A pitted light diffusive coating having an excellent light diffusion effect and a method of forming the coating and a halogen lamp with the coating are disclosed. The light diffusive coating includes pits on the surface of a continuous coating consisting of a metal oxide formed on a base, and the coating is substantially free of bubbles. The pitted light diffusive coating is formed by coating a base with an organometallic compound and a high boiling-point organic solvent and baking the coating at about 400.degree. C. to 500.degree. C. The halogen lamp has a pitted light diffusive coating formed on an infrared reflective coating on the surface of the outer vessel. Strain, caused by the difference in the thermal expansion coefficient of the structural material of the outer vessel and the structural material of the light diffusive layer occurring when the outer vessel is at a high temperature, is absorbed by the pitted structure, and peeling is prevented.

1. Field of the Invention
The present invention relates to light diffusive coatings which are formed on the base surface of lamps such as halogen lamps and high pressure discharge lamp bulbs, and optical fibers and window glass, etc., and to methods of forming such coatings.
2. Discussion of the Background
To obtain a uniform distribution of illumination over the illuminated surface, halogen lamps for photocopiers, for example, have several filaments connected in series through conductors, and the whole assembly is enclosed in a straight tube type outer vessel made of silica glass so that it lies along the axis of the tube. However, because this halogen lamp includes a large amount of infrared radiation in its emissions, there is a danger that the item being photocopied will be damaged by the heat. For this reason, the lamp surface generally undergoes a honing treatment to provide a diffusive surface.
This method, however, has the disadvantage of being very laborious. In addition, the methods of forming a light diffusive coating by applying a fine diffusive powder such as silica to the outside of the lamp by electrostatic coating and etching may be considered. These types of coating are generally weak for mechanical stresses, wear easily, and in some cases the light diffusive effect falls off over long periods of use. Depending on the type of fine light diffusive power, there are cases in which the coating has a poor affinity for the quartz glass, and readily peels off.
With regard to these points, the inventors have previously developed the technology of forming a coating on the outer surface of the transparent outer vessel which allows visible light to pass through, but reflects infrared light, and by providing a light diffusive coating on top of the infrared reflective coating, the visible light which has passed through the infrared reflective coating is dispersed by the light diffusive coating, giving a uniform distribution of illumination on the illuminated surface. This was proposed in the Japanese Patent Application Number Sho 58-95001(95001/1983).
However, when this technology is applied to lamps, such as halogen lamps for example, because the temperature of the lamp's outer vessel is extremely high, with some light diffusive coatings there is the danger that the light diffusive coating may peel off due to the effect of repeated switching on and off over a long period of time. This means that it is essential to select a light diffusive coating which is stable regardless of the rise and fall in temperature and which is mechanically strong.
A light diffusive coating which includes bubbles and pits within a layer of metal oxide and a method for forming such a coating is disclosed in Japanese Patent Applications P59-203672 and P59-203673 and U.S. Pat. No. 4,721,877 and U.S. patent application Ser. No. 07/098,884. Although the disclosed coating provides a high diffusiveness, the presence of the bubbles decreases the light transmission and mechanical strength of the coating.
Thus, there remains a need for a light diffusive coating with improved light transmission and mechanical strength while maintaining adequate light diffusion. In addition there is a need for a method of production of such a light diffusive coating.

Pitted light diffusive coating, a method of forming the coating and a lamp having the coating


A transmitting device generates a data block including a first field having a first plurality of bits that includes an error detection portion and a second field having a second plurality of bits; selects an error injection mask based on the second plurality of bits; modifies the first plurality of bits with the error injection mask to generate a modified first plurality of bits; and transmits the data block to a receiving device. The receiving device decodes the second plurality of bits to generate decoding results; selects an error injection mask based on the decoding results; modifies the first plurality of bits using the error injection mask to generate a modified first plurality of bits that includes a resultant error detection value indicated in the error detection portion; and detects whether the decoding results for the second field are correct based on the resultant error detection value.

When communicating data blocks between transmitting and receiving devices in a communication system over a wireless interface, typically some type of error detection and error correction mechanism is used to assist in the decoding of each data block at the receiving device for enabling further processing of the data block. Herein, a data block is generally defined as a block of continuous bits containing information and/or signaling, and decoding is defined as the initial processing of a received data block to identify the received bits (e.g., as 1s or 0s) and may include, detecting and/or correcting errors in the received bits. Signaling is concerned with the establishment and control of connections in a network.
Generally, a data block has a predetermined logical structure having a plurality of different types of fields for organizing the bits in the data block, and one or more or these fields may contain bits that enable the error detection and/or error correction for that field. However, depending on the protocol used, some fields may include error correction bits but not error detection bits or limited error detection bits because of a bit number constraint due to, for instance, bandwidth constraints associated with the physical channels over which the data block is sent. A resulting limitation is that an inability to detect decoding errors in some fields can cause fairly substantial problems related to the further processing of the data block if there are, in fact, errors that go undetected.
An example of an air interface protocol that has a data block structure that includes fields having error correction but not error detection is the air interface protocol defined in accordance with the ETSI (European Telecommunications Standards Institute) TS (Technical Specification) 102 361-1. A data block structure identified in this technical specification is a burst, which is defined as the smallest predefined block of continuous bits containing information or signaling. More particularly described therein is a DMR (Digital Mobile Radio) TDMA (Time Division Multiple Access) burst. The DMR TDMA burst includes, for instance, a Data Type field that identifies the type of data being transmitted in an Information field, which is also included in the burst. There are a number of data types mentioned in the technical specification including, e.g., Voice LC Header, Terminator with LC, CSBK, Data Header, etc. Since this field is subject to error correction (in this case forward error correction (FEC), which is well known in the art) but not error detection, it is not possible for a receiver to know whether the error correction on the Data Type field was successful. Because of this, it may be possible under certain error conditions for some burst types to be processed incorrectly.
For illustrative purposes, following are two examples of problems that may arise due to a failure to detect an incorrectly identified data type. In one example, a CSBK could mistakenly be interpreted as a Data Header (which is a first burst of a multi-burst data message), due to uncorrectable errors on the channel. Since a Data Header contains a Blocks to Follow field specifying how many additional bursts belong to this transmission and a CSBK does not, the receiver treats the subsequent bursts as part of that data transmission. Accordingly, other transmissions, such as new voice transmissions, CSBKs, and new data transmissions, are missed during this period.
As another example, a Terminator with LC could mistakenly be interpreted as a Voice LC Header. As many Terminator with LC bursts are typically transmitted during Call Hangtime, the potential side effects include causing a receiver to begin processing a new voice transmission when none exists.
Therefore, it is desirable to have a method and apparatus to provide reliable error detection for a field without or with limited bits reserved for error detection.

Method and apparatus for error detection in a data block


A vehicle tire deflator comprising a foldable and extendible frame with one or more rocker arms releasably carrying hollow spikes and having rocker arm actuators attached to the rocker arms to pivot said arms to position the spikes to enter a tire rolling over the deflator and to hold the rocker arm in position as the spike is withdrawn from the rocker arm.

1. Field of the Invention
This invention relates to devices for use by police and the like to deflate the tires of a vehicle being operated by fleeing persons.
2. Prior Art
It is well recognized that police officials from time to time find it necessary to stop the vehicle being operated by persons who are fleeing or attempting to avoid being stopped.
Portable barricades have often been used in attempts to stop a vehicle. The blockade may be framed structures but often a portable barricade is formed with police vehicles placed to extend transversely across a roadway. It is not uncommon, however, that fugitives will attempt to drive through a blockade of saw-horse type or other framed structures or around or even through a blockade of vehicles. Naturally, there is a potentially high element of danger to police officers manning a road block and the cost is very high should a fugitive attempt to crash his vehicle through a barricade, particularly if the barricade is made of police vehicles.
Generally, also, it requires a large number of police personnel to set up and man a road blockade.
The need for a means of disabling a vehicle that can be established and manned by even a single police officer and that will effectively disable a vehicle containing one or more fleeing individuals has been recognized in the past. Thus, in U.S. Pat. No. 4,382,714, there is disclosed a vehicle disabling means in the form of a plurality of hollow, spike-like devices adapted to project perpendicular to a road surface to puncture one or more tires of a fleeing vehicle. A plurality of the devices may be interconnected to facilitate placement and to create a flailing effect within the wheel well of the vehicle.
Other tire puncturing devices, using hollow needles arranged to point vertically upwardly or upwardly at an angle and supported by metal bars or heavy canvas and/or rubber mats have also been known.


An air conditioner provided with a refrigerant circuit formed by connecting with piping a refrigerant compressor, a condenser, an expansion means and an evaporator, an inverter power supply means for controlling the rotational speed of an electric motor for driving the refrigerant compressor, a load detector, and a controller for controlling the inverter power supply means on the basis of an output from the load detector. A refrigerant flow passage controlling mechanism is provided to change the rate at which the refrigerant flows through the condenser on the basis of a control command from the controller, thereby making it possible to reduce or increase the discharge rate without extending the range of changes in the rotational speed of the compressor. The compressor can be controlled according to a wide range of changes in the load to operate with an operation range which ensures high efficiency of the compressor operation.

This invention relates to an air conditioner the capacity of which can be controlled to be optimized with respect to a wide range of changes in the load.
Conventionally, methods for controlling air conditioners according to changes in the load were developed, including one adopted for air conditioners having a multi-cylinder reciprocating compressor and based on changing the number of effective cylinders (unloading), and one based on changing the number of poles of the motor by changing over connections thereof from the outside to select the operating speed of the compressor.
Thereafter, with development of rotating type compressors such as rotary compressors and scroll compressors, inverter driving systems for selecting the rotational speed of the compressor by changing the frequency of the current for power supply to the compressor driving motor have been put to practical use. A type of air conditioner, such as the one disclosed in Japanese patent Unexamined Publication No. 63-140884, having a scroll compressor with an inverter driving system has been proposed prior to the present invention. Specifically, in FIG. 6 of this publication, a refrigerant circuit of an air conditioner having an inverter driving system is illustrated which is composed of a scroll compressor, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger. A refrigerant circulation passage is reversed for cooling or heating operation by a four-way change-over valve provided in the refrigerant circuit. The speed at which the scroll compressor is rotated can be changed by an inverter interposed between an ac power source and a motor for driving the compressor. The frequency of the driving current output from the inverter is controlled according to the indoor cooling load or heating load. Ordinarily, when the compressor rotates at a low speed, it operates at a low pressure ratio, that is, the discharging pressure is low while the drawing pressure is high or, when the compressor rotates at a high speed, it operates at a high pressure ratio, that is, the discharging pressure is high while the drawing pressure is low.
To change the capacity of the air conditioner in response to a change in the load, the discharge rate of the compressor may be changed. However, in a case where a reciprocating compressor is controlled by the method of changing the rotational speed of the compressor with the inverter, the range of changes in the rotational speed is restricted due to vibrations of a reciprocating member and noise generated therefrom. In the case of a rotating type compressor such as a rotary or scroll compressor, the range of changes in the rotational speed is comparatively extended. With development of multiple room air conditioners for air-conditioning a plurality of rooms, however, there is a need for a further improvement in the capacity variation range.
To meet this requirement, the range of changes in the rotational speed of the compressor may be extended by extending the range of frequencies with which the driving current is supplied from the inverter to the compressor. During high speed operation, however, problems relating to the strengths of mechanical parts and to the reliability of the bearing are encountered because the load increases as centrifugal forces applied to movable parts increase, and the problem of increases in mechanical and fluid losses are also encountered resulting in a reduction in the efficiency such that a larger input is required for the same work. During low speed operation, the following problems are encountered. That is, the rate at which the refrigerant gas leaks out of the compression space is increased, resulting in a reduction in the efficiency. It is difficult to form the desired oil film on the sliding portion and, hence, to achieve the desire reliability. In the case of a compressor with a lubrication oil pump utilizing a centrifugal force, it is difficult to maintain the desired oil supply rate.
Thus, it is undesirable to design the compressor to extend the capacity variation range only by extending the range of changes in the rotational speed of the compressor.


A manually operable and steerable curb extrusion device for extruding curb, barrier, wall, gutter or the like from concrete, cement or some other moldable building material. The curb extrusion device has a segmented vibrating hopper into which building materials are placed to fall onto two tapered counter rotating vibrating augers which compact and force the building material through an extrusion mold where it is shaped before extrusion.

1. Field
This invention relates to concrete curb forming and extruding apparatus. More particularly, it relates to a concrete curb forming and extruding apparatus with wheel adjustment locks, a slip form for the curb cross-section, and a straight-up side for getting close to vertical surfaces, with an extruder having a hopper with a flexible liner, augers rotating in opposite directions to compact the concrete, and a flexible member between the compaction chamber and the slip form to isolate the vibration.
2. State of the Art
Present concrete curb forming and extruding machines have a compaction member, such as a reciprocating ram or an auger to force concrete material into a slip form forming a running curb. The concrete material is usually of a dry consistency to hold the form of the curb after being extruded from the machine. The dry consistency of the material causes it to bridge from side to side in the hopper and not fall through into the compaction chamber. It is common practice to have two men run the machine-one to steer and control the machine while the other shovels small amounts of material into and through the hopper.
The ram type of curb forming and extruding machines use a gear box to reduce the speed with a crank arm connected to a flat faced member which is pushed by the crank through the compaction chamber or housing displacing the curbing material through the slip form to form the curb. May, U.S. Pat. No. 4,566,823 is an example of a manually operable curb extrusion device with interchangeable molds and compacting members wherein building material is placed in a receiving hopper and falls into a compacting chamber where a power driven and reciprocating compacting member compacts the material into the extrusion mold where it is shaped and extruded. The curb extrusion device is manually directed or steered along the desired course via an adjustable steering mechanism, and has a hopper with one straight upright side, screw-on molds, and adjustable legs connected to the wheels. Eggleton, U.S. Pat. No. 4,310,293 is another example of a ram driven concrete curb molding apparatus.
Ram machines have been the most popular because of their positive travel. However, straight compressive forces are not conducive to better compaction. Varying sizes of particles resist compaction and stack one against another, leaving voids or cavities between the particles. Voids cause porous concrete with diminished compressive test strengths. The ram of the ram curb forming machine also picks up some of the concrete material on the return back-stroke which is then deposited as a trail of material down the sides of the curb as waste. This slag has to be cleaned up or pressed down out of sight and buried. Ram machines, as the speed of the ram is increased, tend to jump ahead and then coast forward at the end of the stroke which pulls cracks in the top surface of the curb. Loose parts on the machine, such as wheels, can also leave marks in the extruded curb.
Auger type curb forming machines use an auger to move material through a compaction chamber into the slip form, are not as positive as the ram machines. They will not travel as effectively up and down hills. The auger applies pressure for compaction and forces material through the mold rearward, thereby propelling the machine forward. If the material becomes captive and turns with the auger, pressure is required to propel the machine. The compacting chamber, thus filled, causes wear and power consumption with little forward propulsion pressure being created. Smith, U.S. Pat. No. 3,137,220 discloses a curb-laying machine with a number of oppositely rotating augurs to extrude the concrete for forming curbs. Parrish et al., U.S. Pat. No. 5,018,955 utilizes a single auger to extrude the concrete and features a slip-on curb form with various adjustment options. Other examples of curb forming machines employing an auger are: Bunn, U.S. Pat. No. 4,548,565, Coho. Jr. et al., U.S. Pat. No. 3,915,584, W. E. Canfield et al,., U.S. Pat. No. 2,818,790. None of these devices avoids the augering captive material problem.
Cited for general interest are: Aparicio, U.S. Pat. No. 3,915,583 disclosing a paving machine slip form, Baucum. U.S. Pat. No. 4,298,293 disclosing a drag line operated slip form curb forming machine, and Leone, U.S. Pat. No. 4,984,932 disclosing an apparatus for continuous formation of concrete curbs via the raising and lowering of the molding to form thresholds for driveways, and intermediate tapering sections for transitions between full height curbs and thresholds.
The present invention overcomes above problems and provides an improved curb forming and extruding machine with a constant even flow of material without requiring an additional person to feed it. It also provides a curb having strong compressive strength with a smooth finished look not requiring manual troweling.


A phase-contrast x-ray computed tomography scanner, a monochromatic diffraction computed tomography scanner, a rotatable monochromatic diffraction computed tomography scanner, and a combination phase-contrast and monochromatic computed tomography scanner are provided. In addition, a method of identifying an unknown sample is provided.

1. Field of the Invention
The present invention relates generally to the fields of radiography and tomography. More particularly, this disclosure describes how a standard x-ray source may be used to create phase-enhanced computed tomography (CT) images. These phase-enhanced CT images provide sharper images which make small edges, including small masses or small spiculations, more evident. This provides a method for, among other things, the inspection of organic materials and for use in medical apparatuses.
2. Description of Related Art
In the conventional x-ray transmission imaging system, the contrast of an obtained image depends upon the degree of absorption of x-rays by an object. Namely, if there is a region where heavy elements with high x-ray absorptance are dense, that portion exhibits a low transmittance and can be caught as a shadow in an image. On the other hand, objects made of light elements (soft tissues, etc.) are transparent to x-rays and are therefore difficult to obtain an image contrast. For example, in many clinical situations, such as mammography, there is a need to distinguish between different kinds of soft tissue, between tumors and normal tissue, for instance. Accordingly, there is employed a method in which the contrast is emphasized by injecting heavy elements as a contrast agent in order to observe biological soft tissues (such as internal organs, tumors, or blood vessels), for example, when an x-ray cross section image for medical diagnosis is to be acquired. However, the contrasting technique cannot always be applied to all observation locations to be investigated. Also, the contrasting process may negatively impact the body.
The above problem concerning the image contrast exists similarly even in x-ray computerized tomography (CT) which is a three-dimensional, inside-observing technique. A CT scanner x-rays the body from many angles. The x-ray beams are detected by the CT scanner and analyzed by a computer. The computer compiles the images into a picture of the body area being scanned. These images can then be viewed on a monitor or reproduced as photographs.
In lieu of x-ray absorption techniques, there is an imaging method available for obtaining a contrast by monitoring x-ray phase shifts. A phase-contrast x-ray records information from the x-ray beams after they have passed through different materials, including biological soft tissues. All tissues cause the x-rays to slow down, resulting in what is known as a phase shift. The size of the shift depends on the type of tissue. Phase-sensitive techniques, which can be understood using wave optics rather than ray optics, offer ways to augment or complement standard absorption contrast by incorporating phase information. Also, since phase-contrast relies only on refraction of x-rays, not on absorption, imaging can be done at higher energies where the absorbed radiation dose can be less, thereby reducing potential damage to tissues.
The use of phase-contrast imaging methods enables observation with an excellent sensitivity which is one-thousand times as high as that in the conventional absorption-contrast method. Thus it may be possible to observe phase contrast when absorption contrast is undetectable. Furthermore, biological soft tissues can be observed without being subjected to a specific contrasting process. Also, even if a contrast agent is used, the choice of a wider variety of contrast agents and contrasting techniques are possible.
There has been devised a phase-contrast x-ray CT apparatus in which phase contrast is introduced to the x-ray CT enabling three-dimensional observation. U.S. Pat. No. 5,173,928 is specifically incorporated herein by reference in its entirety. According to the disclosed technique of the '928 patent, an x-ray interferometer is used to reconstruct an image in a virtual-cross section from interference patterns. This disclosed technique is limited to observing an object having a diameter of only several millimeters, and therefore is not practical for medical diagnosis. Further problems with the above system using the x-ray interferometer is that (1) in order to ensure coherency, the energy band of an x-ray beam must be narrowed to obtain a high monochromaticity and hence a bright light source such as synchrotron radiation must be used; and (2) that a precision optical system is required and it is therefore difficult to handle the system.
There has also been devised a phase contrast x-ray CT apparatus in which an x-ray interferometer is not used. U.S. Pat. No. 5,715,291 is specifically incorporated herein by reference in its entirety. In the '291 patent, the phase distribution is determined from the distribution of refraction angles of x-rays transmitted through an object. However, this disclosure is limited to object rotation to acquire the necessary data to reconstruct a CT image.
In view of the shortcomings such as those listed above, improved phase-contrast imaging techniques would be desirable.

Phase-contrast enhanced computed tomography


A shower valve assembly configured to divert water between a tub port and a shower port. The diverter valve assembly position or state is changed by pushing a button connected to a stem and a poppet valve. When the water supply is turned off, a poppet spring shifts the poppet valve to a tub open position, and a check valve spring opens a check valve, allowing water from the shower port to flow out of the tub port.

The present invention relates generally to a faucet diverter valve and, more particularly, to a push-button diverter valve for tub/shower applications.
Push-button flow diverter valves for tub/shower applications are often desirable for their appearance and ease of use. By incorporating the diverter valve into a main valve, a separate diverter rough and trim are not needed, thereby reducing cost and improving installation efficiency. Also, if the diverter valve is not incorporated into the tub spout, the tub spout design can be simpler, sleeker, and less expensive.
According to an illustrative embodiment of the present disclosure, a shower valve assembly includes a valve body, a main or mixing valve cartridge to control water temperature and flow, and a diverter valve cartridge to control water flow to at least two outlet ports. The shower valve assembly may also include hot and cold water supply stops to allow the water to be shut off at the shower valve assembly instead of shutting off water to the whole structure, floor, or unit, when servicing is required.
According to an illustrative embodiment of the present disclosure, a shower valve assembly includes a valve body including a first receiving cavity and a second receiving cavity. A cold water inlet port, a hot water inlet port and a connecting outlet port are in fluid communication with the first receiving cavity. A connecting inlet port, a first outlet port and a second outlet port are in fluid communication with the second receiving cavity. The connecting inlet port is in fluid communication with the connecting outlet port via a connecting waterway. A mixing valve assembly is supported within the first receiving cavity, the mixing valve assembly configured to control water flow from the cold water inlet and the hot water inlet to the connecting outlet port. A diverter valve assembly is supported within the second receiving cavity, and is configured to control water flow from the connecting inlet port to at least one of the first outlet port and the second outlet port. The diverter valve assembly includes a push-button, and a valve stem extending along a longitudinal axis between a first end and a second end, the first end being operably coupled to the push-button. The diverter valve assembly further includes a flow control chamber, a first outlet valve seat supported within the flow control chamber, and a second outlet valve seat supported within the flow control chamber in axially spaced relation to the first outlet valve seat. A poppet valve is supported by the second end of the valve stem and is axially movable within the flow control chamber, the poppet valve including a poppet valve body defining an internal chamber, a first seal selectively engageable with the first outlet valve seat, a second seal in axially spaced relation to the first seal and selectively engageable with the second outlet valve seat, and a spring operably coupled to the second end of the valve stem and configured to bias the first seal toward the first outlet valve seat. A check valve is operably coupled to the poppet valve, the check valve including a movable valve member received within the internal chamber of the poppet valve body.
According to another illustrative embodiment of the present disclosure, a shower valve assembly includes a valve body including a connecting inlet port, a first outlet port, and a second outlet port. A diverter valve assembly is configured to control water flow from the connecting inlet port to at least one of the first outlet port and the second outlet port. The diverter valve assembly includes a push-button, and a valve stem extending along a longitudinal axis between a first end and a second end, the first end being operably coupled to the push-button. A flow control chamber receives the second end of the valve stem. A first outlet valve seat is supported within the flow control chamber, and a second outlet valve seat is supported within the flow control chamber in axially spaced relation to the first outlet valve seat. A poppet valve is supported by the second end of the valve stem and is axially movable within the flow control chamber, the poppet valve including a poppet valve body defining an internal chamber, a first seal selectively engageable with the first outlet valve seat, and a second seal in axially spaced relation to the first seal and selectively engageable with the second outlet valve seat. A check valve is operably coupled to the poppet valve, the check valve including a first check valve seat supported within the internal chamber of the poppet valve body, a second check valve seat supported within the internal chamber of the poppet valve body in axially spaced relation to the first check valve seat, and a valve member received within the internal chamber of the poppet valve body. The valve member of the check valve is movable from a first position in contact with the first check valve seat, a second position in contact with the second check valve seat, and a third position intermediate the first position and the second position. A first mode of operation is defined when the connecting inlet port is in fluid communication with the first outlet port, and the connecting inlet port is sealed from the second outlet port. The first seal of the poppet valve body engages the first outlet valve seat, and the valve element of the check valve engages the first check valve seat in the first mode of operation. A second mode of operation is defined when the connecting inlet port is in fluid communication with the second outlet port, and the connecting inlet port is sealed from the first outlet port. The second seal of the poppet valve body engages the second outlet valve seat, and the valve element of the check valve engages the second check valve seat in the second mode of operation. A third mode of operation is defined when the second outlet port is in fluid communication with the first outlet port. The valve element of the check valve is in the intermediate position in the third mode of operation.
According to a further illustrative embodiment of the present disclosure, a shower valve assembly includes a valve body having a first receiving cavity and a second receiving cavity. A cold water inlet port, a hot water inlet port and a connecting outlet port are in fluid communication with the first receiving cavity. A connecting inlet port, a first outlet port and a second outlet port are in fluid communication with the second receiving cavity. The connecting inlet port is in fluid communication with the connecting outlet port via a connecting waterway. A mixing valve assembly is supported within the first receiving cavity, the mixing valve assembly configured to control water flow from the cold water inlet and the hot water inlet to the connecting outlet port. A diverter valve assembly is supported within the second receiving cavity, and is configured to control water flow from connecting inlet port to at least one of the first outlet port and the second outlet port. The diverter valve assembly includes a push-button, and a valve stem extending along a longitudinal axis between a first end and a second end, the first end being operably coupled to the push-button. The diverter valve assembly further includes a flow control chamber, a first outlet valve seat supported within the flow control chamber, and a second outlet valve seat supported within the flow control chamber in axially spaced relation to the first outlet valve seat. A flow control valve is supported by the second end of the valve stem and is axially movable within the flow control chamber, the flow control valve being movable between a first position in engagement with the first outlet valve seat and a second position in engagement with the second outlet valve seat. A check valve is operably coupled to the flow control valve. A first mode of operation is defined when the connecting inlet port is in fluid communication with the first outlet port, and the connecting inlet port is sealed from the second outlet port. The flow control valve is in the first position, in engagement with the first outlet valve seat, and the check valve seals the first outlet port from the second outlet port in the first mode of operation. A second mode of operation is defined when the connecting inlet port is in fluid communication with the second outlet port, and the connecting inlet port is sealed from the first outlet port. The flow control valve is in the second position, in engagement with the second outlet valve seat, and the check valve seals the first outlet port from the second outlet port in the second mode of operation. A third mode of operation is defined when the check valve provides fluid communication between the second outlet port and the first outlet port.
Additional features and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrative embodiment exemplifying the best mode of carrying out the invention as presently perceived.


A communication device is provided for transmitting information incorporated into at least one message packet. The device includes components for encoding the message packet as a signal, which is afterwards transmitted and analyzed. The encoder assigns the message packet to correspond to a specific pulse width. The transmitter sends the signal across a channel. The processor parses the signal as corresponding to the specific pulse width subsequently decoded to obtain the message packet.

The invention relates generally to data encoding for information transmission, and more particularly to encoding using variable pulse width, phase frequency and/or amplitude.
Data communications between a Host and a Client may include using a modulator-demodulator (modem), which converts digital information to analog information and vice versa. Typically, the modem performs pulse conversion of binary data from higher layers. The binary data may reside at the Physical layer of the (seven layer) Open Systems Interface (OSI) model for physical linkage between the Host and Client for transmitted and received data. These seven layers include: a) OSI Layer 1—Physical, b) OSI Layer 2—Data Link, c) 081 Layer 3—Network, d) OSI Layer 4—Transport, e) OSI Layer 5—Session, f) OSI Layer 6—Presentation, and g) OSI Layer 7—Application.
Current transmission technologies use standard communication exchange protocols, which are based on binary transmission, in which (for positive logic) a "1" is represented as positive voltage and a "0" is represented as no voltage. The transmission is based on a system clock. Binary transmission over wire and wireless media has been exploited for many years.

Information transmitter with variable pulse width encoding

The United States of America as represented by the Secretary of the Navy


The hematocrit of blood (i.e., the percentage of whole blood volume occupied by red blood cells) perfusing a finger is determined by stimulating the finger with two current frequencies, one relatively high (e.g., 10 MHZ) and the other relatively low (e.g., 100 KHz). Voltages induced in the finger in response to the two current frequencies are then captured and separated into baseline and pulsatile components. The hematocrit is determined as a function of the ratio of the high frequency pulsatile component to the low frequency pulsatile component, multiplied by the ratio of the square of the low frequency baseline component to the square of the high frequency baseline component. The volume of blood perfusing the body part at which hematocrit is to be measured may be increased on each pulse by the application of external pressure to the finger, such as by applying a pressure cuff to the finger. Assemblages including two pairs of electrodes are used to effect the determination of hematocrit. The assemblages may also include a component for applying pressure to the body part at which hematocrit is measured.

1. Field of the Invention
This invention relates generally to devices and methods for noninvasive in vivo measurement of blood hematocrit and, more specifically, to devices and methods for such measurement that use impedance and pressure plethysmography.
2. Background of Related Art
The xe2x80x9chematocritxe2x80x9d of blood, which is defined as the percentage of whole blood volume occupied by erythrocytes (i.e., red blood cells), is an important measure of patient well being in cases of trauma, blood loss by disease, iron depletion in pregnancy, dietary iron deficiency, and a number of more specific medical conditions.
Hematocrit has traditionally been measured by centrifuging a column of blood, which has been extracted from the patient, in a glass tube, until the erythrocytes are compacted by centrifugal force to one end of the tube. The hematocrit is determined by measuring the length of the tube containing dark red material and dividing by the total length of the liquid column in the tube. These length observations are usually made visually, but are also made, in some cases, by automated optical means of various designs. Besides centrifugal hematocrit determinations, hematocrit is also derived and reported by various automated blood analyzers which count erythrocytes optically in unpacked blood. This erythrocyte count correlates with packed cell hematocrit and the derived hematocrit is reported.
It is noted that the above-described methods for obtaining hematocrit are invasive, that is they require that blood be removed from the patient in order to determine the hematocrit. A non-invasive method would be desirable because it would subject the patient to less pain and inconvenience and would preserve the patient""s blood for its normal functions.
It has long been recognized by biomedical researchers that the electrical impedance of blood varies with hematocrit and that, as a result of this relationship, it should be possible to derive hematocrit from the measurement of blood impedance. Hematocrit has been successfully determined by measuring the impedance of blood that has been extracted from the patient and placed in an impedance measuring cell of controlled dimensions, where a fixed volume of the blood is contained, maintained at a known temperature, and agitated to maintain uniform cell distribution. Examples of such successful measurements are given by Okada and Schwan in xe2x80x9cAn Electrical Method to Determine Hematocrits,xe2x80x9d IRE Transactions in Medical Electronics, ME-7:188-192 (1960) and by deVries et al. in xe2x80x9cImplications of the Dielectrical Behavior of Human Blood for Continuous Online Measurement of Hematocrit,xe2x80x9d Medical and Biological Engineering and Computing, pages 445-448 (1993) (hereinafter xe2x80x9cdeVriesxe2x80x9d). Like the centrifugal methods, these methods are invasive, however, and thus do not satisfy the need for a non-invasive hematocrit measurement. The impedance methods have, however, provided the inspiration for some ingenious inventions to measure hematocrit in-vivo and non-invasively.
The first in-vivo impedance measurement of hematocrit known to the inventors was reported by Yamakoshi et al. in xe2x80x9cNoninvasive Measurement of Hematocrit by Electrical Admittance Plethysmography Technique,xe2x80x9d IEEE Transactions, BMB-27, 3:156-161(1980). This measurement was made by immersing the finger of the test subject in a saline solution contained in a chamber fitted with impedance measuring electrodes. The electrolyte concentration of the saline solution was then varied by mixing in either water or more concentrated saline until the pulsatile variations of impedance caused by the increased volume of blood on each pulse were minimized. When this minimization of pulses occurred, the saline solution had the same resistivity as the blood in the pulsing arteries and this resistivity could be correlated against the known, previously determined relationship between resistivity and hematocrit.
U.S. Pat. No. 5,526,808 (hereinafter xe2x80x9cthe ""808 Patentxe2x80x9d), issued to Kaminsky and assigned to Microcor, Inc., the assignee of the present invention, describes another impedance method for measuring hematocrit noninvasively and in vivo. This method draws upon the observation that hematocrit determines the frequency vs. impedance profile of blood. In addition, the method of the ""808 Patent uses the pulsatile change of impedance in a finger or other limb of the body that occurs when each heartbeat pushes new blood into the organ where the measurement is made to separate the non-blood tissue impedance from the blood impedance.
The mathematical model upon which this method is based relies upon the assumption that, as blood pulses into a finger or other body part where the hematocrit measurement is being made, the admittance (i.e., the reciprocal of impedance) change that occurs is due to the increased volume of blood providing a new current path in parallel with the old current path present before the pulse occurs. Thus, the difference in admittance between baseline, when no new blood is in the limb, and during the pulse, when new arterial blood has entered the limb, is due to the new blood. The numerical value of this admittance difference is proportional to the volume of the new blood times the admittance of the new blood.
As shown in deVries, the admittance vs. frequency characteristics of blood have a characteristic shape that depends upon hematocrit. Comparing the shapes of either the magnitude or the phase versus the frequency of the admittance, derived for the pulsed blood, against known characteristic hematocrit-dependent shapes gives a measure of hematocrit. The known characteristic shapes can be derived from a database obtained from patients having hematocrits independently measured by the centrifugal method previously described.
U.S. Pat. No. 5,642,734 (hereinafter xe2x80x9cthe ""734 Patentxe2x80x9d), issued to Ruben et al. and assigned to Microcor, Inc., the assignee of the present invention, describes some additional methods to obtain in vivo hematocrit results. First, the ""734 Patent describes using pressurized cuffs, in various ways, to change the amount of blood in the organ (e.g., the finger) at which hematocrit is noninvasively measured. Second, the ""734 Patent describes a unique electronic system for driving electrodes attached to the body part under measurement and for deriving phase, as well as amplitude information from impedance measurements of the body part. Third, the ""734 Patent teaches the use of a neural network computer algorithm to relate measured impedance and other data to hematocrit based upon matching a database obtained from a number of prior measurements of patients with separately-determined hematocrits.
In the field of blood oxygen saturation measurement, as opposed to the field of blood hematocrit measurement that has been under discussion thus far, U.S. Pat. No. 5,111,817 (hereinafter xe2x80x9cthe ""817 Patentxe2x80x9d), issued to Clark et al., observes that the accurate measurement of blood oxygen saturation levels in arteries (SaO2) in a body part under measurement, such as a finger, is typically hindered by different blood oxygen saturation levels in capillaries (ScO2) in the body part. The ""817 Patent teaches a method for correcting measurements of SaO2 for the effects of ScO2. In this method, a pressure cuff applies a pressure to the body part under measurement that is equal to the mean arterial blood pressure in the body part. As a result, measurements from the body part are dominated by the effects of the actual SaO2 in the body part, so that the measured SaO2 is closer to actual SaO2.
While the use of pressure cuffs are known in the art to assist in the noninvasive measurement of hematocrit and blood oxygen saturation, as is the use of electrode pairs to noninvasively measure hematocrit, the art does not teach specific configurations of apparatus that are used in the noninvasive measurement of hematocrit.
The present invention includes apparatus configured for use in the noninvasive measurement of the hematocrit of a patient. Apparatus incorporating teachings of the present invention include two or more pairs of electrodes. A pressurization component may also be associated with the apparatus of the present invention.
A first embodiment of electrodes incorporating teachings of the present invention includes four individual electrodes that are paired in inner and outer sets. The electrodes may be substantially L-shaped. A first member of each electrode is configured to contact and to be at least partially wrapped around a body part at which hematocrit is to be noninvasively measured. A second member of each electrode is configured to communicate with external electrical componentry that will either apply a voltage to the body part or measure impedance at the body part, as will be described hereinafter in greater detail. In a variation of the first embodiment, one or more of the electrodes may be substantially linear, with a first end thereof configured to be at least partially wrapped around a body part and a second end thereof configured to be connected to external electronic componentry.
A second embodiment of electrodes useful in apparatus of the present invention has two elements, each including a pliable substrate and two electrodes, an electrode of an outer set and an electrode of an inner set. The pliable substrate preferably conforms to the shape of the body part at which hematocrit is to be noninvasively measured and may include a substantially planar member or be configured to at least partially receive the body part (e.g., an open- or close-ended tube configured to at least partially receive a finger). Again, the electrodes may be substantially L-shaped and include a first member and a second member. At least a portion of the first member of each electrode is secured to and carried by the pliable substrate. Thus, as the first members of each of the L-shaped electrodes are brought into contact with a body part at which hematocrit is to be noninvasively measured and the pliable substrate of each of the two elements is at least partially wrapped around the body part, the first member of each electrode is also at least partially wrapped around the body part. In a variation of the second embodiment, one or more of the electrodes may be substantially linear, with a first end thereof configured to be at least partially wrapped around a body part and a second end thereof configured to be connected to external electronic componentry.
A third embodiment of electrodes includes a single, pliable substrate that at least partially carries four electrodes arranged relative to the substrate in inner and outer sets. The pliable substrate preferably conforms to the shape of the body part at which hematocrit is to be noninvasively measured and may include a substantially planar member or be configured to at least partially receive the body part (e.g., as an open-ended or close-ended tube configured to at least partially receive a finger). The electrodes may be L-shaped, as described previously herein with respect to the first and second electrode embodiments, or substantially linear, and are configured to communicate with external electronic componentry.
Apparatus incorporating teachings of the present invention also include a pressurization component configured to apply a predetermined amount of pressure to the body part at which hematocrit is to be noninvasively measured.
A first embodiment of the pressurization component includes a pliable bladder configured to be at least partially wrapped around the body part, over the inner and outer pairs of electrodes, so as to apply increased pressure to the body part as pressure within the bladder is increased (e.g., with air or another fluid).
In a second embodiment, a pliable substrate upon which portions of the electrodes are carried, as in the second and third electrode embodiments described previously herein, comprises a pliable bladder. Accordingly, at least a portion of at least one electrode of each of the inner and outer electrode pairs may be secured to or otherwise carried by the pliable bladder. Prior to introducing pressure into the pliable bladder, the bladder may be substantially planar or configured to at least partially receive the body part at which hematocrit is to be noninvasively measured (e.g., as an open-ended or close-ended tube configured to at least partially receive a finger).
These pliable bladder embodiments of the pressurization component are configured to be connected to a source of pressure. As the pliable bladder is pressurized (e.g., by air pressure or pressure of another fluid), pressure is applied to at least a portion of the body part.
In addition, these pliable bladders may line a receptacle formed in a rigid member and configured to at least partially receive the body part.
In a third embodiment of pressurization component incorporating teachings of the present invention, inner and outer pairs of electrodes, such as those of the first, second, and third electrode embodiments described previously herein, are placed in contact with and at least partially wrapped around a body part at which hematocrit will be measured. The body part is at least partially inserted into a pressure chamber, which is in fluid communication with a source of positive pressure. Portions of one or both electrodes of the inner and outer pairs of electrodes in contact with the body part may also be inserted into the pressure chamber. As the body part is positioned within the pressure chamber, an at least partial seal is formed around the body part. Accordingly, as a positive pressure forms within the pressure chamber, pressure will be applied to the body part.
A system for noninvasively measuring the hematocrit of blood perfusing a living body part (e.g., a finger) in accordance with teachings of the present invention includes a non-invasive hematocrit measurement apparatus and external electronic componentry associated therewith. The electronic componentry of the system includes circuitry that drives first and second alternating currents of different frequencies (e.g., 100 KHz and 10 MHz) between separate points on the body part. The alternating currents may be applied to the body part through input electrodes attached to the body part at the separate points. Also, additional circuitry monitors first and second signals (e.g., voltage waveforms) induced in the body part by the first and second currents (e.g., by monitoring output electrodes attached to the body part), and other circuitry generates first and second pulsatile signals and first and second baseline signals from the first and second induced signals. Determining circuitry then calculates the hematocrit of the blood from the first and second pulsatile signals and the first and second baseline signals. This calculation may be performed, for example, by determining the hematocrit (H) from the following equation:
[(1+(fxe2x88x921)H)/(1xe2x88x92H)]{1+[((af(exe2x88x92bxxe2x88x92c))x/(1xe2x88x92x))xe2x88x921]H}/{1+[((af(exe2x88x92bxxe2x88x92c))/(1xe2x88x92x))xe2x88x921]H}=Cxc2x7(xcex94VoltH/VH2)/(xcex94VoltL/VoltL2),
where (f, a, b, x, c, and C) are various constants, as will be described below, xcex94VoltH and xcex94VoltL are the first and second pulsatile signals, and VH and VL are the first and second baseline signals.
In accordance with another embodiment of the system of the present invention, a system for measuring the hematocrit of blood perfusing a living body part includes electrodes positioned on the surface of the body part. A measuring device measures the electrical impedance at one or more frequencies between the electrodes. Also, a chamber is positioned to surround the body part between the electrodes, and a measuring apparatus measures pulsatile blood volume by the pulsatile-related change in internal pressure within the chamber. Further, a calculating device (e.g., a programmed microprocessor) determines the blood hematocrit from the measurements of impedance and pulsatile blood volume. The device may determine the hematocrit H in accordance with the following equations:
H=(xcfx81xe2x88x9258)/(0.01 xcfx81+0.435), and
xcfx81=xcex94VZ02/L2xcex94Z,
where xcex94V is the change in pulsatile blood volume at any point in time, xcex94Z is the change of impedance at the same point in time, L is a constant which will be described below, and Z0 is the baseline impedance at the beginning of each pulse.
In a further embodiment, the system for determining blood hematocrit includes circuitry that produces a current signal including a first, relatively low frequency portion and a second, relatively high frequency portion, and the hematocrit measuring apparatus, which stimulates a living body part containing blood with the current signal. Also, additional circuitry of the hematocrit measuring apparatus is used to sense voltages at the first and second frequencies induced in the body part by the stimulation thereof, and further circuitry detects signal envelopes of the sensed voltages, with each signal envelope having a pulsatile component and a baseline component. Isolation circuitry isolates the pulsatile components and baseline components of the detected signal envelopes, and extraction circuitry extracts one or more sets of time-matched segments of the isolated pulsatile components and one or more sets of time-matched segments of the isolated baseline components. Further, other circuitry effectively correlates the blood hematocrit to the product of the ratio of the time-matched segments of the pulsatile components and the inverse ratio of the squares of the time-matched segments of the baseline components.
Another embodiment of the system includes an apparatus for determining the hematocrit of blood perfusing a living body part from relatively low frequency pulsatile and baseline signals induced in the body part, and from relatively high frequency pulsatile and baseline signals also induced in the body part, includes circuitry that effectively determines the ratio of the product of the relatively high frequency pulsatile signal and the square of the relatively low frequency baseline signal to the product of the relatively low frequency pulsatile signal and the square of the relatively high frequency baseline signal. The apparatus also includes circuitry that correlates the blood hematocrit to the effectively determined ratio.
Other embodiments of the invention include methods of measuring the hematocrit of blood perfusing a living body part, and a method of determining blood hematocrit, that generally correspond to the systems and apparatus described above.
Other features and advantages of the present invention will become apparent to those of skill in the art through a consideration of the ensuing description, the accompanying drawings, and the appended claims.

System and method for in-vivo hematocrit measurement using impedance and pressure plethysmography


Distributed feedback mirror cavities are found capable of sufficient reflectance-loss characteristics to permit lasing in two or a single quantum well structure in which lasing is in the thin (quantum) dimension. Such lasers sometimes known as "quantum well surface emitting lasers" are of sufficiently low threshold value as to permit use in integrated circuits of high integration density--e.g. at 1 micron design rules. Anticipated uses, now made possible, include optical circuitry for computer chip interconnect as well as optoelectric integrated circuits for many purposes including computing itself.

No technology has had as profound an influence as the integrated circuit. Most of the wonders of our society would be impossible without it. A single example, the modern computer, plays a role that affects the wellbeing of people in every walk of life and in every country.
It has been confidently predicted for many years that future generation integrated circuits would include or even take the fundamental form of integrated photonic rather than electronic devices. While many uses may involve optical pumping, most significant impact is expected to depend upon electrical pumping. From this standpoint, that is from the standpoint of laser operation, per se, and also from the standpoint of functions to be performed, most valuable implementation will take the form of the Opto Electronic Integrated Circuit. Included electronics--generally semiconductor electronics--will serve to operate lasers as well as to interact between photonics and electronics generally.
Contemplated uses for integrated lasers--largely represented by OEIC's--include integration with the driving electronics itself as well as inclusion of elements to provide for interaction both within photonic parts of the circuit and between photonic and electronic parts. Examples of purely photonic interaction include laser-to-detector. There are many examples of the second category.
While overcoming limitations of present day electronic computers will, by all estimates, lead to assignment of at least some computer functions to lasers, intermediate development is expected to take the form of optical interconnection to overcome present limits interposed by hard wiring. Realization of optical interconnect, chip-to-chip as well as within chip, will be dependent upon a high degree of integration consistent with low cost.
Other uses for OEIC's as identified in recent literature include imaging, image processing and optical gas detection.
Full implementation of the integrated laser, e.g. of the OEIC, will take advantage of very profound emerging processing advances. Demonstrated techniques have, for example, depended on close lattice matching, but have also taken advantage of defect minimization afforded through growth of extremely thin layers in non-lattice matched epitaxy as well. Such considerations have been quite valuable in conjunction with evolving Quantum Well structures with their well appreciated performance advantages (low threshold, narrow bandwidth, high brightness, high effiency). See Y. Arakawa and A. Yariv, IEEE J. Quantum Electron. QE-21, 1666 (1985). Remarkable developments confirm the likelihood of commercial abricattion of discrete QW laser structures in the near future. Dislocation densities have been reduced. Useful Distributed Feed Back mirrors have been built without need for cleavage (by Molecular Beam Epitaxy as well as by Metal Organic Chemical Vapor Deposition.
It is confidently expected that most valuable use will entail a high level of integration. The most significant obstacle to laser integration is power dissipation. The present level of silicon Large Scale Integration is attributable to the very low power requirements for operation. In the limit, power dissipation, some finite fraction of power input, limits the number of devices that may be integrated on a chip, or, in more general terms, the fraction of wafer area devoted to active use. Now available silicon LSI "megachips", soon to yield to still greater miniaturization and integration density, are critically dependent on this consideration. By the same token, relative lack of progress in laser integration must be ascribed to the relatively high required threshold power levels.
Extensive literature clearly shows that workers, worldwide look to QW laser structures as promising from the standpoint of threshold power. Much of the reported work until recently has dealt with edge-emitting structures in which the initially emitted beam is parallel to the major substrate surface. Such structures, while very significant, are not regarded as offering the lower threshold power levels needed for desired integration density.
Very promising recent results involve Quantum Well Vertical Cavity Lasers. As the terminology implies, the emitted beam is now initially non-parallel --generally normal--to the major substrate surface, or more generally, non-parallel to the major dimensions of the quantum well (parallel to the critical quantum well dimension). Representative work is described by Gourley et al in Applied Physics Letters, 49 (9), p. 489 (1 Sept. 1986). In this work conducted at Sandia National Laboratories, the authors describe a passive structure (no non-linear active material) consisting of a cavity of GaAs bounded by DFB mirrors of alternating layers of GaAs and AlAs. The quarter-wave mirror structures in the described experiment consisted of eight layers each of the two materials. Excellent properties observed showed a 54 .ANG. centered transmission band at a wavelength of 0.956 nm. The authors report certain properties from which it is possible to calculate absorption/scattering losses of their structure. Properties reported include a peak transmittance of 45%, as well as their calculated "ideal structure" transmittance of 68%.
Much of the work concerning QWVCL's has involved direct use of the initially vertically directed emitted beam. This is of value, for example, in chip-to-chip communication and in certain other instances in which laser output is to be coupled with external circuitry. The vertical structure, however, also offers low threshold-related advantages for use involving communication within the chip (or under other circumstances in which coupling is in a direction parallel to the major substrate plane). For such purposes, the initially non-parallel beam as emitted by the laser may be redirected, for example, by use of a mirror or prism external to the cavity itself. Such mirrors, likely DFB's, of the same nature discussed in conjunction with the cavity itself could be fabricated as part of an integrated circuit. In passing, it may be noted that while "surface emitting" structures are generally though of in terms of true vertical cavities, there is no reason why they cannot be at some other angle to facilitate desired operation, emitting at 90.degree. or any other out-of-plane angle, or even emitting in-plane. It is implicit, as well, that "surface emitting" may not mean free surface emitting. "Surface emitting" has reference only to the surface of the concerned mirror defining the laser cavity. This "surface" may, in fact, be an interface with some other material/element, e.g., may relate to the interface with a prism or other element designed to direct the beam. (Use of the term, Quantum Well Vertical Cavity Laser, is designed to avoid some of these implied, but unintended limitations).
The Gourley et al article is representative of the most advanced state of the art at least in terms of DFB mirror cavities. It serves as basis for explaining the general view that a small number of quantum wells is inadequate for lasing. A Fabray-Perot etalon has a net maximal transmission of T.sup.2 /(T+A).sup.2, a relationship well-known to workers in relevant fields and found in many textbooks on optics. T is the transmittance of a single mirror of the Fabray-Perot etalon and A is the fraction of energy absorbed by the same mirror. Energy not transmitted or absorbed is reflected. For quarter wavelength interference mirrors in their 8 layer pair GaAs-AlAs mirror structure, one obtains reflectivity very close to 93.6% and a transmittance of 5.2% per mirror. Subtracting the sum of 93.6% +5.2%=98.8% from 100% yields a loss of 1.2% per single pass. Lasing requires a gain of greater than 1.2% in the active structure to offset this loss. Gains offered by quantum well structures are significantly less than 1.2%. For example, the authors of "Ultimate Limit in Low Threshold Quantum Well GaAlAs Semiconductor Lasers", Applied Physics Letters, Vol. 52, pp. 88-90, 11 Jan. 1988, reported experimental results which indicate a maximum achievable gain of 0.3% for a SQW based on quantum wells made of GaAs a well-studied representative member of the promising class of compound semiconductors.
For the author's mirror structure, reflectance values needed for lasing for a small number of quantum wells (four or fewer), twenty or more mirror pairs are required for needed reflectance. Based on the very conservative estimate that the 1.2% loss for the eight pair cavity is not increased at all for the required number of pairs, still results in the conclusion that lasing threshold has not been reached. Stated differently, the results of this reported work lead directly to the conclusion that a minimum of four quantum wells is necessary to offset loss and thereby achieve lasing in the best available materials.
It is the general view that lasing materials within the compound semiconductor families (III-V's, II-VI's and usual ternary, quaternary and higher order materials) have similar maximum gains, i.e. within the range 0.2%-0.4%. All numbers are for single quantum well structures with effective gain for multiple structures increasing linearly as the number of wells increases (2.times.0.2%=0.4% to 4.times.0.2%=0.8% or 0.4%-0.8% for a duplex structure). In addition, cavity efficiency is dependent upon mirror efficiency which, in turn, varies .about.as the reciprocal of the difference in refractive index between the two successive layered mirror materials (.DELTA. n). Since, in general, refractive index for suitable mirror materials varies less for increasing wavelength, .DELTA. n values are typically less so that a greater number of layers is generally required for the necessary cumulative reflectivities.
The work reported above represents the worldwide view that attainable vertical cavity structures (QWVCL's) require a threshold level of at least 3,000 amperes/square centimeter (3mA/100 .mu.m.sup.2) in order to offset unavoidable losses in the cavity. The primary implication of this conclusion is relevant to minimum required power dissipation and, therefore, to maximum integration density. This understanding is equivalent to the accepted view that lasing in QW structures is not attainable for structures containing fewer than a minimum of four quantum wells. Whereas requirements vary at different wavelengths and in accordance with other factors (e.g. available .DELTA. n's), the general view is that such considerations are not at variance--in fact often suggest still greater numbers of wells.
Much of the above is concerned primarily with light pumping. Accordingly, conclusions in the literature relative to required gain, numbers of quantum wells, etc. are largely derived from reported work on light pumping. As indicated, anticipated value, while not ignoring light pumping, is primarily in electrical pumping. All of the reported work is relevant to electrical pumping. On the other hand, it is well known that achievements in optical pumping have not been duplicated in the electrical analog. For example, whereas there is a body of reported work on optically pumped devices operating cw at room temperature, reported electrically pumped devices, have, in the main, been pulsed, or if cw, have been cooled.


An equalization device (500) includes a sample hold unit (501) that samples and holds an input signal, a multiplication unit (503) that multiplies the output signal of the sample hold unit (501) by a coefficient, a sample hold unit (502) that samples and holds the input signal at a timing delayed from the sample hold timing of the sample hold unit (501) by one symbol length, a multiplication unit (504) that multiplies the output signal of the sample hold unit (502) by a coefficient, and an addition unit (505) that adds the output signal of the multiplication unit (503) and the output signal of the multiplication unit (504) to output a sum signal.

In recent years, the shortage of transmission line bands is coming to the surface along with the increase in the transmission speed. A problem caused by the shortage of transmission line bands is intersymbol interference. The intersymbol interference is the interference between adjacent signals each representing a bit value "0" or "1". Since the waveform of a signal degrades due to the intersymbol interference, it is difficult to determine the bit value from the input signal on the receiver side.
A method for solving the degradation in the waveform of the input signal is waveform equalization. Waveform equalization is a technique of intentionally changing part of a signal waveform in accordance with degradation in the signal waveform caused by intersymbol interference.
One of the waveform equalization techniques is decision-feedback equalization that performs processing only on the receiver side. The decision-feedback equalization is disclosed in, for example, non-patent literature 1. In the decision-feedback equalization, a bit value represented by an input signal is determined from the waveform of the input signal. Based on the determination result, the influence of degradation in the waveform of the already received input signal is removed from the next signal input to the receiver.
FIG. 15 shows an example of an input signal degraded by intersymbol interference. Referring to FIG. 15, C0 represents a main tap that is a bit to be determined; C−1, a precursor that is the waveform distortion of the bit immediately before the main tap C0; C1, a first post-cursor that is the waveform distortion of the bit immediately after the main tap C0; C2, a second post-cursor; and C3, a third post-cursor. In the decision-feedback equalization, the intersymbol interference from the first post-cursor C1 can be removed.
In the decision-feedback equalization, the determination result is fed back. Hence, feedback to the bit next to the determined bit, that is, the first post-cursor is the fastest. The transmission rate is rate-limited by the delay time of the feedback. To avoid the rate-limitation of the transmission rate, speculative decision-feedback equalization has been proposed. The speculative decision-feedback equalization is disclosed in, for example, non-patent literature 2. In the speculative decision-feedback equalization, equalization is executed in advance for both preceding bits having values "0" and "1". After determination of the bit value, the correct execution result is selected and output. For this reason, the fastest feedback to the first post-cursor is unnecessary. This allows to increase the time constraint of feedback and achieve a higher transmission rate.

Equalization device, equalization method, and recording medium


A column circuit for an image sensor includes a first column read circuit configured to read data of a first column line, and a second column read circuit configured to read data of a second column line, wherein, during a binning mode, data from two or more pixels are outputted through the first column line and stored in the first column read circuit in a first phase, data from two or more pixels are outputted through the second column line and stored in the second column read circuit in a second phase, and charges are shared between the first column read circuit and the second column read circuit in a third phase.

Exemplary embodiments of the present invention relate to a technology for binning a plurality of pixel data.
Demands for digital cameras are explosively increasing along with the advancement of video communication through the Internet. Also, as mobile communication terminals, such as Person Digital Assistants (PDAs) and Code Division Multiple Access (COMA) terminals, equipped with cameras become popular, the demands for small-sized camera modules are increasing as well.
A camera module basically includes an image sensor. An image sensor generally refers to a device for transforming an optical image into electrical signals. As for the image sensor, a Charge Coupled Device (CCD) and a complementary metal-oxide semiconductor (CMOS) image sensor are widely used.
The CCD is complicated in its driving method, consumes much power, and has a complex fabrication process due to many masking processes. Moreover, since a signal processing circuit cannot be realized within a single chip, it may be difficult to embody the CCD as one chip. On the contrary, a CMOS image sensor can have monolithic integration of control, driving, and signal processing circuits in a single chip. Moreover, it may be more economical to use the CMOS image sensor than to use the conventional CCD, because the CMOS image sensor may operate at a lower power level, consume a smaller amount of power, and be compatible with more peripheral devices in comparison to the CCD and there is a useful standard CMOS fabrication process established.
The number of pixels of an image sensor increases, as technology progresses. In other words, the definition/resolution of an image sensor increases. The increased definition leads to an increase in the amount of data to be processed. Therefore, a technology of binning data of a plurality of pixels into/as one data is being used. According to the conventional pixel binning technology, binning is performed on a pixel array. In this case, however, binning is limited to using a certain pixel structure.

Column circuit and pixel binning circuit for image sensor


An ultrasound imaging console includes receive circuitry that receives a set of echoes produced in response to an ultrasound signal traversing blood flowing in a portion of a vessel in a field of view, a beamformer that beamforms the echoes, a velocity processor that determines flow direction and magnitude of the flowing blood based on the beamformed echoes, and a rendering engine that displays the determined flow direction and magnitude.

Ultrasound imaging provides information about the interior of a subject. For example, ultrasound imaging can be used to generate an image of a blood vessel and estimate blood flow velocity inside the blood vessel.
With conventional blood flow velocity estimation, a pulse-echo field oscillates in the axial direction along the axis of the ultrasound beam. This is illustrated in FIG. 1 in which a transducer array 100 produces an ultrasound beam 102 that propagates in the axial direction along the z-axis (or depth) 104. Blood scatterers passing through the field of interest produce a signal with a frequency component proportional to the axial velocity, and the axial velocity component (VZ) 106 can be estimated.
The transverse oscillation (TO) blood velocity estimation approach has been used to estimate both VZ 106 and the transverse velocity component (VX) 108, along the transverse axis 110, of the velocity vector 112. With the transverse oscillation approach, a transverse oscillation is introduced in the ultrasound field, and this oscillation generates signals that depend on the transverse oscillation. The basic idea is to create a double-oscillating pulse-echo field using a one dimensional (1D) transducer array.
Color flow mapping (CFM) is one approach to visually show velocity. An example of this is shown in FIG. 2, in which first flow 202 through a first vessel 204 and second flow 206 through a second vessel 208 towards the transducer is displayed using a first color (red shades), and third flow 210 through the first vessel 204 and fourth flow 212 through the second vessel 208 away from the transducer is displayed using a second different color (blue shades). Intensity is proportional to the velocity of the flow.
Unfortunately, with color flow mapping, the two colors only show relative flow with respect to the ultrasound transducer. Furthermore, with color flow mapping, blood flow perpendicular to the ultrasound beam cannot be seen. Moreover, with color flow mapping, the colors do not indicate the direction and magnitude of the blood flow. In view of at least the above, there is an unresolved need for other approaches for visualizing blood flow.


A Wireless Fidelity (WI-FI) connection method and a mobile terminal for efficiently connecting to hidden access points. X parameters of a target Access Point (AP) are acquired, the X parameters at least includes the target SSID of the target AP, where X is a positive integer. WI-FI scanning is performed according to the X parameters. When the target AP is not found by the scanning, encryption schemes of one or more hidden APs are acquired to get the H encryption schemes, where H is a positive integer. WI-FI scanning is performed according to the target SSID and at least one of the H encryption schemes.

Along with rapid development of the information technology, use of mobile terminals (such as mobile phone and tablet computer) becomes increasingly popular. Users have higher requirements on the mobile terminals. They not only require the mobile terminal to have a relatively high processing speed, but also increasingly rely upon WI-FI connection. Along with popularization of the mobile terminals and the WI-FI, the event of accessing a WI-FI network through a mobile terminal occurs more and more frequently.

WI-FI connection method, mobile terminal and storage medium

GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD.


A human-machine interaction somatosensory vehicle is provided. The human-machine interaction somatosensory vehicle may include a vehicle body and two wheels mounted on the vehicle body. The two wheels may rotate around the vehicle body in a radial direction. The vehicle body may include a support frame, two pedal devices mounted on the support frame, a controller, and a driving device configured to drive the two wheels. The support frame may be an integral structure rotatably connected to the two pedal devices. The two pedal devices each may include a pedal foot board and a first position sensor. The first position sensor may be mounted between the pedal foot board and the support frame, and configured to detect stress information of the pedal device. The controller may be configured to control the driving device to drive the two wheels to move or turn based on the stress information of the pedal devices.

Recent years have seen the development of a variety of personal transportation vehicles. Human-machine interaction vehicles, also called human-machine interaction somatosensory vehicles, generally fall into two categories: with a handle bar (or a steering pole) and without a handle bar. A human-machine interaction vehicle without a handle bar, also known as a self-balancing scooter, a hoverboard, etc., can be steered by shifts in a user's positions. For example, the user may lean forward or backward to control the speed of the human-machine interaction vehicle. The self-balancing scooter often consists of two motorized wheels connected to a pair of articulated pads on which the user places his/her feet. The pads are rotatable and the user can control the human-machine interaction vehicle to make a turn by twisting the pads with his/her feet. Such a structure is relatively complicated and brings certain difficulties in the maintenance and repair of the human-machine interaction vehicle. In addition, the human-machine interaction vehicle can recognize shifts in the user's position and steer the vehicle in accordance with the user's intentions based on data relating to the shifts in the user's position. This requires the user to place two feet on the pads and the user may not be able to effectively manipulate the human-machine interaction vehicle when sitting or standing on one foot. In other designs, the human-machine interaction vehicle may use pressure sensors to calculate a center of gravity of the user and identify shifts of the center of gravity, but data from these pressure sensors may be skewed if the user is, for example, carrying bags. Therefore, it is desirable to provide human-machine interaction vehicles with relatively simple structures and more efficient methods for controlling the human-machine interaction vehicles.

HANGZHOU CHIC INTELLIGENT TECHNOLOGY CO., LTD.


The invention relates to a controller, and more particularly, to systems, devices and methods of controlling a sensor having a resonating mass. The controller includes: an analog-to-digital converter (ADC) unit for extracting a digitized sensor signal from the sensor signal; a phase controller for generating, based on the digitized sensor signal, a phase-controlled signal that is locked in phase with the digitized sensor signal; an amplitude controller for applying a gain to the digitized sensor signal to thereby generate an amplitude-adjusted signal; a modulator for modulating the amplitude-adjusted signal to thereby generate a modulated signal; and a phase shifter for shifting the phase of the modulated signal by 90 degrees. The output signal from the phase shifter is amplified and input to the drive for exciting the resonating mass, to thereby form a closed resonance loop for controlling the oscillation amplitude of the resonating mass.

A. Technical Field
The present invention relates to a sensor controller, and more particularly, to a controller having a closed loop to control the oscillation amplitude of a resonating mass in a sensor.
B. Background of the Invention
A rate of rotation sensor has been widely applied to measure the angular velocity of a moving object. FIG. 1 shows a schematic diagram 100 of a conventional gyroscope for measuring the rate of rotation of a sensor. As depicted, the conventional gyroscope includes: a sensor signal processor 114 for processing a sensor signal 106 from the sensor of a sensor unit 102; and a driver signal processor 112 for generating and providing a driver signal (or, equivalently, forcing signal or excitation signal) 108 to a driver of the sensor unit 102.
Such a conventional system has several problems. First, the excitation frequency, which is derived from the system clock, may not be close to the resonant frequency under certain circumstances, such as the start-up stage or transient stages caused by an external shock event. An error of a few percent in the system clock frequency, which is typically an integer multiple of the resonant frequency in the steady state only, from its target frequency can generate a very long start-up time or even make it impossible to start the sensor movement. As a consequence, the conventional system requires a factory calibration of the voltage-controlled oscillator (VCO) of the system clock.
Second, a conventional system is implemented mostly in analog domain, i.e., it uses more analog components than digital components. Since a large portion of the processes in the controller are based on analog functions, the conventional controller has low immunity to process spread, while it typically has a high form factor and a high power consumption rate.
Therefore, a better solution is needed to address the main issues, including long start-up time, low immunity to process spread, poor protection against external shock events, large form factor, and low efficiency in power consumption, of the conventional sensor controller.


A method for preparing a compound and a method for preparing a polymer employing the same are provided. The method for preparing a compound includes reacting a compound having a structure represented by Formula (I) with a compound having a structure represented by Formula (III) in the presence of a compound having a structure represented by Formula (II) to obtain a compound having a structure represented by Formula (IV)

Polyarylene sulfide (PAS) (or polythioether sulfone (PTES)) is a material with good physical characteristics such as thermal resistance, chemical resistance, flame resistance, non-toxicity, and electrical insulation characteristics. Thus, polyarylene sulfide (PAS) (or polythioether sulfone (PTES)) can be used in computer accessories and auto accessories; as a coating for parts that come into contact with corrosive chemicals; and as industrial fibers having chemical resistance.
However, conventional methods for preparing polyarylene sulfide (PAS), polythioether sulfone (PTES), or monomers thereof are halogen-containing processes that, in principle, results in a low yield and produces unrecyclable halogen-containing byproducts that can cause environmental pollution.

Method for preparing compound and method for preparing polymer employing the same

Abstract: wherein Ar1 is substituted or unsubstituted aryl group; X is —O—, —S—, or —NH—; R1 is independently hydrogen or C1-6 alkyl group; R2 is hydroxyl group, C1-6 alkyl group, phenyl group, or tolyl group; and R3 is independently C1-6 alkyl group, C5-8 cycloalkyl group, or C2-6 alkoxyalkyl group.


A system for endoscopic surgery within a body lumen of a patient including a flexible catheter having an expandable balloon at a distal portion and an access opening. The expandable balloon is expandable from a collapsed insertion configuration to an expanded configuration to provide an expanded chamber on a first side of the catheter. The access opening provides a window to access target tissue. The catheter includes a lumen dimensioned to receive an endoscopic instrument therethrough such that a distal end of the endoscopic instrument is positionable within the expanded chamber and angled laterally within the expanded chamber to access the target tissue through the window.

This application relates to minimally invasive devices for operatively treating tissue and more specifically to minimally invasive devices which expand and/or reshape the body lumen to increase and/or optimize the working space to enable or enhance maneuverability of endoscopic instruments.
Endoscopic procedures involving the gastrointestinal system offer advantages over conventional surgery in that they are typically less invasive and may provide or improve visualization.
It may be advantageous to provide a stable, optimal working (operating) space to expand and/or reconfigure (reshape) the working space during a minimally invasive (endoscopic) procedure. Such stable, expanded and/or optimally configured working space facilitates independent manipulation of the instruments and endoscope and improves endoscopic visualization of the target tissues.
It may also be advantageous to provide endoscopic technology for organizing the endoscope, instruments, and working space in a manner that can maximize the working space for treatment. The larger working space can improve the ability to manipulate the instruments and endoscope in a minimally-invasive manner from outside the body. It is advantageous to have a working space that has tips of the instruments as far as practical from the target tissue to improve the maneuverability of the instruments and provide additional flexibility in approaching and visualizing the target tissue, perhaps providing more operating room for selecting a trajectory of the instruments toward the target tissue that is, for example, at least substantially perpendicular or substantially parallel to the plane of dissection of the target tissue.

System for a minimally-invasive treatment within a body lumen


A through the hole rotary position sensor which incorporates a single ring magnet with a central aperture is disclosed. The rotating shaft whose angular position is to be sensed is adapted to be received in the central aperture. The through the hole rotary position sensor in accordance with the present invention also includes a pair of pole pieces which extend at least partially around the circular magnet. One or more magnetic flux responsive elements are disposed adjacent the pole pieces. In order to shield the sensor from undesirable magnetic flux influences through the rotatable shaft, an optional internal shunt ring may be provided around the exterior of the rotatable shaft. In order to shield the sensor from undesirable external magnetic flux influences, an optional external shunt ring and top and bottom shunt discs may also be provided. The circular magnet, pole pieces, magnetic flux responsive element, optional shunt rings and shunt discs are carried by a non-magnetic housing. By utilizing a simple circular or ring magnet, the cost and complexity of the sensor is relatively lower relative to other known sensors.

1. Field of the Invention
The present invention relates to a rotary position sensor and more particularly to a through the hole rotary position sensor.
2. Description of the Prior Art
Devices are known for providing a signal representative of the angular position of a rotatable device. In particular, potentiometers with moveable wiper contacts were known to be used to provide an electrical signal representative of the angular position of a rotatable member. Although such potentiometers provided satisfactory results, such potentiometers were subject to wear which increased the need and frequency of replacement of such devices, thus increasing warranty costs in automobile and commercial applications.
In order to solve this problem, non-contacting sensors have been developed to provide a signal representative of the angular position of a rotatable device. Such sensors, often referred to as rotary position sensors, are known to be used in many applications including applications in the automotive industry. These rotary position sensors are non-contacting and provide an electrical signal representative of the angular position of a rotatable member, such as various automotive applications as described below.
Such rotary position sensors normally include a circular magnet rigidly attached to a rotatable device whose angular position is to be measured. A magnetic flux responsive element sensitive to magnetic flux in one plane is typically disposed and mounted stationary relative to the magnet to receive components of the magnetic flux as the magnet and rotatable device are rotated. One or more pole pieces are also typically provided. In operation, as the combination of the rotatable device and magnet are rotated, components of magnetic flux are sensed by the magnetic flux responsive element causing the output of the magnetic flux responsive element to vary as a function of the angular position of the rotatable device.
Various magnetic flux responsive elements are known to be used in such applications. Probably the most popular is a Hall effect device which provides an electrical voltage signal as a function of the magnetic flux received in a particular plane. Magnetoresistive elements (MRE), for example, permalloy, are also known. Such magnetoresistive elements (MRE) provide an electrical resistance signal proportional to the magnetic flux in a particular direction. Thus, as the magnet rotates, components of magnetic flux in one plane will vary, causing the output signal from the Hall effect device or the MRE to vary to provide a signal representative of the angular position of the rotatable device.
Two types of rotary position sensors are known; end cap and so called through the hole rotary position sensors. The particular type of rotary position used is determined by the application.
Such end cap rotary position sensors are configured to be disposed and mechanically linked to the end of a rotatable shaft whose angular position is to be sensed. Examples of such rotary position sensors used in end cap applications are disclosed in commonly owned U.S. Pat. Nos. 5,497,081 and 5,818,223, hereby incorporated by reference. In general, rotary position sensors used in end cap applications normally include a circular magnet with a central aperture, a magnetic flux responsive element and one or more pole pieces. Normally the magnetic flux responsive element is disposed adjacent the pole pieces and centrally disposed within the central aperture of the circular magnet.
As mentioned above, through the hole rotary position sensors are also known. Such through the hole rotary position sensors also include a circular magnet with a central aperture. However, in through the hole applications, the shaft of the rotatable device, whose angular position is to be sensed, is received in the central aperture of the magnet. As such, when the rotatable shaft is rotated, the magnet rotates therewith. Such through the hole rotary position sensors also include a magnetic flux responsive element and one or more pole pieces disposed adjacent the outer diameter of the circular magnet.
Various through the hole rotary position sensors are known in the art. For example, through the hole rotary position sensors are disclosed, for example, in U.S. Pat. Nos. 5,444,369; 5,742,160; 6,124,710; 6,188,216; and 6,275,025. Such through the hole sensors often include custom magnets, while other sensors require more than one magnet resulting in relatively complicated and expensive sensors. For example, the '216 patent discloses a sensor that requires two magnets, while the '710 patent requires a disc-shaped magnet. Similarly, the '025 and '369 patent also require irregular shaped magnets which can add to the cost and complexity of the sensor. Thus, there is a need for a through the hole rotary position sensor that can be formed with a relatively standard ring magnet to reduce the cost and complexity of the overall device.

Through the hole rotary position sensor with a pair of pole pieces disposed around the periphery of the circular magnet