An adaptive, discrete-time sliding mode controller (SMC) is disclosed which detects and adapts to gain variations in the controlled plant. The overall control effort is generated by combining a linear control effort with a discrete-time sliding mode control effort generated by switching between gains in order to drive the system's phase states toward a sliding line trajectory. A sliding mode variable .sigma..sub.k defines the position of the system phase states relative to the sliding line. The SMC controller is designed such that the sliding mode variable .sigma..sub.k crosses the sliding line and changes sign at every sample interval. For the nominal plant gain, the SMC controller is also designed such that the magnitude of the sliding mode variable .sigma..sub.k+1 =-.sigma..sub.k will remain constant (.sigma..sub.k+1 =-.sigma..sub.k) and substantially constrained to EQU .vertline..sigma..sub.k.vertline.=.DELTA./(1+.lambda.). where .DELTA. and .lambda. are predetermined design constants. The deviation in if the magnitude of .sigma..sub.k from nominal is a direct measure of the deviation in the plant gain. Accordingly, the present invention measures the error between the measured magnitude of .sigma..sub.k and the nominal magnitude, and uses this measured error to adapt to variations in the plant gain.

Sliding mode control (SMC) is a relatively new development in control systems which was first developed in Russia in the 1950's. It is a subclass of Variable Structure Control (VSC), control systems that switch between structures in a non-linear manner in order to drive phase states of the system toward a phase plane trajectory. The phase states of the system include the position error and its derivatives (velocity, acceleration, etc.); the location of the phase states within a phase plane define the state of the system at any given time, and the movement of the phase states through the phase plane is referred to as the phase state trajectory.
When the SMC is operating in a first structure, the phase states follow a first phase state trajectory, and when the SMC is operating in a second structure, the phase states follow a second phase state trajectory. By switching between the first and second structures, the phase states are driven toward a third phase state trajectory, referred to as the sliding line (or hperplane for higher order systems), defined within the phase plane where the first and second phase state trajectories intersect in opposite directions. The switching action is controlled by the location of the phase states relative to the sliding line; when the phase states cross the sliding line while following the first phase state trajectory, the system switches to the second structure to drive the phase states toward the sliding line by following the second phase state trajectory. In this manner, the phase states continuously switch across the sliding line as they follow the sliding line toward the origin of the phase plane (i.e., sliding mode). SMC has the advantage in that the closed loop response is defined by parameters in the controller and it is substantially insensitive to parameter variations in the plant and external load disturbances.
Initially, SMC systems were developed and implemented in continuous-time wherein the phase states are continuously monitored such that the system switches structures instantaneously when the phase states cross the sliding line. An inherent problem with this approach is that the continuous switching action may induce undesirable noise in the system (electrical and acoustic) and it may excite modelled (as well as unmodelled) system dynamics. The above referenced co-pending patent application entitled "Improved Chatter Reduction in Sliding Mode Control of a Disk Drive Actuator" discloses a method for reducing the amount of switching noise by defining a boundary layer around the sliding line and switching between structures only when the phase states exceed the boundary layer. Although this technique reduces the switching noise, there are other inherent problems with continuous-time SMC. Namely, to achieve the desired robustness to parameter variations and external disturbances, it can require gains in the individual structures that exceed the control effort limitations (e.g., exceed the available drive current).
Discrete-time SMC is a more recent development which addresses the drawbacks of continuous-time SMC by combining a conventional linear control effort with a discrete-time sliding mode control effort. This approach is discussed by Weibing Gao in "Discrete-Time Variable Structure Control Systems," IEEE Transactions on Industrial Electronics, Vol. 42, No. 2, April 1995. With discrete-time SMC, the phase states are monitored in discrete-time and the system switches between structures at the sampling rate rather than continuously. Thus, there is an inherent boundary layer about the sliding line with a width defined by the sampling period, as well as other parameters of the controller. Rather than switch continuously such that the phase states "slide" along the sliding line, the phase states switch across the sliding line in a zigzag manner while sliding toward the origin of the phase plane. Another characteristic of discrete-time SMC is that nominally the phase states will cross the sliding line at every sampling period, and the absolute magnitude of the distance between the phase states and the sliding line will remain within the inherent boundary layer.
The linear control effort in discrete-time SMC decreases the necessary switching control effort while still maintaining a certain degree of insensitivity to parameter variations and external load disturbances. However, the system's insensitivity to parameter variations depends on the width of the boundary layer; the system's robustness can be increased by increasing the boundary layer, but this requires an increase in the switching control effort and eventually leads to the same problems associated with continuous-time SMC. Increasing the boundary layer also limits the maximum slope of the sliding line since the sliding line must be constrained within a particular region of the phase plane in order to maintain global stability.
There is, therefore, the need for an improved discrete-time sliding mode controller that exhibits the desired insensitivity to parameter variations and external load disturbances, without increasing the switching noise and without requiring a large control effort in the switching term. A further object of the present invention is to provide a discrete-time sliding mode controller wherein the slope of the sliding line can be increased to a more optimal value within the phase plane while maintaining global stability.

Adaptive discrete-time sliding mode controller


A demodulation reference signal (DMRS) indication method includes: a base station allocating designated DMRS ports, numbers of layers and orthogonal cover code (OCC) lengths to a user equipment (UE) according to a DMRS configuration parameter indication table, wherein a plurality of DMRS configuration parameter indication entries with a plurality of OCC length combinations of at least two OCC lengths are recorded in the DMRS configuration parameter indication table; according to DMRS configuration parameter information allocated to the UE, generating corresponding DMRS indication information, and sending the DMRS indication information to a corresponding UE. Also disclosed are a base station, a UE and a DMRS indication system.

A communication system in related art, such as a Long-Term Evolution (LTE) system, a Worldwide Interoperability for Microwave Access (WiMax) system, a Wireless Local Area Networks (WLAN) system using a standard 802.11n, generally uses conventional two-dimensional (2D) Multiple-Input Multiple-Output (MIMO) technology. A fundamental principle thereof is to improve quality of transmission and a system capacity using degrees of freedom in 2D space of an antenna on a horizontal plane.
However, with no major breakthrough in existing physical-layer technology, a hotspot under research is to find a solution for further improving utilization of a spectrum of a wireless communication system. A feasible solution at the time is to extend the conventional 2D MIMO to three-dimensional (3D) MIMO by taking full advantage of a degree of freedom in vertical space, to improve system performance by taking full advantage of degrees of freedom in 3D space.
However, DMRS indication based on the 2D MIMO no longer applies when 3D MIMO is adopted. Therefore, there is a pressing need for a solution for DMRS indication based on 3D MIMO.

DMRS indication method and system, base station and user equipment

CHINA MOBILE COMMUNICATIONS GROUP CO., LTD.


A laser diode and a lens are fixed onto a laser fixing member. A laser beam emitted from the laser diode passes through the lens, and a part of the laser beam passes through a pinhole provided to a beam restricting plate. The pinhole is formed so that its diameter is smaller than the laser beam diameter at the beam restricting plate. The laser beam is transmitted therethrough while being diffracted.

1. Field of the Invention
The present invention relates to a semiconductor laser source for use in a laser beam printer, a laser facsimile apparatus, an image scanner for printing, a bar code reader, a copying apparatus, and a sensor.
2. Description of the Prior Art
A semiconductor laser source is used for various apparatuses such as the above-mentioned ones as an optical system using the coherence of a laser beam (e.g. as an optical pickup which is an application of a characteristic of the laser beam that it can be converged into a minute spot). In such an optical system, the light source has been reduced in size to reduce the power consumption. The size of the optical system has also been reduced. For example, as a lens system for coupling laser beams, the minute one with a diameter of several millimeters is known.
In the above-mentioned optical system, as shown in FIG. 1, a laser beam LB emitted from a semiconductor laser 1 is divided into a component A directly passing through a first surface S.sub.1 and a second surface S.sub.2 of a lens 2 and a component B first reflected by the second surface S.sub.2 and first surface S.sub.1 and then passing therethrough. Thus, the optical path lengths of the components A and B are different. Since the laser beam is highly coherent, deformation of a beam intensity pattern due to interference between the components A and B, that is, non-uniformity of a beam intensity (interference fringe) is caused in a beam spot formed. This nonuniformity of the beam intensity brings about various problems. For example, in a case where the optical system is employed for a sensor, noise increases when only a part of a laser beam is received by a sensing device, which may result in a malfunction.
In order to prevent the generation of nonuniformity of the beam intensity, generally, the lens is anti-reflection coated. The reflection prevention processing is performed by setting a plurality of lenses one by one at a planetary in a vacuum chamber and then applying to them a multi-layer coating including magnesium fluoride and titanium dioxide.
However, since a portion of the lens used to hold the lens is reduced because of the reduced size of the lens, setting of the lens in the above-mentioned multi-layer coating process is difficult, which complicates the work. In addition, the multicoating results in an increase of the cost.


A portable terminal with a touch screen and a method for displaying tags on the touch screen of the portable terminal are disclosed. The method includes: calculating a distance between the first and second touch points detected on the touch screen; identifying the number of tags that will be displayed, according to the calculated distance; and displaying at least one of the identified number of tags.

1. Field of the Invention
The present invention relates to portable terminals, and more particularly, to a portable terminal with a touch screen and a method for displaying tags on the touch screen of the portable terminal using a multi-touch detected on the touch screen.
2. Description of the Related Art
Portable terminals, such as cellular phones, personal digital assistances (PDA), MPEG-3 players, etc., have been developed with a plurality of functions and have included an input unit, such as a keyboard or a mouse etc., to allow a user to use those functions. The addition of keyboards and mice in the conventional portable terminals causes their size to be increased and causes a user to have difficulty carrying them. To resolve this problem, conventional portable terminals have been equipped with a touch screen instead of a keyboard or a mouse.
Touch screens are configured to combine an input unit with a display unit, where the input unit receives signals generated by a user tapping action and the display unit displays functions and data as the portable terminal is operated. Portable terminals with a touch screen provide a user interface that a user can intuitively recognize.
With the development of touch screen technology, touch screens can perform a multiple tapping recognition function that is called a multi-touch. Therefore, portable terminals with a touch screen can detect a multi-touch via the touch screen and perform a corresponding function. Multi-touch means that multiple tapping points are touched on the touch screen.
According to a multi-touch, the number of functions performed in the conventional portable terminals is limited. Examples of such functions are zooming in/out and rotating with respect to an image. It is necessary to develop functions that can be performed by a multi-touch detected on a touch screen.

Portable terminal with touch screen and method for displaying tags in the portable terminal

Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do


A guard and associated method for rain gutters includes a cap or deflector extending over a gutter of the type having a trough-shaped interior, a rear wall extending along a roof fascia, and a front lip with a channel and an end flange. A mounting bracket has a rear portion abutting the rear wall of the gutter, an upper portion supporting the deflector, and a front portion with a hook-shaped nose. The mounting bracket nose is configured for insertion under the end flange of the gutter, such that the mounting bracket is rotated rearwardly along a generally vertical arc about the nose toward the rear wall of the gutter, and shifted laterally into a skewed orientation within the gutter interior. The mounting bracket is then pivoted laterally along a generally horizontal plane about the nose into a perpendicular orientation within the gutter interior to retain the nose in the front lip of the gutter, and facilitate attachment of the rear portion of the mounting bracket to the rear wall of the gutter and the roof fascia.

The present invention relates to rain gutters for buildings and the like, and in particular to a guard and associated method to prevent leaves, twigs and other debris from entering the interior of the gutter.
Gutter protection systems, such as guards, caps, screens and shields, are well known in the art, and are designed to prevent leaves and other debris from entering the trough-shaped interior of the gutter, while directing runoff water to a desired location. Some types of gutter guards, such as those disclosed in U.S. Pat. Nos. 6,182,399 and 5,845,435, are incorporated into a complete gutter system of the type having a special gutter shape. Consequently, such guards cannot be used to retrofit an existing conventional gutter.
Some types of gutter guards, such as that disclosed in U.S. Patent Publication 2002/0073631 A1, attach to the existing hangers of a conventional gutter, while others, such as that disclosed in U.S. Patent Publication No. 2002/0069594 A1, employ special clips to attach the guard to the front lip of an existing gutter. In both such designs, extra strain is applied to the gutter and/or associated hangers as a result of the weight of the guard, as well as the runoff water and related debris. This additional weight can result in substantial problems, particularly when the existing gutter is installed without anticipating the additional weight of a retrofitted guard.
Many types of gutter guards are currently available, including those that use screens or expanded metal panels, as well as those using imperforate caps or top sheets. Typically, both of these designs rely upon the rain gutter itself for support, and/or must be fastened to the roof, resulting in increased installation difficulty and cost.

This patent is subject to a terminal disclaimer.


An apparatus for testing a porous medium is provided. The apparatus includes a liquid processing subsystem and a liquid weighing subsystem. The liquid processing subsystem is interfaced with the medium in a manner that establishes liquid contact there-between. The liquid processing and liquid weighing subsystems are sealably interconnected via an interconnecting liquid tube. The liquid weighing subsystem stores a liquid which flows therefrom, through the tube, through the liquid processing subsystem, and into the medium until it is saturated with the liquid. The liquid weighing subsystem automatically measures the weight of the liquid stored therein on an ongoing basis and uses these measurements to determine one or more hydraulic properties of the medium.

In the arts of soil science and hydrology the hydraulic properties of soils and other porous media are often measured in situ. These measurements are subsequently analyzed in various ways for various purposes such as studying the efficiency of irrigation and drainage, optimizing the availability of water for plants, optimizing the yield of crops, and minimizing erosion. These measurements can also be used to follow the movement of liquids in porous media, model soil pore structure, and predict plant growth and other associated factors.

Automated hydraulic property measurement apparatus


A control system is provided. The control system comprises an electronic processor configured to control operation of at least one wind turbine. The control system further comprises at least one weather radar unit positioned proximate to the at least one wind turbine and configured to generate weather data. The electronic processor is configured to control the operation of the at least one wind turbine based on the weather data generated by the at least one weather radar unit.

The present disclosure relates generally to the field of system prediction and control. More particularly, the present disclosure relates to prediction and control of systems such as wind turbines, wind farms and/or other systems related to weather.
Wind power has emerged as a primary source of renewable energy. However, the wind power industry faces challenges in the area of turbine reliability. Some of these challenges are related to the high structural loads in the drive train of the wind turbines and the difficulty in predicting the electrical power output. The structural loads and related failure states may contribute to equipment manufacturers offering short warranties (e.g., two year warranties) after which wind developers and power companies may expend significant resources to keep the turbines operational. Further, the difficulty in predicting wind turbine power (i.e., electrical power) output due to the variability of wind as an energy source may cause power companies to maintain reserve sources of electrical power (e.g., spinning but not providing power to the electrical grid).
Wind turbines have certain wind speed limits at which they can successfully operate. Wind turbines have upper wind speed limits and turbulence levels above which they may sustain significant or catastrophic damage. Wind turbines also have lower wind speed limits below which the turbines cannot operate. Many geographical areas rich in wind resources are also areas where violent frontal weather, with attendant thunderstorms, microburst, wind shear, and icing conditions, occur.

Wind prediction for wind farms through the use of weather radar


An archery bow assembly is provided including an open sided spacer which is mountable to an axle on an archery bow and removable therefrom without removing the axle entirely or partially from a limb of the archery bow. The spacer can mount on the axle adjacent a cam rotatable on the axle, and can include an outer perimeter and an axle aperture. A recess can extend inward from the outer perimeter to the axle aperture so that the axle aperture and recess form a continuous opening. The spacer can be of a C-shape or E-shape so that it can be frictionally pressed onto the axle and removed therefrom without removing the axle from the limb arms adjacent the cam. Related methods also are provided.

The present invention relates to archery products, and more particularly to a spacer to precisely position a cam on an axle of an archery bow.
Conventional compound and crossbow archery bows include a bowstring and a set of power cables that transfer energy from the limbs and cams, eccentrics or pulleys (which are all referred to generally as "cams" herein) of the bow to the bowstring, and thus to an arrow shot from the bow. The function of the cams is to provide a mechanical advantage so that energy imparted to the arrow is a multiple of that required of an archer to draw the bow. The cams typically are rotatably mounted to limbs via respective axles.
In most bows, a cam is rotatably mounted in a recess between free ends of a solid limb, or between two opposing limb arms of a split limb. An axle projects through the cam, and any associated bearings of the cam, as well as the free ends of the solid limb, or the opposing arms of a split limb. Sometimes, cylindrical bushings or circular washers are placed between the cam and the free ends or opposing arms of the limb to properly space or center the cam between those elements. To install these cylindrical bushings or circular washers, the axle must be removed from the limb, out from the limb recess, and then carefully redirected back into the limb recess, projecting through the center bore or hole of the cylindrical bushings or circular washers such that those elements are trapped on the axle.
While conventional cylindrical bushings or circular washers can position the cam between the free ends or opposing arms of a limb, they are tedious to install, and require full or partial removal of the axle from the limb and limb recess. Frequently, this requires that the bow be placed in a bow press to reduce the energy stored in the limbs so that the bow is safe to work on. This takes time and, of course, special equipment like a bow press. The components of the assembly, that is, the cam, the cylindrical bushings and/or the circular washers also have to be sequentially placed on the axle to ensure that the stack is appropriate along the axle, and achieves the desired placement of the cam along the axle. If the placement of a bushing or washer is improper, a user will remove the entire axle again to correct the misplacement. This can be tedious and time consuming. Likewise, if a bushing or washer of the wrong thickness is erroneously placed on the axle adjacent the cam, to replace that element with a correct or a better one, a user will remove the axle partially or fully from the limb.
Further, if a particular cylindrical bushing or circular washer is not of an appropriate thickness to provide a particular placement of the cam along the axle, an unwanted gap adjacent the cam or limb part can develop. As a result, the cam and components can slide laterally along the axle, which can lead to inconsistent and/or imprecise rotation of the cams. To replace the element, again, a user will use a bow press and remove the axle.
Accordingly, there remains room for improvement in the field of archery bows, and in particular, axle systems for rotating cams.


A compact driver device for driving an LED lighting device is provided. The driver device includes a substrate, power capacitor that provides LED driving current to drive the LED lighting device, and a power resistor. Advantageously, the power capacitor and the power resistor are attached to the substrate and are solderlessly connected to each other to provide a very compact driver device.

Light emitting diode (LED) driver is an important component of solid state lighting devices which became the lighting technology of choice for energy efficient environmentally friendly lighting. Currently, the most common solution is to apply pulse width modulation (PWM) to generate constant forward current and to control brightness by adjusting duty cycle. Depending on the input voltage, the output current and power, isolation, and other requirements a variety of PWM topologies have been used for LED driver, including buck, buck-boost, flyback, and SEP IC (Single Ended Primary Inductor Converter) topologies.
While PWM principle has been used in constant-current sources for decades, use of the PWM principle for LED lighting applications presents a number of challenges. One of the most challenging applications is in retrofit lamps that are defined as lamps compatible with existing sockets and fixtures designed for incandescent, halogen, fluorescent, compact florescent, and metal halide lamps and meet illumination requirements including Color Rendering Index (CRI). First, the LED driver must fit into a form factor defined by an evacuated glass vessel and developed over 100 years ago commonly known as A19 bulb or fit onto a standard body of a reflector lamp such as GU10 or a PAR. Next challenge is thermal management. In a LED lamp, all energy which is not converted into visible light will be turned into heat dissipated in the driver and emitter. Driver efficiency becomes an important factor as it affects heat generation and overall efficiency of the lamp. Further, the reliability of an LED driver must match 50,000 h—the life expectancy of an LED emitter. An LED lamp is expected to operate at case temperatures exceeding 100° C. and to cycle between ambient and operating temperatures several times a day which is equivalent to more than 10,000 thermal cycles over 10 year life. Thus, Current Joint Electron Devices Engineering Council (JEDEC) standards of thermal cycling reliability in the range of 500-1000 cycles are clearly not sufficient for retrofit LED lights. In addition, as a switched mode power supply, an LED driver requires optimization to meet power factor and EMI (Electromagnetic Interference) requirements. Once form factor, thermal management, efficiency, and reliability problems are solved, the cost becomes yet another problem, as high-grade 125° C., or higher rated components, must be used and design complexity increases to meet all the requirements discussed above.
The current method of LED driver manufacturing uses conventional printed circuit boards (PCB) with standard packaged components. However, such conventional PCBs' cannot meet the efficiency, thermal management, reliability and cost requirements discussed above. Therefore, there is a need to provide an improved LED driver solution which solves the above-discussed problems.

Integrated electronic device for controlling light emitting diodes


Devices consisting of a signal source and a signal sink connected by a transmission channel for transmitting high-frequency signals, as well as digital signals between moving parts. By eliminating wave reflections, the signals are transmitted such that reliable wide-band transmissions are ensured.

The invention relates to devices for transmitting high-frequency as well as digital signals between moving parts, consisting of a signal source and a signal sink connected by a transmission channel. Specifically, the present invention relates to the transmission of high-frequency signals such as intermediate-frequency signals or even digital data, rather than high-performance transmission in the microwave range. Such signals are normally made available as non-symmetrical signals.
High-frequency and also digital signals must frequently be transmitted between parts which are mobile relative to each other. A typical application of such transmission paths is radar technology, where signals are transmitted from the transmitter/receiver unit to the antenna.
Various devices are known for transmitting non-symmetrical signals. For instance, the transmission may be performed in a capacitive manner via a package of plates resembling a variable capacitor. The main problem of this arrangement is the current path between the mutually mobile parts is not precisely defined.
Initially, the current flows through the plate package. The return path is normally the frame or chassis, which is mostly implemented as a screen or housing. When the parts are rotating relative to each other, however, it is particularly difficult to achieve an effective low-inductance frame or ground connection. This results in the inherent problems with the previous transmission systems. In this case, it is very difficult to achieve constant transmission characteristics and a constant cross-talk.
Even though transmission paths implemented with the aid of variable capacitors have a comparatively large bandwidth, in distinction from other transmission techniques, they present the disadvantage of high engineering expenditures (in terms of the plate packages) and an upper limit frequency which is far below a wavelength corresponding to the dimensions of the plate package. Another disadvantage of this arrangement is their high sensitivity to mechanical loads as well as shocks and vibrations.
Transmission paths based on coupled resonance circuits present good transmission characteristics, but naturally they only have a very narrow band. They have high expenditure requirements (in terms of manufacturing technology), and may possibly require trimming. For different applications, each of these elements must be dimensioned differently. As a result, it is nearly impossible to obtain a wide range of products with such transmission paths in a standard design.
In order to avoid the disadvantages of these arrangements, several approaches have been tried to improve the high-frequency transmission characteristics of conventional collector rings. One such approach involves a method of simultaneously inputting the signals at several locations so that the occurrence of resonances at elevated frequencies is ensured during limited operating conditions. In another approach, attempts have been made to configure a slip ring with a defined wave resistance and to terminate it with the wave resistor at a suitable location.
Both approaches are entirely unsuitable for broad-band high-frequency transmission because they begin from a closed annular contact path. This path will always be a capacitive load. Even when a resistor is mounted, which corresponds to the wave resistor, a closed ring can never be designed to be free of reflections. With reference to FIG. 4 and FIG. 5, the explanation for this is as follows.
FIG. 4 shows a closed ring which is designed with a wave resistor of Zo=50 xcexa9. An impedance 15 with R=50 xcexa9 is mounted on this wave resistor. FIG. 5 shows a small segment of the ring including the impedance. On the assumption that the ring is actually terminated, and free of reflections, a wave propagating along the direction would encounter an impedance ahead of the impedance 15. This is the result of mounting in parallel the real resistor (with R=50 xcexa9) and the line (with Zo=50 xcexa9) for the purpose of continuing conduction behind the resistor. The value of the parallel circuit is 25 xcexa9. As a result, the line cannot be free of reflections for the wave ahead of the resistor. Even with all other combinations of wave resistors and terminating resistors, a line free of reflections is unobtainable.
The previously described non-contact transmission methods are superior to the contacting methods, because they contain a negligible amount of mechanical friction and hence a lack of abrasion or contact wear. The service life of such non-contact transmission systems is essentially longer than that of the contacting methods. This is particularly true in the case of high speeds in the relative motion of the moving parts. Nevertheless, these transmission methods have the inherent disadvantage of a frequency limit that is lower. As a function of the particular design, this limit may vary. What is characteristic, however, is the fact that a common-mode component with a frequency of 0 (zero) cannot be directly transmitted.
The digital signals occurring in practical industrial application, e.g. the signals used in advanced bus systems, vary between almost static signals with extremely low frequencies and signals with a maximum clock rate predetermined by the bus system. The lowest frequencies occurring are mostly below the lower limit frequency of the previously described non-contact transmission systems.
Hence a direct transmission of these signals is, as a rule, not possible. The known modulation or coding methods are a remedy in this respect. Both methods require high engineering expenditures. The coding methods which are well suited for digital signal transmission, such as the Manchester coding approach, require a wider bandwidth of the transmission channel merely on account of their coding. As a result engineering expenditures and costs of the transmission path are increased. Moreover, regeneration of the digital signal""s timing is required in the majority of coding applications. This timing is frequently unreconstructable from the signal. Only with a suitable data structure, is timing regeneration possible via PLL elements. Such circuits are mostly suitable for a previously determined data rate. In the event that the non-contact transmission path should be transparent in terms of data and protocol, only the expensive modulation methods can be employed.
The object of the present invention is to improve a device for transmitting signals between mobile elements consisting of a signal source and a signal sink connected by a transmission channel such that a reliable wide-band transmission is ensured. This is accomplished without a frame or ground connection being required between the moving parts.
A further object of the present invention is to provide devices that are suitable for transmitting high-frequency signals and/or digital signals. Moreover, according to the object of the invention, a transmission that is transparent in terms of protocol and data, with a data rate lower than the lower limit frequency of the transmission path for the transmission of digital signals should be possible with low engineering expenditures and without an increased bandwidth requirement.
These and other objects and advantages are achieved by the present invention device, in which a signal source and a signal sink are connected by a transmission channel such that the transmission path has a symmetrical structure and hence a precisely defined current path is available. The current paths for emission and return are obtained in approximately identical ways. Therefore, the signal flow must not be returned via another path which is poorly defined. Hence, poor frame or ground connections are irrelevant and a frame or ground connection may even be eliminated entirely. As a result, a separation of potentials of the parts that are movable relative to each other can be achieved at the same time. Moreover, due to the symmetrical transmission, an excellent in-phase rejection is achieved. This is particularly expedient, and is specifically true in those cases which involve poor ground connections between the moving parts such that substantial differences in voltage may be present between these elements.
In one embodiment of the invention, optional matching circuits are provided for a conversion of non-symmetrical into symmetrical signals and vice versa. Such matching circuits are necessary when the signal source, or even the signal sink operate, on non-symmetrical signals.
In another embodiment of the invention, the coupler means consist of two oppositely facing pairs of conductive surfaces. The conductor surfaces should be designed such that they are matched with the path of travel and the widest possible overlapping of the conductive surfaces will always be present on the moving parts. The individual conductor surfaces of each pair should be symmetrical as far as this is possible, in order to ensure the symmetry of the arrangement as a whole.
In a further embodiment of the invention, the matching circuits are implemented via passive components. For instance, several circuits are known for impedance matching and symmetry via lines and also via transformers are known. Here too, designs using other passive components are possible.
Another embodiment of the arrangement utilizes active components in the matching circuits. The functions of these matching circuits can be implemented by the use of semiconductors and integrated amplifiers without any additional problems. Moreover, the first matching circuit can be implemented via an amplifier having an inverting and a non-inverting output. Two separate amplifiers are, of course, equally suited for application. The second matching circuit can hence be implemented likewise via a differential amplifier.
In a yet a further embodiment of the present invention, transmission of digital information, a logic gate with an inverting and a non-inverting output are used in the first matching circuit. As before, two separate logic gates may equally be employed. The second matching circuit may be implemented by means of a logic circuit having a differential input.
In still another embodiment according to the invention, the broad-band signal transmission characteristics of a line terminated so that it is free from reflections is utilized. Such a line may be structured, in correspondence with the prior art, as a coaxial line, a strip line or as a symmetrical two-wire circuit. Actually, other types of lines are also suitable for guiding electromagnetic waves. The electromagnetic waves have a constant defined wave resistance over their entire length and are terminated on at least one end with a resistor that corresponds to the wave resistance such that they are free of from reflections. The essential aspect, however, is the transmission of TEM waves on electrical lines.
As a rule, such lines are terminated on both ends by the wave resistor. However, a signal source with a non-matched internal resistance may equally be connected to a line which, on its part, is terminated with a resistor that corresponds to the wave resistance such that it is free of reflections. Reflections cannot occur on the termination which is free of reflections. With a circular arrangement of such a line, in correspondence with the path of the rotating movement, the information may be obtained along the line.
In the embodiments reference is made to the term xe2x80x9clinexe2x80x9d. In fact, this term relates to all lines and also several lines. The term xe2x80x9crotatingxe2x80x9d movement refers to a rotating motion over any angular range whatsoever, and hence even applies to limited angular ranges up to continuous rotating movements.
In a further embodiment of the present invention, the signals are xe2x80x9ccoupled outxe2x80x9d of this line via a high-impedance output circuit. This high-impedance circuit therefore does not give rise to reflections at the output-coupling site. Such an output circuit may utilize a transformer, or even an amplifier with a high-impedance input or an impedance transformer.
In another embodiment of the invention, the signal is xe2x80x9ccoupled outxe2x80x9d via a field probe. This probe may be both an E-field probe or an H-field probe. Moreover, the probe can even be a combination of both types and can be a second coupled line. What is essential in the design of the field probe is the fact that it will not influence the field of the line in a way which will create reflections on the line. An attenuation of the signal on the line by the probe is permissible, because any further reflections do not occur in this case.
In another embodiment of the present invention, signals may even be coupled into contact with the line. To this end, it is necessary to terminate the line on both ends in a form that is free of reflections, because waves propagate from the rotatable input site along both directions of the line.
In a further design signals are coupled into the line via a coupler element which achieves the coupling of the E-fields and/or the H-fields. In the simplest form this coupling element may be another line arranged in parallel with the first line.
In accordance with the object of the invention, the device is configured specifically for the transmission of digital signals, such that the transmitter is provided with a signal processing circuit which increases the slope of the signal flanks of the digital signal supplied by the data source. This permits the reciprocal values of the rise time and the drop time to be higher than the lower limit frequency of the transmission path. Furthermore, a logic evaluation circuit is provided in the receiver which reconstructs the original signals from the pulses supplied by the transmission path by differentiation of the signals emitted by the transmitter.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

Device for signal transmission between moving parts


A transconductor includes first and second differential pair compound transistors coupled between a first reference node and a common node. The compound transistors are commoned to each other at a common node. A single current source is coupled between the common node and a second reference node. In an alternate embodiment, a current turnaround circuit may be used to convert the transconductor to a single ended configuration.

Complex analog integrated circuits typically include circuitry to provide access to some internal analog signals for test purposes. To access internal analog signals, the internal analog signals routed as inputs to a multiplexer that is used to select one of the signals as the input to an analog output buffer. The buffer functions to buffer the external load, such as the test equipment, from the integrated circuit that is not designed to drive an external load.
The prior art has many forms of buffer circuits. One widely used prior art buffer circuit includes a differential source coupled pair of transistors with an output source follower. This circuit provides high gain and large bandwidth but has the shortcoming of limited input voltage swing, particularly in the positive direction. The source follower transistor prevents the input voltage from reaching the positive voltage rail due to the threshold and ON voltage of the source follower transistor. A further shortcoming of this circuit is the necessity to continuously sink a large current required for discharging an external capacitive load. For a rapid discharge, a large current is required. The sink current must also be provided by the source follower transistor when charging the external load. Thus, the source follower consumes large amounts of power.
A circuit that appears to overcome shortcomings of the above-mentioned circuit is disclosed in IEEE Journal of Solid State Circuits, Vol. 26, No. 6, June 1991, pages 859-867, the disclosure of which is hereby incorporated by reference. The circuit is depicted in FIG. 3C of the article and is an operational transconductance amplifier, or basic g.sub.m cell. The article teaches using a composite differential pair transistor with current mirrors to provide the output currents. The circuit has linear characteristics voltage-to-current over a large differential input voltage range. The input voltage signal levels are maintained as large as possible to obviate signal-to-noise ratio problems. The linear output versus input characteristics are obtained without feedback in the circuit. The p-channel devices serve as voltage followers buffering the input voltage across the resistor while the four constant current sources force any change in the resistor current to be directly reflected to the drain currents of transistors M2 and M2' which is mirrored to the output by transistors M3 and M3'.
Linear voltage transfer characteristics are typically obtained by employing linear feedback elements around a very high gain voltage amplifier. For use as a voltage buffer, this circuit has the shortcoming of low voltage-to-current gain which results in limited bandwidth. Wide bandwidth is important because the buffer must have a bandwidth at least as great as the bandwidth of the intermediate signals to prevent attenuation of frequencies in the internal analog signals being presented at the buffer output. Ideally, the gain of the buffer should be unity across the entire frequency range of interest so no attenuation of the intermediate signal occurs. This would assure that the intermediate signal is not distorted by the buffer.
It would be desirable to have a highly linear voltage buffer that would provide a wide bandwidth and consume little power. Such a buffer would have a large transconductance such that it would only require a small differential voltage input to result in a relatively large change in output current, thereby providing low distortion.

Transconductor employing differential pair composite field effect transistors


A touch sensor device including a first conductive pattern disposed on a substrate and a first polymer layer disposed on the first conductive pattern. The first polymer layer includes a first conductive region and a first non-conductive region. The touch sensor device also includes a second polymer layer disposed on the first polymer layer. The second polymer layer includes a second conductive region and a second non-conductive region.

Field
Exemplary embodiments relate to a touch sensor device and a manufacturing method thereof.
Discussion of the Background
Electronic devices, such as a liquid crystal display (LCD), an organic light emitting diode (OLED) display, and an electrophoretic display may include a touch sensing function that interacts with a user. The touch sensing function senses a change in pressure, charge, or light that are applied to a screen of a display device when an object (i.e. a user's finger or a stylus pen) to a touch surface, thereby determining contact information of the object (i.e., whether the object approached or contacted the touch surface, or the contact position of the object).
The touch sensing functions of several electronic devices may be implemented by a touch sensor. The touch sensor may be classified as a resistive type, a capacitive type, an electro-magnetic type (EM), and an optical type.
The resistive type based touch sensor includes two electrodes spaced apart from each other and may contact each other by a pressure from an external object. When the two electrodes contact each other, the touch sensor may determine the contact positions, by detecting a change in voltage in response to a change in resistance at the contact position.
A capacitive type touch sensor includes a sensing capacitor formed from multiple sensing electrodes capable of transferring a sensing signal. The capacitive touch sensor senses a change in capacitance or a charged state of charge of the sensing capacitor generated when conductors (i.e., an object such as a finger) approach the touch screen or touches the touch screen. If a conductor touches, then the capacitive touch sensor may determine the touched position. The capacitive type touch sensor may include touch electrodes that are disposed in a touch sensing area capable of sensing a touch as well as signal transfer wires that are connected to the touch electrodes. The signal transfer wires may transfer a sensing input signal to the touch electrode or transfer a sensing output signal of the touch electrode that is generated in response to a touch to a sensing signal controller.
The signal transfer wire may generally be positioned in a peripheral area positioned outside a touch sensing area of a touch sensing panel or may be positioned in the touch sensing area.
Various display devices use a heavy and fragile glass substrate. Therefore, these display devices have a limitation in portability and have a large screen display. Using lighter weight materials for the substrate may enhance the portability and flexibility of display devices. However, display devices with touch capabilities have complex manufacturing processing, are still rigid and relatively large due to the touch sensor device within the display devices.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Touch sensor device and manufacturing method thereof


A communications system includes a GPS receiver that receives GPS position data and GPS correction data, a mobile device having a first transceiver and an adapter coupled to the GPS receiver and having a second transceiver and a voltage regulator. The mobile device accesses RTK correction data over a cellular network using a current GPS position and processes the RTK correction data. The second transceiver of the adapter receives the RTK correction data over a wireless signal sent by the first transceiver of the mobile device. The adapter converts the RTK correction data so that the RTK correction data is receivable by a serial port on the GPS receiver that the adapter is coupled and the voltage regulator derives power from the GPS receiver to power the adapter.

Satellite navigation systems (i.e., global positioning systems (GPS)) provide location and time information anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. GPS is freely accessible to anyone with a GPS receiver. Such GPS receivers are found in various commercial equipment including surveying equipment, tractors, bull dozers, land levelers and the like, and are used for the accurate manipulation and analysis of large amounts of geospatial data. For example, GPS-based applications are useful in precision agriculture and are being used for farm planning, field mapping, soil sampling, tractor guidance, crop scouting and soil/plant treatment.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.

Device for inputting RTK correction data to a GPS


A higher layer at a base station generates and passes messages to Layer 2, which generates and appends a CRC value to each message. The messages are encapsulated in frames at the physical layer, which generates and appends a CRC value to each frame. The base station transmits the frames on a control channel. The physical layer at a wireless device processes the control channel and decodes each received frame to obtain a decoded frame. The physical layer forwards the decoded frame to Layer 2, regardless of whether the frame passes or fails a CRC test. Layer 2 processes the decoded frame, even if the decoded frame fails the CRC test, to extract messages sent in the decoded frame. Layer 2 checks each extracted message based on its CRC value and forwards each message that passes the CRC test to the higher layer.

I. Field
The present invention relates generally to communication, and more specifically to a method and apparatus for receiving a control channel in a wireless communication system.
II. Background
A base station in a wireless communication system (e.g., a cellular system) may transmit various types of messages to wireless devices. These messages may include user-specific messages sent to specific wireless devices, multi-cast messages sent to a group of wireless devices, and/or broadcast messages sent to all wireless devices. The system typically employs a protocol stack to process messages for transmission and reception. The protocol stack includes a number of layers such as Layers 1, 2, and 3, which are often referred to as a physical layer, a link layer, and a higher layer, respectively. Data is passed downward between the layers in the protocol stack at a transmitter and passed upward in the protocol stack at a receiver.
At the base station, an application at Layer 3 generates messages for the wireless devices and passes these messages to Layer 2. Layer 2 processes the messages from Layer 3 to achieve the functionality designed for Layer 2 and provides frames to the physical layer. There may be no defined relationships between the messages and frames, and each frame may carry a partial message, a complete message, or multiple partial and/or complete messages. The physical layer processes (e.g., encodes and modulates) each frame in accordance with a control channel used to send the frame. The physical layer typically employs an error detection code, such as a cyclic redundancy check (CRC) code. The physical layer would then generate a CRC value for each frame and append the CRC value to the frame. The CRC allows the wireless devices to perform error detection to improve data reliability. The base station transmits the frames via a wireless channel.
A wireless device performs the complementary processing to recover the messages sent by the base station. The physical layer at the wireless device processes (e.g., demodulates and decodes) data received via the wireless channel and further performs error detection for each decoded frame. The physical layer typically forwards frames that are decoded correctly (which are called good frames) and discards frames that are decoded in error (which are called erased frames). Layer 2 processes the good frames obtained from the physical layer, recovers the messages sent by the base station, and forwards the recovered messages up to the higher layer.
The wireless device inevitably receives some frames in error because of noise and other impairments in the wireless channel. The percentage of erased frames may be relatively high for an impaired wireless channel with poor channel conditions. The wireless device typically loses all messages sent in the erased frames. The higher layer would then utilize the available recovery mechanisms to deal with the lost messages in the erased frames. The performance of the wireless device typically degrades due to the lost messages.
There is therefore a need in the art for techniques to improve the likelihood of recovering messages sent in a wireless communication system.

Method and apparatus for receiving a control channel in a wireless communication system


An apparatus and method for manufacturing a highly efficient flexible thin metal film-laminated strip by improves adhesiveness between a polyimide strip and a thin metal film, and removes stress from thin films laminated through magnetron sputtering, which is a dry deposition process. The stress-free flexible circuit board manufacturing method includes the steps of: a) depositing a seed layer on the substrate using the magnetron deposition source; b) depositing a compressive thin film using the single magnetron deposition source arranged next to the magnetron deposition source; c) depositing tensile thin film using the dual magnetron deposition source arranged next to the single magnetron deposition source; and d) repeating the steps b) and c) so as to sequentially and alternately deposit compressive thin films and tensile thin films thereby obtaining a thick film with a desired thickness.

Such a thin metal film-laminated strip may be fabricated by heating and pressing a rolled or electrolytic metal film (e.g., copper film), or the like on an adhesive-coated surface of a plastic strip (e.g., polyimide strip), thereby adhering the metal film to the plastic strip. Alternatively, such a thin metal film-laminated strip may be fabricated by applying a resin solution to a surface of a thin metal film (e.g. copper film), wherein the resin solution is prepared by solving a thermosetting resin with a proper organic solvent and then curing the thermosetting resin by heat simultaneously with vaporizing the solvent. With these methods, it is impossible to cope with high density wiring required in the semiconductor industrial due to difficulty in finely processing such a metal film in a width of not more than 10 μm because the thermal performance of the adhesive is inferior to that of the substrate (e.g., polymer strip), and the resultant metal film formed by the methods has a thickness of not less than 10 μm, which is too thick to be finely processed. In addition, the above-mentioned methods reveal vulnerability in terms of dimensional stability and flexibility of a final product. Recently, in order to overcome these problems, a metal for forming a conductor circuit (hereinafter, to be referred to as "circuit forming metal") is directly deposited on a plastic strip through sputtering, or a metal layer different from the circuit forming metal is deposited on the plastic strip through sputtering prior to depositing the circuit forming metal, so that the metal layer is interposed between the circuit forming metal and the plastic strip.
When forming a thin film by sputtering, a target formed from a thin film forming material is located within a vacuum chamber, a substrate is located at a position corresponding to the target, and then argon is introduced into the vacuum chamber. The target is negatively charged, and plasma is formed within the vacuum chamber, thereby ionizing argon. In addition, argon ions hit the surface of the negatively charged target. As such, particles are scattered from the target by the energy applied by the argon ions hitting against the target, and are then deposited on the substrate.
Sputtering processes employed for forming a thin metal film include diode sputtering, bias sputtering, RF sputtering, triode sputtering, and magnetron sputtering. The magnetron sputtering, which is most frequently used among the above-mentioned sputtering methods, has an advantage in that because a magnet is mounted on the rear side of a target, plasma is formed more densely at the area corresponding to the magnet as compared to the other area, thereby rendering more atoms scattered from the target, which increases the deposition rate.
Even if a thin metal (e.g., copper) film is deposited through magnetron sputtering, the metal film is stressed if it has a thickness of several or more microns. Therefore, when forming a thick metal film with a thickness of several or more microns, a thickness of not more than 1 μM of the film is firstly deposited through a dry deposition process employing magnetron sputtering, and then the remainder of the film is formed through wet electroplating.
Like this, when forming a laminated film with a thickness of several or more microns, wet electroplating is also carried out in combination with a dry deposition process because it is difficult to control stress only with a dry deposition process. If wet electroplating is also employed, a process for manufacturing a flexible metal (e.g., copper) film-laminated strip is complicated, and a manufacturing space should be increased. As a result, manufacturing costs and time are substantially increased. Furthermore, the electroplating has a problem of causing environmental pollution.
However, if thin metal (e.g., copper) films to be laminated are formed completely through a dry deposition process, a metal film-laminated strip is liable to be deformed due to the stress induced in the laminated film as the thickness of the metal film is increased. Thus, it cannot be assured to obtain a thickness of several or more microns for the copper film-laminated strip.

Apparatus and method for manufacturing stress-free flexible printed circuit board

Sungkyunkwan University Foundation for Corporate Collaboration


There is provided an apparatus and method for disrupting radar systems. The apparatus comprises a chamber (110) for attachment to a vehicle, a radar countermeasure material (130) in the chamber, the radar countermeasure material comprising a plurality of hollow fibres, wherein the inner surface of at least some of the hollow fibres is at least partly coated with a conductive substance, and a release means (140) for dispensing the radar countermeasure material out of the chamber.

Radar systems operate by transmitting radio waves, also known as radio signals, in a predetermined direction from a transmitter. Whilst certain objects in the path of the radar will absorb the signal, other objects, particularly conductive materials, will cause the signal to be reflected back to a receiver. By measuring the time taken to receive the reflected signal, as well as the direction of transmission and reception, the distance and general direction of the object causing the reflection can be determined.
Radar has particular use in military applications. It is often desirable to avoid detection by radar. One method of avoiding detection is by using decoy countermeasures that give a false impression of the target's location, or prevent a radar system "seeing" a target. It is an aim of the present invention to mitigate one or more problems associated with the prior art.

Lightweight tuneable insulated chaff material


A method for providing voice communications at an optical amplifier site of a DWDM system is disclosed. The method generally comprises receiving an optical service channel at the amplifier site and converting an optical signal of the optical service channel to a digital electrical signal at the amplifier site. The optical service channel carries voice data and has a wavelength that is out of band with respect to wavelength bands of a multiplexed payload channel of the DWDM system. The method further includes sending the digital electrical signal to a router configured to support voice over IP.

The present invention relates generally to communication networks, and more specifically, to a dense wavelength division multiplexing (DWDM) system configured to support IP telephony at remote equipment site locations.
Historically service providers have used several layers of equipment to construct high-speed data networks (e.g., routers over ATM switches over Synchronous Optical Network/Synchronous Digital Hierarchy (SONET/SDH) network elements). Each piece of equipment performs a unique function. For example, ATM switches enable traffic engineering and SONET/SDH network elements provide performance monitoring and ring-based protection. A large amount of equipment is needed under this model, and the cost of delivering data services in this manner is very high. Constant upgrades are required for all of these network elements as the network grows, thus, the model does not scale well.
Furthermore, since optical signals become attenuated as they travel through fiber they must be periodically regenerated in core networks. In SONET/SDH optical networks each separate fiber carrying a single optical signal requires a separate electrical regenerator every 60 to 100 km. As additional fibers are added in a core network, the total cost of regenerators becomes very large. The regenerator receives a modulated optical signal, transforms it to an electronic signal, amplifies it, and then converts the electronic signal back to an optical signal of the same modulation and bit rate. Regenerators only amplify a single wavelength. Therefore, considering that in an optical link there are several regenerators, in a multiwavelength fiber system the maintenance cost is significant.
DWDM technologies allow IP service providers to achieve functionality without the expense of deploying SONET/SDH and ATM equipment or protocols. Wavelength Division Multiplexing (WDM) is an optical technology that couples many wavelengths in the same fiber, thus effectively increasing the aggregate bandwidth per fiber to the sum of the bit rates of each wavelength. Dense WDM (DWDM) is a technology with a larger (denser) number of wavelengths (e.g., >40) coupled into a fiber than WDM. Systems may support, for example, 100 wavelengths per fiber, enabling a single fiber to carry several hundred gigabits of information. DWDM increases the capacity of embedded fiber by first assigning incoming optical signals to specific frequencies within a designated frequency band and then multiplexing the resulting signals out onto one fiber. DWDM combines multiple optical signals so that they can be amplified as a group and transported over a single fiber to increase capacity. Each signal can be at a different rate and in a different format. DWDM applications include ultra-high bandwidth long haul as well as ultra-high-speed metropolitan or inner city-networks, and at the edge of other networks such as SONET, Internet protocol (IP) and asynchronous transfer mode (ATM).
Long-haul DWDM systems take standard optical signals from elements such as SONET/SDH network elements, IP routers, or ATM switches and convert each signal to a distinct, precise wavelength (e.g., in the 1530 to 1610 nm range). These individual wavelengths are then combined (optically multiplexed) onto a single fiber. In the receive direction of the system, the reverse process takes place. Individual wavelengths are filtered from the multiplexed fiber and converted back to a standard signal to the client. The complete DWDM system typically includes modules for each client interface in addition to equipment for multistage optical combining or splitting of wavelengths, amplification, and management/control.
DWDM systems reduce the need for and cost of electrical regeneration over long distances. As a result, virtually all operators of long distance fiber optic networks have implemented or expect to implement DWDM. The introduction of optical amplifiers in conjunction with DWDM systems has significantly reduced the cost of long-haul transmission. A single optical amplifier is able to reamplify all of the channels on a DWDM fiber without demultiplexing and processing them individually. The optical amplifier merely amplifies the signals, and does not reshape, retime, or retransmit them as a regenerator does. The signals may still need to be regenerated periodically, however, this can now be done approximately every 1000 kilometers. One optical amplifier can thus replace about 40 separate regenerators.
Since the channels are not demultiplexed at locations of optical amplifiers, a data channel is not typically available at remote geographic locations where the optical amplifier is located. If data access is required at these remote locations additional equipment is required to separate and pull off one or more channels. Furthermore, if voice communication is required, a public telephone line must be installed at each remote line site.
There is, therefore, a need for a system and method for providing data and voice access at optical amplifier location sites without the need for additional demultiplexing equipment or telephone lines.

DWDM system with IP telephony provisioning at remote locations


Certain aspects of the present disclosure provide an apparatus. The apparatus comprises a support structure comprising at least one microphone sensor, and a first material layer disposed adjacent to the support structure, wherein a first layer of air is formed between the first material layer and the support structure, the first layer of air being adjacent to the microphone sensor. In certain aspects, multiple material layers may be used, each of the material layers forming a layer of air. For instance, the apparatus may also include a second material layer disposed adjacent to the first material layer, wherein a second layer of air is formed between the first material layer and the second material layer.

Aspects of the present disclosure generally relate to a microphone device.
Headphones and speakers can include any number of microphones. The microphones may be used for, but would not be limited to, one or more simultaneous or asynchronous conditions of the following uses: active noise cancellation, noise reduction, and/or communication. Microphones may be used in various environments that may impact user experience. For example, in a harsh environment, microphones should be protected against water, sweat, dust, etc. As another example, in windy conditions, wind noise may degrade the quality of the audio signal sensed by the microphone. Therefore, there is a need for improvements in the signal-to-wind noise ratio of microphones.


A motorcycle helmet with a brake light includes a duty cycled receiver circuit for receiving a radio frequency (RF) signal from a transmitter located on the motorcycle. The receiver circuit is generally turned off if the RF signal is not present. When the receiver detects the RF signal, the receiver is turned on. The brake light is illuminated when the receiver receives the RF signal. The brake light includes LEDs for providing light. The lens is a plastic lens which provides superior performance having spherical indentations on an interior surface.

The present invention relates generally to headgear including a warning device. More specifically, the present invention relates to a headgear including a light for communicating the presence or action of the person wearing the headgear.
In a preferred embodiment, the invention relates to a motorcycle helmet including a brake light. The helmet is described herein with reference to a motorcycle operator and a brake light, however, the invention is not so limited. The invention is, in fact, applicable in any application where a safety device may be mounted on articles worn by an operator. Presently, motorcycle brake lights are mounted to the rear fender of the motorcycle. This placement of the brake light is too close to the ground to be readily seen by the operators of other motor vehicles.
In order to make motorcycle brake lights easier to see, U.S. Pat. No. 4,760,393, issued to Reilly on Jul. 26, 1990 discloses a brake light mounted to the motorcycle helmet. The apparatus disclosed in the Reilly reference operates as follows. When the brake pedal is depressed, a switch is closed. A transmitter produces an encoded signal in response to the closed switch. A receiver inside the motorcycle helmet receives the encoded signal. A binary decoder inside the receiver demodulates and decodes the signal. If the decoded signal matches a predetermined code, the decoder turns on the brake light mounted inside the helmet.
Heretofore, prior art motorcycle helmets with brake lights have been found to be disadvantageous because the battery which powers the circuits and brake light in the helmet is drained too quickly. Particularly, the receiver circuit and the brake light require a significant current to accurately produce a visible brake signal. Thus, there is a need for a motorcycle helmet with a brake light which requires reduced power to produce an effective brake signal.


A non-occluding intravascular pump comprises a shroud providing an inlet for incoming blood flow and an outlet for outgoing blood flow, wherein the shroud is a cylindrical housing; an impeller positioned within shroud, wherein a central axis of the shroud and impeller are shared; a motor coupled to the impeller, wherein the motor rotates the impeller to causes blood to be drawn through the inlet and output to the outlet, and the motor is centrally disposed and shares the central axis with the shroud and the impeller; and a plurality of pillars coupling the motor to the shroud, wherein the pillars secure the shroud in close proximity to the impeller. Various design features of the pump may be optimized to reduce hemolysis, such as, but not limited to, inlet length, impeller design, pillar angle, and outlet design.

Blood pumps may exert stresses on blood that cause hemolysis or blood clotting. A blood pump may provide an inlet, housing, impeller, outlet, and motor. There may be various hotspots in a pump's design of such components that may exert high stress on blood that can cause hemolysis or blood clotting. In addition to health risk associated with hemolysis and blood clotting, these factors may also impair operation of the blood pump. An example of a blood pump can be found in U.S. Pat. No. 8,012,079.
The improved non-occluding intravascular blood pump systems and methods discussed herein reduce and minimize shear forces that can cause hemolysis or blood clotting.

Non-occluding intravascular blood pump providing reduced hemolysis


Embodiments of the present invention provide improved microfluidic devices and related apparatus, systems, and methods. Methods are provided for reducing mixing times during use of microfluidic devices. Microfluidic devices and related methods of manufacturing are provided with increased manufacturing yield rates. Improved apparatus and related systems are provided for supplying controlled pressure to microfluidic devices. Methods and related microfluidic devices are provided for reducing dehydration of microfluidic devices during use. Microfluidic devices and related methods are provided with improved sample to reagent mixture ratio control. Microfluidic devices and systems are provided with improved resistance to compression fixture pressure induced failures. Methods and systems for conducting temperature controlled reactions using microfluidic devices are provided that reduce condensation levels within the microfluidic device. Methods and systems are provided for improved fluorescent imaging of microfluidic devices.

The present invention relates generally to microfluidic devices, which provide for precise control and manipulation of fluids that are geometrically constrained to a small, typically sub-millimeter, scale. In particular, the invention provides microfluidic devices and related apparatus, systems, and methods.
Recently, there have been concerted efforts to develop and manufacture microfluidic systems to perform various chemical and biochemical analyses and syntheses, both for preparative and analytical applications. The goal to make such devices arises because of the significant benefits that can realized from miniaturization with respect to analyses and syntheses conducted on a macro scale. Such benefits include a substantial reduction in time, cost and the space requirements for the devices utilized to conduct the analysis or synthesis. Additionally, microfluidic devices have the potential to be adapted for use with automated systems, thereby providing the additional benefits of further cost reductions and decreased operator errors because of the reduction in human involvement. Microfluidic devices have been proposed for use in a variety of applications, including, for instance, capillary electrophoresis, gas chromatography and cell separations.
Microfluidic devices adapted to conduct nucleic acid amplification processes are potentially useful in a wide variety of applications. For example, such devices could be used to determine the presence or absence of a particular target nucleic acid in a sample, as an analytical tool. Examples of utilizing microfluidic device as an analytical tool include:
testing for the presence of particular pathogens (e.g., viruses, bacteria or fungi);
identification processes (e.g., paternity and forensic applications);
detecting and characterizing specific nucleic acids associated with particular diseases or genetic disorders (e.g., fetal diagnostics);
detecting gene expression profiles/sequences associated with particular drug behavior (e.g., for pharmacogenetics, i.e., choosing drugs which are compatible/especially efficacious for/not hazardous with specific genetic profiles); and
conducting genotyping analyses and gene expression analyses (e.g., differential gene expression studies).
Alternatively, the devices can be used in a preparative fashion to amplify nucleic acids, producing an amplified product at sufficient levels needed for further analysis. Examples of these analysis processes include sequencing of the amplified product, cell-typing, DNA fingerprinting, and the like. Amplified products can also be used in various genetic engineering applications. These genetic engineering applications include (but are not limited to) the production of a desired protein product, accomplished by insertion of the amplified product into a vector that is then used to transform cells into the desired protein product.
While currently available microfluidic devices and related apparatus, systems, and methods provide for a wide range of uses, further improvements are desirable. In particular, it would be beneficial to reduce costs associated with the production and use of microfluidic devices. It would also be beneficial to provide improved processes for using microfluidic devices.


An X-ray computed tomography apparatus has a beam filter arrangement with regions of different filter material or/and different thickness profile of the filter material. This beam filter arrangement is disposed in the beam path preceding an examination subject. For multi-spectra beam hardening correction with estimation of the base material lengths, the computed tomography apparatus is fashioned for implementing projections of the examination subject with different effective material thickness or/and different effective material of the beam filter arrangement.

1. Field of the Invention
The present invention is directed to an X-ray computed tomography apparatus with multi-spectra beam hardening correction.
2. Description of the Prior Art
The attenuation p that X-radiation generated by an X-ray source experiences in a transirradiated subject is measured in X-ray computed tomography. It is determined from the X-ray intensity I0 incident onto the subject and from the intensity I that is registered in a detector arranged in the beam path following the subject, according to the following equation:
p=xe2x88x921n(I/0)xe2x80x83xe2x80x83(1).
In the case of mono-energetic radiation, the following applies for a homogeneous subject with the attenuation coefficient xcexc and the transirradiated subject thickness d:
p=xcexcd xe2x80x83xe2x80x83(2).
The X-ray attenuation thus increases linearly with the subject thickness.
In fact, however, an X-ray tube emits polychromatic X-radiation with the energy distribution S(E). The attenuation is then calculated according to the following equation:
p=∫xc2x7∫xcexc(E)S(E)dEdxxe2x80x83xe2x80x83(3).
Even when the subject is homogeneous, the X-ray attenuation produced by the subject is thus no longer linearly dependent on the transirradiated subject thickness. Since xcexcE usually decreases toward higher energies, the xe2x80x9cenergy center of gravityxe2x80x9d shifts toward higher energies, namely all the more the greater the transirradiated subject thickness is. This effect is referred to as beam hardening.
In image reconstruction methods that are standard in CT technology, a linear change of the X-ray attenuation with the subject thickness is assumed for homogeneous subjects. The overall attenuation p of a beam on its path through a subject composed of partial subjects i with attenuation coefficient xcexci and thickness di then derives from:
p=xcexa3i(xcexcidi)xe2x80x83xe2x80x83(4)
The deviations from this assumption caused by the beam hardening lead to data inconsistencies and, thus, to image errors. Typical image errors caused by beam hardening are key artifacts in large, homogeneous subjects and line or bar artifacts in CT images with a high proportion of bone or contrast agent. Current correction methods often have the principal goal or eliminating key artifacts and stripe artifacts in subjects with high attenuation, for instance in shoulder and pelvis exposures. These corrections usually ensue with what is referred to as polynomial correction, whereby a corrected attenuation value pc is calculated from a detected measured attenuation value pM by insertion into a polynomial with predetermined coefficients an according to the following equation:
pc=xcexa3[n=0.1 . . . N](anPMn)xe2x80x83xe2x80x83(5).
The coefficients an are acquired, for example, by measuring the attenuation values of uniform absorbers (for example, Plexiglas(copyright) bars) given N different thicknesses.
It has been shown that improved correction methods are needed for the correction of locally limited bar and line artifacts as well as unsharp bone-tissue transitions as particularly occur given skull exposures (another known stripe artifact, for example, is what is referred to as the Hounsfield stripe between the petrous bones). An approach has thereby proven beneficial wherein the length of the xe2x80x9cbase materialxe2x80x9d that the X-ray beam leading to a measured value has traversed in the body of the patient under examination is individually estimated for each measured attenuation value. In medical examinations, bone substance and soft tissue or, respectively, water, which has spectral attenuation properties similar to soft tissue, are usually selected as base materials. A method referred to as the two-spectra method, for example, is known from the pertinent literature for estimating the base material lengths traversed by an X-ray beam. In this method, two measured values with respectively different spectral energy distribution of the X-ray, which is equivalent to a different average energy of the X-ray, are registered. Given known attenuation coefficients xcexcW(E1) and xcexcW(E2) of water at the average spectral energies E1 and E2 and xcexcK(E1) and xcexcK(E2) of bone at these average energies, the following, approximate estimate is possible for the measured attenuation values p(E1) and p(E2) obtained given there energies E1 and E2:
p(E1)=dWxc2x7xcexcW(E1)+dKxc2x7xcexcK(E1)xe2x80x83xe2x80x83(6a)
p(E2)=dWxc2x7xcexcW(E2)+dKxc2x7xcexcK(E2)xe2x80x83xe2x80x83(6b).
The water and bone lengths dW and dK can then be estimated from these equations.
Corrected measured values pc(E1) or, respectively, pc(E2) can now be respectively determined in the following way for the average spectral energies E1 and E2:
pc(E1)=p(E1)+fE1(dW,dK)xe2x80x83xe2x80x83(7a)
pc(E2)=p(E2)+fE2(dW,dK)xe2x80x83xe2x80x83(7b)
The correction values fE1 and fE2 are taken from tables that were determined in advance either computationally or empirically for the average spectral energies E1 and E2.
Further information about the above two-spectra method can be found, for example, in the following publications:
1) P. M. Joseph, R. D. Spiftal, Journal of Computer Assisted Tomography, 1978, Vol.2, p.100;
2) P. C. Johns, M. Yaffe, Medical Physics, 1982, Vol.9, p.231;
3) G. H. Glover, Medical Physics, 1982, VOl.9, p.860;
4) A. J. Coleman, M. Sinclair, Physics in Medicine and Biology, 1985, Vol.30, No.11, p.1251.
In order to register measured values at two different average energies in a conventional CT apparatus, two successive revolutions of the X-radiator around the patient must be implemented. In the second revolution, a different beam prefiltering or a different tube voltage is used compared to the first revolution. A disadvantage of such a procedure, however, is that the measured results can exhibit inconsistencies due to patient movement or contrast agent flow.
It is an object of the present invention to provide a computed tomography apparatus which avoids the aforementioned disadvantages of conventional computed tomography systems.
This object is achieved in accordance with the principles of the present invention in an X-ray computed tomography apparatus having an X-ray radiator with at least two spring foci between which the X-ray radiator is switched to alternatingly emit X-ray beams respectively from the foci, a radiation detector disposed in the X-ray beams, with an examination subject adapted to be disposed between the X-ray radiator and the radiation detector, the radiation detector having a number of detection channels, a beam filter arrangement disposed in said X-ray beams preceding said subject, the beam filter arrangement having regions of different filter characteristics respectively allocated to the foci to give the X-ray beams respectively different energies that the subject, and wherein the X-ray radiator irradiates a slice of the subject with the X-ray beams from a number of projection angles with the X-ray beams, after attenuation by the subject, being incident on detector channels of the radiation detector in a projection range. The radiation detector, for each detector channel in the projection range, generates at least two measured projection values for the respective X-ray beams at different energies from the foci. The measured projection values are supplied to an electronic and evaluation reconstruction unit connected to the radiation detector, which determines a beam hardening-corrected projection value for each of the measured projection values, and reconstructs a tomographic image of the slice of the examination subject using these corrected projection values.
The different regions of the filter arrangement achieve the aforementioned different energy-influencing filter characteristics by being of different filter material, or being of the same filter material but having respectively different thickness profiles in the regions.
The varying material or/and the varying material thickness of the beam filter arrangement make it possible to realize different average energies of the X-rays entering into the examination subject with a single beam filter arrangement without having to change the beam filter arrangement. In particular, the projection measured values for the various average energies can be registered in immediate chronological proximity to one another, so that falsifying influences on the projection measured values due to contrast agent flow and physical movements on the part of the patient area voided. All projection measured values can then be registered in one revolution of the radiator of the radiator-detector arrangement.
Since a multi-spectra correction with estimate of the base material lengths will not be required in all examination scenarios, it is recommended that the beam filter arrangement be interchangeably mounted at the radiator-detector arrangement in order to also keep the employability of the computer tomography apparatus opened for other correction techniques as well.
The beam filter arrangement can be held in a simple way at a diaphragm carrier arranged radiator-proximate that carries a diaphragm arrangement for beam shaping of the x-radiation emitted by the radiator.
The evaluation and reconstruction unit can be fashioned for determining an effective projection value by weighted summation from corrected projection values determined in allocation to respectively one of the detection channels and respectively allocated to one of the spring foci and for reconstructing the tomographic image upon employment of the effective projection values. In this way, the effect can be compensated that the projection measured values of a detection channel are registered at different spectra.
The spring focus mode, however, also allows for the possibility of realizing slice projections of enhanced sampling density by fashioning the evaluation and reconstruction unit for reconstructing the tomographic image for a plurality of projection channels per slice projection that is equal to a multiple of the plurality of detection channels lying within the projection region of the respective slice projection corresponding to the number of spring foci. The evaluation and reconstruction is fashioned for employing the corrected projection values determined in allocation to respectively one of the detection channels for all spring foci in the reconstruction of the tomographic image as corrected projection values of neighboring projection channels.
The inventive also can be advantageously utilized in computed tomography devices wherein the detector of the radiator-detector arrangement is implemented with a number of detector elements arranged in at least two lines lying above one another, an identical detection channel being allocated to their detector elements lying above one another in a respective column. In this case, the beam filter arrangementxe2x80x94in allocation to at least a sub-plurality of at least two detector elements of each column of detector elements lying within the projection region of a slice projectionxe2x80x94can respectively comprise a region of different filter material or/and different thickness profile of the filter material. The radiator-detector arrangement is then fashioned for supplying a respective projection measured value for each detector element from this sub-plurality of detector elements in allocation to each column of detector elements lying within the projection region of this slice projection.
In order to avoid subjectively perceived changes between tomographic images based on the employment of different energy spectra that are reconstructed from the projection measured values of successive lines of detector elements, the evaluation and reconstruction unit can be fashioned for determining an effective projection value by weighted summation from the corrected projection values determined in allocation to respectively one of the columns and respectively allocated to one of the detector elements from the decreased number of detector elements and of reconstructing the tomographic image using the effective projection values.

X-ray computed tomography apparatus and multi-spectra correction using a radiation pre-filter


An apparatus for collecting liquid leaks, the apparatus comprising a tub, at least one boot for sealing a pipe passing through the tub for preventing leakage of the tub from water leakage collected in the tub from either a fluid reservoir disposed above the tub or leakage dripping along the pipe.

Water damage can be devastating to the integrity of a building. Often, even a small volume water leak can cause damage to either shelters or personal belongings. Several attempts have been made to develop systems to safeguard household structures using various water collection basins for collecting leaking water as well as alarm systems to notify owners when a leak does occur. Amongst the pitfalls of existing water leak detectors is the fact that there is commonly an area not covered by the basin to allow drainage pipes to pass through. Therefore, there is a need for a leak prevention apparatus that is allowing the piping system to pass through the collection tub to collect dripping from the piping system.

System and method for detecting and containing liquid leaks


A cooler box or container for containing a one or more bottles for storing human breast milk or infant formula. The container includes four sidewalls and a floor defining an internal volume, and a closure is configured to enclose the internal volume and prevent or provide access thereto. The container is size and shaped for fitting in a stacked arrangement within a refrigerator or freezer, and is easily transportable while keeping the internal volume at a low temperature to prevent the breast milk within the one or more bottles from spoiling. In example embodiments, the container 10 provides for multiple functions throughout its usable life such as functioning as a shipping box or container, a user transport device, and a storage bin in hospital or medical facility refrigerator.

Coolers are commonly used to store food and beverage items that must be kept at low temperatures to prevent spoilage. Coolers are available in various sizes and shapes from the large hard-sided insulated chests to the individual soft-sided lunch sacks. These coolers are designed for the sole purpose of keeping perishable foodstuffs cold, and for example, to provide a container that is generally capable of being easily transportable. Coolers generally have walls defining an interior cavity into which the foodstuff is placed. The walls are usually made of or contain an insulating material such as foam or air.
Specific concerns occur when transporting human breast milk or infant formula between hospital visits and the mother's home, and during storage and use at the hospital. For example, in most cases, at the hospital and with the child feeding regularly, not all of the human breast milk is needed at once, and thus the cooler must be substantially insulated to keep the breast milk cool or the cooler (with the breast milk contained therein) must be kept at a low temperature to keep the breast milk from spoiling.
Typically, known coolers are either small, compact and lack sufficient insulation, or they are substantially large and bulky and generally have sufficient insulation to keep the breast milk at a low temperature. Thus, coolers capable of fitting within a refrigerator or within another cooling device (e.g., small and compact) generally lack the insulation or thermal capabilities to maintain the breast milk at a low temperature during transportation. And, in contrast, larger bulky coolers can generally maintain the breast milk at a lower temperature (for a longer time compared to the small and compact coolers) are substantially too large for fitting within a refrigerator or other cooler.
Needs exist for improved containers and coolers for containing and transporting human breast milk or infant formula. It is to the provision of a collection and feeding bottle container meeting these and other needs that the present invention is primarily directed.