A microelectronic package has a microelectronic element and conductive posts or masses projecting above a surface of the substrate. Conductive elements at a surface of the substrate opposite therefrom are electrically interconnected with the microelectronic element. An encapsulant overlies at least a portion of the microelectronic element and may be in contact with the conductive posts or masses. The encapsulant may have openings permitting electrical connections with the conductive posts or masses. The openings may partially expose conductive masses joined to posts, fully expose top surfaces of posts and partially expose edge surfaces of posts, or may partially expose top surfaces of posts.

Microelectronic devices such as semiconductor chips typically require many input and output connections to other electronic components. The input and output contacts of a semiconductor chip or other comparable device are generally disposed in grid-like patterns that substantially cover a surface of the device (commonly referred to as an "area array") or in elongated rows which may extend parallel to and adjacent each edge of the device's front surface, or in the center of the front surface. Typically, devices such as chips must be physically mounted on a substrate such as a printed circuit board, and the contacts of the device must be electrically connected to electrically conductive features of the circuit board.
Semiconductor chips are commonly provided in packages that facilitate handling of the chip during manufacture and during mounting of the chip on an external substrate such as a circuit board or other circuit panel. For example, many semiconductor chips are provided in packages suitable for surface mounting. Numerous packages of this general type have been proposed for various applications. Most commonly, such packages include a dielectric element, commonly referred to as a "chip carrier" with terminals formed as plated or etched metallic structures on the dielectric. These terminals typically are connected to the contacts of the chip itself by features such as thin traces extending along the chip carrier itself and by fine leads or wires extending between the contacts of the chip and the terminals or traces. In a surface mounting operation, the package is placed onto a circuit board so that each terminal on the package is aligned with a corresponding contact pad on the circuit board. Solder or other bonding material is provided between the terminals and the contact pads. The package can be permanently bonded in place by heating the assembly so as to melt or "reflow" the solder or otherwise activate the bonding material.
Many packages include solder masses in the form of solder balls, typically about 0.1 mm and about 0.8 mm (5 and 30 mils) in diameter, attached to the terminals of the package. A package having an array of solder balls projecting from its bottom surface is commonly referred to as a ball grid array or "BGA" package. Other packages, referred to as land grid array or "LGA" packages are secured to the substrate by thin layers or lands formed from solder. Packages of this type can be quite compact. Certain packages, commonly referred to as "chip scale packages," occupy an area of the circuit board equal to, or only slightly larger than, the area of the device incorporated in the package. This is advantageous in that it reduces the overall size of the assembly and permits the use of short interconnections between various devices on the substrate, which in turn limits signal propagation time between devices and thus facilitates operation of the assembly at high speeds.
Assemblies including packages can suffer from stresses imposed by differential thermal expansion and contraction of the device and the substrate. During operation, as well as during manufacture, a semiconductor chip tends to expand and contract by an amount different from the amount of expansion and contraction of a circuit board. Where the terminals of the package are fixed relative to the chip or other device, such as by using solder, these effects tend to cause the terminals to move relative to the contact pads on the circuit board. This can impose stresses in the solder that connects the terminals to the contact pads on the circuit board. As disclosed in certain preferred embodiments of U.S. Pat. Nos. 5,679,977; 5,148,266; 5,148,265; 5,455,390; and 5,518,964, the disclosures of which are incorporated by reference herein, semiconductor chip packages can have terminals that are movable with respect to the chip or other device incorporated in the package. Such movement can compensate to an appreciable degree for differential expansion and contraction.
Testing of packaged devices poses another formidable problem. In some manufacturing processes, it is necessary to make temporary connections between the terminals of the packaged device and a test fixture, and operate the device through these connections to assure that the device is fully functional. Ordinarily, these temporary connections must be made without bonding the terminals of the package to the test fixture. It is important to assure that all of the terminals are reliably connected to the conductive elements of the test fixture. However, it is difficult to make connections by pressing the package against a simple test fixture such as an ordinary circuit board having planar contact pads. If the terminals of the package are not coplanar, or if the conductive elements of the test fixture are not coplanar, some of the terminals will not contact their respective contact pads on the test fixture. For example, in a BGA package, differences in the diameter of the solder balls attached to the terminals, and non-planarity of the chip carrier, may cause some of the solder balls to lie at different heights.
These problems can be alleviated through the use of specially constructed test fixtures having features arranged to compensate for non-planarity. However, such features add to the cost of the test fixture and, in some cases, introduce some unreliability into the test fixture itself. This is particularly undesirable because the test fixture, and the engagement of the device with the test fixture, should be more reliable than the packaged devices themselves in order to provide a meaningful test. Moreover, devices used for high-frequency operation are typically tested by applying high frequency signals. This requirement imposes constraints on the electrical characteristics of the signal paths in the test fixture, which further complicates construction of the test fixture.
Additionally, when testing packaged devices having solder balls connected with terminals, solder tends to accumulate on those parts of the test fixture that engage the solder balls. This accumulation of solder residue can shorten the life of the test fixture and impair its reliability.
A variety of solutions have been put forth to deal with the aforementioned problems. Certain packages disclosed in the aforementioned patents have terminals that can move with respect to the microelectronic device. Such movement can compensate to some degree for non-planarity of the terminals during testing.
U.S. Pat. Nos. 5,196,726 and 5,214,308, both issued to Nishiguchi et al., disclose a BGA-type approach in which bump leads on the face of the chip are received in cup-like sockets on the substrate and bonded therein by a low-melting point material. U.S. Pat. No. 4,975,079 issued to Beaman et al. discloses a test socket for chips in which dome-shaped contacts on the test substrate are disposed within conical guides. The chip is forced against the substrate so that the solder balls enter the conical guides and engage the dome-shaped pins on the substrate. Sufficient force is applied so that the dome-shaped pins actually deform the solder balls of the chip.
A further example of a BGA socket may be found in commonly assigned U.S. Pat. No. 5,802,699, issued Sep. 8, 1998, the disclosure of which is hereby incorporated by reference herein. The '699 patent discloses a sheet-like connector having a plurality of holes. Each hole is provided with at least one resilient laminar contact extending inwardly over a hole. The bump leads of a BGA device can be advanced into the holes so that the bump leads are engaged with the contacts. The assembly can be tested, and if found acceptable, the bump leads can be permanently bonded to the contacts.
Commonly assigned U.S. Pat. No. 6,202,297, issued Mar. 20, 2001, the disclosure of which is hereby incorporated by reference herein, discloses a connector for microelectronic devices having bump leads and methods for fabricating and using the connector. In one embodiment of the '297 patent, a dielectric substrate has a plurality of posts extending upwardly from a front surface. The posts may be arranged in an array of post groups, with each post group defining a gap therebetween. A generally laminar contact extends from the top of each post. In order to test a device, the bump leads of the device are each inserted within a respective gap thereby engaging the contacts which wipe against the bump lead as it continues to be inserted. Typically, distal portions of the contacts deflect downwardly toward the substrate and outwardly away from the center of the gap as the bump lead is inserted into a gap.
Commonly assigned U.S. Pat. No. 6,177,636, the disclosure of which is hereby incorporated by reference herein, discloses a method and apparatus for providing interconnections between a microelectronic device and a supporting substrate. In one preferred embodiment of the '636 patent, a method of fabricating an interconnection component for a microelectronic device includes providing a flexible chip carrier having first and second surfaces and coupling a conductive sheet to the first surface of the chip carrier. The conductive sheet is then selectively etched to produce a plurality of substantially rigid posts. A compliant layer can be provided on the second surface of the support structure and a microelectronic device such as a semiconductor chip is engaged with the compliant layer so that the compliant layer lies between the microelectronic device and the chip carrier, and leaving the posts projecting from the exposed surface of the chip carrier. The posts are electrically connected to the microelectronic device. The posts form projecting package terminals that can be engaged in a socket or solder-bonded to features of a substrate as, for example, a circuit panel. Because the posts can be movable with respect to the microelectronic device, such a package can substantially accommodate thermal coefficient of expansion mismatches between the device and a supporting substrate when the device is in use. Moreover, the tips of the posts can be coplanar or nearly coplanar.
Despite all of the above-described advances in the art, still further improvements in making or testing microelectronic packages would be desirable.

Stackable molded microelectronic packages


A method for dynamic optimization of thread assignments for application workloads in an simultaneous multi-threading (SMT) computing environment includes monitoring and periodically recording an operational status of different processor cores each supporting a number of threads of the thread pool of the SMT computing environment and also operational characteristics of different workloads of a computing application executing in the SMT computing environment. The method further can include identifying by way of the recorded operational characteristics a particular one of the workloads demonstrating a threshold level of activity. Finally, the method can include matching a recorded operational characteristic of the particular one of the workloads to a recorded status of a processor core best able amongst the different processor cores to host execution in one or more threads of the particular one of the workloads and directing the matched processor core to host execution of the particular one of the workloads.

1. Field of the Invention
The present invention relates to parallel computing in general and more particularly to operating system optimization in a parallel computing environment.
2. Description of the Related Art
Parallel computing is a form of computation in which many calculations are carried out simultaneously, operating on the principle that large problems can often be divided into smaller ones, which are then solved concurrently. There are several different forms of parallel computing, for example bit-level, instruction level, data, and task parallelism. Parallelism has been employed for many years, mainly in high-performance computing. More recently, parallel computing has become the dominant paradigm in computer architecture, mainly in the form of multicore processors.
Parallel computers can be classified according to the level at which the computing hardware platform supports parallelism—with multi-core and multi-processor computers having multiple processing elements within a single machine, while clusters and grids using multiple computers to work on the same task. Specialized parallel computer architectures are sometimes used alongside traditional processors, for accelerating specific tasks. The advent of simultaneous multi-threading (SMT) operating environments specifically supports parallelism by executing more than one thread on a processor core and assigning different tasks of a computer program to different threads.
Thus, managing the assignment and execution of different processing tasks to different threads of execution can in of itself require sophisticated programmatic logic. While more programs can run simultaneously in an SMT environment, the performance of some of programs may show some degradation. Consequently, administrators become unsure about the effectiveness of SMT for workloads of interest and ultimately disable intelligent usage of SMT. Ironically, based upon the exhibited degradation of the workloads of interest, the administrator subsequent to SMT deactivation can experience a decrease in throughput of the workload of interest while the performance of the individual applications of the workload of interest are ensured.
Even still, in large enterprise level systems, the numerous tasks running on huge systems face performance issues that often cannot be recreated for troubleshooting, but can most-often be traced to non-optimal utilization of the system. In this regard, not only are the workloads varying constantly, but also the characteristics of a single application can vary from time to time. Of note, program characteristics determine whether leveraging of SMT will help increase to throughput or if the use of SMT will degrade performance of a subject workload. Given the dynamic nature of the workloads that run on the system, the SMT control has to be dynamic as well. Notwithstanding, current methodologies permit either a system-wide activation or de-activation of SMT and do not allow for a partial activation, or even dynamic SMT control. Consequently, critical resources of the computing environment are likely to be wasted.

Dynamic operating system optimization in parallel computing

International Business Machines Corporation


A lead frame for a semiconductor device. The lead frame has opposite first and second sides bounded respectively by first and second parallel reference planes between which a thickness is defined. The lead frame has a support with a surface at the first side of the lead frame for receiving a semiconductor chip. A plurality of leads are spaced from the support to be electrically connected to a semiconductor chip on the support. A first lead in the plurality of leads has a length between first and second ends and a width taken transversely to the length. The first end of the first lead has a first region that has a thickness less than the thickness of the first lead at the second end of the first lead so that at least a part of the first region is offset from the second reference plane toward the first reference plane. The first end of the first lead has at least a first protrusion projecting away from the first reference plane.

1. Field of the Invention
This invention relates to lead frames for semiconductor devices and to a semiconductor device incorporating such a lead frame.
2. Background Art
There has been a trend in recent years to minimize the size of semiconductor devices. This makes possible the compact and lightweight construction of electronic appliances, and the like, incorporating the semiconductor devices. As examples of appliances, for which size and weight are key design considerations, are portable telephones, PDA devices, as well as myriad other portable electronic appliances used in many diverse environments and for different purposes. Various designs of semiconductor devices have evolved over the years to achieve the ends of miniaturization, thickness reduction and weight reduction. These devices are commonly referred to as TBGA that use a lead frame and TAB (tape automated bonding) tape, BGA (Ball Grid Array), and CSP (chip size package) that use flexible printed circuit boards. Options include wafer-scale CSP, which is the same size as the chip, and CSP, which is somewhat larger than the chip.
Of these devices, particular interest has been paid to semiconductor devices of the type wherein leads are exposed at a flat face within the confines of a resin sealed package, rather than on the edges thereof. Exemplary packages are those referred to as SON (small outline non-leaded package) and QFN (quad flat non-leaded package). Conventional lead frames of this type are shown in FIGS. 11-18 herein.
More specifically, as shown in FIGS. 11 and 12, it is known to form a generally rectangular lead 10 and, through a half-etching process, form an undercut 12 through one surface 14 thereof. The undercut 12 defines a receptacle 16 for an encapsulating, sealing material, which is molded around the lead 10 in a manner so as to leave the surface 14 exposed through the sealing material. By causing the sealing material to migrate into the receptacle 16, the tendency of the lead 10 to separate from the encapsulating, sealing material is diminished.
While the undercut 12 facilitates bonding of the encapsulating material to the lead 10, the undercut 12 also weakens the lead 10 so as to cause a condition shown in FIG. 12, resulting from the electrical connection of a conductive element/wire 17 to the lead 10. Under the force induced by a tool 18 used in electrically connecting the conductive element/wire 17 to the lead 10, the thinned lead end 19 may bend at a line 20 coinciding with the edge of the undercut 12 so that the requisite pressure to establish the connection cannot be applied. This may cause load problems and degradation of ultrasound transfer efficiency. The inherent flexibility of the thinned lead end 19 may make stabilization of the lead end 19 during processing difficult or impossible.
To overcome this problem, it is known to stabilize the thinned lead end 19 during the electrical connection process. As seen in FIG. 13, a heat block 22 bears on one side 23 of a lead frame sheet 24 from which the lead 10 and a support 25, upon which a semiconductor chip 26 is mounted, are formed. To avoid the deformation as shown in FIG. 12, the heat block 22 is provided with an adapter 27 which nests supportingly under the lead undercut 12.
The use of the adapters has drawbacks. First of all, modifying the heat blocks may have to be done in many different manners to accommodate different configurations of leads. Thus, it may not be possible to develop a universal heat block form.
Additionally, with batch mold type lead frames (MAP: Mold Array Package), it may not be possible to place adapters on the heat blocks. As a result, there may be defects in the bonding of the conductive elements/wires to the leads. This problem may be further aggravated by the application of a tape conventionally used to prevent leakage of the sealing resin material during the molding process.
In FIGS. 14 and 15, a lead 10xe2x80x2, similar to the lead 10 in FIGS. 11 and 12, is shown with an undercut 12xe2x80x2, produced by a half-etching process, so as to reduce the thickness T of the lead end 30 from the starting thickness T1 at the opposite lead end 32.
In FIGS. 16-18, a conventional half-etching process is depicted to sequentially form undercut/thinned leads 10, 10xe2x80x2 from a starting lead frame sheet 36. Resist elements 38 are strategically placed on one side 40 of the lead frame sheet 36 to shield the region over which the leads 10, 10xe2x80x2 are to be formed. The opposite side 42 of the lead frame sheet 36 has strategically located resist elements 44 placed thereon so as to leave the region of the lead frame sheet 36 underlying the resist elements 38 exposed. With the lead frame sheet 36 and resist elements 38, 44 in the FIG. 16 relationship, etching is undertaken so as to progressively wear away the lead frame sheet 36, thereby to form grooves 46 at the one side 40 of the lead frame sheet 36 between the resist elements 38, and a single groove 48 on the opposite side 42 of the lead frame sheet 36 between the resist elements 44. Etching continues from the FIG. 17 state until the grooves 46, 48 become contiguous, thereby producing the leads 10, 10xe2x80x2, which may have the same, or similar, construction to the formed leads 10, 10xe2x80x2, in FIGS. 11, 12 and 14, 15, respectively.
In one form, the invention is directed to a lead frame for a semiconductor device. The lead frame has opposite first and second sides bounded respectively by first and second parallel reference planes between which a thickness is defined. The lead frame has a support with a surface at the first side of the lead frame for receiving a semiconductor chip. A plurality of leads are spaced from the support to be electrically connected to a semiconductor chip on the support. A first lead in the plurality of leads has a length between first and second ends and a width taken transversely to the length. The first end of the first lead has a first region that has a thickness less than the thickness of the first lead at the second end of the first lead so that at least a part of the first region is offset from the second reference plane toward the first reference plane. The first end of the first lead has at least a first protrusion projecting away from the first reference plane.
In one form, the protrusion has a width less than the width of the first lead and the first end of the first lead is closer to the support than is the second lead end.
The protrusion may project towards but not fully to the second reference plane.
In one form, the protrusion tapers to an apex.
The apex may be substantially a point with the first lead viewed in cross section taken transversely to the length of the first lead.
In one form, the first lead has spaced first and second edges between which the width of the first lead is defined and the protrusion is substantially centered between the first and second edges.
In one form, the protrusion has a lengthwise extent along the length of the first lead over substantially the entire first region.
The protrusion may be centered between the first and second edges over the entire lengthwise extent of the protrusion.
In one form, the protrusion tapers to a linear apex.
The first lead may have a second protrusion projecting away from the first reference plane at a location spaced lengthwise of the first lead from the first protrusion.
The second protrusion may have a width less than the first lead.
The second protrusion may taper to an apex.
The region of the first lead may be formed by an etching process.
The invention contemplates the above lead frame in combination with a semiconductor chip mounted on the surface of the support.
The invention further contemplates a semiconductor device, consisting of the above-described lead frame with a semiconductor mounted to the support surface, a conductive element electrically connecting the semiconductor chip to the first lead, and a sealing material. The sealing material covers the semiconductor chip and is applied to a surface of the first lead between first and second ends of the first lead between the first and second reference planes at the first region of the first lead so that the second end of the first lead is exposed.
The first protrusion may be fully covered by the sealing material between the first and second ends of the first lead.
In one form, the conductive element connects to the first lead closer to the first end of the first lead than to the second end of the first lead.

Lead frame for a semiconductor device and a semiconductor device incorporating the lead frame


To realize a high performance display at a low cost and a high mounting yield of the driving circuit. An electro-optical device according to the present invention comprises an element substrate having a plurality of pixels and a plurality of data lines electrically connected to the plurality of pixels, a circuit substrate piece mounted on the element substrate and having a first circuit which is connected to the plurality of data lines and has a plurality of thin film transistors, and an integrated circuit mounted on the circuit substrate piece and having a second circuit which is connected to the first circuit for driving the plurality of pixels via the first circuit and the plurality of data lines.

The present invention relates to an electro-optical device such as a liquid crystal device and an electronic apparatus comprising the same, such as a liquid projector.
Such electro-optical devices comprise, on an element substrate, a plurality of pixels and a driving circuit for driving the plurality of pixels, while active matrix driving electro-optical devices further comprise pixel switching elements serving as active elements for every pixel. In an electro-optical device such as a liquid crystal display formed by using a liquid crystal device, the structure of the plurality of pixels or the driving circuit usually varies depending on their sizes or performances thereof. Specifically, each pixel switching element in each of the plurality of pixels is made of amorphous silicon or low-temperature polysilicon according to the size or the performance of the liquid crystal display. Furthermore, the driving circuit is mounted on the element substrate as an IC (Integrated Circuit) or an LSI (Large Scale Integration), or the driving circuit is formed in such a way that circuit elements are formed on the element substrate by using the low-temperature polysilicon technique or technology. That is, various types of liquid crystal displays can be manufactured by selecting an appropriate technology from the IC, the LSI, the low-temperature polysilicon technology, and the amorphous silicon technology in view of their the technical properties.
Here, in the driving circuit for a liquid crystal device, if the circuit elements are made of the amorphous silicon, there is a possibility that the driving circuit will not properly operate due to the low current driving efficiency of the circuit. Therefore, the circuit elements may be formed by using the low-temperature polysilicon having higher current driving efficiency than the amorphous silicon, or alternatively the driving circuit may be formed with a plurality of pixels on the element substrate.
In addition, in Patent Document 1, a technology for providing a driving circuit which comprises, as circuit elements, transistors formed on a substrate different from the element substrate by using the low-temperature polysilicon is disclosed. Further, in Patent Document 2, another technology in which a substrate having formed with a driving circuit which has circuit elements formed by using the low-temperature polysilicon is mounted on another substrate, to reduce noise during the driving operation is disclosed.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 8-250745
[Patent Document 2] Japanese Unexamined Patent Application Publication No. 2000-214477

Electro-optical device and electronic apparatus


The present invention generally relates to an apparatus and a method for conveying and operating tools into a wellbore. In one aspect, a method of performing a downhole operation in a wellbore is provided. The method includes pushing a continuous rod into the wellbore, wherein the continuous rod includes a member disposed therein. The method further includes positioning the continuous rod proximate at a predetermined location in the wellbore and performing the downhole operation. In yet another aspect, a system for performing a downhole operation in a wellbore is provided.

1. Field of the Invention
The present invention generally relates to the operation of instrumentation within a wellbore. More particularly, the invention relates to an apparatus and a method for conveying and operating tools into a wellbore.
2. Description of the Related Art
In the drilling of oil and gas wells, a wellbore is formed using a drill bit that is urged downwardly at a lower end of a drill string. After drilling a predetermined depth, the drill string and the drill bit are removed, and the wellbore is lined with a string of steel pipe called casing. The casing provides support to the wellbore and facilitates the isolation of certain areas of the wellbore adjacent hydrocarbon bearing formations. An annular area is thus defined between the outside of the casing and the earth formation. This annular area is typically filled with cement to permanently set the casing in the wellbore and to facilitate the isolation of production zones and fluids at different depths within the wellbore. Numerous operations occur in the well before or after the casing is secured in the wellbore. Many operations require the insertion of some type of instrumentation or hardware within the wellbore. For instance, logging tools are employed in the wellbore to determine various formation or structural parameters including hydrocarbon saturation and cement bond integrity.
Early oil and gas wells were typically drilled in a vertical or near vertical direction with respect to the surface of the earth. As drilling technology improved and as economic and environmental demands required, an increasing number of wells were drilled at angles which deviated significantly from vertical. In the last several years, drilling horizontally within producing zones became popular as a means of increasing production by increasing the effective wellbore wall surface exposed to the producing formation. It is not uncommon to drill sections of wellbores horizontally (i.e. parallel to the surface of the earth) or even "up-hill" where sections of the wellbore were actually drilled toward the surface of the earth.
The advent of severely deviated wellbores introduced several problems in the performance of some wellbore operations. Conventional logging was especially impacted. Conventional logging utilizes the force of gravity to convey logging instrumentation into a wellbore. Gravity is not a suitable conveyance force in highly deviated, horizontal or up-hill sections of wellbores. Numerous methods have been used, with only limited success, to convey conventional instrumentation or "tools" in highly deviated conditions. These methods include the use of conveyance members such as electric wireline, slickline, coiled tubing, or jointed pipe.
Electric wireline or "wireline" is generally a multi-strand wire or cable for use in oil or gas wells. Wireline typically comprises at least a single conductor cable surrounded by a plurality of braided non-conductive cables. The non-conductive cables provide structural support for the single conductor cable during transport of the wireline into the wellbore. In a logging operation, a logging tool is attached to the wireline and then the tool string is either lowered into the wellbore utilizing the force of gravity or pulled into the wellbore by a tractor device. As discussed above, gravity is not a suitable conveyance force in highly deviated, horizontal, or up-hill sections of wellbores, and tractor devices are expensive and complex.
A slickline is generally a single-strand non-conductive wire with an outer diameter between 5/16″ to ⅜″. Due to the slickline's small diameter (particularly in relation to typical wellbore diameters) and hence minimal columnar buckling resistance, slickline cannot be pushed or urged into the wellbore, but rather slickline must rely on utilizing the force of gravity. For example, in a logging operation, a logging tool is attached to the slickline and then the tool string is lowered into the wellbore utilizing the force of gravity. As discussed above, gravity is not a suitable conveyance force in highly deviated, horizontal, or up-hill sections of wellbores. Both slickline and wireline are "impossible" to push for any appreciable distance in a wellbore. The old adage "like pushing a rope" indicating extremely difficult is applicable to attempts to deploy wireline or slickline by means of axial force applied from the surface (of the Earth). The structural component of wireline is typically braided cable. As such, wireline performs reasonably well under axial tension, but particularly poorly under axial compression. The buckling strength of wireline having a given apparent diameter is greatly diminished because the strands of cable comprising the wireline are capable of relative axial movement. Even slickline, which is typically single strand construction, has a fairly low buckling strength because of its small diameter (and therefore large length to diameter ratio when deployed).
Coiled tubing can be "pushed" into a wellbore more readily than wireline or slickline but still has limitations. Coiled tubing is a long continuous length of spooled or "reeled" thin walled pipe. Coiled tubing units utilize hydraulic injector heads that push the coiled tubing from the surface, allowing it to reach deeper than slickline, but ultimately the coiled tubing stops as well. Coiled tubing is susceptible to a condition known as lockup. As the coiled tubing goes through the injector head, it passes through a straightener; but the tubing retains some residual bending strain corresponding to the radius of the spool. That strain gives the tubing a helical form when deployed in a wellbore. Therefore it winds axially along the wall of the wellbore like a long, stretched spring. Ultimately, when a long enough length of coiled tubing is deployed in the well bore, frictional forces from the wellbore wall rubbing on the coiled tubing cause the tubing to bind and lock up, thereby stopping its progression. Such lock up limits the use of coiled tubing as a conveyance member for logging tools in highly deviated, horizontal, or up-hill sections of wellbores.
Another limitation of coiled tubing is the limited capability of pushing coiled tubing into the wellbore due to known structural characteristics of coiled tubing. Coiled tubing comes in a range of diameters and wall thicknesses. For instance, coiled tubing could have a 1″ diameter with a wall thickness of 0.080″ to approximately a 3.5″ diameter with a wall thickness of 0.203″. The ability of a pipe to withstand buckling under axial end loading is proportional to the pipe diameter and the pipe wall thickness as indicted by generally accepted equations for calculating column buckling. In the Eulerian equation below for buckling of cylindrical cross sections under axial end loading, the critical buckling load Pcr is a function of material properties (properties of steel are most often applicable in the case of coiled tubing) and the outer and inner diameters of the cylindrical column (note: outer diameter minus inner diameter divided by two equals wall thickness).Pcr=4π3E(D4−d4)/64L2                 E=Youngs's Modulus for steel (3×107)        D=outer diameter        d=inner diameter        L=length
Further, the above equation illustrates that as the length of deployed tubing increases the load at which that tubing will buckle decreases. In a typical extended reach well (thousands of feet deep) readily coiled tubing buckles due to the friction loading between lower portions of the tubing and the walls of the wellbore. Once buckling occurs such frictional loading increases and ultimately exceeds the capacity of the surface equipment and/or the coiled tubing to sustain further loading. At that point, the coiled tubing has gone as far into the wellbore as it can go. Thus, the structural characteristics of coiled tubing limits the capability of using coiled tubing as a conveyance member for logging tools in highly deviated, horizontal, or up-hill sections of wellbores.
Further exacerbating the aforementioned buckling issue is the fact that coiled tubing is supplied from the manufacturer on a reel. For practical transportation and handling matters such reels have size (outer diameter) limits that are not to be exceeded. As such, coiled tubing is plastically deformed when reeled at the manufacturing mill because it must be made to fit on a given reel regardless of its cross-sectional diameter. The tubing is not only deformed axially by such installation on the reel, it is also deformed cross-sectionally such that it assumes a permanent ovality. Such "factory" ovality specifications are published by the various manufacturers of coiled tubing. The capability of employing coiled tubing in highly deviated, horizontal, or up-hill sections is therefore further limited due to the ovality of the coiled tubing because the ovality decreases the buckling resistance of the tubing. The ovality in conjunction with the residual axial strain (from being reeled) also causes the tubing to assume an inherent helical profile when deployed in a wellbore and therefore at even relatively small axial compression loads the tubing winds helically against the wall of the well bore thereby increasing its frictional engagement of that wall. Ovality also decreases the ability of the tube to resist collapse under external differential pressure. Thus, the ovality limits of coiled tubing also limits the capability of using coiled tubing as a conveyance member for logging tools in highly deviated, horizontal, or up-hill sections of wellbores.
Jointed pipe has been used for the deployment of certain downhole devices even where "pushing" is required. In a given diameter range jointed pipe has greater buckling resistance than any of wireline, slickline, or coiled tubing. Each threaded connection (typically every thirty feet) in a string of jointed pipe acts as a column stiffener and upset threaded connections also tend to stand the bulk of the pipe away from the wall of the wellbore thereby reducing cumulative frictional engagement. Jointed pipe is deficient in that it requires a rig (including some form of derrick or crane) for deployment and deployment is very time consuming. Each threaded connection must be made and unmade when correspondingly deploying or retrieving jointed pipe. The additional time consumption and the logistics of moving a rig onto a work location make the use of jointed pipe very expensive as compared with reeled deployment options such as wireline, slickline, and coiled tubing.
A need therefore exists for a reliable and operationally efficient apparatus and method to convey and operate a wellbore tool, such as a logging tool, in a wellbore which is deviated from the vertical.

Apparatus and methods for operating a tool in a wellbore


A control system for a brake vacuum pump, the system being capable of accumulating a negative pressure required for a vacuum chamber, without excessively operating the vacuum pump. In this system, an EGI_ECU determines whether a vehicle has experienced running at a speed equal to or higher than a preset creep vehicle speed after the startup of an engine. The EGI_ECU prohibits the operation of the vacuum pump until the time when the vehicle experiences running at a speed equal to or higher than the creep vehicle speed. Thereby, in a situation obviously not requiring a strong braking force, such as in a stopped state immediately after the startup of the engine, the operation of the vacuum pump can be prohibited, which allows the vacuum pump to be accurately prevented from an unnecessary drive.

1. Field of the Invention
The present invention relates to a control system for a brake vacuum pump, and more specifically, concerns a control system for the brake vacuum pump, the system performing the driving control of the vacuum pump that is connected to a vacuum chamber of a brake booster into which a negative pressure occurring in an intake manifold of an engine is introduced, and that assists the introduction of the negative pressure into the vacuum chamber.
2. Description of the Related Art
In a braking apparatus for a vehicle, the brake booster has been widely used for introducing the negative pressure occurring in the intake manifold of the engine into the vacuum chamber, and boosting a depression operating force against a brake pedal by making use of the negative pressure accumulated in the vacuum chamber.
In recent years, with a trend toward placing a throttle valve under electronic control for the purpose of improving exhaust emission characteristic, operating conditions in which a sufficient negative pressure is difficult to generate in the intake manifold, are on the increase. Furthermore, in recent times, for the purpose of enhancing the braking force in response to the upsizing of vehicle, there is a demand to keep the vacuum chamber in a deep negative pressure state (i.e., a low pressure state).
To cope with these situations, many techniques for assisting the introduction of negative pressure from the intake manifold to the vacuum chamber using the vacuum pump, have been proposed. For example, Japanese Unexamined Patent Application Publication No. 9-177678 discloses a technique for performing a driving control of the vacuum pump in response to the pressure state (absolute pressure or relative pressure) in the vacuum chamber (vacuum tank).
However, an arrangement that merely performs a driving control of the vacuum pump in response to a pressure state in the vacuum chamber as in the art disclosed in the above-described Japanese Unexamined Patent Application Publication No. 9-177678, may excessively operate the vacuum pump.
For example, when the negative pressure in the vacuum chamber temporarily becomes shallow (i.e., when the pressure becomes high) by a user performing repetitive braking operations in a short time, the vacuum pump may undesirably be operated even though the negative pressure can be quickly accumulated up to a predetermined value by using only the negative pressure occurring in the intake manifold.
Moreover, even in a situation not requiring so much braking force, such as before a starting state immediately after the startup of the engine, or in a constant running state at a relatively low speed, the vacuum pump may unfavorably be operated.
To overcome the above-described problems, the present invention is directed to a control system for the brake vacuum pump, the system being capable of accumulating the negative pressure required for the vacuum chamber, without excessively operating the vacuum pump.


A tape loading apparatus comprises a base, a roller post about which a tape is wrapped for tape loading, and a carrying member for carrying the roller post. The roller post includes a rotation shaft and a roller rotating about the rotation shaft, and a shaft engagement member is provided on the base for holding the roller post at a predetermined position, the shaft engagement member directly contacting and pressing one or both ends of the rotation shaft.

1. Field of the Invention
The present invention relates to a tape loading apparatus.
2. Description of the Related Art
Recently, in tape loading mechanisms for use in magnetic recording/reproduction apparatuses in which a tape is withdrawn out of a cassette and then wrapped about a rotary head cylinder, the position in the plane, and the height and inclination of a roller post provided on a carrying member are determined by pressing the carrying member to a positioning member provided on a chassis by a reference surface of the chassis and a pressing member.
Hereinafter, a conventional tape loading apparatus will be described with reference to Japanese Laid-Open Publications Nos. 4-318361 and 4-318356.
First, a conventional structure will be described with reference to Japanese Laid-Open Publication No. 4-318361. In this publication, FIG. 5 is a partial perspective view of a loading mechanism. Reference numerals 8, 10 and 11 indicate roller posts disposed on boats 14 and 15. Reference numeral 86 and 87 indicate stoppers provided on the chassis. Reference numeral 41 indicates a feed side ring gear (a take-up side loading ring is not shown in FIG. 5, see FIG. 6). Reference numerals 53 and 55 indicate, respectively, feed side and take-up side drive shafts provided on the respective feed side and take-up side ring gears. Reference numerals 17 and 18 indicate feed side and take-up side loading guides, respectively.
The feed side and take-up side loading rings are rotated by driving means. The boats 14 and 15 which are engaged with the respective feed side and take-up side loading rings are moved along the loading guides 17 and 18 to withdraw a tape out of a cassette for the purpose of tape loading. After completion of the loading, the boats 14 and 15 are pressed to the respective stoppers 86 and 87 to position the roller posts 8, 10 and 11.
The mechanism for positioning the boats 14 and 15 when the tape loading is completed will be described with reference to FIG. 15 of Japanese Patent No. 4-318361.
FIG. 15 of the above-described publication shows a mechanism for positioning the feed side boat 14. FIGS. 15(a), 15(b), 15(c) and 15(d) are a plan view, a side elevation view, a bottom plan view and a partial cross-sectional view, respectively. For the sake of clarification, the structure of each component is simplified.
In this figure, reference numeral 86 indicates a stopper provided on a chassis 1. A cone-like pressing portion 86b is provided on an upper portion of a pin 86a. Reference numeral 14a is a V-shaped groove provided at a front end of a feed side boat 14, which has a sloped portion. The feed side boat 14 is further provided with reference surfaces at the front and rear end portions thereof. The reference surfaces of the feed side boat 14 contacts and presses the reference surface of the chassis 1 when loading is completed, thereby making it possible to perform high-precision positioning.
As shown in FIGS. 5 and 15 in the above-described publication, as the feed side ring gear 38 is rotated, the feed side boat 14 is guided along the feed side loading guide 17. After completion of loading, the feed side boat 14 is in a position such that the stopper 86 contacts and presses the V-shaped groove 14a. A driving force is constantly exerted on the feed side boat 14 by a driving means (a shaking plate 45, not shown in FIGS. 5 and 15,) via a feed side drive shaft 53 in a direction indicated by P. Therefore, the stopper 86 contacts and presses the V-shaped groove 14a, so that the V-shaped groove 14a constrains the lateral position of the feed side boat 14. Meanwhile, a force is exerted to the feed side boat 14 in a direction indicated by F, so that the reference surfaces provided on the feed side boat 14 contact and press the reference surface provided on the chassis 1, thereby constraining the back-and-forth and up-and-down position of the feed side boat 14.
Next, a method for adjusting the height of the roller post will be described with reference to Japanese Laid-Open Publication No. 4-318356, since Japanese Laid-Open Publication No. 4-318361 does not describe this method.
In this publication, FIGS. 3, 4 and 5 are partial views of a conventional boat and roller post. FIG. 4 is an enlarged sectional view of FIG. 3 viewed from arrow A. In FIG. 4, reference numeral 17 indicates a roller holding member. The roller holding member 17 holds a roller 16 through which a shaft 16 is passed. Reference numeral 18 is a pipe which is press-fit into a take-up side boat 10 and into which the tip of the shaft 16 is inserted.
FIG. 5 is a partial cross-sectional view of FIG. 4 viewed in a direction indicated by arrow B. In FIG. 5, the shaft 16 is pressed by the tip of a screw 19 engaged with a screw hole 20 provided at an end of the take-up side boat 10 toward the internal surface of the pipe 18 (reference surface), so that the shaft 16 does not spontaneously rotate. In order to fix securely the shaft 16 to the reference surface n with the tip of the screw 19, the shaft 16 is extended to some extent below a point to which the tip of the screw 19 is pressed. In this case, the pipe 18 is extended a length of h below the bottom surface of the take-up side boat 10. With this reference surface n, the inclination of the roller post with respect to the reference surface of the take-up side boat 10 is determined, so that a very high degree of dimensional precision is required for the pipe 18.
As described above, in conventional mechanisms, the height of a roller post is generally adjusted by shifting the roller post up and down in the following manner. A roller holding member 17 is rotated so that a screw 19 provided at an end of the shaft 16 integrated with the roller holding member 17 is engaged with a screw provided in the pipe 18 integrated with a take-up boat 10.
However, there are the following problems with the above-described conventional structures.
As to the positioning mechanism described in the above-described Japanese Laid-Open Publication No. 4-318361, the boats 39 and 40 are positioned with respect to the chassis 1 so that the position and inclination of the roller post are determined. For this reason, the position of the roller post with respect to each boat and the inclination of the roller post with respect to the reference surface of each post need to be secured with great precision. To this end, each boat needs to have an accurate and complicated shape and is therefore very expensive.
As to the roller post height adjusting mechanism as described in the above-described Japanese Laid-Open Publication No. 4-318356, screws need to be formed in particular components, such as the roller post holding member 17 and the pipe 18. Not only the number of parts is increased, but also the cost of each component is increased.
As described in this publication, the pipe 18 is press-fit onto the take-up side boat 10. A shaft 16 of the roller post is provided inside the pipe 18 with reference to the reference surface n so that the inclination of the roller post is determined. Thus, the inclination of the roller post is determined via a number of components. Therefore, in order to secure the inclination precision of the roller post with respect to the chassis 1, the precision of each component needs to be greatly secured, resulting in an increase in the costs of the components.
If the inclination precision and position of the roller post depart from that intended with respect to the boat, the running of a tape immediately incurs problems, which may cause damage in the tape. As described above, in the conventional loading mechanism, the number of components is large and a high degree of precision is required for each component. Thus, cost reduction of the mechanism is prevented and it is difficult to achieve quality of the tape loading apparatus.
According to one aspect of the present invention, a tape loading apparatus comprises a base, a roller post about which a tape is wrapped for tape loading, and a carrying member for carrying the roller post. The roller post includes a rotation shaft and a roller rotating about the rotation shaft, and a shaft engagement member is provided on the base for holding the roller post at a predetermined position, the shaft engagement member directly contacting and pressing one or both ends of the rotation shaft. Therefore, a simple mechanism for positioning a roller post can be made of inexpensive components, and the number of components can be reduced, thereby providing an inexpensive and highly reliable tape loading apparatus.
In one embodiment of this invention, at least one V-shaped cut is provided in the shaft engagement member, and the at least one V-shaped cut engage a respective end of the rotation shaft. Therefore, the roller post can be fixed at a predetermined position with great precision. A tape loading apparatus can be easily obtained using more simple and inexpensive components.
According to another aspect of the present invention, a tape loading apparatus comprises a roller post about which a tape is wrapped for tape loading, a rotation shaft about which the roller post is rotatably secured, the rotation shaft having a lower portion extending from a lower end of the roller post and an upper portion extending from an upper end of the roller post, a carrier member to which the lower portion of the rotation shaft is secured, a pushing mechanism for pushing on the carrier member to move the carrier member generally horizontally for tape loading, a lower member extending toward the roller post, the lower member including a lower engagement surface for securely engaging the lower portion of the rotation shaft at a lower portion fixed horizontal position as a result of force exerted by the pushing mechanism, an upper member extending toward the roller post, the upper member including an upper engagement surface for securely engaging the upper portion of the rotation shaft at an upper portion fixed horizontal position as a result of the force exerted by the pushing mechanism, and a ceiling member including a ceiling engagement surface for securely engaging a tip of the upper portion of the rotation shaft at an upper ceiling fixed vertical position as a result of the force exerted by the pushing mechanism.
In one embodiment of this invention, the lower member and the upper member each include a V-shaped cut to form the lower and upper engagement surfaces.
In one embodiment of this invention, the lower member, upper member and ceiling member are formed by a single integral structure.
In one embodiment of this invention, the lower member, upper member and ceiling member are generally parallel to one another.
Thus, the invention described herein makes possible the advantages of providing a tape loading apparatus having a loading mechanism comprising a small number of simple components. Cost can thereby be reduced while a high level of performance is achieved.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.

Matsushita Electric Industrial Co., Ltd.


In one embodiment, a network device includes an interface to receive packets from sources in a network for forwarding to destinations in the network, the sources and destinations being assigned to groups, each packet including a source and destination identifier, a memory configured to store a source-group mapping table that maps source identifiers to source-groups, a destination-group mapping table that maps destination identifiers to destination-groups, and an intergroup access-control list that maps source-destination-group pairs to forwarding rules, and a single IC chip configured, for each packet, to find a source-group for the source identifier in the source-group mapping table, find a destination-group for the destination identifier in the destination-group mapping table, find a forwarding rule for a source-destination pair including the found source and destination-group in the intergroup access-control list, and forward or drop the packet according to the found forwarding rule.

In modern private networks, such as data centers and intracompany networks, the infrastructure may be shared across multiple users and/or tenants. In situations where the network infrastructure is being shared there are various administrative and security concerns that need to be addressed to ensure virtual infrastructure segmentation. Segmentation is certainly relevant for different enterprises but even within the same enterprise segmentation may be desirable for administrative and security reasons.
U.S. Pat. No. 9,237,158 to Smith describes a method and apparatus for providing network security using role-based access control. A network device implementing such a method can include, for example, an access control list. Such an access control list includes an access control list entry, which, in turn, includes a user group field. Alternatively, a network device implementing Such a method can include, for example, a forwarding table that includes a plurality of forwarding table entries. In such a case, at least one of the forwarding table entries includes a user group field.

Efficient implementation of complex network segmentation


Embodiments of the present disclosure disclose a machine learning training method and a server. The method includes: acquiring training data uploaded by the terminal; creating a trusted execution environment in response to a machine learning training request from the terminal; and performing machine learning training based on the trusted execution environment and the training data.

Machine learning can utilize data and experience to improve computer algorithms and is applied to many fields, such as data mining, natural language processing, speech recognition and robotics. With the development of Internet and artificial intelligence, machine learning has become a further popular subject.
Training models through machine learning requires the use of a large amount of sample data, which is typically from enterprises or users and often involves private data. Therefore, how to ensure that the private data will not be maliciously revealed in a model training process becomes an urgent problem. Furthermore, when training with privacy data from multiple data providers, it is also desirable to ensure that the privacy data from one party will not be acquired by another one.

Machine learning training method, controller, device, server, terminal and medium

BAIDU ONLINE NETWORK TECHNOLOGY (BEIJING) CO., LTD.


The method provides a uniform low-stress single crystal in a predetermined crystal orientation. The method of making it includes immersing a single crystal held at a temperature under its melting point in a melt of crystal raw material and drawing it from the melt to grow the crystal. The crystal and/or melt are rotated relative to each other during the crystal growth. A planar phase boundary surface is maintained by detecting at least one characteristic surface temperature in an interior of a crucible containing the melt and controlling temperature fluctuations by increasing or decreasing the rotation speed when they occur. The single crystals obtained by this method have a diameter of at least 50 mm and no visible growth strips in a fishtail pattern when a 2-mm thick sample is observed between crossed polarizers. Optical elements suitable for DUV lithography can be made from these crystals.

1. The Field of the Invention
The present invention relates to a method of making highly homogeneous low-stress single crystals with a predetermined orientation by immersing a single crystal in a melt and slowly drawing the single crystal out of the melt while crystallization is occurring, to an apparatus for performing the method of making the single crystals, and to the uses of the single crystals made by the method.
2. Related Art
The use of crystalline material for making lenses and optical elements is known. Particularly integrated circuits made by photolithography require large-volume calcium fluoride single crystals, which are permeable to short wavelength light up to a working wavelength of about 130 nm. Increasing requirements for increasingly higher integration density result in further miniaturization of structural elements and require forming increasingly smaller structures in the photolithograph processing. For these reasons immersion techniques used in microscopy have already been suggested for making computer chips. In these methods the optical element, through which the projected light from the objective passes, is dipped in an immersion liquid. In this way it is possible to increase the aperture angle and thus the resolution and the depth of focus. However the size of the actual objective aperture angle depends on the index of refraction of its terminal lens or front lens in the projection system. The index of refraction of CaF2 of 1.5 does not meet the requirements of the 32-nm technology points. Highly refractive crystals, especially oxides of rare earths, such as YAG, LuAG, and GGG (Gadolinium-Gallium-Garnet), which all have an index of refraction greater than 1.75, are generally used for those applications. These types of crystals are economical crystals used for making laser rods. When they are used for making laser rods, they are doped during the growing process. Laser rods with a maximum 10 mm diameter are drilled out from low-stress regions of the drawn crystals. Since these laser rods have the above-described reduced dimensions, crystal diameters of about 50 mm have already been obtained. These dimensions are essentially too small for making lens blanks for projection objectives of a stepper and their optical quality (index of refraction uniformity, stress birefringence, DUV transmission) is completely unsatisfactory.
The making of this sort of crystal generally occurs by drawing or by dipping a crystal seed in a melt of crystal raw material and by slowly drawing the crystal seed from the melt while crystallizing to form the solid crystal. The so-called Czochralski method, with which single crystals of high melting oxides, such as sapphire (Al2O3), garnet, YAG (Y3Al5O12), and spinel (MgAl2O4) are made, is usually used in industrial scale production. The crystals made in commercially available apparatus are drawn from iridium crucibles at melting temperatures up to 2000° C.
Up to now however this technology cannot produce crystals that meet the requirements for optical elements in lithography steppers. These optical elements must have diameters of at least 100 mm, especially 150 to 200 mm and, at the same time, the required optical uniformity parameters, such as a stress-induced birefringence of less than 1 nm/cm at 193 nm and an index of refraction uniformity of Δn less than 1 ppm.
If grown crystals are used for the above-described application in photolithography, they must have diameters of up to about 200 nm or larger and the required optical uniformity properties over at least 80% of the crystal diameter and at least 100 mm of the cylindrical product crystal. Only then may e.g. lens blanks with a diameter of about 150 mm and a thickness of about 40 mm be made from the grown crystals. Furthermore this sort of crystal must be economical and must have reproducible quality.
Usually a convex growth cone, which extends into the melt, arises in a growing crystal during growth of the crystal from an oxidic melt according to the Czochralski method or a method derived from it, such as the so-called "Top Speed Solution Growth Method" (TSSG). This cone arises, above all, because the energies released during crystallization is conducted away by the crystal. The curvature of the growing face of the crystal depends on the thermal properties of the crystal and the melt and their interaction.
Now it is known that the convection flow in the melt present in the crucible is poor, so that heating by means of a heating element arranged on or in the crucible wall produces a free or basic convection. The melt heated at the crucible wall rises and the slightly cooler melt in the center of the crucible sinks downward. A circular, rotationally symmetric free convection from the outside to the inside is produced in this way. On the other hand, the upper part of the melt is rotated together with the rotating crystal extending into the melt, so that the denser melt cooled at the crystal is conducted by the centrifugal forces to the crucible wall and sinks there until captured by the free convection flow and again conducted to the center of the crucible. Thus the rotating crystal produces a forced convection, which behaves in an opposite manner to the above-described free convection produced by heating. The forced and free convection are approximately mirror symmetric to each other in relation to the planar crucible cross-section.
However these opposing flow and convection processes are unstable and especially easily changed by changing the temperature profile in the crucible or the rotation speed. The resulting fluctuations and/or instabilities of the temperature act directly on the growth process at the phase boundaries between the crystal and melt and bring about fluctuations in the growth speed, which produce troublesome contrasting strips (growth strips or striations) in the finished crystal. Such contrast strips are produced by fluctuations of the lattice constants and thus the index of refraction. They impair the optical uniformity of the crystal. They are observable without more by known observation methods, such as examination between crossed polarizers or X-ray methods.
It has now been shown that the condensation heat released by condensation at the phase boundary surface produces temperature oscillations and thus the undesirable growth strips, which are still observable in the finished crystal. If a crystal of this sort is cut along its center axis, then a fishtail pattern produced by so-called striations produced by temperature fluctuations of any sort, is visible, especially in observation between crossed polarizers. If an optical element, such as a lens, is made from this sort of crystal, then it has a ring-like arrangement of differing refractive indexes similar to the growth rings of a tree. Thus a lens of this type is no longer useable for the above-described application. These types of structure defects characterized as growth strips arise themselves in unitary systems, in which distribution inhomogeneities do not occur. However it has been shown that this strip formation arises by changes and/or fluctuations in the growth conditions, especially the growing speed, which are ascribed to changes in the growing speed v and the hypothetical diffusion boundary layer thickness, δ, wherein the diffusion coefficient is a constant. These striations are formed by complex, currently not understood fluctuations in the growing speed and the transport processes at the growth front.
Currently it is not possible to keep the behavior of the convection reproducible over the entire growth period due to the competition between natural convention and forced convection. If natural convection dominates the convection processes, a convex phase boundary arises with the development of growth facets and a tendency to form growth strips. If forced convection dominates the convection processes, an especially undesirable concave phase boundary arises with all the negative effects of growth defects.
The current control methods for drawing speed, rotation speed, and optionally heating power depending on the crystal weight, which are practiced according to the state of the art, have not been sufficient for that purpose.
Many experiments for improving the uniformity of the crystals that have been grown have already been undertaken. Thus DD 290 921 described improvements in the uniformity of the garnet crystals made according to the Czocharalski method, when they are grown so that the phase boundary surface has an inclination angle, relative to the crystallographic (111) plane of 44±5° or 0±10° C. This phase boundary inclination angle is kept constant during the growing process by variation of the rotation speed.
DE 390 59 66 A1 describes growth of crystals for laser applications according to the Czochralski method, and of course especially of Nd:YAG crystals in the crystallographic (100)-direction or (111)-direction , in which the inclination angle of the phase boundary surface should be less than or equal to 35° for the (100)-direction and 44±5° for the (111)-direction . Here also the inclination angle should be maintained constant by variation of the rotation speed, once it is set. This procedure was selected, since all attempts to adjust a planar phase boundary were viewed as clever in the state of the art at that time, since the course of the phase boundary could not be reproducibly adjusted. Although this method already produces improvements in the uniformity properties of the crystals, the crystals still do not have the uniformity required for optical elements.

Method and apparatus for making a highly uniform low-stress single crystal by drawing from a melt and uses of said crystal


A layered chip package includes a main body and wiring. The main body includes a main part including a plurality of stacked layer portions, and a plurality of terminals disposed on the top and bottom surfaces of the main part. The wiring includes a plurality of lines electrically connected to the plurality of terminals. The plurality of lines include a plurality of common lines and a plurality of layer-dependent lines. Each of the plurality of layer portions includes: a plurality of common electrodes electrically connected to the plurality of common lines; a plurality of non-contact electrodes that are electrically connected to the layer-dependent lines and are not in contact with the semiconductor chip in the layer portion; and a selective connection electrode selectively electrically connected to only the layer-dependent line that the layer portion uses among the plurality of layer-dependent lines. The layer-dependent lines are greater than the common lines in maximum width.

1. Field of the Invention
The present invention relates to a layered chip package including a plurality of semiconductor chips stacked, and to a method of manufacturing the same.
2. Description of Related Art
In recent years, lighter weight and higher performance have been demanded of portable devices typified by cellular phones and notebook personal computers. Accordingly, there has been a need for higher integration of electronic components for use in the portable devices. With the development of image- and video-related equipment such as digital cameras and video recorders, semiconductor memories of larger capacity and higher integration have also been demanded.
As an example of highly integrated electronic components, a system-in-package (hereinafter referred to as SiP), especially an SiP utilizing a three-dimensional packaging technology for stacking a plurality of semiconductor chips, has attracting attention in recent years. In the present application, a package including a plurality of semiconductor chips (hereinafter, also simply referred to as chips) that are stacked is called a layered chip package. Since the layered chip package allows a reduction in wiring length, it provides the advantage of allowing quick circuit operation and a reduced stray capacitance of the wiring, as well as the advantage of allowing higher integration.
Major examples of the three-dimensional packaging technology for fabricating a layered chip package include a wire bonding method and a through electrode method. The wire bonding method stacks a plurality of chips on a substrate and connects a plurality of electrodes formed on each chip to external connecting terminals formed on the substrate by wire bonding. The through electrode method forms a plurality of through electrodes in each of chips to be stacked and wires the chips together by using the through electrodes.
The wire bonding method has the problem that it is difficult to reduce the distance between the electrodes so as to avoid contact between the wires, and the problem that the high resistances of the wires hamper quick circuit operation.
U.S. Pat. No. 5,953,588 discloses a method of manufacturing a layered chip package as described below. In the method, a plurality of chips cut out from a processed wafer are embedded into an embedding resin and then a plurality of leads are formed to be connected to each chip, whereby a structure called a neo-wafer is fabricated. Next, the neo-wafer is diced into a plurality of structures each called a neo-chip. Each neo-chip includes one or more chips, resin surrounding the chip(s), and a plurality of leads. The plurality of leads connected to each chip have their respective end faces exposed in a side surface of the neo-chip. Next, a plurality of types of neo-chips are laminated into a stack. In the stack, the respective end faces of the plurality of leads connected to the chips of each layer are exposed in the same side surface of the stack.
Keith D. Gann, "Neo-Stacking Technology", HDI Magazine, December 1999, discloses fabricating a stack by the same method as that disclosed in U.S. Pat. No. 5,953,588, and forming wiring on two side surfaces of the stack.
U.S. Pat. No. 7,127,807 B2 discloses a multilayer module formed by stacking a plurality of active layers each including a flexible polymer substrate with at least one electronic element and a plurality of electrically-conductive traces formed within the substrate. U.S. Pat. No. 7,127,807 B2 further discloses a manufacturing method for the multilayer module as described below. In the manufacturing method, a module array stack is fabricated by stacking a plurality of module arrays each of which includes a plurality of multilayer modules arranged in two orthogonal directions. The module array stack is then cut into a module stack which is a stack of a plurality of multilayer modules. Next, a plurality of electrically-conductive lines are formed on the respective side surfaces of the plurality of multilayer modules included in the module stack. The module stack is then separated from each other into individual multilayer modules.
For a wafer to be cut into a plurality of chips, the yield of the chips, that is, the rate of conforming chips with respect to all chips obtained from the wafer, is 90% to 99% in many cases. Since a layered chip package includes a plurality of chips, the rate of layered chip packages in which all of the plurality of chips are conforming is lower than the yield of the chips. The larger the number of chips included in each layered chip package, the lower the rate of layered chip packages in which all of the chips are conforming.
A case will now be considered where a memory device such as a flash memory is formed using a layered chip package. For a memory device such as a flash memory, a redundancy technique of replacing a defective column of memory cells with a redundant column of memory cells is typically employed so that the memory device can normally function even when some memory cells are defective. The redundancy technique can also be employed in the case of forming a memory device using a layered chip package. This makes it possible that, even if some of memory cells included in any chip are defective, the memory device can normally function while using the chip including the defective memory cells. Suppose, however, that a chip including a control circuit and a plurality of memory cells has become defective due to, for example, a wiring failure of the control circuit, and the chip cannot function normally even by employing the redundancy technique. In such a case, the defective chip is no longer usable. While the defective chip can be replaced with a conforming one, it increases the cost for the layered chip package.
U.S. Patent Application Publication No. 2007/0165461 A1 discloses a technique of identifying one or more defective flash memory dies in a flash memory device having a plurality of flash memory dies, and disabling memory access operations to each identified die.
In the case of forming a memory device using a layered chip package, one or more defective chips included in the layered chip package may be identified and access to such defective chips may be disabled in the same way as the technique disclosed in U.S. Patent Application Publication No. 2007/0165461 A1.
Disabling access to a defective chip in a layered chip package, however, gives rise to the following two problems. A first problem is that the defective chip is electrically connected to a plurality of terminals of the layered chip package by wiring, and such a connection can possibly cause malfunction of the layered chip package.
A second problem is that, for a layered chip package that includes a predetermined number of chips and is able to implement a memory device having a desired memory capacity when all the chips included in the layered chip package are conforming, simply disabling access to any defective chip included in the layered chip package is not sufficient for implementing the memory device having the desired memory capacity.

Layered chip package and method of manufacturing same


A locking apparatus for a standard two or three prong electrical plug connector assembly which includes a retro-fit face plate for attachment to the male plug end of the electrical connector assembly and a rotatable sleeve housing for jacketing a portion of the female socket end of the electrical connector assembly. The face plate includes a plurality of male threads provided along an outer perimeter edge thereof which threadingly engage a coordinate plurality of grooves provided to an inner wall of the sleeve housing adjacent a male plug receiving end to twist lock the two connector ends together. The sleeve housing also includes a radially inward extending notched key way at its other end which is received within a receiving slot provided to the outer periphery of the electrical outlet insulator body and which cooperates with a stop member provided to the outlet insulator body to limit lateral (rotational) travel of the sleeve housing about the outlet insulator body. In an alternate embodiment, a shortened rotatable sleeve housing is adapted for snap fit insertion within a wall-mounted electrical outlet cover plate for twist locking a male plug connector end thereto.

1. Field of the Invention
The invention relates generally to electrical connector assemblies and more particularly to a twist lock housing and face plate attachment for electrical connector assemblies of the conventional two and three prong type for preventing inadvertent separation of two mating connector ends when plugged together or inadvertent disconnection of a single male connector plug end from a receiving wall socket.
2. Brief Description of the Prior Art
In the area of electrical plug connectors, such as for example, the common two-prong or three-prong type electrical plug connectors, it is desirable to ensure that the male plug end remains connected to the female receiving socket end of an extension cord or to a receiving wall socket during use. From U.S. Pat. No. 3,891,289 issued to Hanke, a lockable electrical outlet is described wherein the electrical outlet is provided with a rotatable locking pin having a camming surface thereon and which is operative to individually close a pair of electrical contact assemblies to ensure a positive engagement with the corresponding blade contacts of an inserted male plug assembly.
A disadvantage with the rotatable locking pin arrangement of Hanke is that a finger-actuated lever portion of the rotatable locking pin member protrudes outwardly from the electrical outlet housing and, thus exposed, the lever tends to snag or hang up on fixtures or other immobile objects during use. This becomes a major inconvenience, such as for example, when a user of a power tool yanks or pulls on the extension cord and the connector assembly becomes stuck on some fixture. A stuck connector assembly means that the user must stop work and go to the site of the plug connector hang up and fix the obstruction problem. Otherwise, continued pulling on the cord may inadvertently move the exposed lever to the open position thus releasing the plug from engagement; here again, requiring the user to stop work and go to the problem area to reconnect the connector assembly and adjust the cord in an attempt to avoid further entanglements.
In the construction industry, use of extension cords for connecting power tools to a power source is wide spread. Also, the nature of the work may require moving the extension cord several times during a job, thus giving rise to the possibility that the cord will snag on stationary objects or fixtures.
Inadvertent disconnection of extension cords account for a majority of interruptions on the job. Also, locking designs of prior art electrical connectors of the type described above have not proved popular in view of the added costs and complexity associated with parts and labor in manufacture of the female socket end.
Accordingly, there is a definite need in the art for an improved low cost electrical plug locking assembly which may be implemented in an extension cord or a wall mounted outlet and which overcomes the problems of the prior art.

Locking apparatus for electrical plug connector assemblies


A content descriptor is received at a download server on a network from a remote content server, which is coupled to the download server through a computer network. The content descriptor is indicative of a selection by a user transmitted from a wireless client device to the remote content server and relating to a digital product hosted by the remote content server. The content descriptor is used by the download server to obtain the digital product from the remote content server. The digital product is then downloaded from the download server to the wireless client device via a wireless network. The content descriptor may include information such as a reference for use by the download server in locating the digital product, information describing the digital product, price information relating to the digital product, and/or information specifying a licensee of the digital product.

Personal mobile communication/computing devices, such as cellular telephones, personal digital assistants (PDAs) and two-way pagers, can be referred to collectively as "mobile devices" or "wireless devices". The current state-of-the-art of mobile devices has advanced far beyond that of their predecessors. For example, early cellular telephones used analog signals to communicate over wireless telecommunications networks (or simply "wireless networks") and were nothing more than mobile telephones. Today's most advanced cellular telephones are all digital and provide many other functions in addition to telephony capability. For example, many of the latest generation of mobile telephones (and other mobile devices) allow their users to play games, access World Wide Web pages, exchange email, exchange and download files, exchange short messaging service (SMS) messages, and send and receive video.
With new mobile devices providing a wider range of capabilities, there is increasing demand among the users of these devices (i.e., wireless services subscribers) for new and interesting types of digital content that can be used on these mobile devices, such as games and other applications, images, ring tones, screensavers, wallpapers, etc. Although newer mobile devices often come pre-provisioned with certain digital products when first acquired by the subscriber, it is desirable to allow subscribers to acquire additional digital products for use in their mobile devices, as such products become available.
Certain obstacles have thus far hindered the ability to make a wide range of digital products available to wireless subscribers. On computer networks such as the Internet, typically some computers act as servers, by providing information or services to other computers that act as the clients. Users can search for information and visit servers as they please, as long as the servers provide them with access. Each server is responsible for access control and what information it provides to whom; this is referred to as a "federated" model.
The opposite of a federated model is a so-called "walled garden" model. A network modeled after a walled garden enforces strict access control to content and information. Only the server, or servers, inside the "walls" can be accessed by users. External servers can only provide content if the content is submitted to servers inside the walls.
Service providers such as wireless Communication Service Providers (CSPs) are generally concerned with problems related to the kind of content delivered to the client devices using their networks. These problems include the following:                Quality concerns—The issue is whether the content is going to be properly consumed by the client device. If the quality is poor, the customer support issues will be costly.        Content delivery—Depending on device characteristics and content type, the delivery method to the client device may vary. Sophisticated delivery mechanisms are required to be in place with each server that intends to serve content to consumer devices.        Rights management—The issue is whether the owner of the content can be assured that only client devices with rights to the content can use the content.        Revenue—Providing content for download is a service that can be monetized (i.e., generate revenue/profit). The issue is how a CSP can ensure that the content that is downloaded is properly billed.
Since the walled garden model offers strict control over available content, it addresses the foregoing problems. However, the walled garden model has its own set of problems, including:                Consumers are restricted to the services, content and information that are available in the walled garden. This restriction can be viewed as very undesirable, especially by a consumer group that is used to the Internet.        Scalability can become a problem when all consumers access a constrained resource, such as the limited number of servers available in the walled garden.        Service management becomes critical to the CSP. If the service does not provide a compelling user experience, service use and adoption will suffer. Many CSPs do not have core expertise in this field.        Lack of choice of name-brand content may result from poor content and supplier management by the CSP.
Therefore, the basic problem becomes: How can a federated network of content servers be provided to consumers, without losing the ability to charge for content usage, manage digital rights, ensure content quality, and deliver content to client devices in a robust and secure way? Thus, it is desirable to have a solution for providing digital content to wireless devices which combines the strict control of a walled garden with the freedom provided by a federated model.

Federated download of digital content to wireless devices


A shaft hoisting plant has a conveyance and an overwind brake device for the conveyance, a travel path for the conveyance, and an overwind path adjoining a lower and/or upper end of the travel path. The overwind brake device includes retaining bars arranged in pairs in a manner spaced apart from one another and extending in a longitudinal direction, energy-absorbing material arranged in the form of plates arranged one above another in the longitudinal direction between the retaining bars. A plow is movable relative to the retaining elements, such that, upon overwinding of the conveyance, the plow deforms and/or destroys the energy-absorbing material between the retaining elements.

The invention relates to a shaft hoisting plant having a conveyance and an overwind brake device for the conveyance, a travel path, extending in a longitudinal direction, for the conveyance, and an overwind path adjoining a lower and/or upper end of the travel path.
In mining, overwinding describes the situation in which the conveyance comes to a stop only above the bank level or the upper filling station during shaft hoisting.
In shaft hoisting plants, it is possible, in the event of a defect in the control, for the conveyance to move above the upper filling station. In this case, a safety device, which acts directly on the control of the winding machine, ensures that the winding machine is stopped. The winding machine is then shut off by the limit switch and braked via the safety brake. In the event that the limit switch does not work properly or even fails entirely, a mechanical apparatus has to greatly reduce the speed of the conveyance for safety reasons. If the conveyance travels in an unbraked manner as far as under the crash beam, this can have grave consequences right up to cable breakage. Even at a low speed of a conveyance, if the conveyance travels in an unbraked manner under the crash beam, this can be associated with serious consequences for those traveling on it.
The overwind brake device, also referred to as overwind protection system, reduces the consequences of overwinding. The overwind brake device is located at the end of the shaft guide and has a device for braking, which slows down the conveyance. The braking effect may only start above the upper filling station of the conveyance and after the limit switch has been passed. The maximum deceleration of the conveyance should not exceed a value of 9.81 m/s2 for safety reasons.
In shaft hoisting plants with guide-rail guidance, guide rails that are thickened or inclined with respect to one another are used as devices for braking. The widened or pulled-together guide rails usually consist of wood. In plants with rail guidance, the devices for braking can also consist of steel.
The guide-rail thickening is embodied such that the guide rails are enlarged above and below the outermost operating position of the conveyance. This enlargement is executed symmetrically on each side of the guide rails. If a conveyance travels right into the thickened portion of the guide rails, the latter is damaged by the guide shoes arranged on the conveyance. The braking with guide-rail thickening takes place in an uncontrolled manner frequently results in the destruction of the conveyance.
Furthermore, an overwind brake device from SIEMAG TECBERG is known, in which, during braking, a braking frame having roller boxes is positively driven on flat strips. As a result of the plastic deformation of the braking strips in the roller boxes, the conveyance striking the braking frame is braked. The overwind brake device can be installed at each end of the travel path and in both winding strands. The dimensions of the flat strips are selected appropriately for the shaft hoisting plant, depending on the forces that arise. The structure of the overwind brake device from SIEMAG TECBERG is apparent from their brochure "Technische Informationen Sicherheits-Bremseinrichtung (SSA)" [Technical Information Safety Arrestor (SSA)], published at www.siemag-tecberg.com, retrieved on 06.01.2016, and from DE 10 2013 001 405 A1, paragraph [0040].
The structure of the known overwind brake device is quite complicated and therefore expensive.
DE 549 001 A discloses a shaft hoisting plant having a conveyance and an overwind brake device for the conveyance, having a travel path, extending in a longitudinal direction, for the conveyance, and an overwind path adjoining a lower and/or upper end of the travel path, referred to therein as over- and underwind zone. In the region of the overwind path, brake beams are provided, which are attached to the shaft girders or framework girders or to an auxiliary structure. Arranged on the conveyance are braking means, for example clamping tools, which come into engagement with the brake beams, which consist of any desired material, during overwinding of the conveyance.

Shaft hoisting plant having an overwind brake device


A method, apparatus, and system for an integrated solar-driven chemical plant that manages variations in solar energy are disclosed. In some embodiments, a chemical reactant, including particles of biomass, are converted in a solar driven chemical reactor into synthesis gas containing carbon monoxide and hydrogen using concentrated solar energy to drive the conversion of the chemical reactant. The synthesis gas is supplied for a catalytic conversion of the synthesis gas in a methanol synthesis plant to methanol. Cycling occurs between an operational state and an idle state for a number of methanol trains in the methanol synthesis plant depending upon an amount of synthesis gas generated in the solar driven chemical reactor. A control system for the chemical reactor sends control signals to and receives feedback from a control system for the methanol synthesis plant.

The substance/substances initially involved in a chemical reaction are generally called reactants. Chemical reactions are usually characterized by a chemical change in the reactants, which then yields one or more products. Biomass gasification is an endothermic process. Energy must be put into the endothermic process to drive the chemical reaction forward. Typically, this is performed by partially oxidizing (burning) the biomass itself. Between 30% and 40% of the biomass must be consumed to drive the process, and at the temperatures which the process is generally limited to (for efficiency reasons), conversion is typically limited, giving still lower yields. In contrast, the proposed solar-driven biorefinery uses an external source of energy (solar) to provide the energy required for reaction, so none of the biomass need be consumed to achieve the conversion. This results in significantly higher yields of gallons of gasoline per biomass ton than previous technologies. As the energy source being used to drive the conversion is renewable and carbon free. Also, chemical reactors are generally engineered to operate at constant conditions around the clock, rather than on a cyclic basis.

Systems and methods for an integrated solar driven chemical plant


A stainless steel fundamentally comprising, by weight, not more than 0.03% C, not more than 2.0% Si, not more than 5.0% Mn, 6-13% Ni, 16-21% Cr, 0.10-0.30% of N, and 0.02-0.25% Nb with the balance being Fe and inevitable impurity elements. The steel has a good corrosion resistance and a resistance to corrosion in seawater. The steel may further comprise at least one member of Mo and Cu each in an amount of not more than 0.4%, S, Se and Te each in an amount of not more than 0.08%, Bi, Pb, V, Ti, W, Ta, Hf, Zr and Al each in an amount of not more than 0.03% and P, Ca, Mg and rare earth elements each in an amount of not more than 0.01%. The steel has a recrystallized and worked double structure when subjected to a process comprising rough rolling an steel ingot at a temperature ranging from 1000.degree. to 1200.degree. C. at a working rate of not less than 50%, cooling at a cooling rate of not less then 4.degree. C./min, subsequently finish rolling at a temperature ranging from 800.degree. to 1000.degree. C. at a working rate of not less than 20%, and cooling at a cooling rate of not less than 4.degree. C./min.

1. Field of the Invention
This invention relates to austenitic stainless steels which are useful in propeller shafts, pump shafts, motor shafts all for ships and shafts for agitators and which have a high corrosion fatigue strength, loading endurance, corrosion resistance in seawater, and ductility. The present invention also relates to a method for producing such steels.
2. Description of the Prior Art
Known steels used for the propeller shafts, pump shafts and motor shafts for ships are SUS 304, SUS 316, SUS 630, and SUS 329 stainless steels (Japanese Industrial Standard). However, these steels are unsatisfactory in corrosion fatigue strength and are not satisfactory when used in an environment such as in seawater or city water where pitting corrosion is produced. For instance, SUS 304 has a corrosion fatigue strength of about 18 kgf/mm.sup.2, a pitting potential of about 280 mV and an endurance of about 27 kgf/mm.sup.2, which are low in all characteristics. SUS 316 in which 12% of Ni with 2.5% of Mo being contained has a pitting potential of about 420 mV and has thus a good resistance to corrosion in seawater, though Ni content of SUS 316 is greater than that of SUS 304, However, its corrosion fatigue strength of about 20 kgf/mm.sup.2 and endurance of about 28 kgf/mm.sup.2 are not so high. Moreover, SUS 630 in which 4.5% of Ni, 3.5% of Cu and 0.35% of Nb are contained has a good corrosion fatigue strength of about 32 kgf/mm.sup.2 and a good endurance of about 102 kgf/mm.sup.2, but its pitting potential is about 170 mV, so that the resistance to corrosion in seawater is thus poor. SUS 329 JI, which is an austenite-ferrite two-phase stainless steel composed of 25Cr-4Ni-1Mo, has a high pitting potential of about 550 mV and thus, exhibits a good resistance to corrosion in seawater, but has a low corrosion fatigue strength of about 28 kgf/mm.sup.2 and a low endurance of about 48 kgf/mm.sup.2. As will be seen from the above, the conventional stainless steels are not satisfactory with respect to all the characteristics including the corrosion fatigue strength, corrosion resistance in seawater and endurance.

Wrought stainless steel having good corrosion resistance and a good resistance to corrosion in seawater