An embodiment of a method for detecting low frequency occurrence of one or more HIV sequence variants associated with drug resistance is described that comprises the steps of: generating cDNA species from each RNA molecule in an HIV sample population; amplifying at least one first amplicon from the cDNA species, wherein each first amplicon comprises a plurality of amplified copies and is amplified with a pair of nucleic acid primers that define a locus of the first amplicon; clonally amplifying the amplified copies of the first amplicons to produce a plurality of second amplicons wherein a plurality of the second amplicons comprise an immobilized population of substantially identical copies from one of the amplified copies of first amplicons; determining a nucleic acid sequence composition of the substantially identical copies from at least 100 of the immobilized populations in parallel on a single substrate; and detecting one or more sequence variants that occur at a frequency of 5% or less in the nucleic acid sequence composition of the at least 100 immobilized populations; and correlating the detected sequence variants with variation associated with HIV tropism.

The Human Immunodeficiency Virus (generally referred to as HIV) continues to be a major problem worldwide, even though a plethora of compounds have been approved for treatment. Due to the error-prone nature of viral reverse transcriptase and the high viral turnover (t½=1-3 days), the HIV genome mutates very rapidly. For example, reverse transcriptase is estimated to generate, on average, one mutation per replication of the 9.7 Kb genome that does not dramatically affect the ability of the virus to propagate. This leads to the formation of 'quasispecies', where many different mutants exist in a dynamic relationship.
HIV virus particles enter cells via the CD4 receptor and a co-receptor molecule. The co-receptor specificity of a given viral particle determines its tropism (The term "tropism" generally refers to the affinity of a viral particle for particular cell and receptor types). The majority of HIV-1 strains utilize the chemokine receptors CCR5 (R5 tropism), CXCR4 (X4 tropism) or both (R5X4 or dual tropism). Most newly infected individuals appear to have predominantly R5 tropic virus, and the SI phenotype has been associated with late-stage HIV infection and low CD4 cell counts as well as accelerated progression to AIDS. Additional examples of HIV tropism strains and their relationship to disease progression are described in Poveda et al., AIDS 2006, 20:1359-1367; Jensen et al., AIDS Rev 2003; 5:104-112; Jensen et al., Journal of Virology May 2006, p. 4698-4704; Jensen et al., Journal of Virology, December 2003, p. 13376-13388; and Nelson et al., Journal of Virology, November 1997, p. 8750-8758, each of which is hereby incorporated by reference herein in its entirety for all purposes.
There is currently only one FDA-approved drug that inhibits HIV entry by disrupting its interaction with a co-receptor, but more are in development. Maraviroc (also known as Selzentry, which is marketed by Pfizer Inc.) is a small molecule CCR5 inhibitor. Current recommendations published by the FDA state that each patient's HIV population be tested for tropism before Maraviroc is prescribed. This is due to the fact that clonal analysis of HIV quasispecies in patients that failed treatment during Maraviroc clinical trials revealed that small amounts of X4 tropic viruses were present before treatment initiation and it is thought that selection against CCR5 entry gave the X4 virus an advantage over the majority R5 strains. This mode of resistance development is analogous to the emergence of resistance to the 'classical' HIV drugs, i.e, protease and reverse transcriptase inhibitors, where a significant subset of HIV infected subjects carry pre-existing resistant strains prior to drug exposure—most likely due to primary infection by exposure to virus from treatment-experienced individuals. In addition to this pathway, resistant strains are continually generated de novo from wild type virus by replication under drug selective pressure due to the error-prone nature of the viral reverse transcriptase as described above. However, outgrowth of pre-existing resistant or, in the case of maraviroc treatment, X4 tropic virus, is more efficient under drug treatment and leads to accelerated treatment failure.
Viral tropism is determined by exposed amino acid sequences in the gp120 surface envelope protein. In particular, the V3 (third variable) region has been implicated in co-receptor usage selection. As the name implies, the approximately 35 amino acid long sequence is highly variable, but there are common features distinguishing R5 and X4 tropic viruses located within this sequence. A number of tropism prediction algorithms have been developed based directly on V3 sequences, and these are likely to be continually refined over the next few years. For example, several position specific scoring matrix (PSSM) algorithms that directly correlate amino acid residues in the V3 to tropism phenotypes (as well as these can be determined) have been published and some can even be accessed through the Internet.
Phenotypic tropism testing is now commercially available, but is expensive, labor intensive and time consuming. Additionally, phenotyping is heavily dependent on the efficient generation of a library of viral sequences, such that any cloning bias will generate a systematic testing error. Both phenotypic and sequence-based tropism determination is currently performed as population assays, which are, by their nature, less sensitive than assays based on clonal separation of each viral strain. However, clonal analysis is extremely labor intensive and requires testing of thousands of clones from each subject in order to achieve high sensitivity. Embodiments of the described invention include a sequence-based tropism determination assay wherein clonal sequences are obtained directly from viral RNA quasispecies without a labor intensive cloning step. Long read-length 454 sequencing available from 454 Life Science Corporation is ideally suited to generating thousands of clonal reads from multiple subjects in a single sequencing run. Further, embodiments of the described sequencing technologies enable what may be referred to as "Massively Parallel" capable of achieving a sensitivity of detection of low abundance variants that include a frequency of 1% or less of the allelic variants in a population. This, coupled with a tropism prediction algorithm provides a convenient method for quickly and efficiently obtaining tropism information at very high sensitivity.

System and method for detection of HIV tropism variants


Laundry detergent compositions comprising C.sub.12 -C.sub.14 dimethyl hydroxyethyl quaternary ammonium cationic surfactants in combination with certain modified polyamines which provide increased fabric cleaning benefits.

Detergent formulators are faced with the task of devising products to remove a broad spectrum of soils and stains from fabrics. Chemically and physico-chemically, the varieties of soils and stains ranges the spectrum from polar soils, such as proteinaceous, clay, and inorganic soils, to non-polar soils, such as soot, carbon-black, by-products of incomplete hydrocarbon combustion, and organic soils. Detergent compositions have become more complex as formulators attempt to provide products which handle all types concurrently.
Formulators have been highly successful in developing traditional dispersants which are particularly useful in suspending polar, highly charged, hydrophilic particles such as clay. As yet, however, dispersents designed to disperse and suspend non-polar, hydrophobic-type soils and particles have been more difficult to develop. Surprizingly, it has recently been discovered that the .modified polyamines of the present invention are capable of mediating the re-depositon of non-polar soils
In addition, a wide variety of soil release agents for use in domestic and industrial fabric treatment processes such as laundering, fabric drying in hot air clothes dryers, and the like are known in the art. Various soil release agents have been commercialized and are currently used in detergent compositions and fabric softener/antistatic articles and compositions. Such soil release polymers typically comprise an oligomeric or polymeric ester "backbone".
Soil release polymers are generally very effective on polyester or other synthetic fabrics where the grease, oil or similar hydrophobic stains spread out and form a attached film and thereby are not easily removed in an aqueous laundering process. Many soil release polymers have a less dramatic effect on "blended" fabrics, that is on fabrics that comprise a mixture of cotton and synthetic material, and have little or no effect on cotton articles. The reason for the affinity of many soil release agents for synthetic fabric is that the backbone of a polyester soil release polymer typically comprises a mixture of terephthalate residues and ethyleneoxy or propyleneoxy polymeric units; the same materials that comprise the polyester fibers of synthetic fabric. This similar structure of soil release agents and synthetic fabric produce an intrinsic affinity between these compounds.
It has now been surprisingly discovered that in addition to the ability to mediate hydrophobic soil redeposition, certain polyamines act in concert with selected cationic surfactants to provide increase fabric soil removal, especially from cotton fabrics. This increased soil removal benefit has been found to be independent of the type of soil present on the cotton fabric.
The modified polyamine/cationic surfactant combinations of the present invention have the increased benefit of being compatible with hypochlorite and oxygen "peracid" bleaching agents. This is especially important in the area of surface active agents that are effective on non-colored cotton fabric. The hydrophilic cellulosic composition of cotton fabric presents a surface that is not compatible with the traditional polyester terephthalate-based soil release agents. Indeed, the polyamines of the present invention themselves exhibit a propensity for attachment to the surface of the cotton fabric.
The C.sub.12 -C.sub.14 dimethyl hydroxyethyl quaternary ammonium salts which serve as cationic surfactants for the purposes of the present invention, combine with the modified polyamine surface agent/dispersents to remove soils from fabric surfaces. This combination of materials also acts to prevent redeposition of soil by holding the soil suspended in the laundry liquor which is removed prior to rinsing.
It is a purpose of the present invention to provide laundry detergent compositions which combine C.sub.12 -C.sub.14 dimethyl hydroxyethyl quaternary ammonium cationic surfactants with modified polyamine dispersants.
It is a further object of the present invention to combine the C.sub.12 -C.sub.14 dimethyl hydroxyethyl quaternary ammonium cationic surfactant and polyamine dispersents with non-cotton soil release agents. This combination of ingredients provides a soil release benefit to all laundered fabric as well as the increase in cleaning capacity.
It is yet a further purpose of the present invention to provide a bleach stable cationic surfactant/polyamine dispersent composition.
A further purpose of the present invention is to provide a method for laundering soiled fabric which comprises the step of contacting the soiled fabric, especially cotton, with a laundry detergent composition containing C.sub.12 -C.sub.14 dimethyl hydroxyethyl quaternary ammonium cationic surfactants and the disclosed polyamines.

Laundry detergent compositions comprising cationic surfactants and modified polyamine soil dispersents


A multifunction machine selects a desired software component from a list of software components accumulated in a server, acquires the selected software component and authentication information from the server, and controls the processing operation of the software component based on the acquired authentication information.

Conventionally, a printer, a copier, and a facsimile have been generally provided as discrete devices. Recently, there is known an image formation apparatus in which functions of the above-mentioned devices are accommodated into one cabinet (hereafter called "multifunction machine").
This multifunction machine has a display section, printing section, and an image pickup section within one cabinet, and also has software corresponding to a printer, copier, and a facsimile device. Switching the software allows the machine to operate as the printer, copier, or the facsimile device.
If such a multifunction machine is available, the cost and space can be in total reduced, because, there is no need to separately provide the printer, the copier, and the facsimile device.
However, such multifunction machines are generally delivered to a client after pre-installing desired softwares that perform predetermined functions. Therefore, the important matter is how to adequately update the existing functions or add new functions after the multifunction machine has been delivered.
For example, when a technology of downloading software from a server through a network and executing it on a multifunction machine is employed, it is necessary to avoid downloading of malicious software from an unauthorized server and to refuse an access request to software from an unauthorized terminal that impersonates an authorized multifunction machine.
Even if a copier is authorized, it is not appropriate to permit the copier to execute any functions other than functions previously contracted. Further, even if the functions are previously contracted, it is not worth downloading the functions (software) if they are useless from the viewpoint of a hardware configuration of the copier Based on these facts, it is important to legitimately and efficiently acquire and execute software adequate for a multifunction machine after the multifunction machine is activated.

Image formation system, software acquisition method, and computer product


A slideable armrest, which may form a lid of a vehicle console compartment, comprises a cover and a base slideably connected to each other by slideable engagement between at least one guide and at least one guide groove.

The present invention relates to an armrest, and more particularly, to an armrest that forms a part of a console compartment in a vehicle, such as in an automobile between bucket seats.
Vehicle interior components are increasingly including convenience items for vehicle operators and passengers. Center consoles located between seats are a typical accessory that may include a storage compartment with its lid being also used as an armrest. As the seats may be adjusted in a forward-to-rearward direction, it is desirable for the armrest to provide similar adjustment.
An example of a slideable armrest is illustrated and discussed in U.S. Pat. No. 6,419,314, the entire disclosure of which is hereby incorporated by reference. In the '314 patent, a cover assembly of a console compartment is also used as an armrest. The cover assembly includes a cover for an arm to rest thereon and a base for openable covering the compartment. The cover and the base are connected together by a U-shaped slide assembly so that the cover can slide relative to the base by the guiding rods provided in the slide assembly. However, the cover assembly in '314 patent comprises many components and is complicated in structure, implying a high cost in both manufacturing and assembling.
Therefore, there is a need for an improved slideable armrest that is simple in structure and therefore is of low cost in both design and manufacturing, and easy to assemble as well.


Operating code fixes are supplied to multiple processors utilizing the same operating code by storing the correction code fixes in a central RAM, and distributing the code fixes over a dedicated code fix bus to a local cache for each processor. The first processor encountering a code fix requests the code fix from the RAM, which then distributes the code fix over the code fix bus to all of the local caches which are automatically updated with the new code. The system is particularly applicable to an integrated circuit having multiple processors fabricated on a chip, wherein the RAM is on-chip and is connected to an off-chip EEPROM that loads corrected code fixes to the on-chip RAM at power-up.

1. Field of the Invention
The present invention relates generally to a multiprocessor code fix using a local cache, and more particularly pertains to a multiprocessor code fix system and method wherein operating code fixes are supplied to the multiple processors which utilize the same operating code by storing the correction code fixes in a central RAM, and distributing the code fixes over a dedicated code fix bus to a local cache for each processor.
2. Discussion of the Prior Art
As ASICs (Application Specific Integrated Circuits) have become larger and more complex, the use of ASICs in microprocessors and other programmable logic has become more common. The code or software that is used to control these programmable devices must be stored in memory during functional operation. The memory used for the storage of the code can be either RAM (Random Access Memory), ROM (Read-Only Memory) or NVRAM (Non-Volatile RAM). Each of these memory structures has its advantages and disadvantages for storage of the operation code. RAM memory allows the user to change the code at any time after manufacturing, however the code still needs to come from somewhere at power-up time since it disappears after each powering off. ROM memory is the smallest and requires the least power to run, however since the code storage is created during manufacturing it is not able to be changed afterward. Thus a bug or problem in the code means that the ASIC must be thrown away. NVRAM memory compromises between RAM and ROM and allows the code to be written into it after manufacturing but retains the code even when no power is applied to the circuit. Unfortunately, the size, speed, and manufacturing cost of nonvolatile RAM is not competitive with ROM and RAM.
FIG. 1 illustrates one practical prior art solution to this code storage problem which uses ROM for the majority of storage, and then place breaks in the code between sections of code that check in a RAM storage area to see if the next section of code is valid. The RAM is loaded at power up from an off chip EEPROM (Electronically Erasable/Programmable ROM). The ROMs inside the ASIC contain jump tables for each section of code. When the ROM reads the first section of code, it is told to jump to a location in the RAM. If the code is OK, the RAM simply sends back a return statement and the code is executed from the ROM.
If, however, there is a bug in the ROM code, as illustrated at addresses/locations 0x100C and 0x1010 which contain bad code, when the ROM reads the first section of code at address 0x1008, and is told by instruction JUMP 0x0FEC to jump to address 0x0FEC in the RAM. The RAM contains the fixed code at the next addresses 0x0FF0, 0xOFF4, 0x0FF8, and thus the processor runs from the new code in the RAM until the end of the section at address 0x0FFC, where the RAM gives the return command to JUMP 0x01024, and execution resumes from address 0x1018 in the ROM. The drawbacks to this method are that it takes time at each powerup for the RAM to load in the fixed code from the EEPROM.
The solution of FIG. 1 optimizes the use of ROM (the smallest and least power usage memory), and uses the smallest amount of RAM requiring loading from power-up. This solution also allows for the possibility that no code changes are needed and no RAM loading required. However, it requires that a small amount of processing time is used for checking the validity, and a small amount of storage space is used for the branching code. One problem is determining the granularity of the breaks and the amount of RAM included in the design. This granularity and RAM storage must be predicted before manufacturing and with no knowledge of the extent of the problems present in the code.
The solution of FIG. 1 works well given the limitations of technology, however as the number of processors on a chip increases, as in chips used in internet processors for example, the amount of RAM for fixes increases and the amount of time or buses required to load the RAM at power-up increases. A typical group of four processors (a square works best since it uses minimal space) requires four times the resources for the bug fixes. If four of these processor groups are then further grouped, the resource demand increases by sixteen.
From a software perspective, there is an additional factor in the use of more processors. Sixteen processors with independent code require sixteen times the software effort. What is effective in many applications is to duplicate the code in all of the processors and to use these processor groups as processing engines for multiple channels of data. For example, a modem can use multiple processors to handle multiple communication channels. This approach limits the amount of software effort required to take advantage of the use of multiple processors.
The problem of code fixes now becomes a case of the same fixes being duplicated over each processor. (The use of a single ROM for the processor becomes intractable as the number and speed of processors increases).

Multiprocessor code fix using a local cache

International Business Machines Corporation


A heat sink assembly (100) includes a fastening device (20) and a heat sink (10). The fastening device includes a sleeve (24), a pin (22) received in the sleeve and a biasing means (26) disposed around the sleeve. The sleeve includes a locking portion (246) formed at a bottom end thereof. The pin includes an engaging portion (226) formed at a bottom end thereof. At least a slot (248) is defined through the locking portion of the sleeve (24). The engaging portion extends outwardly through the slot and resiliently abuts against a bottom surface of the heat sink. The biasing means is slightly deformed between a top end of the fastening device and a top surface of the heat sink, thereby keeping the fastening device in a vertical position with respect to the heat sink.

1. Field of the Invention
The present invention relates generally to a heat sink assembly, and particularly to a heat sink assembly incorporating at least one fastening device which can conveniently mount a heat sink of the heat sink assembly to a heat generating electronic component.
2. Description of Related Art
As computer technology continues to advance, electronic components such as central processing units (CPUs) of computers are being made to provide faster operational speeds and greater functional capabilities. When a CPU operates at a high speed in a computer enclosure, its temperature increases rapidly. It is desirable to dissipate the generated heat of the CPU quickly, for example, by using a heat sink attached to a surface of the CPU. This allows the CPU and other high-performance electronic components in the enclosure to operate within their normal operating temperature ranges, thereby assuring the quality of data management, storage and transfer for the CPU. Oftentimes, fastening devices are required for mounting the heat sink to the CPU.
For example, U.S. Pat. No. 5,384,940 discloses a plurality of conventional fastening devices for mounting a heat sink to an electronic component. The heat sink has a flat base which defines a plurality of holes for receiving the fastening devices therethrough, and a plurality of fins projecting upwardly from a top face of the flat base. Each fastening device comprises a cylindrical head, a shaft body extending downwardly from the head and a cone-shaped locking end. A spring is disposed around the shaft body. The fastening device is preferably formed with a narrow slot longitudinally extending from the locking end into a lower portion of the shaft body thereby providing resiliency to the locking end in a radial direction thereof. In assembly, each fastening device is inserted into the corresponding hole in the flat base of the heat sink and the locking end engages with a corresponding hole defined in a printed circuit board (PCB) thereby securing the heat sink to the electronic component mounted on the PCB.
The fastening devices and the heat sink are generally required to be pre-assembled together before the heat sink is finally mounted to the electronic component in order to facilitate mounting of the heat sink by end users. However, the spring of the conventional fastening device is not elastically deformed to advantageously maintain the fastening device to stand in a vertical direction relative to the heat sink. The end users are required to manually manipulate the fastening device to align the locking end thereof properly with the corresponding hole of the PCB when the heat sink is finally being mounted to the electronic component by the end users, which increases operating complexity and difficulty for the end users.
Therefore, an improved fastening device for mounting a heat sink to a heat generating electronic component which can overcome the above problem is desired.

Fastening device and heat sink assembly using the same


Disclosed is a battery separator consisting essentially of a nonwoven fabric having a substantially unilayered structure, wherein an apparent total surface area of fibers per a surface density of the nonwoven fabric is 20 m2 or more, a thickness of the nonwoven fabric is 0.1 mm or less, a uniformity index of the nonwoven fabric is 0.15 or less, and the nonwoven fabric contains fine fibers having a fiber diameter of 4 μm or less.

1. Field of the Invention
The present invention relates to a battery separator.
2. Description of the Related Art
In a battery, a separator is used to separate a positive electrode and a negative electrode from each other to prevent a short circuit therebetween, and further, to hold an electrolyte thereon and enable a smoothelectromotive reaction.
Recently, in electronic equipment, a space allotted for the battery has become smaller due to the need for miniaturization and weight-saving. Nevertheless, the performance requirement for such a smaller battery is the same as or higher than that for a conventional battery, and therefore, it is necessary to enhance the capacity of the battery, and to increase the amounts of active materials in the electrodes. Accordingly, a volume allotted in the battery for the separator must be reduced. Although a thin separator having a thickness of 0.15 mm was proposed, a thinner separator having a thickness of 0.1 mm or less is desired in the market.
A separator that can be thinned to a thickness of 0.1 mm or less is proposed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 11-126595. This Publication discloses an alkaline battery separator having a mass per unit area of 15 to 55 g/m2, a void rate of 40 to 80%, and a thickness of 0.05 to 0.12 mm, and composed of a laminated nonwoven fabric prepared by adhering fine-fiber nonwoven fabrics onto both sides of a nonwoven fabric produced by a wet-laid method and containing sheath-core type composite fibers consisting of a sheath polymer with a low melting point and a core polymer with a high melting point.
However, the separator disclosed in the above Japanese Unexamined Patent Publication (Kokai) No. 11-126595 is composed of the laminated nonwoven fabric prepared by adhering fine-fiber nonwoven fabrics and the nonwoven fabric produced by a wet-laid method, and thus, the electrolyte is unevenly distributed at the fine-fiber nonwoven fabrics. Therefore, an inner pressure is increased, and as a result, it becomes difficult to enhance the capacity of the battery, although the separator is designed to be thinner to enable an enhancement of the capacity of the battery.


A process of preparing an alkylene glycol which process involves: i) reacting a respective alkylene oxide and water in a first reactor, ii) removing from the first reactor a reactor output mixture comprising an alkylene glycol and unreacted water, iii) transferring a proportion of the reactor output mixture to a distillation unit and a proportion of the reaction output mixture to a second reactor containing a catalyst, iv) reacting the reaction output mixture in the second reactor with a further amount of the respective alkylene oxide, and v) transferring a reactor output mixture from the second reactor to a distillation unit.

Alkylene glycols, in particular monoalkylene glycols, are of established commercial interest. For example, monoalkylene glycols are being used in anti-freeze compositions, as solvents and as base materials in the production of polyalkylene terephthalates e.g. for fibers and bottles.
The production of alkylene glycols by liquid phase hydrolysis of alkylene oxides is known. In commercial production the hydrolysis is performed without a catalyst by adding a large excess of water, e.g. 15 to 30 moles of water per mole of alkylene oxide. The reaction is considered to be a nucleophilic substitution reaction, whereby opening of the alkylene oxide ring occurs, water acting as the nucleophile. Because the primarily formed monoalkylene glycol also acts as a nucleophile, as a rule a mixture of monoalkylene glycol, dialkylene glycol and higher alkylene glycols is formed. In order to increase the selectivity to monoalkylene glycol, it is necessary to suppress the secondary reaction between the primary product and the alkylene oxide, which competes with the hydrolysis of the alkylene oxide.
One effective means for suppressing the secondary reaction is to increase the relative amount of water present in the reaction mixture. Although this measure improves the selectivity towards the production of the monoalkylene glycol, it creates a problem in that large amounts of water have to be removed for recovering the product. Removing this additional water increases production costs as it is energy intensive and requires large-scale distillation facilities.
The demand for monoalkylene glycols has risen significantly in recent years and further growth is expected on account of the increasing popularity of monoalkylene glycol derived products. Most existing commercial alkylene glycol production facilities already operate at or close to maximum (design) capacity. Therefore, to meet the increased demand more efficient methods of producing monoalkylene glycols are required.
In commercial thermal alkylene glycols production processes, the limiting factor on the amount of monoalkylene glycol production is frequently the distillation of water from the aqueous glycol reactor product, as removing the large amounts of water required for high selectivity is a relatively lengthy process. This is problematic as the distillation step acts as a bottleneck, restricting the overall amount of production.
One method of overcoming this problem would be to reduce the ratio of water to alkylene oxide employed in the process. However, this would also increase the relative yield of less desirable higher alkylene glycol products, and possibly necessitate an expansion of facilities to remove and purify the higher alkylene glycol products from the monoalkylene glycol product.
Due to the size and cost of distillation and purification apparatus required to remove water and/or higher glycols, increasing distillation capacity is in many cases neither a practical nor cost-effective solution. Accordingly, it would be advantageous if there was a flexible means with which to overcome this problem such that glycol production could be increased while retaining high selectivity to monoalkylene glycol products.
Catalytic processes for converting alkylene oxides to alkylene glycols have been investigated and catalysts capable of promoting a higher selectivity to monoalkylene glycol product at reduced water levels are known, (e.g. EP-A 015649, EP-A 0160330, WO 95/20559 and U.S. Pat. No. 6,124,508). For some catalysts, such as the quaternary phosphonium cation-containing catalysts of U.S. Pat. No. 6,124,508, it is mentioned that in order to save the catalyst it may be advantageous to subject the alkylene oxide feed stream to partial thermal hydrolysis before completing the hydrolysis catalytically.


Tools and techniques for applying scan patterns during encoding and decoding of interlaced video are described. For example, a video decoder scans transform coefficients from a one-dimensional array to a two-dimensional block according to a scan pattern. The block is 4×4, and the scan pattern biases the vertical direction by starting with the DC coefficient and three AC coefficients of the lowest horizontal frequency. Or, the block is 8×4, and the scan pattern biases the vertical direction by starting with the DC coefficient and three AC coefficients of the lowest horizontal frequency. Or, the block is 4×8, and the scan pattern biases the horizontal direction for the lowest frequency AC coefficients in the horizontal and vertical directions but biases the vertical direction for at least some other AC coefficients. A corresponding video encoder applies the scan patterns to scan transform coefficients from two-dimensional blocks to one-dimensional arrays.

Digital video consumes large amounts of storage and transmission capacity. A typical raw digital video sequence includes 15 or 30 frames per second. Each frame can include tens or hundreds of thousands of pixels (also called pels), where each pixel represents a tiny element of the picture. In raw form, a computer commonly represents a pixel as a set of three samples totaling 24 bits. For instance, a pixel may include an eight-bit luminance sample (also called a luma sample, as the terms "luminance" and "luma" are used interchangeably herein) that defines the grayscale component of the pixel and two eight-bit chrominance samples (also called chroma samples, as the terms "chrominance" and "chroma" are used interchangeably herein) that define the color component of the pixel. Thus, the number of bits per second, or bit rate, of a typical raw digital video sequence may be 5 million bits per second or more.
Many computers and computer networks lack the resources to process raw digital video. For this reason, engineers use compression (also called coding or encoding) to reduce the bit rate of digital video. Compression decreases the cost of storing and transmitting video by converting the video into a lower bit rate form. Decompression (also called decoding) reconstructs a version of the original video from the compressed form. A "codec" is an encoder/decoder system. Compression can be lossless, in which the quality of the video does not suffer, but decreases in bit rate are limited by the inherent amount of variability (sometimes called entropy) of the video data. Or, compression can be lossy, in which the quality of the video suffers, but achievable decreases in bit rate are more dramatic. Lossy compression is often used in conjunction with lossless compression—the lossy compression establishes an approximation of information, and the lossless compression is applied to represent the approximation.
In general, video compression techniques include "intra-picture" compression and "inter-picture" compression, where a picture is, for example, a progressively scanned video frame, an interlaced video frame (having alternating lines for video fields), or an interlaced video field. Intra-picture compression techniques compress individual pictures (typically called I-pictures or key pictures), and inter-picture compression techniques compress pictures (typically called predicted pictures, P-pictures, or B-pictures) with reference to a preceding and/or following picture (typically called a reference or anchor picture) or pictures (for B-pictures).
I. Interlaced Video and Progressive Video
A video frame contains lines of spatial information of a video signal. For progressive video, these lines contain samples starting from one time instant and continuing in raster scan fashion (left to right, top to bottom) through successive, non-alternating lines to the bottom of the frame.
The primary aspect of interlaced video is that the raster scan of an entire video frame is performed in two passes by scanning alternate lines in each pass. For example, the first scan is made up of the even lines of the frame and the second scan is made up of the odd lines of the scan. This results in each frame containing two fields representing two different time epochs. FIG. 1 shows an interlaced video frame (100) that includes top field (110) and bottom field (120). In the frame (100), the even-numbered lines (top field) are scanned starting at one time (e.g., time t), and the odd-numbered lines (bottom field) are scanned starting at a different (typically later) time (e.g., time t+1). This timing can create jagged tooth-like features in regions of an interlaced video frame where motion is present when the two fields are scanned starting at different times. For this reason, interlaced video frames can be rearranged according to a field structure for coding, with the odd lines grouped together in one field, and the even lines grouped together in another field. This arrangement, known as field coding, is useful in high-motion pictures for reduction of such jagged edge artifacts. On the other hand, in stationary regions, image detail in the interlaced video frame may be more efficiently preserved without such a rearrangement. Accordingly, frame coding is often used in stationary or low-motion interlaced video frames, in which the original alternating field line arrangement is preserved.
II. Windows Media Video, Versions 8 and 9
Microsoft Corporation's Windows Media Video, Versions 8 ["WMV8"] and 9 ["WMV9"] each include a video encoder and a video decoder. The encoders use intra-frame and inter-frame compression, and the decoders use intra-frame and inter-frame decompression.
A. Intra-frame Compression and Decompression
FIG. 2 illustrates block-based intra compression in the encoder, which reduces bit rate by removing spatial redundancy in a picture. In particular, FIG. 2 illustrates compression of an 8×8 block (205) of samples of an intra frame by the encoder. The encoder splits the frame into 8×8 blocks of samples and applies an 8×8 frequency transform (210) (such as a discrete cosine transform ["DCT"]) to individual blocks such as the block (205). The encoder quantizes (220) the transform coefficients (215), resulting in an 8×8 block of quantized transform coefficients (225).
Further encoding varies depending on whether a coefficient is a DC coefficient (the top left coefficient), an AC coefficient in the top row or left column, or another AC coefficient. The encoder typically encodes the DC coefficient (226) as a differential from the DC coefficient (236) of a neighboring 8×8 block, which is a previously encoded and decoded/reconstructed top or left neighbor block. The encoder entropy encodes (240) the differential.
The entropy encoder can encode the left column or top row of AC coefficients as differentials from AC coefficients a corresponding left column or top row of a neighboring 8×8 block. FIG. 2 shows the left column (227) of AC coefficients encoded as differentials (247) from the left column (237) of the neighboring (actually situated to the left) block (235).
The encoder scans (250) the 8×8 block (245) of predicted, quantized AC coefficients into a one-dimensional array (255). For the scanning, the encoder uses a scan pattern that depends on the DC/AC prediction direction, as described below. The encoder then entropy encodes the scanned coefficients using a variation of run/level coding (260). The encoder selects variable length codes ["VLCs"] from run/level/last tables (265) and outputs the VLCs.
FIG. 3 shows an example of corresponding decoding (300) for an intra-coded block by the decoder. In particular, FIG. 3 illustrates decompression of an 8×8 block of samples of an intra frame by the decoder to produce a reconstructed version (305) of the original 8×8 block (205).
The decoder receives and decodes (370) VLCs with run/level/last tables (365). The decoder run/level decodes (360) AC coefficients and puts the results into a one-dimensional array (355), from which the AC coefficients are inverse scanned (350) into a two-dimensional block (345). (The scan patterns are described below.)
The AC coefficients of the left column or top row of the block (345) may be differentials, in which case the decoder combines them with corresponding AC coefficients from a neighboring 8×8 block. In FIG. 3, the left column (347) of AC coefficients are differentials, and they are combined with AC coefficients of the left column (337) of a neighboring (actually situated to the left) block (335) to produce a left column (327) of AC coefficients in a block (325) of quantized transform coefficients.
To decode the DC coefficient (326), the decoder decodes (340) a DC differential. The decoder combines the DC differential with a DC coefficient (336) of a neighboring 8×8 block to produce the DC coefficient (326) of the block (325) of quantized transform coefficients.
The decoder inverse quantizes (320) the quantized transform coefficients of the block (325), resulting in a block (315) of transform coefficients. The decoder applies an inverse frequency transform (310) to the block (315) of transform coefficients, producing the reconstructed version (305) of the original 8×8 block (205).
B. Inter-frame Compression and Decompression
FIG. 4 illustrates block-based inter compression in an encoder, and FIG. 5 illustrates corresponding decompression in a decoder. Inter-frame compression techniques often use motion estimation and motion compensation, which reduces bit rate by removing temporal redundancy in a video sequence. Residual information after motion compensation is further compressed by removing spatial redundancy in it.
For example, for motion estimation an encoder divides a current predicted frame into 8×8 or 16×16 pixel units. For a unit of the current frame, a similar unit in a reference frame is found for use as a predictor. A motion vector indicates the location of the predictor in the reference frame. The encoder computes the sample-by-sample difference between the current unit and the predictor to determine a residual (also called error signal). If the current unit size is 16×16, the residual is divided into four 8×8 blocks. To each 8×8 residual, the encoder applies a reversible frequency transform operation, which generates a set of frequency domain (i.e., spectral) coefficients. The resulting blocks of transform coefficients are quantized and entropy encoded. If the predicted frame is used as a reference for subsequent motion compensation, the encoder reconstructs the predicted frame. When reconstructing residuals, the encoder reconstructs transform coefficients (e.g., DCT coefficients) that were quantized and performs an inverse frequency transform such as an inverse DCT ["IDCT"]. The encoder performs motion compensation to compute the predictors, and combines the predictors with the residuals. During decoding, a decoder typically entropy decodes information and performs analogous operations to reconstruct residuals, perform motion compensation, and combine the predictors with the residuals.
When processing 8×8 blocks of motion compensation prediction residuals, the WMV8 encoder/decoder may switch between different sizes of DCT/IDCT. In particular, the WMV8 encoder/decoder may use of one of an 8×8 DCT/IDCT, two 4×8 DCT/IDCTs, or two 8×4 DCT/IDCTs for an 8×8 prediction residual block. The WMV9 encoder/decoder may also use four 4×4 block size transforms for an 8×8 prediction residual block, but uses a transform other than DCT. FIG. 6 illustrates different transform block sizes for an 8×8 prediction residual block. Variable-size transform blocks allows the encoder to choose the block partition that leads to the lowest bit rate representation for a block.
In particular, FIG. 4 shows transform coding and compression of an 8×8 prediction error block (410) using two 8×4 DCTs (440). A video encoder computes (408) an error block (410) as the difference between a predicted block (402) and a current 8×8 block (404). The video encoder applies either an 8×8 DCT (not shown), two 8×4 DCTs (440), or two 4×8 DCTs (not shown) to the error block (410). For the 8×4 DCT (440), the error block (410) becomes two 8×4 blocks of DCT coefficients (442, 444), one for the top half of the error block (410) and one for the bottom half. The encoder quantizes (446) the data, which typically results in many of the coefficients being remapped to zero. The encoder scans (450) the blocks of quantized coefficients (447, 448) into one-dimensional arrays (452, 454) with 32 elements each, such that coefficients are generally ordered from lowest frequency to highest frequency in each array. In the scanning, the encoder uses a scan pattern for the 8×4 DCT, as described below. (For other size transforms, the encoder uses different scan patterns, as described below.) The encoder entropy codes the data in the one-dimensional arrays (452, 454) using a combination of run length coding (480) and variable length encoding (490) with one or more run/level/last tables (485).
FIG. 5 shows decompression and inverse transform coding of an 8×8 prediction error block (510) using two 8×4 IDCTs (540). The decoder may also perform inverse transform coding using a 4×8 IDCT or 8×8 IDCT (not shown). The decoder entropy decodes data into one-dimensional arrays (552, 554) of quantized coefficients using a combination of variable length decoding (590) and run length decoding (580) with one or more run/level/last tables (585). The decoder scans (550) the data into blocks of quantized DCT coefficients (547, 548) using the scan pattern for the 8×4 DCT. (The decoder uses other scan patterns for an 8×8 or 4×8 DCT.) The decoder inverse quantizes (546) the data and applies (540) an 8×4 IDCT to the coefficients, resulting in an 8×4 block (512) for the top half of the error block (510) and an 8×4 block (514) for the bottom half of the error block (510). The decoder combines the error block (510) with a predicted block (502) (from motion compensation) to form a reconstructed 8×8 block (504).
C. Scan Patterns in WMV8 and WMV9
During encoding, it is common for most of the transform coefficients of a transform block to have a value of zero after quantization. A good scan pattern gives higher priority to coefficients that are more likely to have non-zero values. In other words, such coefficients are scanned earlier in the scan pattern. In this way, the non-zero coefficients are more likely to be bunched together, followed by one or more long groups of zero value coefficients. In particular, this leads to more efficient run/level/last coding, but other forms of entropy coding also benefit from the reordering.
A WMV8 encoder and decoder use different scan patterns for different size transform blocks. FIGS. 7A through 7F show scan patterns for different block sizes and intra or inter compression types according to WMV8. In general, the same scan patterns are used for progressive frames and interlaced frames.
FIGS. 7A through 7C show scan patterns for intra-coded blocks of I-pictures. In general, one of the three scan arrays is used for a given intra-coded block depending on the AC prediction status for the block. If AC prediction is from the top, the horizontal scan pattern shown in FIG. 7B is used. If AC prediction is from the left, the vertical scan pattern shown in FIG. 7C is used. And if no AC prediction is used, the normal scan pattern shown in FIG. 7A is used.
FIGS. 7D through 7F show scan patterns for blocks of P-pictures. FIG. 7D shows a scan pattern for an intra-coded block or 8×8 inter-coded block in a P-picture. FIGS. 7E and 7F show scan patterns for inter-coded 8×4 and 4×8 blocks, respectively, in a P-picture.
A WMV9 encoder and decoder also use the scan patterns shown in FIGS. 7A through 7F. FIG. 7G shows a scan pattern for 4×4 inter-coded block size, which is another block size option according to WMV9. Again, the same scan patterns are used for progressive frames and interlaced frames (with the exception of scanning chrominance transform coefficients, which are in 4×8 blocks due to the chrominance sampling pattern in WMV9).
While the scan patterns in WMV8 and WMV9 help overall performance in many scenarios, there are opportunities for improvement. In particular, the 8×4 and 4×8 inter scan patterns are not particularly well suited for many common configurations of non-zero transform coefficients for progressive video in 8×4 and 4×8 inter-coded blocks. As a result, the scan patterns often provide sub-optimal re-ordering of transform coefficients for progressive video in 8×4 and 4×8 inter-coded blocks, which hurts the efficiency of subsequent entropy coding. Since the scan pattern affects block-level operations, and since each video picture can include hundreds or thousands of blocks, even a small change in efficiency can dramatically affect overall compression results.
Similarly, the scan patterns are not particularly well suited for common configurations of non-zero transform coefficients in inter-coded blocks of interlaced video. Again, this hurts the efficiency of subsequent entropy coding and can dramatically affect overall compression results.
III. Video Codec Standards
Various standards specify aspects of video decoders as well as formats for compressed video information. These standards include H.261, MPEG-1, H.262 (also called MPEG-2), H.263, and MPEG-4. Directly or by implication, these standards may specify certain encoder details, but other encoder details are not specified. Different standards incorporate different techniques, but each standard typically specifies one or more scan patterns for transform coefficients as briefly discussed below. For additional detail, see the respective standards.
A. Scan Patterns in the H.261 and MPEG Standard
The H.261 standard describes a transmission order for transform coefficients in an 8×8 block (compressed using intra-compression or motion compensation). The transform coefficients are run/level coded in the transmission order shown in FIG. 8. The transmission order proceeds from the low frequency coefficient at the upper left of the block in a neutral, zigzag pattern down to the highest frequency coefficient at the bottom right of the block.
The scan pattern described in the MPEG standard is basically the same as the scan pattern shown in FIG. 8. AC coefficients of intra-coded blocks are processed according to the scan pattern. The DC coefficient and AC coefficients of inter-coded blocks are processed according to the scan pattern.
The scan pattern shown in FIG. 8 is neutral in that neither rows nor columns are favored over the other in the ordering. The effectiveness of the scan pattern is limited in that it does not work for block sizes other than 8×8 and is not well suited for interlaced video.
B. Scan Patterns in the H.262 Standard
The H.262 standard describes two different 8×8 scan patterns. The syntax element "alternate_scan" (signaled at picture layer in the bitstream) indicates which of the two scan patterns to use for a picture.
The first H.262 scan pattern is the scan pattern described in the MPEG-1 standard, which is a neutral, zigzag scan pattern. FIG. 9 shows the other H.262 scan pattern. The scan pattern shown in FIG. 9 is biased in the vertical direction in that columns are favored over rows in the ordering. For example, columns are scanned earlier in the order such that the first column finishes before the first row, the second column finishes before the second row, etc. The scan patterns still do not work for block sizes other than 8×8, however. Moreover, the use of an additional bit per picture just for this purpose adds to bit rate and encoder/decoder complexity.
C. Scan Patterns in the H.263 and MPEG-4 Standards
The H.263 standard describes three different 8×8 scan patterns. The type of prediction used for DC and AC coefficients for a block indicates which scan pattern to use. If no AC prediction is used for an intra-coded block, and for all non-intra-coded blocks, the neutral, zigzag scan pattern shown in FIG. 8 is chosen. If the vertically adjacent block is used to predict the DC coefficient and top row of AC coefficient of the current intra-coded block, the scanning pattern shown in FIG. 10 (H.263 alternate horizontal scan) is chosen to scan the stronger, horizontal frequencies prior to the vertical ones. On the other hand, if the horizontally adjacent block is used to predict the DC coefficient and left column of AC coefficient of the current intra-coded block, a scanning pattern like the one shown in FIG. 9 is chosen to scan the stronger, vertical frequencies prior to the horizontal ones. (The H.263 alternate vertical scan has the same pattern as the alternate scan in H.262, with the numbers are increased by 1 throughout.)
Similarly, the MPEG-4 standard describes a neutral scan pattern, an alternate horizontal scan pattern, and an alternate vertical scan pattern, where the scan pattern used depends on whether or not the block is intra-coded and the prediction direction.
As with various previous standards, the H.263 and MPEG-4 scan patterns do not work for block sizes other than 8×8.
D. Scan Patterns in the Drafts of the H.264 Standard
Draft JVT-D157 of the H.264 standard describes two sets of four scan patterns—a first set of four neutral, zigzag scan patterns and a second set of four field scan patterns. By default, the 4×4 scan pattern shown in FIG. 11A is used for 4×4 partitions of blocks. The 4×4 scan pattern is a neutral, zigzag pattern that biases neither the horizontal nor vertical direction.
If adaptive block size transforms are used, however, additional scan patterns are used for different block sizes. With adaptive block size transforms, transform block sizes of 4×8, 8×4, and 8×8 (in addition to 4×4) are available for luminance motion compensation residual information. Draft JVT-D157 describes decoding of either progressive frames or interlaced frames, which may be mixed together in the same video sequence. For blocks encoded/decoded in frame mode (e.g., for progressive frames), the zigzag scan patterns shown in FIGS. 8 and 11A through 11C are used for the respective block sizes. For blocks encoded/decoded in field mode (e.g., for interlaced fields), the field scan patterns shown in FIGS. 11D through 11G are used for the respective block sizes.
While the scan patterns in JVT-D157 provide good performance in many scenarios, there are opportunities for improvement. In particular, the 8×4 and 4×8 zigzag scan patterns are not particularly well suited for many common configurations of non-zero transform coefficients for progressive video in 8×4 and 4×8 inter-coded blocks, which hurts the efficiency of subsequent entropy coding. Moreover, the 8×8, 8×4, and 4×4 field scan patterns, while somewhat vertically biased, are not biased aggressively enough in the vertical direction to be effective for inter-coded blocks of interlaced video fields. The 4×8 field scan pattern is vertically biased, but fails to account for common configurations of non-zero transform coefficients in 4×8 inter-coded blocks of interlaced video fields. Each of these things hurts the efficiency of subsequent entropy coding and adversely affects overall compression results.
Given the critical importance of video compression and decompression to digital video, it is not surprising that video compression and decompression are richly developed fields. Whatever the benefits of previous video compression and decompression techniques, however, they do not have the advantages of the following techniques and tools.

This patent is subject to a terminal disclaimer.

Scan patterns for interlaced video content


A sheet tray assembly including: (a) a tray unit configured to accommodate sheets, and having an upper opening for allowing the sheets to be introduced into the tray unit via the upper opening; (b) a cover unit configured to cover the upper opening; and (c) a link interconnecting the tray unit and the cover unit, and having (c-1) a first end portion at which the link is connected to the tray unit and (c-2) a second end portion at which the link is connected to a proximal end portion of the cover unit. The link is movable between first and second pivot positions as a result of pivot movement of the link relative to the tray unit, whereby a posture of the link is changeable by the pivot movement, such that the second end portion of the link is placed in a first height level when the link is positioned in the first pivot position, and is placed in a second height level that is higher than the first height level when the link is positioned in the second pivot position.

1. Field of the Invention
The present invention relates to a sheet tray assembly that is to be detachably disposed in an image recording apparatus.
2. Discussion of Related Art
In an inkjet printer, recording sheets are conveyed along a sheet path by a sheet conveyor, and each of the recording sheets is subjected to a recording operation performed by an image recorder. The recording sheet is performed by a recording head of the image recorder which is activated to eject ink onto each recording sheet while the recording sheet is being conveyed. US 2007/0138193A1 (corresponding to JP-2007-160816A) discloses an inkjet printer in which a printer cover can be opened to permit a maintenance operation to be performed onto a sheet conveyor and an image recorder that are provided inside the printer. The printer cover is connected via a link to a housing of a main body of the printer. The link has holes provided in its respective opposite end portions. A first shaft provided in the housing is introduced in one of the holes of the link, while a second shaft provided in the printer cover is introduced in the other of the holes of the link. A coil spring is attached to the first shaft, and constantly forces or biases the link to be pivoted in a direction that causes the pivot cover to be opened. The printer cover is pivotable relative to the housing about the first and second shafts, i.e., two axes. When the printer cover is raised by a user, the printer cover and the link are pivoted integrally with each other relative to the main body of the printer. When the link has been pivoted to a predetermined position, the link is brought into contact at its protruding portion with the housing. In this state, the pivot movement of the link is stopped by the contact of the link with the housing. From this state, the printer cover is pivoted relative to the link as well as the main body of the printer. An opening of the main body of the printer is thus exposed.
Some of image recording apparatuses such as inkjet printers and laser printers are equipped with sheet tray assemblies such as sheet-supplying cassettes. The sheet tray assembly is provided for accommodating recording sheets each of which is to be subjected to an image recording operation, and is detachably disposed in the image recording apparatus. The sheet tray assembly has a tray unit and a cover unit. The tray unit has an upper opening for allowing the recording sheets to be introduced into the tray unit via the upper opening. The cover unit is disposed on an upper side of the tray unit to cover a rear side region of the upper opening of the tray unit, and is pivotable relative to the tray unit about a pivot axis. A front side region of the upper opening of the tray unit is uncovered, because a pickup roller is disposed in the front side region of the upper opening so as to be held in pressing contact with the recording sheets accommodated in the tray unit. The pivot axis is located in the upper opening of the tray unit. When the cover unit is opened, the rear side region of the upper opening of the tray unit is uncovered, and the recording sheets can be accommodated in the tray unit by introducing leading ends of the respective recording sheets into the tray unit via a space defined on a lower side of the pivot axis.
In the above-described conventional sheet tray assembly, since the pivot axis (about which the cover unit is pivotable) is located in the upper opening of the tray unit, a proximal end portion of the cover unit which is in the vicinity of the pivot axis enters into the tray unit when the cover unit is opened. Therefore, the above-described space defined on the lower side of the pivot axis is reduced when the cover unit is opened, thereby causing a problem that only a limited number of sheets (e.g., recording sheets) can be introduced into the tray unit via the recued space, namely, only a limited number of sheets can be accommodated in the tray unit. In other words, there is a problem that the entrance of the proximal end portion of the cover unit into the tray unit causes a dead space within the tray unit wherein the dead space is not available for accommodation of the sheets. It might be possible to solve the problem, for example, by heightening a position of the pivot axis. However, heightening the position of the pivot axis causes another problem that the image recording apparatus as a whole is increased in size. Anyway, it has been difficult to utilize an entirety of inner space of the sheet tray assembly as a space available for accommodating therein the sheets.


A method for producing a lead frame having outer leads and inner leads, for use in constructing a resin-sealed semiconductor package comprises etching processes for etching a blank. A first resist pattern having a first opening and a second resist pattern having second openings are formed on the first and the second major surfaces of a blank. The first and the second major surfaces of the blank are etched through the first and the second resist pattern by a first etching process using a first etchant to form a first recess corresponding to the first opening and second recesses corresponding to the second recesses in the first and the second major surfaces, respectively. The first recess is filled up with an etch-resistant layer. The second major surface is etched through the second resist pattern by a second etching process using a second etchant so that portions of the blank corresponding to the second openings of the second resist pattern are etched through to form the tips of the inner leads.

The present invention relates to a lead frame and a method for producing a lead frame. More particularly, the present invention relates to a lead frame capable of being produced by an etching process and a method for producing such a lead frame.
Referring to FIG. 8 showing the configuration of a generally known resin-sealed semiconductor package 60, such as a plastic lead frame package, when fabricating the resin-sealed semiconductor package 60, a semiconductor device 69 is mounted on a lead frame 61 of 42 Alloy (a Ni/Fe alloy comprising 42% Ni)alloy), and then the semiconductor device 69 is sealed with a resin 65. The number of the inner leads 63 of the lead frame 61 is equal to that of the bonding pads 66 of the semiconductor device 69. The lead frame 61 has a die pad 62 to be mounted with the semiconductor device 69, and outer leads 64 to be electrically connected to the associated circuits. The tips of the inner leads 63 are connected electrically to the bonding pads 66 of the semiconductor device 69 with bonding wires 67, respectively. After mounting the semiconductor device 69 on the die pad 62 and connecting the bonding pads 66 to the inner leads 63, respectively, the semiconductor device 69 is sealed with the resin 65 to protect the semiconductor device 69 from external stresses and contaminants.
Recently, there has been growing demand for the miniaturization and reduction in thickness of resin-sealed semiconductor packages employing lead frames like the lead frame 61 (plastic lead frame packages) and the increase of the number of terminals of resin-sealed semiconductor packages as electronic apparatuses are miniaturized progressively and the degree of integration of semiconductor devices increases progressively. Consequently, recent resin-sealed semiconductor packages, particularly, quad flat packages (QFPs) and thin quad flat packages (TQFPS) have each a greatly increased number of pins.
Lead frames having fine inner leads arranged at small pitches among lead frames for semiconductor packages are fabricated by a photolithographic etching process, while lead frames having inner leads arranged at comparatively large pitches among lead frames for semiconductor packages are fabricated by press working. However, lead frames having a large number of fine inner leads to be used for forming semiconductor packages having a large number of pins are fabricated by subjecting a blank of a thickness on the order of 0.25 mm to an etching process regardless of size.
The etching process for forming a lead frame having fine inner leads will be described hereinafter with reference to FIG. 7. First a copper alloy or 42 alloy thin sheet 51 of a thickness on the order of 0.25 mm (blank for a lead frame) is cleaned perfectly (FIG. 7(a)). Then, a photoresist, such as a water-soluble casein photoresist containing potassium dichromate as sensitive agent, is spread in photoresist films 52 over the opposite major surfaces of the thin sheet 51 as shown in FIG. 7(b). Then, the photoresist films 52 are exposed through a mask of a predetermined pattern to light emitted by a high-pressure mercury lamp, the thin sheet 51 is immersed in a developer for development to form a patterned photoresist films 53 as shown in FIG. 7(c). Then, the thin sheet 51 is subjected, when need be, to a hardening process, a washing process and such, and then an etchant containing ferric chloride as a principal component is sprayed against the thin sheet 51 to etch through portions of the thin sheet 51 not coated with the patterned photoresist films 53 so that inner leads 63 of predetermined sizes and predetermined shapes are formed as shown in FIG. 7(d). Then, the patterned resist films 53 are removed, the patterned thin sheet 51 is washed to complete a lead frame 61 having the inner leads 63 of desired shapes as shown in FIG. 7(e).
Predetermined areas of the lead frame 61 thus formed by the etching process are silver-plated. After being washed and dried, an adhesive polyimide tape is stuck to the inner leads 63 for fixation, predetermined tab bars are bent, when need be, and the die pad is depressed.
In the etching process, the etchant etches the thin sheet 51 in both the direction of the thickness and directions perpendicular to the direction of the thickness, which limits the miniaturization of inner lead pitches of lead frames.
Since the thin sheet 51 is etched from both the major surfaces as best shown in FIG. 7(d) during the etching process, it is said, when the lead frame has a line-and-space shape, that the smallest possible intervals between the lines are in the range of 50 to 100% of the thickness of the thin sheet 51.
From the viewpoint of forming the outer leads 64 having a sufficient strength, generally, the thickness of the thin sheet 51 must be about 0.125 mm or above.
Furthermore, the width of the inner leads 63 must be in the range of 70 to 80 .mu.m for successful wire bonding. When the etching process as illustrated in FIG. 7 is employed in fabricating a lead frame, a thin sheet of a small thickness in the range of 0.125 to 0.15 mm is used and inner leads are formed by etching so that the fine tips thereof are arranged at a pitch of about 0.165 mm.
However, recent miniature resin-sealed semiconductor packages requires inner leads arranged at pitches in the range of 0.13 to 0.15 mm, far smaller than 0.165 mm. When a lead frame is fabricated by processing a thin sheet of a reduced thickness, the strength of the outer leads of such a lead frame is not large enough to withstand external forces that may be applied thereto in the following processes including an assembling process and a chip mounting process. Accordingly, there is a limit to the reduction of the thickness of the thin sheet to enable the fabrication of a minute lead frame having fine leads arranged at very small pitches by etching.
An etching method previously proposed to overcome such difficulties subjects a thin sheet to an etching process to form a lead frame after reducing the thickness of portions of the thin sheet corresponding to the inner leads of the lead frame by half etching or pressing to form the fine inner leads by etching without reducing the strength of the outer leads. However, problems arise in accuracy in the following processes when the lead frame is formed by etching after reducing the thickness of the portions corresponding to the inner leads by pressing; for example, the smoothness of the surfaces of plated areas is unsatisfactory, the inner leads cannot be formed in a flatness and a dimensional accuracy required to clamp the lead frame accurately for bonding and molding, and a platemaking process must be repeated twice making the lead fabricating process intricate. It is also necessary to repeat a platemaking process twice when the thickness of the portions of the thin sheet corresponding to the inner leads is reduced by half etching before subjecting the thin sheet to an etching process for forming the lead frame, which also makes the lead frame fabricating process intricate. Thus, this previously proposed etching method has not yet been applied to practical lead frame fabricating processes.
In some cases, oxides and hydroxides are formed on the surfaces of portions of a lead frame and the surfaces of the portions are tarnished due to etching when the lead frame is formed by etching a thin sheet of a copper alloy, i.e., a blank for forming the lead frame, which is inferred to be due to the action of dissolved oxygen and the like contained in a washing liquid (water) used for cleaning the lead frame after etching on the highly reactive metal surfaces exposed by etching. Such an oxide and a hydroxide are hard to dissolve and cannot be completely removed by a chemical polishing process, i.e., a preprocessing process preceding a plating process, to which the lead frame formed by etching is subjected before a plating process.
The tips of the inner leads of the lead frame to be electrically connected to the terminals of a semiconductor device by bonding wires are plated with gold or the like. If the surfaces of areas to be plated of the tips of the inner leads are coated with the oxide or the hydroxide, the oxide or the hydroxide cannot be completely removed by the chemical polishing process, consequently, the areas of the tips of the inner lead cannot be uniformly plated and faulty wire-bonding results.
Accordingly, there has been a demand for a lead frame having fine inner leads arranged at very small pitches suitable for forming a miniaturized semiconductor package having an increased number of pins, having outer leads having a sufficiently high strength, and having less portions tarnished by an oxide or a hydroxide, and for a method of fabricating such a lead frame.

Process for etching a semiconductor lead frame


A device for training/controlling and tracking an animal is described. The device includes both an aversive stimuli unit and a global positioning satellite system unit in a housing. Coupled to the housing is a harness, collar or other mechanism for attaching the device to an animal. The aversive stimuli unit is remotely operable using a hand-held control unit to aversively stimulate the animal wearing the housing. The global positioning satellite unit coupled to the housing allows determination of the animal's position relative to the operator of the hand-held control unit. A preferred embodiment of the present invention is designed particularly for tracking and training or controlling one or more dogs.

Remote dog training devices that include hand-held remote-control radio transmitters and light-weight radio receivers are known. In fact, there are a number of publications that describe training animals using electric shock collars. For example, Understanding Electronic Dog-Training, by Dr. Daniel F. Tortora (1982), describes methods for using shock collars for training animals. Moreover, some of these inventions have been patented. For example, U.S. Pat. No. 4,335,682 describes a remotely controlled device that is worn by a dog. The device produces stimuli, such as an aversive electrical stimulus, that is followed by a sound or other second stimulus to condition the animal. This helps train the animal for its own safety, or perhaps to provide a relaxation response. Other stimuli also may be produced just prior to the onset of the aversive electrical stimulation. This becomes a conditioned warning stimulus to the animal.
U.S. Pat. No. 4,471,954 states that it is essential that training collars reliably and consistently apply an intended degree of stimulus to the animal. This is complicated by the fact that dogs have various coat and skin thicknesses. Also, certain environmental factors may change the conductivity of the animal's coat or skin, and hence the intensity of the signal perceived by the animal wearing the collar. One example of such an environmental factor is humidity or rain. If the animal's fur is wet, its ability to conduct electricity increases. As a result, stimulating the animal at an early stage in a field training exercise may be less intensely received by the animal compared to the intensity of the stimulus received after the dog's coat is moistened.
Another animal training apparatus is described in U.S. Pat. No. 4,802,482. This patent also concerns solving the problem of providing optimum stimulus levels to the dog for particular training conditions. If the stimulus is too intense, it may have negative effects on the animal. On the other hand, the stimulus must be sufficiently intense to achieve the desired training or control desired.
While a number of inventions are known for remotely stimulating dogs and other animals for training purposes, it still is difficult to track such animals if they are off-leash and moving far afield. In fact, dogs often are lost during training exercises or competitions as they wander too far from the owner or trainer. In this situation, not only may a prize animal be lost but so would the expensive training collar being worn by the animal.

Animal training and tracking device having global positioning satellite unit


A vehicle lighting device is provided to maintain a viewability of light even when seen from a diagonal direction having a predetermined angle to an irradiation direction of the lighting device. The vehicle lighting device includes a board, which includes an array of a plurality of light sources. The vehicle lighting device also includes wall portions that bulge in an irradiation direction of the light sources from edge surfaces of the board. The wall portions also form a polygon surrounding the board. At least one of the wall portions includes a reflective surface on a side facing the light sources.

Generally a lighting device may be attached to a vehicle, such as a motorcycle, to emit light to an occupant of another vehicle, a pedestrian, and the like. Therefore, various structures have been studied in order to improve viewability of light and appearance design of the lighting device, and to reduce manufacturing cost thereof.
Patent Document 1 (Japanese Patent Application Publication No. 2000-331509) generally discusses a vehicle lighting device in which the number of light-emitting diodes appears to be greater than the actual number when the lighting device is seen from an irradiation side thereof by arranging multiple reflective surfaces in the circumference of a light source attachment surface to which the light-emitting diodes serving as light sources are attached.
When a viewer, such as an occupant of another vehicle or a pedestrian, sees a lighting device attached to a vehicle, the viewer likely sees the lighting device from directions other than the front even if the irradiation direction of the lighting device is directed to a front side of the vehicle body. For example, when a lighting device attached to the front of the vehicle body of a running vehicle is seen by an occupant of another vehicle running in the opposite lane, an angle of the lighting device with respect to the direction of the eyes of the occupant, who is looking straight ahead, of another vehicle sequentially changes. Specifically, as the distance between the two vehicles decreases, such an angle changes from approximately zero degrees where the two vehicles are sufficiently distant to approximately 90 degrees where the two vehicles pass each other. Meanwhile, when a pedestrian sees the lighting device attached to the front of the vehicle body of a stopped vehicle, the direction of the eyes of the pedestrian looking at the lighting device changes in accordance with a distance between the pedestrian and the vehicle. In this manner, the viewer likely sees the lighting device of the vehicle from a diagonal direction having a predetermined angle from the irradiation direction of the lighting device. Thus, the lighting device of the vehicle preferably has a configuration with which the viewability does not decrease even when seen diagonally.
Although the lighting device described in Patent Document 1 can make the number of light-emitting diodes appear to be greater than the actual number when seen from the front by arranging multiple reflective surfaces, Patent Document 1 does not take into consideration how the light-emitting diodes are seen from a diagonal direction.


An asphalt release agent and a method of applying the same, including a water-based solution of magnesium chloride and/or calcium chloride together with a phosphate ester corrosion inhibitor, an anionic isopropyl alcohol surfactant and a dye. The release agent is applied using a spray gun in combination with an air compressor to add air to foam the release agent.

Most roads are paved with asphalt, which is produced at an asphalt plant and transported to the construction site in large truck beds such as dump trucks. A difficulty with the transportation operation is that the asphalt tends to stick to the metal surface of the truck bed. The sticking of the asphalt to the bed prevents the asphalt from smoothly sliding out of the bed as the dump truck attempts to discharge its asphalt load. In order to overcome this, workers must coax the asphalt out of the bed using tools. This sticking of the asphalt also affects the tools and other equipment such as rollers.
Asphalt release agents are a well known approach to preventing asphalt from sticking to metallic surfaces. A common release agent used in the past was a hydrocarbon fuel such as ordinary diesel fuel. Such fuels are extremely effective in cutting asphalt in order to prevent it from sticking. However, the reason for their effectiveness is that they combine with and dilute the asphalt. This impairs the structural integrity of the laid asphalt in the roadway. Also, the indiscriminate use of fuel as a release agent contaminates the ground beneath the truck where the agent is applied due to the runoff of excess from the truck onto the ground. For these reasons, the Department of Transportation and many state highway departments have severely restricted the use of fuel as a release agent.
There are other asphalt release agents that are not fuel-based. However, most of these other release agents suffer from some combination of being limited in their effectiveness, being environmentally dangerous, or being expensive. Most of these other release agents also suffer from their complexity in either the delivery, preparation or application steps of utilization. In addition, it is desirable that a release agent contain a corrosion inhibitor to prevent or at least inhibit corrosion of the surfaces to which it is applied, and many of the alternate release agents have no such inhibitor.
It is apparent that there is a need for an asphalt release agent which is effective in preventing the sticking of asphalt to truck beds and other surfaces, is environmentally safe, inhibits corrosion of the surfaces to which it is applied, and is inexpensive.


A pulse combustor system for operating pulse combustors in anti-phase. The pulse combustor system includes two pulse combustors connected at their combustion chambers by a connecting tube. Each of the pulse combustors has a fundamental oscillation mode and one or more additional oscillation modes when operated in isolation. The connecting tube has a length corresponding to ¼ of the fundamental oscillation mode wavelength.

A typical pulse combustor (or pulsejet engine) consists of a combustion chamber, an inlet pipe, a fuel injector, a spark plug (or other ignition means), and an exhaust pipe. The combustion chamber, inlet pipe and exhaust pipe are often cylindrical, but are not limited to such geometry and can take on a variety of shapes. The diameter of the inlet and exhaust pipes is generally smaller than the diameter of the combustion chamber, and the length of the inlet pipe is generally significantly smaller than the length of the exhaust pipe.
The advantages of pulse combustors include their ability draw in fresh air and sustain operation without any external machinery or moving parts. Pulse combustors can also be used as thrust-producing devices, in which case they are commonly referred to as "pulsejet" or "pulse jet" engines. Pulsejet engines have been in use for a long time and have been used to propel several types of aircraft over the last century. Pulsejet engines are often characterized by a diverging exhaust pipe to aid in thrust production.
Pulsejet engines are characterized by their simplicity, particularly because of the lack of moving parts. However, the oscillating nature of the flows into and out of the pulsejet engines tends to produce very high noise and vibration levels that have often been cited as the most serious hurdles in the widespread implementation of pulsejet engines. One particular goal in developing improved pulsejet engines is addressing the high noise and vibration levels. Further, another goal in developing improved pulsejet engines is improving efficiency, mechanical energy conversion, and/or thrust from pulsejet engines.
It has previously been proposed that one way to counter the oscillating nature of a pulsejet engine is to operate two pulsejet engines simultaneously but in anti-phase. In this manner, the oscillating nature of one pulsejet engine is countered by the other. An arrangement to produce such operation between two pulsejet engines has been designed and tested by several researchers, for example, in U.S. Pat. No. 4,840,558 A. This arrangement requires the exhaust pipes of two pulsejet engines to be connected via a chamber with relatively large volume and/or requires the inlet pipes of two pulsejet engines to be connected via a chamber with a relatively large volume. These connecting chambers are often referred to as 'decoupling chambers'. While this arrangement has been successful in producing anti-phase operation, it also has the detrimental effect of reducing oscillation pressure amplitude of the engines, as has been noted by several researchers, including, for example, R. G. Evans and A. S. Alshami in their paper Pulse Jet Orchard Heater System Development: Part I. Design, Construction, and Optimization, the disclosure of which is incorporated herein by reference in its entirety. This loss of oscillation pressure amplitude manifests itself as a reduction in useful mechanical power output, or in the case of a thrust-producing pulsejet, as a loss of thrust. The loss of pressure amplitude can occur for several reasons, one of which is that the insertion of a decoupling chamber between the intake pipe and the atmosphere provides higher resistance to flow drawn into the combustion chamber from the atmosphere, as compared to the case with no decoupling chamber. The result is that a smaller amount of air enters the chamber for a given pressure difference between the combustion chamber and the atmosphere, resulting in lower amounts of fuel that can be burned, and subsequently, lower energy release per cycle. Similarly, the insertion of a decoupling chamber between the exhaust pipes of pulsejets impedes the high-velocity exhaust gases, also leading to thrust loss.
None of the prior tools are especially well optimized for operating two pulsejet engines (or pulse combustors) in anti-phase. One goal in developing improved systems and methods for operation of pulsejet engines (or pulse combustors) is to provide an arrangement which would produce anti-phase operation between two pulsejet engines (or pulse combustors) with minimal interference in the operation of the individual pulsejet engines (or pulse combustors).

Systems and methods for anti-phase operation of pulse combustors


N-Substituted indenoisoquinoline compounds, and pharmaceutical formulations of N-substituted indenoisoquinoline compounds are described. Also described are processes for preparing N-substituted indenoisoquinoline compounds. Also described are methods for treating cancer in mammals using the described N-substituted indenoisoquinoline compounds or pharmaceutical formulations thereof.

The control and cure of cancer represents one of our most challenging health problems. The treatment of cancer can be approached by several modes of therapy including surgery, radiation, chemotherapy or a combination of any of these treatments. Chemotherapy continues to be an indispensable therapy for inoperable or metastatic forms of the disease. Thus, the discovery of compounds specifically targeting cancer cells, or the cellular mechanisms involved in the proliferation of cancer cells, can provide significant advancement in the eradication or control of cancer.
The selection of compounds having effective anticancer activity is complicated by the still limited knowledge of cancer cell biology and biochemistry. Therefore, development of new effective anti-cancer agents remains heavily dependent on screening of new compounds for cytotoxic activity. Antineoplastic drug candidates exhibit enhanced cytotoxicity against cancer cells relative to normal cells. Methods of screening for anticancer activity have focused on several targets, (1) the ability of a compound to inhibit tumor growth and/or progression in animal studies; (2) inhibition of cell growth/proliferation in cell lines of cancerous origin; and (3) inhibition of intracellular processes necessary for the growth or propagation of cancer cells.
The mouse L1210 leukemia cell line was initially the preferred model system used for screening compounds for anti-cancer activity. However, the P388 murine leukemia system was found to be more sensitive and predictive than L1210 leukemia system; it has been used as a primary screen during the past decade. Systematic screening for compounds exhibiting toxicity to these two cell lines has resulted in the isolation of a large number of active natural products. However, the anticancer activities of these compounds were predominantly for leukemia, lymphoma and a few rare tumors. Low clinical efficacy, or the lack of clinical efficacy of known chemotherapeutics against slower growing solid tumors, is a serious concern.
Considering the diversity of cancer in terms of cell type, morphology, growth rate and other cellular characteristics, the U.S. National Cancer Institute (NCI) has developed a disease-oriented approach to anticancer activity screening (M. R. Boyd, in "Principle of Practice of Oncology" J. T. Devita, S. Hellman, S. A. Rosenberg (Eds.) Vol. 3, PPO Update, No. 10, 1989). This in vitro prescreening system is based on the measurement of anticancer cytotoxicity against human cancer cell line panels consisting of approximately 60 cell lines of major human cancers (including leukemia, and slower growing tumor cells such as lung, colon, breast, skin, kidney, etc.) and is referred hereinafter as "COMPARE" screening. An important advantage of the new in vitro screening panels is the opportunity to facilitate identification of compounds that are selectively more cytotoxic to cells of certain types of cancers, thus increasing the ability to select compounds for further study with respect to specific diseases.
Anticancer agents are known to act through a variety of mechanisms to destroy or inhibit the proliferation of cancer cells. For example, some agents are antimetabolites which act as false substrates in the biochemical processes of cancer cells. One compound which has this mechanism of action is methotrexate, an analog of folic acid, which functions in part by binding to dihydrofolate reductase, thereby preventing the formation of guanine and adenine from the folic acid precursor molecule. Thus, methotrexate inhibits the ability of cancer cells to construct DNA by inhibiting the proper metabolism of folic acid.
Other anticancer agents act by alkylating DNA strands, thereby producing defects in the normal double helical structure of the DNA molecule. This alkylation may cause the formation of breaks and inappropriate links between (or within) strands of DNA. Such disruption of the DNA structure, if not repaired by intracellular repair mechanisms, impairs the cell's ability to replicate its DNA. Examples of alkylating anticancer agents are cyclophosphamide and chlorambucil.
Some anticancer agents target the intracellular mechanisms involved in replication of the DNA strand itself. Replication of a cell's genetic material requires a means to pull the DNA double helix apart into two strands. This separation is typically accomplished by the enzyme topoisomerase I. Disruption of the function of this enzyme results in DNA strand breaks in cells that are dividing, thereby causing the death of the dividing cell. Because cancer cells grow and reproduce at a much faster rate than normal cells, they are more vulnerable to topoisomerase I inhibition than are normal cells. Thus, agents that inhibit topoisomerase I are known to be potent anticancer agents. The drug camptothecin was shown to be an inhibitor of topoisomerase I and a potent anticancer agent. However, it has been observed that camptothecin may produce toxic side effects. In addition, the effectiveness of camptothecin is hampered by both the instability of the molecule itself, resulting in lactone ring opening, and the reversible nature of the inhibition, allowing impacted cells to recover. Therefore, the search for potent inhibitors of topoisomerase I continues.

N-substituted indenoisoquinolines and syntheses thereof

The United States of America as represented by the Department of Health and Human Services


A method for controlling the transmission of information between electronic components in a motor vehicle, which components can be either data sources or data sinks, in which a cascade design is used to facilitate the transmission of information. By separating the control signal from the actual streams of data, a flexible, chain type of structure is obtained.

The invention proceeds from a method for controlling the transmission of data between electronic components, preferably in a motor vehicle, which either supply information or process it, and which are linearly connected to each other and to a controlling component by a data bus.
Methods for controlling the transmission of data between electronic components in a motor vehicle are already known, i.e., methods which help solve the problem of finding space for motor vehicle components which provide information and entertainment by increasing their functionality and complexity in spite of the high level of their integration. This approach leads to networked systems and decentralized components. It is necessary not only to control and monitor information but also to transmit audio and video data as well as possibly the data stored on a CD-ROM (called "data" or "useful data" in the following). A modular concept, which allows the data to be transmitted over coaxial cables or fiber-optic waveguides, usually made of plastic, is required for the transmission of these data. For cost reasons, standard communications protocols are used for these transmissions.
A networking of components in motor vehicles in the form of a star topology is known. In this design, several data sources are connected to a data sink. The number of these sources cannot be exceeded by the limited number of free inputs. In addition, a large amount of space is required, and the large number of plug contacts which the data sink must have is also disadvantageous.
Optical ring structures are also known, in which both data and control/monitoring information are transmitted over the transmission medium. Each component, whether data source or data sink, has an optoelectronic converter at its input and an electro-optic converter at its output. A protocol processor makes it possible for the data to be read in and out. In a ring structure, the data stream must be clocked. The disadvantage of a ring topology and of the transmission of all the data over the same medium is the fact that a break at any point puts the entire network out of service. Components in a ring structure which have no data burden of their own beyond information for control and monitoring, e.g., remote controls, have an oversized interface.

Data transmission method having a data line which is separate from a data bus and is designed as a chain


A sub-array of slot-coupled microstrip antennas fed using microstrip lines on an opposing substrate. Also provided is an omni-directional antenna comprised of six of the sub-arrays arranged in a hexagonal fashion. The gain of the antenna is ˜6 dB with a 3 dB elevation beam width of ˜30 degrees. The design provides constant beam angle over frequency, which is important for frequency-hopping applications, and the potential to add beam control to mitigate jamming in different sectors.

Aperture-coupled microstrip patch antennas are desirable structures for use in wireless telecommunications. Their broad use is primarily due to ease of fabrication, low cost, and simplicity of design. These characteristics, combined with the straightforward integration with microstrip distribution networks, make them especially well suited for phased array applications.
High-gain omni-directional antennas find uses in several communications applications including those for small aerial vehicles. Several topologies for omni-directional radiators exist and include linear arrays using bifilar helical elements, periodic rod antennas, coaxial continuous transverse stub arrays (C-CTS), and patch arrays on a cylindrical body. These approaches typically suffer from beam-pointing variation over frequency, do not offer the capability for beam steering for attitude correction, and do not facilitate advanced beam-reconfiguration options such as eliminating coverage from certain sectors for jamming avoidance.