The invention relates to a fuel cell system (1, 2) having at least one or more fuel cells (10, 30), wherein the fuel cell (10, 30) extends between a first cell end (10a, 30a) and a second cell end (10b, 30b) in a tubular shape, and wherein the fuel cell (10, 30) is mechanically received with the first cell end (10a, 30a) on an inflow distributor unit (11, 33), and wherein a fuel gas flows through the fuel cell (10, 30), the gas entering the first cell end (10a, 30a) and exiting one of the cell ends (10a, 10b, 30a, 30b) as exhaust gas. According to the invention, means (12, 16, 18, 32) are provided which suction at least a part of the exhaust gas exiting the fuel cell (10) and feed said gas to the inflow distributor unit (11, 33) for recirculation.

The present invention relates to a fuel cell system having at least one or more fuel cells, wherein the fuel cell extends between a first cell end and a second cell end in tubular form, wherein the fuel cell is mechanically received with the first cell end on an inflow distributor unit, and wherein a fuel gas flows through the fuel cell, entering the first cell end and exiting one of the cell ends as exhaust gas.
Fuel cell systems of the type of interest here concern so-called SOFCs (Solid Oxide Fuel Cells). Fuel cells of this type have a ceramic electrolyte body of tubular form, the tube either being open at both ends or having a closed end side. The tubular basic form can be formed, for example, by electrolyte-supported fuel cells (ESC—Electrolyte-Supported Cells) or by anode-supported fuel cells (ASC—Anode-Supported Cells). The tubular basic form is therefore prescribed either by the electrolyte body or by an anode body. By virtue of the tubular form with two open ends or one closed and one open end, these can therefore be distinguished from planar designs of fuel cells.
The core of such fuel cell systems is formed by cells, in which a fuel gas (e.g. methane, hydrogen, carbon monoxide or a mixture) reacts, with the evolution of current and heat, to form carbon dioxide and water. In this case, natural gas which has been entirely or partially converted beforehand, depending on the system concept, by catalytic pre-reforming to form hydrogen has to be fed to the anode side. In this case, air is fed to the cathode, the cathode usually being applied on the outside in the case of tubular fuel cells, and the fuel gas can flow through the tubular fuel cell and electrochemically interact with the anode applied to the inside of the fuel cell.
Tubular fuel cells are mechanically received on a distributor unit, generally referred to as a manifold. If the fuel cells have an open form, the fuel gas is usually introduced through the first cell end, via which the fuel cell is mechanically received on the distributor unit, and exits the fuel cell via the opposing, second cell end. The fuel gas therefore flows from one end to the other end of the tubular fuel cells, it being possible for a plurality of fuel cells to be received on a distributor unit. If the fuel cells are closed at the second, free cell end, a lance is introduced into the tubular body of the fuel cell, such that the fuel gas, according to the prior art, is guided through the lance to the closed end of the fuel cell, in order to then flow back between the lance and the inside of the electrolyte body past the anode again in the direction toward the distributor unit.
Tubular fuel cells generally have a greater service life since the single-sided clamping and the small sealing length between the fuel cell and the distributor unit avoid thermomechanical stresses. Primarily, seals which are generally formed from solder glass can have a greater stability in the case of operating times of 40 000 to 150 000 hours if they do not have to be arranged in the hot region of the fuel cell system. To increase the service life, it would be expedient, however, to dispense with the use of seals entirely.
In order to obtain uniform feeding of fuel gas into the entire fuel cell and sufficiently effective distribution of the fuel gas in the cell, it is necessary to feed more fuel gas than can be utilized electrochemically via the anode wall for generating current. The ratio of converted fuel gas to fed fuel gas is referred to as the gas utilization level. Excess fuel gas can be burned in an afterburner. It is thereby no longer available for the current generation. Alternatively, excess fuel gas can in some cases be mixed with the fresh fuel gas and fed back to the stack, which is referred to as recirculation. This achieves the advantage that a higher gas flow prevails in the fuel cell system, without it being necessary to burn additional fuel gas. This enables operation with a greater service life combined with a high degree of efficiency. In this case, it is generally the case that between 50% and 90% of the exhaust gas is recirculated.
Fuel cells which are open at the ends give rise to the problem of feeding some of the exhaust gas which contains unburnt fuel gas back to the distributor unit for recirculation. As a result of thermal expansion and further thermal effects, it is often disadvantageous to mechanically clamp the tubular fuel cells both via the first cell end and via the second cell end, for example in order to receive and to dissipate the exhaust gas exiting the second cell end. Consequently, all of the exhaust gas is often burned with a high proportion of fuel gas which has not been utilized by electrochemical reaction.
The object of the invention is therefore that of providing a fuel cell system having improved fuel gas circulation. In particular, it is the object of the invention to provide a fuel cell system having an increased service life. In addition, it is the particular object of the invention to feed unburnt fuel gas for recirculation in an advantageous manner, where at the same time mechanical and thermal loading of the fuel cell and of appropriate sealing elements is minimized.

Fuel cell system having improved fuel gas circulation


Methods, systems and computer program products are disclosed for monitoring user behavior for a server application in a computer network. The methods, systems, and computer program products can monitor communication data between a server application and a client. The methods, systems, and computer program products can also include applying one or more detectors to the communication data to identify a variety of predetermined activity. Further, the methods, systems, and computer program products can include generating a threat score associated with the predetermined activity by comparing the identified predetermined activity with a security threshold criteria.

The ease, accessibility, and convenience of the Internet have rapidly changed the way people use computers and access information. The World Wide Web (WWW), often referred to as "the web", is one of the most popular means for retrieving information on the Internet. The web gives users or clients access to an almost infinite number of resources such as interlinked hypertext documents or server documents retrieved via a hypertext transfer protocol (HTTP) from servers located around on the world. The web operates in a basic client-server format, wherein servers are dedicated computers or individual computer applications that execute resources in a certain matter, such as storing and transmitting web documents or binary objects, to client computers or web-enabled devices on the network. For example, a user or client can interact with a server, or web server, through a web browser on a web-enabled device in order to view retrieved information or to request an application on the web server to operate in a desired manner.
Documents on the web, referred to as web pages, are typically written in a hypertext markup language (HTML) or similar mark-up language, and identified by uniform resource locators (URLs) or uniform resource identifiers (URIs) that specify a particular computer and pathname by which a file or resource can be accessed. Codes, often referred to as tags, embedded in an HTML document associate particular words and images in the document with URLs so that a user or client can access another file or page by pressing a key or clicking a mouse button. These files generally comprise text, images, videos, and audio, as well as applets or other embedded software programs, written in for example, Java or ActiveX, that execute when the user or client activates them by clicking on a hyperlink. A user or client viewing a web page can also interact with components that, for example, forward requested information supplied by the client to a server through the use of forms, download files via file transfer protocol (FTP), facilitate user or client participation in chat rooms, conduct secure business transactions, and send messages to other users or clients via e-mail by using links on the web page.
A web server and surrounding network environment can be vulnerable to attack from malicious or irresponsible individuals via one or more web-enabled devices communicating with the web server. This is referred to as "web hacking" and generally involves taking advantage of mistakes or vulnerabilities in web design through a web application on the web server. Web hacking is different from traditional system or application hacking because an attack generally takes place via application layer protocols. Generally, the easier it is for clients to talk or interact directly to the server applications through a web page or any other suitable type of computer-readable data, the easier it is for someone to hack into those applications. Typical attacks include defacing a page by deleting graphics and replacing them with doctored, sometimes lurid, graphics; altering or stealing password files; deleting data files; pirating copyrighted works; tampering with credit and debit card numbers, or other customer information; publicizing private business information; accessing confidential or unauthorized information; searching through internal databases; data mining; using the web application as a vehicle to attack other users or clients; and denial of service attack. Thus, web hacking causes inconvenience and perhaps irreversible damage to users, clients, customers, businesses, and operators of the web server. Generally, conventional computer security methods fail to properly address or completely ignore web hacking concerns.
The International Standards Organization (ISO) developed a set of protocol standards designed to enable computers to connect with one another and to exchange information with as little error as possible. The protocols generally accepted for standardizing overall computer communications are designated in a seven-layer set of hardware and software guidelines known as the open systems interconnection (OSI) model. This protocol model forms a valuable reference and defines much of the language used in data communications. The application layer is the highest layer of standards in the OSI model. The OSI model also includes the data link layer, the physical layer, the session layer, and the transport layer.
Conventional security methods are typically implemented between either the data link layer and physical layer by using a firewall or the session and transport layers by using a secure socket layer (SSL) or public key infrastructure (PKI). A firewall is a type of security implementation intended to protect a trusted environment, network, or web server against external threats at the data link layer originating from another network, such as the Internet. A firewall prevents computers behind the firewall from communicating directly with computers external to the protected environment, network, or web server. Instead, all communications are routed through a proxy server outside of a trusted environment, network, or web server. The proxy server decides whether it is safe to let a particular message type or file type pass through, based on a set of filters, to the trusted environment, network, or web or application server.
SSL is an open standard developed by Netscape Communications Corporation of Mountain View, Calif., for establishing a secure and encrypted communications channel to prevent the interception of critical information, such as credit card information. The primary purpose of using SSL is to enable secure and encrypted electronic transactions on public networks, such as the web. A public key infrastructure or trust hierarchy is a system of digital certificates, certificate authorities, and other registration authorities that verify and authenticate each party involved in a communication session. PKIs are currently evolving and there is no single PKI nor even a single agreed-upon standard for setting up a PKI. One drawback of the above noted conventional technologies is that they do not perform an inspection of the application layer protocol, i.e., they do not scrutinize the application content of an incoming request. Therefore, these technologies cannot prevent web hacking attacks directed through the application content of an operation request.
Web hackers can easily attack computer systems by exploiting flaws and vulnerabilities in web design. For example, default scripts may allow files to be uploaded onto a web server; a web server's treatment of environmental variables may be exploited; and the existences of 'backdoors' or flaws in third party products allow unauthorized access. These techniques can be potent attacks and are generally difficult to defend against through conventional means. Each month new software vulnerabilities are discovered, but many system operators typically leave these holes unpatched and their systems open to preventable attacks. Major corporations and government agencies utilizing well configured firewalls, PKI, and SSL implementations have been infiltrated by hackers using known application layer intrusions. These intrusions typically involve illegal and harmful requests that are sent to an application forcing it to execute out of its intended or authorized scope of operation. This may exploit the application to damage itself, files, buffers, other applications, performance, or confidentiality of information.
Two conventional approaches attempt to address some of these problems. One technique involves tracking a server operating system to identify suspicious events such as deleting a file or formatting a disk. However, this type of reactionary technique typically activates only after damage has commenced or been completed. A second technique involves the installation of a network filter in front of an application and updating the filter database with known patterns that can affect the application. However, this technique is limited in that it is unable to identify patterns, which are not yet "known" by the filter database. In other words, the capability of this technique is directly related to the comprehensiveness of the filter database that it draws the patterns from. To increase capability, the filter database requires continual updating. Further, these techniques will not protect against manipulations of environmental variables or the application's implemented business process. These techniques also fail to account for and protect against vulnerabilities in the application itself such as input validation errors, authentication errors, authorization errors, and lack of usage policy enforcement.
In addition, conventional security solutions typically fail to address the increased hacking opportunities caused by the proliferation of electronic commerce (e-commerce), mobile, interactive television (iTV) applications, and web services applications. These applications generally require the combination of numerous components operating on different platforms all working together using different technologies. For example, a single application can comprise a plurality of components, such as, a web server application; transaction server application; database; and Java, ActiveX, and Flash applets all working together. Generally, conventional security solutions are unable to meet the unique security needs of each component in a multiple component system.
Based on the foregoing, it is apparent that it can be difficult to anticipate, recognize, or prevent all types of web or server hacking. Therefore, it is desirable to provide a system for monitoring communication between an application server and client application to alert operators to suspect activity. It is also desirable to provide a system for associating suspect activity with a particular web-enabled device, client, user name, or user session.

Methods, systems and computer program products for monitoring user behavior for a server application


Fuel injectors and methods of fuel injection allowing direct control of the flow of fuel at an intensified pressure to the needle. A valve, typically a spool valve, is placed in the fuel passage between the intensifier actuation piston and the needle, and controlled by a control valve which may be independent of the control valve controlling the coupling of actuation fluid and a vent to the intensifier actuation piston. This allows achievement of intensification before initiating injection, and control of multiple injections in a single injection event while maintaining fuel intensification throughout the duration of the injection event. Various embodiments are disclosed, including embodiments having multiple intensifiers, having control of pressure over the needle, having two stage control valve systems for control of intensifier actuation fluid, and combining control of one of the intensifiers and the valve controlling flow of intensified fuel to the needle for injection.

1. Field of the Invention
The present invention relates to the field of fuel injectors, and more particularly to intensifier type fuel injectors.
2. Prior Art
Intensifier type fuel injectors are well known in the prior art. As an example, see U.S. Pat. No. 5,460,329. That patent discloses an electromagnetically actuated spool valve for controlling the coupling of an area over an intensifier piston to an actuating fluid under pressure or to a vent, the intensifier piston driving a smaller piston to intensify the pressure of fuel for injection purposes. While various types of valves are known for use with such injectors, the valves generally control the flow of actuation fluid to and from the area over intensifier piston.
While control valves of the foregoing type can be made relatively small and fast-acting, control of actuation fluid in this manner for direct fuel injection has certain limitations. In particular, a diesel fuel injector may intensify fuel pressure to a pressure on the order of 20,000 psi or higher, at which pressures the fuel will undergo substantial compression. This, in turn, means that there must be substantial actuation fluid flow into the chamber over the larger piston of the intensifier. In that regard, while, by way of an example, in an intensifier having an area ratio of 9:1, the pressure of the actuating fluid over the larger piston will only be 1/9 of the intensified pressure, the flow of actuation fluid required to achieve the compression and intensification of the fuel will be nine times that required because of the compression of the intensified fuel, thereby resulting in at least as much volumetric compression in the actuation fluid over the intensifier piston as in the intensified fuel. Consequently, intensification on actuation of the control valve(s) requires significant actuation fluid flow, and is therefore less than immediate. Also, this flow requirement sets the minimum size for the electrically operated control valves, and further requires de-intensification between injection events, making multiple injections during a single injection event difficult and energy consuming.


This invention relates to system architectures, specifically failure-tolerant and self-reconfiguring embedded system architectures. The invention provides both a method and architecture for redundancy. There can be redundancy in both software and hardware for multiple levels of redundancy. The invention provides a self-reconfiguring architecture for activating redundant modules whenever other modules fail. The architecture comprises: a communication backbone connected to two or more processors and software modules running on each of the processors. Each software module runs on one processor and resides on one or more of the other processors to be available as a backup module in the event of failure. Each module and backup module reports its status over the communication backbone. If a primary module does not report, its backup module takes over its function. If the primary module becomes available again, the backup module returns to its backup status.

This invention relates to the field of system architectures, specifically failure-tolerant and self-reconfiguring embedded system architectures.
In considering a conceptual design for an Unmanned Ground Combat Vehicle (UGCV) prototype, one important design criterion is survivability. This is interpreted in at least one context to mean an ability of the vehicle system to sustain damage to, or failure of, portions of the onboard vehicle hardware and software control systems, while still maintaining some level of operational capability, even at a degraded level. As a result of this design criterion, a system concept has been developed that provides a capability to detect damage to or failure of portions of the system, and through inherent redundancy and self-monitoring, the system can reconfigure itself to recover functionality initially lost as a result of the damage. The system described herein is primarily a software implementation, although it relies on certain hardware configuration assumptions without which it will not function as described.
This system could be used in any distributed computing system that requires multiple levels of redundancy and is exposed to hazardous conditions or vulnerable to severe physical damage. Examples include battlefield systems, mining equipment, spacecraft, heavy industrial equipment, explosive atmospheres, tornado/hurricane monitoring equipment, and similar applications for military, government, or industrial users.

Practical, redundant, failure-tolerant, self-reconfiguring embedded system architecture


A method of providing media content access is disclosed that includes providing a list of available media content to a display device and receiving a selection related to the list of available media content. The method further includes sending data related to the selection to a content source and to an access rule source and receiving media content from the content source based on the selection and an access rule related to the media content from the access rule source. The method also includes applying the access rule to the selected media content, where the access rule defines a restriction to limit access to the media content.

Viewing media content, such as television programs, is a part of daily life for many people. Advances in technology allow service providers to offer a wide range of media content, including television programming, video on demand services, network digital video recording services, and other services. Such advances in technology may also allow users to share media content with other users via their respective set-top box devices. Hence, there is a need for systems and methods to provide media content.

System and method of providing media content


Methods of obtaining mutant nucleic acid sequences that demonstrate elevated oxaloacetate α-decarboxylase activity are provided. Compositions, such as genetically modified microorganisms that comprise such mutant nucleic acid sequences, are described, as are methods to obtain the same.

3-hydroxypropionate ("3-HP", CAS No. 503-66-2) has been identified as a highly attractive potential chemical feedstock for the production of many large market commodity chemicals that are currently derived from petroleum derivatives. For example, commodity products that can be readily produced using 3-HP include acrylic acid, 1,3-propanediol, methyl-acrylate, and acrylamide, as shown in FIG. 1. The sum value of these commodity chemicals is currently estimated to exceed several billions of dollars annually in the US. However, the current petrochemical manufacturing techniques for these commodities adverse impact the environment via the pollutants generated and the energy used in their production. Manufacture of these same commodities via the clean, cost-effective, production of 3-HP from biomass will simultaneously reduce toxic waste and substitute renewable feed stocks for non-renewable resources. In addition to the environmental benefits associated with bio-based production of 3-HP, if the production cost of the derived commodities is substantially reduced relative to petroleum-based production, this would make a biorefining industry not only environmentally beneficial but also a very attractive investment.
Previous attempts to produce 3-HP via biological pathways provide product titers which have been low and these processes have required the use of expensive, rich media. Both of these factors limit commercial feasibility and profitability. The use of rich media was necessary due to the toxicity of 3-HP when fermented with the more economical minimal media. For example, in wild type E. coli, metabolic activity is significantly inhibited at levels of 3-HP that are 5-10 times lower than the approximate 100 g/L titer needed for economic feasibility using the more economical minimal media. In fact, toxic effects have also been observed in rich media at product titers which are approximately two times lower than desired titers for commercial feasibility (Refer to FIG. 2). Further, the fermentative pathways reported by other investigators have not addressed and resolved the toxicity mechanisms of 3-HP to the host organisms. Further to issues related to commodity chemical production, which largely relies on petroleum-based starting materials, there is an increasing need to reduce the domestic usage of petroleum and natural gas. The numerous motivating factors for this increasing need include, but are not limited to: pollutant reduction (such as greenhouse gases), environmental protection, and reducing the dependence on foreign oil. These issues not only impact fuel markets, but also the markets of numerous other products that are currently derived from oil. Biorefining promises the development of efficient biological processes allowing for the conversion of renewable sources of carbon and energy into large volume commodity chemicals.
A biosynthetic route to 3-HP as a platform chemical would be of benefit to the public, not only in terms of reduced dependence on petroleum, but also by a reduction in the amount of pollutants that are generated by current non-biosynthetic processes. Because 3-HP is not currently used as a building block for the aforementioned commodity chemicals, technical hurdles must be surmounted to achieve low cost biological routes to 3-HP. These hurdles include the development of a new organism that not only has a metabolic pathway enabling the production of 3-HP, but is also tolerant to the toxic effects of 3-HP thus enabling the sustained production of 3-HP at economically desired levels.
There are numerous motivating factors to reduce the domestic usage of petroleum. These factors include, but are not limited to: 1) the negative environmental impacts of petroleum refining such as production of greenhouse gases and the emission of a wide variety of pollutants; 2) the national security issues that are associated with the current dependence on foreign oil such as price instability and future availability; and 3) the long term economic concerns with the ever-increasing price of crude oil. These issues not only impact fuel markets, but also the multi-billion dollar commodity petro-chemical market
One potential method to alleviate these issues is the implementation of bioprocessing for the conversion of renewable feed stocks (e.g. agricultural wastes) to large volume commodity chemicals. It has been estimated that such bioprocesses already account for 5% of the 1.2 trillion dollar US chemical market. Furthermore, some experts are projecting that up to 50% of the total US chemical market will ultimately be generated through biological means.
While the attractiveness of such bioprocesses has been recognized for some time, recent advances in biological engineering, including several bio-refining success stories, have accelerated interest in the large scale production of chemicals through biological routes. However, many challenges still remain for the economical bio-production of commodity chemicals. These challenges include the need to convert biomass into usable feed stocks, the engineering of microbes to produce relevant chemicals at high titers and productivities, the improvement of the microbes' tolerance to the desired product, and the need to minimize the generation of byproducts that might affect downstream processes. Finally, the product must be economically competitive in the marketplace.
The contributions of bioprocessing are expected to grow in the future as existing biological methods become more efficient and as new bioprocesses are developed. A recent analysis by the U.S. Department of Energy identified a list of the Top Value Added Chemicals from Biomass that are good candidates for biosynthetic production. Eight of the top value added chemicals were organic acids, including 3-hydroxypropionic acid (3-HP). As depicted in FIG. 1, 3-HP is considered to be a platform chemical, capable of yielding valuable derivative commodity chemicals including acrylic acid and acrylic acid polymers, acrylate esters, acrylate polymers (plastics), acrylamide, and 1,3-propanediol. Presently, these high value chemicals are produced from petroleum.
One method to efficiently generate 3-HP by a bioprocess approach would be the microbial biosynthesis of renewable biomass sugars to 3-HP. According to the DOE Report (Werpy, T.; Petersen, G. Volume 1: Results of Screening for Potential Candidates from Sugars and Synthetic Gas. Oak Ridge, Tenn., U.S. Department of Energy; 2004. Top Value Added Chemicals from Biomass), a number of factors will need to be addressed, including: identifying the appropriate biosynthetic pathway, improving the reactions to reduce other acid co-products, increasing microbial yields and productivities, reducing the unwanted salts, and scale-up and integration of the system. Additionally, as noted above, it is critical to engineer the microbial organism to be tolerant to the potential toxicity of the desired product at commercially significant concentrations.
The production of acrylic acid from 3-HP is of particular interest because of the high market value of acrylic acid and its numerous derivatives. In 2005, the estimated annual production capacity for acrylic acid was approximately 4.2 million metric tons, which places it among the top 25 organic chemical products. Also, this figure is increasing annually. The demand for acrylic acid may exceed $2 billion by 2010. The primary application of acrylic acid is the synthesis of acrylic esters, such as methyl, butyl or ethyl acrylate. When polymerized, these acrylates are ingredients in numerous consumer products, such as paints, coatings, plastics, adhesives, dispersives and binders for paper, textiles and leather. Acrylates account for 55% of the world demand for acrylic acid products, with butyl acrylate and ethyl acrylate having the highest production volumes. The other key use of the acrylic acid is through polymerization to polyacrylic acid, which is used in hygiene products, detergents, and waste water treatment chemicals. Acrylic acid polymers can also be converted into super absorbent materials (which account for 32% of worldwide acrylic acid demand) or developed into replacement materials for phosphates in detergents. Both of these are fast growing applications for acrylic acid.
Today, acrylic acid is made in a two step catalytic oxidation of propylene (a petroleum product) to acrolein, and acrolein to acrylic acid, using a molybdenum/vanadium based catalyst, with optimized yields of approximately 90%. It should be noted that several commercial manufacturers of acrylic acid are exploring the use of propane instead of propylene. The use of propane is projected to be more environmentally friendly by reducing energy consumption during production. However, propane is petroleum based, and while its use is a step in the right direction from an energy consumption standpoint, it does not offer the benefits afforded by the bioprocessing route.
In addition to acrylic acid, acrylates, and acrylic acid polymers, another emerging high value derivative of 3-HP is 1,3-propanediol (1,3-PD). 1,3-PD has recently been used in carpet fiber production for carpets. Further applications of 1,3-PD are expected to include cosmetics, liquid detergents, and anti-freeze. The market for 1,3-PD is expected to grow rapidly as it becomes more routinely used in commercial products.
Pursuing a cleaner, renewable carbon source route to commodity chemicals through 3-HP will require downstream optimization of the chemical reactions, depending on the desired end product. 3-HP production through bioprocesses directly, or through reaction routes to the high-value chemical derivatives of 3-HP will provide for large scale manufacture of acrylic acid, as well reduction of environmental pollution, the reduction in dependence on foreign oil, and the improvement in the domestic usage of clean methods of manufacturing. Furthermore, the products produced will be of the same quality but at a competitive cost and purity compared to the current petroleum based product.
Thus, notwithstanding various advances in the art, there remains a need for methods that identify and/or provide, and compositions directed to recombinant microorganisms that have improved 3-HP production capabilities, so that increased 3-HP titers are achieved.

Compositions and methods for 3-hydroxypropionate bio-production from biomass


Integrated speaker enclosures for electronic devices. A device chassis portion with an inner face and an outer face can be connected with a speaker enclosure portion with an inner face, an outer face, and edges. The edges match the inner face of the device chassis portion to provide an audio enclosure when the speaker enclosure portion is aligned with and in contact with the device chassis portion.

The design of acoustics and speakers on electronic systems (e.g., smart phones, ULTRABOOKS™, tablets and all-in-ones) are often designed as 'drop-in' solutions that do not fully utilize available internal volume or achieve best/premium audio output. This leads to a compromised audio experience that in inconsistent with the trend for high quality visual experience. Thus, current audio solutions do not provide an optimal user experience. ULTRABOOK™ is a trademark of Intel Corporation in the United States and/or other countries.


A wind turbine noise suppression system can include a sound absorbing batting and a fabric sheet within a column of the wind turbine. The sheet can hang within the column whereas the batting can be placed in at least a bottom and top region. A vibration isolation pad at the top of the column can mitigate a megaphone effect. The pad can be combined with an isolation washer. The pad can be less than a half inch thick, whereas the isolation washer can be less than a quarter inch thick. A sound curtain can be installed at a base of the column to suppress bell resonance. The system can, for example, reduce wind turbine noise up to ninety percent.

There is an increasing demand for land-based small, medium, and large wind turbine sites for single installation and wind farms. This demand has generally tracked the increase in demand for renewable energy sources. However, wind turbine adoption, particularly in small-scale residential settings, has been hindered by problems associated with noise production.
Wind turbines generate noise from multiple mechanical and aerodynamic sources. Although technology advances have led to quieter turbines, noise from wind turbines remains a public concern. The problems associated with wind turbine noise have been one of the more studied environmental impact areas in wind energy engineering. Noise levels can be measured, but the public's perception of the noise impact of wind turbines is in part a subjective determination. Noise is defined as any unwanted sound. Some factors for noise production can be mitigated by existing technology. Such factors include level of intensity of the noise source(s), frequency of the noise source(s), and frequency distribution and patterns of the noise source(s). Other noise factors cannot be easily mitigated. These can include background noise levels, the terrain between the emitter and receptor, and the nature of the noise receptor.
The effects of noise on people can be classified into three general categories (National Wind Coordinating Committee, 1998: subjective effects including annoyance, nuisance, dissatisfaction; interference with activities such as speech, sleep, and learning; and physiological effects such as anxiety, tinnitus, or hearing loss. Whether a noise is objectionable or not is a function of and varies with the type of noise: tonal, broadband, low frequency, or impulsive. The objectionable nature of the noise is also based on the circumstances and sensitivity of the person (or receptor) who hears it. Because of the wide variation in the levels of individual tolerance for noise, there is no completely satisfactory way to measure the subjective effects of noise or of the corresponding reactions of annoyance and dissatisfaction.
Wind turbines are often sited in rural or remote areas that have a corresponding ambient noise character. Furthermore, while noise may be a concern to the public living near wind turbines, much of the noise emitted from the turbines is masked by ambient or the background noise of the wind itself. At the present time, the noise produced by wind turbines has diminished as the technology has improved. As blade airfoils have become more efficient, more of the wind energy is converted into rotational energy, and less into acoustic noise. Vibration damping and improved mechanical design have also significantly reduced noise from mechanical sources. Despite these advancements, wind industry and acoustic engineering studies have found that wind turbines typically produce sound levels of 95 dBA to 107 dBA measured 1 ft from the turbine source.
Given that noise is a primary obstacle for gaining broad public acceptance, the accurate noise assessment of wind turbines is a necessity. Accurate predictions require not only the knowledge of the noise sources and sound levels from each source levels, but a realistic, targeted approach to the suppression, mitigation, and dampening of these multi-modal noise sources. Given the spectrum of frequencies that contribute to the overall noise of wind turbine installations, multiple noise suppression, mitigation and dampening material substrates are required to decrease the sound levels for near and far field noise perceived by ground level observers.
The classical approach for wind turbine system noise predictions assumes an overall source power level for a wind turbine and uses a propagation relationship based on hemispherical spreading. The rule of thumb for wind turbine noise planning assumes that the sound level for wind turbine noise will decrease by 6 dBA each time the distance from the turbine doubles. Even though this approach neglects many physical processes, it has been the standard for some years. Current wind turbine certification standards include a calculate sound level based on the sound pressure level (dBA) not exceeded by the wind turbine 95% of the time at a distance of 60 meters from the rotor with an average wind speed of 5 m/s (11.2 mph). Given the typical wind turbine sound level at 1 ft from the turbine source, the sound meter at 60 meters is calculated to be 95 dBA to 107 dBA which is consistent with field observations.
Design changes intended to mitigate the impact of wind turbine installations on wildlife and visual aesthetics have yielded the increasing adoption of monopole towers by industry and government regulators. The introduction of monopole tower has inadvertently increased vibrational noise and resonant amplification of noise from the turbine.
Noise sources of monopole wind turbine systems include:                Turbine Mechanical Vibration        Turbine Electrical Vibration        Tower Reed Effect        Tower/Wind Turbulence        Blade/Tower Turbulence        Blade/Rotor Turbulence
These noise sources share overlapping acoustical effects that propagate and amplify turbine and tower noise, as shown in Table 1 below.
TABLE 1Multi-ModalNoise SourcesTowerand Multi-Tower OpenTowerStructuralTowerTowerModal ResonantAir ColumnMegaphoneSoundConicalBellCableAmplificationResonanceEffectPropagationResonanceResonanceResonanceTurbineXXXXXXMechanicalVibrationTurbineXXXXXXElectricalVibrationTower ReedXXXXXEffectTower/WindXXXXTurbulenceBlade/TowerXXXXTurbulenceBlade/RotorXXXXTurbulence
Wind turbines have multiple mechanical and structural sources of noise and vibration. Turbine mechanical noise contributes primarily low and medium frequency noise. While this noise is audible at ground level by air transmission, the lower frequencies are particularly well amplified by the column resonance of the monopole tower. Turbine electrical noise contributes primarily very low and low frequency noise This is transmitted primarily to ground level by material transmission through the turbine body and tower.
Wind passing across an opening at the top of the tower or along the tower wall introduces resonant (reed-effect) noise to the interior of the monopole. The frequency of this resonant noise is defined by the diameter, height and shape of the interior of the monopole as well as the size and shape of the opening across which the wind blows. This resonant noise transmitted to ground level by the tower.
Wind turbulence around the tower vibrates the tower wall, introducing resonant noise to the wall of the monopole. This vibrational noise is typically infrasonic or very low frequency and transmitted to ground level by the tower.
Blade rotation sets up structural vibration in the tower wall as each blade passes between the oncoming wind and the tower. The wind striking the tower wall between the blades produces a very low or low frequency vibration that is transmitted into the tower cavity by structural propagation and undergoes resonant amplification.
Blade shape and size result in the medium and high frequency noise commonly referred to as blade whoosh and blade whistle. This noise is primarily transmitted to ground level through the air, but some blade noise is transmitted into the turbine body and tower by solid material transmission.
The problem of resonant and vibrational noise with monopole towers is complicated by the conical shape of the monopole interior. The tapering design of most wind turbine monopoles provides structural stability and weight savings, but the conical shape also provides for column resonance across a wide and continuous spectrum of sound frequencies from infrasound to high frequency based on the internal diameter of the monopole and the length of the interior column space. Further, the hollow cone provides for bell resonance, transmission and amplification of vibrations introduced at the top of the monopole by the turbine.
Systems for mitigating sound resonance for wind turbines are needed, particularly for small-scale wind turbines.

Multi-substrate noise mitigation system for monopole towers of wind turbine systems


A retractable drum fan in which two housing sections are telescoped to form a housing, and an impeller is disposed in the housing for forcing air through the housing. The housing sections are movable between a retracted position and an extended position.

This invention relates to a drum fan for moving relative large quantities of air in domestic and commercial applications.
Drum fans are well known and include a blade, or impeller, that rotates in a cylindrical housing having an air inlet at one end and an outlet at the other. These designs lend themselves to movement of relative large quantities of air such as in commercial applications.
Drum fans of this type are very popular, and therefore are very cost competitive. However, due to their large size, shipping costs add a considerable amount to the total costs of the drum fan to the manufacturer and distributor, and therefore to the customer.
Therefore what is needed is a drum fan that can be shipped at a relative low cost.


A circuit for generating a reference voltage that varies as a function of temperature, in particular for regulating the voltage at which a battery is charged by an alternator, wherein the circuit comprises: a source of a voltage that is fixed regardless of temperature; two bipolar transistors whose bases are interconnected and whose base-emitter junctions have different temperature behaviors, with constant currents flowing through each of them; a first resistor connected between the emitters of the two transistors, with the voltage across the terminals thereof being representative of the temperature to which the two transistors are exposed; and a second resistor connected between the fixed voltage source and an output for the reference voltage, and through which a current may flow, at least over a predetermined range of temperatures, which current is equal to the additional current induced by an increase in the voltage across the terminals of said first resistor relative to a voltage which corresponds to a critical temperature.

It is known that the charging voltage of a vehicle battery can be regulated by controlling the excitation current of the alternator as a function of the result of a comparison between the voltage actually output by the alternator and a given reference voltage.
The reference voltage may be constant, but it turns out to be desirable under certain conditions to vary said voltage as a function of temperature.
In a conventional type of circuit for obtaining a reference voltage that varies as a linear and decreasing function of temperature, the slope and the intercept of the straight line representing the value of the reference voltage as a function of temperature require at least three specific resistance values in the circuit to be determined by calculation or by experiment.
It will thus be understood that such a circuit is poorly adapted to being integrated in a silicon chip, particularly if it is desirable for the circuit to be capable of being parameterized for different characteristic curves of reference voltage as a function of temperature. If N represents the number of possible curves, it then becomes necessary to provide 3xN resistances and associated with fuses that can be actuated externally. The size and the cost of the integrated circuit are thus increased undesirably.
The present invention seeks mainly to mitigate this drawback of the prior art and to provide a circuit for generating a variable reference voltage in which one characteristic curve can be selected from a plurality thereof in a manner which is extremely simple and cheap.
Another object of the invention is to reduce the number of resistances and fuses that are required for obtaining a given number of possible slopes.

Circuit for generating a reference voltage that varies as a function of temperature, in particular for regulating the voltage at which a battery is charged by an alternator


Exhaust systems for a vehicle are provided. In one example, an exhaust system includes a muffler, a first exhaust outlet pipe fluidly coupled to a first outlet of the muffler, a second exhaust outlet pipe fluidly coupled to a second outlet of the muffler, a bypass duct fluidly coupled to a third outlet of the muffler, and a combined X-Y shaped intersection at which the first exhaust outlet pipe, the second exhaust outlet pipe, and the bypass duct are fluidly coupled to each other.

Exhaust systems for vehicles typically include a muffler to attenuate exhaust noise. After traveling through the muffler, the exhaust gas may flow to a tailpipe via a main exhaust outlet pipe. During some modes of operation, it may be desirable to an operator of the vehicle to modulate the exhaust noise, and thus some exhaust systems include an active exhaust valve that, when closed, causes exhaust gas exiting the muffler to flow through a bypass duct rather than the main exhaust outlet pipe. The bypass duct may have a smaller cross-sectional area than the main exhaust outlet pipe, and thus may reduce exhaust noise relative to the exhaust noise generated when the exhaust gas flows primarily through the main exhaust pipe.
Certain vehicles, such as vehicles designed for high power operation (e.g., towing) may include a relatively high number of cylinders (e.g., 8, 12, etc.) and thus the exhaust systems of such vehicles may include two main exhaust pipes to accommodate the large volume of exhaust gas generated by the engine. In these exhaust systems, the outlet side of the muffler may be fluidly coupled to the two main exhaust pipes (each including an active exhaust valve) and two bypass ducts, and the positions of the active exhaust valves may be adjusted to provide desired exhaust noise characteristics.
However, the inventors herein have recognized potential issues with such exhaust systems. As one example, the four outlets of the muffler leading to four exhaust pipes (e.g., the two main exhaust pipes and the two bypass ducts) may result in a heavy exhaust system that lowers fuel economy and is costly to manufacture.
In one example, the issues described above may be addressed by an exhaust system including a muffler, a first exhaust outlet pipe fluidly coupled to a first outlet of the muffler, a second exhaust outlet pipe fluidly coupled to a second outlet of the muffler, a bypass duct fluidly coupled to a third outlet of the muffler, and a combined X-Y shaped intersection at which the first exhaust outlet pipe, the second exhaust outlet pipe, and the bypass duct are fluidly coupled to each other.
As one example, each of the first exhaust outlet pipe and the second exhaust outlet pipe may include a respective active exhaust valve upstream of the X-Y shaped intersection that may be adjusted to allow or block exhaust gas flow through the corresponding exhaust outlet pipe, in order to adjust the proportion of the exhaust gas that flows through the bypass duct and thereby produce desired exhaust sound. The exhaust system includes the single bypass duct that couples to both the first exhaust outlet pipe and the second exhaust outlet pipe at the X-Y shaped intersection. The X-Y shaped intersection includes an X-pipe/intersection that is configured to allow exhaust gas mixing between exhaust gas flowing through the first exhaust outlet pipe and exhaust gas flowing through the second exhaust outlet pipe, which may dampen exhaust gas pulsations, increase engine power, and/or promote desired exhaust sound characteristics. The bypass duct may couple to the X-pipe to form a Y-shaped portion of the X-Y shaped intersection. By including only a single bypass duct (e.g., rather than two separate bypass ducts) and joining the single bypass duct to the exhaust outlet pipes at the X-Y shaped intersection, exhaust system component weight may be lowered and manufacturing costs may be decreased.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.


An apparatus for producing an electrical impulse comprising a tube made of superconducting material; a source of magnetic flux is mounted about one end of the tube; a means for intercepting the flux is mounted along the tube; and a means for changing the temperature of the superconductor is mounted about the tube. As the tube is progressively made superconducting, the magnetic field is trapped within the tube and in so doing creates an electrical impulse in the means for intercepting. A reversal of the superconducting state produces a second pulse.

The present invention relates to superconducting devices, and, in particular, relates to superconducting devices for producing electrical energy.
U.S. Pat. Nos. 5,011,821; 4,999,322; 4,975,699 and 5,026,681 are incorporated by reference.
It is well known that an electromagnetic force or voltage is induced in a conducting loop or coil when there is relative motion between the conducting loop and a magnetic field. Thus, the production of electric power by electromagnetic means requires that a conductor(s) be in a changing magnetic field.
As regards to superconducting materials, the Meissner effect is the expulsion of magnetic flux from the interior of a piece of superconducting material as the material undergoes the transition to the superconducting phase. Under controlled conditions, the Meissner effect is reversible in the presence of a magnetic field. In the presence of a magnetic field, with the temperature of the superconducting material above the critical temperature, the field freely penetrates the superconductive material. As the temperature drops below the critical temperature, the superconductive material transitions into the superconducting state and expels the magnetic field.
As the temperature rises above the critical temperature, the superconducting material transitions back to the normal state and the magnetic field returns to penetrate the superconducting material volume.

Superconductor device to produce electrical impulses

The United States of America as represented by the Secretary of the Air Force


In a joint prosthesis with a base piece for anchoring in the bone, a collar piece articulated thereon and defining a collar axis, and a collar extension on the collar piece situated on the collar axis, an articulation space is formed on the base piece. An articulation head of the collar piece is disposed therein. The joint prosthesis further includes a head cap disposed on the collar extension and at least one pressure piece for pressing the articulation head against the base of the articulation space. The pressure piece and the base piece can be connected. In a joint prosthesis of this kind, the pressure piece includes a pressure disc with a passage opening for the collar extension.

1. Field
The invention relates to a joint prosthesis with a head cap articulated in the manner of a ball joint via a collar piece on a base piece for anchoring in the bone.
2. Background Information
From EP-A-0 663 193 a hip joint socket is known which is held by a holding ring in a supporting shell on an anchoring plate fixed on the bone. In order to prevent any rotation of the hip joint socket in the supporting shell, penetration elements are provided in the supporting shell. If the hip joint socket is now pressed into the supporting shell by a setting instrument with the application of force, the penetration elements penetrate the relatively soft plastic material of the hip joint socket. The holding ring is then brought into the correct position to hold the hip joint socket in the supporting shell.
From WO 99/34756 a shoulder prosthesis is known wherein a collar piece is articulated in a hemispherical recess in the shaft piece, the collar piece being pivotable therein in the manner of a ball joint. The collar piece has a hemispherical articulation surface and a conical surface which is eccentric in relation to an axis through the ball center of said articulation surface, said conical surface being intended for the fitting of a joint cap. The collar piece has a bore which is open from the cap side and which has a hemispherical base. A screw with a spherical head introduced into the bore and adapted to be screwed into the shaft piece through an opening in the base of the bore, co-operates with the base. The spherical surfaces of the hemispherical recess in the shaft piece, of the articulation surface on the shaft piece, of the base of the bore and of the screwhead must have the same center point. In addition, each pair of co-operating hollow and solid spherical surfaces must be made very accurately and have the same radius. Minimal deviations from the ideal measurements have the effect that the collar piece cannot be connected sufficiently firmly to the shaft piece in order to reliably prevent unintentional pivoting of the collar piece relatively to the shaft piece during the use of the joint.
From EP-A-0 712 617 a humeral head prosthesis is known wherein an articulation ball connected to a head cap via a shank is articulated on a shaft piece in a cavity with a hollow spherical base. To fix the articulation ball in the cavity, one or more grub screws are provided which can be screwed through the shaft piece against the articulation ball. In one exemplified embodiment, the articulation ball, which is of cut-open C-shape, is pressed together by the grub screw in order to clamp therein the shank which fits in a central bore in the articulation ball. In another exemplified embodiment, a grub screw is provided which can be screwed along the shank axis through the articulation ball and against the cavity base. With this screw the articulation ball is pressed against the opening of the cavity, which opening in this exemplified embodiment has a smaller radius than the spherical radius of the cavity and the articulation ball.

This patent is subject to a terminal disclaimer.


A transceiver for radio-frequency communication comprises a waveguide, a transmitting port, a receiving port and a receiver load termination. The waveguide receives and transmits radio-frequency signals. The transmitting port is connected to the waveguide and transmits the radio-frequency signals to the waveguide. The receiving port is connected to the waveguide and receives the radio-frequency signals from the waveguide. The receiver load termination is connected to the waveguide and removes the vertical polarization components of the receiving radio-frequency signals. The receiver load termination includes a filtering unit to reduce the energy of the transmitting radio-frequency signals entering the receiver load termination.

(A) Field of the Invention
The present invention relates to a radio-frequency communication transceiver, and more particularly, to a radio-frequency communication transceiver with a receiver load termination.
(B) Description of the Related Art
Conventional radio-frequency (RF) transceiver design comprises a waveguide to receive an RF signal, which is then processed by an analog processing unit, such as an analog IC. The RF signal is then further processed by a digital processing unit, such as a digital IC.
In conventional RF communication systems, such as an RF satellite transceiver, the receiving signals are received at an IO port of a waveguide, conducted to a receiving port, and then forwarded to an analog processing unit. For transmitting, on the other hand, the transmitting signals are outputted from the analog processing unit via a transmitting port to the waveguide and then are conducted to the IO port of the waveguide.
However, the vertical polarization component of the receiving RF signals should be removed to prevent RF transceivers from malfunctioning while receiving RF signals. Therefore, conventional RF transceivers may further comprise a receiver load termination to remove the reflecting signals of the receiving RF signals. The receiver load termination can remove the polarized signals perpendicular to the receiving RF signals.
When RF transceivers transmit RF signals, however, some portions of the transmitting RF signals may pass the receiver load termination to cause energy loss of the transmitting RF signals and the quality thereof is jeopardized. Therefore, there is a need to design an RF transceiver to reduce the energy loss of the transmitting RF signals.

Transceiver for radio-frequency communication


An improved snowshoe is provided which includes a unitary molded planar platform and a peripheral curved lip extending away from the platform. Integral with the underside of the platform is a plurality of stiffening ribs to provide support to the platform. Retaining straps are provided for securing a wearer's foot to the snowshoe platform. A plurality of slots are formed through the platform which enables snow trapped on the surface of the platform to fall therethrough. In a first embodiment, the slots also serve as anchor points for selective placement of the retaining straps and selective positioning of the foot on the platform. Based upon the wearer's desire, the straps may be arranged in a number of different combinations and selectively adjusted to accommodate the particular type of foot gear worn. A second embodiment enables the platform to receive either a cross-country ski binding or a snowboard binding. A third embodiment discloses a snowshoe having a binding especially adapted for use by children. A fourth embodiment discloses the snowshoe platform being usable as a shovel by attaching a handle thereto. A fifth embodiment incorporates the use of a binding having a rotatable metatarsal strap which can also be selectively removed or adjusted.

Many types of designs exist for snowshoes. Each of these designs usually incorporates one or more features which are intended to achieve a specific advantage relating to use of the snowshoe for a specified purpose.
One example of a prior art snowshoe designed to achieve a specific advantage is U.S. Pat. No. 3,673,713 to Fedewitz. This invention teaches a snowshoe made of injection molded polypropylene wherein the tread of the snowshoe has a plurality of resiliently hinged flaps angled downwardly as measured from a horizontal. The flaps are intended to help the snowshoe wearer remain on top of snow when worn, but also to help remove snow collected on the upper surface of the snowshoe when the snowshoe is lifted above the snow. The foot of the snowshoe wearer rotates about a hinge point on the snowshoe located near the ball of the foot.
U.S. Pat. No. 3,299,541 to Snyder teaches a snowshoe including tread formed of plastic material, and further having harness engaging means formed upon an integrally connected hinge portion. A toe aperture portion formed in the forward portion of the snowshoe tread enables a wearer's foot to rotate about a hinge point located near the ball of the foot. In use, the foot rotates about the hinge point such that the entire foot, except for the toe portion, rises above the snowshoe platform.
U.S. Pat. No. 3,638,333 to Sprandel discloses a molded plastic snowshoe including a frame with webbing therebetween, and a transversely extending pivot with a horizontal opening defined in the snowshoe immediately in front of the pivot. A one-piece molded plastic harness includes two straps which encircle the pivot and extend around the rear of a boot, and a third strap that forms a loop to receive and hold the toe of the boot. Thus, the harness pivotally engages the boot on the snowshoe and the opening in the snowshoe allows the toe of the boot to pass therethrough during perambulation.
U.S. Pat. No. 4,213,256 to Mas, et al. discloses a snowshoe comprising a flat member which is bisymmetric in that its upper and lower sides are mirror images of each other. A portion of the snowshoe supporting the foot is displaced toward the inner side of the snowshoe, and the laterally outer portion comprises an open gridwork supported by a frame, the whole snowshoe being of a molded plastic construction. The portion of the snowshoe supporting the foot is provided with holes adjacent the margins of the foot or shoe of the user; and a single lace can be inserted through these holes to provide front and rear bindings for the foot or shoe.
While each of these prior art inventions may be adequate for their intended purposes, none of the prior art devices include advantages of the present invention which will become apparent through the disclosure provided herein. One advantage of the present invention over the prior art is that means are provided to enable a user of the snowshoe to wear a number of differing types of foot gear. That is, a user of the present invention is not restricted to use of a particular size or style of footwear. Another advantage over the prior art is that during perambulation, the rotation of the wearer's foot occurs at the very front edge of the snowshoe which enables the wearer to obtain better gripping action on frozen snow or ice. This positioning of the point of rotation at the front edge of the snowshoe also enables a wearer to achieve a more natural walking motion as opposed to traditional snowshoes which require a wearer to lift the snowshoe after the foot has pivoted. Another advantage over the prior art is that the foot may be selectively positioned on the snowshoe depending upon the wearer's choice and the environmental conditions in which the snowshoe is used.
The improved snowshoe of this invention also provides a means by which the snowshoe can receive either a cross-country-type ski binding or a snowboard-type binding. Often times, snowboarders and cross-country skiers desire to conduct their sporting activities in remote locations which are only accessible by hiking into such locations. Accordingly, the improved snowshoe of this invention enables a cross-country ski boot and/or snowboard boot to be directly attached to the snowshoe in a secure manner which does not degrade the ability to effectively snowshoe in such locations. Cross-country ski boots and snowboard boots typically have portions which extend from the toe and/or heel of the boot. Also the construction of these boots is designed for use with a specific type of binding which provides the wearer a particular type of locomotive capability with respect to cross-country skiing/snowboarding. If these type of boots are used in snowshoes such as disclosed in Sprandel, the toe portions of these boots can become clogged with snow and can significantly degrade the use of the snowshoe since the toe portion may extend too far into the snow. Even if the cross-country ski boot and/or snowboard boot are used in conjunction with snowshoes of the type disclosed in Snyder, effective snowshoeing is degraded since the boot cannot be adequately locked/secured to the snowshoe. Because of these shortcomings with respect to prior art snowshoes which are not well adapted to receive a cross-country ski boot or snowboard boot, the skier or snowboarder may be forced to carry additional foot gear solely for the snowshoeing activity.
Because of the compact size of the snowshoe of this invention, it can be easily carried within a backpack worn by the skier or snowboarder. Even when the cross-country skier or snowboarder is not faced with hiking into a remote region, the ability to attach the boot directly to the improved snowshoe of this invention is advantageous. Deep snow and difficult terrain can be found in many areas which may require the cross-country skier or snowboarder to employ snowshoes.


A treadmill exercise device includes two side frames with a plurality of connecting bars connected therebetween. A board is disposed onto the two side frames. Two first supports are respectively disposed to two respective first ends of the two side frames and two second supports are respectively disposed to two respective second ends of the two side frames. A first roller is rotatably disposed between the two first supports and a second roller is rotatably disposed between the two second supports so that a belt is movably wrapped around the two rollers with the board disposed therebelow.

1. Field of the Invention
The present invention relates to an exercise device and, more particularly, to a treadmill exercise device having a better structural strength and an adjusting device which is easily to be operated to adjust a tensile force of the belt.
2. Brief Description of the Prior Art
A conventional treadmill exercise device includes two side frames between which two rollers are separately and rotatably disposed, an endless belt wrapped around the two rollers so that a user can run on the belt. In order to support the user's weight during using the treadmill exercise device, a board is inserted between the two side frames and the belt. However, a certain thickness and stiffness of the board are required so as to sufficiently support the user's weight. The board increases a total weight of the treadmill exercise device.
The present invention intends to provide an improved treadmill exercise device to mitigate and/or obviate the above-mentioned problems.


Methods and systems are provided for lubrication of a transmission. In one example, the transmission system may include a pair of shielded bearings attached to a first transmission shaft, each of the shielded bearings including at least one shield that forms a restriction between the shield and a race of the bearing and a cavity positioned axially between the pair of shielded bearings, wherein the restrictions tune lubricant pressurization in the cavity. The transmission system further includes a radial passage in the first transmission shaft in fluidic communication with the cavity and a lubricated transmission component.

Vehicle transmissions include moving components that can generate friction and heat, correspondingly, during operation, such as bearings, gears, and the like. In order to deliver oil to these components, transmissions have employed lubrication systems that route oil through a gearbox to lubricate selected components and decrease component wear. Efforts have been made to deliver oil to a variety of geartrain components which may be tightly packaged and difficult to sufficiently lubricate. Certain transmissions have utilized a dedicated oil distribution manifold in an attempt to pressurize the oil to drive oil flow to components throughout the transmission.
U.S. Pat. No. 5,366,419 A to Oda, for instance, teaches a transmission in a vehicle with a lubrication system within a transmission casing that includes an oil path with a shielded bearing designed to form an oil sump between a seal and the bearing on an output shaft. The shielded bearing and resulting oil sump collect oil due to gravitational forces. Further, other oil paths within the system serve to deliver oil to various portions of the transmission assembly, particularly by routing oil through central bores in multiple shafts for splash lubrication. However, Oda's transmission lubrication system does not include a pump and instead relies solely on splash lubrication to deliver oil to the transmission components.
The inventors have recognized several issues with Oda's lubrication system and other transmission lubrication arrangements. For instance, the system disclosed by Oda may not be capable of pressurizing oil to direct the oil to space-constrained areas of the transmission, as it relies on centrifugal forces to drive oil flow rather than using a pump and pressure regulating assembly for distributing oil. In particular, Oda's system does not offer an efficient method for strategically regulating the supply of lubricant based on the lubrication demands of a given system. Additionally, the reliance of Oda's transmission lubrication system on splash lubrication for oil circulation causes undesirable churning losses. Further, in lubrication systems utilizing an oil distribution manifold, tight tolerances for the manifold and surrounding components may be demanded for effective installation. Consequently, manufacturing and installation of the distribution manifold may be complex, time demanding, and costly.
To resolve at least a portion of the aforementioned issues, the inventors have developed a transmission system that includes a pair of shielded bearings attached to a transmission shaft. In the system, each of the shielded bearings include at least one shield that forms a restriction between the shield and a race of the bearing. The system further includes a cavity positioned between the pair of shielded bearings. The restrictions in the bearings enable lubricant pressurization within the cavity. The shielded bearings may therefore be configured to deliver a smaller portion of lubricant through the bearings to a lubricant seal, and to deliver a larger portion of oil to a bore in the transmission shaft, via a radial passage formed therein, to provide a greater amount of lubricant to moving components within a gearbox. Specifically, the axial bore of the transmission shaft is in fluidic communication with at least one lubricated transmission component. In this way, the shielded bearings provide a dual-use functionality: pressurizing lubricant in the cavity; and permitting transmission shaft rotation. By increasing the pressure of lubricant in the cavity, components which may be tightly packaged in the transmission, such as gears in a planetary gearset, may receive greater amounts of lubricant than previous systems. Consequently, transmission longevity may be increased.
As one example, to achieve the lubricant pressurization in the cavity, each of the shielded bearings may include a shield positioned on an axial side thereof. In such an example, each shield extends from an outer race of the corresponding bearing towards an inner race and forms the restriction. In this way, the shielded bearings may be contoured to achieve the dual-use functionality.
In another example, to achieve the lubricant pressurization in the cavity, at least one of the restrictions is at least partially formed by an annular plate that is fitted to a bearing bore in a housing of the transmission on an axial side of the corresponding shielded bearing spaced away from a lubricant inlet. In this example, the annular plate has an inner gap that defines the restriction between the annular plate and the transmission shaft. In this manner, an annular plate may be used to tune lubricant pressurization in the cavity to drive lubricant flow to tightly packaged components, for instance.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

Transmission lubrication system with shielded bearings


Method of monitoring water conservation in an apartment complex by positioning infrared cameras with motion sensors in the clean outs of the waste water discharge lines leading to public sewer systems wherein each camera image is displayed on a computer screen and the motion sensors, which start and stop the digital video recorders (DVR), are adjusted by circumscribing the area of the camera image and the pixel sensitivity setting for motion sensors activation, which triggers the DVR recordings. In this arrangement the intermittent or constant flow of waste water is detected in real time indicating normal or abnormal flow of waste water, respectively. Further, an infrared camera may be positioned on the apartment complex side of the water meter to determine in real time if water is being supplied to the complex and the waste water flow out is little or none then loss of water outside the plumbing system from overflowing commodes, tubs, lavatories or broken pipe is indicated.

1. Field
This invention relates to a method and system of sewer scanning for monitoring fluids, primarily water being discharged from a building through a series of drains and uncontained flow from drain system failures or accidents. Furthermore, the invention provides for monitoring and control of the fluid or water sources in single or multi-family residential structures to prevent overflow and backup of uncontrolled water discharge.
2. State of the Art
Various systems for monitoring water or fluid flowing in fluid discharge conduits have been proposed to determine flow rates and volumes, and/or to determine backups or overflow of water in the systems.
Alarm systems for sewer lines have been utilized in the past for detecting blockage or backup by use of pressure sensors in the access or clean out sections of sewer lines. The majority of such arrangements determine the currents or some unusual stoppage but fail to identify the location of the particular uncontrolled discharge, such that the problem area can be detected and corrected before substantial problems or damages occur. Most of the monitoring of the water supply to buildings and residential dwellings are usually provided by well known water metering systems, which determine the volume of water entering the structure.
One of the problems in the existing systems of monitoring water discharges from structures is lack of correlation between the water supply to the structure and the volume discharged through drain and sewer lines; thus back up of commodes, sinks, utility room overflows are not detected by input meters or sewer discharge monitors, thus flow onto the bathroom floor from sinks or commodes could go undetected for extended periods of time when the occupants are not present.
Various metering systems for water discharge systems are known in the art. U.S. Pat. No. 5,942,698 issued to Stevens describes a virtual sewer flow monitor that detects flow rate and depth periodically and supplies it to a scatter graph generator and a polynomial curve generator therefore. A filter eliminates polynomial curve corresponding to normal sewer flow and an SSO detector responds to curve portions indicating an overflow to generate an alarm.
U.S. Pat. No. 5,006,833 issued to Marlowe, et al. teaches a sewer line restriction alarm placed in the clean out which includes a diaphragm which moves in response to the restriction and sets off an alarm.
U.S. Pat. No. 4,973,950 issued to Tourtillott discloses a sewer blockage alarm having a pressure sensor in the top of a clean out branch section that is connected to a large diameter pressure multiplying pressure bell. This arrangement set off a visual and audible indicator warning of a down stream blockage of a residential plumbing system to avoid a backup into the residence.
U.S. Pat. No. 4,407,158 issued to Petroff discloses a flow measurement system wherein separately located monitors record synchronized and time identified pressure measurements with pressure-to-signal transducers on the bottom of pipes. A recorder records the pressure each signal and monitor identity which is furnished to a pressure-to-flow computer which provides location identified, time synchronized, flow data for the system.
U.S. Pat. No. 5,862,775 issued to Stroud discloses a riser system with an inflatable balloon with a flag. The balloon can be inflated or deflated without removing the sewer cover. The flag rises with the balloon indicating a possible back-up of the sewer line.

Method and system of sewer scanning for water conservation


A local oscillator provides an in-phase local oscillating signal and quadrature-phase signal to first and second mixers outputting an input signal with a mixed in-phase local oscillating signal and quadrature-phase local oscillating signal, respectively. The oscillator comprises a local oscillator having first and second delay cells and outputting said in-phase local oscillating signal and said quadrature-phase local oscillating signal; and a correction circuit for controlling phase matching characteristics, said correction circuit setting bias current flowing in said first and second delay cells of said local oscillator as being to be different. In another embodiment, the phase matching characteristic is controlled by setting the bias voltage applied to the first and second delay cells as being to be different, by setting the width of the active device included in the first and second delay cells dells as being to be different, or by setting impedance of passive device to be different.

FIG. 1 shows a schematic circuit diagram of the conventional radio frequency receiver.
As shown in FIG. 1, the conventional radio frequency receiver comprises a low-noise amplifier 110, first and second mixers 120, 130, a local oscillator 140 and first and second base-band circuits 150, 160.
Low-noise amplifier 110 amplifies radio frequency signal received by an antenna to apply the signal to first and second mixers 120, 130. First and second mixers 120, 130 mix the amplified radio frequency signal with in-phase local oscillating signal LOI and quadrature-phase local oscillating signal LOQ to output intermediate frequency or base band signal, respectively. First and second base-band circuits 150, 160 amplify/filter the signal outputted from first and second mixers 120, 130, respectively to output in-phase signal I and quadrature-phase signal Q.
In radio communication system, radio frequency receiver transmits data by carrying it in in-phase channel and quadrature-phase channel. Thus, in order to restore signal completely, in-phase local oscillating signal LOI and quadrature-phase local oscillating signal LOQ are necessary. If the difference between the phases of LOI and LOQ does not equal 90 degree, bit error rate increases in the restored signal. In particular, tile mismatch between in-phase signal I and quadrature-signal Q causes significant problem in the system of direct-conversion receiver and image-removing receiver.
However, the characteristic of delay cells of the local oscillator does not ideally match due to thickness of insulator, device size, space difference, various crystal structure of semiconductor material, mismatch of layout and the like. Such a mismatch of delay cells causes mismatch between in-phase local oscillating signal LOI and quadrature-phase signal LOQ outputted from the local oscillator. This is an important cause of generating mismatch between I/Q signals of the receiver. Further, mismatch between devices in way of I and Q path of the receiver is one of causes generating I/Q mismatch of radio frequency receiver.
As clearly understood from a person skilled in the art, size mismatch between in-phase signal I and quadrature-phase signal Q is not significant cause. However, phase mismatch may cause significant problem due to path difference between two signals and device characteristic as frequency increase.
In conventional art, the phase mismatch is corrected with compensation of in-phase signal I and quadrature-phase signal Q of base band that pass a mixer or with compensation of the paths of radio frequency signals I and Q. However, these corrections require additional correction circuit in signal path. The addition of correction circuit to a path where signal passes may degrade gain, noise, linearity and the like. Further, it is difficult to apply the technique in already-manufactured circuit,

Local oscillator using I/Q mismatch compensating circuit through LO path receiver using thereof


An electronic writing solution server includes a classification application that comprises a classifier and a user interface engine. The classifier receives multimedia data on a form, identifies at least one field in the form to be modified and modifies the at least one field in the form based on the multimedia data. The user interface engine provides the modified form to a user.

1. Field of the Invention
The specification relates to processing of forms. In particular, the specification relates to modifying a form based on classifying and identifying multimedia data received on the form.
2. Description of the Background Art
People fill out forms for a wide variety of purposes. As paper usage is reduced, an increasing number of forms are provided in electronic form and an increasing amount of information is included in the electronic forms. For example, a student may fill out all forms related to school activities. The forms could be admission application forms, class selection forms and graduation application forms. Each form contains a large amount of information. The admission application forms include a summary of a student's past school years, the class selection forms change every semester and the graduation application forms include the student's academic achievement. This tendency for using forms does not stop with school. Users need to fill out forms to get medical services, to buy a car, to get a mortgage, to obtain insurance, etc. Currently, the process is complex and time-consuming.
Some attempts have been made to reduce the number of fields that the user has to fill in. For example, there are browser extensions for saving a user's personal information, such as name and credit card number to make filling out forms for purchasing objects easier. However, these applications frequently insert the wrong information into fields and they can only insert information into fields that are the same as a previous form, for example a name, which reduces the usefulness of the applications.

Form filling based on classification and identification of multimedia data


Television system targeted advertising is described. In an embodiment, a content provider monitors a real-time state of television-based systems for a power on/off state and a tuning configuration. The content provider delivers advertising content to one or more of the television-based systems when they are powered-on and configured to receive the advertising content. The one or more television-based systems then receive the advertising content to display a targeted advertisement for viewing. The content provider records how many of the television-based systems receive the advertising content, and records how many of the television-based systems that receive the advertising content then display the targeted advertisement for viewing.

For broadcast television, it is difficult to measure or qualify the impression that an advertisement has on viewers who see the advertisement. Typically, advertisements are inserted into television channels that are broadcast globally to subscribers of a television service. Additionally, global advertisements can be replaced with region specific advertisements for local advertising to viewers of a particular region. However, there is no guarantee that region specific advertisements targeted to a particular subscriber group are actually watched by the viewers of the group. Subscriber television devices may not be powered on to receive the advertisements when they are delivered, or the television devices may be powered on but tuned to a television channel other than the one over which a targeted advertisement is delivered.
Advertisers typically rely on marketing assumptions based on historical data, such as historical logs of subscriber device inputs, to provide an approximate measure of advertising impressions on viewers. Targeted advertisements are delivered to a particular group having viewers that are more likely to buy an advertised product or service. Television service providers desire information about targeted advertisement impressions because targeted advertisements can command a premium price for their delivery to a targeted subscriber group. However, the current methods of targeted advertisement tracking only provide post-device state information, such as the number of subscriber television devices that were powered on to receive a targeted advertisement. These types of advertisement impressions after the fact do not provide enough of a basis to deliver the targeted advertisements and/or to command a premium price for the delivery of the advertisements from advertisers wanting to target viewers that are most likely to purchase a product or service.


A low-profile, axial-flow, single-blade piezoelectric fan is provided. The fan is in the form of a piezoelectric fan assembly (300) which contains a housing (302) defining an axial flow-through internal cavity. Inside the housing (302) is a single fan blade (314) which is attached at only one end to the housing (302). A piezoelectric element (318) is fixedly mounted to the single fan blade (314) and causes the single fan blade (314) to deflect when the piezoelectric element (318) is activated. This piezoelectric fan assembly (300) may be used to cool electronic components in applications where low-power and low-volume fanning is desired.

The use of fans for blowing air over an electronic circuit board for cooling purposes is well known in the art. Typically, this is accomplished using either piezoelectric or rotary type fans.
Rotary type fans have many drawbacks. They require many moving parts including bearings, which necessarily require some type of lubrication. Rotary fans also have typically larger size and power consumption requirements than piezoelectric fans and rotary fans may generate significant electromagnetic interference (EMI) and radio frequency interference (RFI) noise signals. Additionally, rotary fans oftentimes have a shorter life than piezoelectric fans.
Piezoelectric fans have been used as an alternative to rotary fans and offer significant advantages in that they have fewer moving parts, generate very little heat, and can be used in harsh environments with wide temperature ranges, wide humidity ranges, or even in hazardous and explosive gas conditions.
Prior art piezoelectric fans have typically been manufactured using a dual-blade design. The two bender blades are typically oscillated 180 degrees out of phase with each other. The complementary back and forth motion of the two blades provides dynamic balancing and also minimizes vibration and noise in the device. Unfortunately, dual-blade piezoelectric fans have a profile (height above a circuit board) which is unacceptably high for many applications.
FIG. 1 shows a dual-blade piezoelectric fan 100 in accordance with the prior art. In FIG. 1, a housing 102 supports two fan blades 104 and 104' which are driven 180 degrees out of phase with each other. Piezoelectric elements, internal to the housing 102, are activated by a pair of lead wires 106, 106'. The air flow patterns around the blade 104' are represented by arrows which show the air flow in and out of fan 100. Prior art fans, such as the one shown in FIG. 1, have a very high profile and also consume a large volume of space. Although they may be readily used in applications where space restrictions are not an issue, they are ill-suited for cooling densely packed electronic components in modern electronic products.
FIG. 2 shows another embodiment of a flat dual blade piezoelectric fan 200 found in the prior art. Fan 200 contains two fan blades 202, 202' which are separated by a mounting beam 203. Each of the fan blades contains a piezoelectric element 204 which is driven to cause deflection in the fan blades 202, 202'. An electrical current activates the piezoelectric elements and this is shown in FIG. 2 by positive and negative lead wires attached to element 204.
The air flow patterns around the fan blades are represented by arrows which show the air flow in and out of the fan. The primary airflow in occurs at the corners of the fan 206 and the secondary airflow in occurs along the side edges of the fan 208. The air flow out of the fan occurs at an end of the fan 210 opposite the mounting beam 203.
Piezoelectric fan 200 also has significant design drawbacks. The airflow in fan 200 is non-axial and, as such, substantial volume is needed for ducting purposes. Additionally, the height of the dual-blade design may be restrictive for certain applications.
Consequently, a low-profile single-blade piezoelectric fan which offered a low-power, low-noise, low-cost, and low-vibration design and which could provide a sufficient axial flow to cool electronic components in a rugged, customized housing assembly which provided for smaller overall dimensions in electronic products would be considered an improvement in the art.

Low-profile axial-flow single-blade piezoelectric fan


Disclosed are systems, devices, and methods for additive manufacturing that allow for control of composition and/or porosity of components being manufactured. More particularly, in exemplary embodiments, a secondary material can be used in conjunction with a primary feedstock material in a spatially controlled manner during an additive manufacturing process to control a composition of materials and/or porosity of a manufactured component. Systems, devices, and methods for additive manufacturing are also disclosed that allow for control of a pressure of an atmosphere surrounding a build surface during an additive manufacturing process. More particularly, a pressure of an atmosphere surrounding a build surface can be raised to a pressure greater than standard atmospheric pressure. Various features of the exemplary embodiments of the systems, devices, and methods disclosed can be used together to further control for composition and/or porosity and quality of a manufactured part.

Additive Manufacturing (AM) has become a central technology for rapid prototyping and short run manufacturing. Selective laser melting (SLM) is perhaps the most ubiquitous method for metal AM. From early machines to the most sophisticated machines available today, there are four components used in SLM/Selective Laser Sintering: a build stage, powdered build material, a recoating system, and a steerable laser power source. A simplified model of an SLM machine 10 can be seen in FIG. 1. The SLM machine 10 includes a vertical motion stage 12 that positions a build platform 14, on top of which a three-dimensional part 16 is constructed. A recoater 18 is coupled to the build platform 14 and a powder well (not shown). The recoater 18 is used to distribute a thin, even coating of a powdered build material drawn from the powder well over the build platform 14 creating a build layer. A steerable laser source 20 is used to selectively melt the build material in each successive build layer to create a desired three-dimensional part.
The process of building a part using the SLM machine 10 begins with the recoater 18 spreading a thin, typically 50 μm to 100 μm, layer of the powdered build material across the build platform 14. The steerable laser system 20 then melts select parts of the newly coated layer of powdered build material by directing the laser energy at the desired location(s) and forming a melt pool of the molten build material. As the laser energy is removed from the desired location(s) the molten material solidifies. Once the selective melting is complete, the build platform 14 is lowered an amount equal to a layer height of the system by the vertical stage 12, and the recoater 18 deposits a new layer of build material. This layer-wise process repeats until the entire part has been built.
To build at a certain rate and/or achieve a melt pool of a specific diameter and depth traveling at a desired speed, there has to be a requisite energy input into the system to melt the build material and form it into a solid feature integrated into the layer below it. This can happen through the formation of a melt pool at the laser-build material interface, and the transfer of energy from the laser into the melt pool, and then into the surrounding material. Due to thermal resistance, a temperature gradient can form over the melt pool. The build material can be right at its melting point at the edge of the melt pool, and the temperature can increase towards the laser contact region. The faster a part is constructed, the greater the energy transfer across that resistance, which gives rise to a higher temperature gradient. The dynamics of the melt pool and stability of the melt track upon cooling can be critical to the microstructure, porosity, and final properties of the solidified material.
If material in the laser contact region becomes too hot, exceeding the boiling temperature of the build material, or of certain alloying elements within the build material, the material can begin to vaporize, forming jets of gas, high-velocity convection currents, and vapor condensate plumes. This can push and distort the melt-pool and interfere with the laser absorption at the build layer, leading to poor performance.
The dynamics of the AM process constrain the use of powder-bed AM devices and methods, such as the SLM printer described above with respect to FIG. 1, to a small catalogue of materials when compared to traditional manufacturing processes. The use of high temperature energy sources and reliance on melting of a material during the AM process can dictate material selection. Generally, powder-bed AM printing materials are limited to derivatives of titanium, stainless steel, nickel, and cobalt. For example, magnesium, the third most popular structural metal, is commonly used in traditional manufacturing processes, but is not typically suitable for AM printing due, at least in part, to the thermal properties of magnesium.
Moreover, AM components can generally be manufactured only as high-density parts. The minimum feature size of an AM fabricated part can be limited by powder material and size distribution characteristics, as well as the diameter of a laser spot on the powder bed. Accordingly, to achieve variation in component properties, particularly on fine length scales, a part usually must be specifically designed with the appropriate geometry (e.g., a lattice structure design). This is a labor-intensive process and results in slow manufacture times. For example, hollow architectures must all be open-cell due to requirements of removing extra powder or support material. Moreover, to attain low density, lightweight parts (and those with tune-able properties, such as stiffness), print jobs are currently designed with open-cell lattice structures with length scales based on these feature size limits.
Accordingly, there is a need for systems, devices, and methods of manufacturing a three-dimensional component with AM that allow for wider material selection, improved part performance, and control of component characteristics.

Spatial porosity and composition control in additive manufacturing