A system for switching video of two different standards that uses a single crosspoint matrix and a single local controller coupled to two memory blocks for storage of crosspoint selection data. The crosspoint selection data is written to the crosspoint matrix according to the video reference signals that correspond to the crosspoint selection data to be written. Switching of the crosspoints then occurs according to the video reference signal corresponding to the crosspoints to be switched.

The present invention relates to switching video signals, and more particularly to switching video of two different standards.
Some users of a video matrix find it desirable to be able to switch video of two different standards, i.e. the Phase Alternate Line standard (PAL), which is a 50 Hz/625 line standard, and the National Television System Committee standard (NTSC), which is a 60 Hz/525 line standard. For example, a video production house that works with international customers may be dealing with different video standards. Or, the user may wish to switch video of the same standards, but with different timings.
The problem arises in that communication from a local controller is referenced to a vertical interval strobe, say VI1, created from a single system reference, say Reference 1, by a vertical interval (VI) pulse generator. Control of the matrix by a local controller works in the following way. Reference 1 may be either the 50 Hz or 60 Hz standard, and is typically a color black signal. The pulse of VI1 typically occurs during the middle of line 10 for 60 Hz systems, or the middle of line 6 for 50 Hz systems. Communications are sent to a crosspoint switch while VI1 is not pulsing, and the final strobing, or setting of the switch takes place when the pulse occurs. If all inputs are timed to the system reference, all switches occur at the correct time. However, if the user wishes to have sources that are of a different reference than Reference 1, say Reference 2, there needs to be a way to ensure that the video switches during the correct line for sources referenced to Reference 2, even though communications still occur according to Reference 1.
There are currently two methods of dealing with this problem. The first, as shown in FIG. 1, is to simply switch signals of a second standard according to the first and allow them to glitch, but this is not acceptable. The second, as shown in FIG. 2, is to have two separate matrices, each with its own local controller, vertical interval pulse generator and reference. Often times, however, the user will have a large portion of his or her system switching one standard, while only a few sources are of the other standard. This makes it unattractive to have a separate matrix with its own local control.
What is desired is a system for switching video of two different standards that allows a single controller to still write crosspoint data at a rate according to a first reference, but allows switching to occur at the vertical interval of the first reference or a second reference of a same or different standard.

System of switching video of two different standards


A communication system can utilize a STANAG 5066 profile and include a data rate link mechanism. The data rate link mechanism can reside in a linking layer, such as, a subnetwork management sublayer according to the STANAG 5066 application. The mechanism allows data rate change functions of HF messages to increase throughput upon link establishment. Link quality can be determined by LQA signals generated according to MIL-STD-188-141B profiles.

Communication systems generally include transmitters and receivers which must negotiate a data rate at which encoded data is transferred. The encoded data can be digital or analog data. Typically, the transmitter provides data at a first data rate and increases or decreases the data rate in response to errors associated with the communicated data. The receiver analyzes the received data according to a number of error detection schemes and requests that the data rate be increased or decreased depending upon the number of errors detected.
According to a conventional high frequency (HF) data communication system defined by Standard Agreement 5066 (STANAG 5066 V1.2), communication between the communication units begins at an initial or default data rate. The default data rate is defined in Paragraph C.6.4.1 of STANAG 5066. In addition, an initial or default interleaving level for STANAG 5066 systems is defined in Paragraph C.6.4.1. Paragraph C.6.4.1 of STANAG 5066 states:                All connections on which the data rate or other modem parameters can be controlled shall be initiated at 300 bits per second using short interleaving.
Therefore, communication systems operating according to STANAG 5066 utilize a relatively low initial data rate and a low throughput interleaving level. For example, a first communication unit operating according to STANAG 5066 provides data at a relatively low data rate (300 bits per second (BPS)) using short interleaving to establish a first leg of communication. The use of relatively low data rate with short interleaving ensures that initial communications are not error prone.
Using this relatively low data rate with short interleaving severely limits the amount of data which can be transferred upon the initial establishment of the link. Thereafter, increased data rates and other interleaving schemes can be negotiated based upon the quality of the channel between the first and second communication units. For example, if the initial communication leg is communicated without any errors, the data rate and the interleaving parameters can be increased to achieve a higher overall transfer rate of data according to paragraph C.1.4 of STANAG 5066. However, this technique requires additional time before information is communicated at its optimal rate.
Thus, there is a need for an initial adaptive data rate algorithm which does not rely on low initial data rate. Further, there is a need for an initial adaptive data rate algorithm which does not rely on a relatively short interleaving parameter. Further still, there is a need for increased throughput between communication units during initial communication.

Adaptive data rate link mechanism for high frequency data communication


A wireless communication network with improved performance and a method and controller for controlling data rate in the network are provided. The invention provides a feedforward approach to data rate control in wireless networks. The invention is based on designing an optimal, but non-causal, controller and its subsequent “causification,” which results in a practical, implementable controller, driven by an estimate of the bit error probability. This controller leads to a minimum 5%-85% increase in average throughput without additional power utilization, as compared with fixed data rate operation.

1. Field of the Invention
This invention relates to wireless communication networks and methods and controllers for controlling data rate therein.
2. Background Art
Feedback control of transmit power in wireless networks is a well established technology from both theoretical and practical perspectives. In contrast, control of data rate has been discussed in the following articles, where its efficacy has been demonstrated by simulations: M. B. Pursley and H. B. Russell, "Network Protocols for Frequency-Hop Packet Radios With Decoder Side Information," IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, Vol. 12, No. 4, pp. 612-621, 1194; M. B. Pursley and C. S. Wilkins, "Adaptive Transmission for Frequency-Hop Communications with Reed-Solomon Coding," in PROC. PACIFIC RIM CONFERENCE ON COMMUNICATIONS, COMPUTERS AND SIGNAL PROCESSING, (Victoria, Canada), pp. 866-869, 1997; and J. H. Gass, M. B. Pursley, H. B. Russell, R. J. Saulitis, C. S. Wilkins, and J. S. Wysocarski, "Adaptive Transmission Protocols for Frequency-Hop Radio Networks," in PROC. IEEE MILITARY COMMUNICATIONS CONFERENCE, pp. 282-286, 1998.
A wireless communication network can be viewed as a serial connection of three functional, rather than physical, blocks that represent relations between the system's variables as shown in FIG. 1.
In FIG. 1, E(k) is the energy with which the kth packet is transmitted. Since packet duration is fixed, energy and power can be used interchangeably. Block 1 represents the functional relation between E(k) and the received signal-to-noise ratio (SNR), r(k). This includes the effect of shadowing, h(k), path loss, ρ(k), and channel noise with multi-user interference, N(k). In particular, this relation takes the form
                                          r                                      (              k              )                                =                                                    F                1                                                          (                                                      E                                                              (                      k                      )                                                        ,                                      h                                                              (                      k                      )                                                        ,                                      ρ                                                              (                      k                      )                                                        ,                                      N                                                              (                      k                      )                                                                      )                                      =                                                            h                                                        (                    k                    )                                                                                ρ                                                        (                    k                    )                                                                                E                                                        (                    k                    )                                                                              m                                                                                n                                                                                N                                                        (                    k                    )                                                                                ,                            (        1.1        )            where n is the number of coded symbols per packet and m is the number of bits representing each coded symbol.
Block 2 represents the relation between r(k) and the bit error probability, pbe(k). The perturbation γ(k) that acts on Block 2 is the channel uncertainty. γ(k) represents the parameter that characterizes a Rician fading channel with binary frequency shift keying (BFSK) modulation and noncoherent demodulation:
                                          p            be                                          (            k            )                          =                                            F              2                                                  (                                                r                                                        (                    k                    )                                                  ,                                  γ                                                        (                    k                    )                                                              )                                =                                                    1                +                                                      γ                    2                                                                          (                    k                    )                                                                              2                +                                                                            γ                      2                                                                                (                      k                      )                                                                                (                                          2                      +                                              r                                                                          (                          k                          )                                                                                )                                                                                exp                                                  (                                      -                                                                  r                                                                          (                          k                          )                                                                                2                        +                                                                                γ                              2                                                                                (                              k                              )                                                                                (                                                          2                              +                                                              r                                                                                (                                  k                                  )                                                                                )                                                                                )                                            .                                                          (        1.2        )            When γ(k)=0, the channel is an additive white Gaussian noise (AWGN) channel; when γ(k)=∞, it is a Rayleigh fading channel.
In the decomposition of the physical wireless channel into Blocks 1 and 2, the first block models the total average received energy and the second the split of this energy between the direct path and multipath. A rigorous justification of this decomposition can be obtained following the arguments given in the prior art.
Block 3 represents the relation between pbe(k) and the probability that the kth packet is successfully transmitted, pst(k), assuming that q(k) data symbols were included in the packet of length n, i.e., n−q(k) symbols were devoted to coding. In this application, it is assumed that a Reed-Solomon (RS) code is used, in which case this relation is given by:
                                          p            st                                          (            k            )                          =                                            F              3                                                  (                                                q                                                        (                    k                    )                                                  ,                                                      p                    be                                                                          (                    k                    )                                                              )                                =                                    ∑                              j                =                0                                            ⌊                                                      n                    -                                          q                                                                    (                        k                        )                                                                              2                                ⌋                                                                                (                                                                            n                                                                                j                                                                      )                                                                            (                                      1                    -                                                                  (                                                  1                          -                                                                                p                              be                                                                                (                              k                              )                                                                                )                                            m                                                        )                                j                                                                                (                                          1                      -                                                                        p                          be                                                                                (                          k                          )                                                                                )                                                        m                    -                                          (                                              n                        -                        j                                            )                                                                      .                                                                        (        1.3        )
As the performance measure of this network, its average throughput is defined as:
                                          T            av                    =                                    lim                              K                ->                ∞                                                                                1                K                                                                            ∑                                      k                    =                    1                                    K                                                                  E                                                        [                                          T                                                                    (                        k                        )                                                              ]                                                                                ,                            (        1.4        )            where T(k) is the instantaneous throughput defined asT(k)=q(k)pst(k),  (1.5)and E[·] denotes the expectation.
When the system operates with a fixed transmit power E(k)≡Ed and fixed data rate q(k)≡qd, it is referred to as an open-loop network.
As mentioned above, modern wireless networks use feedback power control to combat disturbances and improve Tav. A functional block diagram of a system with feedback power control is shown in FIG. 2. In this Figure, rd represents the desired level of SNR, and the deviation of r(k) from rd is the argument of the control law F4. In practice, this law may be selected as:EdB(k+1)=EdB(k)+Δsign(rd−r(k)),where EdB(k)=10 log10E(k), Δ>0 is a step in power increase/decrease, and
      sign              (      x      )        =      {                                        1            ,                                                                              if                                                                                x                            >              0                        ,                                                            0            ,                                                                              if                                                                                x                            =              0                        ,                                                                          -              1                        ,                                                              if                                                                                x                        <            0.
If this controller operates efficiently, r(k) at the output of Block 1 is close to rd and Tav, defined by (1.4), is improved compared to open-loop performance. However, even if the disturbances h(k), ρ(k), and N(k) are compensated for completely, i.e., r(k)≡rd, the channel uncertainty, γ(k), being outside of the control loop, would not be rejected, which would adversely affect Tav. Therefore, further control measures, intended to accommodate γ(k) and, in addition, help feedback power control in combating h(k), ρ(k), and N(k) are desirable.
Another input variable that may be controlled is the data rate, q(k). However, feedback control of q(k) does not seem to be feasible. Indeed, whereas in power control one can defined the desired SNR (i.e., rd), in rate control no desired set point for q(k) can be defined since it would depend on the unknown factors, for instance, h(k) and γ(k). Therefore, feedback control of q(k) is not feasible.
It should be pointed out that in asynchronous transfer mode (ATM) networks, feedback control of data rate is not only possible but is quite efficient. The reason is that in the ATM environment the occupancy of buffers at the switching nodes is affected by the admission data rate and therefore, regulating buffer occupancy to the desired level, effectively regulates data rate in a feedback manner.
Another possibility to consider would be feedforward control. To accomplish this, one would need to use the probability of bit error, pbe(k), and calculate q(k) so that the instantaneous throughput T(k), defined by (1.5), is maximized. A block diagram of the network with both feedback power control and feedforward rate control is shown in FIG. 3.
There are, however, impediments to this approach. First, pbe(k) is not known in real-time, and what might be available is the number of bit errors, nbe(k), when the packet is successfully decoded by a block code. Second, even if pbe(k) were known, it would be available only after the transmission took place, i.e., pbe(k) would have to be used to calculate not q(k) but q(k+1). Consequently, there is a need for a practical feedforward controller that overcomes these impediments.

Method and controller for data rate adaptation in wireless communication networks

The Regents of the University of Michigan


This disclosure pertains to a unique, versatile article for providing both storage and display of clothing, headwear, and other items within the internal area of an automated vehicle. Such an article is symmetrical in shape with a three-dimensional configuration having two opposing ends with curved edges and a bottom portion extending outward and below a top ovate portion with four corner regions having leg components that incline upward. Such an article allows for placement of headwear, clothing, and other types of items over the ovate top portion with the inclined legs of the bottom extended portion present for retention thereof. Clips may be attached for facilitating such retention as well, particularly on the bottom portion legs. Such an article may be placed anywhere on and attached to internal vehicle portions, including a dashboard, windows, seat backs, and the like, utilizing adhesives, suction cups, and other means.

The capability of storing and simultaneously, if desired, displaying clothing, headwear, and other like articles within the internal portions of a vehicle have been quite limited over the years. Typical vehicles will include certain hooks in the rear portion thereof for the purpose of either directly hanging an article of clothing or permitting a hanging device to attach thereover for placement of the subject clothing (or headwear, etc.) as needed. Such hooks may either be provided outwardly within the vehicle extending from an internal door frame or wall, or provided as an extending (and returning) movable hook in the same basic area, albeit allowing for a recessed device that may be utilized on demand. Although such alternatives do provide a semblance of utility for such a purpose of clothing placement and storage during transport, such locations of hooks require the user to drape the subject clothing, etc., downward over the rear door window, potentially causing difficulties as to visibility. The static location of such built-in hanging devices leaves the user at the mercy of the resultant disposition of such hanging clothing articles, etc. The user may wish to place, for instance, wet articles at a location that does not cause visibility issues and potentially over a container or other article to catch dripping water and moisture. Thus, for example, the potential for hanging such wet clothes (and the like) at a rear window that is not located over an upholstered seat, but, instead, a flat floor that may be covered with an impermeable (tarp, for instance) while retained at a height for such a purpose, and additionally in a manner that allows for a broader extension of the wet clothing (rather than over a hook, for instance), is simply not accorded users as of today.
Additionally, such hooks are not the most reliable as to retaining subject clothing, etc., as the size and configuration of such hooks are such that anything of a too-large size or cumbersome shape may easily become detached (or at least fall) from the hooks themselves. Certainly, if the user has sought usage of such a hook for keeping a clothing article in a certain shape, or for that matter, a wet article from falling down to aid in drying out, the hooks provided for such purposes lack reliability for the most part.
Furthermore, a user may seek to not only store or hang clothing, etc., but also a means of displaying outwardly certain logos, messages, etc., therefrom. For example, certain headwear, particularly baseball caps, as a non-limiting example, are known to include over-the-bill representations (team names, logos, outward messages, and the like) that a user may wear for the purpose of supporting a team, delivering unspoken positions, etc. While worn such is easily accomplished, certainly. However, the user may wish to display such a logo, message, etc., when not worn and, in this situation, while driving or riding in a vehicle. Such a display potential is limited to, for instance, simply placing a cap on a dashboard for outward display through a windshield. This may be problematic, however, ostensibly because of the lack of securing such a headwear article to the dashboard, thus potentially having such a cap move and/or fly up in such a manner as to compromise the driver's visibility. A user may further wish to store a collection of caps on a dashboard within a vehicle, particularly with one outward facing and the others nested behind in a uniform fashion. The simple alignment of caps together without any base leaves the potential for detachment and movement of all, such as, for example, with a quick brake stoppage, a swerve to avoid an obstacle, or even a wind gust with an open window. As such, to provide a safer alternative in this manner, there should be provided an article that allows for increased capability for the user's benefit. Nothing is provided in this way within the pertinent art.
As it is, then, the ability to permit a user the capability of utilizing an on-demand article for clothing, headwear, etc., display/storage within the internal region of an automated vehicle (car, van, minivan, truck, semi, etc.), particularly for any such purpose with a versatile device for any such desired use, is simply not present within the pertinent industry. In other words, the provision of an article that may be utilized for display of a cap outwardly on a dashboard, may hold multiple caps simultaneously in such a manner, may be utilized as a window-attached clothing hanging article, or even on the back of a seat (clipped or otherwise attached with clothing, etc., hanging therefrom), has not been disclosed or utilized as of today. The versatility and utility of such an article would be a great benefit for vehicle users of any type; unfortunately, again, to date, such an article has yet to be explored within the pertinent vehicle storage/display industry to date.

Hat and clothing storage and display article


A foldable quad-chord truss which can be connected end-to-end with like trusses. The chords of each pair of chords are rigidly attached, and connector members intermediate the ends are each swivelly attached to each of the chords of each chord pair to effect the folding into a compact shape for transport and storage. The connector members are adapted for attachment to beams or connector members thereof which beams may extend between a parallel pair of the trusses.

Prior art platforms include those disclosed in Applicant's U.S. Pat. Nos. 5,730,248; 5,921,346; 6,003,634; 6,135,240; 6,138,793; 6,227,331; 6,264,002; 6,302,237; 6,386,319; and 6,523,644.
A modular trussed platform is described in Australian patent 774316 which utilizes cluster posts between which truss units are attached, which allows the trusses to span in both longitudinal and transverse directions.
U.S. Pat. Nos. 7,779,599 and 7,941,986 disclose a work platform wherein a plurality of joists, such as trusses, are pivotally attached to a plurality of hubs.
U.S. Pat. No. 8,123,001 discloses a modular platform/scaffolding which does not utilize underlying cables but instead relies on the use of, for example, cables attaching the platform to an upper structure or supports from below for supporting the platform.
A quad-chord truss is one which has four elongate members or chords which extend longitudinally of the truss, with bracing or the like connecting the chords to form a rigid unitary framework, i.e., the truss. Examples of quad-chord trusses are found in U.S. Pat. Nos. 5,711,131, 6,026,626, and 7,028,442.
All patents and published patent applications disclosed herein are incorporated herein by reference.


A method and apparatus process content written in an application form. In one embodiment, stroke data corresponding to content written in fields of an application form is obtained from an e-pen. Then, words corresponding to the written content are extracted from the stroke data and confidence value is assigned to each of the words with respect to each of fields in the template application form. Each of the words corresponding to the written content is mapped to one of the fields in the template application form based on the confidence value assigned to each of the words. Moreover, a tag is assigned to each of the words indicating a mapping between each of the words and one of the fields, and the words along with the assigned tags are stored in the storage unit.

E-Pen provides written content on an application form in form of strokes. The strokes position obtained from the e-pen may have non linear distortions. For example, the strokes have in-accuracies which vary very widely along the width and height of the application form. For example, the tilt in the e-pen while writing on the application form may result in in-accuracies in the data. If you map the co-ordinates the stroke data directly to the application form, lot of errors may occur due to the tilt in the e-pen and in-accuracies of the stroke data.
Typically, content written using an e-pen on an application form is recognized first and then stored in database in corresponding fields of the application form. Many engines are currently known for recognizing written strokes of the e-pen. However, none of the existing recognition engines provide the corresponding position of the pen content to remove inaccuracies in e-pen data.
Consider an empty application form with exact spatial locations of fields as shown in FIG. 1A. As shown, the application form includes name field, date field and age field along with their respective spatial location. For example, the name field starts at 3″ and ends at 4″ in Y direction and starts at 2″ and ends at 10″ in X direction.
Consider that, a user writes content in fields of the application form using an e-pen as shown in FIG. 1B. When the content is filled in each field, the written content like 18 in the age field along with the start location (X, Y) and end location of word (X,Y) is recorded in the e-pen. The stored content or pen strokes along with respective spatial locations are then mapped with corresponding fields of a template application form. For example, upon mapping, the recognition engine may recognize that the pen strokes 18 belong to the age field and 25-02-2010 belong to the date field. This may be the case when the e-pen data does not have inaccuracies. In majority of the cases, the e-pen may provide in-accurate data due to the tilt of the e-pen as well as inherent errors in the e-pen, resulting in mapping of the pen strokes to the wrong fields of the template application form.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

Method and apparatus for processing content written in an application form using an e-pen


An indicator is disclosed that detects the presence of a chemical residue. The indicator includes a substrate having an upper surface and a lower surface and a first portion and a second portion joined at a fold line. The first portion is smaller in area than the second portion. An adhesive coats the upper surface of at least the second portion of the substrate. A first reactant is adhered to the upper surface of the first portion of the substrate. When the second portion is contacted with a surface containing the chemical residue, the residue adheres to the adhesive and when the first portion is subsequently folded along the fold line so that the upper surfaces of the substrate contact each other, a portion of the adhesive on the second portion remains exposed and the first reactant and chemical residue react to provide the color indicia indicating the presence of the chemical residue.

It is a common practice for security personnel to inspect and test packages, purses, etc. for dangerous, illegal or hazardous items prior to persons entering secure areas, e.g., airports, public events, etc. It is also common for security personnel to inspect and test vehicles (automobiles) for hazardous materials.
This invention relates to simple, disposable stickers used by security personnel guarding a secure area, facility, or transportation vehicle to indicate that a person, package, or vehicle entering such secure areas has been inspected and is permitted to be therein.
Also, these simple, disposable stickers may be fabricated so as to perform trace analysis on the inspected article.
More specifically, this invention relates to a self-expiring inspection sticker that provides a positive, visible indication that the article or vehicle to which it is affixed has been inspected for weapons, contraband, etc.
This invention also relates to this type of adhesive sticker construction being used as a testing device, to test for explosives, narcotics, and other contraband items. These adhesive stickers may even be used to seal the article for a short period of time after inspection.


Practice of this invention provides, at least, a method of making a hydrogen storage material comprising the steps of:

The present invention relates to electrochemical hydrogen storage alloys, rechargeable electrochemical cells, fuel cells using these alloys, and to methods of manufacturing the same.
More particularly, the invention relates to rechargeable cells, batteries, and fuel cells having at least one electrode formed of multicomponent, electrochemical hydrogen storage material or alloy. In one embodiment, such multicomponent alloys include discrete regions, small in size and widely distributed as will be hereinafter described, which differ compositionally from the bulk alloy and which contribute to the high rate capabilities of the alloys of the present invention. The present invention also includes methods of manufacturing the improved alloys to significantly further enhance such improved performance characteristics. The methods of the present invention assure that the size range and distribution of the aforementioned regions are optimized for enhancement of the rate capabilities of the alloys of the invention. Cells that incorporate these alloys have significantly improved performance characteristics, particularly with respect to exhibiting high discharge rates.
Rechargeable cells that use a nickel hydroxide positive electrode and a metal hydride forming hydrogen storage negative electrode (xe2x80x9cmetal hydride cellsxe2x80x9d) are known in the art.
When an electrical potential is applied between the electrolyte and a metal hydride electrode in a metal hydride electrochemical cell, the negative electrode material (M) is charged by the electrochemical absorption of hydrogen and the electrochemical evolution of a hydroxyl ion; upon discharge, the stored hydrogen is released to form a water molecule and evolve an electron:   M  -  H  +            e      -                          ⟷        charge            discharge            M    -  H  +      OH    -
The reactions that take place at the positive electrode of a nickel metal hydride cell are also reversible. Most metal hydride cells use a nickel hydroxide positive electrode. The following charge and discharge reactions take place at a nickel hydroxide positive electrode:             Ni                    (        OH        )              2    -            OH      -                          ⟷        charge            discharge            NiOOH    +            H      2            O    +      e    -
In a metal hydride cell having a nickel hydroxide positive electrode and a hydrogen storage negative electrode, the electrodes are typically separated by a non-woven, felted, nylon or polypropylene separator. The electrolyte is usually an alkaline aqueous electrolyte, for example, 20 to 45 weight percent potassium hydroxide. The first hydrogen storage alloys to be investigated as battery electrode materials were TiNi and LaNi5. Many years were spent studying these simple binary intermetallics because they were known to have the proper hydrogen bond strength for use in electrochemical applications. Despite extensive efforts, however, researchers found these intermetallics to be extremely unstable and of marginal electrochemical value due to a variety of deleterious effects such as slow discharge, oxidation, corrosion, poor kinetics, and poor catalysis. These simple alloys for battery applications reflect the traditional bias of battery developers toward the use of single element couples of crystalline materials such as NiCd, NaS, LiMS, ZnBr, NiFe, NiZn, and Pb-acid. In order to improve the electrochemical properties of the binary intermetallics while maintaining the hydrogen storage efficiency, early workers began modifying TiNi and LaNi5 systems.
The modification of TiNi and LaNi5 was initiated by Stanford R. Ovshinsky at Energy Conversion Devices (ECD) of Troy, Mich. Ovshinsky and his team at ECD showed that reliance on simple, relatively pure compounds was a major shortcoming of the prior art. Prior work had determined that catalytic action depends on surface reactions at sites of irregularities in the crystal structure. Relatively pure compounds were found to have a relatively low density of hydrogen storage sites, and the type of sites available occurred accidently and were not designed into the bulk of the material. Thus, the efficiency of the storage of hydrogen and the subsequent release of hydrogen was determined to be substantially less than that which would be possible if a greater number and variety of active sites were available.
Ovshinsky had previously found that the number of surface sites could be increased significantly by making an amorphous film that resembled the surface of the desired relatively pure materials. One of the characteristics of hydrogen storage alloys, particularly electrochemically activated hydrogen storage alloys, which researchers have sought to improve is the hydriding-dehydriding kinetics, or the speed of hydrogen absorption and desorption. This affects the charge and discharge rates at which the battery can operate and determines the applications for which the battery is suitable. For example, such applications as hybrid electric vehicle propulsion require very high discharge rate capabilities in order to meet vehicle torque and acceleration requirements and also very high charge rates to accommodate regenerative braking requirements.
An approach to improving these kinetic characteristics has been to explore mixing alloys of the TiNi and LaNi5 types. TiNi alloys are often referred to as AB2 alloys and LaNi5 alloys as AB5 alloys.
Bououdina, et al. describe, in xe2x80x9cImproved Kinetics by the Multiphase Alloys Prepared from Laves Phases and LaNi5xe2x80x9d as published in Journal of Alloys and Compounds 288 (1999) 22-237, a new method to prepare hydrogen absorbing alloys from single phase intermetallic ones. To improve speed of hydrogen absorption and desorbtion, these authors intended to improve the hydriding-dehydriding kinetics, or speed, of the single phase system found in chromium and nickel modified Zirconium/Titanium Laves alloy (an AB2 type alloy). This was accomplished by melting of two single-phase intermetallic compounds. Of particular interest was addition of LaNi5 (an AB5 type alloy) to the described Laves AB2 alloy. This combination was chosen in light of the difficulties of preparing homogeneous alloys using rare earth elements and a Laves phase alloy, which stem from the approximately 750xc2x0 C. difference in melting temperatures. Another consideration was the ease of preparation of the LaNi5 as a single-phase material and its higher hydrogen kinetics coupled with a flat plateau for charging and discharging.
Yang et al. describe, in xe2x80x9cContribution of Rare-Earths to Activation Property of Zr-based Hydride Electrodesxe2x80x9d as published in the Journal of Alloys and Compounds, 293-295 (1999) pgs. 632-636, the effect of alloying cerium and either cerium-rich mischmetal or lanthanum-rich mischmetal on the crystalline characteristics and electrochemical performances of AB2 type hydride electrodes. Alloys of compositions ZrMn0.5Cr0.10V0.3Ni1.1 and Zr0.9T0.1Mn0.5Cr0.10V0.3Ni1.1 (T=Ml, mischmetal, or cerium and Ml=lanthanum-rich mischmetal) were prepared by arc melting under argon atmosphere with as-cast alloy ingots being crushed mechanically in air. Hydride electrodes were prepared by cold pressing the mixtures of different alloy powder with powdered copper in a weight ratio of 1:2 to form porous pellets of 10 mm diameter. Electrochemical charge-discharge tests were carried out in a trielectrode electrolysis cell in which the counter-electrode was nickel oxyhydroxide with excess capacity, the reference electrode was Hg/HgO.6M KOH, and the electrolyte was 6 M KOH solution. Discharge capacities were determined by galvanostatic method.
It was determined that cerium or mischmetal alloying can xe2x80x9cbasicallyxe2x80x9d solve the problem of activation of a ZrMn0.5Cr0.10V0.3Ni1.1 alloy electrode and that after rare-earth alloying, the maximum capacities rise from 250 mAh/g of the mother alloy ZrMn0.5Cr0.10V0.3Ni1.1 to 356 mAh/g of the cerium-containing one.
Yang et al. describe, in xe2x80x9cActivation of AB2 Type Zr-based Hydride Electrodesxe2x80x9d as published in ACTA METALLURGICA SINICA, Vol 11, No. 2 (April 1998) pgs. 107-110, the effect of lanthanum alloying on the crystalline characteristics, electrochemical capacity, and activity of AB2 type Zrxe2x80x94Crxe2x80x94Ni hydride electrodes. The alloys studied were prepared by arc melting under argon with the purity of the constituent metals above 99.9%. The as-cast alloy was crushed mechanically in air and sieved through 360 mesh. Hydride electrodes were prepared by cold pressing, with 300 mesh powdered electrolytic copper in a 1:2 weight ratio, to form porous 10 mm diameter pellets in copper holders. Electrochemical charge-discharge tests were carried out in a trielectrode electrolysis cell in which the counter-electrode was nickel oxyhydroxide with excess capacity, the reference electrode was Hg/HgO.6M KOH, and the electrolyte was 6 M KOH solution. Discharge capacities were determined by galvanostatic method.
The previously mentioned researchers found some level of incremental improvement in the hydriding/dehydriding kinetics of this combination of AB2 and AB5 metals. For the instant invention, however, we have found that development of short-range order, on the sub-micrometer to few micrometer level, will yield discreet regions of TiNi5-type alloys in a matrix of the TiNi-type alloy. While not wishing to be bound by theory, it is possible that there is some catalytic activity occurring at the surface of the TiNi5-type discreet region; it is possible that a synergistic effect relating to hydrogen catalysis or storage occurs at the TiNi-type matrix material boundary or interface with the TiNi5 region. Whatever is occurring, it is of notable beneficial use for electrochemical hydrogen catalysis, storage, reaction surfaces, and their combinations. While the mechanism of function here may not be understood clearly at the moment, we do know that with this combination of phases coupled with a rapid solidification, cooling, or quenching we obtain excellent electrochemical hydrogen storage with excellent electrochemical hydriding/dehydriding activity or, simply, excellent hydrogen kinetics and storage.
U.S. Pat. No. 5,554,456, issued to Ovshinsky, et al. Sept. 10, 1996, describes non-uniform heterogeneous powder particles for electrochemical uses, and said powder particles comprising at least two separate and distinct hydrogen storage alloys blended together. This invention notes the usefulness of magnesium-based alloys among others and describes methods of inclusion of multiple alloys in electrochemically activated hydrogen storage materials.
Appreciation of the Ovshinsky principles of disorder or ovonics requires that order and disorder be recognized at different levels particularly including those of composition, structure, and translation. Respectively, these levels of order or disorder may be considered on a distance scale of a few through several interatomic distances, through hundreds of interatomic distances, to generally more than a thousand interatomic distances. Again respectively, these varying scales of disorder will affect a material""s crystal structure or lack thereof, a material""s inter-grain boundaries or lack thereof, as well as a material""s morphology and surface characteristics. Application of these principles is useful in the field of energy storage but all levels of possible disorder must at least be recognized and dealt with to provide optimum overall properties. Some have dealt with different portions of the spectrum of ovonic principles, those of disorder, to advance the art. This invention recognizes the work of others and advances or builds upon those contributions to more fully realize the benefits of disordered ovonic materials by combining properties in a useful manner, and recognizing at least the translational level of disorder to gain benefit from such properties.
Ovshinsky describes, in xe2x80x9cAmorphous and Disordered Materialsxe2x80x94the Basis of new Industriesxe2x80x9d as published by The Materials Research Society in Materials Research Society Symposium Proceedings, vol. 554 (1999), pgs. 399-412, the principles of disorder and provides useful conceptual means for their understanding. Others have noted the usefulness of hydrogen absorptive materials and have worked with alloys of interest. Still others have recognized the usefulness of high hydrogen kinetics or rapid absorption/desorption of hydrogen, and worked with such materials. Beyond these researchers, others have combined two materials with differing characteristics. None, however, have arrived at the methods or means for producing the high capacities for rapid charging and high rate dependable discharging as well as stable storage capacity and high surface area as combined in the materials attainable through practice of our invention.
This invention provides, at least, electrochemical hydrogen storage materials with excellent storage capacity and excellent hydrogen kinetics. Such materials are very well suited to serve as electrodes for batteries, fuel cells, and in other applications in which high surface activity may be useful. Such products are obtained by combining alloys having good electrochemical hydriding/dehydriding characteristics with alloys having good electrochemical hydrogen storage capacity. These respective materials are the LaNi5-type materials or alloys and the TiNi-type alloys or materials; as noted earlier, these are also known in the art as, again respectively, AB5 and AB2 alloys or materials.
In particular, our invention provides multi-phase hydrogen storage materials suitable for use as electrode material for electrochemical reactions, energy generation, energy storage, combinations of these, and as reaction surfaces. This is accomplished by providing a combination of alloy phases in a unique microstructural arrangement in which at least one alloy having high hydrogen kinetics or storage characteristics is substantially evenly dispersed in minute, yet distinct, regions within a matrix of at least one alloy having good qualities in the complementary characteristic. This is accomplished by combining the at least two alloys, or their components, melting them and quenching rapidly to form the unique microstructure described. The rapid quenching should be accomplished in a manner to cause minute, discreet regions of one phase to form, yet also in a manner to prevent such minute regions from aggregating or growing too large.
This means that the quenching should be slow enough to allow precipitation to begin and some growth to occur; but rapid enough to prevent growth of overly large regions. Such a scheme may be determined without undue experimentation, particularly in light of the understanding that the benefit in this unique combination and microstructure apparently derives from a surface effect relating to the interaction of the distinct phases; benefit will accrue through optimization of that effect.
As a general matter small particles, or overall enhanced surface area, provide useful reaction surfaces. Smaller particles of this multi-phase alloy system will, in the absence of other competing factors, provide better electrodes or reaction surfaces. A method of enhancing the characteristics of interest for the storage alloys of this invention is gas-atomization. This method allows simultaneous provision of finely divided bulk multi-phase alloy as well as providing a means of attaining the rapid-quenching which is so useful in assuring, for example, the fine dispersion of the highly kinetic alloy phase within the high storage capacity alloy matrix phase in each discreet, atomized and solidified particle of the bulk combination.
Additional benefit appears to accrue by treating the quenched, particularly the atomized, powder in a manner to enhance exposure of the discreet regions of the finely dispersed phase. This may be accomplished by crushing, etching, cracking, and fracturing the particles or otherwise opening pathways for electrolyte media, in the exemplified alloy system, to reach the highly active surfaces or interfacial areas available throughout the individual particles of the alloy system.

Electrochemical hydrogen storage alloys for nickel metal hydride batteries, fuel cells and methods of manufacturing same

Abstract: 1. forming a molten mixture comprising nickel and at least one other transition metal element, the combination of which will form a TiNi alloy and including in said molten mixture from about 0.1 at. % to about 10 at. % of one or more elements which will form an alloy which is immiscible in the TiNi-type alloy; and

Abstract: (b) cooling said molten mixture to form a solid alloy-system material by rapid solidification of said molten mixture at a cooling rate of at least 103xc2x0 C. per second.


According to an aspect of the present invention, there is provided an electronic apparatus including: a housing; a circuit board that is housed in the housing; a connector that is mounted on the circuit board and has a jack opening disposed to be exposed from the housing; and an LED unit that is detachably installed on the connector.

1. Field
An aspect of the present invention relates to an electronic apparatus including a connector provided with an LED.
2. Description of the Related Art
As a modular jack connector of a notebook PC for connecting an LAN cable, the connector with a built-in LED for visualizing an LAN connecting situation has widely spread.
In general, a heat resistant temperature of an LED portion of the modular jack connector is lower than that in other portions. For this reason, for example, the LED provided in the modular jack connector may not be turned on when the modular jack connector is subjected to reflow mounting. In order to prevent the failure, it is necessary to perform the reflow mounting and to then solder the modular jack connector to a substrate individually. In the case in which the LED cannot be turned on, moreover, it is necessary to remove the whole modular jack connector from the substrate and to solder a new modular jack connector. This causes a great deal of time and labor for a repair.
JP-2000-30811-A discloses a connector assembly in which an LED housing is provided and attached to a circuit board separately from the modular jack housing. There is employed a structure in which an LED module is attached to the modular jack housing and the LED module has LED housings for mounting respective LEDs.
In the system, however, a leg of a conductor of the LED housing is attached to a printed circuit board. For this reason, there is a problem in that the LED housing can be attached and removed in only a manufacture of a connector and the LED housing can be neither attached nor removed after a connector is mounted on the printed circuit board. Therefore, it is impossible to replace only the LED when the LED cannot be turned on and it is necessary to remove the whole connector from the substrate in order to perform a repair.


A photoelectric conversion element having a composite dye and an n-type semiconductor, the composite dye having a plurality of component dyes which have different excitation levels and which are chemically bonded to each other to form a straight chain or branched structure for transferring an electron therethrough, wherein the straight chain or branched structure is, at one end thereof, secured to the n-type semiconductor and has, at least at one other end thereof, a free end, wherein, in the straight chain or branched structure, the plurality of component dyes are arranged in an order such that the excitation levels of the plurality of component dyes are decreased as viewed from the one end of the structure toward the at least one other end of the structure.

1. Field of the Invention
The present invention relates to a photoelectric conversion element. More particularly, the present invention is concerned with a photoelectric conversion element comprising a composite dye and an n-type semiconductor, the composite dye comprising a plurality of component dyes which have different excitation levels and which are chemically bonded to each other to form a straight chain or branched structure for transferring an electron therethrough, wherein the straight chain or branched structure is, at one end thereof, secured to the n-type semiconductor and has, at least at one other end thereof, a free end, and wherein the plurality of component dyes are arranged in an order such that the excitation levels of the plurality of component dyes are decreased as viewed from the one end of the structure toward the at least one other end of the structure. The photoelectric conversion element of the present invention exhibits excellent photoelectric conversion properties, especially high efficiency in converting solar energy to electric energy (i.e., high energy conversion efficiency), and a dye-sensitized solar battery can be easily produced therefrom. Therefore, the photoelectric conversion element of the present invention can be advantageously used for a dye-sensitized solar battery and the like.
The present invention is also concerned with a dye-sensitized solar battery using the photoelectric conversion element.
2. Prior Art
Consumption of energy is indispensable to civilized society. Most of the energy which is consumed by civilized society is derived from fossil fuels, in which sunray energy has been accumulated over many years. In recent years, the problem that the amount of fossil fuels available is being reduced and the problem that the burning of fossil fuels causes global warming have arisen, and there is an increasing fear that these problems will be obstacles to the sustainable development of human society.
For solving the above-mentioned problems, various studies have been made to directly utilize sunray energy. Among these studies, the studies on solar batteries have been vigorously made, because solar batteries exhibit high efficiency in converting solar energy to electric energy (i.e., high energy conversion efficiency). Among the solar batteries, special attention has been paid to a dye-sensitized solar battery, which uses a photosensitizer, such as a dye, and which is capable of efficiently taking out electrons from the photosensitizer by the irradiation of the photosensitizer with sunray. Specifically, since Michael Gratzel et al. reported a system which uses a dye-sensitized solar battery having an energy conversion efficiency of more than 7% (see Nature 1991, 353, 737), a dye-sensitized solar battery has drawn special attention as the next-generation solar battery which can be produced at a low cost without use of a complicated method.
In general, a dye-sensitized solar battery has the following structure. A substrate (electroconductive support) is laminated on a support made of glass, a polymer or the like, wherein the substrate has coated thereon an indium oxide membrane (e.g., an ITO (indium tin oxide) membrane) or fluorine-doped tin oxide (FTO) membrane having excellent conductivity and excellent transparency. On the substrate is laminated a porous titanium oxide membrane, as an n-type semiconductor, which is a cheap material and has a size of several tens of nanometers, thereby forming a laminate as a photo-anode. A thin layer of platinum is laminated on a substrate which is substantially the same as the above-mentioned substrate, thereby forming a laminate as a cathode. Between the photo-anode and the cathode is interposed an electrolytic solution containing a redox couple, such as iodine, thereby forming a structure in which a photo-anode and a cathode face each other through an electrolytic solution. In this structure, the photo-anode has carried thereon a dye (such as a complex dye) as a photosensitizer for the purpose of absorbing visible light from sunray to thereby generate excited electrons from the photosensitizer, so that the photo-anode functions as a photoelectric conversion element.
The excited electrons generated from the photosensitizer are transferred to the n-type semiconductor, and further transferred to the cathode through a conductor which connects the photo-anode and cathode. The excited electrons having been transferred to the cathode reduce the electrolytic solution and, in turn, the electrolytic solution reduces the photosensitizer having been oxidized by the emission of electrons from the photosensitizer. By repeating the above-mentioned series of operations, the dye-sensitized solar battery works.
A photosensitizer, such as a dye, can absorb light having wavelengths within a certain range. When the photosensitizer is irradiated with such light having wavelengths within the range, the photosensitizer receives the energy of photons. As a result, electrons in the ground state, contained in the photosensitizer, are excited and transferred to excited states. In general, excited electrons emit energy in the form of heat or light, such as fluorescence or phosphorescence, and return to the ground state. However, when electrons in the photosensitizer are excited, conversion of light energy to electric energy (i.e., photoelectric conversion) is done by taking out the excited electrons from the photosensitizer.
As seen from the above, a photosensitizer plays an important part in the conversion of light energy to electric energy. Therefore, studies on photosensitizers have been vigorously made.
When the function of a photosensitizer is discussed in terms of molecules, the photosensitizer generally receives one photon to excite one electron contained therein. The longer the wavelength of a light, the smaller the energy of the light. It follows from this that a photosensitizer which absorbs a long-wavelength light to excite electrons contained therein (i.e., make electrons contained therein transferred to excited states) can excite electrons contained therein by absorbing a low energy light. Therefore, the photosensitizer can absorb a wide range of light, which ranges from a long-wavelength light to a short-wavelength light, which has a large energy. In the application of a solar battery, for taking out a number of electrons (i.e., obtaining a high electric current), it is important to effectively utilize a wide range of light contained in sunray, which has a wide distribution of light wavelengths. In view of this, various attempts have been made to develop a photosensitizer capable of absorbing longer wavelength light from sunray.
For this purpose, i.e., for obtaining a photosensitizer capable of absorbing longer wavelength light from sunray, it is generally attempted to enlarge a conjugate structure. For example, Japanese Patent Application Prior-to-Examination Publication (Tokuhyo) No. 2002-512729 (corresponding to WO98/50393 and U.S. Pat. No. 6,245,988) discloses a technique in which a single nuclear complex dye having a tridentate ligand is used. On the other hand, Inorg. Chem. 2002, 41, 367 discloses a technique in which a single nuclear complex dye having a quadridentate ligand is used. Further, J. Phys. Chem. B 2003, 107, 597 discloses a technique in which an organic dye having a conjugate structure is used.
Moreover, for obtaining a photosensitizer capable of absorbing longer wavelength light from sunray, a technique using a multinuclear complex having a plurality of metals is disclosed in Unexamined Japanese Patent Application Laid-Open Specification No. 2000-323191 (corresponding to EP1052661). Also, for using a plurality of dyes in combination, a technique in which a plurality of dye layers are laminated is disclosed in Unexamined Japanese Patent Application Laid-Open Specification No. 2000-195569, and a technique in which a plurality of dyes are associated with each other is disclosed in Unexamined Japanese Patent Application Laid-Open Specification No. 2002-343455.
However, the above-mentioned techniques, i.e., the techniques in which a single dye is used for absorbing longer wavelength light from sunray, and the techniques in which a plurality of dyes are used in combination (wherein the dyes receive excited electrons having the same energy level from the electrolyte and transfer the excited electrons to the n-type semiconductor), have a theoretical limit on the energy conversion efficiency when electrons are taken out from sunray having a wide distribution of wavelengths. The reason for this is as follows. As a dye absorbs light having longer wavelengths from sunray, the number of electrons taken out from the dye is increased, so that a larger electric current can be obtained. However, light having a long wavelength has a small energy, so that the energy which can be used for transferring an electron to an excited state is inevitably small. Therefore, a high voltage cannot be obtained.
As mentioned above, in the case of a general photosensitizer, the energy of only one photon is used for exciting a single electron (one-photon absorption). However, in the case of a photosensitizer comprising a specific compound, the energies of two photons can be used for exciting a single electron (two-photon absorption) (see Science 1998, 281, 1653). In such case, it becomes possible to transfer an electron to a high energy level by using only low-energy light having long wavelengths and, hence, the above-mentioned theoretical limit can be overcome. The technique of the two-photon absorption is a technique in which an electron having been excited in a molecule is further excited in the molecule. An electron in an excited state returns to the ground state in a short period of time. Therefore, in the technique of the two-photon absorption, generally, the electron is transferred to a quasi-stable excited state (such as a triplet state) so that the life time of the excited electron (i.e., excitation lifetime) becomes longer, thereby assuring a time sufficient for causing a second excitation of the electron. However, even in the technique of the two-photon absorption, it is necessary for a single molecule to absorb light twice in a short period of time and, hence, the probability that the second excitation of the electron occurs is small, so that it is difficult to take out a number of electrons from the photosensitizer. Therefore, it is difficult to apply the two-photon absorption technique to fields (such as the field of solar batteries) in which it is necessary to take out a number of electrons. Thus, the fields to which it is attempted to apply the two-photon absorption technique are limited to the field of polymerization initiators (see Nature 1999, 398, 51) and the field of photosensors (see Unexamined Japanese Patent Application Laid-Open Specification No. 2001-210857).
In addition, as a technique for efficiently taking out solar energy, J. He et al. propose a technique in which two electrodes facing each other are respectively provided with n-type and p-type semiconductor layers, wherein the semiconductor layers are respectively sensitized by dyes having different excitation levels (see Solar Energy Materials & Solar Cells 2000, 62, 265). However, this technique has a problem in that each of the provision of a semiconductor layer and the adsorption of a dye must be performed a plurality of times, thereby rendering combersome the production of a system used in the technique.


A method for integrating image frames includes receiving for each pixel in at least one image frame a value representative of a sensor measurement. The method includes calculating an average difference of the value representative of the sensor measurement over a subset of the plurality of image frames. The method includes detecting motion in at least one pixel of the image frame in the plurality of image frames based on the calculated average difference of the value representative of the sensor measurement over the subset of the plurality of image frames. The method also includes generating an integrated image frame wherein each pixel having detected motion is integrated by an amount less than that of those pixels for which motion is not detected. The amount of frame integration is based on contrast levels, expected rates of motion, and noise characteristics of sensor input image data.

Generally, the display of images is degraded by motion blur and noise. Prior attempts at image frame integration reduce noise and increase sensor performance. However, the prior attempts at image frame integration are often degraded by motion blur and noise. Thus, a need exists in the art for improved image frame integration.


A receiving portion of a radio communication device includes a circuit periodically moving into a sleep mode of operation. The circuit periodically moves out of the sleep mode of operation in response to a re-activation signal. A first clock signal is generated. Clock pulses in the first clock signal are counted. The re-activation signal is generated each time the number of the counted clock pulses in the first clock signal reaches an updatable number. A second clock signal is generated which has a frequency higher than a frequency of the first clock signal. Clock pulses in the second clock signal are counted during every time interval determined by the first clock signal. An error of the frequency of the first clock signal with respect to the frequency of the second clock signal is calculated on the basis of a result of the counting of clock pulses in the second clock signal. The updatable number is set in response to the calculated error of the frequency of the first clock signal.

1. Field of the Invention
This invention relates to a receiving portion of a radio communication device such as a mobile telephone set.
2. Description of the Related Art
Some mobile telephone sets have receiving portions which periodically fall into a sleep mode of operation. When the receiving portion is in the sleep mode of operation, most of circuits in the receiving portion are deactivated to save electric power. At an expected timing of the transmission of polling signals from a base station, the receiving portion changes from the sleep mode of operation to an awake mode (a normal mode or a stand-by mode) of operation.
UK patent application GB 2297884 A corresponding to Japanese published unexamined patent application 8-251656 discloses a power saving arrangement in a mobile telephone. In UK patent application GB 2297884 A, the mobile telephone has a high frequency system clock, and a processor arranged to process polling signals received while the telephone is in its stand-by condition.
When polling signals are not being received, it is possible for the telephone to be placed in a sleep condition by deactivating the system clock. Re-activation occurs in response to a calibrated number of clock cycles produced by a lower frequency sleep clock. Upon re-activation, system clock counters specifying sub-frame periods and frame periods are re-loaded so that they can be re-activated at the required phase. The phase of these counters is compared with signals received from base stations and modifications are made to system counts as required. The extent to which modifications are required is also used to re-calibrate the sleep clock.
In the power saving arrangement of UK patent application GB 2297884 A, the timing of re-activation is determined by the sleep clock. The re-activation includes re-activation of received-signal processing. Accordingly, a minimum increment or a minimum decrement (a minimum variation unit) of the timing of re-activation of the received-signal processing corresponds to the period of the sleep clock. Thus, it is difficult to vary the timing of re-activation of the received-signal processing by a unit shorter than the period of the sleep clock.
In the power saving arrangement of UK patent application GB 2297884 A, the sleep clock is re-calibrated in response to the result of the comparison between the phase of the system clock counters and the phase of the signals received from the base stations while a frequency error of the sleep clock is not detected.

Receiving portion of radio communication device

Matsushita Electric Industrial Co., Ltd.


A feedthrough device for use in deposition chambers such as chemical vapor deposition chambers and atomic layer deposition chambers and methods using the same in association with such chambers as well as chambers so equipped. The feedthrough device includes an associated heating device to maintain the temperature of the feedthrough device above a predetermined level and thus maintain a temperature differential between the deposition chamber body and a vaporized organometallic precursor as it passes therethrough. The feedthrough device may include a helical groove formed along the surface of a longitudinal body portion thereof to complementarily receive a resistance type cable heater. The heater may further include a temperature sensing device to assist in monitoring and controlling the temperature of the feedthrough device.

1. Field of the Invention
The present invention relates generally to vapor and gas delivery systems and, more particularly, to the heating of a gas line body feedthrough used in a vapor delivery system such as a chemical vapor deposition chamber or an atomic layer deposition chamber.
2. State of the Art
Modern semiconductor processing equipment, specifically chemical vapor deposition (CVD) and atomic layer deposition (ALD) systems, are migrating to the use of organometallic precursors such as tantalum tetraethoxide dimethylamino ethoxide (TAT-DMAE) as well as halogen-metallic chemistries such as TiCl4 and others for metal, metal-oxide and metal-nitride film depositions (collectively referred to herein as organometallic precursors). Conventional precursors have typically been delivered in a gas or vapor state thus making them amenable for use in the vapor deposition process, including ease of maintaining the precursors in the vapor state, as they are delivered to the chamber from the vapor source. However, organometallic precursors are typically delivered for use as a liquid and sometimes as a solid. Many of such precursors have low vapor pressures and others exhibit moderate vapor pressures. The organometallic sources are typically vaporized and transported through the delivery plumbing to the process chamber. Conventional methods of vaporization include the use of bubbler ampoules or direct liquid injection systems, which comprise a chemical ampoule, a liquid flow meter, a heated injector, a carrier gas mass flow controller (MFC) and heated vapor delivery lines between the precursor source and the chamber.
Referring to FIG. 1, a conventional CVD chamber 100 is shown. The chamber 100 includes a body 102 and a lid 104 which are configured to allow removal of the lid 104 from the body 102. The removable lid 104 provides for access to and maintenance of the chamber interior including the chamber cavity 106. A vapor delivery path 107 is conventionally defined to pass through the chamber body 102 using a feedthrough device 108 which connects to the heated vapor plumbing (conduit) 110 at the lower side of the chamber at one end 112 thereof and mates to the lid 104 at the opposite end 114. The vapor delivery path 107 may continue through additional vapor plumbing (conduit) 116 before it travels through the lid 104 and is discharged into the chamber cavity 106 through a vapor delivery head 118, also termed a "showerhead" due to its physical configuration. The vapor is then discharged through the vapor delivery head 118 and is deposited on a semiconductor substrate 120 such as a silicon wafer. The semiconductor substrate 120 is positioned on a susceptor unit 122 during the deposition process as is understood by those of ordinary skill in the art.
One problem with the above described deposition chamber 100 is that the chamber body 102 is maintained at a temperature which is lower than that of the heated vapor plumbing 110. For example, the heated vapor plumbing 110 may be maintained at a temperature of approximately 140 to 160° C. while the chamber body 102 is maintained at a temperature of approximately 45 to 65° C. The reduced temperature of the chamber body 102 causes, through heat transfer, the temperature of feedthrough device 108 to also be lower than that of the heated vapor plumbing 110. The temperature differential between the feedthrough device 108 and the heated vapor plumbing 110 may cause condensation to occur within the vapor delivery path 107 as the vapor passes through the feedthrough 108. Newly utilized organometallic precursors are particularly susceptible to such condensation due to their relatively low vapor pressures.
The occurrence of condensation within the feedthrough 108 may negatively impact the chemical vapor deposition process in various ways. For example, the condensation may result in particulate contaminants flowing through the vapor delivery path 107 and being deposited on the surface of the substrate or wafer 120. Introduction of such particulates ultimately results in a defective semiconductor wafer or other substrate 120 which is unsuited for use in subsequent semiconductor packaging processes.
Additionally, the condensation may cause clogging or material build-up within the feedthrough device 108 as well as in the vapor plumbing 116 positioned downstream therefrom along the vapor delivery path 107. Such clogging may have a deleterious effect on the flow characteristics of the vapor passing therethrough. Additionally, material build-up may have a corrosive effect on the feedthrough device 108 and vapor plumbing 116.
While it is possible to route the heated vapor plumbing 110 around the chamber body 102 such that it connects directly through the lid 104 to the vapor delivery head 118 (thereby eliminating the feedthrough device 108 and additional vapor plumbing 116), in order to provide continual heat to the flowing vapor along the vapor delivery path 107, such a configuration is undesirable for various reasons.
For example, removal of the lid 104 from the chamber body 102 would require mechanical disconnection of the heated vapor plumbing 110. This would increase the amount of time required to service and maintain the CVD chamber 100. Perhaps even more significantly, mechanical disconnection of the heated vapor plumbing 110 would increase the potential for contamination the CVD process and the products produced thereby. Such increased potential for contamination results from the fact that the CVD chamber 100 is conventionally located and operated in a plenum 124 adjacent a clean room (not shown) which may be separated by a barrier 126 from a mechanical room 128. Wafers 120 are passed from the adjacent clean room into the CVD chamber 100 for processing. The implementation of a heated vapor line running exterior to the chamber body 102 in the plenum 124 would require increased maintenance activities within the plenum area 124 resulting in the increased likelihood of particulates and contaminants entering the plenum area 124, or possibly even into the adjacent clean room, each time repair or maintenance is required.
Additionally, the repeated connection and disconnection of the heated gas plumbing (i.e., from the lid 104) leads to the degradation of the mechanical connection. For example, a conventional mechanical connection used in chemical delivery systems includes a VCR® metal gasket face seal fitting. The VCR® fitting provides for the compression of a metal (or sometimes polymer) gasket between two opposing toroid surfaces. After repeated compression (i.e., resulting from repeated disconnection and connection of the piping) the toroid surfaces will flatten out and ultimately fail to seal. This necessitates costly replacement of the fitting and may possibly require the fabrication and welding of new piping hardware.
In view of the shortcomings in the art, it would be advantageous to provide a deposition chamber which allowed for the use of organometallic precursors having relatively low vapor pressures without condensation of such organometallic precursors occurring during delivery of the vapor to the chamber.
It would also be advantageous to provide a method of modifying existing deposition chambers to allow the use of organometallic precursors therewith. Particularly, it would be advantageous to provide a method of converting a chemical vapor deposition chamber configured for use with conventional precursors into an atomic layer deposition chamber or a chemical vapor deposition chamber suited for use with organometallic precursors.

Heated gas line body feedthrough for vapor and gas delivery systems and methods for employing same


The invention is directed to methods and apparatus for transmitting data between a first node and a second node in a communications network, for example a wireless network. The method comprises the steps of selecting a transmission channel from a predetermined set of transmission channels according to probability information and transmitting data using the selected channel. The probability information is based on a determination of a characteristic of previous transmissions using each of said set of channels. The invention is also directed to a method of selecting a channel at a node in a communications network for communication with a second node.

A communications network may comprise a number of nodes which are connected by communication paths or links. There may be many possible channels which can be used to communicate between two nodes over a single communication path. These channels may be defined by parameters, which may include, but are not limited to, frequency (i.e carrier frequency), coding scheme, time slot and beam selection.
Before data can be transmitted across a communication path, it is necessary to decide which channel should be used. Each of the channels is unlikely to provide an equal quality link and this is particularly true in the case of wireless links which will be affected by interference from other radio sources in the vicinity and also from communications across other paths in the network.
Several techniques have been proposed to select a channel in order to be able to transmit data. In some situations the quality of each channel is measured prior to making the selection and the best quality channel is selected. This requires a lot of measurement overhead in order to determine the best channel and may require additional signalling.
In GSM and Bluetooth a technique of frequency hopping is used. Both the nodes which are communicating switch between frequencies according to the same predetermined pattern. This uses all possible channels for a short period of time each and ensures that nodes do not dwell on a poor quality channel.
Alternatively, the network can include an overall control entity which manages allocation of channels for communication paths. However, in some circumstances the use of an overall control entity is problematic. Reasons for this include inflexibility to changes in network structure and environmental conditions etc and also large computational and signalling overheads. Additionally, a system using an overall control entity does not scale well.


The present invention comprises block copolymers of alkylene oxides, such as ethylene oxide and propylene oxide, which are further formulated with additional polymers such as poly(N-vinylpyrrolidinone), poly (vinyl alcohol), and certain low foam additives. These polymers are useful for the coating of alumina powders for use in ceramics. In aqueous media, their lower viscosities enable facile spray drying of the coated alumina powders. The coated alumina powders may be compressed under relatively low pressure into high density forms with superior unfired compressive strengths (green strength), they are surprisingly insensitive to relative humidity, are readily ejected from the mold, and finally do not have a deleterious effect upon the ultimate high temperature sintering of the formed bodies.

The formation of ceramic shapes from ceramic powders normally involves pressing or extrusion of a mixture of the ceramic powders and various additives so that a dense cohesive structure is formed which is then heated in a kiln (fired) to destroy any residual organic components and to promote the sintering of the inorganic powder so that further densification and strengthening results. It is essential to produce a final structure with minimal free voids between ceramic powder particles in order to achieve the highest possible density and tensile strengths of the green and sintered bodies. Although pressure of formation plays an important role in densification, pressing under high loads (>100 MPa) will not convert ceramic powder alone into a firm body. The shape formed in this manner would simply crumble when ejected from the die or mold. Organic binders are used to overcome these problems. Organic binders provide lubricity to facilitate the compression of the green structure into a high density form, and adhesion so that the "green", unfired, body holds together. Upon firing and the onset of sintering, the organic binder is no longer required. Complete pyrolysis of the organic material present, so that there are no residues which might adversely affect the sintering process, occurs in the early stages of the firing process.
In practice, the ceramic powder, e.g., alumina, is dispersed in a liquid carrier (water or organic) with the aid of chemical dispersants and mechanical action. A dispersant is necessary in order to make a stable, liquid dispersion at high solids. Although a variety of materials may be used for this function, frequently a low molecular weight poly(acrylic acid) as its sodium or ammonium salt is used. The level of use of this dispersant is usually in the range of 0.05-0.5% by weight based on alumina. Other dispersants that have been used are poly(methacrylic acid) salts and lignosulfonic acid salts. An organic polymeric binder and other functional materials such as lubricants and sintering aids are then added. The resulting slurry or slip is spray dried to yield a free-flowing powder consisting of spherical agglomerates (granules) of about 50-200 micrometer diameter. Approximately 2-8% binder (based on the dry weight of powder) is commonly used. The formulated powder can next be pressed to the desired shape in a suitable die from which it is then ejected.
The viscosity of the complete slurry must be suitable for necessary handling and spray drying. Although spray dry equipment and running conditions may be adjusted to handle a variety of viscosities, larger particles will result from higher viscosity slurries. The resultant large particles may result in larger interstices between particles and hence a lower strength. The binder may contribute to viscosity of the continuous phase of the slurry by virtue of its molecular weight, solubility, conformation in solution, and possible incompatibility with the combination of powder and dispersant. The spray-dried blend of powder and binder must be free flowing so that it can completely fill dies.
The resulting compacted part must be smoothly ejected, be as dense as possible, and not suffer significant dimensional change from that of the die. Chemical additives have a major effect on the desired lubricity. Polyethylene oxides and fatty acid derivatives promote lubrication (the former may also behave as a binder). During dry pressing, the granules are deformed and the binder flows to fill available space, thus increasing density. The glass transition temperature (Tg) of the polymer can have a strong effect in this step. Polymers with too high a glass transition temperature will not flow and as a result cohesion of the pressed part does not occur. Under these conditions, the compressed powder will undergo stress relaxation in the form of expansion on release from the die. This phenomenon is referred to as "springback" and is undesirable from the standpoint of dimensional accuracy as well as density and strength. For this reason, plasticizers are used with higher Tg polymers. Frequently, mixtures of polymers having greatly different physical properties are used as binders. For example, a plastic material such as polyethylene oxide may be blended with a film-forming binder such as polyvinyl alcohol to give an effective ceramic binder.
The polymer binders currently used for the binding of ceramic powders have, as a class, not been specifically synthesized for optimal densification and green strength of ceramic forms. Rather, they are commercially available materials, with other principal uses, which have been adapted for use in ceramic manufacture and include such materials as cellulose ethers, polysaccharides, polyacrylic latexes, poly(2-ethyl-2-oxazoline), poly(ethylene oxide), poly(vinyl alcohol), poly(vinyl butyral), and wax. Of these, poly(2-ethyl-2-oxazoline), poly(ethylene oxide), poly(vinyl alcohol), and wax are used in the spray drying process.
The principal function of the binder is to hold the compacted form together after pressing. The method utilized for determination of suitable "green strength" is the diametral compression strength or DCS of a cylindrical section across its diameter. DCS is actually a measure of tensile strength. The unit of measurement of the pressure tolerance is the megapascal (MPa). Typical values for DCS of "green" parts are in the range 0.3-3.0 MPa. It should be recognized that the strength of the green part is largely a function of the state of the binder phase. If the binder does not flow (as in the case of too high a Tg), or if it is a liquid (as in the case of too low a Tg), a weak non-coherent green part will result. The binder must coat/wet the ceramic powder, flow easily at the pressure and temperature of the die, and be cohesive at the test temperature.
Binders must be cost effective and highly soluble in water or suitable organic solvents, such as alcohols, toluene, or xylene.
Oxide ceramics absorb atmospheric moisture. Since water is known to plasticize alumina and many hydrophilic organics, alumina green bodies will lose strength when exposed to humid conditions (R. A. Dihilia et al, Advan. Ceram. 9, 38-46 (1984); C. E. Scott et al, Amer. Ceram. Soc. Bull. 61 (5), 579-581 (1982). Binders which would have less sensitivity to moisture, without loss of cohesive strength, would clearly be advantageous.
In summary, a preferred binder for ceramic powders would be soluble in water and a wide range of organic solvents. This ideal binder would be suitable for all ceramic powders and form easily spray-dried mixtures, be compatible with all dispersants and even function itself as a dispersant. It would allow pressing to maximum density with minimal pressure and eject easily from the die. Springback would not occur. It would not require a separate plasticizer or be sensitive to atmospheric moisture. The ideal binder would not leave any deleterious residues during the burn out and firing.
Although poly(ethylene oxides) or poly(ethylene glycols) are commonly used as a binder for ceramics in industry, they have some deficiencies. The use of poly(ethylene oxides) is generally limited to aqueous processes where they produce slurries of high viscosity. They have solubility only in methanol and methylene chloride at ambient temperature. These two solvents are very low boiling and toxic.
Poly(2-ethyl-2-oxazoline) is more expensive than the polyethylene glycol-type resins. It has as an advantage a low molecular weight which gives rise to low aqueous system viscosities. A deficiency of this resin is its high Tg (70 C) which is too high for normal processing and must therefore be admixed with a plasticizer (PEG 400). This polyether however renders poly(2-ethyl-2-oxazoline) formulations hygroscopic. Poly(vinyl alcohol) also requires plasticizing.
The various acrylic latex type binders produce very desirable low viscosity slips. The dried powders, however, are very hard and do not press well.
Aluminum oxide (alumina) is by far the most widely used powder in technical ceramics. Zirconium oxide (zirconia), beryllium oxide (beryllia), and other oxides are used in special applications as are the non-oxides, silicon carbide and silicon nitride.

Ethylene oxide/propylene oxide block copolymers as green binders for ceramics


An active filter circuit includes a first and second differential pairs each having a pair of transistors. A capacitor is connected to a collector of one transistor from each of the first and second differential pairs. A first and second negative feed-back paths are connected, respectively, between the collector and a base of one transistor of the first differential pair and between the collector of one transistor of the second differential pair and a base of the other transistor of the first differential pair. By applying suitable voltages to respective inputs of the differential pairs, the active filter circuit functions as a band-pass filter, lowpass filter, high-pass filter, band elimination filter or phase-shifting filter with the same circuit configuration. A current mirror circuit correlatively changes current amounts of the first and second differential pairs in response to a control voltage, whereby a filter characteristic can be changed.

1. Field of the Invention
The present invention relates to an active filter circuit. More specifically, the present invention relates to an active filter circuit suitable for an integration circuit (IC).
2. Description of the Prior Art
In a case where a filter is to be incorporated in an integrated circuit, due to variations of elements in the IC, a fluctuation takes place in a filter characteristic. Conventionally, in order to compensate for such a fluctuation, there was one method in which a dummy reference filter is provided in the IC and a reference signal is input thereto, and a feed-back control is applied to the reference filter so that a value of an output of the reference filter becomes a desired value. Based upon an idea that since a filter to be controlled comprises resistors and capacitors being the same as or correlative to that of the reference filter and therefore, a filter characteristic of the filter to be controlled can be adjusted to the same as or correlative to the characteristic of the reference filter if and when the same or correlative control signal is applied thereto, this method is a method for controlling the other filter to be controlled within the IC.
A prior art shown in FIG. 1 is one example of a case where a cut-off frequency fc of a lowpass filter is automatically controlled. First, a reference signal having a predetermined reference frequency Fref is input to a reference filter, and a level of a signal that is obtained by amplifying an output of the reference filter is compared with an output level of a reference frequency signal oscillator, a control voltage Vc by which both the levels are become coincident with each other is out, and the control voltage is applied to a variable capacitance diode Cv so that the filter characteristic is changed. By applying this feed-back control, when an attenuation amount at the reference frequency in the filter becomes equal to a gain of the amplifier, both levels becomes equal to each other and thus the filter is brought into an adjusted state.
In the conventional method shown in FIG. 1, it is not necessary to apply a signal externally to adjust the filter incorporated in the IC; however, since a dummy reference filter is to be provided in the IC, not only the number of elements in the IC increases but also the reference signal oscillator is needed.
One example of a filter circuit suitable for an IC is disclosed in, for example, Japanese Patent Publication No. 61-55860 published on Nov. 29, 1986.
In a filter circuit disclosed in Japanese Patent Publication No. 61-55806, in order to implement a high-pass filter circuit, it is necessary to add a subtracter, and therefore, there was a problem that not only the number of circuit components increases but also a circuit configuration becomes complex.