A length-adjustable column for chairs or the like comprises an upright tube with a longitudinal axis and a piston-and-cylinder unit radially supported and displaceably guided in the direction of the longitudinal axis. A lengthwise end of the piston-and-cylinder unit is locked by an axial bearing on a base plate of the upright tube in the axial direction. For this purpose, the axial bearing is axially fixed to the lengthwise end of the piston-and-cylinder unit. The axial bearing has at least two locking arms which lock it to the base plate of the upright tube, and a securing bolt which is pushed by the piston-and-cylinder unit between the locking arms to secure the locking.

1. Field of the Invention
The invention relates to a length-adjustable column for chairs or the like, comprising an upright tube with a longitudinal axis, and a piston-and-cylinder unit received in the upright tube. A first lengthwise end of the piston-and-cylinder unit being radially supported in the upright tube and displaceably guided in the direction of the longitudinal axis, while a second lengthwise end of the piston-and-cylinder unit is locked in the axial direction by means of an axial bearing on a base plate of the upright tube having an aperture. The bearing is on the one hand fixedly connected in the axial direction to the second lengthwise end of the piston-and-cylinder unit, and on the other hand, formed with a latching arrangement which fixes the axial bearing in the axial direction on the upright tube by engagement into the aperture of its base plate.
2. Description of the Related Art
The axial bearings of such length-adjustable columns have, as indicated above, the function of fixedly connecting the second lengthwise end of the piston-and-cylinder unit to the upright tube in the direction of the longitudinal axis of the upright tube. However, it is generally desirable, especially in length-adjustable columns for swivel chairs, for the piston-and-cylinder unit to be able to rotate about the longitudinal axis of the upright tube despite being fixed in the axial direction in the upright tube. Customarily, this possibility of rotation is likewise provided by the axial bearing, or more accurately by its connection to the second lengthwise end of the piston-and-cylinder unit and/or its connection to the base plate of the upright tube.
U.S. Pat. No. 6,007,044 discloses a generic, length-adjustable column with such an axial bearing. The axial bearing, formed as an injection molding, has a fixing pin at its lower end which is intended to engage into the aperture in the base of the upright tube. The outer diameter of this fixing pin is, at its widest point, less than the inner diameter of the aperture in the base plate. A spreader ring with a frustoconical outer circumferential surface is inserted into an annular groove in the fixing pin. In its relaxed state, the spreader ring has an outer diameter that is greater than the inner diameter of the aperure of the base of the upright tube. However, when the fixing pin is introduced into that aperture, the spreader ring can be compressed to a diameter which is less than the inner diameter of the aperture of the base plate of the upright tube. If the fixing pin has passed completely through the aperture, the spreader ring expands again as a result of its intrinsic elasticity, engages behind the aperture and thus secures the axial bearing on the base plate. A disadvantage of this embodiment is that the fixing pin and the spreader ring have to be produced to close tolerances in order to be able to ensure firm seating of the axial bearing on the base plate. As a result of these narrow tolerances, however, it may occur during installation of the axial bearing that the spreader ring, after the introduction of the fixing pin into the base plate aperture, does not re-expand to the necessary extent because of excessive friction. As a result, in the event of the exertion of upward-directed axial forces away from the base plate, the axial bearing may again becomes detached from the base plate.
U.S. Pat No. 5,120,011 discloses an axial bearing, formed as a rolling contact bearing, with a cage which passes through the base of the upright tube and is locked to the piston rod. DE 21 64 196 C3 discloses a sliding bearing which is elastically locked to the piston rod. U.S. Pat. No. 4,729,458 discloses securing the locking of the piston-and-cylinder unit on the base of the upright tube by means of a separate pin introduced from below.
Additional prior art that may be mentioned for the sake of completeness includes GB 1 239 729 A, EP 0 477 617 B1, EP 0 366 889 B1, DE 1 961 656, DE-GM 67 53 661, DE-C 1 779 813 and FR 2 022 207 A.
By comparison with the above, it is an object of the invention to provide a length-adjustable column of the type mentioned initially which offers increased security against unintentional releasing of the axial bearing from the base plate of the upright tube of the column.
According to the invention, the latching arrangement has at least two locking arms and a securing bolt, the securing bolt being insertable between the locking arms in the course of production of the axially fixed connection between the axial bearing and the second lengthwise end of the piston-and-cylinder unit from this second lengthwise end of the piston-and-cylinder unit and thus securing the locking of the latching arrangement in the aperture of the base plate of the upright tube. In its position inserted between the locking arms, the securing bolt prevents the arms from moving toward one another, for example under the influence of external forces, and thus ensures that the axial bearing remains securely locked in the aperture of the base plate.
The securing bolt can be integrally molded on the axial bearing, preferably on a base disk of the axial bearing intended to rest on the base plate of the upright tube. This embodiment has the advantage that, in order to provide the complete axial bearing including all parts of the latching arrangement, only a single part needs to be manufactured. This part combines all the functions required of the axial bearing including the securing of the latching arrangement against unintentional release from the base of the upright tube. As a result of this design, moreover, preassembly steps for the axial bearing, as required for example in the axial bearing known from U.S. Pat. No. 6,007,044 in which the spreader ring has to be plug-fitted onto the fixing pin in a preassembly step, become unnecessary.
In order to enable the securing bolt to be inserted between the locking arms, in a further development of this embodiment, the securing bolt can be connected to the axial bearing, preferably the base disk thereof, via at least one predetermined breaking point. The predetermined breaking point here can be formed by a web of material connecting the securing bolt to the axial bearing, preferably the base disk thereof, and/or by a strip of material extending over at least part of the circumference of the securing bolt and connecting the securing bolt to the axial bearing, preferably the base disk thereof.
In order to prevent the securing bolt obstructing the insertion of the latching arrangement into the aperture in the base of the upright tube, it is further proposed that the securing bolt be arranged, in a ready-to-fit state of the axial bearing, substantially completely outside the area between the locking arms.
The locking arms may be designed in various ways: for example, at least one of the locking arms can be elastically lockable to the base plate of the upright tube. In addition, or alternatively, it is also possible for the locking arms to be spread as a result of the insertion of the securing bolt.
In order to be able to prevent unintentional dropping of the securing bolt out of the area between the locking arms, the latching arrangement may have at least one axial stop for the securing bolt. This at least one axial stop may, for example, be formed by at least one shoulder on at least one of the locking arms. In addition, or alternatively, the securing bolt may have at least one lengthwise groove which is open at its end nearer the locking arm and closed at its end further from the locking arm in the direction of the longitudinal axis, and the axial bearing has at least one shoulder which engages into an assigned lengthwise groove.
For axially fixing the axial bearing on the second lengthwise end of the piston-and-cylinder unit, the axial bearing, preferably the base disk thereof, can be provided in a conventional manner with a snap-engagement arrangement. According to a structurally simple embodiment, this snap-engagement arrangement may have at least one snapping arm. To retain the second lengthwise end of the piston-and-cylinder unit, this at least one snapping arm may have a locking surface which is, for example, substantially trapezoidal in section and intended to engage into a locking recess provided on the circumference of the second lengthwise end of the piston-and-cylinder unit. In order to be able to provide a connection between the axial bearing and the piston-and-cylinder unit in the direction of the axis of the upright tube which is firm but allows twisting about that axis, the locking recess on the circumference of the second lengthwise end of the piston-and-cylinder unit can be a locking groove extending over the entire circumference.
To facilitate installation of the piston-and-cylinder unit into the upright tube, it is also proposed that the axial bearing comprise a cage to receive, preferably with a friction fit, the second lengthwise end of the piston-and-cylinder unit. This is because the cage makes it possible for the axial bearing to be plug-fitted onto the second lengthwise end of the piston-and-cylinder unit and introduced into the upright tube together with the latter. Thus, no elaborate preassembly of the axial bearing in the aperture of the base of the upright tube is necessary. Instead, the axial bearing can be installed together with the piston-and-cylinder unit.
The cage may, for example, have a holding ring which is connected to a base disk of the axial bearing via at least one connecting web. At least one elongate projection extending in the axial direction can be provided on an inner surface of the holding ring and/or of the at least one connecting web. This at least one projection serves to rest on the second lengthwise end of the piston-and-cylinder unit and, because of its relatively small contact surface with the latter, prevents the occurrence of excessive frictional forces between piston-and-cylinder unit and axial bearing even when production tolerances are generous.
In principle, it is possible for the at least one above-mentioned snapping arm of the snap-engagement arrangement to start from the base disk of the axial bearing. According to the invention, however, the at least one snapping arm extends from the holding ring toward the base disk.
As is known per se, the second lengthwise end of the piston-and-cylinder unit can be formed by the free end of a piston rod of this piston-and-cylinder unit. In order to be able to prevent the piston rod breaking through the base of the upright tube in the serious event of destruction of the axial bearing, it is proposed that the piston rod have a greater diameter than the aperture in the base of the upright tube.
From another standpoint, the invention relates to an axial bearing having the axial bearing features explained above.
Finally, the invention also relates to a method for installing a piston-and-cylinder unit in an upright tube of a length-adjustable column for chairs or the like, using an axial bearing according to the invention. The installation method according to the invention comprises the following steps:
plug-fitting the axial bearing with its cage onto the second lengthwise end of the piston-and-cylinder unit,
introducing the piston-and-cylinder unit preassembled in this way into the upright tube with the second lengthwise end foremost,
exerting a first axial installing force on the piston-and-cylinder unit, which is sufficient to introduce the latching arrangement sufficiently far into the aperture in the base plate of the upright tube for the axial bearing to rest on the base plate, and
exerting a second axial installing force on the piston-and-cylinder unit which is greater than the first installing force and which is sufficient to introduce the securing bolt between the locking arms of the latching arrangement.
Advantageously, the second axial installation force can be such as to suffice to destroy the predetermined breaking points by means of which the securing bolt is retained on the axial bearing.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Length adjustable column with axial bearing, and method of installation of the axial bearing


According to one general aspect, an apparatus may include an instruction fetch unit, an execution unit, and a cache resynchronization predictor, as described above. The instruction fetch unit may be configured to issue a first memory read operation to a memory address, and a first memory write operation to the memory address, wherein the first memory read operation is stored at an instruction address. The execution unit may be configured to execute the first memory read operation, wherein the execution of the first memory read operation causes a resynchronization exception. The cache resynchronization predictor may be configured to associate the instruction address with a resynchronization exception, and determine if a memory read operation stored at the instruction address comprises a resynchronization predicted store.

Processors or computing systems generally make use of pipelined architectures. In computing, a pipeline is often a set of data processing elements (e.g., execution units, functional unit blocks (FUBs), combinatorial logic blocks (CLBs), etc.) connected in series, where the output of one element or pipeline stage is the input of the next pipeline stage. The stages of a pipeline are often executed in parallel or in time-sliced fashion. This generally allows a computer to execute several instructions substantially in parallel or in near-parallel, as a second instruction may be started in the first pipeline stage as soon as the first instruction has exited that first pipeline stage, despite the first instruction not being fully completed or done all the pipeline stages. This pseudo-parallelism greatly increases the speed at which a group of instructions may complete, despite the instructions' dependence upon each other (e.g., the second instruction may rely upon the result of the first instruction, etc.).
Further, many instructions involve the reading (load) or writing (store) of data from a memory. Often the data is stored in a cache system. A computer's cache system is generally a tiered system of increasingly smaller but faster memory components that each store a sub-set of the data stored in the larger but slower next tier. If the desired piece of data is found in the smallest, fastest cache the instruction completes without incident. However, if the data is not in the sub-set stored in the smallest, fastest cache, the data must be retrieved from the next tier in the system (and so on) and this often causes delays and other complications.
Processors commonly rely on performing load (read) and store (write) instructions out of order to achieve higher performance. If the load and stores are to different memory addresses (i.e. for different pieces of data), this may occur without problems and may speed the overall execution of the program executed by the processor.
However, occasionally when a younger load (read) instruction is executed before an older store (write) instruction to the same memory address, the load (read) may return incorrect or out-of-date data. This is generally known as a pipeline hazard or more specifically a Read-After-Write (RAW) hazard. Generally, when this occurs, processors need to repair the bad load data by performing a costly RAW resynchronization exception (RRE). Often in order to repair this, all in-process instructions younger than the store (write) are flushed from the processor's pipeline (i.e. all the work done on any instructions after the store, including the load, is discarded). All of the instructions after the store are then restarted, as the work previously performed on them was incorrect or suspect. This event is frequently costly due to the extra clock cycles it takes to flush or discard instructions, re-fetch or re-start them, and then re-perform them. This is often referred to as the RRE penalty.

Method and apparatus for handling processor read-after-write hazards with cache misses


A network security module for protecting computing devices connected to a communication network from identified security threats communicated in a secured communication is presented. The network security module is interposed, either logically or physically, between the protected computer and the communication network. Upon detecting a secured communication, the network security module obtains a decryption key from the computing device to decrypt the secured communication. The network security module then processes the decrypted communication according to whether the decrypted communication violates protective security measures implemented by the network security module.

As more and more computers, and other computing devices, are inter-connected through various networks, such as the Internet, computer security has become increasingly more important, particularly from invasions or attacks delivered over a network or over an information stream. As those skilled in the art will recognize, these attacks come in many different forms, including, but certainly not limited to, computer viruses, computer worms, system component replacements, denial of service attacks, even misuse/abuse of legitimate computer system features, all of which exploit one or more computer system vulnerabilities for illegitimate purposes. While those skilled in the art will realize that the various computer attacks are technically distinct from one another, for purposes of the present invention and for simplicity in description, all of these attacks will be generally referred to hereafter as computer exploits, or more simply, exploits.
When a computer system is attacked or "infected" by a computer exploit, the adverse results are varied, including disabling system devices; erasing or corrupting firmware, applications, or data files; transmitting potentially sensitive data to another location on the network; shutting down the computer system; or causing the computer system to crash. Yet another pernicious aspect of many, though not all, computer exploits is that an infected computer system is used to infect other computers.
FIG. 1 is a pictorial diagram illustrating an exemplary networked environment 100 over which a computer exploit is commonly distributed. As shown in FIG. 1, the typical exemplary networked environment 100 includes a plurality of computers 102-108 all inter-connected via a communication network 110, such as an intranet or via a larger communication network including the global TCP/IP network commonly referred to as the Internet. For whatever reason, a malicious party on a computer connected to the network 110, such as computer 102, develops a computer exploit 112 and releases it on the network. The released computer exploit 112 is received by, and infects, one or more computers, such as computer 104, as indicated by arrow 114. As is typical with many computer exploits, once infected, computer 104 is used to infect other computers, such as computer 106 as indicated by arrow 116, which in turn infects yet other computers, such as computer 108 as indicated by arrow 118. Clearly, due to the speed and reach of the modern computer networks, a computer exploit 112 can "grow" at an exponential rate, and quickly become a local epidemic that quickly escalates into a global computer pandemic.
A traditional defense against computer exploits, and particularly computer viruses and worms, is anti-virus software. Generally, anti-virus software scans incoming data, arriving over a network, looking for identifiable patterns associated with known computer exploits. Upon detecting a pattern associated with a known computer exploit, the anti-virus software may respond by removing the computer virus from the infected data, quarantining the data, or deleting the "infected" incoming data. Unfortunately, anti-virus software typically works with "known," identifiable computer exploits. Frequently, this is done by matching patterns within the data to what is referred to as a "signature" of the exploit. One of the core deficiencies in this exploit detection model is that an unknown computer exploit may propagate unchecked in a network until a computer's anti-virus software is updated to identify and respond to the new computer exploit.
As anti-virus software has become more sophisticated and efficient at recognizing thousands of known computer exploits, so too have the computer exploits become more sophisticated. For example, many recent computer exploits are now polymorphic, or in other words, have no identifiable pattern or "signature" by which they can be recognized by anti-virus software in transit. These polymorphic exploits are frequently unrecognizable by anti-virus software because they modify themselves before propagating to another computer system.
Another defense that is common today in protecting against computer exploits is a hardware or software network firewall. As those skilled in the art will recognize, a firewall is a security system that protects an internal network from unauthorized access originating from external networks by controlling the flow of information between the internal network and the external networks. All communications originating outside of the firewall are first sent to a proxy that examines the communication, and determines whether it is safe or permissible to forward the communication to the intended target. Unfortunately, properly configuring a firewall so that permissible network activities are uninhibited and that impermissible network activities are denied is a sophisticated and complicated task. In addition to being technically complex, a firewall configuration is difficult to manage. When firewalls are improperly configured, permissible network traffic may be inadvertently shut down and impermissible network traffic may be allowed through, compromising the internal network. For this reason, changes to firewalls are generally made infrequently, and only by those well versed in the subject of technical network design.
As yet a further limitation of firewalls, while a firewall protects an internal network, it does not provide any protection for specific computers. In other words, a firewall does not adapt itself to a specific computer's needs. Instead, even if a firewall is used to protect a single computer, it still protects that computer according to the firewall's configuration, not according to the single computer's configuration.
Yet another issue related to firewalls is that they do not provide protection from computer exploits originating within the borders established by a firewall. In other words, once an exploit is able to penetrate the network protected by a firewall, the exploit is uninhibited by the firewall. This situation frequently arises when an employee takes a portable computer home (i.e., outside of the corporate firewall protection) and uses it at home in a less secured environment. Unknown to the employee, the portable computer is then infected. When the portable computer is reconnected to the corporate network within the protection of the firewall, the exploit is often free to infect other computers unchecked by the firewall.
As mentioned above, computer exploits now also leverage legitimate computer system features in an attack. Thus, many parties other than firewall and anti-virus software providers must now join in defending computers from these computer exploits. For example, operating system providers must now, for economic and contractual reasons, continually analyze their operating system functions to identify weaknesses or vulnerabilities that may be used by a computer exploit. For purposes of the present discussion, any avenue by which a computer exploit may attack a computer system will be generally referred to as a computer system vulnerability, or simply a vulnerability.
As vulnerabilities are identified and addressed in an operating system, or other computer system components, drivers, applications, the provider will typically release a software update to remedy the vulnerability. These updates, frequently referred to as patches, should be installed on a computer system in order to secure the computer system from the identified vulnerabilities. However, these updates are, in essence, code changes to components of the operating system, device drivers, or software applications. As such, they cannot be released as rapidly and freely as anti-virus updates from anti-virus software providers. Because these updates are code changes, the software updates require substantial in-house testing prior to being released to the public. Unfortunately, even with in-house testing, a software update may cause one or more other computer system features to break or malfunction. Thus, software updates create a huge dilemma to parties that rely upon the computer systems. More specifically, does a party update their computer systems to protect them from the vulnerability and risk disrupting their computer systems' operations, or does the party refrain from updating their computer systems and run the risk that their computer systems may be infected?
Under the present system, there is a period of time, referred to hereafter as a vulnerability window, that exists between when a new computer exploit is released on the network 110 and when a computer system is updated to protect it from the computer exploit. As the name suggests, it is during this vulnerability window that a computer system is vulnerable, or exposed, to the new computer exploit. FIGS. 2A-2B are block diagrams of exemplary timelines illustrating this vulnerability window. In regard to the following discussions regarding timelines, significant times or events will be identified and referred to as events in regard to a timeline.
FIG. 2A illustrates a vulnerability window of computer systems with regard to one of the more recent, sophisticated class of computer exploits that are now being released on public networks. As will be described below, this new class of computer exploits take advantage of a system provider's proactive security measures to identify computer system vulnerabilities, and subsequently, create and deliver a computer exploit.
With reference to FIG. 2A, at event 202, an operating system provider identifies the presence of a vulnerability in the released operating system. For example, in one scenario, the operating system provider, performing its own internal analysis of a released operating system, uncovers a previously unknown vulnerability that could be used to attack a computer system. In an alternative scenario, the previously unknown vulnerability is discovered by third parties, including organizations that perform system security analyses on computer systems, and relays information regarding the vulnerability to the operating system provider.
Once the operating system provider is aware of the presence of the security vulnerability, the operating system provider addresses the vulnerability which, at event 204, leads to the creation and release of a patch to secure any computer systems running the operating system. Typically, an operating system provider will make some type of announcement that there is a system patch available, along with a recommendation to all operating system users to install the patch. The patch is usually placed in a known location on the network 110 for downloading and installation onto affected computer systems.
Unfortunately, as happens all too often, after the operating system provider releases the patch, at event 206, a malicious party downloads the patch and, using some reverse engineering as well as any information made public by the operating system or others, identifies the specifics regarding the "fixed" vulnerability in the operating system. Using this information, the malicious party creates a computer exploit to attack the underlying vulnerability. At event 208, the malicious party releases the computer exploit onto the network 110. While the goal of issuing a software patch, also known as a "fix," is to correct an underlying vulnerability, the "fix" is often a complex piece of software code which itself, unfortunately, may create or contain a new vulnerability that could be attacked by a computer exploit created by a malicious party. Thus, in addition to evaluating what the "fix" corrects, the "fix" is also evaluated for potential vulnerabilities.
While a "fix" is available, the malicious party realizes that, for various reasons including those described above, not every vulnerable computer system will be immediately upgraded. Thus, at event 208, the malicious party releases the computer exploit 112 onto the network 110. The release of the computer exploit 112 opens a vulnerability window 212, as described above, in which the vulnerable computer systems are susceptible to this computer exploit. Only when the patch is finally installed on a computer system, at event 210, is the vulnerability window 212 closed for that computer system.
While many computer exploits released today are based on known vulnerabilities, such as in the scenario described in regard to FIG. 2A, occasionally, a computer exploit is released on the network 110 that takes advantage of a previously unknown vulnerability. FIG. 2B illustrates a vulnerability window 230 with regard to a timeline 220 under this scenario. Thus, as shown on timeline 220, at event 222, a malicious party releases a new computer exploit. As this is a new computer exploit, there is neither an operating system patch nor an anti-virus update available to protect vulnerable computer systems from the attack. Correspondingly, the vulnerability window 230 is opened.
At some point after the new computer exploit is circulating on the network 110, the operating system provider and/or the anti-virus software provider detects the new computer exploit, as indicated by event 224. As those skilled in the art will appreciate, typically, the presence of the new computer exploit is detected within a matter of hours by both the operating system provider and the anti-virus software provider.
Once the computer exploit is detected, the anti-virus software provider can begin its process to identify a pattern, or "signature," by which the anti-virus software may recognize the computer exploit. Similarly, the operating system provider begins its process to analyze the computer exploit to determine whether the operating system must be patched to protect it from the computer exploit. As a result of these parallel efforts, at event 226, the operating system provider and/or the anti-virus software provider releases an update, i.e., a software patch to the operating system or an anti-virus update, which addresses the computer exploit. Subsequently, at event 228, the update is installed on a user's computer system, thereby protecting the computer system and bringing the vulnerability window 230 to a close.
As can be seen from the examples above, which are only representative of all of the possible scenarios in which computer exploits pose security threats to a computer system, a vulnerability window exists between the times that a computer exploit 112 is released on a network 110, and when a corresponding update is installed on a user's computer system to close the vulnerability window. Sadly, whether the vulnerability window is large or small, an infected computer costs the computer's owner substantial amounts of money to "disinfect" and repair, if it is at all possible. This cost can be enormous when dealing with large corporations or entities that may have thousands or hundreds of thousands of devices attached to a network 110. Such a cost is further amplified by the possibility that such an exploit tamper or destroys customer data, all of which may be extremely difficult or impossible to trace and remedy. What is needed is a system and method for securing a computer system against computer exploits in a responsive manner and according to the individual computer system's needs, even before a protective update is available and/or installed on the computer system. These, and other issues found in the prior art, are addressed by the present invention.

System and method for protecting a computing device from computer exploits delivered over a networked environment in a secured communication


An aspect of the present disclosure includes methods, systems, and computer-readable media for receiving a first timing reference signal and a second timing reference signal at a local device, wherein the second timing reference signal includes an internal timing reference, receiving a timing indication from a remote device, calculating a timing offset from at least one of a propagation delay, the timing indication, or the first timing reference signal, adjusting the internal timing reference based on the timing offset, and transmitting a message based on the internal timing reference.

Aspects of the present disclosure relate generally to wireless communication networks, and more particularly, to apparatus and methods for cellular vehicle-to-everything (CV2X) communication.
Wireless communication networks are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, and single-carrier frequency division multiple access (SC-FDMA) systems.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. For example, a fifth generation (5G) wireless communications technology (which may be referred to as new radio (NR)) is envisaged to expand and support diverse usage scenarios and applications with respect to current mobile network generations. In an aspect, 5G communications technology may include: enhanced mobile broadband addressing human-centric use cases for access to multimedia content, services and data; ultra-reliable-low latency communications (URLLC) with certain specifications for latency and reliability; and massive machine type communications, which may allow a very large number of connected devices and transmission of a relatively low volume of non-delay-sensitive information. As the demand for mobile broadband access continues to increase, however, further improvements in NR communications technology and beyond may be desired.
When utilizing CV2X communication, a device such as a user equipment (UE) may synchronize with other devices, such as other UEs or 5G base stations (gNBs) using one or more timing references. Depending on environmental variables, accuracy of a timing reference source, and other factors, certain timing references may be more accurate than others. Improvement in accuracy of the timing reference may improve the signal-to-noise-interference ratio (SNIR), and thus the data throughput. Therefore, it may be desirable for the device to rely on a more accurate timing reference.


Disclosed is a method of manufacturing a mask for conductive wirings in a semiconductor device, wherein the conductive wirings are formed on a semiconductor substrate of the semiconductor device, comprising the steps of: (a) calculating data for the entire regions of the semiconductor substrate on which the conductive wirings are formed; (b) reading the size, shape and position of the conductive wiring patterns for the conductive wirings to generate data for conductive wirings, and storing the generated conductive wirings data; (c) extending the conductive wirings data by a predetermined size to generate data for the extended conductive wirings; (d) subtracting the extended conductive wirings data from the data for the entire regions of the semiconductor substrate to calculate a differential data between the extended conductive wirings data and the entire regions data, and to generate data for dummy conductive wiring pattern; (e) adding the conductive wirings data to the dummy conductive wiring pattern data to form a pattern the size and position of which correspond to data obtained by the addition operation on the mask by using a clear field method.

This application claims the priority of Korean patent application Serial No. 99-46436 filed on Oct. 25, 1999.
1. Field of the Invention
The present invention relates to a method of manufacturing a mask for conductive wirings in a semiconductor device, and more particularly, a method of manufacturing a mask for conductive wirings in a semiconductor device which is adapted to more easily perform a planarization process for an interlayer insulating film formed on the upper portion of conductive wirings for interconnecting respective elements disposed on a semiconductor substrate.
2. Description of the Related Art
Currently, as the development of semiconductor devices follows a trend toward an increased capacity and a highly integrated degree, an area of the semiconductor devices becomes reduced increasingly, and consequently, a metal wiring within the semiconductor devices and the width thereof are reduced. There is therefore a need for a conductive wiring structured of several layers together with this structure.
In order to construct such a conductive wiring into several layers, and, at the same time, to minimize the size of the conductive wirings, it is necessary that an interlayer insulating film formed on the upper portion of a lower conductive wiring should be planarized. The aim of this planarization for the interlayer insulating film is to improve the depth of a focus in the process of development of a light sensitive film for patterning an upper conductive wiring. Also, such a planarization process is a requisite for depositing a film made of tungsten and performing successively a CMP (Chemical-Mechanical Polishing) process when forming a tungsten plug to bury a contact.
In the meantime, a process of manufacturing a mask for a conventional semiconductor device will be described hereinafter with respect to the present invention.
First, a layout for a circuit to be formed is designed, and the layout for the circuit is to calculate the size of a physical device generating an electrical parameter according to the formation of the circuit. In the process of this layout, the size in length of a designed drawing for a circuit determines the thickness of a layer to be deposited by CVD or to be doped, and the vertical size thereof determines the size of a wafer pattern, which become a basis for a reduced drawing of a resultant circuit called a composite drawing.
After the completion of the layout, a digitizing process is performed for determining a coordinate of a drawing in which a semiconductor circuit is designed to fabricate a mask. That is, the drawing is positioned on an X-Y board in which a cursor is connected to a computer, and the cursor reads the size, shape and position of each pattern in the drawing to store them in a memory of the computer. This information on the pattern is used for fabrication of a reticle or in an Ebeam driving system.
When such a digitizing process is completed, the pattern is copied to form a mask, which is called the reticle. This reticle is an emulsion plate or a chrome thin film selectively exposed to a light from a pattern generator (PG). The pattern generator (PG) consists of a light source and a high-speed shutter which is controlled by a computer, and the pattern is developed to form opaque and transparent areas on a surface of the reticle like a photo film development. The pattern of the reticle is transferred to a mask on which a photoresist having a uniform thin film is coated by the light source.
By using the mask fabricated through the above-mentioned processes, conductive wirings of a semiconductor device are formed. If another upper conductive wiring is formed to form a multi-layered conductive wiring, an interlayer insulating film is formed on a conductive wiring formed previously, followed by a planarization process being performed on the interlayer insulating film.
Meanwhile, in performing such a planarization process, an interval between respective conductive wirings formed in the same layer determines whether or not the planarization process will be performed successively, which will be described hereinafter with reference to FIG. 1.
FIG. 1 is a top view illustrating a mask 40 used for forming conductive wirings in a typical semiconductor device according to the prior art.
In FIG. 1, each conductive wiring pattern (chrome pattern) is formed on a conventional typical a mask 40 for conductive wirings according to the type of a conductive wiring to be formed on a glass substrate 40. Conductive wirings are formed on a semiconductor substrate through a patterning process using this mask 40.
FIG. 2A is a cross-sectional views illustrating a semiconductor device in which conductive wirings are formed using the mask 40 shown in FIG. 1, followed by forming an another interlayer insulating layer to form upper conductive wirings according to the prior art.
Referring to FIG. 2A, after a first interlayer insulating layer 52 has been formed on a top surface of the a semiconductor substrate 51, respective conductive wirings 53-1, 53-2, and 53-3 are formed on the first interlayer insulating layer 52 by using the mask 40 shown in FIG. 1. Then, a second interlayer insulating layer 54 is formed on the first interlayer insulating layer 52 and the respective conductive wirings 53-1, 53-2, and 53-3 to build a structure having the shape as shown in FIG. 2A.
In the state in which this process is completed, in order to form another upper conductive wiring on the second interlayer insulating layer 54, it is necessary that the planarization process should be performed on the second interlayer insulating layer 54.
FIG. 2B is a cross-sectional view illustrating a semiconductor device in the state in which a CMP process for the planarization is performed on the structure as shown in FIG. 2A, and the top surface of the second interlayer insulating film 54 is washed.
As shown in FIG. 2A, dishings occur on the top surfaces of the second interlayer insulating film 54 corresponding to the region between the conductive wirings 53-1 and 53-2 spaced apart at a minimum interval and the region between the conductive wirings 53-2 and 53-3 among the conductive wirings 53-1, 53-2 and 53-3, so that the planarization for the second interlayer insulating film 54 is not accomplished normally.
Furthermore, though the dishing formed corresponding to the region between the conductive wirings 53-1 and 53-2 is eliminated by the planarization process, in the case of the dishing formed corresponding to the region between the conductive wirings 53-2 and 53-3 shown in FIG. 2B, the top surface of a region of the interlayer insulating film 54 where a difference in a space between the conductive wirings is greater has a deeper step portion when compared with the top planar surface of the remaining regions of the interlayer insulating film 54. As a result, there has been a problem in that since a pad of CMP equipment is out of contact with the top surface of the region of the interlayer insulating film 54 having the deeper step formed therein, it is very difficult to achieve a complete planarization for the interlayer insulating film 54 according to the density of the conductive wirings and shape of arranged conductive wirings in a semiconductor chip (semiconductor device).
In the meantime, FIGS. 3A and 3B are cross-sectional views illustrating a semiconductor device for which another planaraization process has been performed using a separate step compensating layer in order to resolve the above conventional problem.
First, in FIG. 3A, after a first interlayer insulating film 62 has been formed on a semiconductor substrate 61, respective conductive wirings 63-1, 63-2, and 63-3 are formed thereon by using the mask 40 as shown in FIG. 1. A second interlayer insulating film 64 is then formed on the conductive wirings 63-1, 63-2, and 63-3 and the first interlayer insulating film 62 to form upper conductive wirings thereon.
After a formation of the second interlayer insulating film 64 has been completed, in order to compensate a step portion formed on the surface thereof a separate step compensating film 65 is formed in the step portion as shown in FIG. 3A prior to execution of the planarization process for the second interlayer insulating film 64.
Namely, the size of the step portion varies with the distance spaced between the respective conductive wirings 63-1, 63-2 and 63-3 in the second interlayer insulating film 64. For this reason, in order to prevent an abnormal planarization in the second interlayer insulating film 64, the step compensating film 65 is additionally formed on the step portion in a portion of the second interlayer insulating film 64 formed between the conductive wirings 63-2 and 63-3 spaced apart at a relatively large interval from each other among the conductive wirings 63-1, 63-2 and 63-3 by a separate process.
At this time, the step compensating film 65 formed on the top surface of the second interlayer insulating film 64 having the step portion is usually formed of the same material as that forming the second interlayer insulating film 64 for efficiency of the planarization process
On the other hand, when a structure having a configuration as shown in FIG. 3a through the above process is fabricated, the planarization process is conducted to form upper conductive wirings on the second interlayer insulating film 64.
FIG. 3B is a cross-sectional view illustrating a semiconductor device structure in the state in which a planaraization process for the structure shown in FIG. 3A has been completed.
That is, unlike in the case of FIGS. 2A and 2B, the planaraization process is conducted after compensating the step portion formed in the second interlayer insulating film 64 by using the step compensating film 65, thereby preventing a dishing. Owing to this, as shown FIG. 3B, a normal planarization process is completed.
As another conventional method, unlike in the case of FIGS. 3A and 3B, there is a method in which a dummy pattern is formed at the same time upon first fabrication of a mask, and a conductive wiring and a dummy wiring of a semiconductor device using this mask are formed through a single process.
However, in the case of using a conventional method of forming respective conductive wirings as described above, a defect in the planarization process as shown in FIGS. 2A and 2B can be compensated, but an additional process for forming a separate step compensating film 65 as shown in FIG. 3A, i.e., a mask process and a patterning process for forming the step compensating film 65 are added, thereby reducing productivity of the semiconductor device.
Namely, as described above, in order to form a dummy wiring additionally besides the conductive wiring, it is necessary that a dummy pattern for the dummy wiring should be further drawn on a drawing for fabrication of a reticle. In addition, the dummy pattern must also be formed additionally on a mask for forming the conductive wiring, thereby resulting in generation of a manufacturing cost of the mask and a loss of labor.
Therefore, the present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a method of manufacturing a mask for conductive wirings in a semiconductor device in which a pattern for a dummy wiring is formed to fabricate the mask by using data values for the conductive wirings without actually forming the dummy wiring pattern on a mask in forming the dummy wiring pattern between conductive wiring patterns spaced apart at a larger interval from each other during the fabrication of the mask of the semiconductor device.
According to an aspect of the present invention, there is provided a method of manufacturing a mask for conductive wirings in a semiconductor device, wherein the conductive wirings are formed on a semiconductor substrate of the semiconductor device, comprising the steps of:
(a) calculating data for the entire regions of the semiconductor substrate on which the conductive wirings are formed;
(b) reading the size, shape and position of the conductive wiring patterns for the conductive wirings to generate data for the conductive wirings, and storing the generated conductive wirings data;
(c) extending the conductive wirings data by a predetermined size to generate data for the extended conductive wirings;
(d) subtracting the extended conductive wirings data from the data for the entire regions of the semiconductor substrate to calculate a differential data between the extended conductive wirings data and the entire regions data, and to generate data for dummy conductive wiring pattern;
(e) adding the conductive wirings data to the dummy conductive wiring pattern data to form a pattern the size and position of which correspond to data obtained by the addition operation on the mask by using a clear field method.
According to another aspect of the present invention, there is also provided a method of manufacturing a mask for conductive wirings in a semiconductor device, wherein the conductive wirings are formed on a semiconductor substrate of the semiconductor device, comprising the steps of:
(a) reading the size, shape and position of the conductive wiring patterns for the conductive wirings to be formed on the silicon substrate to generate data for conductive wirings, and storing the generated conductive wirings data;
(b) extending the conductive wirings data by a predetermined size to generate data on the extended conductive wirings; and
(c) subtracting the conductive wirings data from the extended conductive wirings data to calculate a differential data between the conductive wirings data and the extended conductive wirings data, and forming a pattern the size and position of which correspond to the difference data on the mask by using a dark field method.

Method of manufacturing mask for conductive wirings in semiconductor device


A surgical method for arthroscopic repair or replacement of the anterior cruciate ligament is disclosed. A preferred embodiment of the method generally includes forming osseous tunnels in the tibia and femur, opening into the intercondylar region. A patellar tendon graft is harvested from the knee, having bone plugs naturally attached to each end. The graft is secured in the osseous tunnels by an interference fit with a bone screw inserted between the tunnel walls and the bone plugs. Specialized instrumentation for performing the method steps is also disclosed. Such instrumentation includes: a combination drill for cutting an osseous tunnel and harvesting a bone core, an intercondylar guide for locating a pilot hole on the femoral condyle, single-fluted and multi-fluted hand and power reamers for forming an osseous tunnel, and a work station for facilitating preparatory steps performed on graft material.

The basis for deficiencies of the anterior cruciate ligament ("ACL") and various techniques of repair or replacement have been known for many years. See, The Anterior Cruciate Ligament Deficient Knee, Clinical Orthopaedics and Related Research, No. 172 (January-February 1983) (J. Feagin, Jr., M. D., Guest Ed.). The great variety of techniques and the non-uniform acceptance of any single technique may have contributed to the lack of specialized instrumentation for performing replacement or repair of the ACL. Instrumentation which has become somewhat specialized in this area is drill guides for locating holes in the tibia and femur. Hewson, Drill Guides for Improving Accuracy in Anterior Cruciate Ligament Repair and Reconstruction, Clin. Orth. Rel. Res. 172: 119-124 (January-February 1983) presents a survey of various drill guides. However, none of the drill guides available are without its particular disadvantages.
One technique for the replacement of the ACL, which has gained in popularity in recent years, is the use of a graft taken from the patellar tendon and inserted into tunnels reamed in the femur and tibia. This technique is described in Lambert, Vascularized Patellar Tendon Graft with Rigid Internal Fixation for Anterior Cruciate Ligament Insufficiency, Clin. Orth. Rel. Res. 172: 85-89 (January-February 1983). In this the portion of the patellar tendon used is separated from the tibia and patella with a scalpel and osteotome. The osteotome is used to separate the graft with small pieces of bone (to serve as bone plugs) naturally attached at each end of the tendon. One problem associated with this procedure is that the osteotome creates V-shaped defects or recesses where the small bone pieces are removed. The V-shape of the defects can create high stress concentration at those points.
Tunnels or holes are drilled in the tibia and femur, both opening to the intercondylar region. Lambert teaches that the most accurate placement of the holes is achieved by drilling both holes from the outside of the bone towards the inside. Lambert also recommends the use of a Hewson intercondylar drill guide for accurate placement of the holes.
Once the holes have been formed in the tibia and femur, the graft is twisted 180.degree. and pulled through the bone holes by sutures placed through the bone plugs. The twisting of the graft is important to maintain the isometric function of the graft. The ligament graft is secured in place by interference fit of bone screws between the bone hole wall and the bone plug attached to the tendon ends. The procedure as described by Lambert is not arthroscopic.
Rosenberg, Technique for Endoscopic Method of ACL Reconstruction (Acufex Brochure 1989), describes a modification of the Lambert technique. The Rosenberg technique is arthroscopic and utilizes a femoral tunnel drilled from below the femur. Rosenberg illustrates the difficulty in locating the center of the femoral tunnel. A method for testing the location to ensure that it will provide proper isometric function of the ligament graft is disclosed, but the location must still be selected without the use of a guide to ensure placement relative to the bone mass in which the tunnel is formed. The location thus depends to a large extent on the skill of the surgeon. While specialized instrumentation is described, it is related only to the method of testing the location for isometric positioning.
Although procedures for repair of the ACL have become relatively common, without special instrumentation, such as guides and reamers, the success of these procedures depends to a greater extent upon the specialized skills of a particular surgeon, more so than if such specialized instrumentation were available. Thus, there has existed a need in the art for a surgical procedure with a range of associated specialized instrumentation to facilitate repair or replacement of the ACL.

Method and apparatus for arthroscopic knee surgery


Layer structures for making direct metal-to-metal bonds at low temperatures and shorter annealing durations in microelectronics are provided. Example bonding interface structures enable direct metal-to-metal bonding of interconnects at low annealing temperatures of 150° C. or below, and at a lower energy budget. The example structures provide a precise metal recess distance for conductive pads and vias being bonded that can be achieved in high volume manufacturing. The example structures provide a vertical stack of conductive layers under the bonding interface, with geometries and thermal expansion features designed to vertically expand the stack at lower temperatures over the precise recess distance to make the direct metal-to-metal bonds. Further enhancements, such as surface nanotexture and copper crystal plane selection, can further actuate the direct metal-to-metal bonding at lowered annealing temperatures and shorter annealing durations.

Making electrical connections at bonding interfaces has become paramount in microelectronics, as the transistor density that can be arrayed in a given 2-dimensional area has doubled every 18-24 months, for decades. Conventional flip chip connectors between semiconductor die and circuit board provide 45 contact bump connections per square millimeter (sq. mm), with each connection averaging 180 microns (μm) in bonding pitch. Conventional micropillar connectors improve upon conventional flip chip connectors, providing 625 pillar connections per sq. mm, with each connection averaging 40 μm in pitch. Bond pad width may be considered the size of the conductive pads to be bonded, while pitch refers to the distance between connections. Making 1,000,000 connections per sq. mm requires a bond pitch of 1 μm, for example, with a pad size that is likely around 0.5 μm. For wafer-to-wafer or die-to-wafer bonding that includes electrical interconnects, direct bonding techniques that include direct metal-to-metal bonding, such as "direct bond interconnect" (DBI® brand) direct hybrid bonding, can provide 100,000-1,000,000 connections per sq. mm, with each connection averaging from <1 μm-40 μm in pitch (Invensas Inc., a subsidiary of Xperi Corp., San Jose, Calif.). Even greater connection density is feasible with connections that are less than 1 μm in pitch.
Direct hybrid bonding processes, such as DBI® direct hybrid bonding, presuppose ultra-flat bonding surfaces, and so high density connections to be made by such direct bonding rely on varieties of chemical-mechanical planarization (CMP) processes to make the surfaces to be bonded flat to within a few ten-thousandths of a micron (within a few tenths of a nanometer) over a large surface. Various CMP processes can achieve a depth-of-field flatness sufficient for photolithography, or sufficient for 22 nanometer node technology, for example.
To achieve such exceptionally fine-pitch 3D electrical interconnects at ultra-high density, the alignment and bonding processes must also be finely tuned. The alignment and dielectric (nonmetal) bonding parts of the direct hybrid bonding process can be performed at room temperature. The dielectric portions of the bonding surfaces (for example, silicon oxide) forms oxide-to-oxide bonding spontaneously when the prepared surfaces are brought together. The metal pads or vias that are confined in the dielectric material, however, are slightly recessed from the dielectric surface that makes up the horizontal bonding interface, such that the metal pads do not impede bonding of the dielectric surfaces upon contact of the dielectric surfaces with each other.
Conventional annealing stages of direct hybrid bonding processes are at a raised temperature. At these higher annealing temperatures, the metal pads or vias expand vertically more than the surrounding dielectric material, due to the difference in coefficients of thermal expansion (CTEs) between metals and dielectrics. If the recess is sufficiently shallow, the metal vias or pads on each side of the surface being bonded will expand to bridge the small gap between the two metal surfaces and form a physical contact with each other at a certain self-expansion. The oxide-to-oxide bonding of the dielectrics around the metal pads further strengthens at these higher annealing temperatures to allow the metal pads to expand into each other and permanently bond. Bonding between metal pads initiates when copper atoms (for example, for copper pads) at each surface begin to make mutual metallic bonds with other copper atoms on the other side of the interface. No solder or other adhesives are used in the direct hybrid bonding process of electrical interconnects in this manner.
But the temperatures used in conventional annealing steps for direct hybrid bonding can place thermal stress on ever-smaller semiconductor components used in microelectronics. This annealing temperature could be lowered, but thermal expansion at lower temperatures is limited and requires very precise control of copper pad placement with respect to the recess distance of the metal pads from the bonding interface at room temperature, a precise control that is difficult to achieve in high volume manufacturing. This recess distance results from the CMP step, resulting in a very narrow manufacturing window that is impractical: any slight protrusion of the metal pad above the horizontal plane of the bonding interface composed of the dielectric surface can impede the spontaneous dielectric bonding phase of the direct hybrid bonding process that occurs at room temperature, and this causes overall bonding failure. Structures and processes that could otherwise lower the annealing temperature for direct metal-to-metal bonding of interconnects are desirable for further progress in 3D semiconductor packaging.

Layer structures for making direct metal-to-metal bonds at low temperatures in microelectronics


A sealing device with convertible magnetic sealing medium includes a housing with an accommodation cavity formed therein, a rotary shaft rotatably disposed in the accommodation cavity, a first pole piece disposed on the rotary shaft, a second pole piece fitted over the rotary shaft, and a permanent magnet fitted over the rotary shaft between the first pole piece and the second pole piece. The rotary shaft has a first blind hole, a second blind hole, a first via hole and a second via hole. A plurality of first pole teeth are provided in an inner circumferential wall of the first pole piece and a plurality of second pole teeth are provided in an inner circumferential wall of the second pole piece. Magnetic powder is provided between a top surface of each of the first and second pole tooth and the outer circumferential surface of the rotary shaft.

Magnetic powder is a powder composed of nanoparticles wrapped by surfactants, which exhibits superparamagnetism under a magnetic field. A sealing device with magnetic powder may withstand a large pressure difference and have a high pressure capability, but is not capable of acquiring zero leakage of the sealed object, with zero leakage herein meaning the leaking rate is lower than 10-11 cm3/s. Magnetic fluid is a stable colloid formed by uniformly dispersing nanoparticles wrapped by surfactants into a carrier liquid. A sealing device with magnetic fluid is capable of acquiring zero leakage of the sealing device, but may withstand a relatively small pressure difference. The sealing device in the related art, however, is not capable of switching states of the sealing medium depending on sealing requirements to meet requirements of high pressure resistance or zero leakage.

Sealing device with convertible magnetic sealing medium


System and method for selection of appropriate modeling data from a general data set to characterize a modeled process. The data is typically correlated sensor data, representing a multitude of snapshots of a sensed machine or process. The invention accommodates selection of greater amounts of general data for inclusion in the modeling data where that data exhibits greater dynamics, and selects less data from regions of little change. The system can comprise a computer running a software program, or a microprocessor.

1. Field of the Invention
The present invention relates generally to equipment and process monitoring, and more particularly to monitoring systems instrumented with sensors that measure correlated phenomena. The present invention further relates to modeling instrumented, real-time processes using the aggregate sensor information to ascertain information about the state of the process, and a method of training an empirical model used therein.
2. Description of the Related Art
Conventional methods are known for monitoring equipment or processes—generically "systems"—using sensors to measure operational parameters of the system. The data values from sensors can be observed directly to understand how the system is functioning. Alternatively, for unattended operation, it is known to compare sensor data values against stored or predetermined thresholds in an automated fashion, and generate an exception condition or alarm requiring human intervention only when a sensor datum value exceeds a corresponding threshold.
A number of problems exist with monitoring systems using thresholds. One problem is the difficulty of selecting a threshold for a dynamic parameter that avoids a burdensome number of false alarms, yet catches real alarms and provides sufficient warning to take corrective action when a system parameter—as measured by a sensor—moves outside of acceptable operation. Another problem is posed by sensor failure, which may result in spurious parameter values. It may not be clear from a sensor data value that the sensor has failed. Such a failure can entirely undermine monitoring of the subject system.
In systems with a plurality of sensors measuring correlated phenomena in the system, it is known to use certain methods to consider all sensors in aggregate to overcome some of these problems. By observing the behavior of all the sensor data values in aggregate, it can be possible to dramatically improve monitoring without suffering unduly from false and missed alarms. Also, knowledge of how all the correlated parameters behave in unison can help determine that a sensor has failed, when isolated monitoring of data from that sensor would not in and of itself indicate the sensor failure.
Known methods for viewing aggregate sensor data typically employ a modeling function that embodies prior knowledge of the system. One such technique known as a "first-principles" model requires a well-defined mathematical description of the dynamics of the system selecting system snapshots taken at minimum and maximum system parameter excursions. The mathematical model is used as a reference against which current aggregate sensor data can be compared to view nascent problems or sensor failures. However, this technique is particularly vulnerable to even the slightest structural change in the observed system and may not provide sufficient system characterization in operating regions where system parameters vary most dynamically. The mathematical model of the system is often very costly to obtain, and in many cases, may not be reasonably possible at all.
Another class of techniques involves empirically modeling the system as a "black box", without discerning any specific mechanics within the system. System modeling using such techniques can be easier and more resilient in the face of structural system changes. Modeling in these techniques typically involves providing some historic sensor data corresponding to desired or normal system operation, which is then used to "train" the model.
One particular technique is described in U.S. Pat. No. 5,987,399, the teachings of which are incorporated herein by reference. As taught therein, sensor data is gathered from a plurality of sensors measuring correlated parameters of a system in a desired operating state. This data is used to derive an empirical model comprising certain acceptable historical system states. Real-time sensor data from the system is provided to a modeling engine embodying the empirical model, which computes a measure of the similarity of the real-time state to all prior known acceptable states in the model. From that measure of similarity, an estimate is generated for expected sensor data values. The real-time sensor data and the estimated inspected sensor data are compared, and if there is a discrepancy, corrective action can be taken.
Other empirical model-based monitoring systems are disclosed in U.S. Pat. No. 4,937,763 to Mott, wherein learned observations are employed in a system state analyzer, and U.S. Pat. No. 5,764,509 to Gross et al., the teachings of which are hereby incorporated by reference. Selection of the appropriate historical sensor data for generating any of these empirical models is a serious hurdle. The models variously rely on the historic data accurately representing the "normal" conditions of the process or machine being monitored. Therefore, one must ensure that the data collected as historic data corresponds to an acceptable state of operation, and not one in which a latent fault was present in the process or machine. A larger problem is then to ensure that the historic data is sufficiently representative of the expected ranges of operation, so that the empirical model does not generate alarms for states of operation it has no history for, but which are otherwise acceptable states for the process or machine. It is critical to the success of the empirical model for monitoring that the collected sensor data be properly distilled or condensed to a trained set of data that adequately represents the knowledge of the normal states of operation of the process or machine being monitored. An additional problem is that, since empirical modeling methods can be computationally demanding, it is often preferable to restrict the historic data on which they are built or trained to a minimum, in order to reduce training time and required computing power. Finally, some empirical models are actually adversely affected by too much training data: They tend to find every current state of the monitored process or machine acceptable, because something close enough to it can be found in the historic data. Therefore, a successful selection of representative "training set" data must not result in an "overtrained" model.
In U.S. Pat. No. 5,764,609 to Gross et al., a training method for selecting observations of time-correlated sensor data called Mim-Max is presented. According to this way of training a model, the collected normal sensor data is condensed or distilled down to a "training set" by selecting those observations (or "snapshots") that contain a global maximum or minimum for a sensor with respect to all values taken on by that sensor across the entire collected sensor data. Thus, as a maximum the number of observations that are included in the training set that results from the training is twice the number of sensors being modeled. While this method assures the inclusion of extrema for all sensors in the model, it may be desirable to enhance the model with inclusion of other snapshots with intermediate values.
Therefore, when selecting vector-arranged snapshot data for inclusion in a training set for deriving an empirical model, there is a need for selecting an optimized training set that best characterizes the dynamics of the underlying machine or process. There is a further need for a method for selecting historic data that minimizes the size of the training set. Finally, there is a need for training methods that are computationally efficient and fast. This invention achieves these benefits by automating selection in a way that maximizes the data membership from regions of great dynamics, while keeping the overall training set size manageable.

System for extraction of representative data for training of adaptive process monitoring equipment


The apparatus includes a first plate for supporting the first surface of the article adjacent to the edge part of the article, a second plate extending from one end of the first plate in order to support the second surface of the article adjacent to the edge part of the article, a band connected to both side ends of the first plate such that a worker is able to securely hold the apparatus using one hand, and a non-skid member attached to at least one of inner surfaces of the first and second plates, which make contact with the first and second surfaces of the article, so as to prevent the apparatus from sliding along the article.

1. Field of the Invention
The present invention relates to a cutting tee square. More particularly, the present invention relates to a cutting tee square equipped with cutting tools for simply and rapidly performing cutting work or drawing work with respect to various plate members.
2. Description of the Prior Art
As generally known in the art, a tee square is one of drawing instruments used for drawing lines. The tee square includes a body formed with scale marks and a head installed perpendicularly to the body. The user can draw various lines using the body of the tee square or set squares cooperating with the body of the tee square while moving the tee square up and down along a lateral side of a drawing board in a state in which a basis plane of the head closely adheres to the lateral side of the drawing board. Meanwhile, a cutting tee square has been developed by modifying the tee square in order to cut various plate members used as construction materials, such as boards, panels or glass plates.
For instance, Korean Utility Model Registration No. 20-32981 discloses a "board cutting ruler" in which a fixing square is movably installed in a hole of a transverse bar, one end of a ruler formed with scale marks is coupled to the fixing square, and a slider is coupled to the ruler such that the slider can move lengthwise along the ruler. In addition, a cutter blade is installed on a lower surface of the slider so as to cut a board. According to the above board cutting ruler, the fixing square moves lengthwise along the transverse bar together with the ruler or the slider moves lengthwise along the ruler in such a manner that the board or plate members can be cut by means of the cutter blade.
In addition, Korean Utility Model Registration No. 20-32981 discloses a "glass cutting T-measure" in which one end of a square is fixed to the center of an upper surface of a support member and a cutter is installed on the square such that the cutter can move lengthwise along the square. According to the above glass cutting T-measure, the cutter moves lengthwise along the square in a state in which the support member closely adheres to one end of the glass plate, thereby cutting the glass plate.
However, according to the above conventional cutting squares, the user must move the cutter lengthwise along the square in order to cut the plate member. Therefore, when it is necessary to cut a plate member having a length larger than that of the square, the user must repeat the cutting work several times while moving the cutting square along the cutting line formed in the plate member. Since the cutting work for the plate member must be performed several times, workability may be significantly degraded.
In addition, the board cutter and the glass cutter are dedicated to cut the board and glass, respectively. Accordingly, the user must purchase both the board cutter and the glass cutter, which imposes excessive expenses on the user and causes inconvenience to the user because the user must carry the board cutter and the glass cutter so as to use them.
Meanwhile, an ink scale is used in various construction fields in order to draw lines on plate members. That is, after measuring the size of the plate member, drawing lines are marked on both side ends of the plate member. Then, one end of the ink scale is fixed to the drawing line marked on one end of the plate member and the other end of the ink scale is aligned corresponding to the drawing line marked on the other end of the plate member. In this state, the user pulls and releases the ink scale in such a manner that ink marks can be formed on the plate member. However, this may lengthen working time while complicating the drawing work.


Disclosed in a process for making (1) a compound of the formula NC—CH2—CH2—CH2—CH2—CO2R′, wherein R′ is H or C1 to C12 alkyl, or (2) adipic acid or (3) dimethyl adipate, using as the substrate, 3-pentenenitrile, (2) 3-pentenoic acid or methyl 3-pentenoate, respectively, by contacting the substrate with carbon monoxide and a nucleophile in the presence of a Group VIII metal, a selected ligand, and an acid promoter. The nucleophile, which (a) an alcohol or water, or (b) water or (c) methanol, respectively, in the presence of a Group VIII metal, preferably palladium, a selected phosphine ligand, and an acid promoter.

Two processes are known in the art for the preparation of caprolactam from butadiene. The first process involves the following steps: (1) stepwise addition of two equivalents of hydrogen cyanide to butadiene to produce adiponitrile, (2) partial hydrogenation of adiponitrile to form 6-aminocapronitrile, (3) separation of 6-aminocapronitrile from fully hydrogenated hexamethylenediamine and unreacted adiponitrile, and (4) hydrolysis of 6-aminocapronitrile and cyclization of the hydrolysis product to produce caprolactam.
The second process involves the following steps: (1) carbonylation of butadiene to methyl 3-pentenoate, (2) hydroformylation of methyl 3-pentenoate to methyl 5-formylvalerate, (3) reductive amination of methyl 5-formylvalerate to methyl 6-aminocaproate, and (4) cyclization of methyl 6-aminocaproate to caprolactam.
It would be desirable to develop a process that produces fewer by-products than the above processes and involves fewer reaction steps. A process that satisfies these needs could be based on the carbonylation of 3-pentenenitrile to 5-cyanovaleric acid or its corresponding esters. The process to produce caprolactam would involve the steps of: (1) hydrocyanation of butadiene to 3-pentenenitrile, (2) carbonylation of 3-pentenenitrile to 5-cyanovaleric acid or ester, and (3) hydrogenation and cyclization of 5-cyanovaleric acid or ester to caprolactam.
In order to develop a successful process, an active, selective catalyst that operates under mild conditions for the carbonylation of 3-pentenenitrile is needed. Previous attempts to produce methyl 5-cyanovalerate or 5-cyanovaleric acid from 3-pentenenitrile were based on the use of a cobalt catalyst. U.S. Pat. No. 5,434,290 discloses the use of a cobalt catalyst, an activating solvent comprising carbonic diesters, carbamates or ureas and CO pressures between 210 to 270 bar to convert 3-pentenenitrile to methyl 5-cyanovalerate. U.S. Pat. No. 4,508,660 discloses a similar process, but using sulfones as the preferred solvent and CO pressures between 14 to 35 MPa. The rates of carbonylation reported in this patent are quite low, the turnover frequency calculated for example 2 of U.S. Pat. No. 4,508,660 gives 1.52 mol/mol-hour. A similar situation is described in U.S. Pat. No. 4,933,483.
Palladium-based catalysts for the carbonylation of olefins and diolefins are known in the art. U.S. Pat. No. 5,028,734 discloses a process for the selective carbonylation of conjugated dienes in the presence of an alcohol and a catalyst system comprising a halide-free palladium salt, a bidentate phosphine ligand and a protonic acid with a pKa value greater than 3. PCT patent application WO 00/56695 discloses a process for the carbonylation of conjugated dienes by reaction with CO and alcohol in the presence of a catalyst system including a source of palladium cations, a phosphorus-containing ligand of structure X1—R—X2 and a source of anions. The preferred ligands are based on a 9-phosphabicyclononyl group for X1 and X2 and a simple bridge for R. PCT patent application WO97/38964 describes the use of the same catalyst system for the carbonylation of ethylenically unsaturated compounds.
PCT patent application WO 98/42717 describes a catalyst of the formula R1>P—R2—PR3R4 for the carbonylation of terminal and internal olefins. The R1>P moiety is a substituted 2-phospha-tricyclo[18.104.22.168{3,7}]decyl group where one or more of the carbon atoms are replaced by hateroatoms, in particular oxygen. Comparisons are made between phosphines such as (Me3C)P(CH2)3P(CMe3) (DTBPP) and 1,3-P,P′-di(2-phospha-1,3,5,7-tetramethyl-6,9,10-trioxatricyclo[3.3.11{3.7}]decyl propane (DPA3). Carbomethoxylation of an internal-C14 olefin feed with a palladium-based catalyst using DPA3 as a ligand gives linear methyl ester with 78% selectivity at an average rate of 120 mol/mol-hour. In contrast, using DTBPP as ligand under identical conditions gives only an average rate of 5 mol/mol-hour.
PCT patent application WO96/19434 and Chem Comm., 1999, 20, 1877-1878 describe the use of bidentate phosphines such as bis(di-t-butyl phosohino)-o-xylene for the carbonylatlon of ethylene to methyl propanoate. The patent application describes catalysts using these bidentate phosphines as being unable to carbonylate propene. One skilled in the art might reason that if such catalysts are able to carbonylate ethylene, but fail to carbonylate propene at any appreciable rate, then these same catalysts would be inactive for the carbonylation of internal olefins. Surprisingly, these catalysts are able to convert an internal olefin, namely 3-pentenenitrile, to the corresponding linear carboxylic acid, namely 5-cyanovaleric acid (or its alkyl esters). Additionally these catalysts are able to convert 3-pentenoic acid to adipic acid, and to convert methyl 3-pentenoate to dimethyl adipate.


A technique to perform fast decoding of a Reed-Solomon code. A first multiplier unit multiplies a matrix Bh with a column vector v using common adders to produce a column vector v1. The vector v represents one of an error locator polynomial, an error evaluator polynomial, and a derivative polynomial for a (n, k) Reed-Solomon code. The matrix Bh is over GF(2) including first h columns of a matrix B. A second multiplier unit multiplies non-unity components of a column vector A with non-zero components of the column vector v1 component-wise in GF(q) to produce a column vector v2, q being equal to n+1. A third multiplier unit multiplies diagonal sub-matrices of a matrix C with corresponding components of the column vector v2 in GF(2) to produce a column vector v3.

1. Field of the Invention
Embodiments of the invention relate to the field of error correction technology, and more specifically, to Reed-Solomon code.
2. Description of Related Art
The Reed-Solomon code is a block-based error correcting code with a wide range of applications in digital communications and storage. It is typically used to correct errors in many systems including: storage devices (e.g., tape, compact disk, digital vide disk, barcodes, etc), wireless or mobile communications (e.g., cellular telephones, microwave links, etc), satellite communications, digital television, and high-speed modems. A Reed-Solomon codeword is generated using a special polynomial. All valid code-words are exactly divisible by the generator polynomial. A Reed-Solomon decoder attempts to identify the position and magnitude of up to t errors (or 2t erasures) and to correct the errors or erasures. Finding the symbol error locations typically involves solving simultaneous equations with t unknowns. In general, this includes finding an error locator polynomial and finding the symbol error values. Techniques to do this include the Berlekamp-Massey procedure to find the error-locator polynomial, the Chien search to determine the error positions by finding the zeros of the error locator polynomial, and the Forney algorithm to compute the error values. These techniques typically require evaluation of a polynomial at certain points.
Existing techniques to evaluate polynomial at certain points have a number of disadvantages. A popular technique is the Horner scheme. For a polynomial of degree n−1 and t roots, the Horner scheme needs tn additions and tn multiplications. The amount of computations may be high for many high-speed applications.


This invention relates to an electrically controllable solar building pane composed of two panels spaced apart by a layer of an intermediate gas, the panel facing towards the outside of the building being constituted of a variable transmission system of the electrochromic type comprising two transparent substrates composed, notably, of glass sheets, joined together by an ion-conducting organic polymer and coated on the jointing face with transparent electrically conducting films and films of anodic and cathodic electrochromic materials.

1. Field of the Invention
This invention relates to an architectural electrochromic pane; more specifically, the invention relates to a building pane, of which the transmission, reflection and energy-absorption factors can be modified by an electrical control.
2. Discussion of the Background:
For several years now, the development of air-conditioning systems has created an increasing demand for panes having a low solar gain factor, or in other words glazing panes which contribute as little as possible to the rise in temperature inside the building. For this purpose, architects have turned towards panes comprising a reflective glass for solar protection produced by deposition of a mineral film onto a clear glass or glass tinted within the mass, the deposition being carried out, for example, by a pyrolysis technique or a cathodic sputtering technique under vacuum of a film of metallic oxides.
Unfortunately, the immediate effect of these solar protection films is a reduction in the light transmission which, in the case of the most efficient products, from the point of view of the solar gain factor, requires the almost permanent need for artificial lighting inside the building. It will certainly be understood that this decrease in light transmission is to a large degree unavoidable if it is compared with the physical definition of the solar factor of a pane. That is to say, the solar factor is the ratio of the total energy entering the room through the pane, to the incident solar energy, the total energy being the sum of the solar energy entering by direct transmission and of the energy given up by the pane to the internal environment as a consequence of its heating up by energy absorption. In practice, furthermore, the user makes his choice above all on the basis of the light transmission level, the solar factor being a fallout from this choice.
On the other hand, the sunshine conditions vary from one period of the year to the other and according to the time of day. At the approach to nightfall or in winter in cold or temperate climates, the first concern is a high transmission of light. In contrast, during periods of high sunshine, a sufficient illumination can be obtained even with a very low light transmission percentage; the important thing then is certainly the solar reduction factor, in order to reduce the cost of air conditioning. Finally, and independently of all the sunshine conditions, it may be useful to darken a glazing pane, for example during a video projection.
It was, notably, with the objective of providing an evolutionary solution that electrochromic panes have been developed, that is to say very generally, panes having electrically controlled optical properties. To date, various electrochromic systems have been proposed for applications such as display devices, rear view mirrors with an antidazzle position or again automobile roofs, but no building glazing pane has been fully developed, since this application has always appeared in the technical literature as a still remote objective, not likely to be realized in the short term.
According to an article that appeared in "Solar Energy Materials", volume 22, no. 1, March 1991, Susan Reilly, Deriush Arnateh and Stephen Selkowitz have developed, from calculated models, what they believe to be the optimum configurations for the purpose of reducing the air-conditioning (cooling) and illumination loads. Although this article refers to purely theoretical electrochromic systems, they concluded that in the case of a monolithic pane it is preferable to place the electrochromic system on the face which is towards the outside, whereas in the case of double glazing, the system should preferably be placed on the panel which is towards the outside, but facing towards the intermediate layer of air. Furthermore, these authors mention the advantage of incorporating, in addition, one or more "static" selective films, such as low-emissivity films or sheets of tinted glass.
This article does not, however, take into account the practical constraints of the production of a building pane nor of the fact that an electrochromic system should, if possible, be placed in specific conditions suitable for preventing its degradation.


A high-pressure turbine of a gas-turbine engine provided with a turbine disk (1) carrying rotor blades (2) and with stator blades (3), and with a lateral wheel cavity (5) being formed between the turbine disk (1) and the stator ring (4), wherein a seal (8) is provided in axial direction between stator blade platforms (6) and rotor blade platforms (7) and which is arranged radially outwardly adjacent a main gas duct (9).

This invention relates to a high-pressure turbine of a gas-turbine engine.
More particularly, this invention relates to a high-pressure turbine of a gas-turbine engine with a main gas duct internal seal. Specifically, a turbine disk which carries the rotor blades is provided. Furthermore, the high-pressure turbine comprises, as usual, stator blades attached to a stator ring. A lateral wheel cavity is formed between the turbine disk and the stator ring.
On high-pressure turbines, the lateral wheel cavity must always be sealed appropriately against the main gas duct to enable cooling air for the cooling of the rotor blades to be fed via the lateral wheel cavity. The known designs of sealing arrangements have different overlaps between the platforms of the rotor blades and those of the stator blades. Here, the size of the gaps is such that the pressure of the main gas duct is essentially imparted to the lateral wheel cavity. With simple seal designs, the pressure disadvantageously is incapable of feeding a leading-edge cooling film for the rotor blades. To overcome these disadvantages, solutions are provided in the state of the art in which the lateral wheel cavity is divided into individual chambers by means of different seals. In these solutions, the mass flow for blade cooling is usually provided from a radial inner chamber, while a radial outer chamber primarily serves to prevent hot gas from flowing in from the main gas duct.
Here, it is disadvantageous that, in particular, the outer chamber, which is located at one of the hottest zones of the high-pressure turbine outside the main gas duct, is flushed by only a very low mass flow. Furthermore, this mass flow is additionally heated on its passage through a seal. All these factors result in a high thermal load of the turbine disk (disk rim of the first stage of the high-pressure turbine). This, in turn, entails a severe limitation of the life of the turbine disk.

Main gas duct internal seal of a high-pressure turbine


A gauge carrier for absorbing longitudinal and radial shock forces on a shock sensitive gauge in a gauge housing where the gauge is insertable and retrievable with a unit assembly. The gauge or gauges are coupled to a longitudinal shock absorber comprised of belleville springs by a ball and socket arrangement to isolate longitudinal shock waves from the gauge while annular resilient members provide radial shock absorption for the gauge in the housing. The longitudinal shock absorber can be selectively pre-loaded.

Downhole pressure and temperature measuring gauges are utilized in well bore operations to measure temperature and pressure conditions in the well bore. As disclosed and discussed in U.S. Pat. No. 4,628,995, a gauge carrier can be attached to a packer and a perforating device is lowered through the tubing to a location below the packer to perforate the well bore below the set packer. Alternatively, the perforating device can be attached to a pipe below the packer and run in the well bore while attached to the packer. In the '995 patent, the gauge carrier accommodates three gauges located around the circumference of the gauge carrier and each gauge carrier is shock mounted against longitudinal vibration by belleville springs. This system has been highly successful in isolating the shock sensitive pressure gauges from the longitudinal shock forces produced in the well bore during running in the well bore and from detonation of perforating guns when in the well bore.
One of the reasons that pressure gauges are sensitive to shock forces is that typically a quartz transducer is utilized for high accuracy measurement and these transducers are particularly sensitive to shock impact forces. Obviously, the well operator who has gone to the trouble of performing well operations to perforate and to obtain contemporaneous pressure measurements expects the pressure gauge to function. If the gauge malfunctions because the shock forces of the perforator damage the pressure gauge, be it quartz or otherwise, the entire operation is of no value.
The gauge carrier in '995 patent cannot be utilized in deep, small diameter well bores because it's O.D. is too large and it is not intended to be proximate to the perforator means. The smallest O.D. of a pressure gauge is right at 11/4" and thus to reduce the diameter, the gauges (if more than one is used) are stacked in line (end-to-end) and disposed within the central bore of a tubular carrier. Also, in deep, small diameter well bores, the perforating system utilized in conducting a drill stem test has to be lowered on drill pipe and the o.d. of the perforator has a relatively small clearance with respect to the i.d. of the well bore. Perforators used in such tests can utilize as much as a 100 feet of a shot density of four to six shots per foot below a testing packer can thus generate terrifically high shock loads in both longitudinal and lateral directions. Because of the shock loads encountered, the tubular gauge carrier has been spaced a long distance from the perforator to reduce the shock impact effects.
In an effort to get the pressure gauge nearer to the perforator (and thus to obtain more representative pressure measurements) it has been proposed to use pressure gauges coupled end-to-end to one another where the upper pressure gauge is connected to a longitudinal rod member which slidably passes through a spring support plate located in an upper sub member. The spring plate is fixed in position in the sub member. Helical springs are located on the shaft above and below the spring plate. The spring members are compressed to provide a counter balancing spring force so that the attached rod member and pressure gauges can vibrate or move up and down relative to the tool gauge carrier to reduce or dampen the longitudinal shock effects. At spaced intervals along the length of the pressure gauges are radially extending rubber finger centralizers which are short rubber finger elements extending outwardly from the pressure gauge housing to contact the inner wall of the gauge housing. The fingers are four in number and are located at 90.degree. relative to one another and are intended to isolate the gauges from contacting the wall of the gauge carrier in response to lateral shock waves. In this system, the rubber fingers do not provide reliable shock isolation in the lateral direction and the gauges are directly coupled to the rod member so that longitudinal shock effects can cause lateral movement of the gauges in the gauge carrier.
In still another device intended for high shock absorption, the gauges are centralized in a tubular carrier gauge housing by annular rubber or elastomer devices disposed at spaced intervals along the length of the gauges. The annular rubber devices provide for lateral shock absorption universally around the periphery of the gauges. The ends of the gauge carriers are respectively engaged by helical coil springs which are compressed during assembly to exert a centralizing spring force on the gauges within the gauge housing. The springs under compression provide for dampening the shock movement in a longitudinal direction. While this device provides independent lateral and longitudinal isolation of the shock forces from the gauge housing with respect to a gauge carrier, the device is complex and difficult to assemble in the field.
Since the deflection travel of the springs are limited, the assembly has to be matched to the gauge length to obtain the desired force. However, since the assembly is made by inside a housing, it is not possible to check the spring compression. Also where there are sequential tests, it is necessary to completely break down and reassemble the device for each test. Furthermore, if the gauges vary in length, substantial inventory of spare parts is required.