Silicone material crosslinkable into silicone elastomer by polyaddition reactions is described. A material is provided offering a compromise between the following characteristics: fluidity (in non-crosslinked state), hydrophilicity (in non-crosslinked or crossliked state) and high mechanical properties (in crosslinked state). The following materials are added to crosslinkable silicone material: (i) a reinforcing siliceous filler in the form of a suspension obtained by subjecting the filler to a treatment in two stages by an agent providing compatibility and by operating in the presence of a polyorganosiloxane with Si-alkenyl functions; and (ii) one or more non-ionic, ionic or amphoteric surfactants. Said silicone material is particularly useful for impressions, for example dental impressions and for making pads used in pad printing techniques.

The field of the present invention is that of the silicone materials comprising a polyorganosiloxane (POS for short) composition, which can be crosslinked or cured into a silicone elastomer by polyaddition reactions, and a wetting agent allowing a hydrophilic character to be conferred on the said material. The applications intended for such systems are, especially, the taking of impressions and, more particularly, the taking of dental impressions within the context of producing dentures. The expression xe2x80x9ctaking of impressionsxe2x80x9d is understood to mean, in the present text, not only the operations of taking impressions of whatever object and of whatever shape, in order to produce a model made in particular of plaster, but also the operations of reproducing or duplicating models made in particular of plaster. The expression xe2x80x9ctaking of dental impressionsxe2x80x9d is understood to mean, in the present text, not only the operations in which dental impressions are taken in the mouth in order to obtain precise copies of jaws or parts of jaws which may or may not bear, totally or partly, teeth and to form plaster models, but also the duplicating operations in which plaster models of jaws or parts of jaws are reproduced in a laboratory for dentures. The intended applications also encompass, in particular, the manufacture of pads, such as those used in pad printing techniques.
The subject of the present invention is also a process for preparing the hydrophilic silicone elastomer material. The subject of the invention is also the use of the said material for taking impressions, for example dental impressions. Finally, the subject of the invention is the use of the said material for the manufacture of pads, such as those used in pad printing techniques.
Silicone materials are widely used in these fields. This is partly due to the fact that silicone materials exhibit, on the one hand, a great diversity of chemical, mechanical and physical characteristics and, on the other hand, non-toxic, non-irritant and non-allergenic behaviour. Furthermore, silicone materials constitute poor substrates for the cultivation of microorganisms, thereby giving them remarkable properties with regard to hygiene.
The POS compositions of interest within the context of the present invention comprise at least:
a POS(1) composition carrying Si-alkenyl functional groups which are capable of reacting by addition reactions with the Sixe2x80x94H crosslinking functional groups of a POS(2) composition;
a POS(2) composition carrying Sixe2x80x94H functional groups which are capable of reacting with the Si-alkenyl functional groups of the POS(1) composition;
optionally, an unreactive POS(3) composition, differing from the POS(1) and POS(2) compositions, which can be used as a diluent;
a catalyst for catalysing the polyaddition reactions; and
a particulate reinforcing mineral filler, generally of a silicious nature, treated with a compatibilizing agent, based especially on an organosilane or on an organosilazane, and optionally a semi-reinforcing or bulking filler.
It is known that such POS compositions, which advantageously may be in the form of two components, are crosslinkable or curable at room temperature and are particularly beneficial in the field of taking impressions, in particular dental impressions, since these compositions are endowed with flow and film-forming properties before crosslinking, making it possible to take an impression of whatever shape with excellent reproduction of the details. Moreover, these compositions can crosslink by polyaddition reactions in a few minutes at room temperature; in addition, they are non-toxic and satisfy the European pharmaceutical regulations. The crosslinking, which results in the hardening of the silicone composition, makes it possible to form moulds made of elastomers having mechanical properties, dimensional stability and thermal resistance which all comply with the desired specifications.
However, compositions for impressions based on silicone crosslinking by polyaddition reactions are intrinsically hydrophobic. Thus, when the mixed moulding compound is applied to the wet surface of teeth and gums, there may therefore be a casting defect or insufficient penetration into the hollows of the gums because of the presence of liquid residues; after crosslinking, the reproduction is therefore defective. Moreover, during the operations of duplicating the positive of the plaster impression, refractory plaster of hydrophilic character has to be poured into a mould made of hydrophobic silicone; there may be occlusion of small air bubbles because of the incompatibility between the surfaces, this occlusion resulting in defective reproduction.
These drawbacks may be practically eliminated by giving the intrinsically hydrophobic POS compositions a hydrophilic character by the use of various surfactants; thus, it has been proposed to use: in U.S. Pat. No. 4,657,959, a polyorganosiloxane with polyether functional groups; in U.S. Pat. No. 4,691,039 and U.S. Pat. No. 4,752,633, an ethoxylated silane; in U.S. Pat. No. 5,064,891, a polyorganosiloxane with polyol functional groups; in EP-A-0,480,233, a poly(alkoxylated) fatty alcohol; and, in FR-A-2,600,886, a water-soluble protein combined if necessary with a nonionic surfactant.
Continuing research in this field of the art, the Applicant has found:
that the introduction of one or more surfactants into a polyaddition POS composition, containing a filler consisting, entirely or partly, of a treated reinforcing mineral filler,
results in the development of a thixotropic character, that is to say in a significant increase in the viscosity of the silicone material in the uncrosslinked state comprising, as constituent elements, the POS composition and the surfactant(s); the silicone material consequently becomes insufficiently flowable and this drawback is of the kind to cause considerable trouble in the operations of taking impressions and to degrade the quality of the reproduction of the details.
This thixotropy phenomenon, connected with the introduction of surfactant(s) into the POS compositions with treated reinforcing mineral fillers, manifests itself particularly adversely in the case of silicone materials whose content of treated reinforcing mineral filler is high, for example equal to or greater than about 15% with respect to the weight of the silicone material. This limit of about 15% can be lowered to about 10% when the silicone material also includes a semi-reinforcing or bulking filler in an amount of 10% to 30% with respect to the weight of the silicone material.
It has now been found that it is possible to get round this difficulty by using, for preparing the silicone material, a particular treated reinforcing mineral filler, which is in the form of a suspension obtained by carrying out a two-stage treatment of the filler with a compatibilizing agent (CA for short) and by performing this treatment in the presence of at least one portion of the POS(1) composition carrying Si-alkenyl functional groups.
The combination of the use of the reinforcing mineral filler treated in a particular way, indicated above, and the use of one or more surfactants results in a polyaddition silicone material, especially one that can be used for taking impressions, providing a compromise between the following desired characteristics: fluidity (in the uncrosslinked state) and hydrophilicity (both in the uncrosslinked and the crosslinked state) and high mechanical properties (in the crosslinked state).

Hydrophilic silicone elastomer material used in particular for impressions


Dynamic templates include regions that provide behavior based upon a purpose or desired outcome. Templates and regions can modify the logical representations associated with objects to create semantic context for the objects. Templates and regions can also generate visual representations of objects based upon their logical representations. The visual representation utilized by a template or region can be selected manually or based upon the capabilities of a computing device. Objects contained within regions can be sorted, filtered, arranged, and projected based on their associated logical representations. Templates and regions can modify their size based upon the objects contained therein, can receive logical representations of objects from data sources and update the data sources to reflect modification of the logical representations, can initiate actions based on changes to the logical representations associated with objects, and generate structured summaries or other types of content based upon the logical representations.

Whiteboard applications enable users to place content on a canvas in a free-form manner. For example, users participating in a whiteboard sharing session might be permitted to draw freely on a canvas using digital ink. However, although such applications provide a great deal of freedom for creating and sharing content using a free-form digital canvas, these applications also suffer from a number of drawbacks.
One drawback of current whiteboard applications stems from the unstructured nature of a whiteboard canvas. In particular, because a whiteboard canvas is free-form, it can be difficult for users to create context and draw meaning from content on such a whiteboard. For example, users in a whiteboard sharing session might write a list of to-do items on a whiteboard canvas using digital ink. Digital ink on a whiteboard canvas does not, however, have any semantic context and, therefore, cannot be operated on such as, for example, by sorting or grouping the to-do items. In order to add semantic context to the to-do items, a user typically has to transcribe the digital ink and manually create to-do items from the transcribed text, which can take time, be error prone, and consume significant computing resources.
Some whiteboard applications attempt to add context to whiteboard content by presenting static images that can be used as guidelines for creating and managing content. Static images, however, only provide visual cues and do not provide any semantic context. As a result, users still might have to transcribe digital ink and create to-do items, or other types of contextual items, from the transcribed text which, as mentioned above, can take time, be error prone, and consume significant computing resources.
It is with respect to these and other technical challenges that the disclosure made herein is presented.

This patent is subject to a terminal disclaimer.


The present invention relates to a formulation comprising at least one thermoplastic polyurethane polymer and a flame retardant composition, the flame retardant composition comprising                i) at least one metal or metalloid oxide particle selected from magnesium oxide, magnesium hydroxide, silicon oxide, or aluminium oxide;        ii) at least one phosphate component selected from the group comprising ammonium polyphosphate (APP), melamine phosphate, melamine pyrophosphate and melamine polyphosphate or mixture thereof, and        iii) at least one oligomeric phosphate ester.

Thermoplastically processable polyurethane—which will be referred to as TPU below—is a material that has proven successful as a sheath material in the cable industry due to its excellent properties. The material is highly abrasion resistant, has high thermal stability, and can be made flame-resistant to self-extinguishing by adding certain materials. Cable sheaths made of polyurethane exhibit resistance to cutting, initial tearing, and tear propagation. In addition, polyurethane is or can be formulated to be resistant to ozone, microbes, oil, and high-energy radiation. Cables equipped with a polyurethane sheath are extremely flexible and can withstand high numbers of bending cycles over tight radii.
However TPU has a mostly undesirable characteristic in that it forms a relatively thin melt at elevated temperatures. In case of fire, this has the effect that the liquid material drips off and the cable core is thus exposed. At extremely high temperatures, the materials added to improve flame-resistance are frequently inadequate, and burning or hot material drips and, under some circumstances, ignites other material, thereby causing a rapid expansion of fire.
It is an object of the present invention to provide a formulation comprising at least one TPU, which formulation has less tendency to drip or even does not drip in case of fire and has excellent flame retardancy.

Flame retardant composition for thermoplastic polyurethane polymers


The present invention relates to a lid for an integrated circuit. According to one embodiment, an integrated circuit having a lid comprises a substrate having a flat surface and extending a first length and a lid having a recess and a foot portion. The lid generally has a second length shorter than the first length, and is positioned on the flat surface of the substrate. Finally, a bonding agent is positioned on the flat surface adjacent the foot portion of the lid. According to an alternate embodiment, a second component is positioned on the substrate outside the foot portion, and an adhesive seal is positioned on the substrate adjacent the foot and covering the component. A method of securing a lid to an integrated circuit is also disclosed.

Heat sinks are used in a variety of electronic devices to dissipate heat from the device, preventing any failure of or damage to the device. Heat sinks are made of a variety of heat conducting materials and are formed in a variety of shapes to adequately conduct the heat from the device. More specifically, heat sinks, also commonly called lids, are used with integrated circuits to reduce the heat of the semiconductor die to enable the integrated circuit to function properly. The purpose of the lid is to keep a semiconductor junction, such as a junction of the transistor, below a maximum specified operating temperature. Another purpose of the lid may be to provide some physical protection for the components within the lid. A lid for an integrated circuit, commonly made of a metallic or ceramic material, is attached on top of a flip chip package to provide protection to the silicon die and other discrete surface mount components and to increase thermal conductivity of the package.
However, these types of lid heat sinks often exhibit the problem of separating from the top of an integrated circuit package. Because the adhesion strength of the adhesive used to attach the conductive lid is sometimes not strong enough to hold the conductive lid to the package, the conductive lid can come off of the package. Proper material construction and processing of the lid, the package, and the adhesive is required so that the lid will stay attached to the package during the assembly and long term field usage. Degradation of adhesion can be caused by many factors, including improper dispensing of adhesive that does not produce full adhesive surface as designed, shear stresses induced due to thermal expansion/shrinkage differences at the interfaces, push/pull stresses induced due to warping of the silicon, package, and/or board, adhesive degradation due to chemical attack, etc. Excessive component handling stresses, such as excessive torque or pressure during test, assembly, or rework, can also result in separation of the lid from the package.
Currently, a wide variety of components, such as FPGA, ASIC, graphics, microprocessors, etc., employ flipchip ball grid array (BGA) packages. As the requirements for large size silicon chips and/or passive devices used on packages increase, a smaller bond area is used to bond the lid to the substrate. However, the smaller bond area even further reduces adhesion of the lid to the substrate, often leading to lid delamination when subjected to post assembly thermal and mechanical stresses. Also, conventional designs having smaller bond areas can lead to the misalignment of the lid with respect to the substrate during lid assembly. Finally, conventional lid designs can have gaps in the epoxy bead, permitting moisture, solvents and cleaning solutions to enter the package. Such gaps can result in contamination of the thermal grease that conducts heat from the back of the die, possibly impacting the functionality of the device.
Accordingly, there is a need for an improved lid for an integrated circuit and method of securing a lid to an integrated circuit.

Integrated circuit having a lid and method of employing a lid on an integrated circuit


A method of analyzing cyber-security risks in an industrial control system (ICS) including a plurality of networked devices includes providing a processor and a memory storing a cyber-security algorithm. The processor runs the cyber-security algorithm and implements data collecting to compile security data including at least vulnerability data including cyber-risks (risks) regarding the plurality of networked devices by scanning the plurality of devices, processing the security data using a rules engine which associates a numerical score to each of the risks, aggregating data including ranking the risks across the plurality of networked devices and arranging the risks into at least one logical grouping, and displaying the logical grouping(s) on a user station.

Computer systems are used in performing a variety of different tasks. For example, an industrial network of computer systems and equipment are used in controlling and/or monitoring industrial systems termed industrial control systems (ICS). Such ICS can be used in connection with manufacturing, power generation, energy distribution, waste handling, transportation, telecommunications, oil refining, and water treatment. The ICS may be connected and accessible via other networks, both directly and indirectly, including a corporate network and the Internet.
The industrial network may thus be susceptible to both internal and external cyber-attacks. As a preventive measure from external cyber-attacks, firewalls or other security measures may be taken to separate the industrial network from other networks.
In an ICS, cyber-security is of increasing concern, and it is generally difficult to quickly determine the potential sources of cyber-risk to the whole system. Modern ICS generally contain a mix of equipment including WINDOWS servers and workstations, switches, routers, firewalls, safety systems, proprietary real-time controllers and field devices. Often this equipment is a mixture of equipment from different vendors.
Moreover, ICS operators may not have a complete understanding or inventory of all the devices/equipment running in the ICS. Unaddressed security vulnerabilities in any of this equipment can disrupt production or cause unsafe conditions in the ICS. Such system failures may be the result of a malicious attack, a disgruntled employee, a virus, or just the result of a mistake coupled with a lack of cyber-security measures. Even stand-alone equipment can be vulnerable, as viruses can be introduced directly via Universal Serial Bus (USB) memory "sticks".

Analyzing cyber-security risks in an industrial control environment


A random access mailbox has a stack of horizontally extended trays for receiving sheets of paper supplied from a printer. A modular construction provides a sheet transport system including gates to deflect sheets into a selected tray from sheet feeding rollers incorporated in the modules for carrying sheets through a sheet path defined between the rollers and pressure applying rollers to the respective gates which can be actuated randomly to deflect a sheet from the rollers into a selected tray between cooperative modules. A sheet detector is provided at each gate along the feed path to detect the presence of a sheet at any location along the feed path. The gates or deflectors nest or overlap vertically to reduce overall height of the apparatus and provide continuity to the sheet guide surfaces.

In the use of computer controlled printers it has become desirable that the output from the printer be collected in sorter trays to separate multiple copies of a job. In addition, particularly in the case of networked printers, it has become desirable to be able to separately collect different jobs in the sorter trays in the manner of a mailbox, so that the jobs or work output for different users may be isolated from one another.
It also has become desirable that the separate jobs which may be of a sensitive nature may be secured against unauthorized access, so that locking mailbox type sorter constructions have evolved.
Printers which operate at relatively high speeds of, say, 40 pages per minute are faster and generally with small gaps between pages or between the last page of one job and the first page of another job, may require truly, almost instantaneous, random access to different trays. Sheet sorting or collating machines of the type using instantaneously and selectively operable means for deflecting sheets from the sorter sheet transport to the selected trays are preferably employed for such high speed printers.
Examples of such sorters are shown and described, for example, in my prior U.S. Pat. Nos. 3,937,459 and 4,691,914.
In the case of U.S. Pat. No. 3,937,459, a series of vertically spaced gates are arranged to be actuated by solenoids to deflect sheets from a vacuum plenum type transport, into the trays which are arranged in a vertical stack. The only speed limitation on such a sorter and other so-called fixed bin, gate type sorters is the time required for the gates to move from a normal sheet guiding position to a sheet deflecting position, so that such sorters are very well suited to use as true random access mailboxes, as referred to above. In addition, the gates are of nesting construction to reduce the overall height of the apparatus while providing a guide for sheets passing the gates.
In the case of U.S. Pat. No. 4,691,914, the sheet path is defined by opposing sets of rollers carried by a modular stack of sheet transport units, and a solenoid operated nip roller is moved to a position cooperative with one of the fixed rollers to divert or deflect a sheet into a selected tray. Such a sorter construction is more simple in construction than the sorter of U.S. Pat. No. 3,937,459 and lends itself to selecting the number of trays and the height of the assembly due to its modular construction. Again, such a sorter is applicable to relative high speed printers because it can be randomly operated substantially instantaneously.
Another prior sorter useful with high speed printers is shown in U.S. Pat. No. 4,881,730. In this construction the sorter employs a combination of sheet transport rollers and pivoted gates to deflect sheets from the transport rolls to the trays.
As shown in U.S. Pat. No. 4,111,410 vertically spaced sets of feed rollers transport the sheets to the tray entry space and gates are opened to deflect sheets from the rollers, while the sheet inlet ends of the trays are held spaced apart to increase the inlet space.
These types of sorters referred to above are inherently expensive, due to the numbers of components and the size of the sorter assemblies required to sort or collate the output of sheets from a source machine, either sequentially or randomly. However, such sorters are fast because they eliminate the time delays inherent in sorter devices of the types employing travelling infeeds, as exemplified in my U.S. Pat. No. 4,843,434 or travelling deflectors, as exemplified in Snellman U.S. Pat. No. 3,372,922, dated Mar. 12, 1968, or travelling sheet gripping infeeds, as exemplified in U.S. Pat. No. 4,881,730, or the lockbox sorter disclosed in the application of Coombs and Billings, U.S. Ser. No. 849,233 (owned in common herewith) in which the gates are selectively operable by an indexed actuator which also can release a lockbox. These latter types of sorter devices are not as well suited for high speed printer mailboxes because of the time delay required to provide for transfer of a sheet to different bins.

Sorter having pivotable diverter gates with nip rollers and diverter module assembly therefor


Aspects of the invention relate to circuit topology recognition and circuit partitioning. In various embodiments of the invention, diode-connected transistors can be identified in a circuit netlist based on the unique structure. From the diode-connected transistors, current mirrors can be found. The current mirrors may be employed for locating differential pairs used in the input stage of operational amplifiers and for locating supply voltage and ground nodes in the netlist. The subcircuits that are strongly connected due to feedback loops of operational amplifiers in the circuit can then be identified and grouped together for circuit analysis and simulation.

Transistor-level circuit simulation is important for designing integrated circuits. Simulating a circuit's behavior before actually building it can greatly improve design efficiency by making faulty designs known and providing insight into the behavior of electronics circuit designs. A circuit simulator formulates circuit equations and then numerically solves them to compute the circuit response to a particular stimulus. Developed about forty years ago, SPICE (Simulation Program with Integrated Circuit Emphasis) simulators are still being widely used in part due to its precision. While offering superior precision, SPICE simulators are limited to the simulation of small subcircuit blocks because of their memory capacity requirements and performance limitations.
The Fast-SPICE simulators have been developed to address these limitations. One of the main approaches adopted by the Fast-SPICE simulators is breaking a circuit into smaller subcircuits and solving each subcircuit independently. Further, if the signals in one or more subcircuits are latent during an interval of time, then it is not necessary to solve for them during that interval of time. These techniques, however, rely upon assumptions such as those about signals between the subcircuits. The assumptions may turn out to be incorrect if the circuit is not partitioned correctly. Thus, how a circuit is partitioned affects the accuracy of Fast-SPICE simulation.
While automatic circuit partitioning has been developed for the relatively simple circuit topologies found in digital MOS (metal oxide semiconductor) circuits, it remains a challenge for analog and mixed-signal circuits. FIG. 2 illustrates an example of an operational amplifier 200 being partitioning by a conventional automatic circuit partitioning method. In FIG. 2, the operational amplifier 200 is broken into several subcircuits by the conventional automatic circuit partitioning method. Only subcircuits 220, 240 and 260 are shown. Like many operational amplifiers, the operational amplifier 200 has a negative feedback loop 280. It should be appreciated that one or more subcircuits outside an operational amplifier may also be in the feedback loop for the operational amplifier. The feedback loop make all the subcircuits in the feedback loop such as subcircuits 220, 240 and 260 in FIG. 2 strongly coupled so that they are required to be simulated as a whole. Without identifying the feedback loop, a conventional automatic circuit partitioning method breaks an operational amplifier and its feedback into several subcircuits for simulation, thereby resulting in incorrect simulation results. It is thus desirable to find an efficient method for identifying operational amplifiers and their feedback loops in a transistor-level netlist.

Circuit topology recognition and circuit partitioning


The invention relates to an optical fiber sensing device (1) for sensing the distribution of the compression/deformation of a compressible/deformable element (2), comprising: an incompressible/undeformable tubular element (3) with a recess (4) extending in a length direction (X) thereof, the recess being enclosed by the tubular element, an optical fiber (5) arranged in the recess, comprising one or more light distortion structures (6), and being expandable in the length direction of the recess, one or more expandable elements (8), having a higher compressibility/deformability than the tubular element in a transverse direction (Y), arranged at one or both ends (9) of the tubular element, the optical fiber being enclosed in the expandable elements, which are arranged for expanding/contracting in the length direction, along with the optical fiber, when the expandable elements are subjected to a transverse load (F).

Such optical fiber sensing devices are known from the prior art. For instance, U.S. Pat. No. 7,405,818 B2 discloses a seal for preventing leakage of fluid from between a first member and a second member has a seal body and a seal wear indicator. The second member is capable of moving toward and away from the first member. The seal body is adapted for engaged contact with the first and second members so as to prevent leakage of fluid as long as the seal has not worn beyond a specified depth. A seal wear indicator is positioned within the seal body at approximately the specified depth, such that when the seal has worn to the specified depth, a change in the optical conductor is detected, indicating that the seal needs replacement.
U.S. Pat. No. 5,684,297 A discloses a method of detecting and/or measuring changes in a physical magnitude by means of a distributed sensor, wherein changes are detected and/or measured at a plurality of "measurement" points along the sensor. The sensor comprises an optical fiber having an optical core for guiding the majority of light waves, wherein the optical core includes a plurality of diffraction gratings distributed along said optical fiber. The diffraction gratings are each situated at one of the measurement points and all have substantially the same central reflection wavelength in the absence of strain.
Furthermore, from public prior use so-called "intelligent gaskets" are known using optical technology incorporating light distortion structures, such as fiber Bragg gratings (FBG's), for usage, condition and integrity monitoring, as well as state determination, of gaskets, enabling predictive maintenance, for instance at places where pipes are connected, in order to prevent leakages, spillage, and other forms of uncontrolled pollution.
A problem with the known optical fiber sensing devices, however, is that it is very difficult to accurately measure the amount of compressive force being exerted on the optical fiber (cable). The optical sensing devices according to the state of the art in practice can only sense that some change in pressure on the optical fiber has occurred due to a shift in the wavelength reflected by the light distorting structure or by a change in the state of polarization caused by non-radial deformation of the light distortion structure, both being observed by a light sensor as a result of compression or deformation of the light distortion structure.
A further problem with the known optical fiber sensing devices is that it is next to impossible to verify the direction of the compressive forces being exerted on the optical fiber. The known optical fiber sensing devices merely sense that there is some radial force being exerted on the optical fiber, but not from which (angular) direction the force is applied. However, such information is highly critical for predicting the integrity and possible failure of the compressible or deformable element, in particular when the compressible or deformable element is a gasket.

Optical fiber sensing device for sensing the distribution of the compression or deformation of a compressible or deformable element


A Personal Digital Assistant (PDA) printer and printing method. The printer includes a user interface that allows a user, through a display, to select a fax note which is stored in memory, insert/remove fax headers, set margins, and input fax transmission instructions. The printer includes a memory that stores fax notes fax header insertion/removal instructions, and fax note margin instructions. The printer also includes a processor that initializes a fax modem and sets an environment for fax transmission to a receiving fax machine upon input of the fax transmission instructions. The processor also inserts and removes a fax header based on information stored in the header information flag when fax transmission is ready, reads fax header data and the fax note and margin information and generates bit map image data. The processor also converts the bit map image data into a data format for fax transmission, transmits the data converted by the data format converter, and terminates fax connection when data is completely transmitted.

1. Field of the Invention
The present invention relates to a personal digital assistant (PDA), and more particularly, to a PDA printer and a printing method containing a display capable of displaying characters and graphic data, a fax modem capable of transmitting and receiving fax data, and a memory capable of storing data.
2. Description of the Related Art
As society becomes more complex and diversified, user demands for data communication services also become diversified. These demands have been satisfied through developments in data communication technology. In this context, the PDA has emerged. The PDA, serving as a portable computer, fax, and electronic pocket book, is so named because it provides personal and multimedia services which incorporate recent data communication technology. The PDA enables a user to easily access a small and portable terminal using a pen or voice, instead of a conventional keyboard, and provides a graphic user interface (GUI) environment. In addition, the PDA serves as a notebook computer which allows external communication.
Data communication, including Internet connection, PSTN connection to an information media like UNITEL, and fax communication, has recently become the most significant function of the PDA.
Generally, PDA fax transmission is performed by means of a simple note made on a memo pad included in the PDA. In a conventional PDA, a note is printed by direct connection to a printer or by using fax transmission. However, the former method requires a driver program for driving the printer, which results in development constraints upon the driver program and portable printer. Therefore, the latter method is used.
However, because the purpose of conventional fax transmission is simply to transmit a note by fax, it is inconvenient to transmit a formal document and utilize fax transmission for printing. Header output such as reception time, fax number, and page number on the upper portion of a fax note creates inconvenience to a user.

Personal digital assistant (PDA) printer apparatus and printing method


A system adapted to regulate pressure of a flow of breathable gas generated by a motorized blower fan. The system may include a flow estimation analyzer adapted to receive a speed signal representative of a speed of the fan and estimate a parameter representative of the flow of breathable gas (e.g., a flow rate of the breathable gas). The parameter may be determined by inputting the speed signal into a function (e.g., an equation, matrix, or lookup table), which may be selected from a plurality of predetermined functions. The predetermined function may be selected based upon a specific characteristic of the speed signal as identified at the time of estimation of the parameter representative of flow.

Positive airway pressure (PAP) therapies are frequently used in the treatment of, among other ailments, obstructive sleep apnea, complex sleep apnea, asthma, bronchitis, chronic obstructive pulmonary disease (COPD), snoring, and congestive heart failure. These therapies typically provide a flow of pressurized gas (e.g., typically air, but may be most any gas or gas-vapor mixture including, for example, oxygen and medicinal vapors) to pressurize the airway of a user to a pressure in the range of 4-30 centimeters (cm) of water (H20) (e.g., often about 4-20 cm H20) or more. Depending upon the particular therapy, a variable or a constant pressure therapy may be administered to the user to reduce or eliminate airway occlusions (or to otherwise treat acute or chronic respiratory failure) that necessitated the use of the therapy. For instance, continuous positive airway pressure (CPAP) may provide a generally continuous pressure throughout the user's breathing cycle. Bi-level positive airway pressure (Bi-PAP) may provide a variable pressure in coordination with the user's inspiration and expiration efforts. In more advanced systems, auto-titration positive airway pressure (Auto-PAP) may regulate the therapy apparatus based on the level of breathing assistance the user may require at any given point during therapy. Still further, adaptive servo-ventilation may be used to treat complex sleep apnea syndrome, which can be identified when central apneas or periodic breathing occur during a reduction of obstructive events with positive airway pressure.
Regardless of the particular therapy, positive airway pressure apparatus typically includes at least a blower unit and a mask. A delivery hose may also be included to connect the blower unit to the mask, wherein the hose and mask may together define a delivery conduit between the blower and the user. The blower unit may rest on a bedside table or floor adjacent the bed (or in the bed), or alternatively, may attach to the user. The blower may typically include a fan or impeller connected to an output shaft of a motor. A controller regulates the motor to control fan speed and thus therapy pressure. The mask is configured to be secured relative to the user's head in such a way as to form a generally air-tight seal with the user's airway. As a result, the fan may generate a flow of pressurized gas that is delivered to the airway via the delivery conduit.
To control the pressurized gas, pressure within the system is typically monitored (e.g., via a pressure sensor or transducer located near the outlet of the blower or in the mask) and regulated by the controller in a way that maintains a desired pressure profile during breathing.
As those of skill in the art may appreciate, it is sometimes beneficial to accurately measure flow of the pressurized gas to or from the user during therapy. Monitoring (and potentially storing data regarding) flow parameters may, for example, assist in: detecting unintentional mask leaks; monitoring user compliance; detecting transitions between inspiration and expiration (e.g., for Bi-PAP); and otherwise detecting breath anomalies such as apneas and hypopneas.
Typically, flow is measured by a pneumotachometer (i.e., a differential pressure transducer measuring pressure difference across a flow restriction) located within the delivery conduit. Electrical signals representing flow may then be transmitted to the controller. While effective, such flow measuring transducers can increase the overall size, cost, and complexity of the positive airway pressure apparatus.

Systems and methods for estimating flow in positive airway pressure therapy


Systems and methods for establishing a bridge between two documents on a server are provided, including receiving, at the server, a first document represented by a hierarchical data structure model having a plurality of first nodes, generating, by a processor, a second document represented by a flat data structure model having a plurality of flat data structure elements, and establishing, by the processor, the bridge between the first document and the second document. Establishing the bridge includes linking each of the plurality of first nodes to the plurality of flat data structure elements, and maintaining the bridge, such that an edit to the first document, represented in at least one of the first nodes, is applied to at least one corresponding flat data structure element, thereby applying the edit to the second document.

During development of an electronic document, it is often desirable to have multiple reviewers propose changes to and comment on a draft of the electronic document. For example, an author may create an initial draft of an electronic document and send a copy of the electronic document to multiple reviewers for revisions and comments. Common document models do not allow multiple users to simultaneously edit an electronic document. Instead, each reviewer may independently propose changes or make comments in the electronic document and return a revised version of the electronic document back to the author. However, since the reviewers cannot see each other's revisions, each of the reviewers creates a unique version of the electronic document, each of which may include conflicting changes. The original author will resolve the conflicting changes and may re-send updated copies of the electronic document to the reviewers. These steps are repeated until the author and all of the reviewers are satisfied with a version of the electronic document.

Method for adding real time collaboration to existing data structure


An apparatus and method for construction of scaffold structures having improved safety characteristics. In various embodiments, the apparatuses comprise a set of structures, including connecting rails, fencing, gates, and ladders. The structures are adapted to be used with locking-cup type scaffold designs. In one embodiment, the apparatus comprises a scaffold joint comprising a vertical post comprising first and second joint sections. At least one structural brace is disposed within the joint sections having a mounting flange disposed at an angle to the principal axis of the structural brace.

The present invention relates generally to the field of construction scaffolding, and in particular to a system of scaffolding incorporating a set of features designed to improve both the functionality of the scaffolding and the safety characteristics thereof.
In various applications, scaffolding is erected in order to give workers access to elevations above ground. For example, in the course of repairs to the outside surface of a building, modifications of the same, window washing, painting, cleaning, or installation of siding on the exterior of a building, scaffolding is commonly used to enable workers to move up and down adjacent the side of the building. Such devices are well known and take a wide variety of forms. One of the more conventional forms of scaffolding ordinarily includes one or more vertical posts that are interconnected by cross-braces and which may be stacked on top of each other to permit workmen to work at high elevations.
The scaffold platform typically includes a pair of metal side rails held in parallel spaced relation by a series of spaced transverse hollow rungs upon which metal or wooden planks are placed and secured to provide the floor of a work platform. These rungs may be round, or may have a square cross-section to provide flat upper surfaces upon which the wooden planks may rest and be supported. In order to provide workers access to multiple levels of the scaffolding, most scaffold installations incorporate ladders either integrally as part of the scaffold structure, or mounted to the scaffold structure by some form of attachment means.
Traditional scaffolding has been designed to provide workers with ready access to the surface of a flat wall, or to a right-angle corner of a building. Such scaffolding is useful for more traditional rectangular buildings, but such scaffolding has less utility in conjunction with structures having unconventional shapes. For example, round storage tanks present a unique and potentially dangerous problem for conventional scaffolding systems. Linear sections of conventional scaffolding must be brought together using independent clamps to conform to the surface of the tank. Conventional scaffolding is not designed for curved structures, hence, the clamped joints may become loose and create hazardous conditions for workmen.
Other hazards associated with scaffolds are well known. These hazards include loss of balance, slippage, and displacement of the scaffold due to movement of workers on the scaffold, wind, or other environmental factors. In order to protect the workers against falls, safety structures including guardrails and guard walls are often erected from the scaffold platform on one or both sides of the work platform. It is important that such safety structures be easy to assemble and attach to the platform and yet be firmly held in place with a minimum risk of failure.
One of the more popular scaffold construction designs includes a set of vertical columns having dual hemispherical couplers at regular intervals along their lengths. The vertical columns are tied together with horizontal members spanning between the vertical columns. Each end of each horizontal member is designed to mate with one quadrant of a dual hemispherical coupler. With this design, a single coupler can receive up to four horizontal members.
Although this scaffold design has proven to be useful, it has been found to be useful mostly for building scaffolds disposed against a single wall or against a right-angled structure. There has not been a satisfactory solution to the problem of scaffolding with this type of design against structures having diagonal or curved surfaces. Furthermore, although safety restraints and ladders have been developed that can be used in conjunction with this type of scaffolding, existing designs have been found to be heavy, difficult to assemble, or insufficiently compliant with government safety regulations.
The following summary of the invention is provided to facilitate an understanding of some of the innovative features unique to the present invention, and is not intended to be a full description. A full appreciation of the various aspects of the invention can be gained by taking the entire specification, claims, drawings, and abstract as a whole.
The present invention relates generally to the field of construction scaffolding, and in particular to a system of scaffolding incorporating a set of features designed to improve both the functionality of the scaffolding and the safety characteristics thereof. In its various embodiments, the present invention includes a number of novel structures and assemblies to facilitate safe and efficient assembly of scaffolding as well as improve the safety of workers using such scaffolding. In certain embodiments, the present invention facilitates the safe and efficient construction of scaffolding at the corner of structures where two walls meet at an angle greater or less than 90 degrees.
In one embodiment, the present invention includes a structural brace having a center section with a lengthwise axis, a first end, and a second end. A first mounting flange is attached rigidly to the first end, which includes a mounting surface having a center, an upper tab, and a lower tab. A second mounting flange is attached rigidly to the second end, and includes a mounting surface having a center, an upper tab, and a lower tab. The vector normal to the mounting surface at the center is disposed at an angle of between about 5 degrees and about 89 degrees to the lengthwise axis of the center section.
In another embodiment, the present invention also includes a guard rail panel including an upper brace section having a first end and a second end; a lower brace section having a first end and a second end, connected to the upper brace section by a bridging member. A first upper mounting flange, attached to the first end of the upper brace section, includes an upper tab and a lower tab. A second upper mounting flange, attached to the second end of the upper brace section, includes an upper tab and a lower tab. Finally, a first lower mounting flange, attached to the first end of the lower brace section, includes an upper tab and a lower tab and a second lower mounting flange is attached to the second end of the lower brace section, having an upper tab and a lower tab.
In yet another embodiment, the present invention is directed to a ladder assembly comprising a first vertical member, a second vertical member, one or more horizontal rungs connecting the first vertical member to the second vertical member, and one or more ladder mounting brackets. Each ladder mounting bracket has a first and second end, and is connected to a vertical member at the first end by a mounting clamp. The second end of each ladder mounting bracket has a mounting flange having an upper tab and a lower tab.
The novel features of the present invention will become apparent to those of skill in the art upon examination of the following detailed description of the invention or can be learned by practice of the present invention. It should be understood, however, that the detailed description of the invention and the specific examples presented, while indicating certain embodiments of the present invention, are provided for illustration purposes only because various changes and modifications within the spirit and scope of the invention will become apparent to those of skill in the art from the detailed description of the invention and claims that follow.

Scaffolding system having improved safety structures and connecting members


In an embodiment, a method for operating a voltage step-down switched mode power supply includes delivering an output voltage with an output stage having a power transistor that is cyclically made conducting by a first control signal. In PWM mode, the method includes generating an error voltage based on the output voltage and a reference voltage, and applying a first delay on a first control signal. The first delay is determined so as to reduce a difference between the error voltage and the reference voltage.

The PWM or PFM operating mode of a voltage step-down switched mode power supply is generally determined according to an output current and a regulated output voltage level delivered at the output of the switched mode power supply.
Generally, such a switched mode power supply comprises a first transistor referred to as "high-side" and a second transistor referred to as "low-side" or a diode, known to the person skilled in the art as a free-wheeling diode, which are coupled in series between the power supply and ground.
The first high-side transistor is cyclically made conducting by a first control signal and a second low-side transistor is cyclically made conducting by a second control signal.
In pulse width modulation mode, the first and second transistors are alternately made conducting by the first and second control signals.
In pulse frequency modulation mode, the first and second transistors can additionally be made non-conducting at the same time as a function of the first and second control signals.
When a high output current is required in response to a load of the power supply, the power supply operates in pulse width modulation mode and the period/frequency of the control signal is hence fixed.
In this pulse width modulation mode, the power supply is configured to generate via a signal generator circuit of the power supply an error voltage as a function of the output voltage and a reference voltage and to generate via a ramp generation circuit a ramp voltage which increases from zero up to the error voltage so as to determine the duration of the first state of the control signal.
During a light load (i.e., low output current supplied to the load), the switched mode power supply operates in pulse frequency modulation mode and the frequency of the control signal is, as a result, variable.
In this pulse frequency modulation mode, the power supply is configured to generate the ramp voltage and to vary the period/frequency of the control signal as a function of a comparison between the ramp voltage and the reference voltage via a comparator.
It is known to the person skilled in the art that the output voltage of the power supply oscillates strongly at the moment of a transition from pulse width modulation mode to pulse frequency modulation mode or of a transition from pulse frequency modulation mode to pulse width modulation mode if, at that moment, the error voltage and the reference voltage are not equal.
There is thus a need to propose a technical solution that is low in complexity and low in cost, and provides for softening the transitions between pulse width modulation mode and pulse frequency modulation mode and improving the performance of the switched mode power supply.

Method for operating a switched mode power supply of the buck type and corresponding switched mode power supply


An apparatus for generating hydrogen inside of a fuel cell is provided. The fuel cell comprises an anode having at least one inlet and optionally one outlet and, a cathode having at least one inlet and optionally one outlet. An electrolyte is disposed between the anode and the cathode, and a catalyst is provided in a chamber for catalyzing a reaction of a solution comprising a solvent and an at least one chemical hydride dissolved therein to generate hydrogen inside of the fuel cell. A method for generating hydrogen inside of a fuel cell is also disclosed.

The present invention relates to fuel cells. More particularly, the present invention relates to fuel cells provided with a hydrogen generation system.
Fuel cells are seen as a promising alternative to traditional power generation technologies due to their low emissions, high efficiency and ease of operation. Fuel cells operate to convert chemical energy to electrical energy. Proton exchange membrane (PEM) fuel cells comprise an anode (oxidizing electrode), a cathode (reducing electrode), and a selective electrolytic membrane disposed between the two electrodes. In a catalyzed reaction, a fuel such as hydrogen, is oxidized at the anode to form cations (protons) and electrons. The ion exchange membrane facilitates the migration of protons from the anode to the cathode. The electrons cannot pass through the membrane, and are forced to flow through an external circuit, thus providing electrical current. At the cathode, oxygen reacts at the catalyst layer, with electrons returned from the electrical circuit, to form anions. The anions formed at the cathode react with the protons that have crossed the membrane to form liquid water as the reaction product. Additionally, since the reactions are exothermic, heat is generated within the fuel cell. The half-cell reactions at the two electrodes are as follows:
H2xe2x86x922H++2exe2x88x92xe2x80x83xe2x80x83(1)
1/2O2+2H++2exe2x88x92xe2x86x92H2O+HEATxe2x80x83xe2x80x83(2)
In practice, fuel cells are not operated as single units. Rather, fuel cells are connected in series, stacked one on top of the other, or placed side by side. A series of fuel cells, referred to as fuel cell stack, is normally enclosed in a housing. The fuel and oxidant are directed through manifolds to the electrodes, while cooling is provided either by the reactants or by a separate cooling medium. Also within the stack are current collectors, cell-to-cell seals and insulation. Piping and various instruments are externally connected to the fuel cell stack for supplying and controlling the fluid streams in the system. The stack, housing, and associated hardware make up the fuel cell unit.
Various types of fuel cells have been developed employing a broad range of reactants. For example, proton exchange membrane (PEM) fuel cells are one of the most promising replacements for traditional power generation systems. PEM fuel cells comprise an anode, a cathode, and a proton exchange membrane disposed between the two electrodes. Preferably, PEM fuel cells are fuelled by pure hydrogen gas, as it is electrochemically reactive and the by-products of the reaction are water and heat. However, these fuel cells require external supply and storage devices for the hydrogen. Hydrogen can be difficult to store and handle, particularly in non-stationary applications. Conventional methods of storing hydrogen include liquid hydrogen, compressed gas cylinders, dehydrogenation of compounds, chemical adsorption into metal alloys, and chemical storage as hydrides. However, such storage systems tend to be hazardous, dangerous, expensive and bulky.
Other types of fuels have been proposed, including hydrogen-containing materials such as methanol. In some conventional systems, external reformers are employed to liberate hydrogen from the hydrogen-containing materials. The liberated hydrogen is then introduced into the fuel cell. However, the use of external reformers complicates the construction of the system, and results in a substantial loss in system efficiency. In other conventional systems, hydrogen-containing fuels may be supplied directly to the fuel cells, i.e. supplied unreformed to the fuel cell anodes. Once inside the fuel cell, the hydrogen-containing fuel may be directly oxidized or internally reformed, and subsequently oxidized to generate electricity. This occurs in some high temperature fuel cells, such as solid oxide fuel cells. These systems do not require a separate external reformer, and utilize fuels that are easier to handle than hydrogen. However, pure hydrogen typically offers better performance, and is generally more environmentally friendly than most hydrogen-containing fuels. Moreover, high temperature fuel cells operate at a minimum temperature of 600xc2x0 C. These high temperatures are required to reform the hydrogen-containing materials prior to carrying out the fuel cell reactions. As such, hydrogen-containing materials are generally unsuitable for conventional PEM fuel cells that typically operate around 80xc2x0 C.
Another method of generating and storing hydrogen has been recently proposed. This method uses a chemical hydride solution, such as NaBH4, as a hydrogen storage medium. Generally, chemical hydride reacts with water in the presence of a catalyst to generate hydrogen, as shown in the equation below:
NaBH4+2H2Oxe2x86x924H2+NaBO2+HEATxe2x80x83xe2x80x83(3)
The chemical hydride solution acts as both the hydrogen carrier and the storage medium. Ruthenium, Cobalt, Platinum or any alloys thereof may be used to catalyze the above reaction. It is noted that hydrogen is liberated from both the borohydride solution and the water. The borohydride solution is relatively cheap, and is much easier and safer to handle and transport than liquid or pressurized hydrogen. As a result, there are some advantages associated with using borohydride as a method of storing hydrogen as a fuel for use in fuel cells.
There are several conventional hydrogen generation systems that utilize chemical hydrides. One type of hydrogen generation system comprises a closed vessel for mixing chemical hydride powder together with water. The water is introduced into the vessel through an inlet. The vessel contains a mechanical stirring device to ensure adequate contact between the powder and the water, and to prevent the powder from clumping. The hydrogen gas is removed through an outlet in the vessel, and is supplied directly to the fuel cell. These systems tend to be inefficient since the stirring mechanism consumes energy, and increases the overall weight and complexity of the system. Furthermore, the noise generated by the stirring is undesirable. In addition, the reaction rate tends to be low, making the hydrogen generation unpredictable and thus hard to control. The systems also tend to be large and cumbersome.
Another type of hydrogen generation system employs a chemical hydride solution. In this system, an aqueous chemical hydride solution is introduced into a catalyst bed to generate hydrogen for use in fuel cells. However, these chemical hydride systems still require a separate hydrogen generation subsystem for generating and supplying hydrogen to the fuel cell system. As such, the systems tend to be complex, costly, and inefficient.
There remains a need for a fuel cell system that utilizes pure hydrogen and that contains a compact and simple subsystem for generating the hydrogen. More particularly, such a fuel cell system should desirably be equipped to liberate hydrogen from a chemical hydride solution in view of its known properties, and subsequently utilize the pure hydrogen in a fuel cell reaction.
In accordance with the present invention, there is provided a fuel cell stack, comprising:
at least one fuel cell comprising an anode with a fuel inlet port for a hydrogen containing fuel, a cathode with an oxidant inlet port;
at least one chamber for a solution comprising a solvent and at least one chemical hydride dissolved therein, and having a chamber inlet and a chamber outlet for the solution and a catalyst within at least one chamber for catalyzing reaction of the solution to generate hydrogen.
The solution used in the system can comprise a solvent comprising water and an at least one chemical hydride comprising borohydride. The at least one chemical hydride can be in the form of MbxHy, in which M is a metal. Specifically, the at least one chemical hydride can comprise one or a combination of: NaBH4, LiBH4, KBH4, or RbH4. Alternatively, the at least one chemical hydride can comprise NH3BH3. Preferably, the solution comprises a solvent comprising water and an at least one chemical hydride comprising NaBH4 and less than 5% by weight LiBH4. Preferably, the solution further comprises a freezing point depressing agent to ensure the system works properly under low temperatures. Preferably, the freezing point depressant agent comprises glycerol. Preferably, the concentration of glycerol is between 0-5% by weight, and more preferably the concentration of glycerol is 1% by weight. Preferably, the solution further comprises an alkaline additive. The alkaline additive can comprise one or a combination of: LiOH, KOH, and NaOH. More preferably, the alkaline additive comprises 0.1% NaOH by weight.
In accordance with another aspect of the present invention, there is provided an energy system, comprising:
(a) a fuel cell stack capable of generating hydrogen internally and comprising:
at least one fuel cell having an anode with a hydrogen inlet port, a cathode including an oxidant inlet port, and at least one chamber with a chamber inlet port and a chamber outlet port, and a catalyst in each chamber for catalyzing reaction of a solution comprising a solvent and an at least one chemical hydride dissolved therein to generate hydrogen;
(b) a storage means for storing the solution;
(c) a circulation loop, at least connected to the storage means, each chamber inlet port and each chamber outlet port, for circulating the solution from the storage means through the fuel cell stack;
(d) a supplying path, connected to the hydrogen inlet port of each fuel cell anode and each chamber outlet port, for supplying hydrogen generated inside the chamber back to the fuel cell;
wherein the fuel cell stack generates electricity and water from hydrogen and an oxidant.
The energy system can further include a recovery means for recovering the water generated in the fuel cell, and supplying the recovered water to the solution during the reaction as the at least one chemical hydride is consumed in use. Preferably, the recovery means comprises a gas-liquid separator.
In accordance with a further aspect of the present invention, there is provided a method for generating and supplying hydrogen to a fuel cell, the method comprising:
(a) providing a supply of solution comprising a solvent and an at least one chemical hydride dissolved therein;
(b) supplying the solution to a catalyst in the fuel cell to catalyze the reaction of the solvent and the at least one chemical hydride to generate hydrogen;
(c) removing the solution comprising hydrogen, by-products, and unreacted solution from the fuel cell;
(d) separating the hydrogen from the solution; and
(e) delivering the generated hydrogen to the fuel cell.
The method can further comprise the steps of:
(a) recovering water from consumption of hydrogen in the fuel cell; and
(b) supplying the recovered water to the supply of the solution, to compensate for water consumed during the reaction of the solution to generate hydrogen, and to promote maintenance of concentration levels for products of the reaction at acceptable levels, thereby delaying the onset of any precipitation of products tending to limit the generation of hydrogen.
The method can additionally comprise the step of adjusting the temperature of the solution upstream of the fuel cell. For example, the temperature of the solution can be either raised or lowered upstream of the fuel cell.
The internal hydrogen generation fuel cell according to the present invention can be incorporated into a safe and compact fuel cell system, eliminating the need for bulky storage and/or separate reformer subsystems. Moreover, the chemical hydride solution stream absorbs and removes heat from the fuel cell stack. Accordingly, a separate cooling loop may no longer be required. Furthermore, the hydrogen gas may be humidified by the water vapor from the chemical hydride solution. Therefore, a separate humidification system for the anode may no longer be required. Accordingly, the system is simplified, thereby resulting in improved system efficiency and enhanced power density. Since chemical hydride reactions of the present invention can take place at subzero temperatures, the fuel cell system of the present invention can start at lower temperatures than conventional fuel cells.

Method and apparatus for generating hydrogen inside of a fuel cell


A tibial insert and baseplate system is disclosed for a prosthesis. The tibial baseplate is right or left knee specific while the insert is symmetrical about an anterior-posterior centerline and is thus not right or left knee specific. The baseplate has an outer periphery which is asymmetrical to mate exactly with either the left or right tibia but not with both. The upper surface of the baseplate, which also has an asymmetrical periphery, in addition, defines a symmetrical housing within the periphery for the symmetrical insert.

There is a well known fact that the joints of humans as well as animals deteriorate over time. Sometimes deterioration occurs because of disease due to aging and sometimes due to a trauma. The knee joint is perhaps the one joint that has given people the most trouble over the years because of its essential function to the mobility of humans. Thus, quite naturally, a great deal of research has gone into the development of replacement knees. Today, because of this widespread research, a significant portion of our population is again mobile and relatively free of pain. This great step forward in medical research has not been without its difficulties. Primarily because of the tremendous stresses placed on the knee joint, there continues to be a need for improvement to eliminate the last vestiges of pain and suffering.
Prosthetic surgery involving the excision and removal of deteriorated and diseased bone tissue in knee and hip joints has now become quite common. Typically, artificial members of plastic and/or metal compatible with the human body are substituted for the removed natural bone segments and anchored to the remaining bone structure.
The bearing surfaces of the knee joint are especially vulnerable to stress, arthritic and other disease induced deterioration. Prosthetic correction is necessary when the surfaces become so damaged that other less drastic techniques have little or no prospect of success.
In a healthy knee, the lower leg bone, called the tibia, has at its upper end a pair of concave surfaces. These concave surfaces meet with condyles which are formed in the lower end of the femur, which is the upper leg bone. This meeting is protected by the patella (knee cap). Thus, in a knee replacement operation, the upper end of the tibia is removed as is the lower end of the femur, and these bones are replaced with prostheses, which are designed to operate together.
In the past, there have been two major types of knee prostheses: hinged and non-hinged. In one form, the knee was resected and replaced by a metal hinged-type device with deep penetration into the remaining femoral and tibial bone structure by means of flared and thick stems. The range of movement was limited and patients were seldom able to flex the knee beyond 90.degree. . Moreover, implantation required the removal of a significant amount of the bone with a shortening of the limb if for any reason the prosthesis was later removed.
More recent prostheses using a different approach attempt to structurally resurface both of the articulating surfaces of the knee to provide a non-hinged type prosthesis. Such prostheses seek to remedy the failure of hinged devices, and involve two components which are respectively connected with the femur and tibia and held in engagement by the muscles and ligaments to produce a more lifelike situation.
The non-hinged knee prostheses must contend with the particulars of the human knee joint. The tibia is situated at the front (anterior) and inner (medial) side of the lower leg and, except for the femur, is the longest and largest bone in the human skeleton. It is prismoid in form, expanded above, where it enters into the knee joint. The head of the tibia is large and expanded on each side into two eminences called the tuberosities. The tops of these present two smooth concave surfaces which articulate within the knee with the condyles of the femur. The medial condyle is more prominent anteriorly and broader both in the anterior-posterior (front-rear) and transverse diameters than is the outside (lateral) condyle. Accordingly, the lateral top articular surface of the tibia is longer, deeper and narrower than the medial surface of the tibia so as to articulate with the lateral condyle. The medial surface is broader and more circular, concave from side to side, to articulate with the medial condyle. The anterior surfaces of the tuberosities are continuous with one another, forming a single large surface which is somewhat flattened. Posteriorly the tuberosities are separated from each other by a shallow depression for attachment of ligaments. The inner (medial) tuberosity presents posteriorly a deep transverse groove for the insertion of the posterior cruciate ligament (PCL).
In the past, tibial prostheses (commonly called baseplates because they fit beneath the condyles of the femur) were manufactured with total symmetry for use with both left and right knees which, as was discussed above, are not symmetrical. Although the symmetrical components were interchangeable between the right or left tibia, there were problems with the baseplate overhanging the lateral tibial bone surface or undersized on the medial tibial bone surface. The result was a compromise in the fit of the prosthesis. In response thereto, asymmetric tibial prostheses (baseplates) were developed to more closely approximate the natural tibial anatomy. The problem with such asymmetric tibial prostheses is that they require asymmetric, or knee specific removable tibial baseplate inserts (the concave bearing surface which actually contacts the femoral condyles) necessitating the need for a hospital to maintain an inventory of left and right knee specific inserts.
U.S. Pat. No. 4,963,152 provides a partial solution to the problems associated with symmetrical tibial prostheses. The patent discloses an asymmetrical tibial prosthesis whereby asymmetry is created by having the outer radius which describes the medial condyle slightly greater than the outer radius describing the lateral condyle. However, the baseplate is symmetrical about the medial-lateral centerline, allowing it to be used on either left or right tibia by rotating the baseplate 180.degree. about the centerline. The insert, which is designed to mate with the baseplate, is also symmetrical about the medial-lateral centerline. The disadvantage of such a tibial prosthesis is that it must include an anterior as well as a posterior relief notch for the PCL in order to allow the baseplate to be reversed and thus usable on either the left or right knee. The "extra" notch, along with the symmetrical geometry of the baseplate about the medial-lateral centerline, does not provide the best coverage of the prosthesis upon the head of the tibia.
In order to provide the best coverage, the baseplate should be formed with only one notch for the PCL and thus cannot be symmetrical about either the medial-lateral centerline or the anterior-posterior centerline. However, such a baseplate would require a correspondingly asymmetrical insert under the teachings of the prior art.
Since these inserts may wear out and require replacement prior to the tibial baseplate, it becomes more costly from an administrative standpoint to maintain an inventory of both left and right knee inserts.
What is needed is a low cost symmetrical tibial insert that can be mass-produced so as to lower inventory and replacement costs and which is still usable in conjunction with an asymmetric tibial baseplate.
The object of the present invention is to provide a knee prosthesis having a tibial baseplate specific to the left or right tibia but allowing for the placement of an insert which is symmetrical about its anterior-posterior centerline and thus not left or right knee specific. The knee prosthesis also includes a femoral component having condyles for articulating with the condyle compartments of the symmetrical insert.


A method and apparatus for improving the reliability of resynchronization in a serial frame based protocol communication system which can avoid resynchronization when line loss erroneously causes data to appear as a redundant unique code pattern. The synchronization is only initiated if two such unique code pattern bytes are received within a specified time separation.

Several high speed data communications systems are known which employ encodement of transmitted data in a unique way so that byte boundaries can be conveniently recovered and so that DC balance of the coded data is maintained. One such system is known as the 8B/10B code which is described in the article by Widmer et al., entitled "A DC Balanced Partitioned Black, 8B/10B Transmitter Code," "Journal of Research and Development," Volume 27, 1983, pp. 440-451.
As described in the above article, special encoded characters are provided for several command purposes which characters are distinguishable from other valid coded characters even when byte boundaries are incorrectly aligned. One major purpose of such special characters is for synchronization between the transmitter and receiver. In the 8B/10B System, the special characters are generated by the same coding rules used for data encodement regarding disparity, maximum run length and maximum digital sum variation. A first group of eight of the special characters are called K28.X. These special characters can be recognized as other than data because abcdei=001111 or 110000. Valid data code does not have the case c=d=e=i.
By virtue of the 8B/10B rules set forth in the above article, the code provides three characters K28.1, K28.5 and K28.7 which are defined as containing a "comma." Comma is defined as a unique digital sequence which will occur with uniform alignment relative to byte boundaries. This means, absent transmission error, that the comma sequence cannot occur by misalignment of any valid data or command code in combination with other valid code. The binary 10 bit 0011111XXX has this characteristic. Several codes are defined which contain the comma sequence. The ANSI X3T9.3 Fibre Channel Standard Working Group has selected one such code, K28.5.5, and has established its use as the first byte of all delimiters and primatives. Each delimeter and primitive is defined as a four byte set. In the Fibre Channel Standard, K28.5 is not permitted to be followed by K28.1 or K28.7 in any of the defined command ordered sets, such as Start of Frame (SOF), End of Frame (EOF) or primitives such as the Idle (I) or Receiver Ready (RRDY).
In view of the above rules, prior 8B/10B receiver systems employed the detection by the receiver of a single comma as a sufficient condition to send resynch flag to initiate synchronization or resynchronization of the data byte boundaries in the receiver.
While the K28.5 code is unique and cannot be formed by valid aliased code, if there are transmission errors, such as 1 bit or 2 bit errors, the K28.5 can be randomly created which byte would not necessarily create a detectable disparity error. In existing 8B/10B decoders, this condition can cause a misalignment of data byte boundaries and result in long runs of erroneous data decoding.
Accordingly, it is an object of this invention to provide a method and apparatus providing a type of redundancy check before a synchronization or resynchronization is allowed.

Method and apparatus for synchronizing transmitter and receiver for high speed data communication


A circuit according to embodiments includes: a plurality of bit-string comparators each of which includes a plurality of single-bit comparators each of which includes first and second input terminals, first and second match-determination terminals, and a memory storing data and inverted data in a pair, the first input terminal being connected to a respective search line, the second input terminal being connected to an inverted search line being paired with the respective search line, and a matching line connecting the first and second match-determination terminals of the single-bit comparators; a pre-charge transistor of which source is connected to a supply voltage line; a common matching line connected to a drain of the pre-charge transistor and the matching lines of the bit-string comparators; and an output inverter of which input is connected to the common matching line.

A reconfigurable logic circuit as typified by a field programmable gate array (FPGA) realizes a predetermined logic (circuit configuration) based on data stored in a configuration memory.
As main circuit components of a FPGA, there are a LUT (look-up-table) realizing an arbitrary truth table and a MUX (multiplexer) selectively outputting a predetermined signal from among a plurality of input signals.
The conventional LUT is structured with configuration memories and a selection circuit unit. The LUT outputs data stored in one of the configuration memories selected by the selection circuit according to an input signal.
The conventional MUX is structured with a configuration memory and a selection circuit. The MUX outputs one input signal selected by the selection circuit from among a plurality of input signals according to data stored in the configuration memory.
In this way, because the conventional LUT and MUX are respectively structured by one or more configuration memories and a selection circuit, they have comparatively large circuit sizes. Therefore, the conventional LUT and MUX have had such a problem in that a chip area being large, or a signal delay being long.

Circuit having programmable match determination function, and LUT circuit, MUX circuit and FPGA device with such function and method of data writing


It is an object of the present invention to provide a method for reducing a user's operation procedures in a pop-up menu and for effectively locating the user's desired processing. A computer (1) displays a pop-up menu based on a list of at least one processing item stored in advance at a position designated by data indicative of a display request in a display unit (14) in response to receipt of the data indicative of the display request of the pop-up menu through an input unit (13). While continuing the display of the pop-up menu in response to receipt of data through the input unit (13) indicative of one processing item selected from the list, the computer (1) displays a form for receiving a parameter input corresponding to the processing item, receives input data for the form through the input unit (13), and stores the data as parameters of the processing item.

Conventionally, in application software running on a computer, there are cases in which input of parameters for command instructions for processing, input or changes of properties, or the like are accepted. As a result, pop-up menus are used in many cases as one type of user interface.
For pop-up menus, a screen is displayed in response to, for example, a right-click of a mouse operated by a user, and by selection of a processing item from a displayed list, a corresponding process is executed. At that time, in a case where parameter input is required, a dialog box provided for this purpose is displayed, and input is accepted while execution of processing is triggered by pressing of the "run" button or the like provided in the dialog box.
Here, in application software, the more functions provided, the more processing items are displayed in pop-up menus, so it can also be considered that, for a user, an amount of time to search for a desired processing item increases.
Therefore, a method is proposed for improving a user interface with this kind of possibility of reducing convenience. For example, in Patent Document 1, a method is disclosed in which, by enabling effective display of a shortcut menu (pop-up menu) composed of a plurality of (many) levels, operability of the shortcut menu is increased, and it becomes possible for a user to carry out the user's desired processes more quickly.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2006-59155


Quasi-isotropic chopped prepreg is used to make parts found in aerospace vehicles. Exemplary aerospace parts that are made using quasi-isotropic chopped prepreg include aircraft window frames, wing fairing supports, flange supports, frame gussets, rudder actuator brackets, shear ties, seat pedestals, cargo floor flange supports, storage bin fittings, antenna supports, torque tube pans, handle boxes, side guide fittings, wing box covers and intercostals.

1. Field of the Invention
The present invention relates to composite materials and processes for their use in the aerospace industry. More particularly, the invention is directed to quasi-isotropic chopped prepreg and the use of such composite material for the production of structural parts and other components having complex geometries that are designed for use in aircraft and other aerospace vehicles.
2. Description of Related Art
Lightweight metals, such as aluminum and magnesium alloys, have long been used as standard materials to make a wide variety of parts that are used in aircraft and other aerospace vehicles. Stronger and heavier metals, such as steel and titanium alloys, are also commonly used in place of aluminum to make aerospace components where there is a particular need for structural strength, fatigue resistance and/or galvanic corrosion protection.
Composite materials have become a popular replacement for many aerospace metal parts because composites are much lighter. However, there are a number of complex engineering issues that must be considered when replacing a metal part with a composite material. The performance of the composite part under a number of different stress loads must be carefully analyzed and compared to the metal part being replaced. Typical mechanical properties that are measured include compression strength, compression modulus, tensile strength, tensile modulus, flexure strength, flexure modulus and short beam shear. Standardized tests for measuring these various mechanical properties are described in ASTM D6272, ASTM D3039, ASTM D695 and ASTM D2344.
The flaw sensitivity properties of the composite part must also be carefully analyzed and compared to the metal part that is being replaced. This is especially important with respect to composite parts that include holes for attaching the part to aircraft structures. Such parts include window frames, wing fairing supports, flange supports, frame gussets, rudder actuator brackets, shear ties, seat pedestals, cargo floor flange supports, storage bin fittings, antenna supports, intercostals and other aerospace parts that form bolted or riveted joints in the vehicle structure. The holes form voids in the composite that are considered to be flaws. Exemplary flaw properties that must be analyzed include un-notched compression, open hole compression, bearing (ASTM 5961) and compression-after-impact.
Prepreg is used widely in the manufacture of composite parts. Prepreg is a combination of an uncured resin (matrix) and fiber reinforcement, which is in a form that is ready for molding and curing into the final composite part. By pre-impregnating the fiber reinforcement with resin, the manufacturer can carefully control the amount and location of resin that is impregnated into the fiber network and ensure that the resin is distributed in the network as desired. It is well known that the relative amount of fibers and resin in a composite part and the distribution of resin within the fiber network have a large affect on the structural properties of the part. Prepreg is a preferred material for use in manufacturing aerospace composite parts, since it is important that each composite part meet specific design tolerances that have been established for the part.
The fiber reinforcements that are commonly used in aerospace prepreg are multidirectional woven fabrics or a unidirectional tape that contains fibers extending parallel to each other. The fibers can also be chopped and randomly oriented in the resin to form a non-woven mat. These various fiber reinforcement configurations are impregnated with a carefully controlled amount of uncured resin. The resulting prepreg is placed between protective layers and rolled up for storage or transport to the manufacturing facility.
Prepreg may also be in the form of short segments of chopped unidirectional tape that are randomly oriented to form a non-woven mat of chopped unidirectional tape. This type of pre-preg is referred to as a "quasi-isotropic chopped" prepreg. Quasi-isotropic chopped prepreg is similar to the more traditional non-woven fiber prepreg, except that short lengths of chopped unidirectional tape (chips) are randomly oriented in the mat rather than chopped fibers. Quasi-isotropic chopped prepreg is considered to be "transversely isotropic". The random orientation of the unidirectional chips provides isotropic properties in the plane of the mat. The quasi-isotropic chopped prepreg is therefore a transverse isotropic material. Properties are the same in any direction within the plane of the mat. Outside the plane of the mat (z direction), the properties are, however, different.
Quasi-isotropic chopped prepreg has been available commercially from Hexcel Corporation (Dublin, Calif.) under the tradename HexMC®. Quasi-isotropic chopped prepreg has been used in the past for a variety of purposes including bicycle parts and various other molded parts. However, quasi-isotropic chopped prepreg materials have not been used in the manufacture of aerospace parts. This is especially true for aerospace parts, such as aircraft window frames, that are bolted or riveted to the aerospace structure and a multitude of gussets, brackets and connectors, such as cargo floor flange supports, that form bolted or riveted joints in the vehicle structure.

Aerospace articles made from quasi-isotropic chopped prepreg


An electronic navigational route developer may accept user input regarding the user's boat, such as height, draft and beam, and develop a route from a start point to end point based on cartographic information and the boat information.

Inventive concepts relate to navigational devices and, more particularly, to navigational routers, and methods for performing navigational routing.
Marine vessels may be equipped with radios, radar systems, cameras, global positioning system (GPS) transponders, SONAR systems, and other sensors that provide a variety of information for the operator of the marine vessel, also referred to herein as, simply, a boater. A boater may employ such information, along with other information, such as that obtained from navigational charts, to plan a navigational route, or course, and to navigate along that course to reach a desired destination. Navigational routers, which may be manual or automatic navigational routers, for example, may assist a boater in such endeavors.
Existing navigational routers may be somewhat inflexible, may provide unsatisfactory levels of feedback to operators, or may be incapable of routing under certain circumstances.


This invention relates to a novel cartridge-needle unit having a retractable needle for use with disposable or reusable holders to form safety syringes. The cartridge-needle unit comprises a cartridge comprising a hollow body, a septum at the distal end of the body, means for retaining the septum, and a plunger, axially and reciprocally slidable through the interior of the body; a needle capable of being withdrawn within the cartridge; a hub comprising a sleeve adapted to be snapped on the distal end of the cartridge; means for retaining the needle within the hub during an injection; and means for releasing the needle from the hub after the injection comprising an element capable of passing through the septum. The retractable cartridge-needle unit exhibits improved reliability, reduces the tendency for body fluids and/or medication to remain in an unprotected area upon retraction of the needle and virtually eliminates the possibility that the needle can be released into the patient.

1. Field of the Invention
This invention relates to a cartridge-needle unit having a needle that can retract within the cartridge after use for safe disposal and to a safety syringe comprising such cartridge-needle unit.
2. Description of the Prior Art
Disposable medicament-containing cartridge needle units for use in conjunction with reusable hypodermic syringe holders are well known in the art and in widespread commercial use. Such cartridges conventionally feature a cylindrical body closed at the proximal end with a flexible plunger slidable within the bore of the cartridge and closed at the distal necked-down end with a septum secured to the cartridge by a crimped-on aluminum collar. The necked-down distal end conventionally is fitted with a needle hub/needle/needle sheath assembly. Such cartridge-needle units are available from Sanofi Winthrop Pharmaceuticals under the Carpuject.RTM. trademark.
In use, the cartridge-needle unit must be activated, i.e., the proximal end of the needle cannula must penetrate the sealed septum such that communication is achieved between the fluid and the proximal end of the needle. Some cartridge-needle units are sold in an activated form. Others must be activated by the user. When user activated cartridge-needle units are used in conjunction with conventional reusable syringe holders of the type described, for example, in Hadtke, U.S. Pat. No. 4,585,445 and in EP-A 485,028, this is accomplished when the health care worker advances the cartridge through the holder by rotating a clamping element.
Many holders, including the above-referenced reusable holders, enable the user to avoid handling the cartridge-needle unit when the needle unit is exposed. Nevertheless, health care workers are especially susceptible to accidental and potentially infectious, and indeed, on occasion, possibly fatal, needle strikes due to the careless handling and/or disposing of the cartridge-needle unit after use. The consequences to health care workers of strikes from needles contaminated with various infectious diseases such as hepatitis or AIDS can be particularly severe. The frequency of accidental needle strikes in the United States is surprisingly great, and has been estimated to be approximately one million strikes per year. Moreover, the cost to health care organizations for the testing of health care workers accidentally stricken by used needles is a significant burden on health care costs. This is illustrated in a recent report by Kirkland, Safer Syringes Boost Molder Opportunities, Plastics World, August 1993, pp. 20-24, which states:
"The average cost associated with accidental needle-stick injury in the U.S. reportedly is $3 billion/year. For example, estimates for the average cost associated with testing alone is at least $1,200 per injury. This does not take into account the cost of treatment if disease develops (estimated at $15,700), litigation costs, increased insurance premium costs, replacement of the injured worker, OSHA fines and other costs."
Therefore, it would be desirable to further protect health care workers by providing systems which reduce the possibility of accidental needle strikes.
To this end, it has been suggested to provide syringes having a retractable needle. For example, Haber et al, U.S. Pat. No. 4,909,794, describe a combination retractable needle cannula and cannula lock for a medication carpule, i.e., cartridge. The cannula lock includes a clamp having a pair of jaws which are normally separated from one another so that the needle can be releasably retained therebetween. In the pre-injection state, the clamp is axially spaced from the cartridge, and the jaws of the clamp are rotated towards one another to retain the cannula in an axially extended position for administering an injection. Post-injection, the health care worker continues to apply pressure to the piston stem forcing the empty cartridge to move forward such that the needle embeds in the plunger. Further movement displaces the clamp, whereby the jaws of the clamp rotate away from one another to release the cannula. The cannula may then be retracted within and completely surrounded by the empty cartridge so that the cannula can be safely discarded.
However, the system proposed in U.S. Pat. No. 4,909,794 has been found to be less than satisfactory from a commercial standpoint for a variety of reasons, resulting from both inherent design limitations and reliability concerns.
First, because the needle is released from the jaws of the clamp by the health care worker continuing to apply an axially and distally directed force beyond the point at which all medication is delivered, there is an unacceptably high probability that the health care worker may prematurely release the needle while it is still embedded in the patient. One possible consequence of this may be that the health care worker must then remove a lone sharp needle from the patient.
Second, unlike most current commercial hypodermic syringe designs, this prior art system relies upon an interference fit between the jaws and the hub in order to wedge the needle in place. In fact, Haber et al suggest that the proximal surface of the cannula be textured to enhance the frictional retention of the needle. However, if the frictional force is not great enough, the needle may slip with respect to the jaw both upon injection and removal from the patient. If the fit is too tight and the frictional force is too high, the user may have to deliver an unreasonably high force to release the jaw from the hub. More generally, friction is an unreliable force to use for such a critical function, inasmuch as small variations in dimension, surface finish, cleanliness, or even temperature can alter the desired retention force. While some modifications can be made to improve the reliability of this device and its use of friction, ultimately, there are limitations.
Third, after the jaw is released from the hub, the needle is freed to be withdrawn into the cartridge by the plunger. However, any body fluid and/or medication that may remain on the tip of the needle after removal from the patient can be wiped on the jaw as the needle is retracted. This body fluid then remains in an unprotected area and presents some level of danger to the health care worker.
Haber, U.S. Pat. No. 4,935,014, which is a continuation-in-part of the above-described Haber et al patent, describes another combination retractable needle cannula and cannula lock embodiment in which the jaws of the clamp in the pre-injection state are surrounded by and rotated towards one another by an expandable outer sleeve which retains the cannula in an axially extended position between the jaws for administering an injection. Post-injection, the clamp is displaced outwardly of the sleeve, whereby the jaws are free to release the cannula. It appears that the sleeve enables the syringe to be adapted for use with a cartridge having a head which is narrower in diameter than the cylindrical body. In any event, the syringe described by Haber in U.S. Pat. No. 4,935,014 contains jaws and suffers from the same inherent design limitations and reliability concerns as described above.
It would be desirable to provide a cartridge-needle unit having a retractable needle which (1) reduces the tendency for body fluids and/or medication to remain in an unprotected area upon retraction of the needle into the cartridge, (2) does not rely upon an unpredictable frictional fit between the needle and hub and (3) virtually eliminates the possibility that the needle can be released into the patient.

Cartridge-needle unit having retractable needle