An adaptive modulation scheme relating to an RA problem for maximizing the transmission rates of all users for maximum transmission rates in an OFDMA system including some users requiring to use services at fixed data rates. The scheme proposes introduction of an adaptive modulation using linear programming into an existing scheme for a system including a single kind of users, thereby enabling simultaneous execution of the adaptive modulation for all users in a system including two kinds of users. Further, the invention proposes another scheme of sequentially allocating subchannels to the users when the fixed transmission rate has a sufficiently small value, in order to reduce the complexity.

1. Field of the Invention
The present invention relates generally to a modulation/demodulation scheme in an Orthogonal Frequency Division Multiple Access (OFDMA) mobile communication system, and more particularly to a method for allocating subchannels in order to apply an optimum modulation/demodulation scheme according to channel conditions.
2. Description of the Related Art
Currently, mobile communication systems are being developed to provide high speed and high quality mobile communication services, such as data services and multimedia services beyond the initial voice-centered services. Further, the 3rd generation (3G) mobile communication systems, which is commonly classified into asynchronous mobile communication systems (3GPP) and synchronous mobile communication systems (3GPP2), are being standardized for high speed and high quality wireless data packet services. For example, the 3GPP is now preparing standardizations for the High Speed Downlink Packet Access (HSDPA) scheme and the 3GPP2 is now preparing standardizations for the 1× Evolved Data and Voice (1× EV-DV) scheme. Moreover, the 4th generation (4G) mobile communication systems are intended to provide higher speed and higher quality multimedia service than the 3G mobile communication systems.
However, due to the wireless channel conditions, various factors may disturb employment of high degree modulations and high coding rates, which are necessary to provide a high speed and high quality data service. Such factors include white noise, reception signal power changes due to fading, shadowing, Doppler effect due to movement and frequent velocity change of a terminal, interference by another user and multipath signals, etc. Therefore, it is necessary to use a proper modulation scheme and coding scheme in consideration of the changing wireless channel conditions.
In order to provide such a high speed and high quality data service, further advanced technology having an enhanced adaptability for the changing channel conditions as well as the conventional technologies provided by the existing mobile communication systems is necessary.
An Adaptive Modulation and Coding Scheme (AMCS) is a representative of proposals of such advanced technologies. In the AMCS, the modulation scheme and the coding scheme of a data channel are determined according to the channel conditions between a cell and a user, thereby improving the use efficiency of the entire cell. The AMCS classifies the channel conditions into multiple levels and adaptively determines the modulation scheme and the coding scheme according to the levels.
Quadrature Phase Shift Keying (QPSK), 8PSK, and 16QAM (Quadrature Amplitude Modulation) are currently discussed as the possible modulation/demodulation schemes. Additionally, various coding rates, e.g., from ¼ to 1, are considered as the coding rates for the AMCS. Therefore, a mobile communication system using the AMCS applies a high degree modulation/demodulation scheme (8PSK, 16QAM, etc.) and a high coding rate to terminals using high quality channels (e.g., terminals located adjacent to a base station). However, the mobile communication system using the AMCS applies a low degree modulation/demodulation scheme (QPSK) and a low coding rate to terminals using relatively low quality channels (e.g., terminals located at a cell boundary region).
Use of an Orthogonal Frequency Division Multiplexing (OFDM) scheme is highly recommended for the high speed and high quality data service as described above. Therefore, use of the OFDM scheme is now taken into deep consideration for the 4G mobile communication system.
A representative system utilizing the OFDM scheme is an OFDMA-Frequency Division Multiple Access (OFDM-FDMA) system utilizing a multiple access scheme for multiple users, in which all users simultaneously use the entire time while using other subchannels. In an OFDMA system utilizing the AMCS, effective assignment of subchannels to users and determination of modulation schemes for the users should be performed at each time period according to the channel conditions. This method can effectively use all subchannels, except when all users are in deep paging, because the channels between users in the same subchannel are independent from each other. Further, this method can provide a channel diversity effect between users at different locations.
Current research in the AMCS for a system utilizing the OFDMA scheme are being in looked at from two points of view. One standpoint relates to a Margin Adaptive (MA) problem for minimizing the entire transmission power based on given transmission rates of all users and the other standpoint relates to a Rate Adaptive (RA) problem for maximizing the transmission rates of users based on a given entire transmission power.
The RA problem for maximizing a transmission rate can be expressed as shown in Equation (1).
                                                        max                                                c                                      k                    ,                    n                                                  ,                                  ρ                                      k                    ,                    n                                                                                min                k                                                          R                k                                              =                                    max                                                c                                      k                    ,                    n                                                  ,                                  ρ                                      k                    ,                    n                                                                                min                k                                                                            ∑                                      n                    =                    1                                    N                                                                                c                                          k                      ,                      n                                                        ·                                      ρ                                          k                      ,                      n                                                                                subject                                                                                to                                                                                ∑                                              k                        =                        1                                            K                                                                                ∑                                                  n                          =                          1                                                N                                                                                f                            k                                                                                (                                                          c                                                              k                                ,                                n                                                                                )                                                                                ρ                                                          k                              ,                              n                                                                                /                                                      α                                                          k                              ,                              n                                                        2                                                                                ≦                                  P                  T                                                                                ∑                                                  k                          =                          1                                                K                                                                                ρ                                                  k                          ,                          n                                                                                =                    1                                    ,                                      for                                                                                all                                                                                n                                                                                (        1        )
The original problem expressed as Equation 1 can be replaced by Equation (2) as an equivalent expression shown below.
                                          max                                          c                                  k                  ,                  n                                            ,                              ρ                                  k                  ,                  n                                                                        z                                                                                subject                                                                                to                                                                                R                      k                                                        =                                                                                ∑                                                  n                          =                          1                                                N                                                                                c                                                      k                            ,                            n                                                                          ·                                                  ρ                                                      k                            ,                            n                                                                                =                    z                                                  ,                                  for                                                                                all                                                                                k                                                                                ∑                                              k                        =                        1                                            K                                                                                ∑                                                  n                          =                          1                                                N                                                                                f                            k                                                                                (                                                          c                                                              k                                ,                                n                                                                                )                                                                                ρ                                                          k                              ,                              n                                                                                /                                                      α                                                          k                              ,                              n                                                        2                                                                                ≤                                      P                    T                                                                                ∑                                                  k                          =                          1                                                K                                                                                ρ                                                  k                          ,                          n                                                                                =                    1                                    ,                                      for                                                                                all                                                                                n                                                                                (        2        )
In Equations (1) and (2), ρk,n is an identifier (binary variable) indicating that the k-th user occupies the n-th subcarrier, ck,n indicates the k-th user's bit allocated to the n-th subcarrier, Rk indicates k-th user's data rate, PT indicates total power, and ƒk(c) indicates required received power for reliable reception of c bits/symbol.
The AMCS for the system utilizing the OFDMA scheme independently considers the RA problem and the MA problem for minimizing the entire power with the fixed transmission rates that is, the AMCS researched to date cannot be used in an actual system including users of both standpoints, because the conventional AMCS independently considers the two standpoints. Therefore, in a system including some users to which services requiring fixed transmission rate such as Video-on-Demand (VOD) are provided, it is unnecessary to maximize the transmission rates of all users as opposed to the RA problem. Therefore, a new adaptive modulation technique is necessary in consideration of such a problem.
In order to satisfy such a necessity, an optimal solution for the adaptive modulation problem can be obtained by expressing the adaptive modulation problem as a nonlinear optimization problem and then converting the nonlinear optimization problem into a linear optimization problem that can be solved by Integer Programming (IP). However, such a method for obtaining an optimal solution cannot be used in real-time because of the complexity of the method.

Method for allocating subchannels in an OFDMA mobile communication system

Korea Advanced Institute of Science and Technology


Methods and apparatus are provided for programmable active inductance. The disclosed active inductor devices provide a tunable bandwidth with improved linearity. The disclosed active inductors have a variable frequency response corresponding to a variable inductance of the active inductor. The active inductor comprises a variable resistive circuit having an effective resistance, wherein the variable resistive circuit is comprised of at least one resistor that can be selectively bypassed in the variable resistive circuit to vary the effective resistive. The active inductor has an inductance that can be varied by varying the effective resistance.

Active inductors are often used to extend the bandwidth of bandwidth-limited circuits, such as amplifiers employed in high frequency communication systems. The bandwidth of an active inductor-loaded amplifier (or buffer) is generally a function of the total output capacitance and resistance, along with an inductance "L" which, for an active inductor, is in turn a function of a resistance "R", parasitic capacitance, and transconductance of the transistor utilized to implement the active inductor.
A number of techniques have been proposed or suggested for tuning an active inductor utilizing a fixed resistance value such that a portion of the capacitive load is canceled (and the bandwidth is thereby extended). Process variations in the manufacturing of integrated circuits, temperature variations, and supply variations, however, often significantly affect the resulting resistance, capacitance, and transconductance of an active inductor circuit. Thus, the resulting available bandwidth is also subject to wide variations, despite any selection of resistance or capacitance values for fabrication.
U.S. patent application Ser. No. 10/929,843, entitled. "Three-Terminal, Tunable Active Inductor," assigned to the assignee of the present invention and incorporated by reference herein, discloses an active inductor circuit that is capable of being tuned to achieve a desired bandwidth, over process, temperature and supply variations. Generally, one embodiment of the disclosed active inductor circuit controls the gate voltages applied to one or more PMOS transistors to provide a variable resistance and thereby extend the bandwidth. While the disclosed active inductor circuit can be continuously tuned to achieve a desired bandwidth, it has been found that the range of resistance control required for some applications requires prohibitively large PMOS devices.
A need therefore exists for an improved active inductor device that provides a tunable bandwidth using digital control. A further need exists for an active inductor device that provides a tunable bandwidth with improved linearity.

Methods and apparatus for programmable active inductance


A method and apparatus for recording data concerning a system is provided. The apparatus comprises a memory card, such as a COMPACTFLASH card, and a processor unit, such as a T2CAS processor unit. The memory card includes a supplemental file that contains instructions as to what data is to be recorded and when the recording should start and stop. To conserve space the supplemental file is written as a sequence of hexadecimal characters whose position in the sequence and binary bit value indicates which data is to be recorded and when. A lookup table can be used to interpret the supplemental file. The processor unit includes or is coupled to a memory card reader/writer.

Complex machines, such as commercial and military aircraft, at times need to have various systems tested to ensure the machine is operating properly. For example, it is often necessary to test these machines under operating conditions and record data from these tests. When testing various systems of a complex machine, it is convenient to record data from certain inputs or outputs in order to obtain a record of system parameters. It is often of interest to start and stop the recording of certain inputs and outputs based on the condition of a system. For example, when testing systems on an aircraft, certain parameters indicative of the aircraft performance or the performance of a system might be of interest to record when the aircraft is operating between certain altitudes or at certain airspeed. However, current methods of recording such data have been limited.
Traditionally, to record information such as that generated by an aircraft and its various systems, bulky data recorders are attached to a serial output of a processor unit associated with the system and data is recorded. The use of this type of data recorder has several drawbacks. First, the data recorders are large and expensive. Also, the data recorders typically record all the signals from a given input or output, or all data from all inputs and output. There is no way to tell the system what data should be recorded and when recording should take place. This leads to the storage of unnecessary information and wasting of space on the recording medium. The bulky recorders are also not very portable and are not a convenient way to carry the data.
Therefore, a need has arisen for a recording method that both utilizes a recording medium that is compact and convenient to use a carry, but that also provides a way to easily specify what data is to be recorded and under what condition the recording should take place. The specification of what data to record and when to record the data should be done in such a way as to be easily changed by the user to record other data of interest. Therefore, what is needed is a method and system for recording system information.

Method and system for selectively recording system information

Aviation Communication & Surveillance Systems, LLC


A gravestone marker that includes a viewing chamber for receiving photographs and other small objects such as memorabilia honoring the deceased that includes a cement base frame with a hollow interior of a predetermined size and shape for placing on a concrete slab above the grave of the deceased, and a sheet of transparent bulletproof material that can be glass or plastic permanently attached by concrete epoxy adhesive to the concrete base frame forming a chamber beneath the transparent sheet. The chamber can receive photographs and other objects that can be viewed by persons standing at the gravesite. The strength of the transparent sheet of material can prevent vandalism or theft at the gravesite.

1. Field of the Invention
This invention relates to grave stone markers that may include granite, and specifically to a gravestone marker that includes a protected viewing chamber for photographs and small objects.
2. Description of Related Art
The use of gravestone markers to honor the memory of persons who have passed away, especially family members, using granite or other stone is well known in the prior art. While a granite tombstone or gravestone marker that is engraved with information is a time enduring memorial, it would be desirable to include memorabilia in addition to the tombstone to honor the love one that has passed away. For example it would be desirable to provide photographs and perhaps other small objects and memorabilia at the grave site that could remain there perpetually as long as the gravesite is there.
The invention described in this patent application accomplishes these objectives by providing a granite gravestone marker that includes a protected viewing chamber that includes a clear transparent cover of bulletproof material either glass or acrylic. The protected viewing chamber is also weatherproof, waterproof and moisture proof.

Grave stone marker with protected viewing chamber


The present invention relates to a process for producing a dioxazine compound represented by the formula (1) which comprises carrying out a ring closure reaction of a compound represented by the formula (2) in the presence of a dioxazine derivative of the formula (3), colored materials containing this dioxazine compound, and dioxazine compounds having a plate-like crystal form: ##STR1##

For preparing a compound of the formula (1) shown below, a process is known in which 3-amino-9-alkylcarbazole of the formula (5) shown below and chloranil are condensed in an inert solvent in the presence of an acid coupling agent to obtain a compound of the formula (2) shown below and this compound is subjected to ring closure using a ring-closing agent (PB Report 65,657, Japanese Patent Post-Exam Publication JP-B-60-11986, etc.). Also, processes such as disclosed in Japanese Patent Unexamined Publication JP-A-54-56630 and JP-A-58-120673 have been proposed for forming a pigment from its crude obtained according to the above process.
This pigment crude, however, is poor in dispersibility and requires strong dispersion for preparation of pigment, so that production efficiency is low and it is difficult to obtain a high-quality pigment from this crude. It has been proposed to pulverize the crude with a surfactant or a coloring matter derivative for a dispersion (JP-A-2-102272, JP-A-2-102273, U.S. Pat. No. 5,275,654, etc.). This method, however, still involves many problems such as low production efficiency, insufficient atomization and poor dispersion stability.

Process for producing dioxazine compounds, colored materials therewith and dioxazine compounds having a plate-like crystal form


A netting enclosure kit comprises a skeleton configured to operate in a plurality of configurations between a first, partially expanded configuration and a second, fully expanded configuration, a netting enclosure comprising a plurality of panels configured to be joined together to enclose or hang from the skeleton in each of the plurality of configurations, a first webbing configured to connect to a first portion of the netting enclosure, a second webbing configured to connect to a second portion of the netting enclosure, and a fastener configured to attached to the first webbing and to the second webbing to form an openable and closeable seam.

Animal pests can interfere with vegetable gardens by eating, damaging, or even destroying the plants prior to harvesting. Some approaches to this problem rely on synthetic chemicals applied to the plants and crops directly or onto the ground surrounding the plants. Other approaches rely on natural odors that would deter animal pests, such as the urine of predators. Many people prefer to grow their vegetables without chemicals, and even the natural odor products must be reapplied periodically, especially after rains.
Fencing products are also available, and are relatively easy to implement for preventing small animals, such as rabbits, from damaging garden plants. However, large animals, like deer, present a particular challenge because they can jump over, knock down, or pry open many of these fencing products. In general, fences must be at least eight feet tall to exclude deer. A fence of that height requires poles or posts sunk deeply into the ground for stability. In addition, covenant-controlled communities often restrict the height and style of permanent fence structures, making it impossible to erect an effective deer-proof fence.
There exists a need for a strong, stable and reasonably priced structure, easy to erect without installing poles or posts and easy to take down at the end of the season, wherein the structure is portable, reconfigurable, large enough to accommodate larger areas or compatible with smaller areas to meet the needs of casual gardeners, and attractive enough not to be challenged in covenant controlled communities.

Deer proof garden enclosure and method of making


The present invention provides a photosensitive member comprising an electrically conductive substrate having an anodized aluminum layer on the surface and a thick photosensitive layer on the substrate.

1. Field of the Invention
The present invention relates to a photosensitive member for electrophotography composed of a thick photosensitive layer, which is excellent in wear resistance and electrical characteristics, and can form good copy images without image-defects and image-roughness.
2. Description of the Prior Art
Known photosensitive materials for forming a photosensitive layer include inorganic photoconductive materials such as selenium, cadmium sulfide or zinc oxide. These photosensitive materials have many advantages such as low loss of charges in the dark, an electrical charge which can be rapidly dissipated with irradiation of light and the like. However, they have disadvantages. For example, a photosensitive member based on selenium is difficult to produce, has high production costs and is difficult to handle due to inadequate resistivity to heat or mechanical impact. A photosensitive member based on cadmium sulfide has defects such as its unstable sensitivity in a highly humid environment and loss of stability with time because of the deterioration of dyestuffs, added as sensitizer, by corona charge and fading with exposure. These photosensitive members have also a problem from the viewpoint of safety.
Many kinds of organic photoconductive materials such as polyvinylcarbazole and the similar compounds have been proposed for forming an organic photosensitive layer. These organic photoconductive materials have superior film forming properties, are light in weight, etc., but inferior in sensitivity, durability and environmental stability compared to the aforementioned inorganic photoconductive materials.
Various studies and developments have been in progress to overcome the above noted defects and problems. A function-divided organic photosensitive member of a laminated or a dispersed type has been proposed, in which a charge generating function and a charge transporting function are shared by different compounds. In usual, a photosensitive layer in the function-divided photosensitive member of the laminated type is composed of a charge generating layer containing an organic charge-generating material, a charge transporting layer containing an organic charge-transporting material and a binder resin. A photosensitive layer in the function-divided photosensitive member of the dispersion-type is composed of an organic charge-generating material and an organic charge-transporting material which are dispersed in a binder resin.
Such a function-divided organic photosensitive member can display performances excellent in electrophotographic properties such as chargeability, sensitivity, residual potential, durability with respect to copy and repetition, because most adequate materials can be selected from various materials. Moreover, function-divided photosensitive members have high productivity and low costs, since they can be prepared by coating, and suitably selected charge generating materials can freely control a region of photosensitive wavelength.
In particular, the function-divided photosensitive member of the dispersion-type can be used as a positively chargeable photosensitive member. The positively chargeable photosensitive member generates a little ozone and has an environmental resistance compared to a negatively chargeable photosensitive member. Therefore the function-divided photosensitive member of the dispersion-type has been paid to attention.
However, the organic photosensitive member is generally poor in mechanical strength and durability compared to the inorganic photosensitive member. A thickness of the organic photosensitive member decreases with its friction against toner, paper, a cleaning member and other similar loads in the copying machine. A layer-decreasing degree caused by wear depends on materials and mechanical systems, but generally it is 0.2-1 .mu.m after 10,000 times of copy. The decrease of the layer-thickness causes the deterioration of chargeability. When the deterioration is beyond tolerance limits, the lifetime of the photosensitive member is over. As a result, the organic photosensitive member is poor in resistance to copy.
Therefore, it has been developed and researched that a photosensitive layer is made thick in order to improve durability and to make the lifetime of the photosensitive member long.
However when the thickness of a photosensitive layer is merely made thick, electrical charges accumulate in the photosensitive layer after the repetition use, resulting in remarkable increase of residual potential, deterioration of chargeability and image-disorders.

Photosensitive member comprising thick photosensitive layer formed on anodized aluminum layer


Alpha crystalline form of strontium ranelate of formula (I):

Strontium ranelate, represented by formula (I):
or the distrontium salt of 5-[bis(carboxymethyl)amino]-3-carboxymethyl-4-cyano-2-thiophenecarboxylic acid, and its hydrates have very valuable pharmacological and therapeutic properties, especially pronounced anti-osteoporotic properties, making these compounds useful in the treatment and prevention of bone diseases.
Strontium ranelate and its hydrates also have properties making them useful in the treatment and prevention of arthrosis.

Abstract: characterised by its powder X-ray diffraction diagram and by a water content of from 22 to 24%.

Abstract: Medicinal products containing the same which are useful in the treatment of osteoporosis and arthrosis.


The method of invention involves the steps of placing a small hole in the flue of a furnace or the like; inserting the elongated probe of a CO tester in the hole; visually ascertain from the tester the CO content of the gas in the flue, comparing the measured CO content of the gas in the flue against a predetermined perimeter range of CO content between 0-45 ppm for furnaces, and 0-85 ppm for hot water boilers to determine the cleanliness of the combustible materials in the gas being combusted, and resealing the hole in the flue.

The combustion integrity of the flame to identify clean combustion in gas burning equipment in residential, commercial and light industrial facilities has heretofore been conducted by visual inspection of the flame. A qualified technician could make a visual observation of the flame and the residue left at the draft divertor, and some judgment could then reasonably be made as to the quality of the flame. Other than visual inspection, there has not been any equipment or special procedures to test for complete and clean combustion, particularly at levels to identify subtle problems that could be corrected inexpensively.
The Energy Conservation Act of 1987 required that all new equipment involving combustion must be fan assisted. In recent years, it has become apparent that a visual check by a technician of the flame was not good enough when fan assisted combustion was involved. Fan assisted combustion can be in the form of induced draft, or forced draft. Technicians have been missing or misdiagnosing many combustion problems because of reliance on visual identification. Sometimes with fan assisted combustion, the flame cannot be seen or cannot be easily seen. In many cases there is not even a small peep hole available for examination of the flame.
Sampling the flue for O.sub.2 or CO.sub.2 is not the answer to the foregoing problem because oxygen deficiency due to low combustion air flow is not one of the most common causes of poor combustion. In the majority of combustion problems, there is sufficient O.sub.2 left in the flue products. Thus, conventional equipment for sampling gases within the flue could not solve the problem.
When there is a problem in the combustion process, the CO levels increase. It doesn't matter if the source of the problem is oxygen deficiency, poor primary air entrainment, or flame impingement. Measuring CO levels may indicate the existence of a problem, but CO levels do not identify specific problems and it is not known within the industry what levels of CO signify trouble.
It is, therefore, a principal object of this invention to provide a method to identify the combustion integrity in fan assisted equipment.
A further object of this invention is to provide a method to identify combustion integrity of fan assisted equipment which can be easily and quickly practiced, and which can be economically conducted with existing equipment.
These and other objects will be apparent to those skilled in the art.

Method to identify gas combustion integrity in fan assisted equipment


A camera system uses a highly sensitive camera such as an intensified charge-coupled-device camera to acquire images. An image acquisition and processing tool can place the camera in a low-sensitivity mode and a high-sensitivity mode. In the low-sensitivity mode, a reference image may be acquired of a target that is illuminated by a light-emitting-diode. In the high sensitivity mode, low-photon-flux image data frames are acquired using a charge-coupled-device image sensor in the camera. The image acquisition and processing tool displays the acquired image data frames on top of the reference image in real time, so that a user is provided with immediate visual feedback. The image acquisition and processing tool has image preprocessing filters for enhancing image quality such as a sensor noise threshold filter, a cosmic ray filter, and a photon shape optimization filter. Pipeline filters may be used to further process acquired image data frames.

This invention relates to image acquisition and processing, and more particularly, to the acquisition and processing of low-photon-flux images.
Cameras have been developed that are sensitive to low light levels. Cameras of this type may be used in a variety of fields. As an example, cameras that are sensitive to low light levels may be used in biological studies such as studies in which luminescence or florescence is measured. Some biological studies that involve low light level measurements involve monitoring bioluminescent targets. Bioluminescent targets may include live animals and other biological specimens.
Accurate studies require sensitive cameras. However, even if a highly sensitive camera is used to capture images, image data can be obscured by noise. Moreover, conventional measurement schemes generally require long integration times before signal strengths have developed sufficiently to be displayed for a user. During the long capture times associated with such schemes a background image can be displayed, but no low-light image data can be presented. After completion of an exposure that is long enough for a low-light image to build up its signal strength above noise obscuration levels, low-light image data can be displayed, but until the long exposure is complete, there is no way to provide visual feedback of low-light image data to the user.
It would therefore be desirable to provide improved image acquisition and processing systems that handle low-light imaging applications.

Low-photon-flux image acquisition and processing tool


A flashlight has a water tight cylindrical battery casing and a sealed cylindrical closure which screws over the forward open end thereof. The closure includes a lens and a parabolic reflector. A first PC board fixed in the closure serves as a support member for a second PC board that serves as a mounting member for a pair of bulbs. The second PC board is pivotally connected to the first PC board in front thereof in overlapping fashion. The pins of the bulbs are plugged into forward opening pin receptacles in the second PC board. The second PC board can swing back and forth to move the bulbs through an arcuate slot in the reflector into and out of the focal point of the reflector. A manual actuator located on the outside of the casing can be toggled by a diver's hand and its motion is carried by a sealed linkage through the casing to pivot the second PC board. This allows the diver to selectively position a spare one of the two bulbs in the focal point of the reflector in case the bulb in use fails or to select a bulb with a higher intensity. This same motion also completes an electrical circuit through the two PC boards between the selected bulb and the battery so that the selected bulb is energized. A lamp head of the aforementioned configuration without batteries may be connected through a conductor cable to a separate battery pack having an ON/OFF switch.

The present invention relates to flashlights and pertains particularly to an improved flashlight having multiple selectable bulbs.
Handheld flashlights are widely used as a primary source of light in many remote locations, especially where access to electrical distribution networks is not available. They have their own power source typically in the form of one or more batteries. Simpler, less expensive flashlights typically employ a number of small cylindrical alkaline batteries disposed end to end in a small diameter cylindrical housing. Most high powered, more expensive lights typically employ groups of dry cell batteries in arrays making up six or twelve volts in larger housings. Others employ larger single cubic shaped dry cell batteries which are typically six or nine volts. These lights usually have a handle attached to and extending outward from the housing shaped to provide a comfortable hand grip.
The electrical circuit of a conventional flashlight comprises a battery and a single light bulb positioned in a reflector with electrical conductors connecting the battery to the bulb and a switch for selectively interrupting and completing the circuit to energize the bulb and activate the light.
Reliable flashlights are essential tools for divers who routinely encounter reduced visibility under water. A flashlight must be reliable so that the diver is not likely to be left without a light should a component of the light, such as the bulb, fail. It should also be reasonably easy to carry and manipulate in view of the heavy protective clothing and gloves often worn by a diver.
Divers also frequently encounter different conditions while diving which require different light intensities in order to effectively illuminate an area of interest. It is well known that certain light sources (e.g. halogen) better penetrate certain types of water conditioner atmosphere than others.
Accordingly, there is a need for a flashlight having multiple selectable bulbs in order to provide a backup source in case of failure of one bulb and/or multiple bulbs of different illumination amounts.


A magnetic tunnel junction device with perpendicular magnetization including a reference layer, a tunneling dielectric layer, a free layer and a capping layer is provided. The tunneling dielectric layer covers on the reference layer. The free layer covers on the tunneling dielectric layer. The capping layer is consisted of magnesium, aluminum and oxygen, and disposed on the free layer.

Perpendicular magnetic anisotropy (PMA) spin-RAM have advantages such as an ability of scalability, a low power consumption, a high performance and a high reliability, and thus is very likely to become a mainstream technique of the next-generation new non-volatile memory. However, to enhance a magnetoresistance ratio of devices and to reduce write currents, a free layer still has to be mainly composed of films of perpendicularly magnetized CoFeB or CoFe. Nonetheless, since such free layer has a low equivalent magnetic anisotropy coefficient (Keff) and a small thickness, a thermal stability thereof is low; thus, the free layer fails to be a non-volatile memory. Therefore, it is proposed lately in literature that improvements to a thermal stability of the CoFeB or the CoFe free layer may be enhanced by using double layer of MgO. However, a process temperature thereof needs to be lower than a temperature for CMOS back-end-of-line (BEOL) process, otherwise a device characteristic may suffer a degradation. Accordingly, how to improve a heat resistance for the magnetic tunnel junction device with perpendicular magnetization is now an important issue to be solved in the field.

Magnetic tunnel junction device with perpendicular magnetization and method of fabricating the same

Industrial Technology Research Institute


A machine (100) for making filter bags (1) for infusion products, the machine (100) being of the type comprising, one after the other along a production line (P), a plurality of operating stations designed to form the filter bags (1) and at least one operating outfeed station (7) for handling the filter bags (1) made; the operating outfeed and handling station (7) comprises conveying means (8) designed to successively pick up and withhold the filter bags (1) along a certain section (T1) of the line (P); supporting guide means (9) along which an ordered and continuous succession of filter bags (1) is formed and fed along another section (T2) of the line (P); and means (11) for picking up and transferring the filter bags from the conveying means (8) to the supporting guide means (9).

Usually, automatic machines for packaging/making filter bags comprise a plurality of operating stations located one after the other along respective production lines where the filter bags are made, each filter bag containing a charge of infusion product enclosed in a chamber of the filter bag.
Depending on the type of product and machine, the filter bags may have one or two chambers and may be associated, using any of several known methods (such as knotting, heat-sealing or application of heat-sealable stamp) with a tie string that connects the filter bag to a tag joined to the free end of the string in any of several different ways (for example, knotting, heat-sealing or application of a stamp).
The tie string and tag are placed on the filter bag (for example, wound around the filter bag or placed between the two chambers) to form a product that is ready to be grouped and suitably stacked in the area at the end of the production line where there is a filter bag stacking station, usually followed by a final packaging station which places the stacks or groups of stacks of filter bags in suitable containers or cartons. In many cases, before the filter bags are stacked, they are overwrapped with individual wrappers, each suitably folded into the shape of a U around a filter bag and sealed to form the typical envelope-like packet containing the filter bag.
At present, depending on circumstances and on the place where the tea-bag making machine is to be used, especially if low-cost labour is available, manufacturers of automatic tea-bag machinery are opting more and more for "simplified" solutions, where the filter bags are packaged manually, thus avoiding the need to provide machines with automated end-of-line packaging stations and thus reducing costs and saving factory floor space.
For this purpose, the tea bag malting machine must be provided with an end-of-line station designed to feed out the filter bags (with or without overwrap) at a regular rate, in succession, at some distance from the machine, and in such a way that production operators can easily pick them up manually.
In addition to this, the outgoing filter bags must be divided up into well-defined successive groups along the feed line of the end-of-line station (each group containing a predetermined number of filter bags which may, however, be changed when necessary), so that the operator can pick them up easily and without hesitation, knowing exactly that the groups contain the right number of filter bags to be placed in the cartons.
The Applicant's aim was therefore to design an automatic machine for malting filter bags for infusions products, whose structure comprises an end section with a product outfeed station adapted to form groups containing predetermined numbers of filter bags which can be picked up manually, without altering the basic structure and productivity of the machine and maintaining the machine's high level of performance, dependability and adaptability.

Automatic machine for making filter bags for infusion products


The present invention is directed to a mothod for preventing the formation of additional surface stains on destained steel sheet processed in a continuous pickle line operation.

1. Field of the Invention
This invention is directed to continuous pickling operations, and in particular, it is directed to apparatus and a method for improving surface quality in continuous hot-rolled steel sheet product by removing surface stains that may appear on the finished steel product if the pickling line needs to be stopped for any one of a variety of reasons. For example, during normal pickling operations new coils of steel sheet product are repeatedly spliced onto the trailing end of sheet steel product running through the pickle line. If the length of the sheet steel product held within the looper section of the line is not long enough to provide the necessary time to complete the splice, the line must be stopped. Additionally, pickle lines are routinely stopped for unscheduled maintenance and/or repair. They are also stopped to make minor line adjustments, and at times are even stopped because of power failures. During such line stops, long sections of pickled and partially pickled steel sheet product, for example up to 100xe2x80x2 or more in length, are disproportionately exposed to the pickle liquor and/or acid fume above the pickling tanks. Such prolonged exposure results in the reformation of iron oxides, or stains, onto the surface of the sheet product.
2. Brief Description of the Related Art
Various attempts have been made in the past to remove stains from pickled sheet steel product. One such past attempt is disclosed in U.S. Pat. No. 5,916,379 granted to Varley, et al. The patent is directed to a composition and method of using the composition to prevent surface staining (flash rusting) on steel sheet in a continuous pickling line. The inventors disclose using an aqueous solution comprising about 3%-15% by weight each of gluconate and citrate to prevent the formation of flash rust during a line stop. The rust inhibiting solution is applied in the rinse zone of the pickle line. Such rinse zone stain removers are referred to in the art as xe2x80x9cpost-treatmentxe2x80x9d stain removers.
Another post-treatment stain remover process, disclosed in U.S. Pat. No. 5,837,061, prevents formation of hydrolysis stains on sheet steel product. The post-treatment process includes proving an inert gas or CO2 atmosphere in the rinse zone of the pickle line to prevent staining.
A third Patent, U.S. Pat. No. 5,296,042, recognizes various problems associated with staining in pickling operations. The Patent teaches that although many compositions are known to remove stain from sheet steel, it is extremely difficult to effectively apply stain-removing compositions to sheet steel surfaces in a continuous high speed manufacturing line. The inventors further state that when hot rolled sheet steel is pickled with HCl, the product can suffer from iron and chloride staining during line stops, and that the efficiency of stain removing chemicals is directly related to rinsing techniques. The Patent teaches that xe2x80x9crinsing is of major importancexe2x80x9d in any process that attempts to remove the residual chloride ions that contribute to the formation of stain on pickled stain surfaces.
Another U.S. Pat. No. 4,389,254, discloses that when inorganic acids are used as a pickle liquor, it tends to cause surface marks and pitting on the steel sheet product. In order to overcome this problem, the inventors use carefully selected organic pickle liquor in their pickle tanks, for example formic acid, acetic acid, or citric acid.
U.S. Pat. No. 4,361,444 discloses a post pickling rinse process that includes a rapid and uniform air drying step to prevent water spotting on strip.
Finally, U.S. Pat. No. 1,902,815 is directed to a process for pickling sheet steel in a sulfuric acid bath at a temperature of about 200xc2x0 F. The pickled product is then squeezed between wringer rolls, rinsed with water sprays, and the rinsed sheet is given a final wipe between a last set of wringer rolls. A blast of hot air from upper and lower air blast nozzles provides a final drying step. The Patent discloses providing a continuous forced blast of hot air against the sheets to dry all water from both surfaces.
It appears that the more effective stain removing processes developed in the past include a post-treatment stain remover used in combination with spray or immersion type rinse steps. We have found, in actual continuous hot rolling operations, that such past stain removing processes still fail to completely remove all surface staining caused by pickle line stops. For instance, we have found that even the best post-treatment stain removers tend to leave about a 1-inch wide brown stain along both edges of the pickled sheet after the drying step is completed. It is believed that such staining is caused by the retention of residual stain remover solution along the edges of the continuous pickled sheet steel product after the drying operation is completed. We have also discovered that when we use such post-treatment stain removers in combination with an improved post-rinse strip drying process developed at our operation, stain removal is improved to where the 1-inch brown stain is completely removed or at least reduced to where it has little effect on the product. For example, when we use a post-treatment stain remover, such as a new Crown formula sold as (NCI-SRU), in combination with the improved air knife arrangement and drying-process of the present invention, the 1-inch brown stain is completely removed. The new air knife arrangement is located downstream of the last wringer roll in of the line, and it delivers a fan shaped blast of drying air that radiates outward from the center of the steel sheet product toward both continuous edges of the sheet. The blast of drying air from the air knives impacts upon the last wringer roll to prevent water xe2x80x9cdrag-outxe2x80x9d along the downstream edge of the roll, and the outward radiating blast of drying air drives any excess rinse toward and off the continuous edges of the pickled sheet product.
It is therefore an object of the present invention to provide an improved process for removing stains from a pickled sheet product.
It is a further object of the present invention to provide an improved rinse/dry process that eliminates edge staining on a pickled sheet product.
It is another object of the present invention to provide an improved spray and air knife arrangement that removes residual stain remover solution from the edges of a pickled sheet product.
In satisfaction of the foregoing objects and advantages, the present invention provides a continuous pickle line that includes an improved air knife arrangement adapted to provide an airflow along the surface of a continuous steel sheet processed in the continuous pickle line. The airflow impacts against the exit side of the roll gap located between a set of wringer rolls that contact the continuous steel sheet, and the force of the airflow impacting against the roll gap is sufficient to prevent rinse water drag-out between the set of wringer rolls and onto the dried surface of the continuous sheet being processed. The airflow in combination with a post-treatment stain remover applied in the rinse zone of the continuous pickle line improves surface quality when the continuous sheet being processed is subjected to a line stop.

Process for removing stains from steel sheet in a continuous pickling line


In a turbine bucket having an airfoil portion and a root portion with a platform at an interface between the airfoil portion and the root portion, a platform cooling arrangement including: a cooling passage defined in the platform to extend along at least a portion of a concave, pressure side of the airfoil portion, at least one cooling medium inlet to said cooling passage extending from an airfoil cooling medium cavity in a vicinity of an axial center of the airfoil portion, and at least one outlet opening for expelling cooling medium from said cooling passage.

The present invention relates to a novel cooling system for increasing the useful life of a turbine bucket.
A gas turbine has (i) a compressor section for producing compressed air, (ii) a combustion section for heating a first portion of said compressed air, thereby producing a hot compressed gas, and (iii) a turbine section having a rotor disposed therein for expanding the hot compressed gas. The rotor is comprised of a plurality of circumferentially disposed turbine buckets.
Referring to FIG. 1, each turbine bucket 10 is comprised of an airfoil portion 12 having a suction surface and a pressure surface; and a root portion 14 having structure 18 to affixing the blade to the rotor shaft, a platform 16 from which said airfoil extends, and a shank portion 20.
The platforms are employed on turbine buckets to form the inner flow path boundary through the hot gas path section of the gas turbine. Design conditions, that is gas path temperatures and mechanical loads, often create considerable difficulty to have bucket platforms last the desired amount of time in the engine. In this regard, the loading created by gas turbine buckets create highly stressed regions of the bucket platform that, when coupled with the elevated temperatures, may fail prior to the desired design life.
A variety of previous platform cooling designs have been used or disclosed. Referring to FIG. 2, one previous platform cooling design was based on utilizing the cavity 122 formed by adjacent bucket shanks 120 and platforms 116 as an integral part of the cooling circuit. This type of design extracts air from one of the buckets internal cooling passages and uses it to pressurize the cavity 122 formed by the adjacent bucket shanks 120 and platforms 116 described above. Once pressurized, this cavity can then supply cooling to almost any location on the platform. Impingement cooling is often incorporated in this type of design to enhance heat transfer. The cooling air may exit the cavity through film cooling holes in the platform or through axial cooling holes which then direct the air out of the shank cavity. This design, however, has several disadvantages. First, the cooling circuit is not self contained in one part and is only formed once at least two buckets 110 are assembled in close proximity. This adds a great degree of difficulty to pre-installation flow testing. A second disadvantage is the integrity of the cavity 122 formed between adjacent buckets 110 is dependent on how well the perimeter of the cavity is sealed. Inadequate sealing may result in inadequate platform cooling and wasted cooling air.
Another prior art design is disclosed in FIGS. 1(a) and 5(a) of U.S. Pat. No. 6,190,130. This design uses a cooling circuit that is contained fully within a single bucket. With this design, cooling air is extracted from an airfoil leading edge cooling passage and directed aft through the platform. The cooling air exits through exit holes in the aft portion of the bucket platform or into the slash-face cavity between adjacent bucket platforms. This design has an advantage over that described above and depicted in FIG. 2 in that it is not affected by variations in assembly conditions. However, as illustrated therein, only a single circuit is provided on each side of the airfoil and, thus, there is the disadvantage of having limited control the amount of cooling air used at different locations in the platform. This design also has the disadvantage of restricting the cooling air supply to the leading edge cavity.
Yet another prior art cooling circuit configuration is disclosed in FIG. 3(a) of U.S. Pat. No. 6,190,130 and also in U.S. Pat. No. 5,639,216. This design also uses a cooling circuit fully contained within a single bucket, but it is supplied by air from underneath the platform, i.e. shank pocket cavity or forward wheel space (disc cavity).

Bucket platform cooling circuit and method


Provided herein is an apparatus, including a spinstand configured to position a disk in a testing orientation and a motor coupled to the spinstand, configured to rotate the disk. The motor comprises a fluid dynamic bearing.

In order to test the reliability of a head-disk interface engineers employ spinstands that allow for component-level reliability testing. Spinstands employ a motor to spin the disk and an adjustable mount on which to affix the read-write head, suspension, or head stack assembly ("HSA"). Currently, spinstands use ball bearing-based motors to spin the disks, and the ball bearing-based motors are very expensive to replace. Ball bearing-based motors inherently have radial runout issues that lead to increasingly less accurate radial positioning of the head on the disk. Ball, race, and cage modes all significantly contribute to this radial runout. Furthermore, ball bearing-based motors employ oil and/or grease in the bearings that can outgas, which can contaminate the head-disk interface being tested. Moreover, seals on ball bearing-based motors can rub, creating particulate contamination in the process. Such particulate contamination may render the reliability test worthless because the reliability test is meant to stress the head-disk interface without the influence of external contamination.

Spinstand with motor having fluid dynamic bearing


Disclosed are polymers which include tertiary aryl amine moieties that can function as hole transport agents and which also have reactive silane groups thereon capable of being condensed to a silsesquioxane composition, as well as the silsesquioxane compositions prepared therefrom. The silsesquioxanes can be coated onto substrates to form abrasion-resistant layers having hole transport properties useful in devices that require charge transport properties, such as light-emitting diodes and organic electrophotographic elements such as photoreceptors or photoconductors. Also disclosed are electrophotographic elements which comprise an electrically conducting layer, a charge generating layer overlying the electrically conducting layer, and a charge transport layer overlying the electrically conducting layer. The charge transport layer, which can be an overcoat overlying the charge generating layer, comprises the condensed reaction product of the disclosed polymers.

Organic polymers are used for charge transport in devices such as organic light-emitting diodes (OLED) and organic electrophotographic photoreceptors or photoconductors (OPC). In OLEDs charge is injected from an electrode into a charge transporting layer, in an OPC the charge is photogenerated and subsequently injected into the charge transport material dissolved in, or a functional part of, an organic polymeric material which serves as the binder. In these devices, the aim is for charge to be transported, in the absence of trapping, from the site of injection to the counter electrode, driven by the applied field.
In charge generating elements, incident light induces a charge separation across various layers of a multiple layer device. In an electrophotographic charge generating element, also referred to herein as an electrophotographic element, an electron-hole pair produced within a charge generating layer separate and move in opposite directions to develop a charge between an electrically conductive layer and an opposite surface of the element. The charge forms a pattern of electrostatic potential, also referred to as an electrostatic latent image. The electrostatic latent image can be formed by a variety of means, for example, by imagewise radiation-induced discharge of a uniform potential previously formed on the surface. Typically, in the electrophotographic process the electrostatic latent image is developed by contacting it with an electrographic developer to form a toner image, which is then fused to a receiver. If desired, the latent image can be transferred to another surface before development, or the toner image can be transferred before fusing.
In an electrophotographic process, the photoreceptor is typically subjected to a variety of physical and chemical abuses, such as scratching, abrasive wear and exposure to chemicals, e.g., ozone and nitrogen oxides, from corona charging. Organic photoreceptors are typically easily damaged by these abuses and their useful lifetime thereby can be decreased. The surface of an organic photoreceptor can be relatively soft, so that cleaning, by blade or brush, causes scratches and abrasive wear. Unintended contacts of the surface with sharp objects may also result in scratches that necessitate photoreceptor replacement. The photoreceptor surface is also relatively permeable and its components are reactive towards the ozone and nitrogen oxides generated during corona charging. After extended exposure to such chemicals, the electrophotographic characteristics may degrade to the point where image defects become objectionable and the photoreceptor must be replaced. Organic photoreceptors are also susceptible to photochemical damage from ultraviolet radiation emitted from the corona discharge or from exposure to room light. As a result of these factors, the lifetime of an organic photoreceptor is on the order of one hundred thousand cycles. By contrast, a lifetime of one million cycles is typical of the much harder amorphous selenium and arsenic triselenide photoreceptors. Extensive efforts have been devoted in attempts to stabilize organic photoreceptors from such abuses.
Overcoating the photoreceptor with a tough and chemically impervious overcoat layer is one approach that has been utilized to extend their useful life, such as with the materials disclosed in U.S. Pat. Nos. 5,204,201; 4,912,000; 4,606,934; 4,595,602; 4,439,509; and 4,407,920. If they are used, an overcoat should desirably bind well to the underlying photoreceptor materials, not be too brittle such that it cracks in an electrophotographic process, coated in a relatively very thin layer, and transport charge to prevent unwanted charge build up during electrophotographic process cycling. The resistivity of an overcoat has important consequences in an electrophotographic system. If the overcoat has high resistivity and inadequate capability to transport holes, the time constant for voltage decay will be excessively long relative to the processing time for the electrophotographic element, and the overcoat will retain an undesirably high residual potential after photodischarge of the underlying photoreceptor. The magnitude of the residual potential depends upon the initial potential, the dielectric constants of the various layers, the thickness and the charge transport characteristics of each layer. A solution to high residual potential has been to reduce the thickness of the overcoat layer. Another solution is to provide an overcoat that is conductive. The overcoat should not, however, be too conductive. The electrophotographic element should be sufficiently electrically insulating in the dark that the element neither discharges excessively nor allows an excessive migration of charge along the surface of the element. An excessive discharge ("dark decay") would prevent the formation and development of the latent electrostatic latent image. Excessive migration causes a loss of resolution of the electrostatic image and the subsequent developed image. This loss of resolution is referred to as "lateral image spread." The extent of image degradation will depend on the processing time for the electrophotographic element and the thicknesses and dielectric constants of the layers. It is thus desirable to provide an overcoat that is neither too insulating nor too conductive so as to meet the objectives previously mentioned.
The triboelectric properties of the overcoat should also desirably be matched to the triboelectric characteristics of the electrophotographic toner used to develop the electrostatic latent image. If the triboelectric properties are not matched well enough, the electrophotographic element will triboelectrically charge against the electrophotographic toner. This causes disruption of the charge pattern of the electrostatic latent image and can result in background in the resulting toner image. For example, an overcoat can triboelectrically match a particular negatively charging toner, but not triboelectrically match another toner that charges positively.
Silsesquioxanes generally are a class of silicone polymers that have been used as abrasion resistant coatings, including a coating for organic photoreceptors. Such organic silicone coatings are normally prepared by a sol-gel process. Certain silsesquioxane overcoat layers for organic photoreceptors are disclosed in U.S. Pat. Nos. 5,731,117; 5,693,442; 5,874,018; and 6,066,425. The protection of organic photoconductors using an overcoat of polysiloxane mixtures in a polycarbonate resin is described in U.S. Pat. No. 6,030,736.
Charge transport materials (CTMs) have also been added to polymeric binder layers to transport charge in organic photoreceptors. These layers are in general insulators that carry charge when either holes or electrons are injected into them. U.S. Pat. No. 3,542,544 discloses triphenylmethanes and tetraphenylmethanes substituted with dialkylamines as CTMs that are incorporated into photoconductive elements. Triphenylmethane CTMs containing hydroxyaniline groups are described in U.S. Pat. No. 5,368,967. Electrophotographic photoreceptors in which triarylamine compounds with dihydroxy substituents are covalently bonded into polycarbonate resins are disclosed in U.S. Pat. No. 5,747,204. Arylamines incorporated into silsesquioxanes as acid scavengers for photoreceptors is discussed in U.S. Pat. No. 6,187,491. The incorporation of triarylamines in a functional subunit of a composition that also includes an inorganic glassy network subunit and a flexible organic subunit is discussed in U.S. Pat. No. 5,116,703. Imaging members containing hole transporting polysilylene ceramers are described in U.S. Pat. No. 4,917,980.
The incorporation of tertiary arylamines into silsesquioxane polymers for the purpose of transporting holes has been mentioned in U.S. Pat. Nos. 5,688,961; 5,712,360; 5,824,443; 5,840,816; 5,888,690, 5,905,008; 5,910,272, and 6,376,695. Another synthesis method is described in U.S. Pat. No. 6,046,348. In U.S. Pat. No. 6,517,984 by Ferrar et al., the teachings of which are incorporated herein by reference in their entirety, certain silsesquioxane compositions are disclosed containing hydroxy tertiary arylamines for hole transport. Three related U.S. Patents are U.S. Pat. Nos. 6,143,452; 6,203,692, and 6,265,122.
Recent articles in the chemical literature have discussed sol-gel networks, including silsesquioxanes, that have useful moieties, such as organic dyes, attached to the siloxane network through non-hydrolysable Si—C bonds, and equilibrium control addition through Si—O—C bonds. For example, E. Bellmann et al. reported the incorporation of a functional moiety, i.e., fluorinated tertiary arylamines and trimethoxyvinylsilane into polymer chains (Chem. Mater., 2000, Vol. 12, p. 1349); however, due to low reactivity of trimethoxyvinylsilane in radical polymerization, the amount of silane moieties incorporated into the resulting polymer is limited. Perylenes are said to be incorporated into sol-gel networks by first coupling them to the silane and then forming a sol-gel network, as described in M. Schneider and K. Mullen, Chem. Mater., 2000, Vol.12, p 352. Alternatively, a dye is said to be incorporated in the sol-gel formation process, as described in C. Sanchez and F. Ribot, New J. Chem., 1994, Vol.18, p 1007.; C. Sanchez, F. Ribot, B. Debeau, J. Mater. Chem. 1999, 9, 35.; F. Ribot and C. Sanchez, Comments on Inorganic Chemistry, 1999, Vol. 20, p 327; and T. Suratwala et al., Chem. Mater., 1998, Vol.10, p199.
However, there are several drawbacks for previously employed silsesquioxane overcoat layers. First, these silsesquioxane polymers are not entirely compatible with many commonly used organic materials employed for other functional layers in OPCs, and therefore, the overcoat layers do not bond well with other organic materials employed in such photoreceptors and easily peel off. Second, the organic silicone overcoat layers are usually brittle and crack under bending and mechanical fatigue. Third, due to the lack of charge transport properties, the silsesquioxane overcoat layers can build up high residual voltage during the electrophotographic process. Modifications of silsesquioxane materials have been developed, but generally do not overcome these weaknesses. As can be seen, it would be desirable to develop silsesquioxane polymers with improved physical and chemical properties which could be used as a sol-gel precursor for preparation of relatively hard, protective coatings having hole transport capabilities that would be desirable for use in electrographic elements.

Organic charge transporting polymers including charge transport moieties and silane groups, and silsesquioxane compositions prepared therefrom


A self-locking orthodontic bracket having a body with an archwire slot, and a locking slide member which is movable to open and close the slot. Archwire retention is provided by the slide member without use of conventional ligatures or tie wires. A resilient member is provided to retain the slide member in either the open or closed position, while preventing excessive sliding movement which could disengage the slide member from the bracket body.

Orthodontic treatment of improperly positioned teeth involves the application of mechanical forces to urge the teeth into correct alignment. The most common form of treatment involves use of orthodontic brackets which are small slotted bodies configured for direct cemented attachment to the labial or lingual surfaces of the teeth, or alternatively for attachment to metal bands which are in turn cemented or otherwise secured around the teeth.
A resilient curved archwire is then seated in the bracket slots, and the archwire is bent or twisted before installation whereby the restoring force exerted by the seated resilient wire tends to shift the teeth into orthodontically correct alignment. Depending on the shape of the archwire (both round and rectangular cross sections are in common use) and the orientation of the bracket slot, it is possible to apply forces which will shift, rotate or tip the teeth in any desired direction.
Conventional orthodontic brackets include tie wings around which small ligature wires are tied to hold the archwire in a securely seated position in the brackets. Ligatures or some other form of fastening means are essential to insure that the activated archwire is properly positioned around the dental arch, and to prevent the wire from being dislodged from the bracket slots during chewing of food, brushing of the teeth, or application of other forces to the wire by the patient.
Orthodontists are skilled in the manipulation of ligatures, but the placement of these small wires nevertheless requires considerable time during initial installation of an archwire. It is also normally necessary to remove and replace the ligatures at one or more intermediate stages of orthodontic treatment involving sequential use of several different kinds of archwires, leading to further essentially unproductive chair time for the orthodontist and possible discomfort for the patient.
Ligatures also tend to make proper oral hygiene more difficult as the wires can trap food particles, and the twisted ends of a ligature may be shifted during chewing into a position where irritation of the patient's gums or cheek tissue occurs. Broken or dislodged ligatures may also require emergency patient visits to the orthodontist, and broken ligatures further present the hazard that a loose piece of wire may be swallowed or inhaled into the patient's breathing passages.
Many of the problems presented by ligatures are overcome by self-locking orthodontic brackets which in many cases eliminate need for these tie wires. One approach to a self-locking design involves use of a rotatable locking member which is coupled to the bracket, and is movable to open and close the bracket slot, the archwire being held captive in the slot when the locking member is in the closed position. Bracket configurations of this type are disclosed in my U.S. Pat. Nos. 4,077,126, 4,371,337, 4,419,078 and 4,559,012.
The present invention is directed to a different style of self-locking bracket using a sliding member which is linearly movable in an occlusogingival direction to open and close the bracket archwire slot. This new design has a desirably low profile when mounted on a tooth, and features a detent retention in both the open and closed positions, and with greatly increased resistance to complete removal of the slide member from the bracket body.
The new bracket eliminates any need for time-consuming archwire ligation in a high percentage of cases, and lock-pin sockets are provided to enable ligation in an occasional situation where the archwire cannot be initially seated due to a badly malpositioned tooth. The bracket is smoothly contoured to minimize food-trapping recesses, and is useful in both light-wire and edgewise techniques without restriction on archwire cross section. The bracket is also useful in straight-archwire techniques where desired force vectors (e.g., torque, tip and rotation) are designed into the bracket.


An injection mold including a connecting structure for separating confronting faces of a slide member and a mold base, respectively, during a movement of the slide member. In accordance with several embodiments of the invention, the connecting structure may include a compressible member such that the slide member is biased away from the mold base, and wherein a positive contact between the confronting surfaces is configurable in response to an applied clamping force between the slide member and the mold base. In accordance with an alternative embodiment of the invention a cam arrangement links the slide member and the mold base enabling a positive contact between the confronting surfaces when the slide member is arranged in the in-mold position, and providing a gap between the confronting surfaces during at least a portion of an interval when the slide member is moving.

U.S. Pat. Nos. 5,736,173 and 6,569,370 disclose a preform injection mold including a stripper plate that supports a wear plate on its upper surface. Opposed slide bars, having neck rings mounted thereon, are slidably supported by the wear plate.
U.S. Pat. No. 6,450,797 discloses molding apparatus including a pair of slide bar inserts that are laterally movable into and out of engagement with other mold components.
U.S. Pat. No. 6,799,962 discloses a stripper assembly for an injection molding machine. The assembly comprises a slide bar pair consisting of a first slide bar and a second slide bar. Transmission means is operatively coupled to the first slide bar and the second slide bar to transform movement of the first slide bar in one direction into movement of the second slide bar in an opposite direction.
FIG. 1 is a cross-sectional view through a portion of an injection mold of U.S. Pat. No. 6,569,370. Generally, the mold is shown to include a mold base 16 comprising a core plate 3, a stripper plate 17, and a cavity plate 10, having a stack 1 of molding inserts arranged therein. FIG. 1 shows the mold in a mold-closed position ready for injection of the plastic into the mold. The stack 1 includes a mold core 2 fitted into the core plate 3 and retained therein by a lock ring 4 and bolts 5. The mold core 2 contains a cooling tube 6 for the transmission of cooling fluid from a source within the core plate 3 to remove heat from the injected material in the mold cavity 7 and solidify the molded part in the mold cavity 7. The stack 1 comprises a set of complementary molding inserts including a cavity insert 8 and an adjacent gate insert 9 that are retained in the cavity plate 10 by a cavity flange 11 and bolts (not shown). Cooling channels 12 circulate cooling fluid from a source through the cavity insert 8 and gate insert 9 to remove heat from the injected material. The mold base 16 also includes a pair of slide bars 15A and 15B that are slidably supported on a wear plate 19, itself mounted on the stripper plate 17. The slide bars 15A, 15B are configured for carrying a pair of neck rings 13 and 14 of the mold stack 1 between an in-mold position and an out-mold position. The wear plate 19 is sacrificial material and reduces the wear between the slide bars 15A, 15B and the stripper plate 17 when the neck rings 13 and 14 are moved apart by the slide bars 15A, 15B to release a molded part from the mold cavity 7. Cooling channels 18 circulate cooling fluid from a source through the neck rings 13 and 14 to remove heat from the injected material. Molten material is conveyed to the mold cavity via a hot runner nozzle, hot runner manifold and hot runner stacks.
FIG. 2 is a partial perspective view of a known slide bar and stripper assembly that may be used with the stack 1 of FIG. 1. In this assembly, the slide bars 21A and 21B are linked to the mold by a connecting structure 61 that includes connecting bars 22A and 22B, respectively, and a pair of gibs 23A and 23B bolted to the stripper plate 25, for slidably arranging the connecting bars 22A and 22B in a guide that is preferably provided as a groove 26 configured in the stripper plate 25. The connecting bars 22A and 22B travel along the stripper plate groove 26 to activate the slide bar 21A and 21B, between an in-mold and an out-mold position, to open and close the neck rings in the mold. For purposes of illustration, a single pair of neck rings 20A and 20B is shown. Wear plates 27, 28 are located between the slide bars 21A and 21B and the stripper plate 25 to reduce wear of the slide bars 21A and 21B and stripper plate 25. Because the wear plates 27, 28 do wear, clamping force cannot be reliably applied therethrough but instead passes along the mold stack. When the clamping force A (see FIG. 1) going through mold stack 1 becomes so high that it could start to wear stack components, it becomes necessary to add clamping force blocks 29, shown with reference to FIG. 1, outside the immediate area of the mold cavities to take excess clamping force.
As shown in FIG. 2, in the prior art, gibs 23A, 23B are attached to the stripper plate 25 to constrain the connecting bars 22A and 22B within the groove 26. The gibs 23A, 23B are made from a stiff material such as an aluminum-bronze extruded bar stock sold under the registered trade mark 'Ampco 18' by Ampco Metal S. A. Corp of Switzerland (i.e. Young's Modulus of about 117 GPa). When the connecting bars 22A and 22B are moved along the groove 26, a corresponding movement of the slide bars 21A and 21B, linked thereto, between the in-mold and the out-mold positions, causes the neck rings 20A and 20B, respectively, to move between an open and a closed configuration. The connecting bars 22A and 22B are moved along the channel by a cam arrangement, not shown, or by any other suitable means that may be apparent to those skilled in the art. The wear plates 27, 28 between the slide bars 21A and 21B and the stripper plate 25 separate the stripper plate 25 from the slide bars 21A and 21B to prevent wear of the confronting surfaces of the slide bars 21A and 21B and stripper plate 25. However, the existence of this wear plate 27, 28 does not provide for a reliable application of clamping force between the slide bars 21A and 21B and the stripper plate 25 once the wear plate becomes worn.


A method for designing a die surface of a die, comprising generating a workpiece simulation-model corresponding to the workpiece, generating a target simulation-model corresponding to a target formed part, determining an initial die surface, which an initial numerical simulation predicts as forming the workpiece simulation-model into the target simulation-model, determining residual stresses resulting from forming the workpiece simulation-model into the target simulation-model, forming the workpiece into an actual formed part, generating a numerical representation of the actual formed part, generating an actual simulation-model, based on the residual stresses, matching the actual simulation-model and the target simulation-model, based on deviations between the matched target simulation-model and actual simulation-model, modifying the initial numerical simulation to provide a modified numerical simulation, and determining a corrected die surface, which the modified numerical simulation predicts as forming the workpiece simulation-model into the target simulation-model.

A large portion of manufacturing involves producing complex shapes from sheet metal and then joining these parts together to form a structure. These individual shapes are created mainly by a process called stamping. In the stamping process a flat sheet of metal is placed inside a die set typically consisting of male and female tools that, when closed together in a press, form the sheet metal to the desired shape. The die surfaces are designed using computer aided design (CAD) software and are then machined into the tool steel to make the dies.
The initial process of creating the die surface typically includes the use of Finite Element Analysis (FEA) software to predict how the metal will deform when the die is closed. This deformation includes effects like stretching, wrinkling and spring-back.
Spring-back is particularly challenging to consider when creating die surfaces because spring-back will cause a sheet metal part to change shape upon removal from the die. Accounting for spring-back requires that the die surface be designed such that the expected spring-back will deflect the part to the desired shape. Failure to adequately adjust for spring-back will cause problems during assembly and adversely affect the fit of parts.
Said FEA software is used to calculate the die surface shape needed to produce the desired final shape for the component. Due to the complex behaviour of the metal as it is being deformed when the die closes, FEA software is not able to predict the correct die face shape that is needed to actually arrive at the desired shape.
After the die is produced and during initial try out, parts are stamped and checked to see if they have the correct shape within manufacturing tolerances. If the part fails to meet specifications, then the die surface must be reworked. This process involves making changes to the die surface to correct regions that correspond to areas where the part is not meeting specifications. This is a mostly manual process performed by manufacturing engineers.
Typically, the parts formed in the tryout phase are measured using metrology equipment such as white light systems or laser scanners. This produces an electronic representation of the actual manufactured part. This representation is compared to the CAD model of the desired part and areas of deviation are measured and highlighted using colours. These deviations are then used to determine where and how much the die surface needs to be manually adjusted to compensate for the deviation.
Generally, the deviations between the actual formed part and the ideal part (target formed part) are used to make adjustments to the die surface design. Using experience, an engineer will tweak these deviations and adjust the die surfaces in the CAD software. This new die face design is then re-machined onto the existing die.
The die try outs are repeated and a small number of parts are formed. These are again compared to the desired shape in the CAD model and if parts do not meet specifications, the process of refining the die face is repeated again. The average number of iterations needed to produce a "good" die face design is around four but can be as many as ten or more. Once the die face is producing parts of acceptable quality, the die is then shipped to the stamping plant so it can be used to produce production parts.
While the current state of the art has been used successfully for many years, there are some limitations. The number of iterations needed to produce a good die face is undefined and makes planning difficult. Each time the die face needs to be modified, it takes around four weeks. This adds significant cost and effort to producing a die and can delay the launch of a product.
The computation of the new die face is a manual process based on experience. There is some trial and error involved and often the new die face does not correct all the problems of the prior one. The need for highly skilled engineers is also a limiting factor since it takes many years of experience to become expert in this process.
The use of an FE-analysis to help design the die face has improved initial die face quality but it is not able to fully account for the behaviour of the metal as it deforms when the die closes. The behaviour of newer materials such as high strength steel and aluminium are even more difficult to predict and result in substantially longer periods of time to iterate to an acceptable quality.


A light emitting diode (LED) display device comprises a substrate and a plurality of walls disposed on the substrate, the plurality of walls forming a cavity, the cavity being filled with an encapsulant not including fluorescent material. An LED is disposed on a first portion of the substrate within the cavity. An electrical connection exists between the LED and a second portion of the substrate, and a fluorescent material overlay is located at a top end of the cavity. The LED display device alternatively includes a plurality of LEDs, wherein each LED is disposed within a separate cavity.

Light emitting diode display devices are useful for a variety of display applications. Known display devices use an LED to excite a wavelength or color converting material, such as a fluorescent or luminescent material, and then combine the emission of the fluorescent or luminescent material with the unconverted first emission from the LED. However, while these known LED display devices perform well with a single-LED device, known multi-LED devices have difficulty maintaining color consistency. Accordingly, there remains a need for a device that addresses existing shortcomings relating to multiple-LED displays.

Avago Technologies ECBU IP (Singapore) Pte. Ltd


According to one embodiment, a lower order modulator is provided using a number of higher order modulators. According to another embodiment, a signal having a lower order spreading factor is generated using circuitry for generating a number of signals with a higher order spreading factor.

1. Field of the Invention
The present invention relates to communication, and more particularly, a method and apparatus for modulating and spreading communication signals.
2. Description of Related Art
Digital communication relies on numerous different, albeit related, forms of digital modulation such as phase shift keying (PSK), bi-phase shift keying (BPSK), quadrature phase shift keying (QPSK or 4-PSK), and quadrature amplitude modulation (QAM).
BPSK will be described with reference to FIG. 1. As shown, the magnitude of a reference carrier is constant, and to transmit either a 0 or a 1, the phase thereof is "keyed" or switched between 0° and 180°. A receiver then decides whether a 0 or a 1 was transmitted based on the phase of the received carrier, and generates the original data stream. With this simple scheme, one bit of information is transmitted with each state or symbol, so that the carrier phase is keyed at the data rate. FIG. 1 also illustrates the constellation for BPSK. As shown, the BPSK constellation diagram includes two points in the I-Q plane where I stands for in-phase (i.e., phase reference) and Q stands for quadrature (i.e., 90° out-of-phase). The two points in the BPSK constellation diagram represent the position of the signal at the "timing instance". The timing instance is when the receiver interprets the signal. The signal can only be at one position at a time, but the constellation can be thought of as having persistence so that all of the proper states appear. Constellation diagrams such as in FIG. 1 typically do not show the transition between states and it should be noted that this transition does take a finite time. But for clarity, the transitions are not shown otherwise traces connecting the two states would clutter the diagram. Furthermore, instead of being located on the I-axis, the constellation points could, for example, lie on the Q-axis.
FIG. 2 illustrates the constellation diagram for QPSK. As shown, four different states exist in the QPSK diagram at, for example, phase values of 45°, 135°, 225°, and 315°. As further shown, each state corresponds to a symbol representing two bits. Because the data is taken two bits at a time to form a symbol, the symbol rate is half the bit rate. As a result, QPSK requires half the band width of BPSK for the same bit rate.
FIG. 3 illustrates the constellation for 16-QAM (quadrature amplitude modulation). In addition to modulating the phase, the amplitude of the signal is also modulated to create four distinct constellation points within each quadrant of the I-Q plane. As shown, in 16-QAM, one symbol represents four bits of data.
FIG. 4 illustrates a prior art architecture for spreading and modulating data for transmission. As shown, a serial-to-parallel converter 10 converts the serial data to parallel. A modulation mapper 15 then maps the parallel data to respective symbols in the I-Q plane. For example, the modulation mapper 15 may map one type of channel according to QPSK and a different type of channel according to 16 QAM. For the example of QPSK, the serial-to parallel converter 1-10 converts serial data into respective pairs of parallel data. The modulation mapper 15, may map the binary value of "0" to the real value of +1, and the binary value of "1" to the real value of −1.
However, the modulation mapper 15 also receives I and Q DTX control signals DTXI and DTXQ. As is known, DTX stands for discontinued transmission (i.e., no transmission). Accordingly, if the I DTX control signal DTXI is asserted (e.g., DTXI is 0), the modulation mapper 15 outputs the real value of 0 as the I signal. Likewise, if the Q DTX control signal DTXQ is asserted (DTXQ is 0), the modulation mapper 15 outputs the real value of 0 as the Q signal. If the I DTX control signal DTXI and/or the Q DTX control signal DTXQ are not asserted (e.g., DTXI and/or DTIXQ is 1), then the modulation mapper 15 outputs the I and/or Q signals based on the received parallel data. As is known, instead of having separate DTX control signals for the I signal and the Q signal, a single DTX control signal may be used.
Next, the I and Q signals output from the modulation mapper 15 undergo spreading by a spreading unit 80. The spreading unit 80 includes a channelization operation and a scrambling operation. In the channelization operation, the I and Q data are multiplied with a channelization code Cch,SF,m by respective multipliers 20 and 25. Here, ch indicates the code C is a channelization code, SF is the spreading factor (described below) and m is the code number (also described below). The channelization operation transforms each data symbol into a number of chips, thus increasing the bandwidth of the signal. The number of chips per data symbol is called the spreading factor (SF).
Channelization codes may be Orthogonal Variable Spreading Factor (OVSF) codes that preserve orthogonality between different signals. The OVSF codes may be defined using the code tree of FIG. 5. As shown, the channelization codes are uniquely described as Cch,SF,m, where SF is the spreading factor of the code and m is the code number 0<=m<=SF−1. Namely, each code tree defines channelization codes of length SF, corresponding to a spreading factor of SF as shown in FIG. 5, and each channelization code of spreading factor SF may have SF code patterns uniquely identified by the code number m.
After channelization, the Q signal is shifted 90 degrees from the I signal by the multiplier 30, and a summer 35 sums the I and Q signals. As a result, the summation signal includes a total of eight chips for the pair of parallel input bits—four chips on the I signal portion and four chips on the Q signal portion. A multiplier 40 scrambles the summation signal output by the summer 35 by multiplying the summation signal with a scrambling code S. Namely, the sequence of complex valued chips are scrambled (complex chip-wise multiplication) by a complex-valued scrambling code S.
The scrambled summation signal is then modulated by a modulation unit 90. The modulation unit 90 includes a splitter 45 that splits the scrambled summation signal into real and imaginary parts. Respective pulse shapers 50 and 55 pulse shape the real and imaginary signals, respectively. Modulation is completed by mixing the real signal with a cos (wt) signal at multiplier 60 and the imaginary signal with a −sin (wt) signal at multiplier 65. A summer 70 sums the modulated signals to produce a signal for transmission.
Conventionally, the channelization, scrambling and modulation operations in the architecture of FIG. 4 are implemented in an application specific integrated circuit (ASIC). However, most third generation wireless communication standards create significant challenges in designing and developing architectures for baseband processing as described above with respect to FIG. 4. Add to this the fact that most of these standards are evolutionary, and it will be appreciated that creating such architectures is like hitting a moving target.

Method and apparatus for spreading and modulating communication signals