A joined tubular body comprises a titanium alloy pipe of which crystal grain is hard to coarsen at the time of welding or hot-extruding, which consists by weight percentage of at least one element selected from 0.01.about.10% of S, 0.01.about.10% of Se and 0.01.about.10% of Te (the total sum does not exceed 10%), one or both of 0.01.about.10% REM and 0.01.about.10% of Ca (the total sum does not exceed 10%), and the above pipe is joined to a titanium alloy pipe consisting of the above elements and also at least one element selected from Al.ltoreq.10%, V.ltoreq.25%, Sn.ltoreq.15%, Co.ltoreq.10%, Cu.ltoreq.10%, Ta.ltoreq.15%, Mn.ltoreq.10%, Hf.ltoreq.10%, W.ltoreq.10%, Si.ltoreq.0.5%, Nb.ltoreq.20%, Zr.ltoreq.10%, Mo.ltoreq.15%, and 0.ltoreq.0.1% (the total sum does not exceed 30%).

1. Field of the Invention
This invention relates to a titanium alloy excellent in weldability or joinability as a material for various titanium alloy members such as a pipe or so used in industrial fields of aerospace, chemistry, oil well drilling and the like, and further relates to a method for producing the titanium alloy members such as the titanium alloy pipe and a joined tubular body made of the titanium alloy.
2. Description of the Prior Art
Generally, a titanium alloy is superior in strength per unit mass and excellent in corrosion resistance and the like, therefore it has been used widely in industrial fields of aeropsace, chemistry, oil well drilling and so on.
The titanium alloy or titanium alloy member is joined through various joining methods such as TIG welding (tungusten inert gas arc welding), MIG welding (metal inert gas arc welding), friction welding, electron beam welding, laser beam welding, diffusion welding, brazing and the like.
In any joining methods, however, the titanium alloy base metal adjacent to the joined zone changes its property and deteriorates in its mechanical properties owing to the thermal effect at the time of joining, and it is difficult to ensure joint strength equivalent to the strength of the base metal in most cases. Accordingly, there has been a problem in that development of a titanium alloy of which quality is not deteriorated so remarkably by the thermal effect at the time of the joining is earnestly cried for.
On the other hand, in order to further make the most use of the excellent characteristics of the titanium alloy in the aforementioned industrial fields, it is dispensable to manufacture titanium alloy pipes from the titanium alloy. However, as conventional techniques for manufacturing the titanium alloy pipes, a few methods have been merely put to practical use, such as a method of bending the titanium alloy formed in a thin sheet into an O-like shape through a U-like shape and joining a seam of the titanium alloy sheet bent in the O-like shape, and a method of forming the titanium alloy pipe directly by cutting a titanium alloy block through machining.
However, in a case of the welded pipe which is manufactured by joining the seam of the titanium alloy sheet subjected to the so-called U-O bending, there is a problem in that it is difficult to manufacture the pipe with a thick wall since there is a limit in forming of the titanium alloy sheet.
Further, there is another problem in a case of the titanium alloy pipe by machine cutting in that cost of the pipe increases because the yield rate of the titanium alloy material and the production efficiency are remarkably low, though there is large room for selecting shapes and sizes.
Furthermore, it is also indispensable to join the titanium alloy pipes with each other in order to use the titanium alloy pipes as structural members. In the case of joining the titanium alloy pipes with large diameters and thick walls through the TIG welding or so, it takes considerably much time for the welding. Besides, it becomes difficult to ensure the quality of the welded joint especially in the joining at the job site, accordingly there is another problem in that it is restricted to apply the titanium alloy pipes to large-sized structures required for the joining at the job site indispensably.

Titanium alloy, member made of the titanium alloy and method for producing the titanium alloy member


The invention relates to a method and arrangement for removing gas from a fibre/liquid suspension in a fibre treatment line in a pulp mill, which line includes at least one stage in which the fibre/liquid suspension is treated and/or stored in a large container (2) before being conveyed for further treatment. The fibre/liquid suspension is conveyed to the large container via a vessel (15) which with its lower part communicates with the large container and has a significantly smaller horizontal sectional area than the large container, but extends upwards above the level (4) of the fibre/liquid suspension in the large container, with gas being removed from the fibre/liquid suspension (19) in the area (18) of the upper part of the smaller vessel by means of the area being subjected to a subatmospheric pressure.

1. Field of the Invention
The invention relates to a method and arrangement for removing gas from a fibre/liquid suspension in a fibre treatment line in a pulp mill, which line includes at least one stage in which the fibre/liquid suspension is treated and/or stored in a large container before being conveyed for further treatment.
2. Description of the Prior Art
It is commonly known that gas bubbles in fibre/liquid suspensions, whether the bubbles occur as free bubbles in the liquid between the fibers or as bubbles bound to the fibers, can lead to problems in different phases of the fibre treatment process. The nature of the problems varies in different parts of the fibre treatment line in the pulp mill, such as interruptions in the flow of the suspension through valves, screens, and so forth, and fibre flocculation, foaming, dewatering problems, and so forth. Also, in a subsequent paper-making machine, the occurrence of gas bubbles in the suspension can cause problems.
The gas in question can, for example, be air, oxygen, and the like. In general it is a question of various gas mixtures
The problem has been addressed in different ways in the prior art. For example, it is known to remove the gas from pumps which transport the suspension between the various treatment stations of the fibre treatment line. However, the capacity of these pumps to remove gas is limited, and this is particularly so when the pump is intended to transport very large flows of fibre/liquid suspension. It is also known to remove gases from large containers in the fibre treatment line, in which containers the fibre/liquid suspension is stored for a long period in order to be stirred and homogenized, for example, or subjected to another treatment. However, the subatmospheric pressure which is needed in such a container in order to achieve the desired degassing requires that the walls of the container be strengthened to such an extent that the overall construction becomes very expensive, which is an obvious disadvantage.

Method and apparatus for removing gas from a fibre-liquid suspension

Kvaerner Pulping Technologies Aktiebolag


An intensity compensation method for a display control device includes steps of obtaining a plurality of backlight duties of a plurality of backlights according to an image data; calculating a plurality of compensation gains according to the plurality of backlight duties and a non-uniform backlight profile, wherein the non-uniform backlight profile indicates a plurality of respective actual intensity distributions of the plurality of backlights; and compensating a plurality of first image intensities corresponding to a plurality of pixels of the image data according to the plurality of compensation gains, to obtain a plurality of second image intensities.

1. Field of the Invention
The present invention relates to an intensity compensation method and a display control device and an image display device applying the same, and more particularly, to an intensity compensation method and a display control device and an image display device applying the same for simultaneously compensating the intensity loss due to local dimming and the non-uniformity of the mura panel according to a non-uniform backlight profile in order to display the normal intensity of an image.
2. Description of the Prior Art
In general, the local dimming technology turns on the corresponding display region of a liquid crystal display (LCD) by different backlight intensity, so as to save power consumption.
For example, if an image is brighter in the first display region but darker in the second display region, the local dimming may control the cold cathode fluorescent lamp (CCFL) or the light emitting diode (LED) to turn on with a brighter intensity for the first displayed region while with a darker intensity for the second displayed region. Therefore, compared with turning on all backlight sources with maximum intensity in the normal operation, the local dimming technology can save the power consumption.
In such a condition, since the local dimming technology lower the intensity for parts of the display region, the conventional local dimming technique may further compensate and increase the image intensity (i.e., the polarizing degree for LCD to conducting light) of the image data before displaying the image (i.e., increase the image intensity to compensate the loss induced by lowering the backlight intensity) to prevent the users from being affected by the intensity loss.
On the other hand, in the prior art, when calculating the light leakage from a backlight in a display region that leaks to the other display regions, it is generally assumed that all the backlight sources of the panel are uniform. However, the backlight non-uniformity of the mura panel may result in the intensity non-uniformity. Therefore, a mura compensation is required when applying the local dimming technology to the mura panel.
The conventional technology performs the mura compensation when all the backlight sources are fully turned on. However, the local dimming may not fully turn on the backlight sources. Therefore, the conventional mura compensation may not be effectively applied to the local dimming. Thus, there is a need for improvement of the prior art.

Intensity compensation method and display control device and image display device applying the same


A storage tray for compact discs (CD's) having a central opening consisting of a flat panel base with a plurality of raised cantilever members (fingers), the plurality of raised fingers being referred to as a rosette. The ends of the fingers form a circular opening and are unattached at the end. The fingers have on the underside thereof, a reinforcing rib. Some or all of the fingers may have the reinforcing rib. The fingers with the rib still have sufficient flexibility to move slightly inward and outward when positioning a CD over the rosette.

Storage containers for holding one or more disc shaped elements having electronically stored recordings thereon (hereinafter referred to as CD) are well known particularly in the entertainment field and in the information storage field. These storage containers for CD's are so designed to hold one or more such CD's. In fact, one container arrangement or jewel box has an insertable tray such that a single CD jewel box can be converted into a two CD jewel box by employing an insertable tray (U.S. Pat. No. 5,284,243) without essentially changing the dimensions of the jewel box.
The trays are employed in CD containers used to support and secure CD's and are generally made from pigmented thermoplastic molding resins having a varying degree of impact resistance. As such, the tray particularly the circular cantilever member arrangement (hereinafter referred to as a "rosette") around which the CD is seated is able to withstand loading forces or impact during assembly, CD loading operations, shipping and handling by the ultimate consumer or user of the CD.
However, there is a growing demand today for greater graphic display in CD containers. Artists are requiring a clear see through tray or CD holder so that a larger percentage of graphic area is visible to the consumer. By this it is meant that more graphics with respect to the artist and/or entertainment contained on the CD is viewable by the prospective buyer, the user or ultimate consumer. In order to achieve a clear see through disc holder tray, a transparent plastic material must be used. The most economical material available is crystal polystyrene. A functional CD holder tray can be molded, generally by injection molding, from crystal polystyrene using existing molds and designs without requiring substantial changes to the mold or to the jewel box design. However, crystal polystyrene, while inexpensive relative to other transparent plastics, is nevertheless brittle and, as such, the central cantilever members of the rosette have a tendency to fracture and/or break away during loading, shipping and/or handling operations due to the low impact resistance or brittleness of the crystal polystyrene. This can result in the CD becoming somewhat moveable in the jewel box and as it moves about, the CD can be damaged impairing the recording media stored thereon. The fractured cantilever members can also move around in the container and damage the surface of the CD by scratching the surface. This also impairs the stored recording media thereon.
U.S. Pat. No. 5,417,324 discloses one method of reinforcing the cantilever members of the rosette of a CD storage tray. The invention of the U.S. Pat. No. 5,417,324 employs a rib interconnecting at least two opposite cantilever members or fingers.
U.S. Pat. No. 5,494,156 discloses reinforced members and posts forming the rosette and thereby increasing the impact resistance of the rosette.
However, none of the references disclose reinforcing the fingers of a rosette by molding a rib on the underside of the fingers.

Storage tray for holding disc shaped elements


A robotic movement system includes at least one orb-based transmission assembly that includes an orb mount structure to or in which a magnet is mounted. At least one motor and a plurality of rollers are also mounted to the orb mount structure. The rollers contact an orb, which is rotated via rotation of the rollers for displacement and rotation of the robotic platform. The orb also includes a magnet having a magnetic attraction to the magnet mounted to the orb mount structure to hold the orb in contact with the rollers. In exemplary embodiments, the robotic movement system can function as a navigation and displacement mechanism for a displaceable robotic system or as a robotic joint for robots or for living beings.

Drive systems have remained primarily centered around the same simple concepts for many years, typically relying on some sort of rotary power output, such as a car engine or electric motor, wherein the rotary drive power, in turn, is converted into linear motion of the entire system. These existing drive systems can be easily separated amongst the following different and distinct types of motion.
A first type of drive system is a tank drive. This type of drive train maneuvers by changing the speed of either side of the system, allowing a robot to drive forward and backward and also to turn. By speeding up or slowing down rotation on one side relative to the other, the robot is able to turn; and a small difference in the displacement of opposite sides is magnified causing the difference in displacement (or speed) to rotate the entire robot. A downside of this approach is that, at high speeds, a minor difference in rotation can lead to large directional changes, and this often is impractical at high speeds.
A second type of drive system uses Ackerman steering/articulation. These drive trains work by mechanically altering the orientation of one set of wheels, usually forward wheels, so that the direction of motion is turned along that new orientation. Typically, in these systems, only either the rear wheels or the front wheels are powered, much like in a car. Although more controllable at high speeds, robots employing Ackerman steering/articulation are much less maneuverable, and tend to have delayed or choppy turning—depending on how the steering is implemented.
A third type of drive system uses omni-wheels (i.e., omni-directional wheels) and Mecanum drive. Robots that employ this system typically use tank drive associated with unique sets of wheels. These wheels are either omni or Mecanum wheels—the common characteristic being that they have rollers mounted in the wheel set either perpendicular to the direction of overall rotation (omni) or at a 45 degree angle to it (Mecanum). These wheels work by generating a vector quantity. When normally driving, the robot behaves as any other tank-drive robot, but when driving the wheels against each other, a vector is generated which causes atypical movement. For example, when running Mecanum wheels towards each other the North-South force cancels causing the robot to move directly east or west, as if sliding. Omni wheels function in a similar way, but with perpendicular rollers. A disadvantage to these approaches is that the vector force drastically reduces power; and, due to the rollers, robots employing these systems can slide easily when outside forces act on them or when they attempt to change direction.
A fourth type of system is swerve drive, which tends to be the most difficult drive train to implement. Swerve drive works by independently rotating the entire orientation of each wheel. Additionally, each wheel is independently powered, meaning that the entire motor assembly, gearing, wheel and mounting are all rotated carefully and precisely so that neither mechanical nor electrical components are damaged. The end effect is that the robot is able to move in any direction, but that there is a delay in change of direction; moreover, a large number of safety procedures typically are needed to prevent the robot from damaging itself. Physically, these requirements and characteristics typically make swerve robots heavy, slow, and difficult to build.


Methods of using azide-modified biomolecules, such as fatty acids, carbohydrates and lipids, to treat a plant, an insect or an animal infected with a virus or to inhibit infectivity of a virus, such as the human immunodeficiency virus, are provided. Also provided are methods of labeling a virus, such as human immunodeficiency virus, with an azide-modified biomolecule, such as a fatty acid, a carbohydrate, or an isoprenoid lipid. Also, provided are methods of tracking a virus in vivo, with an azide-modified biomolecule, such as a fatty acid, a carbohydrate, or an isoprenoid lipid. The azide-modified biomolecules may be combined with a pharmaceutically acceptable excipient to produce a pharmaceutical composition, optionally containing another anti-viral agent and/or a delivery agent, such as a liposome.

Viral infections account for significant morbidity and mortality in humans and animals. In addition, viral infections also result in significant agricultural losses, with plant viruses causing an estimated $60 billion in lost crop yields throughout the world each year. Although significant resources have been dedicated to identifying compounds having anti-viral properties, viral infections continue to present a significant risk to human health and agriculture.
In addition, the usefulness of most existing anti-viral treatments is limited by the development of multidrug resistance, poor efficacy, and/or toxicity. In fact, many anti-viral treatments are highly toxic and can cause serious side effects, including heart damage, kidney failure and osteoporosis. Other challenges include creating a drug that is broadly applicable in combating many different types of viral infections, which can be particularly important in the treatment of immunocompromised individuals.
One virus in particular, the human immunodeficiency virus (HIV), remains a global pandemic despite the development of antiretroviral drugs targeting HIV. As of 2007, it was estimated that more than 33 million people were infected with HIV, and HIV associated diseases represent a major world health problem. HIV is a retrovirus that infects CD4+ cells of the immune system, destroying or impairing their function. As the infection progresses, the immune system becomes weaker, leaving the infected person more susceptible to opportunistic infections and tumors, such as Kaposi's sarcoma, cervical cancer, lymphoma, and neurological disorders. The most advanced stage of HIV infection is acquired immunodeficiency syndrome (AIDS). It can take 10-15 years for an HIV-infected person to develop AIDS. Certain antiretroviral drugs can delay the process even further.
Although much effort has been put forth into designing effective therapeutics against HIV, currently no curative anti-retroviral drugs against HIV exist. Several stages of the HIV life cycle have been evaluated as targets for the development of therapeutic agents (Mitsuya, H. et al., 1991, FASEB J 5:2369-2381). One area of focus has been the HIV reverse transcriptase enzyme. Reverse transcriptase copies the HIV, single stranded RNA genome into double-stranded viral DNA. The viral DNA is then integrated into the host's chromosomal DNA where the host's cellular processes, like transcription and translation, are used to produce viral proteins and ultimately new virus particles. Therefore, interfering with reverse transcriptase inhibits HIV's ability to replicate. One class of reverse transcriptase inhibitors is nucleoside analogs, such as Zidovudine (AZT), Didanosine (ddI), Zalcitabine (ddC), and Stavudine (d4T), Lamivudine (3TC), Abacavir (ABC), Emtricitabine (FTC), Entecavir (INN), and Apricitabine (ATC) (Mitsuya, H. et al., 1991, Science 249:1533-1544; El Kouni, Curr Pharm Des, 2002, 8:581-93; Sharma et al., Cur Top Med Chem, 2004, 4:895-919). Another class of reverse transcriptase inhibitors is nucleotide analogs, such as Tenofovir (tenofovir disoproxil fumarate) and Adefovir (bis-POM PMPA) (Palmer et al., AIDS Res Hum Retroviruses, 2001, 17:1167-73). These nucleoside and nucleotide compounds are analogs of the naturally occurring deoxyribose nucleotides, however, the analogs lack the 3′-hydroxyl group on the deoxyribose sugar. As a result, when the analogs are incorporated into a growing viral DNA chain, the incoming deoxynucleotide cannot form a phosphodiester bond with the analog that is needed to extend the DNA chain. Thus, the analogs terminate viral DNA replication. Another class of reverse transcriptase inhibitors is the non-nucleoside reverse transcriptase inhibitors, such as Efavirenz, Nevirapine, Delavirdine, and Etravirine (El Safadi et al., Appl Microbiol Biotechnol, 2007, 75:723-37). They have a different mode of action than the nucleoside and nucleotide inhibitors, binding to the reverse transcriptase and interfering with its function.
The late stages of HIV replication involve processing of certain viral proteins prior to the final assembly of new virions. This late-stage processing is dependent, in part, on the activity of a viral protease. Thus, another area of focus in the development of antiretroviral drugs is protease inhibitors, such as saquinavir, ritonavir, indinavir, nelfinavir, amprenavir, lopinavir, and atazanavir (Erickson, J., 1990, Science 249:527-533; Klei et al., J Virol, 81:9525-35).
Other antiretroviral drugs target viral entry into the cell, the earliest stage of HIV infection. For HIV to enter a cell, its surface gp120 protein binds to CD4, exposing a conserved region of gp120 that binds to a CCR5 or a CXCR4 co-receptor. After gp120 binds to the co-receptor, a hydrophobic fusion peptide at the N-terminus of the gp41 envelope protein is exposed and inserted into the membrane of the cell. Entry inhibitors work by interfering with any stage of the viral entry process. For example, recombinant soluble CD4, for example, has been shown to inhibit infection of CD-4+ T-cells by some HIV-1 strains (Smith, D. H. et al., 1987, Science 238:1704-1707). Similarly, TNX-355 is a monoclonal antibody that binds CD4 and inhibits binding to gp120 (Kuritzkes et al., J Infect Dis, 2004, 189:286-91). BMS-806 binds to the viral envelope protein and inhibits binding to CD4 (Veazy et al., Nature 2003, 438:99-102). Co-receptor binding can be inhibited by several CCR5 inhibitors, including SCH-C and SCH-D, UK-427,857, maraviroc, vicriviroc, and an anti-CCR5 antibody (PRO-140) (Emmelkamp et al., Eur J Med Res, 2007, 12:409-17). Co-receptor binding can also be inhibited by the CXCR4 inhibitors AMD3100 and AMD070 (De Clerq, Nature Reviews Drug Discovery 2003, 2:581-87). Other compounds, such as enfuvirtide, bind to gp41 and interfere with its ability to mediate membrane fusion and entry (La Bonte et al., Nature Reviews Drug Discovery 2003, 2:345-36).
While beneficial, these antiretroviral drugs often exhibit toxic side effects such as bone marrow suppression, vomiting, and liver function abnormalities. In addition, they are not curative, probably due to the rapid appearance of drug resistant HIV mutants (Lander, B. et al., 1989, Science 243:1731-1734). Drug-resistant HIV strains develop due to the very high genetic variability of HIV. This genetic variability results from several factors, including HIV's fast replication cycle, with the generation of 109 to 1010 virions per day, a high mutation rate of approximately 3×10−5 per nucleotide base per cycle of replication, and recombinogenic properties of reverse transcriptase.
To combat the development of drug resistant HIV strains, multiple drugs have been combined as part of highly active antiretroviral therapy (HAART) (El Safadi et al., Appl Microbiol Biotechnol, 2007, 75:723-37; Sharma et al., Cur Top Med Chem, 2004, 4:895-919). Currently HAART typically involves combining at least three drugs belonging to at least two classes of antiretroviral agents. As discussed above, these classes include nucleoside or nucleotide analog reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors, and entry inhibitors.
Thus, although a great deal of effort is being directed to the design and testing of anti-viral drugs, the search for new and improved methods of treating viral infections, such as HIV, continues.


Systems and method for facilitating trading in a financial exchange including generating a pitcard interface on a wireless handheld computer. The pitcard interface includes a plurality of information display windows; a plurality of user input controls; and a view-specific data window, wherein the selection, order and arrangement of data in the view-specific data window is dependent upon the view currently selected by the user. In particular examples the wireless handheld computer allows a user to customize the particular interface components with shortcuts, hints, and/or auto-fill capabilities that enable the user to enter transaction information quickly and efficiently. Because these customizations are selected for a specific user, they support the needs of the specific user and are more efficient than direct entry of all transaction information using keyboard/keypad entry devices.

1. Field of the Invention
The present invention relates, in general, to electronic data entry systems, and, more particularly, to a user interface, systems and methods for recording and entering data related to transactions on an trading floor.
2. Relevant Background
Securities, commodities and negotiable instruments are traded on various exchanges that strive to provide an efficient marketplace for the trading of products listed on the exchange. An "open outcry" auction market, such as a commodities exchange, provides floor trading facilities for the buying and selling of listed commodities.
Floor trading is generally confined to specified trading areas that are typically referred to as trading "pits" or "rings". Within a trading ring, floor traders vary in the scope of their trading activities. Some floor traders trade only for their own proprietary accounts or for the proprietary accounts of their employer; other floor traders only execute orders on behalf of others; and some floor traders trade for proprietary accounts and also execute orders for others. For convenience, this document shall use the term "broker" to refer to floor traders engaging in any or all of the trading activities noted above.
Floor brokers congregate in the trading rings or pits on the exchange floor where they announce a "bid" price for an offer to buy and an "ask" price for an offer to sell. A trade in any particular commodity generally will occur at or within the spread for best bid and best ask prevailing in the trading ring at that time. The best ask price is the lowest price that a seller is willing to accept and a best bid price is the highest price that a buyer is willing to pay. Exchange employees confirm transaction prices for executed transactions and also confirm on an ongoing basis throughout the trading session the prevailing best bid and ask prices that are provided by the various brokers. Exchange employees strive to ensure that executed trades are posted with the Exchange and also undertake other activities that facilitate trades and that maintain a fair and orderly market.
In a commodity exchange, using the example of the execution of an order for an off-floor customer, such a transaction is initiated by a customer who places or has previously placed an order to buy or sell a particular commodity. The order is then conveyed to the customer's broker or another trader representing the customer's broker on the trading floor. In the case of a broker trading on the broker's own account, the transaction is initiated by the broker directly. Typically, brokers tend to trade and to specialize in the commodity or commodities that are traded within the same trading ring. Brokers are known to other brokers on the trading floor by an identifying number or short name. The brokers announce offers on the trading floor to implement their customer's orders. For each commodity that is listed for trading at a commodity exchange, the exchange will indicate the number of contract months, which are sometimes referred to as delivery months that are listed for that commodity, and different delivery months may trade separately at separate prices.
At an exchange using a "pitcard" system for entry of executed trades to the exchange, once a buying broker and selling broker agree on a price, the selling broker and/or buying broker record the transaction on a pad of paper or a multipart form that includes forms that are called "pitcard" and that may include other forms that are sometimes referred to as "trading cards". The information that is recorded includes the commodity code, quantity, delivery month, price, as well as the ID number or name for the buyer's broker and seller's broker. At commodity exchanges using the pitcard system, the pitcard is physically thrown into the center of the trading ring by the buyer and/or seller, where it is collected by an exchange employee, clocked, and delivered to data entry personnel.
The extensive manual operations involved in the conventional trade recording system can lead to trade execution delays, illegibly transcribed orders, dropped slips, delayed delivery, and mismatches between buy-orders and sell orders that are not detected for some time. Although some exchange functions have been computerized, the basic activities of trade entry by brokers have posed problems for computerization. A root problem is that any transaction recordation system must support a peak level of trading volume of the exchange. In a stock exchange there is typically a specialist system in which each trader/broker handles a stock for a single company. Transactions are conducted between a relatively small number of individuals and so identifying and recording broker names/identifications is relatively easy. Moreover, in a stock exchange there is little variation in the type of information that must be captured for each transaction. Hence, even at very large transaction volumes the pace at which information is recorded and entered into the trading system is manageable.
In contrast, a commodity exchange such as the New York Mercantile Exchange ("NYMEX") may be organized as an open system in which many traders (e.g., 100-200 individuals) are gathered at the trading pit for a given commodity. A particular broker may only be actively trading with a subset of 10-20 individuals. Because of the large number of traders, just entering and recording the broker identification for a particular transaction is difficult as compared to many trading floor environments. Further, each given commodity involves contracts in a variety of delivery months, and may involve derivative products such as options. As a result of these factors, the amount of information and pace at which that information must be recorded and entered by brokers/traders is significantly greater than in trading floor environments such as a stock exchange.
To date, the paper-based workflow described above remains the only effective way to record and enter transaction information in many commodity exchanges. The paper-based workflow relies on transaction information written quickly by traders using various shorthand techniques with symbols and markings that may be intelligible only to particular brokers or exchange employees familiar with the brokers involved in a transaction. In this environment, trying to capture pen strokes in an electronic device is problematic as accurately translating the hurriedly written pen strokes is so complex that only humans have been able to perform the task. On the other hand, having brokers type in information using keyboard/keypad interfaces is time consuming and does not support the rate at which information needs to be captured.
U.S. Pat. No. 6,625,583 issued to Silverman et al. describes a handheld trading system interface that enables entry of trade information on a trading floor of a financial exchange. The system described by Silverman presents a complex, multi-function interface that is specifically adapted for a stock exchange. Many features of the Silverman order entry interface are intended to emulate or simulate a paper trade recordation system. As a result, the Silverman system is not able to handle order entry at a pace necessary for high transaction volume environments such as a commodity exchange.
Accordingly, a need exists for wireless hand-held computers that can be used to exchange information with floor brokers. Further, there is a need for a trade entry interface that exhibits ease of use and allows brokers to enter trade information at least as fast if not faster than paper-based systems. Consequently, improved hand-held computer systems for trade entry are desired.

Electronic pitcard for wireless financial exchange


Two resonant cantilever beams oscillate in a sinusoidal pattern. Mirrors disposed on the oscillating ends of the cantilever beams are used to multiplex two scanning and collecting light beams. The cantilever beam parameters and mirror configuration are selected so that the scanning light beam is on the first mirror during the linear portion of its scan. As the first cantilever beam oscillates out of the linear portion of the sine wave, the deflection of the first mirror is just great enough to allow the scanning beam to strike the second mirror during the linear portion of the second mirror's scan. The process is repeated twice each cycle. The collection lens is large enough to receive the full aperture of both mirrors at all times. Multiplexing of scanning diodes is also accomplished by a controller circuit which alternately enables diodes disposed on the ends of respective first and second cantilever beams during the linear portion of each sine wave oscillation.

1. Field of the Invention
The field of the invention relates to bar code reading at point of sale (POS) locations. In particular the field of the present invention relates to a low-cost laser scanning technique using resonant cantilever beam deflectors for multiplexing scanning and collecting light beams. The invention makes possible a laser scanner which is small, compact, and efficient.
2. The Prior Art
In conventional applications the scanner is mounted in the counter of the POS station. The clerk moves the labeled goods over the window of the scanner and a laser beam within the scanner continuously scans a volume in space above the window. The checker or salesperson moves the package through this space with the label facing the window. When a laser beam crosses the black and White bars, the intensity variations in the scattered light are detected by a photodetector within the scanner. These are then converted to electrical signals which are decoded into the information on the label.
3. BACKGROUND OF THE INVENTION
Normally the scanning is accomplished using a motor which drives a rotor on which are mounted a number of mirrors. Such scanners are described in U.S. Pat. Nos. 4,064,390, 4,699,447, 4,799,164 and many others.
A further method of scanning uses a rotating hologram as in U.S. Pat. Nos. 4,795,224 and 4,647,143. This family of scanners also uses motors and requires considerable space for the hologram and the motor.
Alternatively, bar code labels are scanned using a handheld scanner in POS stations. This type of scanner may use a small mirrored polygon like the in-counter scanners, or it may use other techniques to scan the laser beam. One method uses a galvanometer driven mirror to scan the beam in a single line.
Another conventional technique uses a stepper motor to rotate the mirror back and forth. The advantage of this is that there is less dead time compared to a polygon scanner and to a sinusoidal galvanometer scanner. In addition, less space is required. Such a scanner is described in U.S. Pat. No. 4,825,057. Another disadvantage of the reversing stepper motor design is that a significant time delay is required to stop and start the mirror. In addition, this design generally uses more power than other motor designs.
Resonant mechanical scanners have been introduced in an attempt to overcome the disadvantages inherent in motor driven scanners. Resonant mechanical scanners are employed in a wide variety of applications. They are used because of their high reliability, long life and low-power consumption. Sinusoidally oscillated mechanical scanners have minimum energization requirements and are mechanically and electronically simple in design, fabrication and operation.
Resonant mirror systems for scanning laser beams in bar code reading are well known in the industry. An improved low profile scanner is described in U.S. Pat. No. 4,732,440. The main disadvantage of conventional resonant scanners is that the beam scan is sinusoidal, resulting in a velocity variation which goes from zero to some maximum. This variation is a serious problem for scanning labels because the scan pattern is unusable during the period of low velocity. U.S. Pat. No. 4,859,846 describes a dual-mode resonant scanning system designed to reduce the velocity variation by making the oscillation triangular through the addition of a third harmonic resonance. However, this method also is not well adapted to scanning the parallel, perpendicular bars of the standard bar code label.

Laser beam scanner with low cost ditherer mechanism


A method of manufacturing green pepper powder is disclosed. The present disclosure relates to a method of manufacturing green pepper powder, which cleans green-colored peppers, removes the pepper stems and seeds, lyophilizes the green-colored peppers without stems and seeds under predetermined conditions, and pulverizes the lyophilized product to manufacture green pepper powder.

The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art.
In general, pepper powder (cayenne) refers to red pepper powder that is made in the same traditional way through drying and then grounding red peppers into powder. Ever since ancient times, chili peppers in powder and paste forms have been one of the foods that accounted for a big part of world cuisines, and people have the stereotype that pepper powder is normally reddish.
Sweet pepper (pimento, paprika, etc.) powder which is sold in the US market is equally red color, which is not much different from chili pepper powder in the Korean domestic market. Peppers often used in foods are processed red peppers, which are used not only in traditional foods such as kimchi, pepper paste, and various processed foods but also in various ways during or after cooking. In contrast, green peppers, sweet peppers, etc. are dedicated to the raw use, and they have limited uses. Improved standard of living prompted the food industry to emphasize differentiation even in the same kind of food, develop various flavors, and match people's tastes following consumer preferences. The food industry, however, has been stubborn about the 'red' color convention as far as the pepper powder is concerned, failing to fully satisfy consumers' tastes.
Green peppers ripen into red peppers, during which they are subject to a threat of disease and insect damage, and are prevented therefrom mainly through pesticide spraying. However, the red peppers harvested through such pest control works are highly likely to retain pesticide even after cleaning, which can threaten the public diet.
As a result, the conventional method of producing red pepper powder, e.g., the conventional method of sun-drying green-colored peppers results in nongreen peppers with their components changed, to prohibit the manufacturing of distinctive green pepper powder.

Method for preparing green chilli powder


A method of CSI-RS Measurement Timing Configuration (CMTC) is proposed. The CMTC timing window is specifically configured to UE for CSI-RS RRM/mobility measurement via Radio Resource Control (RRC) signaling. CMTC can be carrier-specific or measurement object (MO) specific configured. Multiple CMTC can be configured to a UE, in a carrier-specific or a measurement object (MO) specific fashion. For inter frequency measurement, one CMTC on a carrier can be configured. For intra frequency measurement, up to two CMTC on a carrier can be configured. The CSI-RS resources associated to a given cell shall be configured within one slot. The CSI-RS resources on a carrier can be configured in the carrier specific CMTC. A gap shall be configured to include the CMTC for inter-frequency measurement.

The wireless communications network has grown exponentially over the years. A Long-Term Evolution (LTE) system offers high peak data rates, low latency, improved system capacity, and low operating cost resulting from simplified network architecture. LTE systems, also known as the 4G system, also provide seamless integration to older wireless network, such as GSM, CDMA and Universal Mobile Telecommunication System (UMTS). In LTE systems, an evolved universal terrestrial radio access network (E-UTRAN) includes a plurality of evolved Node-Bs (eNodeBs or eNBs) communicating with a plurality of mobile stations, referred to as user equipments (UEs). The 3rd generation partner project (3GPP) network normally includes a hybrid of 2G/3G/4G systems. The Next Generation Mobile Network (NGMN) board, has decided to focus the future NGMN activities on defining the end-to-end requirements for 5G new radio (NR) systems.
Reference Signal Received Power (RSRP) and Reference Signal Received Quality (RSRQ) are key measurements of signal level and quality for LTE and NR networks. In cellular networks, when UE moves from cell to cell and performs cell selection, reselection and handover, UE needs to measure the signal strength and quality of the neighbor cells. Received Strength Signal Indicator (RSSI) measurements can be used to determine RSRP and RSRQ. RSSI measures the average total received power observed in OFDM symbols containing reference symbols in the measurement bandwidth over certain resource blocks. RSSI is measured over the entire bandwidth including noise, serving cell power and interference power.
In addition to RSSI/RSRP/RSRQ measurements, UE can be configured to measure synchronization signal (SS) blocks (SSB) and/or channel state information (CSI) reference signal (CSI-RS). In LTE, DMTC (DRS measurement timing configuration) was provided for DRS (Discovery reference signal), which includes PSS/SSS/CRS/CSI-RS. LTE CSI-RS used as DRS was piggy-backed to CRS resources, and no delicate measurement window for CSI-RS resources. In NR, SMTC (SSB measurement timing configuration) is provided for SSB RRM (Radio Resource Management), which avoids UE to keep searching SSB for a long time, especially for inter-frequency measurement.
However, currently NR lacks the concept of measurement window for NR CSI-RS RRM, and the CSI-RS resources for mobility are configured at per resources basis. This potentially complicates UE's implementation and increases UE power consumption. For example, CSI-RS resources could be configured spreading out in time domain, and UE would be mandated to keep monitoring. It is thus an objective of the current invention to reduce UE power consumption for CSI-RS RRM by confining CSI-RS for RRM measurement within the CSI-RS measurement timing configuration (CMTC) timing window.

Measurement timing configuration for CSI-RS


A multicast service transmission method and a device, the method comprising determining, by a core network device, a coverage requirement of a to-be-transmitted multicast service, transmitting, by the core network device, the coverage requirement to an access network device, where the coverage requirement is used to determine a transmission parameter used to transmit the multicast service to a terminal device, receiving, by the access network device, the coverage requirement, determining, by the access network device according to the coverage requirement, the transmission parameter, and transmitting, by the access network device, the multicast service to the terminal device according to the transmission parameter.

Currently, the 3rd generation partnership project (3GPP) standard is based on a cellular network, and a new air interface is designed to carry an internet of things (IoT) service by using a characteristic of a narrowband technology. Such IoT is referred to as the narrowband internet of things (NB-IoT). Compared with a conventional cellular network, an NB-IoT network is characterized by a smaller data packet generated by a service, a longer data transmission period, and lower costs of a terminal device connected to an NB-IoT base station. There may be a large quantity of terminal devices connected to one NB-IoT base station, to implement mass deployment of the terminal devices.
In the NB-IoT, a multicast transmission solution needs to be designed based on a single cell point to multipoint (SC-PTM) technology in long term evolution (LTE), to reduce resource overheads when a network performs a service having a multicast feature, for example, software upgrade. Based on characteristics of the service and the terminal device of the NB-IoT network, compared with the LTE, it is more difficult to ensure reliability and efficiency of an internet protocol (IP) data packet in multicast transmission of a radio access network in the NB-IoT. In an aspect, a multicast service is targeted at a plurality of terminal devices, and a base station does not learn of service subscription information of the terminal devices. Therefore, if a transmission parameter is directly determined by the base station, a coverage level used by the base station may not match actual needs of the terminal devices. For example, if a coverage level selected by the base station is excessively low, when there is a poorly covered terminal device in a cell, a multicast transmission success rate of the poorly covered terminal device is relatively low, and consequently the base station needs to retransmit service data to the terminal device. In addition, the poorly covered terminal device also consumes a relatively large quantity of unicast resources, and consequently overall resource consumption is relatively large. Because a large quantity of resources are consumed to transmit a multicast service with a high coverage level, if a coverage level selected by the base station is relatively high, when a terminal device that actually subscribes to the multicast service is relatively well covered, a large quantity of resources are wasted. In another aspect, the NB-IoT uses a relatively low modulation and coding scheme (MCS), and uses a very small transport block size (TBS) at a physical layer, to reduce terminal device costs. Therefore, for a same transport-layer or network-layer data packet on which multicast needs to be performed, for example, an IP data packet, the NB-IoT needs to use more transport blocks (TB) on a physical downlink shared channel (PDSCH) for carrying. If one or more TBs are incorrectly transmitted, the entire IP data packet is to be retransmitted. Consequently, a TB that is correctly received in the IP data packet also needs to be retransmitted, and network resources are wasted.

Multicast service transmission method and device


An algorithm for the promotion of terminal nodes to switch nodes in a PLC network reduces overall network overhead and collisions, while ensuring the appropriate selection of a switch node and minimizing the number of levels in a PLC network. It also ensures that the terminal nodes with appropriate signal-to-noise ratios (SNRs) are promoted. It is desirable to have a network with fewer levels. The disclosed approach favors the nodes that are closer to the DC to promote them as switch nodes. This is achieved by waiting for a smaller number of PNPDUs for a node that is closer to the DC in comparison to a node that is farther away from the DC.

Power line communication or power line carrier (PLC) is a system for carrying data on a conductor also used for electric power transmission. A wide range of power line communication technologies are needed for different applications, ranging from home automation to Internet access.
Electrical power is transmitted over long distances using high voltage transmission lines, distributed over medium voltages, and used inside buildings at lower voltages. Hence, electrical power grids allow for relatively low cost communication over long distances. Full- and half-duplex systems (both one-way and two-way systems) have been successfully used for decades for purposes such as automatic remote meter readings.
Power line communications systems operate by impressing a modulated carrier signal on a wiring system. Different types of power line communications use different frequency bands, depending on the signal transmission characteristics of the power wiring used. Since the power distribution system was originally intended for transmission of AC power at typical frequencies of 50 Hz or 60 Hz, power wire circuits have only a limited ability to carry higher frequencies. The propagation problem is a limiting factor for each type of power line communications. Data rates and distance limits vary widely over many power line communication standards. Low frequency (about 100-200 kHz) carriers impressed on high-voltage transmission lines may carry one or two analog voice circuits, or telemetry and control circuits with an equivalent data rate of a few hundred bits per second; however, these circuits may be many miles long. Higher data rates generally imply shorter ranges; a local area network operating at millions of bits per second may only cover one floor of an office building, but eliminates the need for installation of dedicated network cabling.
Narrowband power line communications began soon after electrical power supply became widespread. Around the year 1922 the first carrier frequency systems began to operate over high-tension lines with frequencies of 15 to 500 kHz for telemetry purposes, and this continues. Consumer products such as baby alarms have been available at least since 1940. In the 1930's, ripple carrier signaling was introduced on the medium (10-20 kV) and low voltage (240/415 V) distribution systems. For many years, the search continued for a low cost bi-directional technology suitable for applications such as remote meter reading. The EDF (French power utility) prototyped and standardized a system called "spread frequency shift keying" or S-FSK. (See IEC 61334.) This system is now a simple, low-cost system with a long history. However, it has a very slow transmission rate, between 200 and 800 bits per second. In the 1970's, the Tokyo Electric Power Co. ran experiments that reported successful bi-directional operation with several hundred units. Since the mid-1980's, there has been a surge of interest in using the potential of digital communications techniques and digital signal processing. The drive is to produce a reliable system that is cheap enough to be widely installed and able to compete cost effectively with wireless solutions.
Applications of mains communications vary enormously, as would be expected of such a widely available medium. One natural application of narrow band power line communication is the control and telemetry of electrical equipment such as meters, switches, heaters and domestic appliances. A number of active developments are considering such applications from a systems point of view, such as demand side management wherein domestic appliances would intelligently co-ordinate their use of resources, for example limiting peak loads. Control and telemetry applications include both 'utility side' applications, which involve equipment belonging to the utility company up to the domestic meter, and 'consumer-side' applications that involve equipment in the consumer's premises. Possible utility-side applications include automatic meter reading (AMR), dynamic tariff control, load management, load profile recording, credit control, pre-payment, remote connection, fraud detection and network management, and could be extended to include gas and water. A project of EDF, France includes demand management, street lighting control, remote metering and billing, customer specific tariff optimization, contract management, expense estimation and gas applications safety. Many specialized niche applications also exist that use the mains supply within the home as a convenient data link for telemetry. For example, in the UK and Europe a TV audience monitoring system uses power line communications as a convenient data path between devices that monitor TV viewing activity in different rooms in a home and a data concentrator that is connected to a telephone modem.
Several competing organizations have developed specifications, including the HomePlug Powerline Alliance, Universal Power line Association and HD-PLC Alliance. On December 2008, the ITU-T adopted recommendation G.hn/G.9960 as a standard for high-speed power line, coax and phone line communications. The National Energy Marketers Association was also involved in advocating for standards. IEEE P1901 is an IEEE working group developing the global standard for high-speed power line communications. In July 2009, the working group approved its "IEEE 1901 Draft Standard for Broadband over Power Line Networks: Medium Access Control and Physical Layer Specifications" as an IEEE draft standard for broadband over power lines defining medium access control and physical layer specifications. The IEEE 1901 Draft Standard was published by the IEEE in January 2010, and the final standard was approved on 30 Sep. 2010 and published on Feb. 1, 2011. NIST has included IEEE 1901, HomePlug AV and ITU-T G.hn as "Additional Standards Identified by NIST Subject to Further Review" for the smart grid in the United States. PRIME is one of the narrowband PLC technologies that has been widely adopted in Spain by utilities such as Iberdrola and Union Fenosa. Specifically, PRIME PLC system operation is defined in the draft Specification for Power Line Intelligent Metering Evolution incorporated by reference herein.
Increased use of PLC systems has generated the need for regularly obtaining data from all metered points in order to better control and operate the system. Specifically, there is a need for efficient selection of a switch node at the data concentrators, while also ensuring that the best possible node is chosen to be promoted as a switch node.

Advanced switch node selection for power line communications network


A method of operating a surgical control system comprises displaying an image of a surgical environment, from a field of view of an imaging instrument, on a display system. The display system is configured for mounting to a head of a user. The method also includes detecting an imaging control input from the user and responsive to the detection of the imaging control input, enabling an imaging control mode of the surgical control system. The method also includes detecting a movement of the head of the user. While the surgical control system is in the imaging control mode and responsive to the user's head movement, an image of the surgical environment from a changed field of view of the imaging instrument is displayed. The changed field of view corresponds to the detected movement of the user's head.

Minimally invasive medical techniques are intended to reduce the amount of tissue that is damaged during invasive medical procedures, thereby reducing patient recovery time, discomfort, and harmful side effects. Such minimally invasive techniques may be performed through natural orifices in a patient anatomy or through one or more surgical incisions. Through these natural orifices or incisions, clinicians may insert medical tools to reach a target tissue location. Minimally invasive medical tools include instruments such as therapeutic instruments, diagnostic instruments, and surgical instruments. Minimally invasive medical tools may also include imaging instruments such as endoscopic instruments that provide a user with a field of view within the patient anatomy. Some minimally invasive medical tools and imaging instruments may be teleoperated or otherwise computer-assisted. When performing teleoperational procedures or providing training simulations for teleoperational procedures, head-mounted display systems may be used to provide the clinician with an immersive augmented-reality or virtual reality experience. System controls are needed to provide for safe and reliable operation of teleoperational systems when using an immersive display system.

Systems and methods for constraining a virtual reality surgical system


The biphasic extraction from coffee waste without a prior drying process, to obtain coffee oil, which is transesterified with KOH catalyzed methanol to produce mixtures of glycerol free methylic esters, also known as coffee oil biodiesel, which is subjected to an aminolysis reaction with aminoethylethanolamine (AEEA) by heating to 140-160° C. at atmospheric pressure with a subsequent dehydration reaction at the same temperature but at a reduced pressure of 200 to 300 mmHg, in order to achieve cyclization of the intermediary amides into the corresponding imidazolines. Alternatively process, coffee oil can be submitted to the same aminolysis procedure with aminoethylethanolamine (AEEA) at 140 to 160° C. and atmospheric pressure with a subsequent dehydration reaction at the same temperature but at a reduced pressure of 200 to 300 mmHg, to produce imidazolines that contain the residual glycerol of the original triglycerides.

Interior corrosion in pipelines, containers and processing facilities is a serious issue that jeopardizes a safe, reliable and environmentally harmless operation of industrial processes. Most metallic materials are very vulnerable to contact with water and a variety of electrolytes. This is a particularly serious problem in the oil industry, due to the growing total salinity and acidity of primary production, which has an impact in the entire chain of transport, refining and distribution processes.
Interior corrosion in pipelines, containers and industrial facilities caused by transport, storage or processing of fluids that contain water and electrolytes can be controlled using corrosion inhibitors.
The process of adding corrosion inhibitors to hydrocarbons being transported, stored or processed has proven significantly successful in mitigating corrosion to levels below two thousands of an inch per year, a parameter that is a requirement for many regulations to ensure several decades of useful life for metallic components (Norm NRF-005-PEMEX-2009). There's a wide variety of products that serve as corrosion inhibitors, one of the most important ones is the family of compounds known as imidazolines, which inhibit corrosion in low dosages from 5 to 150 ppm, and are considered amongst the most environmental friendly substances used in the industry. 2-Alkyl-imidazolines have been used as corrosion inhibitors in the oil industry since the 1940's. These inhibitors are used as mixtures of imidazolines with a hydrocarbonated chain of 7 to 19 carbon atoms (hydrophobic group) in position two, and a polar group in position one, such as hydroxyethyl or acylaminoethyl. Imidazolines can also be quaternized to be employed as cationic surfactants, fabric softeners, hair conditioners or antistatics.
Imidazolines of the 2-(2-alkyl-4,5-dihydro-1H-imidazol-1-il)ethanol type, extracted from vegetable oils such as palm or coconut oil, or animal fats, are commercially traded for different applications. An important usage for this type of compounds is corrosion inhibition for pipelines, containers and other facilities, property of industries that transport, process and store hydrocarbons. However, obtaining or applying imidazolines derived from oils extracted from coffee waste has never been conceived before. Even when coffee oil is well-known as a source of biofuels, no other process has been reported to obtain imidazolines derived from coffee oil. Coffee waste resulting from residue left over from the preparation of coffee beverages and other coffee based products, contain between 13 and 15% (dry base) of oil, which includes linoleic acid as the most abundant fatty acid found in this oil. Linoleic acid is doubly unsaturated, conferring the imidazolines containing it a superior adherence to metallic surfaces, due to the interaction of the pi electrons of the double bonds with the electrons of the metallic surface.
Imidazolines derived from coffee oil show, besides excellent qualities as corrosion inhibitors, low toxicity and good biodegradability, which makes them a very appropriate and environmentally friendly option as corrosion inhibitors for the industry as well as being suitable for applications such as fabric softeners, antistatic agents, hair conditioners, etc.
Coffee is one of the most important agricultural products worldwide and is also one of the most popular beverages with a very high level of consumption. It is estimated that worldwide, coffee production is close to 6 million tons, with ten leading countries. Coffee consumption is varied, from 12 Kg per capita in Finland, to a general average of 1.2 kg per capita. Depending on variety, the content of oil in coffee waste fluctuates between 13-18% (dry base). Most of ground coffee bean residue is disposed of in landfills, even though it has been proposed to use it to produce compost. Coffee waste is known as a soil and water bank pollutant, due to the toxic properties of caffeine.
Coffee oil is a mixture of triglycerides constituted by fatty acids of 14 to 22 carbon atoms, with a composition of fatty acids that depends on the type and origin of the coffee. It has been reported a composition of 44% linoleic acid, 33% palmitic acid, 9% oleic acid, 7% stearic acid and other fatty acids in minor contents.
Several processes have been described for coffee oil extraction, as a starting material for biodiesel. These processes employ soxhlet equipment, supercritical CO2 for dry coffee waste, as well as ultrasound assisted biphasic extraction.
The procedures mentioned above for extraction of oil from coffee are, from our point of view, not feasible on an industrial scale, given that they require coffee that has been previously dried, as well as very costly industrial equipment, such as those that would demand the use of ultrasound or supercritical CO2.
Specialized literature shows relevant references on the history and scientific breakthroughs that support this invention: Ortega-Toledo, D. M.; Gonzalez-Rodriguez, J. G.; Casales, M.; Martinez-Gomez, L. Corrosion Science, 53, 3780-3787 (2011); Radcriffe, R. U.S. Pat. No. 2,200,815 (1940); Meyer, G. R., U.S. Pat. No. 6,448,411 (2002); Daglia, M; Racchi, M.; Papetti, A.; Lanni, C.; Govoni, S.; Gazzani, G. Journal of Agricultural and Food Chemistry, 52, 1700-1704 (2004); Barkenbus, C.; Zimmerman, A. J. Journal of the American Chemical Society 49, 2061-2064 (1927); Kondamudi, N.; Mohapatra, S. K.; Misra, M. Journal of Agricultural and Food Chemistry 56 (24), 11757-11760 (2008); Scanlan, J. U.S. Pat. No. 6,488,732 (2002); Martin, M. J. et al., Talanta, 54, 291-297 (2001); Misra, M.; Mohapatra, S. K.; Kondamudi, N. V. US 2010/0287823; Couto, R. M.; Fernandes, J.; Gomes da Silva, M. D. R.; Simoes, P. C. J. Supercritical Fluids, 51(2), 159-166 (2009); Oliveira, L. S.; Franca, A. S.; Camargos, and Ferraz, V. P. Bioresource Technology 99, 3244-3250 (2008); Abdullah, M.; Bulent Koc, A. Renewable Energy 50, 965-970 (2013); Al-Hamamre, Z.; Foerster, S.; Hartmann, F.; Kroger, M.; Kaltschmitt, M. Fuel, 96, 70-76 (2012); Khan, N. A.; Brown, J. B. Journal of the American Oil Chemists' Society, 30, 606-609 (1953); Seung-H. Yoo, Young-Wun Kim, Kunwoo Chung, Seung-Yeop Baik, Joon-Seop Kim. Corrosion Science, 59, 42-54 (2012); Rivera-Grau, L. M.; Casales, M.; Regla I.; Ortega-Toledo, D. M.; Ascencio-Gutierrez, J. A.; Gonzalez-Rodriguez, J. G.; Martinez-Gomez, L. International Journal of Electrochemical Science, 7, 12391-12403 (2012); Erik M. Quandt, Michael J. Hammerling, Ryan M. Summers, Peter B. Otoupal, Ben Slater, Razan N. Alnahhas, Aurko Dasgupta, James L. Bachman, Mani V. Subramanian, and Jeffrey E. Barrick, ACS Synth. Biol., Mar. 8, 2013; Williams C F, McLain J E, J Environ Qual. 2012 September-October; 41(5): 1473-80.
Amongst the patents reviewed to sustain the originality of the invention, patent JP2013013344 introduces a method for production of coffee oil for aromatic applications, where oil is extracted from roasted coffee beans hydrated with an oil/water emulsion using a centrifuge. This patent does not mention using the linoleic acid contained in the triglycerides present in the oil that has been extracted from coffee to obtain imidazolines, whose main quality is high adherence to metallic structures.
The patent with registration number CN 102875160 A introduces an invention related to the production of ceramic compound based additives using microwave radiation induction processes, hydroxymethylation and esterification where the raw materials are the lignosulphonates extracted from ground coffee. This patent does not describe any process related to the production of coffee biodiesel and imidazolines, such as the process of transesterification with KOH catalyzed methanol and aminolysis with aminoethylethanolamine (AEEA) respectively.
The patent with registration number US2007/0259084 A1 is related to the extraction of coffee surfactants using sugar transesterification and coffee oil, whose porpoise is the production of emulsions of this organic compound to improve coffee products, such as instant coffee, improving its aroma and taste. Likewise, this patent does not contemplate the use of coffee oil nor the processes inherent to extracting imidazolines for their use as corrosion inhibitors in the hydrocarbon industry.
The patent with registration number AR2010P100096 20100115 introduces a method to obtain biodiesel from coffee grounds. The purpose of this invention is to recycle coffee residue to produce a renewable fuel, with low environmental impact, however it makes no reference about any method or process to use organic coffee residue to inhibit interior corrosion in pipelines, containers and other industrial facilities related to storage and transport of hydrocarbons.
The patent with registration number US 2010/0287823 A1 describes a method for the production of a biofuel using one or more sources of coffee as raw material, such as green coffee grains, roasted coffee grains, ground coffee or ground coffee byproducts. This biofuel is extracted using a transesterification procedure of the triglycerides found in the coffee sources mentioned above, where the products obtained can be used for other purposes such as the production of cosmetics, drugs, food or fuel materials, however this patent does not consider an aminoethylethanolamine aminolysis (AEEA) process for the production of imidazoline mixtures.
Other patents reviewed, contemplate the production of biofuels, patents U.S. Pat. No. 8,545,702 y U.S. Pat. No. 8,540,881 B1, which are related to the production of biodiesel and/or glycerin from various processes, such as oil transesterification. These patents do not consider the use of coffee residue, nor the extraction of its oil as raw material for the production of corrosion inhibitors.
Likewise, there are patents related to obtaining imidazolines and their byproducts from chemical processes for various applications, such as processing of imidazolines of polycarboxylic acids for production of cleaning products (U.S. Pat. No. 5,049,315) imidazolines (U.S. Pat. No. 2,161,938), process for the preparation of substituted imidazoline as a fabric softener for the textile industry (U.S. Pat. No. 5,154,841). However, none of these patents make reference to the processing of coffee residue and using the linoleic acid contained in the triglycerides of the oil extracted from coffee for the synthesis of 2-alkyl-1-hidroxiethyl imidazolines which is doubly unsaturated and its main feature is high adherence to metallic surfaces.

Process to obtain mixtures of imidazolines and corrosion inhibitors from coffee waste


This invention relates to a process of reducing polyketones to polyalcohols using borohydride salts where the reducing agent is suspended in water.

The existence of copolymers of carbon monoxide with olefins, especially ethylene, is well known in the prior art. The copolymerization of ethylene and carbon monoxide using free radical initiators has been described by Brubaker et al. (U.S. Pat. No. 2,495,286) Furthermore, copolymerization of ethylene and carbon monoxide initiated by gamma-irradiation has been claimed by Columbo et al. in Journal of Polymer Science, Part Al, Vol. 4 (1966) p. 29. These methods produce polymers with carbon monoxide contents ranging from less than 1% to as much as 50%.
Linear alternating copolymers and terpolymers of carbon monoxide and .alpha.-olefins, especially ethylene (ECO), having the general formula [--(CO) (ol)-].sub.n, where ol are .alpha.-olefin monomers, have been prepared using transition metal complexes as described by Nozaki (U.S. Pat. No. 3,694,412), Fenton (U.S. Pat. No. 4,076,911), Lai and Sen (Organometallics, Vol. 3 (1984) p. 866) and Drent (U.S. Pat. Nos. 4,818,810 and 4,835,250).
Reduction of .alpha.-olefin-carbon monoxide copolymers produces polyalcohols. Polyalcohols can be cast or extruded into films and used as adhesives or coatings for paper. Polyalcohols also show a a high degree of barrier properties. This is of advantage in packaging for food, drug and cosmetics, which usually undergo oxidative degradations when exposed to air.
Polyalcohols such an ethylene-vinyl alcohol (EVOH) are generally produced by hydrolysis of ethylene-vinyl acetate copolymers (EVA), not reduction of .alpha.-olefin copolymers. Polyalcohols produced from .alpha.-olefin-carbon monoxide copolymers have a number of advantages over EVOH produced from the hydrolysis of EVA. These are:
1) carbon monoxide is a less expensive feedstock than vinyl acetate; PA0 2) hydrolysis of EVA to EVOH results in the formation of acetate salts as byproducts (actate salt byproduct are not formed when .alpha.-olefin CO copolymers are reduced); PA0 3) Reduction of linear, alternating .alpha.-olefin-carbon monoxide copolymers produces polyalcohols of highly regular structures (EVOH produced by the hydrolysis of EVA does not produce highly regular structures); PA0 4) polyalcohols made by the reduction of alternating ECO copolymers have a greater density of hydroxyl groups (I) than EVOH made from EVA (II):
I Fig. A. (--CH.sub.2 --CH.sub.2 --CH(OH)--).sub.n PA1 II. Fig. B. (--CH.sub.2 --CH.sub.2 --CH.sub.2 --CH(OH)--).sub.n.
Furthermore, polyalcohols represented by formula I from alternating ECO copolymers have high molecular purity and higher stability than those represented by formula II due to the structural inability of polyalcohols represented by formula I to dehydrate to conjugated dienes, as those represented by formula II are known to do.
Two principal methods have been used for the reduction of these carbon monoxide copolymers to polyalcohols. One is hydrogenation using a transition-metal catalyst. Brubaker et al. (Journal of the American Chemical Society, Vol. 74 (1952) p. 1509) and van Broekhoven (U.S. Pat. No. 4,929,701) describe the use of copper chromite or nickel catalysts to reduce polyketones to polyalcohols. However, the high temperatures and pressures used in this process can result in dehydration of CO-rich copolymers to 2,5-tetrahydrofurandiyl functionalities, which have inferior barrier properties. Furthermore, Wong et al. in European Patent Application 0 322 976 (1988) teach the hydrogenation of polyketones using nickel salts reacted with borohydrides as catalysts.
It is, of course, well known that borohydride salts can be used to reduce ketones to alcohols under mild conditions. There are a number of examples in the prior art of the reduction of polyketones like ECO by borohydride salts. JP 82-015907-B4 uses hydrogenated boron sodium, presumably sodium borohydride. Morashima et al. (European Polymer Journal, Vol. 9 (1973) p. 669) also used sodium borohydride in methanol. Wong et al. (European Patent Application 0 322 976) and Wong (U.S. Pat. No. 4,868,254) prefer reductions of .alpha.-olefin-carbon monoxide copolymers by sodium borohydride in hexafluoroisopropanol or m-cresol.
All these examples imply or teach that polyketone reductions by borohydride require the use of alcoholic media so that the starting polyketone and/or the product polyalcohol may dissolve. There are a number of disadvantages, however, in carrying out these reactions in alcohols. Common borohydride salts such as sodium borohydride react with alcohols to form tetraalkoxy- or tetraaryloxyborates. This type of decomposition is particularly rapid in methanol. Ethanol or isopropanol react more slowly with sodium borohydride, but the solubility of the borohydride in these solvents is low (respectively 4 and 0.25 grams per 100 ml of solvent), resulting in large amounts of effluent after the reduction. Other solvents, such as hexafluoroisopropanol or m-cresol, are toxic and expensive.
In light of the deficiencies described, the need for an improved process for the reduction of .alpha.-olefin-carbon monoxide copolymers and terpolymers which uses an inexpensive, non-toxic solvent in which the reducing agent is both highly soluble and stable is deemed readily apparent.

Reduction of .alpha.-olefin-carbon monoxide copolymers to polyalcohols with borohydride salt


In one aspect of the invention, each bolt is modeled using a beam element in a FEA model. To apply desired pretension to one or more bolts, at least one pretension-versus-time curve is specified. Each pretension-versus-time curve includes ramp portion, desired pretension portion and optional unloading portion. Duration of the pretension-versus-time curve generally covers first 0.5-1% of total simulation time of a car crashworthiness analysis. Ramp portion starts from zero to desired pretension in a substantially linear manner, and hence being configured for applying desired pretension to a bolt gradually with smaller increments. Desired pretension portion is configured for ensuring the desired pretension can actually be applied to the beam element during an initialization process—a series of quasi-static analyses. Since the method is independent of the deformation of the beam, the method completely avoids the need to iteratively determine an axial strain or displacement that gives the desired pretension.

Finite element analysis (FEA) is a computer implemented method widely used in industry to model and solve engineering problems relating to complex systems such as three-dimensional non-linear structural design and analysis. FEA derives its name from the manner in which the geometry of the object under consideration is specified. With the advent of the modern digital computer, FEA has been implemented as FEA software. Basically, the FEA software is provided with a model of the geometric description and the associated material properties at each point within the model. In this model, the geometry of the system under analysis is represented by solids, shells and beams of various sizes, which are called elements. The vertices of the elements are referred to as nodes. The model is comprised of a finite number of elements, which are assigned a material name to associate with material properties. The model thus represents the physical space occupied by the object under analysis along with its immediate surroundings. The FEA software then refers to a table in which the properties (e.g., stress-strain constitutive equation, Young's modulus, Poisson's ratio, thermo-conductivity) of each material type are tabulated. Additionally, the conditions at the boundary of the object (i.e., loadings, physical constraints, etc.) are specified. In this fashion a model of the object and its environment is created.
FEA is becoming increasingly popular with automobile manufacturers for optimizing both the aerodynamic performance and structural integrity of vehicles. Similarly, aircraft manufacturers rely upon FEA to predict airplane performance long before the first prototype is ever developed. One of the popular FEA tasks is to simulate an impact event such as car or truck crashworthiness. A problem associated with crashworthiness simulation is to properly simulate bolted joints or connections between two parts especially in trucks.
General purpose of a bolted joint is to clamp two or more parts together. The clamping force is achieved by applying torque to the bolt head and the nut; the mechanical advantage of the wrench and threads allows one to actually stretch the section of the bolt between the head and the nut (an area known as the grip), creating tension in the bolt. This tension is known as pretension because it exists before any other forces are applied to the joint. The pretension is transmitted to the mating parts through the head, nut, and any washers that may be present. It squeezes the mating parts together, and if the joint is designed, assembled, and maintained properly, prevents the mating parts from separating or sliding under normal loads.
Pretension needs to be simulated realistically in order to simulate bolted joints or connections properly in a finite element analysis. Many prior art approaches are cumbersome and/or tedious for users not only in creation of the FEA model, but in actual simulation itself. In one example, a prior art approach requires users to specify each bolt with a predefined axial stretch. This can be accomplished is a number of ways, for example, including the use of a thermal gradient to create the stretch or simply setting the axial stress value corresponding to the predefined stretch. Since typical FEA models may contain hundreds of bolts in close proximity, the interactions that result leave many bolts with inaccurate pretensions. During the initialization stage of a simulation, users must pay special attention to ensure that the correct pretension is indeed achieved in each and every one of the bolts in the FEA model. This prior art approach may work when there are very limited number of bolts provided these bolts are not located in substantially different orientations. In another prior art approach, each bolt is represented by a beam element, whose axial stress is iteratively determined by prescribing the motion of two beam end nodes. When the desired axial stress is reached, constraints would then be introduced and used to create a rigid link between the two beam end nodes. The primary reason for bolt pretension not reaching the desired level is due to deformation of the plates or other components within the bolted joints. In another example, a very detailed bolt model may be required (e.g., a number of solid elements) to ensure pretension as internal stress.
Therefore, it would be desirable to have an improved method of initializing bolt pretension in a finite element analysis.

Method of initializing bolt pretension in a finite element analysis

Livermore Software Technology Corporation


An exposure apparatus generates an interlock signal to stop an exposure process when defocus is detected in real time. Leveling data for at least one wafer, and a predetermined threshold value are stored in a memory of the exposure apparatus. A value indicative of the defocus is calculated from the leveling data. An interlock signal is generated if the result of comparing the defocus value and the threshold value reveals that the focus of a lens of the exposure apparatus is outside an acceptable range.

1. Field of the Invention
The present invention generally relates to a semiconductor manufacturing apparatus. More particularly, the present invention relates to an exposure apparatus of photolithographic equipment.
2. Description of the Related Art
Photolithography is used to form a fine circuit pattern on a wafer. A photolithographic process generally includes cleaning the surface of a wafer, coating the surface with photoresist, aligning the wafer with a mask or reticle, exposing the layer of photoresist to light directed through the mask or reticle, and developing the exposed layer of photoresist. The alignment and exposure processes are carried out using an exposure apparatus.
In addition to a mask or reticle, an exposure apparatus includes a light source, a light measuring device, and a stage on which the wafer is supported. Such exposure apparatus for use in manufacturing a semiconductor device are generally classified as a contact type, a proximity type, or a projection type of exposure apparatus. Projection-type exposure apparatus may further be classified as those comprising an aligner, a stepper, or a scanner. The stepper and scanner each employ a reduction projection type of exposure system, and an aligner employs an iso-magnification projection type of exposure system.
All exposure apparatus must provide a high degree of resolution, and their optics must be able to precisely focus a pattern of light onto a wafer. To this end, a stepper emits light onto a wafer through a reticle while the wafer is stationary. On the other hand, a scanner performs an exposure process while a reticle and a wafer are moving at a uniform speed. Furthermore, the stepper uses refraction optics, whereas the scanner uses reflection optics and a slit. Also, the useful area of the lens in a scanner is very small compared to that of the lens of a stepper. Thus, a scanner is less influenced by aberrations of the lens than a stepper, and a larger numerical aperture (NA) is available in a scanner. Still further, the exposure area is larger in a scanner, which facilitates the reproducibility of the exposure process.
Hence, the current trend is to move away from using a stepper. Instead, exposure apparatus comprising scanners have become more widely used. As chips become larger and semiconductor devices become more highly integrated, the next generation of exposure apparatus will be able to expose wafers over even larger fields.
Nonetheless, an improper calibration of an exposure apparatus or a rapid change in scanning direction may cause a defocus to occur in the exposure process. Such a defocus problem and a conventional method to solve the problem will be described below referring to FIGS. 1A, 1B and 2.
FIG. 1A illustrates an exposure apparatus 10 for use in manufacturing a semiconductor device according to the prior art. FIG. 1B is a table of leveling data generated during an exposure process carried out by the exposure apparatus 10.
Exposure apparatus 10 includes a reticle 1, a light source 2 that emits light through the reticle 1, a reticle stage 3 on which the reticle 1 is mounted, a lens 4 by which light passing through reticle 1 is focused onto a desired portion (shot) of a wafer 5 coated with a layer of photoresist, a level detector 6 for sensing information pertaining to the position/configuration of a surface of the wafer, a wafer stage 8, and a wafer stage position controller 7 to control the position of a wafer stage 8. Leveling data for a wafer is generated by the level sensor 6 during an exposure process, and is discarded after the exposure process.
In FIG. 1B, the squares represent respective shots on a wafer, and the data within each square includes the leveling data measured during the exposure process for the respective shot. Reference numeral 11 indicates data identifying the shot by number. Reference numeral 12 indicates data representative of the relative height of a surface of the wafer for the respective shot. Reference 13 indicates data representative of the degree to which the surface is inclined relative to the horizontal for the respective shot, and reference numeral 14 indicates data representative of the progression of the scan in forward or reverse directions (up or down directions in the figure)and a value representing the degree to which the lens 4 was out of focus prior to exposing the shot (focus error).
That is, to scan the pattern of a reticle onto a respective portion (shot) of the wafer 5, the wafer 5 is scanned by moving the lens 4 in one of two opposite scanning directions referred to hereinafter as downward and upward directions. A scan by the lens 4 in one of the directions will be referred to as a down scan, and a scan by the lens 4 in the other of the directions will be referred to as an up scan. Furthermore, a shot exposed using a down scan of the lens will be referred to as a down scan shot, and a shot exposed using an up scan of the lens 4 will be referred to as an up scan shot. In FIG. 1B reference "U" denotes an up scan shot, and reference "D" denotes a down scan shot.
A critical dimension (CD) of the pattern formed on the wafer 5 is measured to determine whether the circuit pattern on reticle 1 has been properly transferred to the wafer 5. If the pattern formed on the wafer 6 has a CD outside of a desired range, the lens 4 is checked to determine whether it has drifted out of focus.
More specifically, and again referring to FIGS. 1A and 1B, the lens 4 may drift out of focus between an up scan and a down scan. However, it is difficult to determine from the leveling data whether the lens 4 is out of focus. Furthermore, as was mentioned above, the leveling data is temporarily stored in the exposure apparatus 10 and is then discarded. Therefore, the exposure process must be stopped, and a specific leveling qualification test (LQT) must be performed using the leveling data to determine whether the lens 4 is out of focus.
FIG. 2 is a flowchart illustrating an LQT using the leveling data shown in FIG. 1B.
With reference to FIG. 2, a critical dimension (CD) measuring device checks whether the CD of an actual pattern formed on a wafer exceeds the desired or design CD (S21). If the measured CD is acceptable, an exposure process is performed (S27) on the next wafer. However, if the measured CD exceeds a certain value, the exposure process is stopped (S22), and then an LQT using leveling data is executed (S23). The result of the LQT, i.e., the value of the defocus, is outputted to a display device (S24). At this time, if the defocus exceeds a threshold value (S25), the focus of the lens 4 is re-calibrated (S26) and then, the next exposure process is performed (S27). On the other hand, if the value of the defocus is below the threshold value, the next exposure process is performed.
A disadvantage with this method is that the exposure process must be stopped to detect whether the lens is out of focus, and then the level qualification test must be performed. The stopping, the testing, and the re-starting detract from the productivity of the overall process of manufacturing the semiconductor devices.

Exposure apparatus and method of controlling exposure apparatus


A method of forming a resist pattern comprises the following steps. A resist is applied on a wafer for subsequent baking the same. Subsequently, the resist-applied wafer is then stored in an atmosphere maintained at a humidity of not less than 80% until the resist-applied wafer is placed in an exposure system for exposure thereof by use of a photo-mask. A development of the exposed resist on the wafer is carried out to form a resist pattern. It is possible to further store the wafer in a clean room before the exposure. The above resist is preferably a chemical sensitizing resist.

The present invention relates to a method of forming a resist pattern in a micro-lithography technique.
In recent years, as the semiconductor devices have been scaled down increasingly, the stability of micro-lithography technique and uniformity of the resist pattern have been required. In the micro-lithography processes, a resist is first applied on a semiconductor wafer for subsequent baking thereof before an exposure of the baked resist is carried out by use of a described photo-mask pattern such as reticle. Subsequently, the exposed resist is baked and the development thereof is then carried out to thereby form a photo-resist pattern. The photo-resist pattern is then used as a mask for etching the wafer before the used photo-resist pattern is removed. In such photo-lithography processes, the exposure system is most expensive, for which reason it is required to increase the rate of operation of the exposure system. In order to satisfy this requirement, the number of resist application systems is increased so that resist can be applied fast for subsequent exposure treatment by the exposure system without any rest. Such production management has the following difficulty. The number of wafers to be processed in one time is likely to be different for every system. In this case, it is conventional to temporarily store the wafers applied with resist in a wafer storage buffer provided between the resist-application system and the exposure system for subsequent supply thereof into the exposure system. It was found that the storage of the resist-applied wafer in the wafer storage buffer after the resist was applied to the wafer and before the resist-applied wafer will be exposed may cause a variation in scale of the resist pattern. The variation in scale of the resist pattern might depend upon the time of storage of the resist-applied wafer in the wafer storage buffer.
At present, a chemical sensitizing negative resist is generally used. The size of the chemical sensitizing negative resist was measured with reference to variation in storage time "Th" during which the resist-applied wafer is stored in the wafer storage buffer after the resist-applied wafer was baked until the stored resist is then placed into the exposure system, provided that a time from the resist exposure until the development is fixed. The wafer is stored in a standard atmosphere in the clean room. The exposure conditions are selected under which if the storage time is zero, the size of the resist pattern corresponds to the designed size. The result of measurement is shown in FIG. 1, from which it can be understood that as the storage time Th becomes long, then the resist pattern size becomes reduced until the storage time Th becomes 40 minutes.
The storage time from baking the exposed wafer until the development thereof relates to the degree of influence to the variation in size of the resist pattern. The resist is made of an organic material, for which reason an atmosphere in the resist-application system chamber is almost 100%-organic atmosphere but no moisture is present. The resist-applied wafer will have received a certain influence by humidity when the resist-applied wafer is pull out of the resist-application system. The moisture is taken into the resist in the moisture rich atmosphere. Particularly, the moisture content in the resist is certainly increased when the resist will have been stored in the wafer storage buffer.
If the size of the resist is once varied by absorbing the moisture in the storage time duration between baking the resist-applied wafer and the exposure thereof, then the size of the resist pattern is then also varied from the designed value. Particularly if the line width of the resist pattern is in the sub-half micron order or not more than 0.25 micrometers, then the chemical sensitizing resist is preferably used in the light of sensitivity and resolution. Notwithstanding, the chemical sensitizing resist is likely to vary in size largely by absorbing the moisture, for which reason the line width of the resist pattern is varied by only 0.05 micrometers. This however means that 20% variation in size thereof appears if the line width of the resist pattern is in the sub-half micron order or 0.25 micrometers.
Against the above problems, it is required to do a strict management of the temperature and humidity around the resist. A method of maintaining the resist-applied wafer at predetermined temperature and humidity is disclosed in the Japanese laid-open patent publication No. 4-326509. A central control system or a process control box is provided on the resist process line for controlling the temperature and humidity around the resist-applied wafer in the stand-by state in the wafer storage buffer. The Japanese laid-open patent publication No. 4-326509 does not mention how to control the temperature and humidity around the resist-applied wafer stored in the wafer storage buffer, for which reason it is difficult to apply the above prior art practically. Normally, the clean room is maintained at a temperature in the range of 23-25.degree. C. and at a humidity of about 45%. If the resist-applied wafer is placed in the clean room for the purpose of storage thereof, then the temperature and humidity are well controlled and maintained stable. Accordingly, it is considered that variations in temperature and humidity of the atmosphere is well suppressed in the clean room so that the variation in size of the resist pattern caused by variation in the content of the moisture in the resist is well suppressed even if the resist-applied is stored in the clean room. The above prior art needs to use large scale equipment such as the central control system and the process control box for controlling the temperature and humidity of the atmosphere around the resist-applied wafer stored in the wafer storage buffer, for which reason the above prior art is costly.
In the above circumstances, it had been required to develop a novel method of forming a resist pattern free from any variation in size thereof and applicable to a sub-half micron photolithography process without any increase in the equipment cost.
The present invention provides a method of storing a resist-applied wafer having been baked until an exposure thereof by use of a photo-mask, wherein the resist-applied wafer is placed in an atmosphere maintained at a humidity of not less than 80%. It is preferable that the resist-applied wafer is placed in an atmosphere maintained at a temperature not lower than the room temperature for at least about 10 minutes. It is also preferable that the resist-applied wafer is placed in an atmosphere maintained at a humidity of not less than 90% for at least about 5 minutes. It is possible to further store the wafer in a clean room before the exposure.
The present invention also provides a method of forming a resist pattern which comprises the following steps. A resist is applied on a wafer for subsequent baking the same. Subsequently, the resist-applied wafer is then stored in an atmosphere maintained at a humidity of not less than 80% until the resist-applied wafer is placed in an exposure system for exposure thereof by use of a photo-mask. A development of the exposed resist on the wafer is carried out to form a resist pattern. It is possible to further store the wafer in a clean room before the exposure. The above resist is preferably a chemical sensitizing resist.