A splittable optical-fiber ribbon product that includes at least two sub-unit ribbons each having a plurality of optical fibers encapsulated in a matrix material. The sub-units are disposed adjacent to one another, and are attached to one another by an adhesion matrix material which does not fully encapsulate both of the sub-units.

1. Field of the Invention
The present invention is directed to splittable optical-fiber ribbon products and, more particularly, to optical-fiber ribbon products containing a plurality of sub-unit ribbons that may be separated into fully functional, independent optical-fiber ribbons.
2. Related Art
In the related art, sub-unit ribbons include a plurality of optical fibers encapsulated in a matrix material. A plurality of sub-unit ribbons are then fully encapsulated together to form a splittable optical-fiber ribbon product. Although any number of sub-unit ribbons may be encapsulated together, only two sub-unit ribbons are shown in FIG. 6. As shown in FIG. 6, a first subunit ribbon 10xe2x80x2 includes a plurality of optical fibers 1xe2x80x2 which are encapsulated by matrix material 2xe2x80x2. Similarly, a second sub-unit ribbon 20xe2x80x2 includes a plurality of optical fibers 1xe2x80x2 which are encapsulated by matrix material 2xe2x80x2. The first and second sub-unit ribbons 10xe2x80x2, 20xe2x80x2 are then fully encapsulated by encapsulation material 30xe2x80x2 to form a splittable optical-fiber ribbon product.
A continuing problem in the development of optical-fiber cables is that of providing a high fiber count in a small cable volume in an effort to reduce costs. The related art splittable optical-fiber ribbon product suffers disadvantages in this regard. First, the encapsulation material 30xe2x80x2 increases the width and thickness of the splittable optical-fiber ribbon product, thereby allowing a limited number of optical fibers 1xe2x80x2 to occupy a given volume. The width of the splittable optical-fiber ribbon product is the widths w1 and w2 of the first and second sub-unit ribbons 10xe2x80x2 and 20xe2x80x2, plus twice a hinge thickness th of encapsulation material 30xe2x80x2, which hinge thickness th exists on each side. Therefore, the width of the splittable optical-fiber ribbon product is increased by at least twice the hinge thickness th over the width of an optical-fiber ribbon made without sub-units and having the same number of fibers as the two subunits 10xe2x80x2 and 20xe2x80x2 together. Similarly, the encapsulation material 30xe2x80x2 is present on the top and bottom of the sub-unit ribbons 10xe2x80x2, 20xe2x80x2 as an overcoat having thickness to. Therefore, the thickness of the splittable optical-fiber ribbon product is thicker than either sub-unit by an amount that is twice the overcoat thickness to.
Further, the individual sub-units may be thicker and wider after being separated or split from the splittable ribbon than before they were joined together. Therefore, the remaining matrix material on the separated sub-units must be removed, which causes additional time delays when it is desired to use the sub-units as individual ribbons, as in connectors and other equipment, for example, after they are separated from the splittable optical-fiber ribbon product.
This increased width and thickness results in a lower packing density, i.e., a smaller fiber count within a particular volume for the splittable optical-fiber ribbon product as well as for the individual sub-units after they are split from the ribbon product.
In order to increase packing density, one related art solution involves using the encapsulation material to provide hinge coverage in the splittable optical-fiber ribbon product. That is, in this type of related art product, the individual sub-units do not have a matrix material which completely encapsulates the optical fibers. Instead, the optical-fibers are completely encapsulated only after the encapsulation material is applied. This arrangement thus attempts to increase packing density by eliminating the sub-units"" hinge thicknesses. When the sub-units are split, however, there is a distinct danger of having one of the fibers on either end of the sub-unit break out of the sub-unit package. This danger is especially acute on the end of the sub-unit that was previously adhered to another sub-unit because the sub-unit hinge is too thin to have the strength necessary to withstand the forces involved in the process of fracturing the encapsulation material that binds it to the adjacent sub-unit.
Another problem related to fully encapsulating the sub-unit ribbons is high cost in both materials and production of splittable optical-fiber ribbon products. That is, the encapsulation material 30xe2x80x2 can be quite expensive and, therefore, the more that is used, the more expensive the end product becomes. Further, the encapsulation material is typically cured using ultra-violet (UV) or other radiation. And the amount of energy required to cure the encapsulation material 30xe2x80x2 is proportional to the amount of material used.
Yet another problem in the optical-fiber industry is that of easily and quickly accessing the optical fibers within a splittable optical-fiber ribbon product. That is, for installation, service and maintenance purposes, it often becomes necessary to perform splicing and termination operations on individual optical-fibers within a splittable optical-fiber ribbon product. In order to access the individual optical-fibers, a peeling process is typically used. The peeling process must leave the optical fibers with their individual coatingsxe2x80x94including color coatingsxe2x80x94intact, yet peel away all of the sub-unit""s matrix material that binds them together. The sub-units of splittable ribbon products are easily split away from the combined optical-fiber ribbon product to facilitate access in the field. However, difficulty arises in that both an encapsulation material and a sub-unit matrix material must then be peeled off in order to access individual fibers. This situation will be described with reference to FIGS. 7 and 8.
FIG. 7 shows a first sub-unit ribbon 10xe2x80x2 after it has been split apart from the combined optical-fiber ribbon product shown in FIG. 6. As shown in FIG. 7, the sub-unit 10xe2x80x2 and the optical fibers 1xe2x80x2 are still encapsulated within encapsulation material 30xe2x80x2 as well as within matrix material 2xe2x80x2. Therefore, a two-step peeling process often must be performed to access the optical fibers 1xe2x80x2. That is, a first peeling process performed on the split-off sub-unit 10xe2x80x2 shown in FIG. 7 typically results only in removal of the encapsulation material 30xe2x80x2 leaving the sub-unit 10xe2x80x2 as shown in FIG. 8. A second peeling process must then be performed on the split-off sub-unit 10xe2x80x2 as shown in FIG. 8 to remove the matrix material 2xe2x80x2 so that the optical-fibers 1xe2x80x2 can be accessed.
Performing two peeling processes to access the optical fibers 1xe2x80x2 adds to installation time for workers in the field who are using such ribbons. When applied to high fiber-count installations, this added installation time can become quite sizable.
It is an object of the present invention to overcome the drawbacks of the related art. More particularly, it is an object of the present invention to provide a lower cost splittable optical-fiber ribbon product than that available in the related art, and one which also reduces external dimensions in order to increase its packing density, i.e., the space required to pack a stack of ribbons in a cable or tube. Reducing external dimensions reduces cost and increases packing density, thereby allowing a high fiber count to be provided in a small cable volume.
It is another object of the present invention to reduce the risk of fiber breakout in splittable optical-fiber ribbon products.
It is a further object of the invention to provide a splittable optical-fiber ribbon product in which individual optical fibers can be accessed easily and quickly. More particularly, it is an object of the present invention to provide a splittable optical-fiber ribbon product whose optical fibers can be accessed with only one peeling process, thereby reducing installation time in the field.
The present invention achieves the above and other objects and advantages by not fully encapsulating a splittable optical-fiber ribbon product""s sub-unit ribbons. Instead, adhesion matrix material, bonding material, or adhesive is applied only to the area in the gap between sub-units of a splittable optical-fiber ribbon product, and the sub-units themselves include a matrix material which encapsulates the individual optical fibers. The adhesion properties of the adhesion matrix material are such that when cured, it adheres well to all of the sub-units and, thus, effectively creates one ribbon. It is important to emphasize that the bond between the adhesion matrix material and the sub-unit matrix material must be sufficiently strong so that outward normal forces applied to the external surface of the adhesion matrix material are transferred to the sub-unit matrix material. If this bond is sufficiently stronger than the similar bond existing between the sub-unit ribbon matrix and the individual fibers"" secondary coating, then the outward normal forces applied by the peeling process will cause a break in to occur at the interface between the sub-unit matrix and the individual fibers, rather than between the sub-unit matrix and the adhesion matrix material. Additionally, the adhesion matrix material is sufficiently brittle so that the final product can easily be split into respective sub-units, yet is sufficiently tough that the finished product does not break apart during the cabling process. The combination of the edge-bondedxe2x80x94not fully encapsulatedxe2x80x94design and the choice of adhesion matrix material for optimized adhesion properties allows for the achievement of the desired final ribbon properties. This is because normal manufacturing process variations may allow for the adhesion matrix material to be applied in locations other than in the interstitial gap between sub-units. For example, if the adhesion matrix material is present on the top surface of ribbon, due to normal production variations, the transfer of normal forces on this adhesion matrix layer to the sub-unit matrix layer will improve the peel performance and allow the one step peel process to be accomplished.
The adhesion matrix material in the present invention may be any UV or other radiation-curable acrylate, as is typically used in the optical-fiber industry. Examples of the adhesion matrix material according to the present invention are DSM-C9-32 available from DSM Desotech Incorporated, Borden 255 UV-curable acrylate, or any minor variation of these or similar materials. It is understood that the adhesion matrix material must be of similar composition as the sub-unit matrix material, however, the minor variations possible might include formulation changes for promoting adhesion, for altering the brittleness, or any other material property variation deemed desirable.
Although it is preferable to use an adhesion matrix material which is the same as that of the sub-unit matrix material, different materials may by used for each. However, the adhesion matrix material must be sufficiently similar to the sub-unit matrix material so that it forms a strong enough bond to hold the sub-units together during processing and handling. Further, the adhesion matrix material may be a color different from that of the sub-unit ribbons"" matrix material so that the sub-units can be easily identified and, therefore, easily split-off from the splittable optical-fiber ribbon product.
A negligible thickness of the adhesion matrix material may, or may not, exist across the external surfaces of the sub-unit, as on the top, bottom and hinge ends of the sub-units. However, the only appreciable buildup of this material is in the interstitial gap between the sub-units. The sub-units themselves can, therefore, be manufactured such that their dimensions are identical, or nearly identical, to the dimensions of any standard ribbon of similar fiber count that is manufactured for independent use, i.e., a ribbon that is not of a splittable-type.
Because a splittable optical-fiber ribbon product""s sub-unit ribbons are not fully encapsulated by encapsulation material, the splittable optical-fiber ribbon product of the present invention allows a tighter packing density than a fully encapsulated ribbon. This means that the same number of ribbons, with identical fiber counts, can be packaged in a tube or cable having a smaller diameter than that made with the conventional splittable optical-fiber ribbon products. Further, the sub-unit ribbons have a tighter packing density after they have been separated from the splittable optical-fiber ribbon product.
Additionally, using sub-units that fully encapsulate their optical fibers, sub-unit geometrical independence is maintained and the adhesion matrix material is used merely to adhere sub-units together. Such allows for a reduced risk of having end fibers break out during or after a sub-unit has been split apart from the splittable optical-fiber ribbon product. Such also allows the sub unit ribbons easily to be used in standard connectors or other apparatuses designed for independent-use ribbons, i.e., ones which are not of a splittable-type and, therefore, do not have the additional thicknesses th and to.
Further, because a splittable optical-fiber ribbon product""s sub-unit ribbons are not fully encapsulated by encapsulation material, a substantially smaller volume of a rather expensive material is required, and the sub-units are more easily separated into independent, fully functioning, sub-units when it is desired to do so.
Moreover, according to the present invention, because a splittable optical-fiber ribbon product""s sub-unit ribbons are not fully encapsulated by encapsulation material, a peeling process to access individual fibers is simplified and shortened. That is, only one step is necessary to peel the splittable optical-fiber ribbon product of the present invention, thereby reducing installation, service and maintenance time.

Edge-bonded splittable optical-fiber ribbon


A semiconductor device comprising a high breakdown voltage transistor and a low breakdown voltage transistor. The semiconductor device comprises a support substrate, an insulating layer formed on the support substrate, a high breakdown voltage transistor, a low breakdown voltage transistor, wherein the high breakdown voltage transistor is adjacent to a first isolation region having a depth that reaches the insulating layer, and the low breakdown voltage transistor is adjacent to a second isolation region having a depth that does not reach the insulating layer.

1. Field of the Invention
The present invention relates to a semiconductor device equipped with MOS (Metal Oxide Semiconductor) transistors with different drain breakdown voltages that are provided on the same SOI (Silicon On Insulator) substrate.
2. Description of the Related Art
In recent years, mobile electronic appliances have been made smaller and lighter, making it essential to miniaturize ICs that are mounted in such electronic appliances. In particular, for an electronic appliance on which a liquid crystal display device is mounted, there are strong demands to reduce the chip area of a driver IC, which drives the liquid crystal display device, by mounting transistors with a low breakdown voltage for low voltage operations and transistors with a high breakdown voltage for high voltage operations on a same substrate (i.e., in the same chip).
However, to achieve a sufficiently high breakdown voltage, it is not possible to reduce the area of a transistor forming region for high breakdown voltage transistors. Accordingly, no matter how much low breakdown voltage transistors are miniaturized, it has not been possible to make large reductions in the chip area of a driver IC.
When high breakdown voltage transistors and low breakdown voltage transistors are formed on the same SOI substrate, it is necessary to change the structures of the transistors to make the transistors suitable for an SOI substrate so as to avoid the substrate floating effect and the like that are characteristic to SOI substrates. Therefore, it is not possible to apply design resources that have been produced for the case where transistors are formed on a bulk silicon substrate.

Semiconductor device and method of manufacturing the same


An air conditioner 1 includes: an outdoor heat exchanger 14; an outdoor fan 12 for blowing air to the outdoor heat exchanger; an outdoor fan motor 20 that drives the outdoor fan; an outdoor fan inverter 21 that drives the outdoor fan motor; and a control unit 31 that generates a rotation-speed command voltage for controlling the rotation number of the outdoor fan motor. In addition, the control unit starts a defrost operation of the outdoor heat exchanger, based on the rotation-speed command voltage. In this manner, it is possible to achieve an outdoor device of an air conditioner in which there is no need to provide a current detecting sensor, and it is possible to detect frost formation over the heat exchanger during a heating operation and to perform a defrost operation at low costs.

As an air conditioner in the related art in which frost formation on an outdoor heat exchanger of an outdoor device is detected during a heating operation and defrost is performed, an air conditioner is disclosed in JP-A-60-144546 (PTL 1). PTL 1 discloses the air conditioner in which a current of an outdoor air blower (outdoor fan) that performs blowing of air to an outdoor heat exchanger is measured, thereby frost formation on the outdoor heat exchanger during a heating operation is detected, and a defrost operation is performed. In other words, such technology, in which an increase in the current of an outdoor fan motor is detected, thereby frost formation on a heat exchanger is estimated, and the defrost operation is performed, has been known.

HITACHI-JOHNSON CONTROLS AIR CONDITIONING, INC.


A system and method for determining the load present in a material handling system is disclosed. A commissioning routine executing on a motor drive controls operation of a hoisting motor with a known load present. The commissioning routine stores values of current provided to the motor or torque generated by the motor at various operating speeds in memory on the motor drive. During subsequent runs of the motor drive, the value of the current/torque is monitored as a function of the speed of the motor and compared to the stored values. The resulting value of the load may be monitored and action taken if the value of the load exceeds the rated capacity of the material handling system. Optionally, the measured load may be displayed to an operator.

The subject matter disclosed herein relates to measuring the load in a material handling system. More specifically, the subject matter disclosed herein relates to a method and apparatus for measuring the load in a material handling system using a motor drive controlling operation of the hoist motor.
Material handling systems are widely used to lift heavy loads, weighing up to hundreds of tons. A typical material handling system includes at least one motor used to raise and lower the load and at least one additional motor to position the material handling system over the load to be moved. Common applications include manufacturing facilities, in which large components may be positioned for assembly and/or the final assembly may be moved for shipping. Further, material handling systems are often required to handle loads of varying sizes. It is known that electric motors are capable of producing rated torque up to rated speed. Therefore, it may be desirable to verify that the weight of the load the system is attempting to move is less than or equal to the rated capacity of the system, such that the operator may safely raise/lower and position the load.
It is known that this weight measurement may be performed by the addition of an external weighing device, such as a load cell. However, external weighing devices have not been realized without certain disadvantages. External weighing devices add expense in both material and commissioning costs. The load cell is typically mounted to a mechanical component of the material handling system that is subject to a degree of strain or deflection as a result of lifting the load. Consequently, the load cell may need to be mounted on the hook or another movable member of the material handling system. The feedback signal from the load cell must then be wired or wirelessly communicated to a controller. The feedback signal may also need calibration to the load.
As is understood in the art, weighing devices measure forces applied to the device. The force applied as a result of gravity acting on the load corresponds to the weight of the object; however, in a material handling system, other forces are similarly applied to the weighing device. For example, the torque required to accelerate a load when raising the load or to decelerate a load when lowering the load provides an additive force on the weighing device. Similarly, deceleration when raising or acceleration when lowering is assisted by gravity, resulting in a reduced weight being measured by the weighing device. In order to obtain an accurate measurement of the weight of the load, therefore, the motor either raises and suspends the load at zero speed or operates for a short period at a constant speed when measuring the load.
Other systems have been introduced to obtain a measurement of the load as a function of the current provided to the motor. However, these systems have similarly not been realized without certain disadvantages. Although the current provided to the motor is a function of the weight of the load, the current is also a function of the torque applied to the load. Therefore, the magnitude of the current also varies during acceleration or deceleration of the motor. Consequently, current measurement systems may also require the motor to either raise and suspend the load at zero speed or operate for a short period at a constant speed when measuring the load. As a result of the limitations on obtaining accurate measurements, systems that employ either a load cell or current measurement may perform an initial test of the weight of the load, but make no further checks as a load is raised or lowered.
However, in some applications, the weight of the load may vary during as the load is raised or lowered. In some instances, the variation in weight may be unexpected. For example, in the shipping industry, containers are loaded and unloaded between storage facilities, trucks, trains, and ships. The containers are often stacked several layers high and in close proximity to each other or to walls, for example, within a hold of a ship. As the container is raised or lowered, it may sway, for example, due to the wind, or the other containers may move, for example, as the deck of a ship moves. In either instance, the container may contact or become snagged on an adjacent container, causing a change in the weight of the load. In other instances, the variation in weight is part of the application requirements. For example, bulk materials such as sand or salt may require a bucket, or clam shell, attachment. The clam-shell is lowered in an open position and closed to scoop up a load of the bulk material. As the operator begins to raise the clam-shell, there may be some initial slack in the cable. The weight of the load may be significantly lower or even near zero during the period at which the load is measured. The load may, therefore, be initially determined as safe but may subsequently exceed the rated capacity of the material handling system.
Thus, it is desirable to provide a system configured to periodically monitor the weight of the load throughout a run without requiring external load measurement devices.

Method and apparatus for measuring a load in a material handling system


An artificial miniature landscape model includes a plurality of multi-colored LEDS, metallic conductor branches, electrically insulated conductors, heat shrink bushings, or insulation tubular plugs, or internally or externally threaded tubular connectors, a low voltage rectifier, base connectors, molded artifacts, and pots. A plurality of variable colored LEDS are affixed to a molded transparent resin structure of an artificial flower, fruit, bird, leaf or butterfly to exhibit a three dimensionally colored lighting effect. Further, connectors are provided for connection of electrical conductors that supply power to illuminate the LEDS and to operate electrical devices that accompany the miniature landscape model.

1. Field of the Invention
The present invention relates to an artificial miniature landscape model which is ornamented with three dimensionally variable colored LEDS.
2. Description of the Prior Art
The conventional illuminated decorative potted plant displays which can be bought from the markets are usually formed of a fixture containing an incandescent lamp. As it is well known that the incandescent lamp has several inherent disadvantages of a low efficiency, a short lifetime and a low light intensity, it is therefore not suitable for use where ample color variation and light intensity are required.
Besides, instead of the incandescent lamp, LEDS have been installed in the bottom cavity of a rotatable pot to illuminate the potted plant upwardly from the bottom. However, the bottom of the pot often interrupts transmission of the light beam of the LEDS, thereby considerably lowering the lighting effect.
In view of this, a light source has been introduced to the flower with an optical fiber conductor, but as the light source is a spot light affixed to the flower without being matched with the contour of the flower, there is a lack of a three dimensionally vivid and appealing display. For demonstration of an active feeling, the pot is rotated by a driving motor together with a color disc, thereby always causing inevitable noise from the rotating motor and shortening the durability of the light source.

Artificial miniature, landscape model with three dimensionally variable colored LEDS


The object of this invention is to provide a highly reliable penetrating type X-ray tube and a manufacturing method thereof, preventing interfacial exfoliation between a transmission window and a target film before it happens.

1. Field of the Invention
This invention relates to a X-ray tube such as a penetrating type X-ray tube, especially to an X-ray tube of this kind where exfoliation at the interface of a target film from which X rays generate, formed on the inner surface of an X-ray transmission window plate being a part of its evacuated envelope is prevented from occurring and to a manufacturing method thereof.
2. Description of the Related Art
An X-ray tube has a structure in which X rays are emanated by an electron beam collided with an anode target. The X-ray tube is used in various fields such as industrial use e.g. medical diagnosis, nondestructive testing or material analysis. Various kinds of X-ray tubes are in use according to these demands. Among them, there is a transmission emanating type X-ray tube that offers a minute focal spot, i.e. micro focus X-ray source.
One of utilization of the micro focus transmission emanating type X-ray tube is an X-ray fluoroscopic magnified image pickup device for semiconductor integrated circuit boards or other objects. As shown in FIG. 7, X-ray tube 12 is accommodated in device case 11 which shields X rays. Object 13 such as the semiconductor integrated circuit board is set at the position apart from X-ray focal point S of X-ray tube 12 by the distance La. Furthermore at the position apart from object 13 by the distance Lb, the sensor surface of X-ray area sensor such as an X-ray image tube or a solid state X-ray sensor is positioned facing thereto.
An operating voltage which is controlled from outside is to be supplied to X-ray tube 12 by means of power source 15 contained in case 11. An X-ray image signal derived from X-ray image signal output section 16 of X-ray area sensor 14 is transmitted to monitor 17 having a image processing device so as to display an X-ray fluoroscopic magnified image of object 13 on image display section 18.
Magnification M of an X-ray imaging of an object is represented approximately by M=(La+Lb)/La. Since both the distances are set to be La((Lb, the smaller the distance La becomes, the larger the magnification M increases. It is also self-evident that the smaller the size of focus S which is the origin of X rays in the X-ray tube is, the clear the X-ray fluoroscopic magnified image becomes.
Therefore, it is desirable that the focus S of the X-ray tube, i.e. the X-ray emanating target section should be located as close as possible to object 13, in order to make distance La as small as possible. For this purpose, utilization of a micro focus transmission emanating type X-ray tube in which an X-ray emanating target is at the utmost tip of the tube is suitable.
As shown in FIG. 8, such X-ray tube 12 has X-ray transmission window 22 permeable to X rays, provided vacuum-tightly at one of the tips of the metallic hollow cylinder of evacuated envelope 21. Transmission window 22 is usually made of a material highly permeable to X rays such as beryllium (Be). On the surface of the evacuated side of transmission window 22, anode target film 23 of tungsten (W) etc. is directly stuck, as the main part is shown magnified. Inside the glass portion of the other side of the evacuated envelope, cathode 24 emitting an electron beam is mounted and electron gun 25 comprising the cathode and a plurality of grid electrodes for an electron lens is accommodated.
In the above mentioned structure, electron beam e emitted out of the cathode and passing through electron lens 25 is designed to make point focus S at anode target film 23. Then, X rays generated at the anode target film are emanated out as they are, via transmission window 22. The emanated X rays represented by mark X are used for X-ray imaging.
The apparatus or the X-ray tube like this is disclosed, for example, in U.S. Pat. No. 5,077,771, Japanese Patents No. 2,713,860, No. 2,634,369, Japanese Patent Publication No. Hei/7-50594, Japanese Patent Disclosure No. Hei/9-171788, Japanese Utility Model Publication No. Shou/52-56778, and Japanese Utility Model Disclosure No. Shou/54-163885.
The optimum thickness of the tungsten film constituting the anode target of the transmission emanating type X-ray tube depends on the voltage supplied to the tube. For instance, in the case of industrial X-ray tubes, the voltage supplied to the X-ray tube is generally in the range from several tens kV to one hundred and several tens kV. In such a case, the optimum thickness of the tungsten film constituting the anode target is in the range from several xcexcm to ten and several xcexcm.
The structure where a tungsten film constituting the anode target is directly stuck to the inner surface of the beryllium X-ray transmission window is apt to generate an interfacial exfoliation between tungsten and beryllium, and to result in unstable state, under the influence of the remaining stress in the film generated while the tungsten film is being formed or of the difference of thermal expansion coefficient between tungsten and beryllium constituting the transmission window.
Especially, for a micro focus penetrating-type X-ray tube, the interfacial exfoliation is liable to take place at the micro focus part, because an electron beam having, for example, a focus of substantially circular configuration of several tens xcexcm or less in diameter impinges on the tungsten film. If the interfacial exfoliation takes place, it is thought that melting of the tungsten film or spattering of exfoliated material caused by local irradiation of the electron beam may result in serious damage of the X-ray tube.
The object of this invention is to solve the above mentioned shortcomings and to provide a highly reliable penetrating type X-ray tube and a manufacturing method thereof, preventing interfacial exfoliation between a transmission window and a target film before it happens.
The penetrating type X-ray tube according to the present invention has a X-ray transmission window plate of beryllium stuck vacuum-tightly to a portion of an evacuated envelope, a target film of tungsten or of an alloy mainly constituted of tungsten which is provided on the evacuated side of the window plate and emanates X rays, and at least one intermediate film of at least one metal element such as copper or of a material principally constituted of this metal element intervening closely between the window plate and the target film.
The manufacturing method according to the present invention is characterized in that at least one intermediate film of at least one metal element selected from copper, chromium, iron, nickel, etc. or of a material principally constituted of this metal element and an X-ray generating target film are formed on the inner surface of the X-ray transmission window of beryllium and on the intermediate film respectively by a physical vapor deposition method such as spattering.

Penetrating type X-ray tube and manufacturing method thereof

Abstract: This invention is characterized in that at least one intermediate film 39 of at least one metal element or an alloy thereof selected from a group of copper, chromium, iron, nickel, etc. between x-ray penetrating window plate 37 of beryllium stuck vacuum-tightly to a portion of evacuated envelope 33, and target film 40 of tungsten which is provided on the evacuated side of the window plate and emanates X rays is formed by a physical method such as spattering.


A system and method for extracting a biological fluid from an organism and continuously monitoring its characteristics. The system includes a tissue interface device suitable for positioning on or about the surface of the biological membrane of the organism and a monitor and control unit coupled to the tissue interface device. The tissue interface device includes a sensor positioned in a flow path of the fluid for continuously sensing a characteristic of the biological fluid as it flows out from the one or more artificial openings formed in the biological membrane. The sensor generates a sensor signal representative thereof. The monitor and control unit electrically or optically reads the sensor to obtain a measurement of a characteristic, such as concentration of a particular analyte, of the biological fluid on a continuous basis.

The present invention relates to analyte monitoring systems, and more particularly to a continuous analyte monitoring system wherein fluid is extracted from an organism and monitored outside of the organism to obtain a measurement of a characteristic of the fluid, such as analyte measurement.
Monitoring systems that sample and measure characteristics of fluids from an organism, such as a human, are well known. Many of these systems involve implanting sensors and related devices into the organism (such as under the skin) in order to obtain samples and make measurements of those samples. Even for short term implants, it has been shown that within the first several hours after implantation a rapid deposition of fibroblasts, macrophage plaques, fibrogen growth and other natural physiological encapsulation processes surround the implant and thereby impair, restrict, and modify, in a dynamic fashion, the free flow of the analytes of interest into the active sensor region of the implanted device. The typical method for compensating for these encapsulation effects involves calibrating the sensor against a conventional in vitro analysis method several times over the first few days. Further, once implanted, the sensors must be frequently calibrated, resulting in trauma to the implanted site and additional finger sticks to obtain the blood for calibration. The need to conduct multiple calibrations largely eliminates much of the advantages for many of the implanted continuous monitoring systems.
An additional restriction on the performance of the implantable sensors is that the internal environment is typically low in oxygen. This can limit the performance of many classes of reactive bio-sensors that invoke an analyte specific reaction which requires oxygen. One solution employed in some of the implants being developed is to use a restrictive diffusion membrane which limits the proportional amount of the analyte of interest which is allowed to reach the assay element, thereby extending the useable life of the implanted sensor in the oxygen lean internal environment. This compromise solution can have detrimental effects on response time, linearity of response to serum level changes in the analyte, and basic assay signal-to-noise ratio (SNR)

System and method for continuous analyte monitoring


A method for producing nanoparticles on a substrate using a metal precursor in an ionic liquid and microwave heating is described. The composite compositions are useful as catalysts for chemical reactions, fuel cell, supercapacitor and battery components, and the like.

(1) Field of the Invention
The present invention relates to a method for producing metal nanoparticles on a solid surface of a substrate. In particular, the present invention relates to nanoparticles of a metal deposited on nanoparticles comprising a carbon or graphite in various forms such as carbon black, fibers and nanotubes, for instance.
(2) Description of the Related Art
U.S. Pat. No. 6,596,130 to Westman generally describes a process for microwave associated chemical transformation of organic compounds using ionic liquids (IL). This reference is incorporated herein in its entirety, particularly in reference to the ionic liquids. Microwave reactors are well known to those skilled in the art.

Compositions of nanoparticles on solid surfaces

BOARD OF TRUSTEES OF MICHIGAN STATE UNIVERSITY


A chemiluminiscent, disposable laryngoscope is disclosed. The device comprises a handle portion with an end and a blade portion which is integrally formed on the end of the handle portion. The blade points away from the handle portion substantially perpendicularly. Inside the blade there is disposed a container which, upon activation, provides chemiluminiscent light. The blade is, at least in portions thereof, formed of translucent material. The unit is selfcontained, self-lighting and disposable as a whole.

1. Field of the Invention
The invention relates to a disposable laryngoscope, and more particularly to a self-lighting unit.
Laryngoscopes are medical devices which are used in the examination of the rear oral cavity and the larynx. The device is often used by anaesthesiologists during the insertion of an endotracheal tube in a patient's larynx.
2. Description of the Related Art
Generally, laryngoscopes are used to hold down the tongue, so as to expose and make visible the laryngeal area of the patient. Most modern devices of this kind are comprised of a handle portion and a blade portion affixed thereto. Means for lighting the laryngeal area are incorporated in the device. In many instances the blade is disposable, i.e. the handle is used again after the blade portion has been replaced.
Many such devices have been proposed through the years. U.S. Pat. No. 3,598,113 to Moore provides a handle with a light source incorporated therein. The light energy is transferred through the disposable blade by means of a strand of optical fibers. The light unit, which includes a battery, a lamp and a switch, is retained, while the blade and handle portions are disposed of after use.
U.S. Pat. No. 4,570,614 to Baumann is representative of a type of laryngoscope with a disposable blade portion. The handle portion incorporates a battery pack and a light source. A light conductor guides the light through the blade towards a distal region thereof.
All of the prior art devices have in common that at least one part or another is frequently reused. Especially in light of recent developments and the spreading of AIDS and other transferrable diseases, the prior art devices are seen to be potential transfer carriers.


A power amplifier module includes a first phase shifter, a second phase shifter, and an electromagnetic shield. The first phase shifter includes a first transmission line assembly to shift a first amplified signal by a first phase angle. The second phase shifter includes a second transmission line assembly to shift a second amplified signal by a second phase angle. The electromagnetic shield is arranged to shield the first transmission line assembly from the second transmission line assembly. The power amplifier module may have, for example, Doherty amplifier configuration.

Power amplifiers are used in a variety of applications. In a wireless communication system, a power amplifier generates amplified radio frequency signals to an antenna for communicating information such as calls and data. In terms of performance, a power amplifier may operate at maximum power efficiency when transmitting at or near saturated power. However, power efficiency tends to worsen as output power decreases.
Recently, the Doherty amplifier architecture has been the focus of attention to support wireless communications. A Doherty power amplifier may use strategies that differ, for example, based on phase difference between carrier (or "main") and peaking power amplifiers. One type of Doherty power amplifier uses a 90/0 strategy, where a 90 degree phase shift is applied to the peaking signal prior to amplification along the peaking amplifier path, and a corresponding 90 degree phase shift and impedance inversion is applied to the carrier signal after amplification along the carrier amplifier path and before the amplified carrier and peaking signals are combined together in phase at a combining node. However, a 90/0Doherty power amplifier has narrowband performance and therefore is unable to satisfy the requirements of many applications.
Another type of Doherty power amplifier uses a 90/180 strategy, which provides broader RF bandwidth. However, a 90/180 Doherty power amplifier as currently designed is unsuitable for use in the limited space available in a power amplifier module. Adding lumped components may help save space in certain circumstances to achieve 90/180 Doherty power amplifier, but not without a tradeoff in efficiency.

Power amplifier with shielded transmission lines


A selective call receiver (106) receives a radio frequency signal having digital signals contained within symbols. The signal demodulated by the receiver (804) comprises a substantially constant DC offset voltage and an AC voltage (1810) indicative of the information contained within the symbols. A threshold level extraction circuit (808) which extracts the offset voltage is synchronously controlled (1840) providing for sampling of the received signal by the threshold level extraction circuit in substantially the center of each symbol.

Radio frequency signals received by portable receivers such as pagers, are mixed down to an intermediate frequency and demodulated. The demodulated signal comprises a substantially constant offset voltage with information modulated thereon. The offset voltage is a function of the radio frequency carrier offset, the frequency tolerance of the receiver's local oscillator, and individual characteristics of the demodulator circuit. These characteristics vary from one receiver to another, as well as with the ambient temperature and battery voltage. Thus the offset voltage varies over time and must be determined periodically in order to extract the information modulated thereon. The information is extracted and digitized by comparing the offset voltage to the output of the demodulator.
Extracting the offset voltage (otherwise referred to as a threshold voltage) has been a subject of numerous inventions. However, as digital signalling protocols for portable devices such as pagers move into both higher symbol rates and multi-level symbol signalling systems, the problems in this area are compounded. In simulcast environments (as well as Gausian environments), the rapidly changing signals may combine with noise in the receiver's IF to produce noise spikes during the transitions between symbols. These noise spikes interfere with the acquisition of the offset voltage. Thus it is desirable to determine the location of the noise spikes and block their interference with the acquisition of the offset voltage.

Synchronized offset extraction in a data receiver


A system and method for efficiently and effectively simulating hardware-in-the-loop testing of a wireless communications network. The system and method employs an optical matrix-vector multiplier (MVM) for performing optical signal processing to simulate radio frequency (RF) signal propagation characteristics in a mobile wireless communications network. Specifically, the system and method employs an optical modulator, which is adapted to modulate optical energy with signal energy, such as radio frequency (RF) signal energy, propagating from a first group of transceivers of the network to form a vector of optical signals. The optical matrix-vector multiplier (MVM) receives the vector of optical signals, and has a matrix of optical channel weights which are modifiable in accordance with desired parameters to represent at least on parameter of the wireless network. The optical MVM is further adapted to output signals based on the received vector of optical signals and the optical channel weights. The system and method further employs a detector device, adapted to detect the output signals and to provide the output signals as an output vector of signals to a second group of transceivers of the network.

1. Field of the Invention
The present invention relates to a system and method for providing simulated hardware-in-the-loop testing of a wireless communications network. More particularly, the present invention relates to a system and method which employs an optical matrix-vector multiplier for performing optical signal processing to simulate radio frequency (RF) signal propagation characteristics in a mobile wireless communications network.
2. Description of the Related Art
In recent years, a type of mobile communications network known as an "ad-hoc" network has been developed for use by the military. In this type of network, each user terminal is capable of operating as a base station or router for the other user terminals, thus eliminating the need for a fixed infrastructure of base stations. Details of an ad-hoc network are set forth in U.S. Pat. No. 5,943,322 to Mayor, the entire content of which is incorporated herein by reference.
More sophisticated ad-hoc networks are also being developed which, in addition to enabling user terminals to communicate with each other as in a conventional ad-hoc network, provide intelligent access points (IAPs) that enable the user terminals to access a fixed network and thus communicate with other user terminals, such as those on the public switched telephone network (PSTN), and on other networks such as the Internet. Details of these types of ad-hoc networks are described in U.S. patent application Ser. No. 09/897,790 entitled "Ad Hoc Peer-to-Peer Mobile Radio Access System Interfaced to the PSTN and Cellular Networks", filed on Jun. 29, 2001, and in U.S. patent application Ser. No. 09/815,157 entitled "Time Division Protocol for an Ad-Hoc, Peer-to-Peer Radio Network Having Coordinating Channel Access to Shared Parallel Data Channels with Separate Reservation Channel", filed on Mar. 22, 2001, the entire content of both of said patent applications being incorporated herein by reference.
To test a wireless network, such as an ad-hoc wireless network as described above, with modem radio hardware-in-the-loop, it is desirable to provide a testbed that would simulate a deployed network of transceivers in an automated and repeatable fashion. The design and deployment of many kinds of communication networks including cellular, cable, satellite, ad-hoc, and others can benefit from a test capability of this kind. Also, the specific ability to exercise a network of modem or radio transceivers in the presence of a controlled and scripted RF simulation environment would be invaluable.
A conventional method of incorporating RF signal propagation effects and transceiver mobility into the testing of a network has typically involved the use of a small group of test personnel with mobile transceivers. In the case of point-to-point networks, RF switching matrices have been employed without the need for full fanout of the network nodes. However, for systems of greater connectivity, it is usually necessary to exclude the physical layer from network test.
An example of a system having this greater connectivity is an ad-hoc wireless network of the type discussed above. The ad-hoc wireless network comprises a plurality of combined router/IAP devices and subscriber radios, such as mobile user terminals, that are fully connected in the RF sense with a dynamic link attenuation for each path between radios that is under real-time control. Such attenuation models propagation path loss, fading, mobility-induced power changes, and the implementation of power control algorithms which govern adjustment of individual transmitter power levels. A brute force approach to simulating this scenario would involve connecting a population of radios together using a full fan out microwave switching matrix with digitally-controlled attenuation along each path. However, this is generally considered to be a prohibitively expensive technique, the cost of which would be further exacerbated by providing real-time control of path delay.
Accordingly, a need exists for a system and method capable of performing simulation testing on a communications network, such as an ad-hoc communications network, with minimal complexity and cost.

System and method for providing simulated hardware-in-the-loop testing of wireless communications networks


A head and facial protection system comprising a helmet and an attachable eye protection, said helmet comprising an inner and outer surface, a core between the inner and outer surfaces, a first and a second forehead mount, and a left and right post; wherein the eye protection secures to the first and second forehead mounts and the left and right posts to enable adjustment of the attachable eye protection.

Helmets have a long history of use in athletics as well as in motorsport and events where head trauma is possible. Many of these helmets have a single, fixed eye protection that is attached to the helmet to prevent eye injury. For example, in motocross, steel cages or rigid clear polycarbonate shields and visors are frequently secured to the helmet for protection. Similarly, in American football the facial cage protects the eyes with a rigid metal cage or clear polycarbonate material.
For many years no protection was used in ice hockey, but eventually helmets were included to protect from head trauma. Indeed, ice hockey is just one example of a sport adding head protection to reduce the occurrence of head trauma. However, even with the adoption of head protection, helmets vary greatly in their level of facial or eye protection, with some including full facial shields or cages while others include a smaller visor comprising a rigid metal or plastic cage or clear polycarbonate material. These cages or visors are mounted rigidly to the helmet to function as an extension of the helmet.
Another sport that adopted helmet protection over the past 30 years is the ski and snowboarding industry. Early on, skiers and riders recognized the need for head protection with the advent of terrain parks that included rails and obstacles, as falls were more prevalent and the surface unforgiving, resulting in significant injury. Finally, members of the general population recognized that helmets should be used for all terrain, as any fall included a significant risk of head injury. In ski applications, helmets frequently provide space for wear and use of preferred eyewear. Some individuals prefer to ski with traditional sunglasses, while others use sport specific goggles. Many helmets have included snaps or guides in the helmets to enable better placement of specific eyewear to ensure its proper fit for the user.


Pseudoephedrine hydrochloride extended-release tablets including a sustained release hydroxypropylmethylcellulose matrix and a microcrystalline cellulose disintegrant formed by a dry mixed, direct compression method.

The advantages of sustained release products are widely recognized in the art and are of extreme importance in the pharmaceutical field. Through the use of such products, orally administered medications can be delivered continuously at a uniform rate over a prolonged period of time so as to provide a stable, predetermined concentration of a drug in the bloodstream, without requiring close monitoring and frequent re-administration.
The sustained release character of such products is achieved by one of two methods: 1) providing a sustained release coating upon tablets or microspheres wherein slow release of the active occurs via either gradual permeation through or gradual breakdown of this coating or 2) providing a sustained release matrix, such as a fat, a wax, or a polymeric material intermixed with the active ingredient in the tablet itself. See, e.g., Manford Robinson, "Sustained Action Dosage Forms" in The Theory and Practice of Industrial Pharmacy, ch. 14 (L. Lachman et al., eds., 2d ed., 1976).
Such sustained release matrix formulations are typically prepared by methods involving pre-granulating the active ingredient together with the matrix material via a wet granulation, solvent granulation, shear-melt or roto-melt granulation, or a wet pre-adsorption technique. In these techniques, a liquid phase is used in order to uniformly mix and/or closely contact the ingredients together so as to provide an evenly distributed matrix in intimate association with the active ingredient. These formation processes help prevent creation of interspersed quick-release zones which would result in discontinuous dissolution of the tablet and thus cause bioconcentration spikes of active ingredient in the patient. They frequently also result in tablets of a relatively higher density than the dry mixed ones, thus allowing the use of tablets, for a given dose, that are smaller than those made by dry mixing for the same intended release rate.
However, these liquid phase methods require a multiplicity of steps and equipment for storage, handling, and dispensing of liquids, for drying, and/or for heating of the ingredients. When the liquid is water, its volume must be very carefully controlled so as to prevent any disintegrant in the formula from swelling. Also, water is incompatible with hygroscopic active ingredients. Yet, when the liquid is instead a volatile organic solvent, additional precautions must be taken to address the risks of fire, explosion, and worker exposure. Where a melt processing technique is used, heating presents a risk of inactivation of at least some of the active material and is incompatible for use with some active ingredients.
Thus, dry mixing has sometimes been used to form sustained release matrix tablets. This technique involves pre-mixing the matrix material with the active ingredient, without the use of added liquids or heat, so that only ambient humidity, temperature, and particle-to-particle surface interactions and/or static electrical attraction foster adherence, if any, of the ingredients to one another.
For example, U.S. Pat. No. 4,259,314 to Lowey employs a mixture of cellulose ethers--hydroxypropylmethylcellulose ("HPMC") and hydroxypropyl cellulose--to form a sustained release matrix in which the cellulose ether mixture has a weighted average viscosity rating of 250-4500 cps, and preferably 1200-2900 cps. These are equilibrated under an atmosphere having up to 40% relative humidity and then pre-mixed together before drying to a moisture content of 1% or less. The active and other remaining ingredients (after they have equilibrated under .ltoreq.40% humidity) are combined with the cellulose ether mixture and the resulting combination is compressed at .ltoreq.40% humidity to produce a tablet.
U.S. Pat. No. 5,451,409 to Rencher et al. discloses a dry mixed pseudoephedrine tablet in which a mixture of hydroxypropyl cellulose and hydroxyethyl cellulose forms the sustained release matrix; 0.5-10% HPMC is also added as a binder.
U.S. Pat. No. 5,085,865 to Nayak discloses a two-layer tablet wherein one layer, which may be formed using a dry mixing process, comprises a 60 mg pseudoephedrine controlled release matrix formulation. The matrix or "sustained release agent" comprises cellulose ethers--hydroxypropyl and/or hydroxyethyl cellulose--and, preferably also, sodium croscarmelose; this agent is present in an amount equivalent to at least twice that of pseudoephedrine. Up to half of the cellulose ether component may consist of HPMC.


A 6-pin electronic package includes a first side including a pair of first outer pins and a first middle pin, and a second side including a pair of second outer pins and a second middle pin. The first outer pins and the second middle pin are operatively coupled to a first circuit to provide a first function. The second outer pins and the first middle pin are operatively coupled to a second circuit to provide a second function. The 6-pin electronic package can be replaced on a circuit substrate with a first electronic package and a second electronic package that collectively include at least six pins. The 6-pin electronic package and the first and second electronic packages can be interchangeably used on a circuit substrate of an electronic device. The circuit substrate may include any one of the 6-pin electronic package mountable to the circuit substrate, and the first and second electronic packages. The first electronic package is mountable on the circuit substrate on a same footprint as the 6-pin electronic package. The second electronic package is mountable on the circuit substrate adjacent the first electronic package such that six pins of the first and second electronic packages share the same footprint as the pins of the 6-pin electronic package.

Electronic devices typically include a circuit substrate, such as a printed circuit board on which a number of electronic and/or optical components may be mounted. Each electronic and optical component may include one or more circuits that provide one or more functions for the electronic component. For example, an electronic component may include a single component circuit such as a transistor, or a multi-component circuit, such as a voltage regulator. Each component may include a number of inputs that provide data or signals to the component and a number of outputs that provide data or signals that may be generated in accordance with the function performed by the component.
Certain electronic components are commonly used in a variety of electronic devices. For example, almost every electronic device includes one or more transistors. Accordingly, standard electronic package configurations have been established by various industries in an attempt to standardize the size, shape, input and output pin arrangements, and various other characteristics of common electronic components.
A type of standardized electronic package is the SOT-23-6 (Small-Outline Transistor) package, which includes a rectangular enclosure that houses one or more single or multicomponent circuit(s) and includes six input/output pins. Three pins are arranged at equal distances on one side of the enclosure, while the remaining three pins are arranged in the same fashion on an opposite side of the enclosure. The pins are connected to the circuit(s) housed in the enclosure to provide input to and output from the circuit(s).
Another standardized electronic package is the SOT-23-3 package, which includes a rectangular enclosure that houses one or more single or multicomponent circuit(s) and includes three input/output pins. Two pins are arranged at equal distances on one side of the enclosure, while the remaining pin is arranged at the center of an opposite side of the enclosure. The pins are connected to the circuit(s) housed in the enclosure to provide input to and output from the circuit(s). The enclosure of the SOT-23-3 package is identical in size to the enclosure of the SOT-23-6 package. Additionally, the three pins of the SOT-23-3 package are arranged on the enclosure at the same locations as three corresponding pins of the SOT-23-6 package.
Yet another standardized electronic package is the SOT-23-5 package, which includes a rectangular enclosure that houses one or more single or multicomponent circuit(s) and includes five input/output pins. Two pins are arranged at equal distances on one side of the enclosure, while three pins are arranged equal distances on an opposite side of the enclosure. The pins are connected to the circuit(s) housed in the enclosure to provide input to and output from the circuit(s). The enclosure of the SOT-23-5 package is identical in size to the enclosure of the SOT-23-6 package. Additionally, the five pins of the SOT-23-5 package are arranged on the enclosure at the same locations as five corresponding pins of the SOT-23-6 package.
Because a pair of SOT-23-3 packages collectively have six pins, a pair of SOT-23-3 packages, with each performing a single function, may be substituted on a circuit substrate for a single SOT-23-6 package that performs both functions. Additionally, because a SOT-23-3 package and a SOT-23-5 package collectively have at least six pins, with each performing a single function, they may be substituted on a circuit substrate for a single SOT-23-6 package that performs both functions. However, the space used by the pair of SOT-23-3 packages or a SOT-23-3 package and a SOT-23-5 package may exceed the available space on the substrate where the SOT-23-6 package was mounted due to the pin arrangements of the SOT-23-6 package, any one of the SOT-23-3 packages, and the SOT-23-5 package. The space on the circuit substrate where the SOT-23-6 package was mounted may not be usable by any of the SOT-23-3 packages and/or the SOT-23-5 package.
Therefore, there is a need for a single 6-pin electronic package that can be replaced with a pair of similarly sized and arranged electronic packages that collectively include at least six pins on circuit substrates where space is limited.

Single or dual electronic package with footprint and pin sharing


The invention relates to a bimetallic casting serving as a wear piece in vertical mills and its method of manufacture. It includes a core (13) made of a ductile cast iron and provided with mechanical bonding elements in the form of pins (15) which are rendered integral with an outer casing (17) by casting, the outer casing being made of a non-ductile wear material having a high chromium content. Such castings are used for being mounted on the hub of a roller of a so-called vertical-axis crushing mill.

Vertical mills consist of rollers rotating about a vertical axis on a crushing track. The crushing rollers are mounted on a central hub and are provided at their periphery with wear pieces which may take the form of segments or which may also be constituted in monobloc form.
These wear pieces are made of cast iron having a high abrasion strength, especially cast irons having a high chromium content and, consequently, are not ductile at all (their value of elongation at break is virtually equal to zero). The wear pieces are generally fastened with the aid of clamps to the hub. Due to their lack of ductility, cracks or fissures may be observed to appear under the stresses due to the various mechanical stressings, these-cracks or fissures propagating into the said pieces. Under the effect of the stresses, various other drawbacks become apparent, including, in particular, deformation of the hub. This deformation of the hub causes considerable difficulties when replacing the wear pieces and it is common to have to replace both the wear piece and the hub.
In addition, the wear piece is particularly difficult to machine after casting because of its specific properties, namely its high hardness, whereas tolerances lower than H9 are required for these machinings.
In Document GB-2 078 575 A, weldable wear pieces are described which consist of a weldable steel part provided with protrusions which, after having been placed in a mould, undergoes metallurgico-mechanical bonding obtained on casting a cast iron. These pieces are described as being able to be suitable for various uses, such as engineering castings and tools. For the cast wear part, it is proposed to use a spheroidal graphite cast iron of low wear resistance and of low weldability in which a hard metal is incorporated.
Combined metallurgico-mechanical bonding is described as making it possible to compensate for the tensions resulting from the differences in expansion coefficient between the basis alloy (graphitic cast iron) and the reinforcing material incorporated into the wear part, thus ensuring a good bond between this wear part and the weldable part and preventing the propagation of microcracks.
Document AU-B-44415/89 (Acceptance no 617891) describes a method of producing a composite wear resistant product comprising a white iron casting joined to a steel or iron backing, said method including the steps of positioning in a mould at least two steel inserts having protruding locking fingers, casting the white iron over the steel inserts and the protruding locking fingers whereby the inserts are metallurgically and mechanically locked to the white iron, and after cooling of the white iron welding the inserts together to form the backing of the product.
However, the Applicant has noticed that none of the solutions is entirely satisfactory, on the one hand because it limits the use of very hard compositions for the wear part since it is necessary to provide a metallurgico-mechanical bond or welding, and on the other hand because such a bond or welding does not sufficiently prevent cracks and microcracks from propagating but rather facilitates cracks and microcracks. This phenomenon is particularly observed in the case of large vertical mills.

Bimetallic casting serving as a wear piece in vertical crushing mills and its method of manufacture


The two output currents (INP, IN) which are produced by a current source digital/analog converter (DAC) are supplied to the two halves of a symmetrical transimpedance amplifier. The input current (INP, IN) is supplied to a first stage, which is formed by a first transistor (N2), and a potential at the output of the first stage is supplied to a second stage, which is formed by a second transistor (N3), and the output voltage (VOUT, VOUTP) is formed by a potential at the output of the second stage. The output of the second stage is coupled to the output of the first stage through a Miller capacitor (Cm). The output of the transimpedance amplifier is coupled to its input by means of a connecting line which contains a feedback resistor (Rf).

In wire-free baseband applications such as UMTS, WLAN as well as digital television and Bluetooth, digital data is converted to analog signals by means of a digital/analog converter (DAC). The analog signals are then up-mixed to the carrier frequency, are post-filtered and are emitted by means of the power amplifier via the antenna to the air interface. In the baseband applications that have been mentioned, broadband modulation methods such as OFDM, DSSS or other broadband modulation methods are used. These modulation methods make better use of the channel bandwidth and thus achieve higher data rates. The linearity, the phase response and attenuation response of the DAC output are subject to stringent requirements resulting from the broadband modulation methods.
FIG. 1 shows a 9-bit current source DAC with 512 individual current sources. Each current source has a switch, which receives a binary signal from a decoder. This signal determines whether a current source is connected to the node Vout,p or to the node Vout,n. If the digital word is altered by an LSB (Least Significant Bit), a current source is switched from Vout,p to Vout,n. Depending on the bit number, the DAC is fully segmented or partially segmented. If the digital word (000000000) is applied to the DAC, 512 current sources are connected to Vout,n, and no current sources are connected to Vout,p. The digital word (111111111) is applied when fully driven, with all of the current sources being connected to Vout,p and none to Vout,n. As can be seen from FIG. 1, the output currents are converted across the resistors to a differential output voltage Voutdiff=Vout,p−Vout,n.
Various circuit arrangements by means of which the two DAC output currents can be converted to a differential output voltage are known from the prior art. The simplest option is to convert the output currents from the DAC directly to two output voltages across the two resistors illustrated in FIG. 1. This solution is highly linear and does not produce any additional harmonics. The phase and attenuation response are influenced only by that pole which is produced across the resistors with the load capacitances. Another known circuit arrangement amplifies the difference voltage across the DAC output resistors using an inverting differential amplifier circuit. It has been found that these known circuit arrangements do not satisfactorily ensure one major aim, specifically the maintenance of the phase and attenuation profile. For this purpose, it is necessary for the converter to have a high gain/bandwidth product, and for no additional poles and null points to be introduced into the current/voltage transfer function during conversion of the DAC output current to the output voltage. The known circuits arrangements do not have these characteristics to an adequate extent.

Transimpedance amplifier with a high gain/bandwidth product for conversion of a DAC output current


The present invention relates to a novel ethylene/pentene-1 copolymer whose molded film has a good balance between impact resistance and tear properties and high transparency, also is prominently reduced in a variation of the transparency even after subjected to a heat treatment, and further shows high blocking resistance, provided that the copolymer fulfills specific requisites. The invention also relates to a process for the preparation of the above-mentioned ethylene/pentene-1 copolymer and a formulation of the ethylene/pentene-1 copolymer composition using a stabilizer. According to the invention, there can be obtained an ethylene/pentene-1 copolymer composition which is excellent in heat stability in the molding stage, long-term heat stability and weatherability.

Linear low-density polyethylene (LLDPE), that is a copolymer of ethylene and .alpha.-olefin, shows higher impact strength when molded into a film, as compared with conventional low-density polyethylene (LDPE) obtained by the high pressure process, so that the linear low-density polyethylene has been broadly used as a film-forming material.
A film obtained from an ethylene/butene-1 copolymer (i.e., an example of the linear low-density polyethylenes) is excellent in tear properties because of its adequate tear strength, but is somewhat low in the impact strength.
A film obtained from a copolymer of ethylene and .alpha.-olefin having 6 or more carbon atoms (i.e, other example of the linear low-density polyethylene) is excellent in the impact strength, but has such a problem that the film cannot be easily torn because of too high tear strength. In other words, the film obtained from such copolymer is bad in the tear properties.
Accordingly, eagerly desired are ethylene/.alpha.-olefin copolymers which can provide films of high impact strength and excellent tear properties. For the purpose of more improving the impact strength of films, a method of using .alpha.-olefin having larger number of carbon atoms has been tried. However, the method sometimes causes such problems that the blocking resistance of the resulting film is much lowered and the transparency of the film is markedly reduced when the film is subjected a heat treatment. Especially in the case of a lamination film, after the film-forming procedure, the obtained film is generally subjected to an aging procedure at approx. 40.degree. C. to enhance the dimensional stability, but in this aging procedure, the film sometimes turns white so that the transparency is reduced.
The present inventors have earnestly studied to solve the above-mentioned problems accompanied by the ethylene/.alpha.-olefin copolymer films. As a result, they have found that if an ethylene/pentene-1 copolymer having been obtained by copolymerizing ethylene and pentene-1 under specific conditions and fulfilling specific requisites is molded into a film, the resulting film is excellent in blocking resistance as well as in a balance between impact strength and tear properties and is remarkably prevented from lowering of transparency caused by a heat treatment. Thus, ethylene/pentene-1 copolymers and processes for the preparation of the same according to the invention have been accomplished.
The present inventors have also found that an ethylene/pentene-1 copolymer composition obtained by adding a specific stabilizer to the above-mentioned ethylene/pentene-1 copolymer is excellent in heat stability in the molding stage, long-term heat stability and weatherability, and that a molded product obtained from the copolymer composition can keep high impact strength and good tear properties both inherently belonging to the ethylene/pentene-1 copolymer. Thus, ethylene/pentene-1 copolymer compositions according to the invention have been accomplished.

Ethylene/pentene-1 copolymer, and ethylene/pentene-1 copolymer composition