehicle using, for example, hydraulic or electrical, actuators that provide the lifting force.
Typical lift systems are provided with certain general design components dictated principally by the need to capture and lift the wheelchair-bound passenger or cargo in a safe fashion, as well as to enable the systems to fold or be made unobtrusive when not in use, such as when the vehicle is moving.
A common lift design is a parallelogram design that uses two sets of lift arms arranged in a parallelogram or near-parallelogram arrangement on either side of the platform. Using the parallelogram keeps the lift platform in a horizontal orientation, i.e., parallel to the ground level, when the lift platform is being moved up and down.
This lift design also provides for a storage orientation enabling the platform to swing in a ninety degree arc to assume a substantially vertical orientation once the passenger or cargo is on board to enable the vehicle to proceed in a normal fashion.
The lift systems typically also include inboard and outboard roll stops on front and rear edges of the lift platform to prevent the wheelchair or cargo from inadvertently sliding off the platform during transition, and to act as ramps for loading and unloading when the platform is on the ground or level with the vehicle bed. In a typical configuration, the outboard roll stop rotates from a substantially vertical orientation to a substantially horizontal orientation acting as a ramp at ground level to enable a wheelchair to be rolled onto the platform. At the same time, the inward roll stop is at a substantially vertical orientation to prevent the wheelchair from inadvertently traveling off of the platform at its inner edge.
As the hydraulics are actuated resulting in lifting of the platform, both the outboard and inboard roll stops maintain a substantially vertical orientation, thus capturing the wheelchair or cargo on the platform. Once the platform reaches the vehicle entrance, the outboard roll stop maintains its substantially vertical orientation, while the inboard roll stop travels in an arc to act as a bridge plate between the platform and the vehicle bed.
Various mechanisms have been provided to enable the inboard roll stop to move from a blocking (vertical) orientation to a loading (horizontal) orientation simultaneously as the wheelchair reaches the vehicle opening without human intervention. Likewise, as the platform is lowered from the vehicle opening towards ground level, the roll stop actuating mechanisms can simultaneously move the inboard roll stop to a blocking orientation without input from the operator.


A catheter securement device that adheres to the skin of a patient having an epidural catheter or similar small flexible tube member inserted percutaneously, the securement device having a flexible, sheet-like main body member capable of adhering to the skin of the patient, a double notched pad member over which the catheter is bent, and a releasable retention member to secure the catheter onto the main body member.

This invention relates generally to the field of medical devices referred to as catheter securement devices, a catheter being defined herein to include a small diameter, flexible tube that is inserted through a person's skin and into a vein to deliver or remove fluids such as blood, saline solutions, medications, etc. A catheter securement device typically comprises a flexible sheet member adhesively adhered to the patient's skin, the device having means to retain the catheter tubing or a catheter housing, often a coupling or junction member for connecting one tube to another or to multiple tubes, in a relatively stable manner such that it is less likely for the catheter to be accidentally pulled from the patient.
Catheter securement devices are often located a short distance from the insertion site, such that the securement device has a minimal or reduced effect in securing the catheter tube in place at the actual insertion site. It is an object of this invention to provide a catheter securement device that reduces the likelihood of accidental dislodgement of the catheter by providing a structure that allows the securement device to be located close to or at the insertion site, the device being provided with a pair of opposing notches in a pad member for better securement of the catheter.

Double notched catheter securement assembly


A shunt pulsation trap for a positive displacement (PD) internal combustion engine (ICE) reduces pulsation, as well as noise, vibration and harshness (NVH), and the overall size of the exhaust system, and also improves cycle (fuel) efficiency. A shunt pulsation trap for a PD-ICE is configured to trap and attenuate gas pulsations before discharge to engine outlet and includes a chamber (trap volume) adjacent to the PD-ICE cavity. The chamber houses at least one pulsation dampening device, at least one relief port (trap inlet) branching off from the PD-ICE cavity into the pulsation trap chamber and a feedback region (trap outlet) communicating with the PD-ICE outlet. The associated methods of reducing pulsations are included as another aspect of the invention.

1. Field of the Invention
The present invention relates generally to the field of positive displacement (PD) type internal combustion engines (ICE), and more specifically relates to a shunt pulsation trap for improving its thermodynamic cycle efficiency and for reducing exhaust gas pulsation and induced noise, vibration and harshness (NVH) from such internal combustion engines.
2. Description of the Prior Art
An internal combustion engine (ICE), also commonly known as a piston engine is a mechanical device in which the combustion of a fuel causes the expansion of gas under high temperature and high pressure in order to move piston and generate useful mechanical work. For almost 130 years, piston type ICE have found widespread use in almost every facet of life as a power source, especially for mobile applications, such as tractors, automobiles, boats and small aircrafts, or as household power tools of lawn mowers, trimmer, etc. There are generally two types, gasoline engine (Otto Cycle) and diesel engine (Diesel Cycle) based on fuel and cycle, or 4-stroke and 2-stroke based on strokes needed for one cycle, or reciprocating and rotary based on motion. ICEs are known for high exhaust noises they generate, ranging from 100-180 dB at cylinder discharge if not silenced, well beyond the Permissible Exposure Limit of 75 dB set by National Institute for Occupational Safety and Health (NIOSH) or the 90 dB of the Occupational Safety and Health Administration (OSHA). It is becoming more and more a nuisance to the surrounding environment with people living nearby or working in office.
A PD type ICE generally converts the energy of burned gases to shaft power through either linear or rotary positive displacement movement. As classified in FIG. 2a, piston motion can be either a 4-stroke or 2-stroke fueled by either gasoline or diesel, while rotary motion is exemplified by a Wankel engine. No matter what type of motion, shape, number of strokes or fuels (which in a broader sense includes other fuels such as kitchen grease), it undergoes the same thermodynamic Otto or Diesel cycle by trapping a fixed amount of fuel and gas into a cavity, burning that gas, expanding the gas to do mechanical work and discharging the consumed gas to outlet or atmosphere. Structurally, they all have in common an intake port, a fuel delivery device, a varying volume cavity, a discharge port and valves controlling the timing of the intake and discharge release of gas mixture. FIG. 3a shows the common phases and stroke function of a conventional 4-stroke piston engine: intake, compression, combustion, expansion and discharge. FIG. 3b shows the actual Otto cycle and its ideally simplified thermodynamic process as an isobaric inlet, isentropic compression, isochoric combustion, an isentropic expansion and an isochoric plus isobaric discharge. FIG. 3c shows a typical cycle coupled with an exhaust muffling operation and FIG. 3d the generic structure of a piston 25 inside a cylinder 20 forming a cavity 37 with a discharge port 38 connected to a catalytic converter 3 and an outlet muffler 5 in series.
In operation, the inlet stroke of the IC engine sucks in the vaporized fuel mixture (or just air in a diesel engine) into the cylinder as the piston moves to the maximum volume position BDC (bottom dead center) shown as 0→1 in FIG. 3a-b, and the inlet valve closes. In compression stroke, both valves are closed and the piston starts its movement to the minimum volume position known as TDC (top dead center) and compresses the fuel mixture. During this approximated isentropic process as shown by 1→2 in cycle diagram, the pressure, temperature and density of the fuel mixture all increase. It is immediately followed by an almost instantaneous combustion simplified as an isochoric process 2→3, as the fuel mixture burns. The increased high pressure exerts a greater amount of force on the piston and pushes it towards the BDC. Expansion of working fluid takes place isentropically from 3→4 and work is done by the system that is transmitted to the crank shaft. At the end of the power stroke the exhaust valve suddenly opens, releasing heat and some gas instantly as shown as a constant volume or isochoric process from 4→1. The exhaust stroke follows when piston starts its movement from BDC to TCD or 1→0, exhausting the rest of gas mixtures from the cylinder. At the end of this stroke, the exhaust valve closes, the inlet valve opens, and the sequence repeats in the next cycle.
4-stroke ICEs require two revolutions for a complete cycle while 2-stroke engines only need one revolution to complete the almost same process as described above. Many petrol and gas engines work on a cycle which is a slight modification of the Otto cycle such as Diesel cycle that uses a compression heating ignition rather than a separate ignition system. This variation allows diesel fuel be injected directly into the cylinder so that combustion occurs at constant pressure, instead of a constant volume as in Otto cycle. Another variation is called Atkinson and Miller cycle that has an asymmetrical compression and expansion strokes by using variable valve timing so that it operates more fuel efficiently.
In essence, all PD engines divide the continuous inlet gas stream mechanically into parcels of cavity size that is then disposed discretely to the exhaust after the work is done. This process inherently generates gas pulsations with a low frequency, often called cylinder firing rate, which is equal to discharge valve opening frequency or RPM/60 for a 2-stroke and RPM/120 for a 4-stroke ICE. On the other hand, the discharge pulsation is very significant if the cavity gas pressure is higher than the discharge exhaust pressure at the moment the discharge valve opens. It is this pressure difference at the discharge opening that is responsible for generating large amplitude pulsations which in turn excite noises and vibration of the entire engine system. The pulsations generated by the pressure difference at sudden discharge valve opening are periodical pressure spikes as high as 100-180 dB which could cause downstream mechanical damages and high noise if not properly controlled. Most often, pulsations are confined within the exhaust system and could result in fatigue failures of downstream components such as cylinder head, exhaust manifold, catalytic converter and exhaust muffler, or the turbocharger if equipped.
The muffler is now often required at the engine exhaust in order to control the exhaust pulsation and noises. The most common muffler type is reactive or sometimes absorptive or a combination of both is used too. This serially connected muffler or silencer is generally very effective in pulsation and noise control, reducing noise level (sound pressure level) by as much as 20-55 dB, but it suffers a fair amount of pressure losses at the same time. In principle for a serial muffler, more effective noise attenuation is always at the expense of higher pressure loss. Sometimes pressure loss can be as high as 2-4 psi under high load conditions. The loss of pressure or the increased exhaust back pressure reduces engine mechanical power output hence affecting its fuel efficiency. It is one of the contributing factors that results in low engine efficiency today, just 20-30%. An example for this trade-off is found on some performance vehicles such as race cars that used to replace a higher-attenuating-higher-loss reactive type muffler with a less-attenuating-less-loss absorptive type muffler. But the ever stringent regulations from the government and growing public awareness of the global warming and comfort level in residential and office areas have reversed that practice and given rise to an urgent need for both quieter and more efficient internal combustion engines as exemplified by new emission standards as CARB (California Air Resources Board).
The present invention tries to meet these environmental needs and tackle the problems at the source of loss and noise from a different perspective. The underlining theory is based on a postulation that large amplitude waves and instantaneous flows induced by pressure difference at the moment of exhaust valve opening are the primary cause of discharge pulsations and noises. This theory is analogous to a well studied physical phenomenon as occurs in a shock tube (invented in 1899) where a diaphragm separating a region of high-pressure gas from a region of low-pressure gas inside a closed tube suddenly burst open. As shown in FIGS. 1a-1b, when the diaphragm is suddenly broke open, a series of expansion waves is generated propagating from the low-pressure to the high-pressure region at the speed of sound, and simultaneously a series of pressure waves which can quickly coalesces into a shockwave is propagating from the high-pressure to the low-pressure region at a speed faster than the speed of sound, and inducing rapid fluid flow behind the wave front. An interface, also referred to as the contact surface that separates low and high pressure gases, follows at the same fluid velocity after the pressure waves or the shock wave.
To understand pulsation generation mechanism in light of the shock tube theory, let's review a cycle of a classical 4-stroke engine as illustrated in FIGS. 3a-3d by following one flow cavity from inlet to exhaust. First the vaporized fuel and air mixture enters into the cavity formed by a piston and a cylinder as inlet valve opens and closes. After the cavity is closed to both the inlet and outlet, the trapped gas is then being compressed, ignited and expanded, driving the piston doing mechanical work. When a desired expansion ratio is reached, the cavity is suddenly opened to the outlet and discharged. A serially connected discharge muffler is there to attenuate pulsation and noise generated at the exhaust opening.
In general, the cavity pressure of an ICE is higher than the outlet pressure as exhaust gas needs to get out of the cavity. This results in a forward flow rushing out of the cavity to equalize the outlet pressure as soon as the cavity is opened to the discharge according to the conventional theory. Since this happens almost instantaneously and there is almost no volume change for the cavity, the expansion is regarded as a constant volume process, or isochoric process as shown as 4→1 in FIGS. 3a-3b. However, according to the shock tube theory, the discharge valve opening at point 4 as shown in FIGS. 3a-3b, resembling the diaphragm bursting of a shock tube as shown in FIG. 1b, would generate a series of expansion waves into the cavity. The fan of expansion waves would sweep through the high pressure gas inside the cavity and expand it at the same time at the speed of sound. This results in an almost instantaneous adiabatic expansion because wave travels much faster than the fluid particle or piston. In this view, the wave induced expansion is the primary driver for pressure equalization process from 4→1 and this process is adiabatic in principle other than the conventionally assumed isochoric.
In view of the new theory to explain the pulsation generation mechanism, as the expansion waves travel to high pressure cavity as shown in FIG. 3d, simultaneously generated pressure waves or a shock wave front travel in the opposite direction causing rapid pressure increase and inducing forward flow down-stream. This shock wave travelling downstream at a speed faster than the speed of sound and inducing a fast flow behind is the dominant source of discharge pulsation and noise for a positive displacement internal combustion engine. Any effective pulsation and noise control should target this high velocity large amplitude mixture of waves and induced flow while minimizing the main flow losses at the same time.
Since the amplitude of gas pulsation in ICE is typically much higher than the upper limit of 140 dB set in the classical acoustics, the small disturbance assumption or the resulting linear wave equation is often inadequate to predict its behavior. Instead, the following rules can be used for large disturbances when the SPL is beyond 140 dB. These rules are based on the above discussed Shock Tube theory and can be used to judge the source of gas pulsation and quantitatively predict its amplitude and travel directions. In principle, these rules are applicable to different gases and for gas pulsations generated by any industrial PD type gas machinery or devices such as engines, expanders, or pressure compressors, vacuum pumps and valves.                1. Rule I: For two divided compartments (either moving or stationery) with different gas pressures p4 and p1 (FIG. 1a), there will be no or little gas pulsations generated if the two compartments stay divided;        2. Rule II: If the divider between the high pressure gas p4 and the low pressure gas p1 is suddenly removed (FIG. 1b), gas pulsations are generated at the location and moment of the opening as a composition of a fan of Pressure Waves (PW) or a quasi-shock wave, a fan of Expansion Waves (EW) and an Induced Fluid Flow (IFF) with magnitudes as follows:PW=p2−p1  (1)EW=p3−p2  (2)ΔU=(p2−p1)/(p1×W)  (3)Where ρ1 is the gas density at low pressure region, W the speed of the lead pressure wave, ΔU the velocity of Induced Fluid Flow (IFF);
3. Rule III: Pulsation PW is the action by the high pressure gas p3 to the low pressure gas p1 while pulsation EW is the reaction by the low pressure gas p1 to the high pressure gas p3 in the opposite direction, and their magnitudes are such that they equally divide the initial pressure ratio p3/p1 [equation (4): p2/p1=p3/p2=(p3/p1)1/2]. At the same time, both PW and EW pulsations induce a unidirectional fluid flow pulsation IFF in the same direction as the PW.
Rule I implies that there would be no or little pulsations during compression (expansion) and combustion phases of a ICE cycle because of the absence of either a pressure difference or sudden opening. The focus instead should be placed upon the intake and exhaust phases, especially at the moment of the intake and discharge when it is suddenly opened and when there is a pressure difference at the opening.
Rule II indicates specifically the moment of pulsation generation as the instant the divider separating p3 and p1 opens and the location as the divider. Moreover, it defines two sufficient conditions for gas pulsation generation:
a) The existence of a pressure difference Δp31;
b) The sudden opening of the divider separating that pressure difference.
Because all PD gas machinery converts energy between shaft and fluid by dividing incoming continuous fluid stream into parcels of cavity size and then discharging each cavity separately at the end of each cycle, there always exists a "sudden" opening at discharge phase to return the discrete parcels back to a continuous stream again. So both sufficient conditions are satisfied at the moment of discharge opening if there exists a pressure difference between the cavity and outlet it is opened to. For ICE, this pressure difference is always existing as ΔP41 as shown in P-V diagram of FIG. 3. In addition to the pressure difference induced pulsation, there co-exists a hardware (like a valve) induced flow pulsation too, but its magnitude is typically much smaller for most existing fluid machinery, and is roughly proportional to its equivalent velocity pressure. FIG. 2b shows graphically the relationship between the initial unbalanced pressures and the summation of resulting gas pulsations.
Rule II also reveals the composition and magnitudes of gas pulsations as a combination of large amplitude Pressure Waves (PW) or a quasi-shockwave, a fan of Expansion Waves (EW) and an Induced Fluid Flow (ΔU). These waves are non-linear waves with changing wave form during propagation. This is in direct contrast to the acoustic waves that are linear and wave fronts stay the same and do not induce a mean through flow. It is interesting to note the wholeness of three different pulsations (PW, EW and IFF) that are generated simultaneously and one cannot be produced without the others. This makes gas pulsations very difficult to control because it's not one but all three effects have to be dealt with.
Rule III shows further the interactions between two gases of different pressures are mutual so that for every PW pulsation, there is always an equal but opposite EW pulsation in terms of pressure ratio (p2/p1=P3/p2). Together, they induce a unidirectional fluid flow pulsation (IFF) in the same direction as the pressure waves (PW).
It should also be emphasized the drastic difference on magnitude and behavior between acoustic waves and pulsations discussed above. First of all, the linear acoustics is limited to pressure fluctuation levels below 140 dB, equivalent to pressure below 0.002 Bar or 0.03 psi. For industrial type fluid machinery, the measured pressure fluctuation or pulsation is often in the range of 0.3-30 psi (or even higher), equivalent to 160-200 dB according to the SPL definition. So the pulsation pressures inside the industrial fluid machines are much higher and well beyond the pressure range intended in the Classical Acoustics. Physically, the acoustic waves are sound waves travelling at the speed of sound with no macro fluid movement with it while pulsations are a mixture of strong pressure and expansion waves that also induce an equally strong macro fluid flow travelling with speeds from a few centimeters per second up to 1.89 times of the speed of sound (Mach Number=1.89), for example. It is this large pressure forces and induced high velocity fluid flow that could directly damage a system and components on its travelling path, in addition to exciting vibrations and noises. With the above proposed Pulsation Rules, it is hoped that more realistic pulsation prediction is made possible so that the true nature of pulsations can be realized, hence controlled.
Accordingly, it is always desirable to provide a new design and construction of a PD type ICE that achieves high pulsation and NVH reduction at source, improves fuel efficiency and eliminates the discharge muffler at the same time.

Shunt pulsation trap for positive displacement (PD) internal combustion engines (ICE)


A levelling valve is provided for automatically keeping constant the vehicle height of a commercial vehicle with air suspension. The levelling valve comprises a spring loaded double valve body (17), an inlet seat (18), a hollow control rod (20) having an outlet seat (19) for the double valve body (17) and movable toward sealed engagement with the double valve body (17), an actuation drive (6) having a guiding member (27) and an eccentric follower (10) responsive to the change in vehicle height for moving the control rod (20) towards or away from sealing engagement with the double valve body (17). A first vehicle height according to a closing position may be controlled by the actuation drive (6). A control piston (28) is located in a control chamber (31) in alignment with the axis (3) of the control rod (20) and is provided for the attainment for setting of a second vehicle height. The control chamber (31) is located in the guiding member (27) of the actuation drive (6). The control piston (28) is slidingly and sealingly arranged in the guiding member (27) so that the eccentric follower (10) is not loaded by a force acting on the control piston (28) during the adjusted second vehicle height. The control rod (20) is supported on the control piston (28).

A levelling valve of the type described above is known from German Patent Application No. DE 37 16 436 Al, the levelling valve having a height limitation. A control rod acting upon a double valve body of the inlet valve and the outlet valve is connected with a guiding member arranged slidingly and sealingly in a housing. The guiding member comprises a groove cooperating with an eccentric follower of an actuation drive. The actuation drive comprises a lever, a shaft rotatably arranged, and the eccentric follower. For height limitation purposes a hollow actuation rod is connected with the guiding member on the side opposed to the double valve body. The hollow actuation rod carries a vent seat to which an annular valve body is assigned, the valve body being spring loaded and suspended in the housing. The valve body cooperates with an inlet seat located in fixed relation there to in the housing so that in this way a closing valve is generated for a conduit leading to the bellows. Thus, the maximun suspension height of the vehicle is defined and limited. There is an assignment to the angle position of the lever of the actuation drive caused by the closing position, i.e. the position in which both the inlet valve and the outlet valve are closed at the same time. In general, a horizontal position of the lever of the actuation drive is assigned to the mentioned closing position in accordance with a first vehicle height. This means that the chassis of the vehicle during driving takes a first determined height in which the lever of the actuation drive is in a horizontal position and the closing position is reached on the inlet valve and the outlet valve so that the suspension bellows are neither aerated nor vented, but carry the chassis in the designed height. However, often it is useful to be able to attain a second vehicle height differing from the first vehicle height. This may be the case in order to adapt an inclined position of semitrailer to points on tractors having different heights. Another possibility of a second vehicle height is useful for busses. In such a second vehicle height the chassis of the bus may be lowered to make the entering of the bus easy for persons. In a third application it may be useful to have the chassis lowered to generate reduced drag. A levelling valve is known from FIG. 4 of DE 37 16 436 Al having the possibility to adjust alternatively to two different vehicle heights. For these purposes the groove in the guiding member into which the eccentric follower extends is provided with a large clearance so that the eccentric follower contacts the groove once on the one side of the groove or on the other side of the groove respectively. By this clearance the two different vehicle heights are defined. A control piston is connected in fixed manner with the guiding member and with the actuation rod extending downwardly in order to adjust alternatively to one of the two different vehicle heights. An aeratable control chamber is assigned to the control piston, the control chamber being positioned in the housing of the levelling valve. The aerated position of the control chamber is assigned to the second vehicle height, while the first vehicle height is reached by springs loading the control rod in case the control chamber is vented. It is a disadvantage that the control piston during aeration of the control chamber loads the guiding member and thus the control drive. Especially the eccentric follower extending into the groove of the guiding member is subjected to substantial wear reducing lifetime of the levelling valve. A further disadvantage is the different acting of the height limitation with respect to the first or the second adjusted vehicle height. If the second vehicle height is located above the first vehicle height the maximal stroke up to the stops for the chassis via the bellows must be assigned to the second vehicle height. However in this case the height limitation during adjustment of the first vehicle height is active i.e. the maximum stroke of the bellows cannot be used in the position of the first vehicle height.
German Patent No. DE 23 18 535 describes a levelling valve of a different type, in which the shaft of the actuation drive is extended and further elements are provided in parallel to the control rod for the inlet valve and the outlet valve, for example a second outlet valve having an enlarged cross section. Levelling valve of this kind may be provided with a height limitation also. On the other hand the adjustment of a second vehicle height is possible. The alternative adjustment of two different vehicle heights is described as a variation of a starting point or position. This variation of the starting position is performed in a similar manner as illustrated in FIG. 4 of DE 37 16 436 by the fact of providing a large clearance between the eccentric follower and the groove in the guiding member, which is bridged in the alternative adjustment of the two different vehicle heights.

Levelling valve for automatically keeping constant the vehicle height of a commercial vehicle with air suspension


An optical router capable of efficiently allocating optimum optical paths to optical signals at optimum timings is provided in accordance with the present invention. The optical router is capable of delaying a plurality of the optical signals containing routing information attached to the header parts thereof. The optical router contains an optical switch which has a plurality of input and output ports; an optical-electrical converter for converting a plurality of the optical signals to electrical signals; memory wherein path control information and delay time information are stored; and a controller for generating an electrical routing control signal which can change the optical path of the optical signals by finding the path control information according to the routing information extracted from the output of the optical-electrical converter and which can delay the electrical routing control.

1. Field of the Invention
The present invention relates to an optical router which is disposed on an optical node basis, selects optical paths for optical signals transmitting them through such optical transmission lines as optical fibers, and outputs the optical signals through the optical paths, whereby an optical communications network is formed. More specifically, the present invention relates to an optical router capable of efficiently allocating optimum optical paths to the optical signals at optimum timings.
2. Description of the Prior Art
An optical router is disposed on an optical node basis, selects the optical path of an optical signal transmitting it through such an optical transmission line as an optical fiber, and outputs the optical signal through the optical path, whereby an optical communications network is formed. Publications on the prior art related to optical routers include the following:                Japanese Laid-open Patent Application 1996-163610        Japanese Laid-open Patent Application 1996-204675        Japanese Laid-open Patent Application 2001-255567        Japanese Laid-open Patent Application 2001-255084        Japanese Laid-open Patent Application 2002-164847        "Photonic Network Revolution  Technologies for realizing the world's most advanced information technology nation": published by the Secretariat, Photonic Internet Forum, within The Support Center for Advanced Telecommunications Technology Research, Foundation (January 2002): 95–98
FIG. 1 is a block diagram illustrating an example of such a conventional optical router as mentioned above, where the example is identical to the optical router described in the patent application 2002-284970 filed by the applicant of the application concerned.
The patent application 2002-284970 filed by the applicant of the application concerned illustrates an example of an optical router wherein an optical signal (optical packet signal) being transmitted is split into a header part and a data part, and routing information, such as a destination address, is added to the header part according to the routing information, thereby permitting a selection to be made from given optical paths.
FIG. 1 indicates optical delay means 1 for delaying optical input signals by desired lengths of time by circulating (transmitting) the signals through a fiber-optic optical loop as many times as desired, an optical-electrical converter 2, such as a photodiode or phototransistor, optical switch 3 provided with three input ports and three output ports, controller 4 for controlling optical path selection made by optical switch 3; and memory 5 wherein path control information, such as routing tables, is stored. In addition, optical delay means 1, optical-electrical converter 2, optical switch 3, controller 4 and memory 5 compose optical router 50.
In FIG. 1, the three optical input signals indicated by SG01 are input to the three input ends of optical delay means 1, as well as to the three input ends of optical-electrical converter 2.
Optical output signals from the three output ends of optical delay means 1 are input to the three input ports of optical switch 3, and the three optical output signals indicated by SG02 in FIG. 1 are output from the three output ports of optical switch 5.
The electrical output signal of optical-electrical converter 2 is coupled with controller 4, and the electrical delay control signal of controller 4 and the electrical routing control signal thereof indicated by SS01 are coupled with the control terminals of optical delay means 1 and optical switch 3. In addition, the electrical input-output signal of controller 4 is mutually coupled with memory 5.
Now the behavior of the example of the prior art optical router illustrated in FIG. 1 is described by referring to FIG. 2. FIG. 2 is a schematic view illustrating a specific example of optical delay means 1 and indicates an optical switch 6 and optical fiber 7 composing the optical loop.
The optical input signals indicated by SG01 in FIG. 1, which contain routing information, such as destination addresses, added to the header parts thereof, are delayed at optical delay means 1 by desired lengths of time just long enough for controller 4 or any other element to process electrical signals.
For example, optical switch 6 is controlled so that the path of an optical input signal is changed, the signal is entered to the optical loop comprised of optical fiber 7, and the optical input signal is transmitted while being circulated as indicated by RP11 in FIG. 2. If optical switch 6 is controlled under this condition so that the optical input signal is confined within the optical loop, a delay time, which is as long as the duration required for the signal to circulate (transmit) through optical fiber 7, occurs.
Consequently, by circulating (transmitting) the optical input signal through the optical loop as many times as desired and controlling optical switch 6 to let the signal out of the optical loop so that the delay time is properly adjusted, it is possible to delay the optical input signal by lengths of time just long enough for controller 4 or any other element to process electrical signals.
Concurrently, the optical input signals indicated by SG01 in FIG. 1, which contain routing information, such as destination addresses, added to the header parts thereof, are converted to electrical signals at optical-electrical converter 2 and input to controller 4.
Controller 4 extracts the routing information from the electrical signal being input from optical-electrical converter 2, finds path control information stored in memory 5 according to the routing information, specifies a subsequent-stage optical router (output port) appropriate for the entered optical signals to transmit the signal to the destination through the shortest path, and accordingly selects from the optical paths of optical switch 3 by outputting the electrical routing control signal indicated by SS01 in FIG. 1.
For example, controller 4 controls optical switch 3 so that an optical path is selected in such a manner that an optical input signal is input to the input port of optical switch 5 indicated by PT01 in FIG. 1, and is output from the output port of optical switch 3 indicated by PT02.
If such an optical input signal as is properly delayed by optical delay means 1 after the completion of such optical path selection as described above is input to the input port of optical switch 3 indicated by PT01, the optical output signal will be output from the output port indicated by PT02.
This means that by adding routing information, such as a destination address, to the header part of an optical signal, it is possible to make optical path selections according to the routing information.
Furthermore, since it is possible for optical delay means 1 to delay the optical input signals by desired lengths of time just long enough for controller 4 or any other element to process electrical signals, it is also possible to cope with such problems as the occurrence of large delay times resulting from the failure to transfer the optical input signals (optical packets).
However, since the example of the prior art optical router is configured so that the optical input signals are circulated (transmitted) through the optical loop comprised of optical fiber 7 as many times as desired using optical delay means 1 and optical switch 6 is controlled to let the signals out of the optical loop so that the delay time is properly adjusted, the delay time has discrete values.
Let us take FIG. 3, which is a timing diagram illustrating the way delay times are produced by optical delay means 1, as an example. In FIG. 3, optical signal (no delay) (a) delays changing optical signal (one-turn delay) (b), optical signal (two-turn delay) (c), optical signal (three-turn delay) (d) and optical signal (four-turn delay) (e) step by step, as the number of circulations (turns) at the optical loop comprised of optical fiber 7 increases to one circulation (turn), two circulations (turns), three circulations (turns) and four circulations (turns).
More specifically, a delay time indicated by TD21 in FIG. 3 is produced in the first turn, a delay time indicated by TD22 is produced in the second turn, a delay time indicated by TD23 is produced in the third turn, and a delay time indicated by TD24 is produced in the fourth turn. This means that a total delay time of "TD21+TD22+TD23+TD24" is produced as the result of making four turns.
Note that the delay time produced by a single turn is kept constant if the ambient environmental conditions (temperature, etc.) of optical fiber 7 composing the optical loop remain unchanged, and the following equation holds true:TD21=TD22=TD23=TD24  (1)
For this reason, a delay time produced by optical delay means 1 equals an integer multiple of TD21 (number of circulations or turns), resulting in a discrete value.
On the other hand, the length of time just enough for controller 4 or any other element to process electrical signals greatly varies depending on whether or not forwarding error correction processing (hereinafter simply referred to as FEC processing) is applied. The length of time also varies greatly depending on the algorithm used even when FEC processing is applied.
Note however that as discussed earlier, the delay time resolution of optical delay means 1 is TD21 shown in FIG. 3. It is therefore not possible to fine-tune the delay time in increments smaller than TD21.
Let us take FIG. 4 as an example, which is a timing diagram illustrating the relationship between optical signals and an electrical routing control signal. FIG. 4 shows optical signal (no delay) (a), optical signal (one-turn delay) (b) whose number of circulations (turns) at the optical loop comprised of optical fiber 7 is one, and optical signal (two-turn delay) (c) whose number of circulations (turns) is two.
In FIG. 4, the time length indicated by PT31 in electrical routing control signal (d) is just long enough for controller 4 or any other element to process electrical signals. In order to secure such a time length, the optical signal in question must be delayed at optical delay means 1 by letting the signal undergo at least two circulations (turns), rather than one circulation (turn).
In this case, a dead time indicated by WT31 in FIG. 4 occurs during the time interval from when the required processing of electrical signals is completed at controller 4 or any other element within the time length indicated by PT31, to when controller 4 selects from the optical paths of optical switch 3 and the optical signal is delayed by TD21+TD22 before being allowed to enter optical switch 3.
This means that the optical paths of optical switch 3 are occupied during the time length indicated by WT31 in FIG. 4 even though none of the optical paths is used (no optical signals are transmitted). Consequently, the prior art optical router has had the problem that it is not possible to efficiently allocate optimum optical paths to optical signals (optical packets) at optimum timings.
Since the delay time indicated by TD21 in FIG. 4, for example, is extended in cases where the optical loop of optical delay means 1 is relatively long, the dead time indicated by WT31 is likely to increase further.


A method of fabricating a thermoelectric device includes providing a substrate having a plurality of inclined growth surfaces protruding from a surface thereof. Respective thermoelectric material layers are grown on the inclined growth surfaces, and the respective thermoelectric material layers coalesce to collectively define a continuous thermoelectric film. A surface of the thermoelectric film opposite the surface of the substrate may be substantially planar, and a crystallographic orientation of the thermoelectric film may be tilted at an angle of about 45 degrees or less relative to a direction along a thickness thereof. Related devices and fabrication methods are also discussed.

Thermoelectric materials may be used to provide cooling and/or power generation according to the Peltier effect. Application of solid state thermoelectric cooling may be expected to improve the performance of electronics, photonics and sensors such as, for example, RF receiver front-ends, processors, programmable gate arrays, infrared (IR) imagers, laser diodes, light-emitting diodes, ultra-sensitive magnetic signature sensors, and/or superconducting electronics.
Traditional thermoelectric devices may be fabricated by assembling arrays of P and N thermoelectric elements (TE), as shown in perspective and cross-sectional views in FIGS. 27A and 27B, respectively. The TEs may be soldered to top and bottom high thermal conductivity substrates or headers. The headers may be oriented parallel to each other and may "sandwich" the TEs. Electrically conductive traces may be formed on the top and bottom headers and may form a series electrical circuit with alternating P and N elements. In this structure, the electrical current in the TEs and the flow of heat through the elements may both be substantially normal to the orientation of the headers, as shown in FIG. 27B.
The performance of a thermoelectric device may be a function of the figure(s)-of-merit (ZT) of the thermoelectric material(s) used in the device, with the figure-of-merit being given by:ZT=(α2Tσ/KT),  (equation 1)where α, T, σ, KT are the Seebeck coefficient, absolute temperature, electrical conductivity, and total thermal conductivity, respectively. The material-coefficient Z can be expressed in terms of lattice thermal conductivity (KL), electronic thermal conductivity (Ke) and carrier mobility (μ), for a given carrier density (d) and the corresponding α, yielding equation (2) below:Z=α2σ/(KL+Ke)=α2/[KL/(μdq)+L0T)],  (equation 2)where, L0 is the Lorenz number. State-of-the-art thermoelectric devices may use alloys, such as p-BixSb2-xTe3-ySey (x≈0.5, y≈0.12) and n-Bi2(SeyTe1-y)3 (y≈0.05) for the 200 degree K to 400 degree K temperature range. For certain alloys, KL may be reduced more strongly than μ leading to enhanced ZT. Also, DTmax (or ΔTmax) is another figure of merit for thermoelectric modules, and can be defined as the maximum operating temperature difference between the higher temperature side ("hot" side) and lower temperature side ("cold" side) of the thermoelectric film when no heat load is applied. An optimal current (Imax) is applied to achieve this maximum cooling. DTmax is defined with the hot (heat rejection) side held at a fixed temperature. When the heat load is increased from zero, the operating temperature difference, ΔT, is reduced. The ΔT is reduced to zero at a specific heat load, referred to as Qmax, which is quantified in watts. This is the maximum amount of heat that can be pumped by the thermoelectric device at a given temperature. Maximum heat pumping density is the Qmax per unit area of the device (Qmax/A).
In bulk thermoelectric materials, the c-axis of the crystal may have a high degree of tilt, such that, when thermoelectric modules are fabricated from the bulk materials, the heat/electrical conduction path may be substantially aligned with the direction of lowest resistivity in the bulk material. However, thinning of high tilt bulk material can be difficult, as the material is typically not durable enough to withstand the thinning process for thicknesses less than about 100 μm.
Controlled growth of thin-film thermoelectric materials has been developed. For example, V-VI based films, such as bismuth telluride (Bi2Te3) and/or antimony telluride (Sb2Te3)-based epitaxial films grown on gallium arsenide (GaAs) substrates, may be used in the fabrication of thin-film thermoelectrics. For thin film processes, the c-axis of the crystal is typically grown with a nearly 0 degree angle with respect to a perpendicular to the growth surface. As such, when thermoelectric modules are fabricated from thin-film thermoelectric materials, the heat/electrical conduction path may be substantially normal or perpendicular to the substrate growth surface, and substantially parallel to the growth direction. Some tilt in the c-axis of the thermoelectric film can be introduced by using an epitaxial growth process (such as metal-organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE)) and providing an offcut substrate surface, as described, for example, in commonly-owned U.S. Pat. No. 7,804,019 to Pierce et al.

Thin film thermoelectric devices having favorable crystal tilt