A film deposition apparatus to form a thin film by supplying first and second reaction gases within a vacuum chamber includes a turntable, a protection top plate, first and second reaction gas supply parts extending from a circumferential edge towards a rotation center of the turntable, and a separation gas supply part provided therebetween. First and second spaces respectively include the first and second reaction gas supply parts and have heights H1 and H2. A third space includes the separation gas supply part and has a height H3 lower than H1 and H2. The film deposition apparatus further includes a vacuum chamber protection part which surrounds the turntable and the first, second and third spaces together with the protection top plate to protect the vacuum chamber from corrosion.

1. Field of the Invention
The present invention generally relates to film deposition apparatuses, substrate processing apparatuses, film deposition methods and storage media, and more particularly to a film deposition apparatus, a substrate processing apparatus and a film deposition method for forming a thin film by alternately supplying at least two kinds of source gases, and to a computer-readable storage medium which stores a program which, when executed by a computer, causes the computer to execute such a film deposition method.
2. Description of the Related Art
As a film deposition method of a semiconductor fabrication (or manufacturing) process, there is a known process which causes a first reaction gas to adsorb on a surface of a semiconductor wafer (hereinafter simply referred to as a "wafer"), which is used as a substrate, under a vacuum environment, and thereafter switches the gas that is supplied to a second reaction gas, in order to form one or a plurality of atomic or molecular layers using the reaction of the two gases. Such a deposition cycle is performed a plurality of times to stack and deposit the layers on the substrate. This known process is referred to as the Atomic Layer Deposition (ALD) or Molecular Layer Deposition (MLD). According to this known process, the film thickness can be controlled with a high accuracy depending on the number of cycles performed, and a satisfactory in-plane uniformity of the film quality can be achieved. Therefore, this known process is a promising technique that can cope with further reduced film thicknesses of semiconductor devices.
Such a film deposition method may be used to deposit a dielectric film having a high dielectric constant for use as a gate oxide film, for example. When silicon dioxide (SiO2) is deposited as the gate oxide film, a bis(tertiary-butylamino)silane (BTBAS) gas or the like is used as a first reaction gas (source gas) and an ozone gas or the like is used as a second gas (oxidation gas).
In order to carry out such a film deposition method, the use of a single-wafer deposition apparatus having a vacuum chamber and a shower head at a top center portion of the vacuum chamber has been under consideration. In such a film deposition apparatus, the reaction gases are introduced into the chamber from the top center portion, and unreacted gases and by-products are evacuated from a bottom portion of the chamber. When such a deposition chamber is used, it takes a long time for a purge gas to purge the reaction gases, resulting in an extremely long process time because the number of cycles may reach several hundred. Therefore, a film deposition method and a film deposition apparatus that can achieve a high throughput are desired.
Under these circumstances, film deposition apparatuses having a vacuum chamber and a turntable that holds a plurality of wafers along a rotating direction have been proposed.
A U.S. Pat. No. 7,153,542 proposes a film deposition apparatus with a vacuum chamber which has a flat cylinder shape and is divided into right and left areas. Each of the right and left areas has an evacuation port which is formed along a semi-circular contour thereof and is provides upward evacuation. In addition, a separation area formed with a gas inlet port for introducing a separation gas is provided between the right semi-circular contour and the left semi-circular contour, that is, at a diametrical area of the vacuum chamber. Supply areas for mutually different source gases are formed in the right semi-circular area and the left semi-circular area. A work piece passes through the right semi-circular area, the separation area, and the left semi-circular area by rotating a turntable within the vacuum chamber, and the source gases are evacuated via the evacuation port. A ceiling of the separation area to which the separation gas is supplied is lower that that of the supply areas to which the source gases are supplied.
A Japanese Laid-Open Patent Publication No. 2001-254181 proposes a film deposition apparatus in which four wafers are arranged at equal distances on a wafer support member (turntable) along the rotating direction. First and second reaction gas ejection nozzles are arranged at equal distances along the rotating direction in order to oppose the wafer support member. Purge nozzles are arranged between the first and the second gas ejection nozzles. The wafer support member is rotated horizontally. Each wafer is supported by the wafer support member, and an upper surface of the wafer is higher than an upper surface of the wafer support member by an amount corresponding to the thickness of the wafer. The distance between the nozzles and the wafer is 0.1 mm or greater. Vacuum evacuation is made from between the outer edge of the wafer support member and the inner wall of the process chamber. According to this film deposition apparatus, a so-called air curtain is generated below the purge gas nozzles, to thereby prevent the first and second reaction gases from being mixed.
A Japanese Patent No. 3144664 proposes a film deposition apparatus with vacuum chamber that is divided into a plurality of process chambers along the circumferential direction by a plurality of partitions. A circular rotatable susceptor on which a plurality of wafers are placed is provided below the partitions, with a slight gap between the susceptor and the partitions.
A Japanese Laid-Open Patent Publication No. 4-287912 proposes a film deposition method which divides a circular gas supply plate into 8 sections in the circumferential direction, and arranges a AsH3 gas supply port, a H2 gas supply port, a TMG gas supply port and a H2 gas supply port at 90 degree intervals. Further, evacuation ports are provided between the gas supply ports. A susceptor which supports a wafer and opposes the gas supply plate is rotated.
A U.S. Pat. No. 6,634,314 proposes a film deposition apparatus in which an upper area of a turntable is divided into four quarters by four partition walls, and a wafers is placed in each of the four partitioned areas. A source gas injector, a reaction gas injector, and a purge gas injector are alternately arranged in the rotating direction in order to form a cross-shaped injector unit. The injector unit is rotated horizontally so that the injectors sequentially oppose the four partitioned areas, and a vacuum evacuation is made from a periphery of the turntable.
A Japanese Laid-Open Patent Publication No. 2007-247066 proposes a film deposition apparatus for an atomic layer Chemical Vapor Deposition (CVD) that causes a plurality of gases to be alternately adsorbed on a target (corresponding to a wafer). In this apparatus, a susceptor that holds the wafer is rotated, while source gases and purge gases are supplied from above the susceptor. Paragraphs 0023 to 0025 of the Japanese Laid-Open Patent Publication No. 2007-247066 describe partition walls that extend in a radial direction from a center of a chamber, and gas ejection holes that are provided below the partition walls in order to supply the source gases or the purge gas to the susceptor, so that an inert gas is ejected from gas ejection holes to generate a gas curtain. Regarding evacuation of the gases, paragraph 0058 of the Japanese Laid-Open Patent Publication No. 2007-247066 describes that the source and purge gases are evacuated separately through respective evacuation channels 30a and 30b. Techniques similar to that proposed in the Japanese Laid-Open Patent Publication No. 2007-247066 are also proposed in U.S. Patent Application Publications No. US2007/0218701 and No. US2007/0218702.
However, the following problems are encountered when a film deposition process is performed using the film deposition apparatus or the film deposition method proposed in the eight patent documents described above, by arranging a plurality of substrates on the turntable within the vacuum chamber in the rotating direction.
According to the film deposition apparatus and the film deposition method proposed in the U.S. Pat. No. 7,153,542, the upward evacuation port is provided between the separation gas ejection hole and the reaction gas supply area, and the reaction gas is evacuated from the evacuation port together with the separation gas. For this reason, the reaction gas ejected onto the work piece forms an upward flow and is sucked into the evacuation port, to thereby blow particles upwards which may contaminate the wafer.
According to the film deposition apparatus and the film deposition method proposed in the Japanese Laid-Open Patent Publication No. 2001-254181, the air curtain generated from the purge gas nozzles cannot prevent mixture of the reaction gases and may allow the reaction gases on both sides particularly from the upstream side of the rotating direction to flow through the air curtain, because the wafer support member rotates. In addition, the first reaction gas discharged from the first gas outlet nozzle may flow through the center portion of the wafer support member corresponding to the turntable and reach the second reaction gas discharged from the second gas outlet nozzle. If the first reaction gas and the second reaction gas mixed above the wafer, a reaction product is adsorbed on the wafer surface, and it becomes difficult to perform a satisfactory ALD (or MLD) process.
According to the film deposition apparatus and the film deposition method proposed in the Japanese Patent No. 3144664, the process gas may diffuse into the adjacent process chamber from the gap between the partition and the susceptor or the wafer. In addition, because an evacuation chamber is provided between a plurality of process chambers, the gases from the process chambers on the upstream side and the downstream side mix into the evacuation chamber when the wafer passes through the evacuation chamber. Accordingly, the film deposition technique employing the ALD cannot be applied to the proposed film deposition apparatus and the proposed film deposition method.
According to the film deposition apparatus and the film deposition method proposed in the Japanese Laid-Open Patent Publication No. 4-287912, no realistic means is proposed on how to separate the two reaction gases, and the two reaction gases will mix not only in a vicinity of the center of the susceptor but will actually also mix in a region other than the vicinity of the center of the susceptor where the H2 gas supply port is arranged. In addition, when the evacuation port is provided in a surface opposing the region where the wafer passes, the wafer is easily contaminated by the particles that are blown upwards from the susceptor surface.
According to the film deposition apparatus and the film deposition method proposed in the U.S. Pat. No. 6,634,314, after the source gas or the reaction gas is supplied to each partitioned area, it takes a long time to flush the environment of the partitioned area by the purge gas from the purge gas nozzle. Moreover, the source gas or the reaction gas may diffuse from one partitioned area to an adjacent partitioned area by riding over a vertical wall, and the two gases may react in the partitioned area.
According to the film deposition apparatus and the film deposition method proposed in the Japanese Laid-Open Patent Publication No. 2007-247066, the U.S. Patent Application Publication No. US2007/0218701 or the U.S. Patent Application Publication No. US2007/0218702, the source gases may flow into a purge gas compartment from source gas compartments located on both sides of the purge gas compartment and become mixed with each other in the purge gas compartment. As a result, a reaction product is generated in the purge gas compartment, which may cause particles to contaminate the wafer.
Furthermore, according to the film deposition apparatuses and the film deposition methods proposed in the U.S. Pat. No. 7,153,542, the Japanese Laid-Open Patent Publication No. 2001-254181, the Japanese Patent No. 3144664, the Japanese Laid-Open Patent Publication No. 4-287912 and the U.S. Pat. No. 6,634,314, when the film deposition is performed by supplying a corrosive reaction gas including Cl or the like as the first reaction gas or, when a corrosive cleaning gas including Cl or the like is supplied after the film deposition from the nozzle which supplies the first reaction gas, corrosion of portions made of an aluminum material, such as the ceiling of the vacuum chamber, occurs.

Film deposition apparatus, substrate processing apparatus, film deposition method, and storage medium


A wireless receiver and method employs a forward/backward recursive covariance based filter coefficient generation scheme for equalizing a received wireless signal, such as a CDMA signal or other suitable signal. A forward/backward recursive covariance based filter coefficient generating circuit (206) includes a forward recursion portion (300) that receives data representing channel estimates (18) of a communication channel, and data representing an auto-covariance matrix (22). The forward recursion portion (300) produces a set of output values (306) from each iteration stage (400a–400n) of the forward recursion portion (300). The set of output values (306) are stored and a backward recursion portion (302) obtains the set of output values (306) and also receives the data representing the auto-covariance matrix (22), and generates filter coefficients (208) based on this information.

Wireless communication systems, including but not limited to, cellular systems, such as code division multiple access systems (CDMA) are known to use wireless receivers that employ variations of Weiner filter structures to compensate for channel related variations. Such channel variations can result in signal fading or multi-path signals that arrive at a receiver's antenna at different times depending upon their route from a transmitting antenna. As such, copies of the same signal may be received and are combined in a manner to improve received signal strengths. Channel equalizers, as known in the art, include filters that attempt to use energies of various copies to get a stronger signal. For example, approximations of Weiner filters are used in an attempt to correct for signal reductions and variations caused by channel conditions. As such Weiner filters are used to approximate an inverse of a channel's characteristics. As known in the art it is desirable to reduce errors of equalizers.
Also, for CDMA systems, it is known for example to use pilot sequences that are used to send known information so that a wireless receiver can determine channel characteristics. As such, wireless receivers are known to include a receiving antenna that is coupled to a radio frequency section which performs demodulation and other functions. The receiver may also include a square root raised cosine filter, a channel equalizer, a log likelihood ratio extraction circuit and a turbo decoder to decode received voice information. The channel equalizer circuitry may employ for example lattice multistage Weiner equalizers. The Weiner equalizers work in the time domain for example.
Chip level equalizers have been proposed for high speed downlink packet access as a mechanism of suppressing inter-code interference. By virtually restoring the orthogonality of the downlink channels, these chip level equalizers help avoid a main performance limitation of a RAKE receiver, and can dramatically improve system performance. A low complexity approximation to a Weiner filter would be useful.
FIG. 1 illustrates one example of a known channel equalizer 10 is operatively coupled to a receiving antenna 12 through one or more signal processing stages. As shown, a fast Fourier transform stage 14 changes the received wireless signal you into the frequency domain. The resultant received signal y(f) is then passed to a channel estimator circuit 16 which produces for example channel estimates for a group of chips represented as channel estimates PD 18. The received signal is also passed to an auto-covariance estimator 20 which produces data representing an auto-covariance matrix 22. The received signal is also buffered by buffer stage 24 until filter coefficients are determined. Buffer 24 may be a plurality of fast Fourier transforms as known in the art. The channel estimates 18 and the data representing the auto-covariance matrix 22 are received by a filter coefficient estimator 26 which may be, for example, a forward recursive covariance based coefficient generator, such as that described for example in an article entitled "Reduced Rank Adaptive Equalization", authored by Yakun Sun, dated Jan. 30, 2001 which describes reduced rank adaptive space time equalization. Such coefficient generators generate filter coefficients 28 for an equalizer circuit 30 to suitably program the equalizer 30 (i.e. filter) to compensate for channel characteristics. Such coefficient generators are also sometimes referred to minimum mean squared error equalizer coefficient generators.
However, forward recursive covariance based coefficient generators typically require the calculation of normalized cross covariance vectors which when implemented in digital processors or other hardware, may be difficult to program. As such receivers may be more costly than necessary. In addition, such equalizer operations tend to operate in a forward recursion fashion only and can result in increasing vector sizes resulting from the numerous forward recursions.

Wireless receiver and method employing forward/backward recursive covariance based filter coefficient generation


An imaging system and method are disclosed. In one aspect, the system includes an edge-detecting module detecting edge coordinates in a first image; first and second disparity-estimating modules respectively configured to obtain a first and second estimated disparity map, a cross-checking module configured to cross check the first estimated disparity map using the second estimated disparity map to identify occlusion pixels in the first estimated disparity map, an occlusion-refining module configured to refine the occlusion pixels by identifying at least a pixel under refinement on the first estimated disparity map as occluded based on the number of occlusion pixels in a refining base region, and a hole-filling module configured to fill the refined set of occlusion pixels. The imaging system improves the quality of a disparity map and controls the complexity of stereo-matching.

1. Field of the Invention
The disclosed technology relates to the field of computer vision, and more particularly to an imaging system and method that generate a depth map.
2. Description of the Related Technology
Stereo-matching estimates disparity distances between corresponding pixels in a pair of stereo images or videos captured from parallel cameras in order to extract depth information of objects in a scene. Stereo-matching has many applications such as 3D gesture recognition, viewpoint synthesis, and stereoscopic TV.
In general, imaging methods that generate a depth map can be classified into two categories: global and local methods.
Global methods usually formulate the stereo-matching problem as an energy function with the objective to find a disparity function d that minimizes a global energy. The energy function may be expressed by the following equation.E(d)=Edata(d)+λEsmooth(d)  (1)where Edata(d) measures how well the disparity function d agrees with the stereo image pair, and Esmooth(d) encodes the smoothness assumptions made by the method, and measures differences between neighboring pixels' disparities. Once the energy function is formulated, it may be minimized using, for example, dynamic programming, graph cuts and belief propagation.
Local methods estimate a disparity distance of a pixel independently over a window. Matching costs for the pixel in one of the stereo images and a candidate matching pixel in the other of the stereo images are aggregated over the window. The minimum matching cost among a plurality of candidate matching pixels with different disparity distances may be identified for selection of the disparity level of the pixel on a disparity map.
For both of the methods, there exists a tradeoff between depth map quality and computational complexity. For example, for global methods, the smoothness term Esmooth(d) in the energy function may use a larger neighborhood such as a neighborhood of 8 instead of 2 in order to obtain better boundaries. However, the computational complexity for optimizing the global energy is approaching being intractable. For local methods, the complexity is much lower than that of the global methods but at the cost of quality. To enhance quality, a higher number of bits may be used to represent a pixel so as to obtain a finer disparity map. However, matching cost calculation and aggregation is performed on per-pixel basis. With the higher number of bits per pixel, the computational complexity is significantly increased.
Therefore, it is highly desirable to provide an imaging system and method that achieve an enhanced quality of disparity map without aggravating the complexity of the more computationally intensive part of the imaging system and method.


A base unit includes a sensor calibration function. When a user communicatively couples a consumer electronic device having a sensor to the base unit, a controller at the base unit retrieves a calibration reference value for the sensor and/or a sensor algorithm that utilizes data output by the sensor. The base unit then sends the calibration reference value to the consumer electronic device to set a sensor calibration parameter associated with the sensor and/or the sensor algorithm.

There are many different types of communication devices currently available. However, one particular type of device presently enjoying an astounding increase in popularity is the Smartphone. One of the reasons for this popularity is that the Smartphone provides functionality that far exceeds that provided by a simple communications device. Particularly, Smartphones generally utilize a touch-sensitive display to allow their users to interact directly with one or more computer applications stored in memory on the device.
One particularly useful application is a navigation application. Specifically, most Smartphones have an integrated Global Positioning Satellite (GPS) receiver for receiving navigational signals from a plurality of satellites. Based on these signals, the Smartphone can calculate its current position almost anywhere on the Earth's surface and display that position to the user on a touch-sensitive display. Further, given the current location, the application can calculate a route to a destination location for the user.
Historically, GPS applications were limited by the need to be within the "line-of-sight" of multiple satellites. Therefore, while a GPS application may provide an accurate position fix before the user enters a building, it is difficult for the GPS application to determine the user's position after the user enters the building. The difficulties in providing an accurate indoor position fix can be amplified depending on various factors, such as the construction of the building. Thus, with some GPS applications, it is almost impossible to accurately determine what floor the user is on, as well as whether the user is a particular room or part of the building.
To address such situations, manufacturers have started integrating a variety of different sensors into their Smartphone devices. One such sensor is a pressure sensor. Generally, pressure sensors are Microelectromechanical System (MEMS) devices that measure changes in atmospheric pressure. With a pressure sensor, a given GPS application may be able to differentiate changes in altitude of less than 1 meter. Thus, a Smartphone equipped with a GPS application and a pressure sensor can be used to determine which floor of a multi-story building that a user is currently occupying.
Additionally, pressure sensors can be placed into different items or devices that are wearable by people, such as headsets, jewelry, head gear, watches, and so-called "smart" clothing, and used to track their positions within a building. Further, in addition to pressure sensors, other types of sensors, such as a magnetometer, an accelerometer, and/or a gyroscope, may also be integrated within the Smartphone or other device and utilized by the GPS application to estimate a person's location within the building (e.g., within a specific room), or to facilitate the functions of gaming applications, bio or chemo sensor applications, or communications applications, for example.
Thus, sensors have many different uses and may be integrated into many different types of devices; however, whatever their use or function, the sensors need not be contained within any one single item or device, such as the Smartphone. Instead, the sensors may be distributed across different items and devices. However, to ensure that the sensors and the sensor algorithms that use the sensor data function accurately, the sensors must be calibrated. Sensor calibration can be quite difficult, especially where the sensors are distributed across different items and/or devices.

System and method for calibrating sensors across loosely coupled consumer electronic devices


A basketball training apparatus for use with a basketball goal is secured to a backboard, the apparatus including a blocking element secured to the backboard. In an embodiment, the blocking element is a generally planar ledge secured to the backboard at a height substantially equal to the height of a top surface of the basketball goal. The generally planar ledge can be constructed to include a center portion extending outwardly from a center of the backboard. A right side portion can extend outwardly from the backboard along a right side of the backboard from the center portion to a right edge of the backboard, and a left side portion can extend outwardly from the backboard along a left side of the backboard from the center portion to a left edge of the backboard.

As chronicled by historian Mary Bellis on About.com, the Canadian physician and educator James Naismith invented basketball in December 1891. Prompted by the request of his superior to produce an alternative for students bored with the traditional winter physical education routines of calisthenics and gymnastic in Springfield, Mass., Naismith affixed two peach baskets to a 10-foot-high railing. Students scored points by tossing a soccer ball into the basket, governed by a set of rules eventually published by Naismith in 1892.
Although no contemporary record of the details of the first basketball game exists, it is likely that at least one of the players in that nascent contest had a can't-miss, point-blank shot bounce off of the backboard, roll off the rim of the peach basket, and fall harmlessly away. It is perhaps fortunate for those players that history has forgotten the name of the first player to blow a lay-up. It has certainly become apparent in the intervening century of basketball that there is a need for increased shooting accuracy from all ranges, including close range.
In an attempt to satisfy this need, a variety of basketball shooting training devices have been devised. Many of these devices are represented in the patent literature. For example, U.S. Pat. No. 6,190,270 Barry is directed to an athletic shooting aid adapted to be detachably mounted directly on the goal of a sporting event to provide a target at which the player aims and strikes with the game piece in order to improve the form and accuracy of the player's shooting. The device comprises a clamp which is removably attachable to the goal having a substantially straight elongated member extending from the clamp with a ball or target of material attached to the elongated member to serve as the target at which the player aims when shooting the game piece. The elongated member is adapted and configured to allow the ball to move when struck by the game piece in such a manner that the game piece deflects the ball without substantially affecting the trajectory of the game piece and to allow the ball to be repositioned after the game piece has passed through the goal.
In another example, U.S. Pat. No. 4,226,416 to Callahan deals with a basketball practice assembly that may be removably secured to a back board supported hoop in a desired position to assist a player in improving his ability to make successful free throws or side shots. The practice assembly is of such design that two of them may be oppositely positioned on side portions of a basketball hoop to permit two players to simultaneously practice side shots.
Similarly, U.S. Pat. No. 4,206,915 Woodcock discusses a basketball practice device adapted to be detachably mounted on a standard basketball goal to improve the form of the players in shooting goals. The device comprises a base which can be clamped to a standard basketball goal. This base has a plurality of radially outwardly extending members joined thereto. The outermost ends of the radially extending members have free-standing vertical elements so that they extend upwardly from the goal to deflect basketball shots having an undesirable trajectory.
Despite these and other training devices, basketball players at every level are still missing an unnecessarily high number of shots. The fact that many of these shots are easy lay-ups is distressing, not only to the players themselves, but to coaches and fans as well. It can thus be seen that the need exists for a simple, inexpensive, training device that will effectively increase the shooting skill of basketball players.


A transaction message processing server is configured to receive an authorization request message from a sender computing device, the authorization request message associated with a transaction. The server is also configured to detect a decision data element in an authentication outcome data field of the authorization request message, and interpret the decision data element as an indicator that the transaction is highly authenticated. The server is further configured to retrieve a reason code that identifies the transaction as a highly authenticated transaction, and embed the reason code into the authorization request message to form an enhanced authorization request message. The server is still further configured to transmit the enhanced authorization request message including the reason code to an issuer computing device, wherein the enhanced authorization request message is configured to enable the issuer computing device to bypass at least one issuer authentication process.

This disclosure relates to computer message processing, and, more particularly, to expedited processing of authenticated computer messages.
At least some known credit/debit card purchases involve the exchange of a number of payment card network messages between merchant, acquirer, and issuer members of a multi-party interchange model. Such messages may include authorizations, advices, reversals, account status inquiry presentments, purchase returns and chargebacks. The credit or debit card payment transaction messages may include several transaction attributes, such as, but, not limited to, primary account number (either real or virtual), transaction amount, merchant identifier, acquirer identifier (the combination of which with above uniquely identifies a merchant), transaction date-time, and address verification.
In order to detect and prevent fraudulent transactions, one or more parties to the transaction perform one or more fraud "scoring" or authentication processes. However, at least some parties may have limited access to certain information when performing their own fraud scoring processes, which can lead to inconsistent and/or incompatible outcomes (e.g., one party with more information may approve a transaction while another party with less information may decline the transaction). At least some known systems have attempted to overcome these issues by making more information associated with a transaction available to more parties across the transaction processing system.

Systems and methods for expedited processing of authenticated computer messages


A three piece belly-band crossmember is provided which may be installed as a single assembly and from which the center subassembly may be removed after installation, allowing access to the vehicle powertrain. The crossmember maintains integral strength as a result of a tab and slot arrangement and overlapping frame mounting holes between its three subassemblies. It may be provided with a suspension component mounting point. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Vehicles for operation on the ground, particularly trucks and heavy vehicles, are commonly provided with a structural frame to which the body, powertrain, and running gear are mounted. This structural frame often comprises a set of frame rails that are connected by several crossmembers to form a ladder-type vehicle frame. Two or more axles are attached to suspension assemblies, which are in turn attached to various mounting points on this vehicle frame. An engine and transmission, together comprising the vehicle powertrain, are mounted between the rails upon elastic mounts, typically towards the front of the vehicle. A vehicle cab is also attached to the vehicle frame, often by means of elastic mounts. For each of the suspension mounting points, cab mounts, and engine and transmission mounts, suitable brackets must be used to attach the mounts to the frame.
Because of the location of the engine and transmission, and because the structural frame must bear the loads generated by the front suspension, the weight of the engine and transmission, and often the vehicle cab in the same area, one or more special crossmembers are used to tie the frame rails together while providing clearance for the engine and transmission. These special crossmembers are sometimes referred to as horse-collars or belly-bands.
It is advantageous to maximize the functionality of each subcomponent of a vehicle frame, in order to minimize weight and costs associated with manufacturing. Accordingly, it would be advantageous to use the belly-band crossmember for such purposes as providing a mounting point for suspension components or vehicle cab mounts. It is also advantageous to accommodate serviceability in the design of the vehicle, by making it possible to remove certain components without requiring extensive disassembly of the completed vehicle.

Suspension mounting crossmember with integrated cab mounts for vehicle having front multilink suspension

International Truck Intellectual Property Company, LLC


In a preferred embodiment, a swimming simulator, including: a horizontal frame to support a user in a horizontal plane above a surface on which the simulator is disposed, with the user's shoulders near a front edge of the frame and the user's hips near a rear edge of the frame; supports to support the frame spaced above the surface; two generally horizontal bars extending outwardly from the sides of the frame, the proximal ends of the bars being rotatably attached to the frame such that the distal ends of the horizontal bars can move arcuately in generally horizontal planes; resistances disposed at selected points between the proximal and the distal ends of the horizontal bars to resist the arcuate movement; hand grips attached to the distal ends of the horizontal bars, the hand grips being graspable by the user to move the horizontal bars in the arcuate movement.

1. Field of the Invention
The present invention relates to exercise and training devices generally and, more particularly, but not by way of limitation, to a novel swimming simulator for the teaching and training of swimmers.
2. Background Art
There have been a number of devices designed for the water-free simulation of the motions of swimming. Many of these devices employ systems of weights and pulleys and all are relatively complicated. Some are suitable only for semipermanent installation in gymnasiums or commercial operations.
A significant disadvantage of such known devices is that, in some cases, the arm motions for the three most common swimming strokes --crawl, back, and butterfly -- cannot be simulated satisfactorily with one device. In other cases, resistance is not provided during both the pulling and return portions of a stroke. These disadvantages derive largely from the linkages in the purely mechanically joined motion devices limiting the range of motion and the springs and pulleys in the devices employing those not providing sufficient training resistance during the return portion of a stroke.
Accordingly, it is a principal object of the present invention to provide a swimming simulator that is simple in construction.
It is a further object of the invention to provide such a simulator that is easily disassembled for storage and transportation.
It is an additional object of the invention to provide such a simulator that is readily adjusted for varying degrees of resistance and/or for differing sizes of users.
It is another object of the invention is to provide such a simulator that can be employed to simulate arm motions for the crawl, back, and butterfly strokes.
A further object of the invention is to provide a simulator that provides resistance during both the pulling and return portions of an arm stroke.
Other objects of the present invention, as well as particular features, elements, and advantages thereof, will be elucidated in, or be apparent from, the following description and the accompanying drawing figures.


A protective housing for a biological indicator for testing the effectiveness of a sterilization procedure comprises a tube constructed of a liquid impermeable and gas-nonabsorptive polymer, a cap assembly having an aperture that allows sterilant to enter the housing during the sterilization procedure and contact the biological indicator, and an absorptive material in the cap assembly to prevent condensed sterilant from entering the housing and contacting the biological indicator. During a sterilization procedure the protective housing reduces premature inactivation of biological indicators, especially biological indicators that measure the effectiveness of a sterilization procedure by monitoring an enzyme whose activity can be correlated with the viability of at least one microorganism commonly used to monitor sterilization efficacy.

Biological indicators are recognized in the art as providing an accurate and precise means for testing the effectiveness of a sterilization procedure. Conventional biological indicators gauge the effectiveness of a sterilization cycle by monitoring the survival of a test microorganism that is many times more resistant to the sterilization process than most organisms that would be present by natural contamination. The biological indicator is exposed to a sterilization cycle and then incubated under conditions that will promote the growth of any surviving test microorganisms. If the sterilization cycle fails, the biological indicator generates a detectable signal that the biological specimen survived. The detectable signal may, for example, be luminescent, fluorescent, color or radiation.
One well-known type of biological indicator uses spores from bacteria or fungi to test the effectiveness of a sterilization procedure. Biological indicators of this type commonly employ a nesting tube arrangement, in which a smaller inner tube that contains spore growth media nests within a larger tube having a gas-permeable cap. The inner tube is made of glass or some other frangible material and is completely sealed. The outer tube is made of a compressible plastic. The spores are impregnated upon filter paper or some other appropriate carrier, which is located between the walls of the outer and inner tubes during the sterilization procedure. The sterilant enters this void through the cap and contacts the spores during the sterilization procedure. Afterward the inner tube is broken, exposing the spores to the growth media. The biological indicator is then incubated in conditions that promote the growth of viable spores. If spores survive the sterilization cycle, a pH indicator in the growth medium will change color, indicating that the sterilization cycle has failed. Although accurate, biological indicators that rely on the growth of spores are slow, commonly requiring between 1 and 7 days to give final results. During the incubation period, the goods must be quarantined, and a large amount of space must be committed to their storage.
More recently biological indicators have been developed that measure the effectiveness of sterilization cycles by monitoring an enzyme whose activity can be correlated with the viability of at least one microorganism commonly used to monitor sterilization efficacy. In contrast to biological indicators that measure spore growth alone, enzyme indicators provide fast results, often in as little as one to three hours. If the sterilization procedure works properly, the enzyme will be inactivated during the cycle. If, however, the sterilization procedure fails, the enzyme will retain its activity and react with a substrate to form a detectable product. Enzyme biological indicators include a source of active enzyme and a substrate that reacts with the enzyme. The enzyme and substrate are separated from each other by a physical barrier during the sterilization cycle, and are mixed together afterward. The formation of an enzyme-substrate product is detectable as a fluorescent or color change. Enzyme biological indicators are described in U.S. Pat. No. 5,073,488, which is incorporated in its entirety herein by reference.
Enzyme biological indicators may be used alone or as part of a dual biological indicator. Dual biological indicators are enzyme biological indicators that measure both enzyme activity and spore growth to determine the effectiveness of a sterilization cycle. The enzyme system gives rapid results, which are then confirmed by measurement of spore outgrowth. In a dual biological indicator the spores themselves may be the source of active enzyme. 3M.TM. Attest.TM. 1291 and 1292 Rapid Readout Biological Indicators, available from 3M Company, St. Paul, Minn., are dual indicators that measure both enzyme activity and the growth of live spores.
Although enzyme biological indicators are both rapid and accurate for most uses, it has been observed that when certain pre-vacuum, or vacuum assisted, steam sterilization protocols are followed the enzyme may be prematurely inactivated, leading to false indications of sterility or false negatives. When these sterilization procedures are used, dual indicators may show positive signs of spore growth even though the indicator showed no signs of enzyme activity. This is not a problem in the United States, where steam is introduced to the sterilization chamber before a vacuum is drawn. However, in Europe, where pre-vacuum sterilizers often draw a vacuum before steam is introduced, it is known that the enzyme is sometimes inactivated before the spores are killed. When this occurs, the enzyme is unable to form an enzyme-substrate complex that indicates that the sterilization cycle has failed, and contamination goes undetected. Although the precise mechanism underlying this problem is not known with certainty, it is believed that in European pre-vacuum cycles condensed sterilant contacts the enzyme and inactivates it.
There is a need for a protective housing for a biological indicator that will prevent condensed sterilant from contacting the biological indicator and inactivating it prematurely, but that will allow noncondensed sterilant to enter the housing and contact the biological indicator.

Protective housing for biological indicator for testing the effectiveness of a sterilization procedure

Minnesota Mining and Manufacturing Company


A device for holding identification information for pets is disclosed. The device is attachable to a collar, harness or leash. The device permits new identification information to be placed within it. Identification information may be placed within a slot located on the side of the device or can alternatively be placed inside the device by opening a securing member that can function like a door.

1. Field of the Invention
The invention relates to the field of pet products. In particular the invention relates to an information holding device for use with pets.
2. Description of the Related Technology
Responsible owners of pets, and particularly those pets that are likely to stray outdoors, will typically want to provide some form of identification carried by the pet that identifies the name and address of the pet and/or pet's owner. Typically this information is placed on the pet's collar in a permanent fashion with a hanging tag. In the event that the tag falls off the collar and is lost, which frequently occurs, the tag is rendered useless. Furthermore, in the event the pet and/or pet owner's address or information changes the hanging tag becomes useless, as it is usually impractical to alter.
In the past, some pet collars have been developed in order to counter this problem. U.S. Pat. No. 4,137,660 to Dettmann et al. discloses a pet collar with a tag holder. Identification information is placed under a transparent plastic window that is lifted in order to place the identification information underneath. Although able to change identification information on the collar itself, an owner is not able to transfer that information to another collar unless that collar is similarly equipped.
U.S. Pat. No. 4,178,879 to Cunningham also discloses a collar with a transparent window. The identification information is slid underneath a transparent plastic window on the collar. Although able to change identification information, an owner is not able to place to the information on any available collar.
Therefore, there exists a need for providing a dog collar with the ability to change identification information on the collar along with the capability of being able to transfer existing identification information to different collars.

Pet product with device for holding information article


The invention relates to a process for producing outer membrane proteins of gram-negative bacteria by gram-positive host cells. To this end, a gene structure containing a gene coded for an outer membrane protein is constructed; in front of this gene there is a pro-gene sequence which codes for a propeptide of an export protein of a gram-positive bacterium. In front of the pro-gene sequence there is a pre-gene sequence which codes for a signal peptide of an export protein of a gram-positive bacterium. After the cloning of a gene structure thus constructed into a vector and transformation into a gram-positive bacterium, the outer membrane protein is expressed with a signal peptide and propeptide, transported through the membrane of the gram-positive host cell and released into the test of the culture.

Proteins from the outer membrane of Gram-negative bacteria are primarily exposed on the cell surface of these bacteria and in the case of pathogenic bacteria serve as possible attack points for the recognition of the bacteria by the immune system of the infected host.
It is thus desirable, with the aid of purified outer membrane proteins by inoculation to achieve protection of the host against the corresponding bacterium (Smyth, C. J. (1985) Immunology of outer membrane proteins of Gram-negative bacteria. In: Immunology of the Bacterial Cell Envelope (Stewart-Tull, D. E. S., Davies, M.; eds.) John Wiley and Sons Ltd. Pp. 177-201). A further possible use of isolated membrane proteins is their use as antigen in diagnostic test systems.
One way for recovery of the proteins is their isolation from the outer membrane Gram-negative bacteria. It is, however, problematic in that case that the outer membrane proteins have a high affinity to the lipopolysaccharide localized in the outer membrane so that the proteins can only be separated with difficulty from these endotoxins (Nikaido, H., Vaara M. (1985) Molecular basis of bacterial outer membrane permeability. Microbio). Rev. 49, 1-32). It is desirable to provide a way of producing outer membrane proteins which utilizes Gram-positive bacteria for their synthesis and which have an outer membrane with no lipopolysaccharide. One can expect that with these organisms endotoxin free outer membrane proteins can be recovered.
There are already different outer membrane proteins of Gram-negative bacteria (e.g. OmpA, OmpF) which are expressed intracellularly in the Gram-positive bacterium Bacillus subtilis (Puohiniemi, R., Butcher, S., Tarkka, E., Sarvas, M., (1991) High level production of Escherichia coli outer membrane proteins OmpA and OmpF intracellularly in Bacillus subtilis. FEMS Micro-biol. Lett. 83, 29-34). It has also been sought to export outer membrane proteins through the cytoplasmic membrane of Gram-positive bacteria for which secretory proteins are used for channeling in the exportation step and are necessary for the subsequent membrane transport and are fused to the outer membrane proteins: for example, a fusion of the membrane protein with the 298 aminoacid secretory protein .alpha.-amylase Bacillus amyloliquefacines is effected. In all of these cases, the expected secretion or transport of such fused membrane proteins is not found to occur (Kallio, P., Simonen, M., Pavla, I., Sarvas, M. (1986), Synthesis of OmpA protein of Escherichia coli K12 in Bacillus subtilis, J. Gen. Microbiol. 132, 677-678; Puohiniemi, R., Simonen, M., Muttilainen, S., Himanen, J.-P., Sarvas, M. (1992), Secretion of the Escherichia coli outer membrane proteins OmpA and OmpF in Bacillus subtilis is blocked at an early intracellular step., Mol. Microbiol. 6, 981-990; Simonen, M., Tarkka, E., Puohiniemi, R., Sarvas, M. (1992), Incompatibility of outer membrane proteins OmpA and OmpF of Escherichia coli with secretion in Bacillus subtilis: Fusions with secretable peptides, FEMS (Microbiol. Lett. 100, 233-242). By contrast, one finds instead, after expression, an outer membrane protein of Escherichia coli together with the authentic Gram-negative signal peptide in Bacillus subtilis, a transport through its cytoplasmic membrane but with the protein remaining cell associated, i.e. not secreted into the culture medium (Meens, J., Frings, E., Klose, M., Freudi, R. (1993), An outer membrane protein (OmpA) of Escherichia coli can be translocated across the cytoplasmic membrane of bacillus subtilis, Mol. Microbiol. 9, 847-855).

Secretion of outer membrane proteins of gram-negative bacteria by means of gram-positive host organisms


An input section of an incubator accepts, from a user, a first input selecting a specified incubation container which registers an observing schedule, and a second input specifying an imaging condition of the specified incubation container in an observing sequence. A calculating section calculates, according to the above-mentioned imaging condition, an observing duration of the specified incubation container from a first data relating to a carrying period of an incubation container and a second data with regard to an imaging duration. A schedule management section extracts, based on a schedule data, a registrable time zone in which an observing sequence of the specified incubation container can be executed without overlapping with previously registered observing schedules, and outputs to display the registrable time zone for presentation to the user.

1. Field
The present invention relates to an incubator comprising a temperature-controlled room which can maintain the environment condition suitable for incubating samples, and peripheral technology thereof.
2. Description of the Related Art
Incubators comprising a temperature-controlled room are generally used to incubate samples such as various microorganisms or cells. In such a temperature-controlled room, it is common to simultaneously incubate samples in a plurality of incubation containers.
On the other hand, it has been proposed to provide the incubator with a function of automatically observing the sample within the incubation container. For example, Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2006-11415) discloses an arrangement of an incubation microscope which automatically executes time lapse observing of samples.
When automating the observation of samples in the incubator, it becomes very important to control the observing schedule. Particularly, overlap of observing schedules for a plurality of incubation containers may raise the possibility that samples can not be recorded with the time zone and number of times of observations desired by the user, whereby availability of the device substantially decreases. The above-mentioned Patent Document 1 has not sufficiently given consideration to prevent overlap of observing schedules, which leaves room for improvement at this point.

This patent is subject to a terminal disclaimer.

Incubator, schedule management method, and program


A variable torque device for maintaining constant tension in a web of material as the web is unwound from a supply roll. The variable torque device includes a lead screw attached to the shaft of the supply roll via an appropriate gear ratio. A coil spring is located between a hub on the lead screw and a set of rings and friction pads. As the lead screw rotates, the hub translates, thus changing the displacement of the coil spring, which in turn changes the loading of the rings and friction pads. With a full supply roll the coil spring is compressed so as to create an amount of torque to create the desired web tension. As the supply roll unwinds, the rotation of the lead screw translates the hub to expand the coil spring, reducing the torque and maintaining the web tension constant.

Many applications and/or processes involve the unwinding of material, in the form of a web, from a roll as the material is subsequently used in the application or process. Subsequent to unwinding, the material may be used in the process and then wound onto a take-up roll, or it may be cut or slit into parts to be consumed in the process. Materials used in these processes may have widely varying physical properties, such as flexibility, breaking strength, elasticity, etc. Depending upon the physical properties of the material and/or the nature of the subsequent process, it may be important to maintain the tension in the material constant or at least within a narrow range, as the material is being unwound from the roll. As anyone skilled in the art will recognize, if the torque exerted on the roll is constant, the tension in the material will increase as it is unwound and the diameter of the roll decreases.
An example of such a process is a web type release fluid applicator for fusers in electrostatographic reproduction apparatus such as copier/duplicators, printers, or the like. In electrostatographic reproduction apparatus a latent image charge pattern is formed on a uniformly charged charge-retentive or photoconductive member having dielectric characteristics. Pigmented marking particles are attracted to the latent image charge pattern to develop such image on the photoconductive member. A receiver member, such as a sheet of paper, transparency, or other medium, is then brought into contact with the photoconductive member, and an electric field applied to transfer the marking particle developed image to the receiver member from the photoconductive member. After transfer, the receiver member bearing the transferred image is transported away from the photoconductive member, and the image is fixed (fused) to the receiver member by heat and pressure to form a permanent reproduction thereon.
One type of fuser assembly for typical electrostatographic reproduction apparatus includes at least one heated roller, having an aluminum core and an elastomeric cover layer, and at least one pressure roller in nip relation with the heated roller. The fuser assembly rollers are rotated to transport a receiver member, bearing a marking particle image, through the nip between the rollers. The pigmented marking particles of the transferred image on the surface of the receiver member soften and become tacky in the heat. Under the pressure, the softened tacky marking particles attach to each other and are partially imbibed into the interstices of the fibers at the surface of the receiver member. Accordingly, upon cooling, the marking particle image is permanently fixed to the receiver member.
With roller fuser assemblies, it is common practice to use release fluids, such as silicone oil for example, applied to the fuser roller surface to improve the release of image-carrying receiver members from the fuser roller. The most common types of release fluid applicators or oilers are a rotating wick roller, a donor/metering roller, an oil impregnated pad or roller, an oil impregnated web, or variations or combinations of the above. In a release oil applicator utilizing an oil-impregnated web, the web is, for example, formed as a porous membrane capable of retaining release oil. The oil-impregnated web extends from a supply roll to a take-up roll. The portion of the oil impregnated web between the supply roll and the take-up roll is directed about intermediate rollers, at least one of which is a back-up roller urging the oil-impregnated web into contact with the heated fuser roller. Another of the intermediate rollers and/or the take-up roller is driven for pulling the oil-impregnated web from the supply roll onto the take-up roll.
As explained above, if the torque applied to the supply roll is maintained constant, the tension in the oil impregnated web will increase as the diameter of the supply roll decreases due to unwinding of the oil impregnated web. As the tension increases the oil impregnated web can become distorted, thus affecting the uniformity and rate of oil delivery to the heated fuser roller. Non-uniform and variable rate of oil delivery to the heated fuser roller can cause unacceptable image quality defects in the fused marking particle image on the receiver member.

Variable torque device for maintaining constant web tension


A bandwidth efficient and robust timing synchronization approach in an ad-hoc network is provided by a mobile ad-hoc network including at least one group of mobile nodes having at least one timing reference (TR) node. Mobile nodes include a controller and a wireless communications device cooperating therewith to generate and transmit timing synchronization beacons having a respective hop count indicating a number of hops to the at least one timing reference node, receive timing synchronization beacons from neighboring nodes, and synchronize node communication timing with neighboring nodes based upon the number of hops to the at least one timing reference node. The timing reference node may cooperate with the other mobile nodes based upon a timing source priority tree including levels defined by hop counts. The timing reference node is at a starting level of the timing source priority tree. The other nodes are at a higher level of the timing source priority tree than the starting level and correspond to the number of hops to the at least one timing reference node.

Wireless networks have experienced increased development in the past decade. One of the most rapidly developing areas is mobile ad-hoc networks. Physically, a mobile ad-hoc network includes a number of geographically-distributed, potentially mobile nodes sharing a common radio channel. Compared with other types of networks, such as cellular networks or satellite networks the most distinctive feature of mobile ad-hoc networks is the lack of any fixed infrastructure. The network may be formed of mobile nodes only, and a network is created "on the fly" as the nodes transmit with each other. The network does not depend on a particular node and dynamically adjusts as some nodes join or others leave the network.
The standards governing Wireless Local Area Networks (WLANs) networking products are defined by a suite of specifications issued by the IEEE and known as the IEEE 802.11 standard, incorporated herein by reference in their entirety. The standards define the operation of both the radio PHY layer and the MAC layer including a synchronization mechanism. The synchronization mechanism is used to provide a uniform time base.
For example, a timing synchronization function is operative to keep the timers of all the nodes in the same basic service set (BSS) synchronized. Each node maintains its own local timer. In a conventional WLAN infrastructure network, the access point is the timing master and is operative to implement the timing synchronization function. The access point periodically transmits special frames called beacons that contain a copy of its timing synchronization function timer. The beacons are used by the other nodes to synchronize to the access point. A node always accepts the timing information received in a beacon from the access point servicing its BSS. If the timer of a node is different from the timestamp in the received beacon, the receiving node sets its local timer to the received timestamp value.
For ad-hoc networks, the timing synchronization is typically implemented using a distributed algorithm that is performed by the member nodes. Each node transmits beacons in accordance with an algorithm defined in the 802.11 standard. Each node adopts the timing received from any beacon or probe response that has a timing synchronization function value later than its own timer. Nodes expect to receive beacons at a nominal rate. The interval between beacon transmissions is defined by beacon period parameter of the node. A node sending a beacon sets the value of the timestamp to be equal to the value of the timing synchronization function timer of the node at the time that the first bit of the timestamp is transmitted to the PHY plus the transmitting delays of the node through its local PHY from the MAC-PHY interface to its interface with the wireless medium (i.e. antenna, etc.).
Time Division Multiple Access (TDMA) based ad-hoc networks are prone to synchronization issues due to node movement, radio clock drifting, merging of groups of nodes with different timing references. A timing reference is the beginning time of a common frame. There are many other causes for network synchronization errors.
Various problems exist with correcting timing reference errors. For example, a node can broadcast a timing reference packet to correct the timing errors in the network. But it may take sometime or require continuous flooding of the timing reference information for the timing reference node to know about the error conditions.
Current approaches include flooding the network with a Timing Reference Packet (TRP) but bandwidth consumption is a concern. If the network maintains a network clock then the TRP uses a time stamp to represent the correct timing reference. For example, an 802.11 type of network keeps a common network clock. If there are unstable links, not every node could hear the single flooding of the timing reference packet, and flooding may have to be done multiple times, or periodically. The timing reference packet has to be sent periodically due to clock drifting. If a network clock is not maintained (identity of the timing reference but not the reference time is distributed) then the TRP may contain a unique packet ID, so that whichever node has received the TRP can derive the correct identification of the timing reference node. The timing reference node is notified if a synchronization error is detected or the TRP is periodically flooded. However, a timing reference ambiguity can persist for some time.
Another conventional approach is Ad-hoc Extensions to the 802.15.2 MAC Protocol (developed by Winlab, Rutgers university). The group uses 2 keys in a beacon. A key is similar to the group ID. It is used to indicate synchronization status and membership. Either one of the two can be used to identify the group. The two keys shared by all member nodes have different expiration time stamps. They will be regenerated and re-distributed to all members, if expired. If the group is separated longer than the key expiration period, the current keys circulated in each group will be different. When the sub-groups merge, they will go through the normally required re-synchronization process. However, it will be immediately evident to all nodes in each group that there are two timing reference nodes.
This approach can be complicated when the groups are merging at the same moment as the new keys are being generated and re-distributed in ether, or both groups. Another disadvantage of this approach is the bandwidth consumption by the two keys. In an HP-NET, a key of 20 to 30 bits would consume a significant amount of the bandwidth allocated by each node to network control tasks.
Many references relate to the synchronization of devices in hierarchical wireless networks, where one or several synchronized masters operate as timeservers. U.S. Patent Application Serial No. 20040190487, entitled "Method For Synchronizing A Control Channel To A Working Channel", filed on Mar. 31, 2003, for example, relates to a method for synchronizing a control channel to a working channel. Moreover, U.S. Pat. No. 6,792,247 relates to a method for synchronizing reception in wireless networks, in which a synchronization packet of a special format is transmitted before a data packet is transmitted. U.S. Pat. No. 6,785,253 and U.S. Pat. No. 6,622,022 also disclose methods for synchronizing hierarchical wireless networks wherein at least one node is selected as the central transfer node or as the main network node which is responsible for providing frame synchronization services. Moreover, U.S. Pat. No. 6,546,026 relates to a method for improving the time synchronization in wireless applications (e.g., TDMA).
Methods for synchronizing cellular wireless networks using GPS timing signals can also be found in U.S. Pat. No. 6,542,754 and U.S. Pat. No. 6,538,600. Moreover, U.S. Pat. No. 6,466,608 relates to a synchronization method that requires defining a hierarchical structure of the network, wherein the synchronization process is controlled by assigned master nodes. Moreover, U.S. Pat. No. 5,812,547 relates to a method for transmitting data packets in a wireless network, without dependence on fixed time slot or a central timing mechanism.
U.S. Pat. No. 6,594,273 relates to a method for communicating in an ad-hoc multihopping network, wherein the network includes active and passive terminals, and wherein only the active terminals participate in routing and synchronization. U.S. Pat. No. 6,807,165 and U.S. Pat. No. 5,699,388 present methods using a unique time source and propagating the synchronization in the network from upstream to downstream terminals. Moreover, U.S. Patent Application Serial No. 20040005902, entitled "System and method for correcting the clock drift and maintaining the synchronization of low quality clocks in wireless networks", filed Jul. 5, 2002, relates to a method that allows synchronization of terminals at any precision, using a reference clock that operates as a network master.

Synchronization and timing source priority in an ad-hoc network


A coffee filter roll is disclosed herein. The coffee filter roll includes a plurality of coffee filters successively arranged in a roll configuration, each of the plurality of coffee filters being detachably coupled to one another and including a plurality of fold lines configured to facilitate an insertion of each of the plurality of coffee filters into a coffee filter basket of a coffee maker; and a plurality of lines of weakness, each of the plurality of lines of weakness being disposed between adjacent coffee filters in the coffee filter roll. Each coffee filter is configured to be separated from the coffee filter roll by tearing the coffee filter being removed from the adjacent coffee filter in the coffee filter roll along at least one of the plurality of lines of weakness. A coffee filter dispensing system and a method of dispensing rolled coffee filters is also disclosed herein.

1. Field of the Invention
The invention generally relates to coffee filters. More particularly, the invention relates to coffee filters that are in a roll configuration, a system for dispensing rolled filters, and a method of dispensing rolled coffee filters.
2. Background and Description of Related Art
Traditional coffee filters are sold in stacks or sleeves, making them difficult to separate when making coffee. People may accidently use two or three filters at one time, which can be wasteful and can cause water to flow over the sides of a coffeepot and make a mess. Filters are also packaged in plastic, which can be difficult to open, especially for elderly people or people with disabilities. Additionally, filters are typically stored unprotected in a cabinet or drawer, which can be unsanitary.
Therefore, what is needed is a coffee filter roll and coffee filter dispensing system using the same that provides people with quick and convenient access to coffee filters, and ensures only one filter is used at a time. Moreover, a coffee filter roll and coffee filter dispensing system is needed that protects the coffee filters from contaminants while stored away, and reduces the overall amount of time it takes to make coffee. Furthermore, there is a need for a coffee filter roll and coffee filter dispensing system that is ideal for use in both residential and commercial settings. There is also a need for a method of dispensing rolled coffee filters that has the abovementioned attributes.

Coffee filter roll, coffee filter dispensing system, and a method of dispensing rolled coffee filters


A method of real-time rotor fault detection includes measuring a set of loads to obtain measured signals and virtually monitoring the set of loads to obtain estimated signals. The estimated signals are subtracted from the measured signals to obtain residuals and the residuals are compared to a categorical model. A categorical output representative of a rotor fault is identified within the categorical model.

The present disclosure relates to a health monitoring system, and more particularly to a real-time fault detection and isolation system.
Helicopter rotor systems may be subject to a number of fault types such as imbalance, track splits, cracks, defects, and freeplay or friction in the pitch control systems, lag systems and flap systems. Early detection and diagnoses of these fault conditions facilitates the reduction of aircraft maintenance costs and further enhances flight safety.
Under a fixed flight condition and in the absence of other disturbances, detection and diagnoses of fault types may be determined by measurement of rotor hub loads. However, nominal hub loads are a strong function of aircraft flight condition, pilot inputs, and other disturbances. The magnitude of hub load changes from flight conditions, pilot inputs, and disturbances is significant enough to effectively obscure the effect of rotor system faults on hub loads.

Rotor system health monitoring using shaft load measurements and virtual monitoring of loads


An improved wheel assembly comprises a caster swivel post that is adapted to pivot about a pivot axis transverse to the caster swivel post. A caster fork is supported for rotation relative to the caster swivel post and rotatably supports a caster wheel. The caster swivel post is adapted selectively pivot about the pivot axis that is transverse to the caster swivel post or be held in a substantially fixed position. A setscrew can be threadable into an upper end of a pivot nut to hold the pivot nut and thus the caster swivel post in a fixed position within the housing.

This invention relates in general to improvements in wheel assemblies of the type used with wheelchairs and other devices. More particularly, this invention relates to an improved caster wheel assembly having an adjustable caster swivel post for varying the angle of the caster swivel post to ensure that the caster swivel post remains in a vertical orientation. Moreover, this invention relates to an improved rear wheel assembly having an adjustable axle for varying the camber angle of the axle.
Caster wheel assemblies in general are well known in the art for use with many different types of castered devices. Such caster wheel assemblies are commonly employed as the front wheels in a typical wheelchair. Each caster wheel assembly typically includes a caster fork, which rotatably supports a relatively small diameter caster wheel, and which further includes a generally upright caster swivel post captured by appropriate caster post bearings for rotation about a swivel axis within a fixed cylindrical housing. The fixed housing is adapted in turn for mounting onto frame components of the wheelchair, or other castered device. Such caster wheel assemblies beneficially provide a high degree of turning maneuverability.
The caster swivel post defines a vertically oriented axis about which the caster fork rotates. The caster post bearings are typically used to provide a smooth, frictionless pivot. The caster wheel is rotatably supported by the caster fork via a caster wheel axle, which is situated rearward with respect to the caster swivel post. This ensures that the caster wheel axle is always trailing the caster swivel post in the direction of travel. The rearward offset distance of the caster wheel axle with respect to the caster swivel post is commonly referred to as the "rake". The caster swivel post must be oriented vertically to ensure that the caster wheel remains in contact with a supporting surface as the caster fork pivots about the caster swivel post. This vertical orientation ensures that the caster wheel will not lift off the supporting surface while turning.
Wheelchairs and other castered devices typically incorporate a number of adjustments, including wheel height adjustment, wheel camber adjustment, and wheel size adjustment. Such adjustments are common with regard to the rear wheels of the wheelchair to allow a wheelchair occupant to customize the wheelchair to his or her anthropometry or driving conditions. When any of these adjustments are made, the angle of the caster swivel post changes and must also be adjusted to ensure that the caster swivel post remains vertical. Various means have been used to achieve caster swivel post angle adjustment, and are currently available on the market. Such means are typically bulky, heavy, and cumbersome for the user to adjust.
What is needed is an improved adjustable wheel assembly having a unique means for providing adjustability and that is a very compact, lightweight, and easy for the user to adjust.


In one embodiment, a circuit comprises a first switching transistor and a second switching transistor. The first switching transistor and the second switching transistor are coupled in series between an input voltage and ground and having a common node therebetween to provide a switching output. A first switching circuit selective couples a gate of the first switching transistor to the input voltage and a first mid-level voltage supply. A second switching circuit selectively couples a gate of the second switching transistor to a second mid-level voltage supply and ground. A charge-recycling circuit is coupled to the gate of the first switching transistor, the gate of the second switching transistor, the first mid-level voltage supply, and the second mid-level voltage supply to selectively recycle charge between the first mid-level voltage supply and the second mid-level voltage supply.

The disclosure relates to charge-recycling circuits, and in particular, to charge-recycling circuits including switching power stages with floating rails.
Unless otherwise indicated herein, the approaches described in this section are not admitted to be prior art by inclusion in this section.
Power stages are core blocks of switched-mode power supplies and are used to change the current and power flow during each phase of operation. The internal loss of a power stage is a critical design parameter of a power stage and should be minimized to improve the overall power conversion efficiency.
It is very common to use regulated mid-rails (auxiliary rails) to drive each power switch of the power stage to optimize the over-drive voltage (or gate-source voltage VGS) of switches. The mid-rails are often generated and regulated using low dropout regulators (LDOs). However, LDOs suffer from poor efficiency especially when the voltage drop across the pass device is high.

Charge-recycling circuits including switching power stages with floating rails


The present invention provides a catalyst for reduction of nitrogen oxides represented by the formula (A.sub.a O.sub.x.B.sub.b O.sub.y).(C.sub.c O.sub.z.C'.sub.c' O.sub.z')/S which is produced by supporting mixed metal oxides represented by the formula (A.sub.z O.sub.x.B.sub.b O.sub.y).(C.sub.c O.sub.z.C'.sub.c' O.sub.z') in amorphous state on aluminum or silicon-containing support at calcination temperature of 400.degree. to 700.degree. C. in a molar ratio of 0.01:1 to 5:1, and. a method for removing nitrogen oxides through selective catalytic reduction which comprises converting 50 to 50,000 ppm of nitrogen oxides in exhaust gas from automobile or from fixed source such as plant turbine and boiler, and other industry in a state of having 0.1 to 20% of excessive oxygen over (A.sub.a O.sub.x.B.sub.b O.sub.y).(C.sub.c O.sub.z.C'.sub.c' O.sub.z')/S catalyst by using 100 to 100,000 ppm of hydrocarbon reducing agent having 1 to 5 carbons under the reaction condition of 200.degree. to 800.degree. C. of reaction temperature, 1 to 10 atmosphere of reaction pressure and 1000 to 100,000/hour of space velocity into nitrogen in which. A and B are lanthanide metals, such as lanthanum, cerium, praseodymium or neodymium, and alkali metals or alkaline earth metals, such as sodium, potassium, rubidium, cesium, magnesium, calcium, strontium or barium,. C and C' are transition metals of the first period, such as cobalt, copper, nickel, manganese, iron, vanadium, titanium, chromium and zinc, and noble metals, such as platinum, rhodium, iridium, ruthenium, rhenium, palladium and silver,. a, b, c and c' have stoichiometrically 0 to 1, provided with a+b=1, c+c'=1 and is in the range of 0.1-3.0:1.0, and. S is aluminum or silicon-containing support, and is zeolite, silica, alumina or silica-alumina.

Nitrogen oxides (NO.sub.x) meaning nitrogen monoxide, nitrogen dioxide and nitrous oxide are environmental contaminant materials like carbon oxides and sulfur oxides. Nitrous oxide is not very toxic, but it is one of major contaminants causing global warming like carbon dioxide. Nitrogen monoxide is a major component of nitrogen oxides in exhaust gas, and can be easily converted into nitrogen dioxide even at room temperature when it is discharged into air. Both nitrogen monoxide and nitrogen dioxide are carcinogenic materials. They cause serious air pollution and acid rain like sulfur oxides. The discharge of nitrogen oxides are caused mostly by reaction of nitrogen and oxygen in air during high temperature combustion and combustion of nitrogen compound contained in fuel. There is, therefore, a need to provide a technique of removing nitrogen oxides by treating exhaust gas in addition to controlling the generation of nitrogen oxides through combustion control.
The technique of removing nitrogen oxides is largely divided into two groups depending on their use of catalyst. When a catalyst is used, the technique is divided into a method using reducing agent and a method of decomposing directly on a catalyst without using reducing agent. A method which directly decompose nitrogen oxides in exhaust gas on catalyst into nitrogen and oxygen is referred since nitrogen oxides are unstable thermodynamically as compared to nitrogen and oxygen. However, a suitable catalyst for the method is not found since the method has problems in that it requires high reaction temperature and the activity of the catalyst decreases easily.
The technique of selective catalytic reduction of nitrogen oxides has come to employed since the treatment with ammonia as a reducing agent was practically used and the application of the technique has rapidly increased. Taking into account the fact that the discharge of various environmental contaminating exhaust gas will be severely regulated in advanced nations, it is likely hay the demand of the technique will increase largely. However, the conventional reduction method using ammonia as a selective reducing agent has some problems in that in addition to the problems of difficulty of transport and charge and high equipment maintenance cost due to the corrosion property of ammonia, unreacted ammonia is drawn off into the air and thus cause secondary air pollution. Owing to those drawbacks, recently the research has been devoted to substitution of carbon containing compounds, such as hydrocarbon, methanol or ethanol for a reducing agent.
In order to develop reduction catalysts which directly decompose nitrogen monoxide or in available for selective contact reducing agent, many researches have been investigated concerning metal or metal oxide catalyst of platinum group since 1970. When air to fuel ratio of automobile is stoichiometric, three-way catalyst of platinum-palladium-rhodium is able to convert carbon monoxide, hydrocarbon and nitrogen oxides which are contaminants of exhaust gas to innoxious gas by more than 90%. However, in the case that exhaust gas is dilute under excessive oxygen as in lean burn gasoline engine or diesel engine, the three-way catalyst can not act as reduction catalyst for nitrogen oxides but only as oxidation catalyst. For this reason, copper ion exchanged Cu--ZSM-5 zeolite and various metal oxides catalyst have been developed as catalysts for removing nitrogen oxides for substituting for three-way catalyst of platinum group. According to the reports made until now, copper ion exchanged Cu--ZSM-5 zeolite are said to be the most effective catalyst for converting nitrogen oxides into nitrogen and oxygen.
Japanese Patent No. 03 86 213 according to Hamada et al., suggested the use of various zeolites including modernite, ferrierite, L type and ZSM-5 as catalysts for converting nitrogen oxides into innoxious gas under excessive oxygen. The catalyst shows very high activity on direct decomposition of nitrogen oxides. Iwamoto et al. suggested Cu--ZSM-5 zeolite which is exchanged by copper ion by more than 100% in over pH 6 in Japanese Patent 03 101 837 had excellent effect on converting nitrogen oxides. Many studies have confirmed the possibility of using Cu--ZSM-5 zeolite as direct decomposition catalyst for nitrogen oxides. However, it is sensitive to sulfur oxides and steam, and thus easily lose activity. The activity can be reduced considerably under excessive oxygen and at high space velocity as well. To solve such problems relating to Cu--ZSM-5 zeolite, Iwamoto and Hamada (Shokubai, 32 430 (1990), Appl. Catal., 64, L1 (1990)), and Held et al., (SAE Paper 900496 (1990)) proposed selective catalytic reduction of nitrogen oxides by utilizing hydrocarbon contained in exhaust gas.
Zeolite catalyst systems exchanged by transition metal ion other than copper ion are Co--ZSM-5 disclosed in Appl. Catal. B. 1, L31 (1992) according to Arm et al. (USA) and Ga--ZSM-5 in Japanese Patent 05 212 288. These catalysts showed very high reduction activity of nitrogen oxides due to oxidation of hydrocarbon even in the presence of excessive oxygen in 10% or so and in methane which is nonselective reducing agent. Yokoyama et al. also suggested several kinds of catalyst systems including Ce--ZSM-5 overcome the drawbacks of Cu--ZSM-5 catalyst (Shokubai, 35, 122 (1993).
As a compound having direct decomposition activity of nitrogen oxides, there are supported noble metal catalyst (typically, platinum/alumina), transition metal oxides (typically, cobalt oxides CO.sub.3 O.sub.4), mixed metal oxides (typically, perovskite oxides) and transition metal-exchanged ZSM-5 zeolites (typically, Cu--ZSM-5). Among them, metal oxides or complex thereof are known to have high decomposition activity of nitrogen oxides at high temperature, but to have drastically decreased decomposition activity of NO.sub.x in the presence of excessive oxygen. There are little reports on selective catalytic reduction of mixed metal oxides using hydrocarbon as a reducing agent in the presence of excessive oxygen. Shin et al. reported decomposition activity of SrFeO.sub.3-x having perovskite structure with regard to nitrogen oxides in Mat. Res. Bull., 14, 133 (1979). Teraoka et al. reported decomposition activity of lanthanum-strontium-cobalt (manganese, iron, copper) with regard to NO.sub.x showed 30 to 75% of NO.sub.x conversion at high temperature of 700.degree. to 800.degree. C. (Chem. Lett., 1 (1990)). Shimada et al. reported that itrium-barium-copper oxide and itrium-barium-copper/magnesia showed 73% of decomposition activity at a temperature of over 600.degree. C. (Chem. Lett., 1 (1988)). However, Iwamoto and Hamada et al. also found that the activity of SrFeO.sub.3-x oxide, lanthanum-cobalt oxide and itrium-barium-copper oxide was reduced drastically in the presence of 5% oxygen, which resulted from low surface area of the those oxides (Catal. Today, 10, 57 (1991)). Examples of utilizing mixed oxide of perovskite type for the treatment of nitrogen oxides were disclosed in Japanese Patent 05 38 435. In this patent, as catalysts for removing air pollutants containing hydrocarbon, carbon monoxide and nitrogen oxides, mixed oxides including rare earth elements and oxides thereof, alumina, zirconia, iron oxides, bismuth oxides, complex perovskite containing more than one of noble metal were suggested, which were known to have heat resistance and catalyst stability.
Mixed metal oxides with perovskite structure have some drawbacks, for example, they show the decomposition activity for NO.sub.x only at high temperature, and their activity is drastically reduced in the presence of oxygen.
Therefore, the present inventors have made extensive studies to solve the problems relating to the mixed metal oxides with perovskite structure. As a result the present inventors have now found that the mixed metal oxides/zeolite catalyst produced by supporting mixed metal oxides on ZSM-5 zeolite support can be used in selective catalytic reduction of NO.sub.x using hydrocarbon as a reducing agent in oxygen excess and thus the activity of selective catalytic reduction of that catalyst can be maximized at low temperature less than 400.degree. C.

Method for removing nitrogen oxides in exhaust gas by selective catalytic reduction and catalyst for reduction of nitrogen oxides

Korea Research Institute of Chemical Technology


An electron emission device and/or display using the same includes a beam-focusing structure. The beam-focusing structure has a first insulating layer formed on a plate. The first insulating layer has a thickness, and is formed with a first hole. A first electrode is formed on the first insulating layer and extending into the first hole. An emission portion is formed in the first hole and connected to the first electrode. A second insulating layer is formed on the first electrode and is also formed with a second hole through which the emission portion is at least partially exposed. A second electrode is formed on the second insulating layer. In the electron emission device and/or the display, an electric field between the first electrode and the second electrode causes the emission portion to emit an electron beam and focuses the electron beam from the emission portion.

1. Field of the Invention
The present invention relates to an electron emission device, and more particularly, to an electron emission device and an electron emission display having a beam-focusing structure using an insulating layer.
2. Discussion of Related Art
Generally, an electron emission device can be classified into a hot cathode-type and a cold cathode-type. The hot cathode-type and the cold cathode-type employ a hot cathode and a cold cathode as an electron emission portion, respectively.
Also, a cold cathode-type electron emission device can have a structure such as a field emitter array (FEA), a surface conduction emitter (SCE), a metal insulator metal (MIM), a metal insulator semiconductor (MIS), a ballistic electron surface emitting (BSE), etc.
The electron emission device having the FEA structure is based on a principle that when a material having a low work function and/or a high beta(β)-function is used as an electron emission portion in a vacuum, electrons are easily emitted from the material due to an electric field difference. Such electron emission device having the FEA structure employs a tip structure mainly containing molybdenum (Mo), silicon (Si), a carbon material (e.g., graphite, diamond-like carbon (DLC), etc.), and/or a nano material (e.g., a nanotube, a nanowire, etc.) as the electron emission portion.
The electron emission device having the SCE structure is provided with an electron emission part in which a first electrode and a second electrode opposing each other are formed on a first plate, and a conductive layer is formed between the first electrode and the second electrode. The conductive layer is formed with a minute crack or gap, thereby forming the electron emission part. Such electron emission device is based on a principle that the electron emission part formed by the minute crack or gap emits electrons when electric current flows through a surface of the conductive layer by applying voltage to the first and second electrodes.
The electron emission device having the MIM or MIS structure includes an electron emission portion having a metal-insulator-metal structure or a metal-insulator-semiconductor structure, and is based on a principle that electrons are emitted from the metal or the semiconductor of high-electric potential to the metal of low-electric potential when a voltage is applied between the metal and the metal or between the metal and the semiconductor.
The electron emission device having the BSE structure is based on a principle that electrons travel without sputtering when the size of a semiconductor is smaller than a mean free path of the electrons contained in the semiconductor. Such electron emission device includes an electron supplying layer made of a metal or a semiconductor and formed on an ohmic electrode, an insulator formed on the electron supplying layer, and a thin metal layer formed on the insulator, so that the electrons are emitted when a voltage is applied between the ohmic electrode and the thin metal layer.
The foregoing electron emission devices are employed in electron emission displays, backlights, lithography electron beams, etc.
In the aforementioned electron emission devices, the electron beam emitted from the electron emission portion spreads in a voltage-applied direction. Therefore, there is a need for a focusing electrode to focus the electron beam. An example of an electron emission device with the focusing electrode is disclosed in Korean Patent Publication No. 2002-32208. Hereinafter, the conventional electron emission device with the focusing electrode will be described with reference to FIGS. 1 and 2.
FIG. 1 is a schematic plan view of a conventional electron emission device with a horizontal focusing electrode.
As shown therein, the conventional electron emission device includes a plurality of micro-tips 1 respectively formed inside a plurality of gate holes 2, a gate electrode 3 formed above the micro-tips 1 and determining an emitting direction of electrons emitted from each micro-tip 1, and a focusing electrode 4 to focus the electrons emitted from the micro-tips 1.
In the conventional electron emission device, to enhance a focusing effect, a distance between at least one of the micro-tips 1 used as an emitter and the gate electrode 3 should be short, and, at the same time, a distance between the gate electrode 3 and the focusing electrode 4 should also be short. Because of this, the fabricating process for the conventional electron emission device is difficult. Also, when the focusing electrode 4 is horizontally arranged, the number of emitters per unit surface area is limited.
FIG. 2 is a sectional view of a conventional electron emission device with a vertical focusing electrode.
As shown in FIG. 2, the conventional electron emission device includes a plate 202, a first insulator 203, a gate electrode 204, an emitter 205, a cold cathode 206, a second insulator 207, a focusing electrode 208 and a metal mesh 210. In this electron emission device, in order to focus an electron beam from the emitter 205, a voltage of −40V is applied to the focusing electrode 208 and a voltage of 80V is applied to the gate electrode 204. Here, the voltage applied to the gate electrode 204 serves to control the amount of beam current.
Such conventional electron emission device with the vertical focusing electrode is excellent in focusing the electron beam, but has a complicated fabricating process because the insulator formed on the gate electrode should be thick with a thickness of a few μm to a few hundreds μm, thereby lowering a yield thereof.

Electron emission device and electron emission display having beam-focusing structure using insulating layer


An ultraviolet area sterilizer or disinfector is incorporated into a building structure where concern exists regarding the presence of pathogenic bacteria on environmental surfaces. Ultraviolet C (UV-C) generators generate UV-C that is directed to architectural partitions of an enclosed area. The architectural partitions reflect UV-C to kill pathogens in the enclosed area. The device transmits a calculated dose of UV-C from a fixture mounted to an architectural partition in the enclosed area. Once an effective cumulative dose of UV-C has been reflected to radiation sensors, as measured by the sensors, the device shuts down.

Nosocomial, or hospital acquired, infections are common, costly, and sometimes lethal. A recent review of such infections in the cardiac surgery unit of a major hospital revealed a nosocomial infection rate of 27.3% that more than doubled the mortality rate for afflicted patients. The nature of bacteria acquired in the hospital setting differs significantly from bacteria found in a community setting primarily in their resistance to antibiotic therapy.                "Historically, staphylococci, pseudomonads, and Escherichia coli have been the nosocomial infection troika; nosocomial pneumonia, surgical wound infections, and vascular access-related bacteremia have caused the most illness and death in hospitalized patients; and intensive care units have been the epicenters of antibiotic resistance. Acquired antimicrobial resistance is the major problem, and vancomycin-resistant Staphylococcus aureus is the pathogen of greatest concern. The shift to outpatient care is leaving the most vulnerable patients in hospitals. Aging of our population and increasingly aggressive medical and surgical interventions, including implanted foreign bodies, organ transplantations, and xenotransplantation, create a cohort of particularly susceptible persons. Renovation of aging hospitals increases risk of airborne fungal and other infections.
Significant morbidity, mortality, and costs are associated with these infections. Many factors contribute to these dangerous infections. Most notably is the overuse of antibiotics and poor personal hygiene such as hand washing. Abundant evidence exists, however, that the hospital environment itself contributes to the problem by harboring virulent strains of bacteria, fungi, and viruses, and that many methods commonly used are ineffective and may actually spread contaminants.
Attempts to eradicate surface contaminates from the hospital setting have varied greatly in strategy and success. These have ranged from antiseptic soaps to fumigation with formaldehyde gas. Topical antiseptics are problematic for several reasons. First, they have recently been shown to actually induce antibiotic resistances and thus may be adding to the problem. Secondly, many surfaces such as keyboards, television sets, and monitoring controls are difficult if not impossible to decontaminate with liquid disinfectants without harming the electronics. Gas disinfection, while effective, is time consuming, hazardous to workers, and environmentally unwise.
Ultraviolet (UV) light has been long used for disinfection and sterilization. Ultraviolet light may be produced artificially by electric-arc lamps. Recently, the widespread availability of low to medium pressure mercury bulbs has led to the development of devices which use UV-C to decontaminate water supplies. UV-C is a high frequency wavelength of light within the ultraviolet band and has been shown to be the most bactericidal type of ultraviolet light. UV-C has wavelengths of about 2800 Å to 150 Å. To date, there are no published efforts to use UV-C to decontaminate or disinfect larger areas such as operating rooms. The only recent availability of the appropriate bulbs as well as significant safety concerns regarding worker exposure to UV-C likely contribute to the lack of efforts to use UV-C outside of self-contained water purification systems.

Area sterilizer and method of disinfection