An earth moving machine attachment is disclosed comprising a plurality of disk units mounted to a disk unit mounting beam which is fixed to a beam pushing frame for pivotally coupling to a dozer or tractor C frame. The beam pushing frame is angled obtusely in a clockwise or counterclockwise direction from the direction of push by a pair of reciprocal operating hydraulic cylinders to grade the earth materials to one side or the other of the C frame. The disk unit mounting beam and attached disk units are hingedly connected to a parallel offset shaft of the beam pushing frame for tilting the disk blades to provide restricted floatation on the earth materials. A sliding feature of the hinged connection between the disk unit mounting beam and the beam pushing frame accommodates hydraulic power means of shifting the load relative to the pushing axis of the earth moving machine. In operation, each disk blade of the attachment excavates a ribbon of earth materials and discharges these materials laterally with a high momentum as determine by the speed of the earth moving machine. The angled arrangement of the sequential disk units grades the earth materials to one side or the other of the C frame depending on the set angle of the beam pushing frame. A hydraulic power means of setting the pitch angle of the disk blades for optimum excavation and grading is provided by an articulated embodiment of the plurality of disk units mounted as a gang relative to the disk unit mounting beam. The device is designed as an efficient blade attachment for rough excavating and grading of earth materials including snow using earth moving machines.

1. The Prior Art
Dozers, road graders, and agricultural tractors have conventionally used rectangular shaped blades for excavating, pushing and grading earth materials including snow. Many of these blades have been disclosed in patents, and the following are exemplary of the types of patents issued in this class; U.S. Pat. No. 4,464,852 to Rice, U.S. Pat. No. 4,445,577 to Russell D.E. and Russell T.H., U.S. Pat. No. 4,306,625 to Davis, U.S. Pat. No. 4,554,978 to Schneider, U.S. Pat. No. 4,135,583 to Becker, and U.S. Pat. No. 3,853,181 to Yoshizaki.
Multi-blades and articulated blades such as those disclosed by U.S. Pat. No. 4,834,191 to Vecchio, U.S. Pat. No. 4,758,116 to Ezoe, U.S. Pat. No. 4,384,620 to Uchida et al., U.S. Pat. No. 4,270,617 to Cantarella and Cecchi, U.S. Pat. No. 4,099,578 to Stevens, U.S. Pat. No. 4,029,157 to Freese, and U.S. Pat. No. 4,019,587 to Meisel, have also been invented to aid in the excavation, pushing, and grading process for various earth materials. All of the prior art blade inventions, including the multi-blade and articulated blades, use contiguous blade or contiguous multi-blade designs with large surface areas in continuous contact with the excavated materials. Although the contiguous blade design ensures that the earth materials are smoothly graded along the surface of the earth, a contiguous blade is not necessary for performing rough excavating and grading of earth materials. Many applications such as initial road bed construction, terrace construction on farmland, waterway construction, ditching, diking and open pit mining do not require a smooth finish to the earth materials after each pass of the earth moving machine. For these types of rough excavating and grading applications, the efficiency of the earth moving machine is improved by using discrete disk blades for excavating ribbons of earth materials and discharging these materials laterally with high momentum. Frictional forces associated with shifting earth materials along a contiguous blade are significantly reduced with discrete disk blades, particularly if the earth moving machine has sufficient horsepower to maintain a speed of at least five miles per hour. Only the last disk blade of a plurality of disk grading units is constrained to grading materials in a manner analogous to conventional earth moving blades.
My invention describes a rough excavating and grading attachment using discrete disk blades laterally spaced along a beam which can be attached to conventional dozer C frames such as disclosed in U.S. Pat. No. 4,167,979 to Freese and Wheeler, attached to frame assemblies for power machines such as disclosed in U.S. Pat. No. 4,306,625 to Davis, attached to agricultural dozer frames such as disclosed in U.S. Pat. No. 4,304,305 to Bartel or attached to other types of tractive pushing frames. The U.S. Pat. No. 4,597,452 issued to Tapphorn R.M. and Tapphorn D.E., is exemplary of the class of discrete disk blade graders, however, the disk grading terrace plow cited in the referenced invention is restricted to towing in its application and claims.


A presser foot and needle drive device in an embroidery machine includes a drive mechanism and a control device for vertically reciprocally moving a presser foot between upper and lower dead center. The control device operates the drive mechanism according to patterns of presser foot movements which are determined for specific sewing conditions.

1. Field of the Invention
The present invention relates to a presser foot drive device in a sewing machine.
2. Description of the Prior Art
Conventionally, two types of presser foot drive devices have been proposed for vertically reciprocally moving a presser foot in a sewing machine. One type of the devices is constructed to move the presser foot in response to movement of a needle bar, and the other type is constructed to move the presser foot independently of the needle bar. In case of the latter type, the rotation of a main shaft for driving the needle bar and a shuttle is converted into the reciprocal movement of the presser foot by a cam mechanism or a link mechanism.
In the prior art presser foot drive devices, even if they are of the latter type for independently driving the presser foot, the stroke of vertical movement of the presser foot as well as the timing of its vertical movement relative to the movement of the needle bar is substantially fixedly determined by the design of the sewing machine. Thus, the presser foot is moved regardless of the sewing situation or the material of a work fabric. This may produce unpleasant vibrations or noises or may cause breakage of a sewing thread.

Presser foot and needle drive device in an embroidery machine


An aircraft (1) having an airframe (2) extending along an anteroposterior plane of symmetry (P1) in elevation transversely separating a first side (11) of said aircraft (1) from a second side (12) thereof, said aircraft (1) being provided with hoist means (20) including a winch (21) provided with a drum for winding a hoist cable (22), said hoist means (20) including a beam (30) for guiding said cable, said beam (30) extending from a first end (31) constituting an inlet end for said cable (22) to a second end (32) constituting an outlet end for said cable (22). The hoist means (20) have a counterweight (23), said counterweight including said winch (21) that is fastened to said first end (31), said second end (32) being located on said second side (12) while said winch (21) and said first end (31) are located on said first side (11).

(1) Field of the Invention
The present invention relates to an aircraft provided with hoist means, in particular a rotary wing aircraft, and also to the associated method.
Conventionally, hoist means comprise a winch arranged above a cabin of a rotary wing aircraft, for example, such a winch having a rotary drum for winding in and out a cable that serves in particular to lift or transport an external load.
The winch is arranged on a flank of the aircraft, e.g. above a cabin.
That type of installation is nevertheless limiting on light aircraft. When the winch carries a heavy load, e.g. of the order of 150 kilograms (kg), the aircraft tends to tilt with a roll movement towards the side of said load. In addition, there is a particularly large impact on centering the aircraft.
Under such circumstances, a light helicopter provided with a winch on a side flank is capable of carrying only a relatively small load, e.g. less than 150 kg, whereas a heavy helicopter may carry a load of more than 250 kg, for example.
(2) Description of Related Art
The technological background includes the following documents: DE 33 23 513, U.S. Pat. No. 4,750,691, U.S. Pat. No. 5,020,742, DE 197 09 380, U.S. Pat. No. 3,088,608, GB 2 303 837, WO 2005/025984, and U.S. Pat. No. 4,013,270.
Document DE 33 23 513 describes an aircraft provided with a winch carried by one end of a support, the support comprising an extendible beam fastened inside a cabin. The winch is situated vertically above the load that is to be carried, and thus on the same side as the load relative to an anteroposterior plane of symmetry of the aircraft.
Document U.S. Pat. No. 4,750,691 describes hoist means including a retractable beam that is hinged on a flank of an aircraft. In addition, that hoist means is provided with a winch arranged on a faired zone of said flank, vertically in register with the fastening of the beam to the flank.
A cable from said winch then extends along said beam and leaves the aircraft via an outlet end for connection to attachment means.
When the beam is deployed out from the cabin, the cable enables external loads to be supported. The winch is then situated substantially vertically above the load to be carried, and on the same side of the anteroposterior plane of symmetry of the aircraft as said load.
Document U.S. Pat. No. 5,020,742 describes hoist means comprising a winch disposed on a flank of a helicopter and a beam for guiding the cable from said winch and serving to offset a hook of the cable away from the downwash of the lift rotor of the aircraft.
The winch and the load for carrying are both situated on the same side of the anteroposterior plane of symmetry of the aircraft.
Document DE 197 09 380 does not form part of the technical field of the invention since it relates to a building.
Document U.S. Pat. No. 3,088,608 provides for a pivoting beam, which beam is controlled by a motor situated vertically above the load carried by said beam, and thus on the same side of the anteroposterior plane of symmetry of the aircraft as said load.
Document GB 2 303 837 suggests using a winch co-operating with a deflector arm to space the winch cable away from the aircraft. The winch and the load carried by the winch are then both on the same side of the aircraft relative to an anteroposterior plane of symmetry of the aircraft.
Document WO 2005/025984 describes a lifesaving device rather than a hoist device, the lifesaving device having the function of snatching an individual while in flight.
That lifesaving device is fastened to the landing gear of an aircraft.
Document U.S. Pat. No. 4,013,270 describes a beam supporting a winch and a pulley.

Aircraft provided with hoist means, and an associated method


An apparatus and a method of coding/decoding an image are provided. The apparatus includes: a low resolution image coding unit that codes a low resolution image corresponding to an input image using motion estimation and compensation; and a residual image coding unit that performs intra mode coding with respect to a residual image which indicates a difference between a reconstructed image of the coded low resolution image and the input image by considering temporal correlation between neighboring residual images.

1. Field
The following description relates to image processing, and more particularly, to an apparatus and a method of coding power distribution using a residual image and an apparatus and a method of decoding power distribution.
2. Description of the Related Art
With the development of multimedia-related technologies, image compression techniques and image transmission techniques are being rapidly developed. Furthermore, popularization of portable multimedia devices such as digital cameras and portable terminals have greatly increased. In multimedia devices, it is required to code image data to a lower capacity of data information in order to more quickly and smoothly transmit the image data.
To satisfy the above-mentioned needs, image compression techniques such as a Motion Picture Expert Group 1 (MPEG 1) scheme, an MPEG 2 scheme, an MPEG 4 scheme, an H.264 scheme, and the like have been provided, and image communication via portable multimedia devices has been popularized through the image compression techniques.
Generally, a technique that can extend the time of usable power by compressing an image with low power is required since portable multimedia devices have limited battery capacity.

Method and apparatus of coding/decoding image


This invention relates to a low cost method of converting solid glass or ceramic microparticles into hollow microspheres by feeding them, along with pulverized coal, into coal-powered furnaces. Coal-powered furnaces generally produce microsized fused particles of the ash in the coal—called fly ash; and some of the fly ash particles may be hollow. By the present invention the yield of hollow microparticles is greatly increased by co-feeding, along with the pulverized coal, very small amounts of microparticles of inorganic materials known to have the ability to form hollow microspheres upon fusion.

Power plants that use pulverized coal as the combustible energy source produce, as a by-product, microsized fused particles of the ash contained in the coal. These particles generally take the form of glassy microspheres, and are called fly ash. The ash content of coals used for power generation generally varies from around one to ten percent of the weight of the coal. In some modern plants equipped to handle it, the ash content is even up to twenty percent. This ash generally is composed primarily of silica and alumina which average 50% to 60%, and 20% to 25%, respectively, of the weight of the ash. These two components are generally present in the coal, and make up the major portion of the ash. In addition to the alumina and silica, coal ash usually contains a significant amount of iron oxide, which is usually up to a few percent of the ash weight, but can range up to 10% or more. Minor amounts of many other oxides such as the oxides of titanium, calcium, magnesium and potassium, are usually present. These ash compositions are generally good glass formers.
Upon passing through the boiler furnace of a power plant the coal particles burn and the ash content of each particle fuses. This "fly ash" product is usually collected by electrostatic precipitators, and is sold in large tonnages for concrete highway construction, high rise building construction, and similar uses.
A small fraction of fly ash, usually around one percent of the ash produced, is in the form of hollow microspheres and will float on water. Those power plants which have settling water ponds are able to separate the floating fly ash from the denser fly ash, and recover it as a hollow glass microsphere product which is called "cenospheres." This product is generally about 0.7 to 0.8 grams per cubic centimeter in average particle density, and is therefore much more valuable than the denser fly ash. It is sold for use as a filler in light weight products such as plastics, putties, and concrete.
In contrast to the miniscule yield of cenospheres in fly ash the technology of commercial hollow glass microspheres has become advanced enough so that nearly 100% of the precursor feed particles fed into "bubble" formers will float on water. Hollow microspheres of this type are marketed by a number of companies, and a range of useful compositions for the microspheres has been taught in published literature. Blowing agents are incorporated into the glass so that, when heated above the fusion temperature of the glass, the gas is released to blow the particle into a bubble. These "bubbles" are produced with particle densities much lower than that of cenospheres, and usually average from around 0.4 down to around 0.1 grams per cubic centimeter. They therefore have a much higher market value than cenospheres, and sell for a higher price. These commercial bubbles are generally colorless, in contrast to the usual dark color of cenospheres.

Method of making hollow inorganic microspheres, and products made thereby


An oxygen concentrating apparatus including an output variable type compressor. Oxygen-concentrated gas may be supplied either continuously or synchronized with inhalation or timing of inhalations. In one aspect, when synchronous operation is selected, the compressor is operated at a lower output in comparison with continuous supply operation. In a second aspect, when synchronous operation is selected, the supply quantity of oxygen-concentration gas is set to zero during the exhalation period.

1. Field of the Invention
The present invention relates to an oxygen concentrating apparatus for supplying an oxygen-concentrated gas of high oxygen concentration to an inhaler.
2. Description of the Related Art
An example of a conventional oxygen concentrating apparatus, is described in JP-A-2002-85566 Gazette (Patent Document 1) of the present inventors. The oxygen concentrating apparatus described therein has a compressor for taking in and supplying compressed air, a concentration means for increasing the oxygen concentration of the compressed air to thereby obtain an oxygen-concentrated gas, a gas tank for storing the oxygen-concentrated gas obtained from the concentration means, a gas outlet for supplying the oxygen-concentrated gas stored in the gas tank to an inhaling person, a respiration detection means for distinguishing the respiration state of the inhaling person, a continuous supply control means for continuously discharging the oxygen-concentrated gas from the gas outlet, and a synchronous supply control means for supplying a set quantity of the oxygen-concentrated gas to the gas outlet synchronized with inhalation of the inhaling person. On the other hand, the synchronous supply control means reduces, during exhalation time, the supply quantity of oxygen-concentrated gas to the gas outlet and stores, during that time, the oxygen-concentrated gas in a gas tank to thereby prepare for the next inhalation. The apparatus is adapted so that, in response to a supply setting within a range of oxygen-concentrated gas that can continuously be supplied by the compressor and concentration means, the continuous supply control means is adjusted correspondingly. Furthermore, in response to a supply setting exceeding the range of oxygen-concentrated gas that can be continuously supplied by the compressor and the concentration means, the synchronous supply control means is adjusted correspondingly. When respiration synchronous operation by the synchronous supply control means is in effect, a surplus quantity of the oxygen-concentrated gas produced during the exhalation period is stored in the gas tank and, during inhalation the stored quantity is added to the gas that is supplied. Consequently, it is possible to meet the demands of a supply setting exceeding the range of gas that can be continuously supplied.
Because the oxygen concentrating apparatus mentioned above is set so that, in response to a supply setting within the range of oxygen-concentrated gas that can be continuously supplied, the continuous supply control means fixes the output of the compressor to a constant value, and in response to a supply setting exceeding the range of oxygen-concentrated gas that can be continuously supplied the synchronous supply control means is adjusted, a problem arises in that a constant amount of electric power is consumed irrespective of the quantity of the oxygen-concentrated gas that is required and thus the electricity burden cost is large.


An integrated EPROM device which can be manufactured using standard high-definition photolithographic techniques with unit cells of markedly reduced dimensions as compared to the minimum dimensions that can be achieved with the prior art, has field isolation structures between adjacent cells along rows of the array in the form of continuous isolation strips which extend for the whole column length of the array, thus avoiding the problems associated with photolithographic defining rectangular geometries. The electrical interconnection between the sources of the cells of each row is achieved by a special metal source "line" formed between two adjacent gate lines, using for the purpose a conformally deposited metal layer from which both the drain contacts and these source interconnection metal "lines" are created in a self-alignment way.

1. Field of the Invention
The present invention concerns an EPROM-type integrated device with metallic source connections and a process for the manufacture of EPROM cells of markedly reduced dimensions as compared to the minimum dimensions that can be obtained with conventional photolithographic definition techniques, by employing metallic source connections.
2. Description of the Prior Art
EPROM devices or memories are well known and widely used in modern digital technologies. These integrated semiconductor devices are characterized in that they have one or more arrays of EPROM memory unit cells, individually addressed and organized in rows and columns, each of which essentially comprises a floating-gate (or-double-gate) MOS transistor. The conventional architecture of these arrays of EPROM cells is also known, characterized by the presence of interconnection lines of drain contacts, belonging to transistors (cells) of the same column, perpendicular to gate lines. The sources of two cells (floating-gate MOS transistors) which are adjacent to each other in the direction of column alignment of the cells are electrically connected in common and, in a conventional array architecture, cells belonging to the same row have their sources electrically connected in common. In these devices the field isolation structures which separate the drains and gates of pairs .of transistors arranged in the same row have an essentially rectangular geometry (see FIG. 10), whether, they are embedded (e.g. of the BOX type) or formed by thermally growing a thick layer of field oxide. Usually drain contacts are formed by purposely masking and etching a dielectric layer uniformly deposited on the surface of the semiconductor wafer to insulate the transistor gate lines or structures.
As regards the possibility of photolithographic definition of ever smaller features, the above mentioned topographic aspects of the "traditional" architecture of these devices present the following problems.
Insulation Mask (or Active Areas Mask)
The geometries, even if perfectly rectangular on the mask, become chamfered on their reproduction on the wafer. This depends essentially on limits of an optical nature (diffraction) of the image transfer systems: the aerial image on the wafer of the figures projected by the mask is already rounded at the corners, a rounding which further increases in the subsequent development process.
With high-resolution optical equipment (e.g. with a N.A.>0.45) and with a high-contrast masking process, the phenomenon may be limited but still exists. Currently the best typical value that can be obtained is a chamfer with a radius of curvature of about a quarter of a micrometer. This value increases in the case of thermally grown field oxide.
Rounding of the corners of rectangular geometries leads to a critical state of alignment of the gate lines above and a certain dimensional variability of the channel width of the devices.
Contacts Mask
The photolithographic problems are the known ones of alignment in relation to the layers already formed and rounding (even more pronounced here) of the corners of the geometries with a consequent reduction of the actual drain contact area.

EPROM device with metallic source connections and fabrication thereof


A microchannel plate (MCP) apparatus and method in which the output metalization layer or electrode is covered with a thin coating to reduce the number of spurious electron emissions striking the phosphor screen or other collection anode in an image intensifier. Microchannel plates manufactured in this way have the beneficial effect of improving yield in the manufacture of night vision devices.

Wafer tubes typically comprise an image input window bonded to a photocathode, an MCP, to provide electron amplification, and, an imaging phosphor screen. These components are mounted in a vacuum envelope and electrically biased. The MCP is formed with input and output electrodes, which are conductive coatings on the input and output surfaces of the MCP. Traditionally, standard type MCPs do not receive further processing after deposition of electrodes on the input and output surfaces. Typically the electrodes are nichrome or inconel coatings in the case of standard units, and for feedback limited MCPs (FLMCPs) a thick coating of, for example, aluminum, is deposited on the output end of the MCP as more fully described in copending application Ser. No. 07/724,041 entitled Feedback Limited Microchannel Plate Apparatus and Method and filed in the names of Aebi and Costello, now U.S. Pat. No. 5,268,612 which issued on Dec. 7, 1993.
In general, in the manufacture of standard type night vision tubes, almost all meet specifications and do not include defects due to emission points on the output end of the MCP which disrupt and distort the output image. This type of distortion will be found only in about 4% of the typical manufacturing run. However, this problem is significant in the manufacture of enhanced tubes. Here losses as high as 50%, depending on the specification for the tubes being fabricated, may be typical. An enhanced tube, for example, may comprise a wafer tube in which the positioning of the MCP is closer to the output phosphor than would be the case for a standard tube or a FLMCP.

Microchannel plate with coated output electrode to reduce spurious discharges


This patent describes technology for generating ammonia from urea. The method is based on the hydrolysis of an aqueous solution of urea and/or biuret by heating under pressure to form a mixture of ammonia, carbon dioxide and water. The gas mixtures produced are useful for supplying ammonia at controlled pressure and rate of flow for many industrial applications without the risks and hazards associated with the transportation and on-site storage of ammonia, thereby providing a significant safety advantage over present industrial practice.

The present invention relates to the generation of ammonia from urea and/or mixtures also containing biuret in which an aqueous solution of urea is heated under pressure in a reactor from which a gaseous mixture of ammonia, carbon dioxide and water is withdrawn at a controlled pressure and at a controlled rate of flow.
Ammonia is a highly volatile noxious material with adverse physiological effects, which becomes intolerable at very low concentrations and presents substantial environmental and operating hazards and risk. It is classified as a hazardous material and many precautions are required in transporting and handling it safely. Urea, on the other hand, is a stable, non-volatile, environmentally benign material that is safely transported, stored and handled without such risk and, accordingly, can serve as a safe source of ammonia. The processes of this invention minimize the risks and hazards associated with the transport, storage and use of anhydrous and aqueous ammonia.
Many industrial plants require the supply of large quantities of ammonia, which frequently must be transported through and stored in populated areas. Important users among these are industrial furnaces, incinerators and the electric power generation industry. All of these are faced with a lowering of the amount of nitrogen oxides being discharged to the atmosphere in the combustion gases being emitted from their operations, as required by environmental regulations. Another important use is for the so-called xe2x80x9cconditioningxe2x80x9d of flue gas by which an improved collection and removal of particulate matter (fly ash) is obtained.
One of the important methods for removing nitrogen oxides derived from the burning of fossil fuels embodies their conversion to inert nitrogen gas by reaction with amine-type reductant materials, by processes such as Selective Catalytic Reduction (SCR) or Selective Non-Catalytic Reduction (SNCR). Two main reductant materials have achieved commercial acceptance for this purpose, namely, ammonia and urea. Ammonia is superior to urea as such for SNCR in several important aspects for this application and is required for SCR applications but, as previously related, ammonia presents substantial environmental and operating hazards and risk because of its high volatility and noxious nature. Numerous accidents that have resulted in deaths have occurred in the transport and handling of ammonia and local authorities have placed restrictions on its use in many locations. Urea, on the other hand, is a stable, non-volatile, environmentally benign material that is safely transported, stored and handled without such risk.
This invention is particularly useful for supplying ammonia for the SCR and SNCR processes for removal of nitrogen oxide from combustion gases, the conditioning of flue gas for improving the removal of particulate matter, and other applications in which ammonia is used, by which the environmental hazards of transporting and storing anhydrous and aqueous ammonia solutions may be avoided.
In the SNCR method, ammonia, urea or amine-type materials are injected into the hot flue gas stream, usually in-furnace while in a temperature range of 2000xc2x0 F.-1800xc2x0 F. In the SCR method, ammonia is the only reductant used, and the reaction is carried out at a lower temperature level, typically 750xc2x0 F.-600xc2x0 F., the specific temperature level being controlled by the catalyst system used.
The chemical reaction taking place in the flue gas by which NO and NO2 are removed is shown below for ammonia and urea:
Ammonia
4NO+4NH3+O2xe2x86x924N2+6H2Oxe2x80x83xe2x80x83[1]
2NO2+4NH3+O2xe2x86x923N2+6H2Oxe2x80x83xe2x80x83[2]
Urea
4NO+2CO(NH2)2+O2xe2x86x924N2+4H2O+2CO2xe2x80x83xe2x80x83[3]
2NO2+2CO(NH2)2+O2xe2x86x923N24N2O+2CO2xe2x80x83xe2x80x83[4]
Compared to urea, ammonia is more reactive, is more easily dispersed uniformly into the flue gas stream and is active over a broader temperature range, as well as being more effective in efficiency. Urea, as such, while also an effective reductant, forms unwanted byproducts, such as carbon monoxide (CO) and nitrous oxide (N2O), both of which are now under critical scrutiny by environmental authorities.
In the application of ammonia for the xe2x80x9cconditioningxe2x80x9d of flue gas, ammonia forms ammonium bisulfate with the sulfur oxides also present in the flue gas. These deposit and collect on the fine particles to form larger sticky agglomerates of the fly ash particles which makes their removal easier and more effective by both electrostatic collectors and fabric filters.
In this invention urea is converted to ammonia at the site where the combustion gases are being produced and there is no need to transport and store anhydrous ammonia or its aqueous solutions. Urea is the material that is shipped, stored and safely handled. The concept of this invention is also applicable to many other industrial uses of ammonia, such as pH adjustment, minimization of corrosion problems, heat treating of metal, etc.
The basic chemistry employed in the invention is a reverse of that employed in the industrial production of urea from ammonia and carbon dioxide and employs two reaction steps, as follows:
The first reaction in which urea hydrolyzes to form ammonium carbamate is mildly exothermic, while the second, in which ammonia and carbon dioxide are produced is strongly endothermic, with the result that the reaction to release ammonia and carbon dioxide requires heat and quickly stops when the supply of heat is withdrawn. Excess water promotes the hydrolysis reaction, the overall reaction for which is as follows:
xH2O+NH2CONH2xe2x86x922NH3+CO2+xxe2x88x921H2Oxe2x80x83xe2x80x83[7]
In the thermal hydrolysis process of the invention, the liberation of ammonia commences at around 110xc2x0 C. and becomes rapid at around 150xc2x0 C. to 160xc2x0 C., with or without catalytic assistance.
The generation of ammonia from urea is uniquely applicable to the control of nitrogen oxide emissions and the xe2x80x9cconditioningxe2x80x9d of combustion gas streams. The products of the hydrolysis are not foreign to those in combustion gas. The composition of combustion gas streams will typically have H2O concentrations ranging from 7% to 13% and CO2 concentrations arranging from 6% to 14% with NO concentrations ranging from 20 ppm up to 2000 ppm. Hydrolysis of a 30% urea solution produces an off gas with a composition of 20.5% NH3, 10.2% CO2 and 69.3% H2O (Molar). Ammonia for both SCR and SNCR systems for NO control is injected at NH3:NO ratios ranging from 0.5 to 2.0. With urea hydrolysis produced ammonia, the same NH3:NO ratios are required and the accompanying CO2 and H2O will add only a small amount of additional material compared to what is already present in the combustion gas stream, since NO concentrations in flue gas are on the order of 100 times less than their CO2 and H2O content. The CO2 and H2O added in the urea hydrolysis products will have no impact on the operation of the combustion process. There is also no major impact on the NO control system. Typically, ammonia is diluted with air, recycled flue gas, or steam prior to injection to insure a larger gas flow so as to provide a uniform distribution of the ammonia being fed to the flue gas for reaction with the nitrogen oxides. There must be a close stoichiometric matching and intimate mixing and molecular contact of the introduced ammonia with all of the nitrogen oxide molecules within a very short time. Otherwise, there will be either a discharge of unreacted ammonia and/or unreacted oxides of nitrogen in the off-gas. The treatment stream is typically introduced by distribution grids covering the entire cross-sectional flow area or by high velocity injection nozzles.
The prior art relating to the hydrolysis of urea has been mainly concerned with two areas of application: (1) a reduction in the amount of urea remaining in the low concentration waste streams produced in urea manufacture by its conversion back to ammonia and carbon dioxide under low pressure, which are then recovered and dehydrated and recycled back to the urea synthesis step, or (2) for the removal of nitrogen oxides from combustion gas streams by reaction with urea hydrolysates which are produced by a partial hydrolysis under high pressure of a urea solution, during which the ammonia formed is not released as generated and is held in solution while the urea is being heated and partially reacted.
The first of these, in which the urea in the dilute waste water streams discharged by urea manufacturing plants is converted to ammonia and carbon dioxide for recycle has been disclosed by Mavrovic in U.S. Pat. No. 3,826,815, Van Moorsel in U.S. Pat. No. 3,922,222 and Schell, in U.S. Pat. Nos. 4,087,513 and 4,168,299 None disclose the use of urea, as a source of ammonia for other uses, nor as a means of avoiding the hazardous aspects involved in the shipping and employment of ammonia in other industrial operations. In particular, there is no visualization of feeding a solution of urea to a reactor to produce a gaseous stream of ammonia, carbon dioxide and water which is generated at a controlled rate for use for other purposes than urea manufacture. No disclosure was made as to the incorporation of a urea hydrolysis step for producing ammonia for use in removing oxides of nitrogen by SNCR (Selective Non-Catalytic Reduction) or SCR (Selective Catalytic Reduction) processes from waste combustion gas streams, the xe2x80x9cconditioningxe2x80x9d of flue gas to improve particulate collection, or for other applications in which ammonia is employed. All of these recovery processes involve stripping and distillation devices for removal and concentration of the ammonia formed.
In the second group, von Harpe et. al. in U.S. Pat. No. 5,240,688, disclose a system and operating conditions for the partial hydrolytic decomposition of urea to produce ammonium salts and unreacted urea, all in solution form, that are useful for the reduction of nitrogen oxides in combustion gas streams, but not as a gaseous ammonia-containing product that is free of unreacted urea and ammonium carbamate.
The von Harpe patent is specifically directed to conditions for the SNCR (Selective Non Catalytic Reduction) process for NOx control. Operating conditions are selected such that hydrolysis products formed will be emitted from the system as ammonium salts, either by operating at pressures in excess of 1,200 pounds per square inch or by cooling the hydrolysis products to below 70xc2x0 F. There is no suggestion about operating at the lower pressure levels of the present invention in which ammonia and carbon dioxide are emitted in gaseous form and which are also useable by SCR (Selective Catalytic Reduction) process systems and other processes needing ammonia gas.
The process of this invention where an aqueous solution of urea is continuously fed into a heated reactor and a continuous stream of gaseous ammonia, carbon dioxide and water produced and discharged without any urea or ammonium salts for use by both SCR and SNCR nitrogen oxides reduction processes, or for other uses of ammonia, is not disclosed by von Harpe.
Lyon in U.S. Pat. No. 3,900,554 describes a process in which ammonia is used to reduce nitrogen oxide concentrations in combustion exhaust gas streams for use with the so called SNCR (Selective Non-Catalytic Reduction) method. In U.S. Pat. No. 4,220,632, Pence, et. al. describes a process in which ammonia is used to reduce nitrogen oxides in combustion exhaust gas in the presence of a catalyst by the SCR (Selective Catalytic Reduction) process.
Jones, in U.S. Pat. No. 5,281,403, describes a method for removing nitrogen oxides from a combustion gas stream in which a solution of urea is partially hydrolyzed by passage of a urea solution in an injection lance which is heated directly by the hot combustion gas stream containing the nitrogen oxides into which the lance is inserted, while keeping the urea hydrolysis products in the liquid phase in the presence of a conversion catalyst, and then injecting the partially converted urea solution from the lance system into the combustion gas. The Jones patent is directed to the higher temperature (1800-2000xc2x0 F.) SNCR process and does not produce a gaseous ammonia-containing product stream free of unreacted urea that can be used directly in both the SNCR and the lower temperature SCR processes, as by the present invention. Jones teaches that high pressures of greater than 900 psig are required to keep the ammonia formed in the hydrolysis reaction in solution and that conversions of greater than 90% may be obtainable, whereas the present invention operates effectively at much lower pressures, of only 20 to 500 psig, and preferably at 60 to 150 psig. Ammonia and carbon dioxide are readily released in gaseous form from the liquid media under these conditions with urea and biuret conversions reaching 100%. The systems of Jones and others do not consider the presence or hydrolysis of biuret, which is present in essentially all regular commercial grades of urea, nor provide for a controllable continuous supply of gaseous ammonia and carbon dioxide for feeding to a nitrogen oxides emissions control useable by the SCR method, nor for other industrial uses requiring ammonia.
Jones also describes in his FIG. 4 a loop system for generating ammonia vapor in which the urea containing solution is hydrolyzed under high pressure conditions in order to keep the ammonia formed in solution in the catalyst chamber, until the pressure is subsequently released by flashing to a lower pressure through a pressure relief value, but with no control of the gas pressure or gas flow. Such a system does not provide a suitable means for controlling the ammonia flow to meet the demanding control requirements of NOx control systems and other process requiring that the supply of ammonia be at a rate which essentially matches the up-take rate of the NOx or other component being reacted, nor show or teach the necessity of keeping the ammonia and carbon dioxide product vapor mixture heated for feeding to the NOx control system. The loop system described by Jones utilizes a two step system for heating and reacting, comprised of an initial heat exchanger and a following conversion catalyst chamber, both of which are under high pressure. This means that the substantial amount of heat required for carrying out the endothermic hydrolysis reaction to release ammonia must be contained in the circulating liquid stream as sensible heat prior to being brought into the catalyst reaction chamber where the endothermic reaction heat is required for the hydrolysis to proceed. Accordingly, a very large amount of liquid must be pumped up to the high operating pressure specified and the need to heat the solution to a substantially higher temperature than with the present invention, which supplies the heat required at a lower temperature directly where the endothermic reaction is occurring and does not suffer the high pumping cost for recompressing the circulating liquid, thereby avoiding both of these problems and the high costs involved for so doing.
Another consideration with the process of Jones is the matter of his catalysts, their life and the manner of their use. All of the catalyst salts or oxides indicated will tend to be decomposed or solubilized by continuous contact with hot ammonia containing liquid streams. Ammonia is a powerful solvent, particularly at high pressures and temperatures around or above its critical temperature. The actual chemical composition of the catalysts employed is not identified or specified, other than by an elemental name. Salts of vanadium, chromium and molybdenum are classified as toxic and their discharge into flue gas streams would be severely restrained from an environmental viewpoint. In their metallic form, these elements were not found to show significant catalytic activity.
Young in U.S. Pat. No. 5,252,308 describes a two-step acidic chemical process for converting urea to produce ammonia that employs polytropic acids, such as H3PO4. The safety advantages of on-site ammonia generation are pointed out and that ammonia generated by this method can be used for the removal of nitrogen oxides from combustion gas. His two-step acid process, however, is substantially more complicated in its equipment requirements and method of operation, and is not readily adapted to meet the critical rate of ammonia generation required. The ammonia is contacted with the combustion gases at a pressure and rate consistent only with the reaction rate at the reaction temperature. The pressure during ammonia evolution is not controlled or maintained at any set elevated level. The application of the process to the removal of nitrogen oxides by the SCR type process, or for the xe2x80x9cconditioningxe2x80x9d of flue gas to give improved removal of fine particulate matter, is not disclosed.
Miller and Laudal in U.S. Pat. No. 5,034,030 describe a process for flue gas conditioning applied to fabric filtration in which ammonia gas and sulfur trioxide are injected for improved performance of a fabric filter. Ammonia gas and sulfur trioxide have also been used for conditioning of electrostatic precipitators as discussed in U.S. Pat. No. 4,533,364, Altman, et. al. Dismukes also describes the conditioning of fly ash with ammonia. Lookman, et. al. in U.S. Pat. No. 5,567,226 discuss the controlled injection of ammonia for improving the performance of particulate control devices.
The method of removing nitrogen oxides from combustion gas streams by SNCR (Selective Non-Catalytic Reduction) and SCR (Selective Catalytic Reduction) processes, the improvement which comprises heating an aqueous solution of urea, or mixtures of urea containing biuret, or ammonium carbamate on site, to produce a gaseous ammonia-containing product under controlled pressure and rate of flow, said gaseous ammonia-containing product being essentially free of urea, biuret, or ammonium carbamate, and contacting said ammonia-containing product with the nitrogen oxides in said combustion gas streams.
A preferred method of this invention includes producing a gaseous ammonia-containing product from urea, or mixtures of urea containing biuret, or ammonium carbamate, said ammonia-containing product being essentially free of urea, biuret, or ammonium carbamate, the process comprising;
a) Feeding an aqueous solution of urea, and/or mixtures containing biuret, in a concentration range of about 1% to about 76% solids, to a reactor in which it is heated to a temperature of at least about 110xc2x0 C. but less than about 200xc2x0 C. and operated at a pressure of at least about 20 PSIG but less than about 500 PSIG, and therein hydrolyzing the urea and biuret to produce a gaseous product stream of ammonia, carbon dioxide and water:
b) Separating the gaseous ammonia and carbon dioxide formed from the liquid aqueous reaction media at the operating pressure;
c) Retaining the liquid phase reaction media in the reactor for further conversion of unreacted urea, biuret and intermediate ammonium carbamate to gaseous ammonia and carbon dioxide, and/or recycling a portion of the reaction media back into the reactor or feed solution to the reactor for further conversion; and
d) Withdrawing the gaseous ammonia and carbon dioxide-containing product stream separated in Step b) at a controlled pressure and controlled rate of flow for external use.
In another aspect, the invention is applicable to the removal of fly ash from combustion gas streams. This aspect includes the method in which sulfur oxides and ammonia are added to combustion gas streams to obtain better removals of fine particulate matter by baghouses or electrostatic precipitators, the improvement comprising producing the ammonia under controlled pressure and rate of flow from urea, biuret, or ammonium carbamate, and mixtures thereof, as a gaseous mixture of ammonia and carbon dioxide, and contacting said ammonia with sulfur oxides and particulate matter in said combustion gas stream.
The present invention relates to the generation of gaseous ammonia from urea and/or mixtures containing biuret. The process involves the hydrolysis of an aqueous urea-containing solution that is heated under pressure in a reactor from which a gaseous product mixture of ammonia, carbon dioxide and water is withdrawn. The method minimizes the risks and hazards associated with the transport, storage and transfer of anhydrous or aqueous ammonia solutions by virtue of their production from urea at the point of use.
The process of the present invention, in its preferred form, injects an aqueous solution of urea having a concentration of about 10% to about 50% by weight of urea into a hydrolysis reactor. The hydrolysis reactor is typically operated at temperatures of about 125xc2x0 C. to about 180xc2x0 C. and gas pressures from about 20 psig to about 200 psig with a liquid residence time such that the off-gas product comprising ammonia, carbon dioxide and water vapor is withdrawn as a gas at a controlled pressure and controlled rate of flow, said off-gas being maintained above about 60xc2x0 C. In its overall context, feed concentrations of about 1% to about 77% urea may be used, with temperatures between about 110xc2x0 to about 300xc2x0 C. and operating pressures of about 30 psig to about 500 psig. The temperature and gas pressure are controlled by the input of heat to the reactor.
In a typical system the heat input is controlled to maintain a constant pressure in the reactor and temperature is a dependent variable. As gas is withdrawn, the pressure would drop but for the addition of heat at a rate which is required to maintain the pressure at a constant level.
In general, a controlled rate of flow of ammonia being produced refers to a generally constant or steady rate of ammonia production. As used herein, it also refers to the contacting of a combustion gas stream containing NOx, sulfur oxides or fly ash which is approximately equated or balanced to the demands of the combustion gas stream, that is, the ammonia produced is sufficient to react with the component or components in the gas stream being removed, or reacted with.
A precaution that must be observed in the use of urea hydrolysis products is that the product gas stream must be maintained at a temperature above about 60xc2x0 C. in order to avoid the deposition of solid ammonium salts which form at lower temperaturesxe2x80x94salts such as ammonium carbonate and ammonium bicarbonate. These deposits are readily decomposed and re-vaporized by heating the distribution system to above about 60xc2x0 C.
The pressure may be measured on either the liquid side or gas phase side of the reactor. When measured on the gas side the pressure gauge is heated to above 60xc2x0 C. to prevent the deposition of solids in the gauge. On the liquid side the pressure gauge can operate at ambient temperature or at temperatures up to the temperature of the solution. Emergency pressure relief can be on either the gas side or the liquid side of the reactor. In both cases the vent can be connected to a water containing dump tank to trap ammonia gas and prevent its release to the atmosphere. Dumping hot reactor solution into a quantity of water (temperature less than 40xc2x0 C.) equal to or greater than the solution in the reactor stops the hydrolysis process and prevents the further generation of ammonia. A pressure release value on the gas phase side is heated to above about 60xc2x0 C. to insure that solids do not build up in the value.
The rate of the hydrolysis reaction may be enhanced over that of water alone by the addition of certain materials to the aqueous reaction media. These include: (1) oxides and the ammonium and alkali metal salts of Groups III-B, IV, V and VI-A of the Periodic Chart Of The Elements, among which are vanadium oxide, ammonium vanadate, molybdenum oxide, ammonium molybdate, chromium oxide, ammonium chromate, ammonium borate, and other elements falling within these groups, (2) the hydroxides, carbonates and bicarbonates of Group I (e.g., KOH and NaOH) and (3) certain active surface solids, including activated carbon, silica or alumina, and ion-exchange resins in their acidic or basic forms. In this invention the enhancer materials remain in the reaction media and are not discharged. These higher rates, however, may also be obtained by a moderate increase in temperature and pressure with water alone.

Methods for the production of ammonia from urea and/or biuret, and uses for NOx and/or particulate matter removal


A flash memory device with auto-trimming functionality includes a memory cell array comprising first memory cells and a fuse sector, a read circuit for reading a memory state of the first memory cells, an offset circuit for outputting offset current values, and an auto-trimming circuit. The auto-trimming circuit has a register for storing a current characteristic, a current control module for modifying input current applied to a first memory cell under test at a first address according to the memory state, and updating the current characteristic to the modified input current, an address counter for starting application of the modified input current to a second memory cell at a second address for test when reading the first memory cell passes, and a programming circuit for programming the fuse sector according to the current characteristic and the offset current values.

1. Field of the Invention
The present invention relates to flash memory testing, and more particularly to a method of automatically setting trim codes for a flash memory and related device.
2. Description of the Prior Art
Flash memory devices are programmed, read, and erased by a relatively high voltage compared to a normal operating voltage. The high voltage is generated by a voltage regulator, which acts as a direct current to direct current (DC-DC) converter. Due to process variation of a semiconductor fabrication process for fabricating the voltage regulator, the high voltage may not be generated accurately, which would affect performance of the flash memory device. Thus, the flash memory device includes a fuse cell array for performing trimming on the high voltage generated by the voltage regulator.
The fuse cell array has at least two disadvantages. First, the fuse cell array can only be set one time, which reduces flexibility. Second, dies of the flash memory device must be tested one-at-a-time.

Method of setting trim codes for a flash memory and related device


A distributed hash tree-based authentication system for digital input records has more than one upper-level core node, each of which receives at least one uppermost value from aggregators. Communicating with each other about which aggregator values they have received, the nodes try to reach agreement as to which of these values should be included in duplicated current intra-node hash tree evaluations so as to form a consistent top-level value used as the basis for digital signatures associated with the digital input records.

The ability to verify the authenticity of digital data in the electronic age has become more challenging at the same time as it has become more needed. Documents (defined broadly as any body of digitized information) in electronic form are everywhere in modern banking, commerce, government, law, indeed, in modern life in general. In a world where documents are created, submitted, processed, stored, considered, etc., all electronically, sometimes even in multiple locations in the "cloud" unknown to the users themselves, notary or other official seals, physical signatures, special papers and other such tools are becoming increasingly unsuitable and unreliable.
Perhaps the most common way at present to verify the authenticity of electronic documents is to use some form of digital certificate to "sign" them, which is typically accomplished using some form of asymmetric cryptography. Public key cryptography is fast enough to enable almost instantaneous certificate generation. However, there is an inherent weakness in using asymmetric cryptography to create digital signatures: Cryptographic signature keys may become compromised. Once a key has become compromised, the certificates created with that key are no longer verifiable. Since the likelihood that a key will become compromised increases over time, certificates created by using keyed cryptography are useful only for a short term.
Key-based systems suffer from other disadvantages as well. For one thing, it becomes necessary to keep track of sometimes very large sets of keys and whether they are still valid.
Many common systems treat each digital record as a free-standing entity unrelated to any other—keys are generated for each record, and security depends on that key set. Nothing that happens to any other record, or at any other time, will reflect in information associated with a given record. Entire systems can therefore be compromised without an individual user being aware of it.
Some other systems increase verifiability by creating a data structure in which information from more than one record at a time is used to compute a composite, higher-level value that can be used to help detect unauthorized changes to any of the records. For example, a tree structure of hash values (for example, a Merkle tree structure) of digital input records can create a single, highest level verification value such that even the smallest change to one input record will yield a different highest-level value upon recomputation and reveal that a change has occurred.
When it comes to verifying the authenticity of digital documents, regardless of whether the user cares about proof of receipt order or not, most existing methods have the serious flaw that users must in some way trust some service provider at some point. In other words, even with a theoretically trustworthy verification scheme, one must then instead trust the entity that performs the verification. Trust in such systems is sometimes unwarranted, but is always a reason at least for concern. In 2007, for example, it was observed that the BSAFE cryptographic library of RSA Security (a major provider of cryptographic technologies) used as a default the DUAL_EC_DRBG random number generator, which included a "back door" that resulted from use of a set of initiating numbers supplied to RSA by the U.S. National Security Agency. Even with the best keys, therefore, one must still wonder about the trustworthiness of the keymaker.
One alternative to total reliance on keys includes publishing a digital record along with some verifying information. This may avoid the need for such trust, but a pure publication-verification scheme is unsuitable for large collections of documents that each may need authentication. In other words, one or both of two common problems beset known authentication schemes: either there must be some "trust authority" or the systems are not amenable to extensive scalability.
Guardtime AS of Tallinn, Estonia, provides a distributed, hash tree-based data-verification system that does not rely on keys at all, is highly scalable, and that, in the most developed embodiment, avoids the need for trust even in the Guardtime system itself—verification of a given data set may be carried out independently, relying only on mathematical procedures open to all.
FIGS. 1-5 illustrate the general infrastructure of the distributed hash tree infrastructure used to validate data in a system such as the one provided by Guardtime, including an embodiment that includes publication for second, higher-level verification. Sets of digital data ("documents" or "digital records") are input by a set of lowest-level systems that comprise clients 2000. The digital data is transformed using a hash function, which provides a hash output value. This client-level hash output value forms a low-level node in a global hash tree and is, accordingly, then hashed in successively higher levels with other nodes in gateways 3000, which in turn hash their various nodes in respective internal hash tree structures to form inputs to aggregators 4000. The aggregators in turn hash their input nodes in a tree structure to form highest level aggregator hash values, which are submitted as inputs to input nodes of a hash tree structure in a core system 5000, which in turn hashes at least the current set of input node values together to form a root hash value that forms a current value ti in a calendar 6000. For each client-level input data set, a unique digital signature is returned that encodes, among other optional data, the hash values of "sibling nodes" in the global hash tree, as well as the corresponding calendar value, such that, given the data set and the signature, one can recompute one's way upward through the global hash tree. If the resulting uppermost computation matches the calendar value, there is an exceptionally high level of certainty that the data set is identical to the one that led to the digital signature.
The operation of the system shown in FIGS. 1-5 is described in greater detail below, but is summarized here so as to illustrate a potential weakness: If the verification infrastructure is implemented such that a single core 5000 processes all requests for signatures, then this core represents a single point of failure with respect to the entire signature and verification infrastructure. In other words, if, for some reason, for example, the server that forms the core, or the network connection to the core, were to fail, then no clients would be able to digitally sign input records. At a lower level, if one of the aggregators were to fail, or its network connection to the core were to fail or become too slow, then no client whose requests feed to that aggregator would be able to get digital signatures at all, or within a current period. What is needed is therefore a way to overcome the concern about single-point-of-failure, while still providing well-determined data signatures that can be used for later data validation.

Redundant fail-safe synchronization in a data authentication infrastructure


A system for mounting armor to a structure such as a vehicle hull has a base for attachment to the structure, an adapter engaged with the base and with the armor for coupling the base to the armor, and a fastener, for example a pin or a bolt) for rigidly securing the adapter with the base. The system advantageously permits retrofitting of previously unarmored structures and/or permits replacement of damaged or obsolete armor. A kit for retrofitting a structure with armor has a base for attachment to the structure, an adapter for engagement with the base and with the armor for coupling the base to the armor, a fastener for rigidly engaging the adapter with the base, and instructions for mounting the armor on the structure using the base, the adapter and the fastener.

Structures, in particular vehicles, may be provided with ballistic protection by armor. Armored vehicles may be originally manufactured with armor protection integrated into the structure, however, the need to replace the armor due to damage or differing operational requirements of the vehicle is made difficult by such integrated armor. Furthermore, it is often desirable to retrofit previously unarmored vehicles with armor. It is therefore desirable in the art to provide a system for mounting armor on a structure, for example a vehicle, which permits easy replacement of armor and which permits retrofitting of previously unarmored vehicles.
There are a variety of kinds of armor that may be used to protect structures such as vehicles, for example, composite armor and spaced metallic armor. It is desirable to have a mounting system that has the versatility to mount more than one kind of armor on a structure.
Thus, there is a need in the art for a versatile armor mounting system that permits replacement of armor on structures and/or permits retrofitting of previously unarmored structures.


An anti-ligative ergonomic type door-knob primarily of the institutional type, essentially serving to defeat the effort of a temporarily mentally-depressed room occupant from succeeding in committing self-hanging via contrived ensnaring by which to secure a cord like hanging-noose. Generic-variant embodiments of my anti-ligative doorknob are set forth, including both a circular and semi-circular escutcheon-plate for I-shaped V-shaped Y-shaped X-shaped fin-levers, and also a non-finned hemispherical iteration. The novel critical minimum approximate 40-degree anti-ligative principle of my LIFESTAR™ doorknobs reliably prevents a person ensnaring any heretofore problematically hazardous to portion of the door-knob assembly, while my optionally cooperating door latchbolt is formed to a matching critical minimum approximate 40-degree anti-ligative tri-beveled latchbolt as well. Further suicide-deterrence is achieved by effectively submerging the doorknob into the door escutcheon-plate, thereby leaving virtually no declivity by which a suicidal-person can secure any manner of self-inflicted hanging-cord.

1. Field of Invention
This invention relates to rotary-actuators in the form of door-knobs, and more specifically it relates to door-knobs and associated latches for hinged-doors employing anti-ligative ensnaring resistant means, hence particularly suited to institutional usage (ie: psychiatric-institutions, hospitals, jails, etc.)—as an impulsive-suicide deterrent.
2. Relevant Prior-Art
Presently there are several door-lock companies producing what they elude to as anti-ligative suicide deterrent door-knobs, nevertheless successful attempts continue to be achieved via these hardware owing there for one reason or another still not achieving true non-ensnarable construction. For example, some firms produce door-knobs which while perhaps designed free of ensnarable declivities, such as eliminating the traditional bulbuls grasping-knob, —yet employ to shallow a pitch or slope of the door-knob, —thereby unwittingly enabling a person to snag a loop of cord there around, and ultimately obtain some manner of cross-lashing to the opposite like designed door-knob for example. Still other manufacturers make L-shaped door-knobs claimed to be anti-ligative, which are nevertheless predictably ensnarable no matter how slick their design, —merely by means of crosslashing. However, I have discovered and make full disclosure herein, of a critical transition-point technique of construction to which no cording can be successfully secured; —this vitally critical slope or pitch angle being an approximate minimum of 40-degrees (—as measured relative to the door-knob's central-axis of rotation).
Background research discovery provided relatively little prior patent-art regarded as germane to this disclosure, chronologically for example U.S. Pat. No. 3,792,877 (filed: June 1972) shows a latch-bolt member (102) of cylindrical design, which poses a typical problem with regard to the nature of its horizontal slide-surface providing a potential ensnaring point where a small cord such as a shoelace or electrical-cord could be lodged in an ensnaring manner by a mentally-depressed person impulsively intent upon terminating themself via a contrived hanging-noose means.
In pending U.S. Pat. No. 0,135,956 (filed: March 2003) is shown an ergonomic ErgoHandle', which exhibits a novel snare preventative configuration, —however it is entirely remiss of any positive-acting latching and release means; —therefore as such, it is essentially limited for usage in conjunction with cabinet-doors and drawers and the like.
In U.S. Pat. No. 0,220,398 (filed: March 2006) shows an doorknob which in its FIGS. 1 & 2 embodiment is substantially free of surface undulations such as a reduced neck-diameter which would enable a person to snag a cord like entity such as a shoelace; —however, the joint-crevice created where the doorknob (1) merges with the decorative-ring (2), along with the overall shape of the doorknob projecting at a right-angle from the door-surface, in of itself constitutes a convenient ensnarable protrusion. Accordingly, while ergonomic in design relative to the inventor's desire to provide a doorknob offering improved rotational grasping ability, the substantially cylindrical shape still poses the inherent problem of ensnarability residing in all conventional doorknobs.
Additionally, there is a less germane class of utility-knobs such as have been designed for gas-burner valve-controls for kitchen-stoves, and radio control-knobs, such as are generally exemplified in U.S. Pat. No. D114,315 (filed: October 19328) showing a 3-finned knob, No. D145,210 (filed: November 1943) showing a 4-finned knob, and No. 267,194 (filed: December 1982) showing a 6-finned; —however, none of the designs anticipated an anti-ligative purpose, whilst all of the designs employed shapes which characterized exactly the problem which my invention serves to overcome, whereby each of them would allow a cord to be lodged transversely across their finger-hold fins without sliding off; —while also posing the potential to secure a cord of some sort behind the base of the knob.
Therefore, in full consideration of the preceding patent review, there is revealed a need for an improved form of hardware to which these identified prior-art inventions have been at least remotely addressed. The inventor hereof believes their newly improved door-knob device, referred commercially to as the LIFESTAR™ doorknob, being developed for production under auspices of—Shilts-Mfg./Mkt. Co., exhibits certain unique human-factors design advantages, as shall become clearly revealed in the subsequent portion of this disclosure.

Anti-ligative doorknob with tri-beveled latchbolt


An assembly for a wire shelf is disclosed including a novel cantilever bracket for mounting to a vertical wall support bracket. The cantilever bracket includes an inner nesting receptacle and one or more relatively positioned grooves that preclude the wire shelf from pivoting outward when excess weight is placed on the outer or front portion of the shelf. The cantilever bracket maintains the wire shelf in a safe position by restraining the inner portion of the shelf and preventing the upward pivotal movement thereof.

A safety problem exists when ventilated or wire-type shelves are used with standard vertical wall supports designed for home or office use. The wire shelves are not adequately anchored down by brackets designed for use with vertical wall supports; the wire shelves have a tendency to flip outward spilling the contents of the shelf and possibly causing injury.
Wire shelving systems are well known and are becoming increasingly popular. In the past, wire, or ventilated, shelves have been limited to industrial or commercial use such as in large refrigeration units, stock rooms and warehouses. The advantage of wire shelves is that they allow circulating air to reach the goods stacked on the shelves. The wire shelves designed for industrial or commercial applications are heavy-duty, free-standing structures or they may be securely bolted or attached to a wall. However, wire shelving units are not limited to industry use and are increasingly used in homes, not only for the ventilation advantages, but for aesthetic purposes as well.
There is an need for the development of a wire shelf unit compatible with standard vertical wall supports which have a column of slots for height adjustment. In these systems, two or more cantilever brackets provide support for a shelf. The brackets engage one or more slots in a vertical wall support. Because a series of slots extend from the top to the bottom of the vertical wall supports, the cantilever support brackets, and therefore the shelf itself, are height adjustable.
The aforenoted problem exists when standard cantilever support brackets are used in combination with wire shelves. If an excess amount of force or weight is applied to the front of the wire shelf, the shelf has a strong tendency to flip outward in a pivotal motion about the front edge of the shelf thereby spilling the contents of the shelf and possibly the shelf itself on the floor.
The possibility of wire shelves pivoting outward poses serious safety concerns. For one, it is common to use these shelves to store fairly heavy articles. Therefore, these heavy articles have the potential to cause serious injury to a consumer. Further, valuable items or fragile items such as glass may be stored on the shelves and may be destroyed if tipped forward onto the floor.
Therefore, an improved wire shelving system is needed to adequately secure the rear edge of the wire shelf to the bracket. While various methods for securing wire shelves to brackets are known, the known designs are fairly complicated to assemble and are therefore not ideal for home use. No known design combines the safety required with the ease of assembly demanded by modern consumers.


A power operated string vibrating device for selectively vibrating a string of a stringed musical instrument having at least one string. The string vibrating device comprises a support member positioned on the musical instrument proximate a string. A first pulley is rotatably mounted on the support member on a first side of a string for receiving a cable. The first pulley has one of the strings associated therewith. A second pulley is rotatably mounted on the support member on a second side of the string for receiving the cable. The second pulley is movable between a first position and a second position. A spring biases the second pulley towards the first position. An endless cable is drivingly interconnected to the pulleys such that when the second pulley is in the first position the cable does not contact the string, and when the second pulley is in the second position the cable contacts the string. An electric motor is mounted on the support member for driving the cable at a predetermined speed. A finger engageable button is mounted on the support member for selectively moving the second pulley to the second position, whereby when the second pulley is in the first position, the string does not produce sound and when the second pulley is in the second position, the string is vibrated by the cable and thereby produces sound.

The present day musical, stringed instrument, such as a guitar, includes a hollow body having a neck extending therefrom, with laterally spaced tensioned strings being supported in longitudinally extending positions thereon and in pressure contact with a tail piece. Guitars have fretted necks to serve as a fingerboard. Vibrations of the strings are transmitted from the tail piece to the top of the body. The top is coupled to the bottom of the body by a post. The top has an opening therein. The top and bottom, the opening, and the hollow interior of the body form a multi-resonant system for coupling the vibrating strings to the air to produce musical tones.
In an electric guitar, the vibrations of the strings are transmitted to a bridge, which bridge, in turn, transmits the vibrations to a mechano-electric transducer. The transducer converts the mechanical vibrations into corresponding electrical vibrations. These vibrations are amplified by suitable electrical means to energize a loudspeaker to produce musical tones.
In both the conventional guitar and the electrical version thereof, the strings are plucked by the fingers or with a pick to cause the strings to vibrate. However, the vibrations of the plucked strings quickly dampen out and the musical tones produced thereby is of short duration.
The present invention overcomes the above-described disadvantages by providing a manually actuated, power operated device that permits at least one moving member to be brought selectively into light pressure contact with a string of the musical stringed instrument to cause the former to vibrate. The string will vibrate so long as such pressure contact is effected, and, as a result, novel and unusual musical effects may be achieved from the stringed instrument, such as a conventional or electric guitar, that are not attainable when the strings are merely plucked.

Power operated string vibrating device for selectively vibrating a string of a stringed musical instrument


A head cooler (10) comprises a thermal exchange cap (11) and an outer insulating cover (12) to be arranged on a patient s head. The cap (11) has a channel system (31, 32) for a cooling fluid forming an inside heat exchange surface to be applied on said head for cooling the head. The thermal exchange cap (11, 60) is adjustable and/or adaptable to compensate for a discrepancy in shape and size between the inside surface of the head cooler (10) and the head. The head cooler (10) may further comprisean eyebrow cooler (140) for cooling the area of the eyebrows. The head cooler (140) is used in medicine. A method for preventing hair loss of a patient is provided by arranging the head cooler (10) on the head of said patient.

A human being undergoing treatment with cytostatics (chemotherapy) or similar treatment often suffers from loss of hair. By maintaining, during the treatment, a low temperature on/at/of the hairy region, usually the scalp, such a loss can be eliminated or substantially reduced.
A head cooler disclosed in U.S. Pat. No. 6,156,059 comprises a head cover to be placed over a human scalp for enclosing the patient's head and neck. Flow passages, through which a cooling fluid is flown, are provided in the cover which forms an inside heat exchange surface to be applied against the scalp for cooling the scalp. A temperature sensor is mounted in connection with each flow passage for registering the local temperature.
The size and shape of heads of different patients may vary a lot. If the head cooler is too large or too wide, a gap may be formed between the heat exchange surface and the head. Then, the cooling of the scalp may be jeopardized, since the heat exchange surface is not held in contact with the scalp over the entire surface thereof. As a consequence the cooling efficiency will be reduced in the area of the gap resulting in loss of hair.
It is proposed according to the Japanese Patent Abstract of U.S. Pat. No. 6,270,060 to mount to the inside surface of the head cover a plurality of bag bodies to which a pressure fluid is supplied in order to press a heat exchange surface against the patient's head and neck for cooling the scalp.
A drawback with currently used head coolers is that the head cover is not easily adaptable to the size and/or shape of the patient's head and neck, which may result in a too low or an impaired cooling efficiency.
Another disadvantage is that the currently presented head coolers do not involve the cooling of the eyebrows or the region of the eyebrows. Loss of the eyebrows is also considered to be a problem for patients undergoing treatments with cytostatics.


The invention relates to a combination of compounds for de-icing and/or anti-skid treatment, which combination comprises betaine and at least one other de-icing agent, which has been selected from the group consisting of acetates, formates, urea and combinations thereof. The invention also relates to a method of de-icing and/or anti-skid treatment, wherein a combination of compounds selected from the group consisting of acetates, formats, urea and combinations thereof, are applied to a slippery surface or a surface vulnerable to slipperiness. The invention further relates to the use of betaine for de-icing and/or anti-skid treatment, when betaine is used in combination with at least one ether de-icing agent, which has been selected from the group consisting of acetates, formates, urea and combinations thereof.

The prevention of ice-formation and slipperiness is extremely important at airports in order to maintain safe conditions for take-off and landing as well as for general aviation safety. The most important requirement for the anti-skid treatment at airports is ensuring aviation safety by maintaining sufficient friction on the asphalt surface of the runway. There is a certain friction requirement for runway paving, and this must be fulfilled whenever there is air traffic at the airport. The coefficient of friction is a constant that describes the interface between two solid substances, and it expresses the amount of friction present as the bodies slide against each other. The coefficient of friction is always more than zero and in practice always less than one. As far as the friction requirement at airports is concerned, the value must usually be at least 0.3, preferably 0.4.
Mechanical methods are primarily used for anti-skid treatment on runways. Chemical melting agents are required for removing the hoarfrost and ice formed on the runway surface, as well as for anticipatory anti-skid treatment. In general, ice-melting agents are used for the anti-skid treatment, optionally with added thickeners in order to increase viscosity, as well as water, surfactants and corrosion inhibitors. The purpose of the ice-melting and anti-skid agents is to disrupt and weaken the adhesion of the ice to the surface of pavement, after which the surface can more easily be mechanically cleaned.
For the prevention of slipperiness on roads, chlorides have mainly been used as ice-melting and anti-skid agents. The substances that are used in road maintenance, such as sodium chloride, could not be used at airports, since they rapidly rust and erode the metal parts of the planes as well as airport equipment. In addition, chlorides have a harmful effect on groundwater quality, soil, vegetation and soil microfauna. Traditionally, water-soluble organic compounds such as urea have been used for melting ice at airports. However, the use of urea has largely been given up, since it has been found to cause significant environmental damage, especially due to nitrogen's eutrophicating effect. As a result of the use of urea, oxygen depletion may occur in groundwaters, increasing the dissolution rate of heavy metals. At present, acetates, liquid potassium acetate and solid sodium acetate, as well as formates, potassium formate and sodium formate, are used at airports. In comparison to chlorides and urea, acetates and formates are less detrimental to the environment. Acetates and formates are effective in melting ice, but their drawback comprises the heavy corrosion of metals and electrical equipment. After the introduction of ice-melting agents based on acetate and formate, issues with asphalt pavements have been observed at airports. What is also significant in relation to the present invention is the fact that ice-melting agents based on acetate and formate have been found to cause heavy corrosion in aeroplane materials, including carbon fibre brakes, metal surfaces and mating metal-metal surfaces. All these issues caused by nominal deicing agents increase the risk of aviation safety.
In anticipatory slipperiness prevention, liquid ice-melting agent has been found to be the most usable form of an ice-melting agent, since a solid and often granular ice-melting agent is easily carried away from the intended surface under the influence of air flows. Further, the effect of granular ice-melting agent is very local, and therefore the effect starts fairly slowly and the applied amount is substantially higher than when a liquid or wetted substance is used. Liquid ice-melting agent is more easily distributed over the entire surface, thus covering a substantially larger proportion of the pavement surface than a solid substance. Previously, liquid substances comprising about 50% water have usually been used for the removal of hoarfrost and thin ice. To remove thicker ice, granular substances are required, which melt the ice down to the surface of the runway if necessary, after which the surface is cleaned by snowploughing or brushing. At present, liquid substances are mainly used (nearly 80% of all substances used) for the anti-skid treatment at airports, since a thick layer of ice is rarely allowed to form on the runway.
As a result of better understanding, environmental considerations and especially the accumulation of chemicals and their effect on the environment have gained increased significance. Especially in view of the environmental considerations concerning the former ice-melting agents, there is a great need for developing novel ice-melting agents that possess the efficacy necessary in the prevention of slipperiness.
EP 1034231 discloses a composition for anti-skid treatment in which aqueous solution comprising 10-60% betaine or its derivatives is used as an anti-freezing agent for runways and as an anti-skid agent for runways.
U.S. Pat. No. 6,596,189 discloses a liquid-based anti-freezing composition for airport runways, the composition exhibiting a minimal catalytic oxidative effect on carbon-carbon fibre composite brakes. This composition comprises mixtures of alkali and alkali earth metal carboxylates and alcohols, into which additional corrosion inhibitors have been added.

This patent is subject to a terminal disclaimer.

Substance composition and method for melting ice and preventing slipperiness and use of betaine for melting ice and preventing slipperiness


Provided is a management system for performing quality management on production equipment. A management system that includes: an acquisition component that acquires status information for production equipment that is subject to management; a detection component that, on the basis of the acquired status information, detects the occurrence of some event; and a display component that displays, separated according to inclusion in the four perspectives Machine, Man, Material, and Method, a plurality of factors that could be presumed to have caused the detected event in a manner in which the contents thereof and a probability of having caused the event can be compared.

With the progress of recent information and communication technology (ICT), further improvement of quality management for manufacturing equipment is required. As a configuration for performing such quality management, Japanese Patent Application Laid-Open (JP-A) No. 2015-153914 (Patent Literature 1) discloses a quality management device for managing a surface mounting line which performs a solder printing process of performing solder printing on a printed circuit board using a solder printing device, a mounting process of arranging electronic parts on the printed circuit board using a mounter, and a reflow process of solder-bonding the electronic parts using a reflow furnace. This quality management device provides a technology for reducing a likelihood of generation of defects by managing the surface mounting line in response to the operating state of the surface mounting line.

Management system and non-transitory computer-readable recording medium


The present invention relates to a method of manufacturing an exposure mask having an unprecedented supermicrostructure for an X-ray exposure method favorable for conventional supermicro exposure using lithography techniques. The method of manufacturing an X-ray exposure mask comprises the steps of alternately laminating two kinds of compound semiconductors as a thin film having a periodic structure with controllability of about one atomic layer on a substrate selectively etching only one material for forming the periodic structure, forming an uneven difference between adjacent layers of the laminate body, and manufacturing a mask for exposing streaks on a desired resist with the aid of a difference of X-rays absorption amounts between each layer by exposing X-ray in parallel to the direction of the laminate layer.

1. Field of Invention
The present invention relates to a method of manufacturing an exposure mask having an unprecedented supermicrostructure for carrying out an X-ray exposure method favorable for conventional supermicro exposure. The method employs lithography techniques to achieve microminiaturization resulting in better performance of high density integrated circuits and transistors for use in the electronics field.
2. Description of the Related Art
X-ray exposure lithography shows promise for providing a process that will achieve a breakthrough beyond the limits of present optical lithography techniques, as shown in FIGS. 1A and 1B.
However, X-ray exposure methods are proving difficult to implement. As a mask for preventing X-rays, a fine pattern of metal such as gold, tungsten and the like must be formed on a thin film. At present, an electron beam exposure method is being widely used as a technique which is not mass-producible but can draw a comparatively fine pattern. Consequently, frequent attempts have been made to form a fine metal pattern in combination with this exposure method using etching, lift-off and plating methods. However, it is very difficult to form a superfine metal pattern having a sufficient thickness by scattering electron beams in a resist or in structures under a resist such as a metal substrate or the like. This problem of supermicrostructure in electron beam exposure methods, limits supermicro-structures to about 10 nm of frequency at present.
On the other hand, in the formation of a layer structure, it is easy to provide film thickness controllability of about 1 nm. Oblique deposition is one example of a mask using the layer structure (see Appln. Phys. Lett., 36 (1), 1 Jan. 1980, American Institute of Physics). According to this method, as shown in FIGS. 1A and lB, a mask having about a 2 nm minimum ray width is formed on a periodically square-wave polyimide membrane by oblique deposition of carbon and tungsten, and a fine ray structure of up to 17.5 nm. However, the use of an oblique deposition method cannot minimize the period of a square wave.
At present, a thin film crystal growth method is the most closely studied method of forming a layer structure, and particularly in compound semiconductor crystal growth, composition switching controllability of less than one atomic layer is possible. At the same time, it is possible to grow crystal on the whole side surface of a deep groove. These advantages are due to crystal growth under such condition that migration of a growing seed on the crystal surface is selected to be large thereby maintaining flatness. Moreover, if thin film crystal growth is carried out by using single atomic layer epitaxial techniques, it is possible to form a thin film to within one atomic layer interval on the whole growth surface.
X-ray exposure is a method of going beyond the limits of optical wavelengths in the conventional exposure techniques. However, the difficulty of manufacturing an exposure mask has emerged as a new problem. That is, it is very difficult to form a very fine mask which can prevent penetration by X-rays on the order of 10 nm as required for an X-ray mask.

Method of manufacturing X-ray exposure mask


A structure of a storage box includes a main body, a stacking assembly, and a forward opening. The main body has an upper and front-facing opening and a recess on the rear. The stacking assembly is attached to the main body, covers the upper and front-facing opening, and has an upper cover and a front cover, the upper cover fitted to the front cover with a snap and having a convex portion, the shape of the convex portion identical to the shape of the recess. The forward opening is a part of the upper and front-facing opening of the main body and is covered by the front cover. When two or more storage boxes are stacked, the convex portion of the second storage box embeds the recess of the first storage box, preventing the entire structure from tilting forward when the front cover of the storage box above is opened.

At present, a large number of storage boxes used to store various types of objects exist, among which plastic shaped boxes with preset shapes that are easy to move are extremely common. Existing storage boxes basically make use of box bodies of a preset volume and shape formed from suitably strong plastic, while the upper opening of the box body can be covered with a cover of the desired shape so that objects are shielded from the outside after being placed within it.
Such storage boxes offer the function of convenient storage, however in addition to this single form of a cover used to cover the top end of the storage box, there are also a large number which have an opening extending to the front end and a front cover which limit the orientation, which in addition to being able to be lifted up to open, can also be slid open as appropriate for the sake of convenience, e.g. the patent for a "Storage Container" with publication number: 1560115, and utility model patent of Republic of China (Taiwan) for "Improved Structure of a Storage Box (21)" with publication number: M552902, both of which make reference to the use of covers to respectively cover the upper and front openings of storage boxes for the convenience of the user in opening the cover in the suitable orientation according to the particular arrangement in order to insert or remove objects. In this respect, by combining a front cover with the front opening of the storage box referred to in the latter document, the application of the opening/closing components is improved, so that the front cover can be pivotally connected to the body through simple implementation, being temporarily limited in a stable orientation or for storage boxes covered with a front cover and upper cover, when being stacked up, the convex portion extending from the back section of the upper cover can be introduced into the corresponding concave portion of the main body above to prevent the stacked upper storage box from tilting forward when the front cover is opened to insert or remove items.


A photochromic structure includes a plastic support of optical grade with good light transparency, having at least one face with an adhesive layer impregnated with a solution of a solvent with photochromes, having a flexible host matrix for the photochromes, which is mounted by adhesion onto another support. A structure with a uniform flexible photochromic matrix, which has rapid transition times, notably a rapid relaxation time, is thus obtained. The structure is mountable, and advantageously repositionable. It is produced via a process using roll-milling combined with a system for dispensing the solvated solution of photochromes upstream of the rolls, via which a support strip of an adhesive is entrained by the rolls, and the adhesive is gradually impregnated and then laminated on another support.

Photochromic materials are used for producing an optical function for an adaptive light filter or screen, typically an adaptive (UV) sunscreen.
Photochromism is defined as being the property of a material to react to the intensity of a given radiation, typically UV radiation, by modifying its visible-light absorption properties: the material darkens under the effect of the radiation, and lightens in the absence of this radiation. This phenomenon of lightening and darkening is reversible. Photochromic mineral and organic materials are thus found in the glass industry. According to the prior art, mineral or organic photochromic materials are obtained by incorporating photochromic substances into a material, by various known techniques. For example, photochromic organic materials are obtained, before polymerization, by mixing photochromic molecules (for example spirooxazine molecules) with a liquid monomer, or, after polymerization, by surface impregnation via a heat treatment (heat transfer). Photochromic mineral materials will be obtained, for example, by introducing silver halide crystals into the material.
The known photochromic materials have various drawbacks. The manufacturing processes used make them expensive. Notably, optical spectacle glasses incorporating such an optical property are expensive. For these reasons, it is difficult to envisage proposing cheap spectacles, of disposable type, incorporating such functionality, which might, however, be of interest to users of this type of product.
This cost also prevents their use in applications in which the surfaces concerned are relatively large, which limits their potential applications. Now, the integrated optical filter function of these materials is potentially advantageous for many products or articles such as helmet visors, for pilots, for example aircraft pilots, or protective helmets of any type for the construction, public works, sports goggles (cycling), etc. sectors, this list being by no means limiting.
Another drawback of these materials is the relatively slow transition time between the two darkened and lightened states: excitation time, for passing from the resting state to the excited state of the photochromic molecules in the presence of a given radiation, and relaxation time for passing from the excited state to the resting state, in the absence of radiation. These transition times are dependent on the solid nature of the host matrix, mineral or organic glass, which receives the photochromic molecules. Notably, the slowness of relaxation may prove to be a great inconvenience during use. Finally, as regards optical materials, the problem of replacing or repairing them, notably in the event of scratching, still arises.

Multilayer structure having a photochromic host matrix and manufacturing method

Essilor International (Compagnie Generale d'Optique)


Inventive systems and methods for the generation of energy using thermophotovoltaic cells are described. Also described are systems and methods for selectively emitting electromagnetic radiation from an emitter for use in thermophotovoltaic energy generation systems. In at least some of the inventive energy generation systems and methods, a voltage applied to the thermophotovoltaic cell (e.g., to enhance the power produced by the cell) can be adjusted to enhance system performance. Certain embodiments of the systems and methods described herein can be used to generate energy relatively efficiently.

Thermophotovoltaic (TPV) systems produce electricity via the use of an emitter that thermally radiates photons, which can be subsequently converted into electron-hole pairs within a photovoltaic (PV) medium. These electron-hole pairs can be conducted to leads within the system to produce a current. Because they are solid-state devices, TPV systems have the potential for relatively high reliabilities, relatively small form factors (e.g., meso- and micro-scales), and relatively high energy densities compared to, for example, traditional mechanical engines. However, many emitters within TPV systems emit a large amount of thermal photons with energies below the electronic bandgap of the TPV cell, which are absorbed as waste heat within the system. In many cases, this phenomenon produces TPV system efficiencies well below those of their mechanical counterparts operating at similar temperatures. For these reasons, among others, there exists a need for more effective systems and methods for generating energy using thermophotovoltaic cells.