The present invention relates to allelic variants of the human Signal Transducer and Activator of Transcription-6 (STAT6) gene and provides primers and methods suitable for the detection of these allelic variants for applications such as molecular diagnosis, prediction of an individual's disease susceptibility, and /or the genetic analysis of the STAT6 gene in a population. Specifically, the invention provides a method for detection of predisposition to atopic disorders/other immunological disorders such as, autoimmune disorders, inflammatory disorders, fibrosis, etc. where STAT6 plays an important role by screening for human Signal Transducer and Activator of Transcription-6 (STAT 6) gene variants.

The genomic DNA of all organisms undergoes spontaneous changes in the sequence (termed as mutation) in the course of their continuing evolution thereby generating variant forms of progenitor sequences, which may lead to various evolutionary advantages or disadvantages to the survival of the organism. If such effects of the mutations or variations are not seen then they are termed as neutral changes/mutations. If the mutation is lethal then it is not transmitted to the following generations and thus the mutation is lost from the gene pool of that organism. A variant form may also confers an evolutionary advantage to the species and is eventually incorporated into the DNA of many or most members of the species, and hence, effectively it becomes the progenitor form. In many instances, both progenitor and variant form(s) survive and co-exist in the gene pool of the species. This coexistence. of multiple forms of a sequence gives rise to polymorphisms.
Several different types of polymorphism have been reported. A restriction fragment length polymorphism (RFLP) means a variation in DNA sequence that alters the length of a restriction fragment. The restriction fragment length polymorphism may create or delete a restriction site, thus changing the length of the restriction fragment. RFLPs have been widely used in human and animal genetic analyses. Other polymorphisms take the form of short tandem repeats (STRs) that include tandem di-, tri- and tetranucleotide repeated motifs. These tandem repeats are also referred to as variable number tandem repeat (VNTR) polymorphisms. VNTRs have been used in identity and paternity analysis and in a large number of genetic mapping studies. Other polymorphisms take the form of single nucleotide variations. Such polymorphisms are far more frequent than RFLPS, STRs and VNTRs. Some single nucleotide polymorphisms (SNPs) occur in protein-coding sequences, in which case, one of the polymorphic forms may give rise to the expression of a defective or other variant protein and, potentially, a genetic disease. Examples of genes, in which polymorphisms within coding sequences give rise to genetic disease include beta-globin (sickle cell anemia) and CFTR (cystic fibrosis). Other single nucleotide polymorphisms occur in noncoding regions. Some of these polymorphisms may also result in defective protein expression (e.g., as a result of defective splicing). Other single nucleotide polymorphisms have no phenotypic effects.
The effects of such polymorphisms can be at various levels of cellular organization. Polymorphic elements in the promoter and/or regulatory regions are known to modulate the levels of mRNA of the genes. Polymorphisms in the un-translated regions (UTR's) of the RNA have also been documented to regulate the transcriptional and translational rates of the genes. Their presence in the intron-exon boundaries can also lead to changes in splicing and or splice products that are formed from the native full length mRNA. Polymorphisms in the coding region may change the function of the protein if it is a non-synonymous change and if it occurs in a critical domain of the protein leading to functional changes of the protein.
Thus polymorphisms are useful in defining genomic regions (for example as genetic markers) and they may also lead to disease (for example functional polymorphisms). Numerous examples are documented in the scientific literature and persons trained in this field are familiar with it (please see Abney M et al, Am J Hum Genet 70:920-34, 2002; Baron M, Mol Psychiatry 6:143-9, 2001; Bodmer W F, Ciba Found Symp 130:215-28, 1987; Breslow J L, Physiol Rev 68:85-132, 1988; Caraballo L R and Hernandez M, Tissue Antigens 35:182-6, 1990; Levitt R C, Am J Respir Crit Care Med 150:S94-9, 1994; Xu J et al, Clin Exp Allergy 28 Suppl 5:1-5; discussion 26-8, 1998).
Atopic diseases are a clinically heterogeneous group of diseases characterized by elevated serum IgE levels and varying phenotypic expressions such as Asthma and Atopic Dermatitis (Barnes K C, Clin Exp Allergy 29 Suppl 4:47-511999; Barnes P J Respir Res 2:64-5, 2001; Blumenthal M N and Amos D B, Chest 91:176S-184S, 1987; Thomas N S et al, Am J Respir Crit Care Med 156:S144-51, 1997). Specifically, Asthma is a chronic airway disease, affecting 15-18% of the world's population.
It is mainly a childhood disorder though the age. of onset can vary and is seen to be 35-45 yr. in the general population. Another case of extrinsic asthma is observed where the age of onset is above 45 yr. and is mainly due to the age induced changes in the lung function. The pathophysiology of atopic asthma is well documented. It is a T helper type 2 (Th2) mediated disorder with cytokines such as interleukin-4, interleukin-5, interleukin-13, implicated in the deviation of the immune system towards atopicity. Increased levels of these cytokines lead to elevated total serum IgE levels, eosinophil recruitment, and bronchial hyper-responsiveness that ultimately culminate in asthma pathogenesis. These interleukins are also known to interact and stimulate the alveolar cells and bronchial smooth muscle cells resulting in the clinical phenotypes of bronchial hyper-responsiveness (Barnes P J, Respir Res 2:64-5, 1999). Gene-gene and gene-environment interactions have been implicated in the development of asthma (Tay et al, Asian Pac J Allergy Immunol 17:239-42, 1999; Bleecker E R, Am J Respir Crit Care Med 156:S113-6, 1997; Cookson W, Nature 402:B5-11, 1999).
Various genetic studies have shown multiple loci to be associated with the disease. Asthma is therefore a multigenic disorder with a number of genes contributing minor effects leading to pathogenesis. Linkage studies, in various populations, have narrowed down the presence of susceptibility or disease genes to chromosomal locations such as 1p31, 5q31-33, 1p13, 12q13-24, 13q14, 17q12-21. However, all the causative genes and mutations have so far not been identified (Bleecker E R et al, Am J Respir Crit Care Med 156:S113-6, 1997; Blumenthal M N, Chest 91:176S-184S, 1987, Duffy D L, Epidemiol Rev 19:129-43, 1997).
Moreover, there is evidence to suggest that ethnic differences exist in the susceptibility genes associated with asthma (Xu J et al, Am J Hum Genet 68:1437-46, 2001). Of these loci, 12q21-23 harbors the Signal Transducer and Activator of Transcription-6 (STAT6) gene (consisting of 23 exons spanning a region of 19 kbp) which is thought to be an important candidate gene. STAT6 plays a major role in the initiation of signals from activated Th2 cells, specifically through IL4 and IL13 receptors (Ihle J N, Curr Opin Cell Biol 13:211-7, 2001; Zhu J et al, J Immunol 166:7276-81, 2001; Horvath C M, Trends Biochem Sci 25:496-502, 2000). STAT6 has also been implicated in the differential expression of chemokines, such as eotaxin-1, eotaxin-2 and thymus and activation regulated chemokine (TARC) (Takeda K and Akira S, Cytokine Growth Factor Rev 11:199-207, 2000; Zhang S et al, J Immunol 165:10-4, 2000; Mathew A et al, J Exp Med 193:1087-96, 2001). It is expressed in activated T cells in response to anti-CD3 antibody, PMA and other mitogenic responses (Arinobu Y et al, Biochem Biophys Res Commun 277:317-24, 2000). Interleukin 4 Receptor alpha (IL4RA) mediated phosphorylation of the STAT6 leads to its dimerization and nuclear localization, where it binds to the promoter elements of the Cεimmunoglobulin gene and causes the expression of the ε-transcript (Paul W E, Ciba Found Symp 204:208-16, discussion 216-9, 1997; Nelms K et al, Annu Rev Immunol 17:701-38, 1999; Linehan L A et al, J Immunol 161:302-10, 1998; Yang M et al, Am J Respir Cell Mol Biol 25:522-30, 2001).
Two naturally occurring isoforms have been detected that may modulate IL4 induced functional responses and cellular proliferation (Sherman M A et al, J Immunol 162:2703-8, 1999; Mullings R E et al, J Allergy Clin Immunol 108:832-8, 2001). The significance of this pathway in the development of atopic responses has been demonstrated by the failure of STAT6 (−/−) mice to develop a Th2 response, including, a lack in IgE production and eosinophilia, and failure to develop airway hyper-responsiveness in response to antigen challenge (Akimoto T et al, J Exp Med 187:1537-42, 1998; Miyata S et al, Clin Exp Allergy 29:114-23, 1999; Tomkinson A et al, Am J Respir Crit Care Med 160:1283-91, 2002; Zhu J et al, J Immunol 166:7276-81, 2001). A STAT6 antisense oligonucleotide was also shown to down regulate the expression of the germline ε transcript in DND39, a human Burkitt lymphoma cell line (Hill S et al, Am J Respir Cell Mol Biol 21:728-37, 1999).
Case control studies in the Japanese population have shown that a dinucleotide repeat in the 5′ UTR of this gene to be associated with asthma and atopic disorders (Gao P S et al, J Med Genet 37:380-2, 2000; Tamura K et al, Clin Exp Allergy 31:1509-14, 2001). However, they have not found any association of the repeat size with the total serum IgE levels. Also, this observation has not been confirmed in a more stringent study on a Caucasian sib pair cohort (Duetsch G et al, Hum Mol Genet 11:613-21, 2002). Duetsch et al has sequenced the complete gene and have identified a set of 23 SNPs spanning the intronic region. They have however not identified a polymorphism in the coding region. They were not able to demonstrate a significant association of these polymorphisms with asthma. These two studies suggest that there is a component of ethnic variation that is involved and that depends on the particular population under study.
In an earlier case control study in the Japanese population, the R3 locus has been found to be associated with asthma (13 repeat allele) (Tamura K et al, Clin Exp Allergy 31:1509-14, 2001). However, in a sib pair study in a German population, no such association of the R3 locus with asthma was seen, although weak associations were observed for the total serum IgE levels and the eosinophil counts with the alleles 17 and 16, respectively (Duetsch G et al , Hum Mol Genet 11:613-21, 2002). The present results of the present study provide very unique and unexpected results as shown in the prior arts. The association of allele 15 with asthma in the population could be explained are based not only on the ethnic differences that exist between observed in the present population and the Japanese and the Caucasian populations, but found generally in any population of the world. The present has identified the variants, which exist in any type of population in the world irrespective of its origin, community, colour, geographical location or ethnicity. The inventors have compared allele frequencies at R1 and R3 loci, and their haplotypes, in a population (comprising population from both North and South parts of India), they observed that their distributions are significantly different (data not shown). Also, the sampling strategies used in the studies are different. The present study is a case control study although the inventors have recruited individuals with a familial history of asthma and atopy. Further, the invention clearly defines that the variants identified would be useful for any kind of population of any geographical origin.
It is apparent that the use of the R1 and R3 polymorphisms in the generation of haplotypes in conjunction with SNP data for this gene may yield more informative haplotypes. The haplotypes of SNPs obtained in the German population suggests that there may be a recombination hot spot in the gene (Duetsch G et al, Hum Mol Genet 11:613-21, 2002). Estimation of decay of LD across the putative recombination hot spot could have been important in defining functional aspects of this genomic region. In any event, if functional polymorphisms are present on the chromosomal background of specific haplotypes then haplotypes that describe parts of the STAT6 gene flanking the putative recombination hot spot may provide a better association with asthma and total IgE. However, this hypothesis remains to be tested in the future.
Both the R1 and R3 polymorphisms seem to be biologically relevant. Using promoter deletion analysis it has been shown that the RI locus is flanked by the critical transcription factor binding sites TFIIIA and the TATA box (Patel B K et al, Genomics 52:192-200, 1998). Moreover, di-nucleotide repeats are known to bind various minor groove-binding proteins, which can interact with the basal transcriptional complex may modulate transcription. Interestingly, it has been shown that dinucleotide repeats have a propensity for forming Z-DNA like structures and that in the promoter regions these are capable of regulating transcription, for example, in the rat nucleolin gene (Rothenburg S et al, Proc Natl Acad Sci USA 98:8985-90, 2001). Also, CA repeats in the intron are known to regulate gene expression, for example in the first intron of epidermal growth factor receptor gene and interferon gamma genes (Gebhardt F et al, J Biol Chem 274:13176-80, 1999).
Similarly, the 5′-UTR is known to regulate translation of various genes through interaction with protein factors or by pseudoknot formation (Mokdad-Gargouri R et al, Nucleic Acids Res 29:1222-7, 2001; Ben-Asouli Y et al, Cell 108:221-32, 2002). However, further experimental work needs to be done to provide a conclusive proof for these hypotheses. In this context, it is important to note that, as shown by other groups and in the present study, no coding variants of STAT6 gene were found (Heinzmann A Clin Exp Allergy 30:1555-61, 2000, Duetsch G et al, Hum Mol Genet 11:613-21, 2002, Nagarkatti R and Ghosh B, 2002, in press). Thus it is possible that the action of STAT6 may be mediated mostly by the transcriptional and translation modulation of its levels, rather than due to structural changes in the protein itself. Thus, based on the above evidence it appears that STAT6 may be an important modifier locus that plays a significant role in regulating the atopic phenotypes depending on the ethnic background of the patients.

Gene variants of signal transducer and activator of transcription-6 (STAT 6) variants and process of detection the same

Council of Scientific & Industrial Research


A battery separator configured for reducing acid stratification for an enhanced flooded battery. The battery separator for the enhanced flooded battery is configured to minimize acid stratification. The battery separator is comprised of a microporous membrane and an absorptive mat. The absorptive mat includes a 3-hour wicking height greater than 15 cm. Wherein the absorptive mat of the battery separator is configured to minimize acid stratification of the enhanced flooded battery.

Lead acid batteries have been popular, low cost rechargeable energy storage devices for more than a century. Despite low energy-to-volume ratio, a lead acid battery can provide high surge currents, which make it attractive for starter motors, automotive, forklifts, Uninterruptible Power Supply, etc. The two main types of lead acid batteries are flooded batteries ("not sealed") and valve regulated lead acid (VRLA) batteries ("sealed"). An "enhanced" flooded battery is an improved and more robust flooded lead acid battery, like for use in automobiles using "Idle-Start-Stop" technology. In this technology, the battery must provide power to maintain the car's electrical system when the alternator stops generating current. Other markets for this technology include automotive regenerative breaking and industrial opportunity charging (like Forklifts). Due to such demands, the technology needs a battery with fast charging and enhanced cycling capability. At present, "Start-Stop" vehicles use AGM (Absorbed Glass Mat) and EFB (Enhanced Flooded Battery), both supporting increased cycle life and fast charging capability.
The present disclosure may be designed to provide an added component to the existing enhanced flooded battery separator. The battery separator separates or divides the positive electrode from the negative electrode within a lead acid battery cell. The separator permits exchange of ions with least possible resistance, while preventing a short that will result from the positive and negative electrode touching each other. Flooded battery separators may be made from a porous matrix and may incorporate porous inorganic fillers such as Silica, Alumina, Zirconia, Mineral clays or others known to those skilled in the art. The flooded battery separator may also incorporate specific additives such as water loss mitigating substances, antioxidant substances and rubber latexes among other materials offering specifically desirable activity. The bulk of the separator may be comprised of crosslinked natural and/or synthetic rubber, organic polymers of varying molecular weight such as polyesters, polysulfones and polyolefins (typically of molecular weight between 300K and 12 MM). Other materials used to manufacture flooded battery separators include wet-laid and dry-laid nonwovens typically produced from polyester and/or glass fiber. In certain cases the nonwoven separator is coated with phenolic compounds to enhance oxidation resistance. Many such separators possess a laminate comprised of glass or polyester in the form of a scrim with an open pore structure attached to the side of the separator facing the positive plate. The laminate or scrim prevents the oxidation of the rubber or polymer from the oxidative potential of the positive electrode, thereby increasing the life of the separator.
Enhanced Flooded Batteries, also known as EFB batteries are an enhanced version of standard wet-flooded technology. These types of batteries should not be confused with standard flooded or AGM VRLA batteries. The primary benefits of EFB technology are improved charge acceptance and greater cyclic durability when operating in a reduced state of charge (typical of Stop Start applications). As an approximation, EFB batteries can provide up to 85,000 engine starts, compared to 30,000 starts from standard flooded product.
EFB batteries have been introduced as a lower tier option to AGM batteries in terms of performance, durability and cost. EFB technology relies on improvements to existing flooded technology through the addition of porous carbon additives in the plate manufacturing process. AGM batteries benefit from the inclusion of unique design features not found in wet-flooded batteries. These include glass mat separators, recombinant lid technology and higher pack pressures to facilitate improved cyclic lifespan. AGM batteries are better suited to meeting the demands of higher specification vehicles that include one or more of the following technologies: Start Stop, Regenerative Braking and Passive Boost.
Batteries that are used in a partial state of charge, such as Enhanced Flooded Batteries, that are used for Start/Stop applications, tend to have reduced lives because these batteries undergo acid stratification due to under-charging. As examples, and clearly not limited thereto, the disclosed issue of acid stratification may also be an issue for flooded deep cycle batteries and/or flooded deep cycle traction batteries. Flooded Deep Cycle batteries may be used in solar energy applications (these batteries rarely get enough overcharge to cause gassing, due to the undependability of the sun, and therefore tend to get stratified and have reduced life). Flooded Deep cycle traction batteries (i.e. for lift trucks) are typically subject to "opportunity charging". As such, these batteries also do not get enough charge at any one time, thus, minimal gassing and the acid becomes stratified.
In general, acid stratification-related failures occur when the electrolyte of a stratified battery having been concentrated at the bottom of the cell causes damage to both the positive and negative plates. The high concentration "heavy" acid concentration on the bottom of the cell increases positive grid corrosion and produces dense, inactive area of lead sulfate on the negative plate. In such a battery failure, the dense zone of heavily sulfated negative active material (NAM) at the bottom of the negative plate is separated from the healthy NAM near the top, by what the industry may refer to as a "tide-line". An unstratified cell has no visible tide-line. The unequal charge across the plates of a cell with severe acid stratification reduces CCA (cold cranking amps), and starting the engine is sluggish. Acid stratification typically occurs if the battery dwells at low charge (below 80 percent), never receives a full charge, and/or has shallow discharges. Driving a car for short distances with power-robbing accessories engaged contributes to acid stratification because the alternator cannot always apply a saturated charge. Large luxury cars are especially prone to acid stratification. Allowing the battery to rest for a few days or shaking the battery to create acid turbulence helps correct the problem. However, acid stratification cannot always be avoided.
However, with lead acid battery technology, and especially enhanced flooded lead acid battery technologies, there is always a need or desire for improvement. With growing energy demands of energy storage batteries and enhanced flooded batteries of start stop vehicles, there is a need for continued improvement of lead acid battery technology. The instant disclosure recognizes the need to provide lead acid batteries, and especially enhanced flooded lead acid batteries with reduced acid stratification issues.
The present disclosure may be designed to address at least certain aspects of the problems or needs discussed above by providing new and/or improved flooded battery separators and enhanced flooded batteries configured for reducing acid stratification.

Battery separator configured for reducing acid stratification for enhanced flooded batteries


A multi-ratio automatic transmission has a plurality of fluid operated clutching devices, a fluidic torque converter and a fluid operated torque converter clutch mechanism. During certain operational periods, a hot mode is invoked to eliminate certain heat sources and increase heat dissipation to thereby prevent the fluid temperature from exceeding a predetermined maximum temperature. The hot mode is invoked as a function of both the temperature of the transmission fluid and the rate of change of the fluid temperature.

This invention is related to computer controlled automatic transmissions. More particularly, the invention is concerned with a method used to determine the propriety of operating the transmission in what is known in the art of transmission controls as `hot mode`.
During certain vehicle operating conditions, transmission fluid temperatures can reach and exceed undesirable levels leading to fluid degradation and performance deterioration. In such situations, it is desirable and well known to take steps to prevent excessive temperatures by providing a hot mode of operation wherein various control actions are taken to decrease heat sources and/or improve heat dissipation. Generally, this involves application of the torque converter clutch to eliminate the major heat source, that being the characteristic losses of fluid coupling, and/or extending the shift points thereby increasing engine rpm and proportionally increasing transmission fluid flow through the transmission including the cooler lines.
Typically, entry into a hot mode is triggered by the transmission fluid temperature exceeding a predetermined threshold. The threshold is a compromise among many factors including undesirable peak fluid temperatures with high threshold calibrations, frequent and/or lengthy hot mode duration with low threshold calibrations, and mode cycling busyness.

Automatic transmission hot mode management


A filter arrangement for filtering fluid comprises a housing having an inlet and an outlet, a first cylindrical construction, a second cylindrical construction, and a bypass arrangement. The first construction includes filter media mounted within the housing. The first construction defines a first open filter interior. The first open filter interior includes a first dimension being a largest dimension across a cross-section of the first open filter interior. The second construction includes a filtration construction mounted within the housing. The second construction defines a second open filter interior. The second open filter interior includes a second dimension being a largest dimension across a cross-section of the second open filter interior. The second dimension is at least as large as the first dimension. The bypass arrangement has an open position and a closed position. In the open position, the bypass arrangement is constructed and arranged to permit fluid flow from the housing inlet through the second filtration construction; in the closed position, the bypass arrangement is constructed and arranged to disallow fluid flow from the housing inlet and through the second filtration construction.

Filters have been employed in a variety of applications including hydraulic systems, fuel systems, and engine lubrication systems. Such filters may generally be spin-on type filters and include a filter element within a can or housing having a cover or attachment plate at one end by which the filter can be screwed onto or off of a filter head. A central opening and several surrounding openings in the cover are typically provided to direct flow through the filter and filter element therein, which flow can be either an inside/out or outside/in direction relative to the filter element. A circular gasket on the outside of the cover serves as the external seal between the filter and the filter head, while another circular gasket on the inside of the cover functions as an internal seal between portions of the filter element and the cover. Spin-on filters are usually used only once before removal and replacement.
Eventually, the filter element becomes clogged requiring replacement of the filter. However, it is not always easily known when it is appropriate to change the filter. Sometimes, the filter element becomes clogged, and the fluid to be filtered backs up and causes problems in the system. Also, it can stop fluid flow to downstream system components. Because of this, in addition to problems created during cold starts and flow surge conditions, bypass valves have been equipped in the filter head. When the pressure in the spin-on filter exceeds a certain amount due to, for example, a clogged filter element, a cold start condition, or a flow surge, the bypass valve opens and permits fluid to continue downstream through the system. This can be problematic, as it allows completely unfiltered fluid which may have substantial contaminants therein to pass through the system. This can lead to transmission problems and/or damage to the components of an internal combustion engine.

Liquid filtration system incorporating a bypass filter element


A mounting device for a support unit for commercial vehicles includes at least one supporting area, a first fixing area and a second fixing area, wherein the supporting area is configured to absorb the supporting forces in the supporting direction from the support unit or a support tube, wherein the first fixing area and the second fixing area are configured to fix the mounting device to a semi-trailer, wherein the first fixing area has at least one hole, wherein the second fixing area has at least one hole, and wherein the holes are configured to receive a fastener.

The present invention relates to a mounting device for supporting devices, especially those of commercial vehicles, as well as a mounting bracket for a mounting device.
Supporting devices or support jacks are known in the prior art. They serve for bracing and/or adjusting the height of trailers, semi-trailers or vehicles. The supporting devices known in the prior art usually comprise to this end an outer and an inner support tube, which can be telescopically fitted together. For the mounting on a trailer, semi-trailer, or vehicle, mounting devices are provided on the supporting devices, which are arranged with integral bonding on a corresponding surface of the trailer, especially in the case of heavily loaded supporting devices. This integrally bonded fixation, which is usually done by welding on, results in large labor expense and poor flexibility in the case of heavy loading.
The problem which the invention proposes to solve is to provide a support unit which can be securely mounted with only slight expense and which can be subjected to large forces, especially dynamic forces.


A plasma display panel reduces a resonance space between a frit and dummy partition walls so as to suppress noise and smoothly supply and exhaust a discharge gas. The plasma display panel includes a front substrate and a rear substrate that face each other, address electrodes and display electrodes that are spaced apart from each other and each extend along directions intersecting each other between the front substrate and the rear substrate, and partition walls that form a display region while partitioning a plurality of discharge cells and form a non-display region along a periphery of the display region between the front substrate and the rear substrate. The non-display region includes a first dummy area in which dummy cells are partitioned by dummy partition walls extending from partition walls disposed in the display region, and a second dummy area in which dummy cells are partitioned by dummy partition walls spaced apart from the first dummy area.

1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel that can improve the structure of dummy partition walls disposed in a non-display region, prevent looseness of an outer end by providing a frit having a large width, and supply and exhaust a discharge gas while reducing noise.
2. Description of the Related Art
Generally, a plasma display panel (PDP) is a device in which vacuum ultraviolet rays emitted through gas discharge generated in discharge cells excite phosphors to realize images. The plasma display panel is a next-generation thin display device because it can have a high resolution and a large screen.
In the plasma display panel, a discharge cell is partitioned by partition walls formed in a stripe-shaped or lattice-shaped pattern between a front substrate and a rear substrate. The partition walls are formed in the discharge cells constituting a display region that substantially realizes an image and a portion of a non-display region surrounding the display region, and provides dummy cells that stabilize discharge of outermost discharge cells of the display region. The partition walls forming such dummy cells are referred to as dummy partition walls.
The front substrate and the rear substrate are attached to each other by a frit interposed therebetween, and the frit is spaced apart from the dummy partition walls at a distance that can be significant enough to generate a resonance space, which causes noise of the panel.
If the frit having a large width is used in order to reduce the resonance space, the frit may enter an exhaust tube and contaminate the panel. On the other hand, if only the partition walls are expanded in order to reduce the resonance space, the partition walls may reduce the supply and exhaust of the discharge gas and thereby reduce the panel's luminance.
The above-described partition walls are made by forming a partition wall layer with partition wall paste; patterning the partition wall layer using a sandblast method, a press method, and an etching method using photosensitive materials; and firing the patterned partition walls at a high temperature of more than 450° C. The partition walls are fired in order to remove impurities, binders, and the like contained in a partition wall material, and make the partition walls harder.
When firing the partition walls, all vehicle components existing in the partition wall paste are evaporated, and main components constituting the partition walls are contracted by coupling with one another.
In this case, if the lattice structure of the partition walls of the plasma display panel is rectangular, as shown in FIG. 12, tension occurs along a longitudinal side of the partition walls 110 when the partition walls are fired, and thus the partition walls are bent (see portions indicated by circles).
Also, since the balance of force is not uniformly maintained at the outermost end of the partition walls, the partition wall is lifted inward when firing and thus looseness occurs. Thus, the outermost end rises out of other portions. As a result, as shown in FIG. 13, a gap is generated between a front substrate 100 and the partition walls 110 (see a portion indicated by a circle). This gap causes noise due to a vibration when the panel is driven.


The present invention is directed to a locomotive comprising energy storage units, such as batteries, a prime energy source, such as a diesel engine, and an energy conversion device, such as a generator. The locomotive comprises one or more of the following features: a separate chopper circuit for each traction motor; energy storage units that can be switched from parallel to series electrical connections, an fluid-activated anti-lock brake system, a controller operable to control separately and independently each axle/traction motor, and a controller operable to control automatically a speed of the locomotive. The present invention includes an integrated system for monitoring, controlling and optimizing an electrically powered locomotive using a combination of sensors and software to provide feedback that optimizes power train efficiency and individual drive axle performance for a locomotive that utilizes one of several possible electrical energy storage systems to provide the tractive power. The net result is a locomotive that has an integrated system of control over all aspects of the locomotive power train including control over individual drive axles, especially during acceleration, braking and non-synchronous wheel slip.

Existing railroad locomotives are typically powered by diesel electric engines in which a diesel motor drives an electric generator to produce electric power to drive electric motors which in turn drive the drive wheels of the locomotive. The present inventor has disclosed the use of a gas turbine engine fueled by compressed natural gas in substitution for the traditional diesel engine in his U.S. Pat. No. 5,129,328 issued Jul. 14, 1992, and as a booster unit for the diesel engine in his U.S. Pat. No. 4,900,944 issued Feb. 13, 1990, both of which are incorporated herein by reference.
The use of energy storage batteries in combination with a generator is known for automobiles, buses and other road and highway vehicles. Such hybrid engines for vehicles are advantageous due to their increased fuel efficiency and reduced pollution. In those applications, it is important to minimize the weight of the batteries to maintain fuel efficiency. Electric batteries have been used to store electric power to drive electric locomotives as, for example, disclosed by Manns in U.S. Pat. No. 1,377,087 issued May 3, 1921 which is incorporated herein by reference. In Manns, three standard diesel engines are used to drive generators to charge the storage batteries. Such a system has not achieved commercial acceptance over existing diesel electric locomotives due to the added cost and complexity of providing multiple diesel engines in addition to the storage batteries.
The present inventor has also disclosed the use of a battery powered locomotive which has a ratio of energy storage capacity to charging power in the range of 6 to 40 hours in his U.S. Pat. No. 6,308,639 issued Oct. 30, 2001 which is also incorporated herein by reference.
The present inventor has also disclosed the use of individual chopper circuits associated with individual drive axles in his copending U.S. patent application Ser. No. 10,083,587 filed on Feb. 26, 2002.
There remains a need for a fuel-efficient locomotive which uses a combination of a small fuel-powered generator, a substantial energy storage capacity, and control systems that regulates and maintains the power train at maximum fuel efficiency and minimizes maintenance. Such control systems would also allow greater command over individual drive axles to help alleviate undesirable conditions such as non-synchronous wheel slippage and wheel locking.

Method for monitoring and controlling locomotives


A video recording/reproducing apparatus with tuner includes a microcomputer. The microcomputer determines as to having-station/having-no-station on CH3 and CH4 that usually have no station in the U.S.A. and then sets a frequency of a channel determined as having-no-channel to an RF modulating circuit. The microcomputer also sets a frequency of CH3 or CH4 to the RF modulator circuit 22 in response to manual operation by an operator only when both CH3 and CH4 are determined as having-station. This processing is implemented prior to the processing for tuner preset.

1. Field of the Invention
This invention relates generally to video recording/reproducing apparatuses with tuner and, more particularly, to a video recording/reproducing apparatus with tuner which re-modulates a television signal (base-band signal) outputted from the tuner by a frequency of a predetermined channel and then outputs a modulated television signal (radio frequency signal) to the video monitor with tuner, such as a television receiver.
2. Description of the Prior Art
The VTR (Video Tape Recorder) as one example of video recording/reproducing apparatuses with tuner has an RF output terminal provided for connection to an ANT input terminal of a television receiver. Where a television signal (base-band signal) on a channel selected by a VTR tuner is inputted to the television receiver through the RF output terminal, the television signal is modulated from a base-band signal to a radio frequency signal by a modulator circuit. At this time, where the modulation frequency is set at a frequency of CH3, the television receiver if its reception channel is set to the same CH3 provides display, on the TV screen, of a broadcast image through a channel selected by the VTR tuner. Also, where the modulation frequency is set at a frequency of CH4, the television receiver if the reception channel is set to CH4 provides display, on the TV screen, of a broadcast image through the channel selected by the VTR tuner.
Incidentally, the above explanation is on a premise that CH3 and CH4 are vacant channels (having-no-station channels) and the modulation frequency is set to the CH3 or CH4 frequency by the mechanical switch provided on the backside of the VTR.
In such a VTR, when presetting a having-station channel to a built-in tuner, the operator is required to carry out the following operations. First, the reception channel on the television receiver must be set to CH3 or CH4. Next, the VTR mechanical switch must be manipulated to set the modulation frequency to the reception channel frequency. This displays a menu picture including a tuner preset mode on the television receiver. If the operator selects a tuner preset mode, preset processing is commenced to preset a frequency of a having-station channel onto the tuner.
The prior art, however, requires the manipulation of a mechanical switch to be felt troublesome by an operator.

Video recording/reproducing apparatus with tuner


Mixed-signal circuitry, such as a digital-to-analog converter (DAC) device, performs a series of operation cycles. The circuitry has n circuitry segments (21, 41 to 2n, 4n) which together produce an analog output signal (IA-IB). In each cycle a transfer function morphing section (22) generates, in dependence upon a digital input signal (D1-Dm), a set of n segment control signals (T1-Tn) for application to respective ones of said segments to influence the produced analog output signal. The n segment control signals are caused to be applied to the n segments in at least two different orders at different respective times. At least one order differs from the next order by more than a starting ordinal position amongst the segments. Also, the changes in ordinal position of the segments brought about by the changes in order of application of the segment control signals are limited in number and/or magnitude relative to said number n of segments. This changes a transfer function (accumulated non-linearity error caused by amplitude and/or delay mismatches between the segments) between two or more different forms over the course of the operation cycles. This reduces the transfer function variation between different manufactured devices which in turn can provide an improvement in guaranteed minimum performance for a given manufacturing yield or an improvement in yield for a given performance.

1. Field of the Invention
The present invention relates to segmented circuitry such as, for example, digital-to-analog converters.
2. Description of the Related Art
FIG. 1 of the accompanying drawings shows parts of a conventional digital-to-analog converter (DAC) of the so-called xe2x80x9ccurrent-steeringxe2x80x9d type. The DAC 1 is designed to convert an m-bit digital input word (D1-Dm) into a corresponding analog output signal.
The DAC 1 includes a plurality (n) of identical current sources 21 to 2n, where n=2mxe2x88x921. Each current source 2 passes a substantially constant current I. The DAC 1 further includes a plurality of differential switching circuits 41 to 4n corresponding respectively to the n current sources 21 to 2n. Each differential switching circuit 4 is connected to its corresponding current source 2 and switches the current I produced by the current source either to a first terminal, connected to a first connection line A of the converter, or a second terminal connected to a second connection line B of the converter.
Each differential switching circuit 4 receives one of a plurality of control signals T1 to Tn (called xe2x80x9cthermometer-coded signalsxe2x80x9d for reasons explained hereinafter) and selects either its first terminal or its second terminal in accordance with the value of the signal concerned. A first output current IA of the DAC 1 is the sum of the respective currents delivered to the differential-switching-circuit first terminals, and a second output current IB of the DAC 1 is the sum of the respective currents delivered to the differential-switching-circuit second terminals.
The analog output signal is the voltage difference VA-VB between a voltage VA produced by sinking the first output current IA of the DAC 1 into a resistance R and a voltage VB produced by sinking the second output current IB of the converter into another resistance R.
In the FIG. 1 DAC the thermometer-coded signals T1 to Tn are derived from the binary input word D1-Dm by a binary-thermometer decoder 6. The decoder 6 operates as follows.
When the binary input word D1-Dm has the lowest value the thermometer-coded signals T1-Tn are such that each of the differential switching circuits 41 to 4n selects its second terminal so that all of the current sources 21 to 2n are connected to the second connection line B. In this state, VA=0 and VB=nIR. The analog output signal VA-VB=xe2x88x92nIR.
As the binary input word D1-Dm increases progressively in value, the thermometer-coded signals T1 to Tn produced by the decoder 6 are such that more of the differential switching circuits select their respective first terminals (starting from the differential switching circuit 41) without any differential switching circuit that has already selected its first terminal switching back to its second terminal. When the binary input word D1-Dm has the value i, the first i differential switching circuits 41 to 4i select their respective first terminals, whereas the remaining nxe2x88x92i differential switching circuits 41+1 to 4n select their respective second terminals. The analog output signal VA-VB is equal to (2ixe2x88x92n)IR.
FIG. 2 of the accompanying drawings shows an example of the thermometer-coded signals generated for a three-bit binary input word D1-D3 (i.e. in this example m=3). In this case, seven thermometer-coded signals T1 to T7 are required (n=2mxe2x88x921=7).
As FIG. 2 shows, the thermometer-coded signals T1 to Tn generated by the binary-thermometer decoder 6 follow a so-called thermometer code in which it is known that when an rth-order signal Tr is activated (set to xe2x80x9c1xe2x80x9d), all of the lower-order signals T1 to Tr-1 will also be activated.
Thermometer coding is popular in DACs of the current-steering type because, as the binary input word increases, more current sources are switched to the first connection line A without any current source that is already switched to that line A being switched to the other line B. Accordingly, the input/output characteristic of the DAC is monotonic and the glitch impulse resulting from a change of 1 in the input word is small.
It will be appreciated that the number of current sources 2 and corresponding differential switching circuits 4 in the FIG. 1 architecture is quite large, particularly when m is greater than or equal to 6. When m=6, for example, n=63, and 63 current sources and 63 differential switching circuits are required. In order to deal with such a large number of current sources, and to enable the thermometer signals to be delivered efficiently to the different differential switching circuits, it has been proposed to arrange the current sources and differential switching circuits as a two-dimensional array of cells, each cell including one current source and its associated differential switching circuit. This arrangement is shown in FIG. 3 of the accompanying drawings.
In FIG. 3, 64 cells CLij are arranged in an 8xc3x978 square array having eight rows and eight columns. In FIG. 3, the first digit of the suffix applied to each cell denotes the row in which the cell is located and the second digit of the suffix denotes the column in which the cell is located. Thus, the cell CL18 is the cell in row 1, column 8.
Each cell CLij includes its own current source 2 and its own differential switching circuit 4. The respective first terminals of the cells of the array are connected together to a first connection line A of the DAC and the respective second terminals of the cells of the array are connected together to a second connection line B of the DAC, as in the FIG. 1 DAC.
The numbers allotted to the cells CLij in FIG. 3 denote the sequence in which the cells are activated (or controlled) to change from selecting their respective second terminals to selecting their respective first terminals. The activation sequence follows the physical order of the cells in the array, starting from row 1 and activating the cells of that row sequentially in column order, followed by row 2, and so on for each successive row of the array.
One problem which arises in the FIG. 3 arrangement is that, although the output currents of the respective current sources 2 of the different cells of the array should be uniform, in practice the actual output currents of the cells suffer from non-uniformity arising from various causes.
For example, a voltage drop along a power supply line can cause a graded error along a row or column, as shown in FIG. 4(A) of the accompanying drawings. In this case, the current sources in the first four cells of the row or column concerned may have negative errors, signifying that each of them produces a below-average output current. These negative errors decrease towards the centre of the row or column concerned. The current sources in the remaining cells 5 to 8 of the row or column concerned have respective positive errors, signifying that each of them produces an above-average output current. These positive errors increase from the centre of the row or column to the end.
Thermal distribution inside a chip including the array can cause a symmetrical error within a row or column, as shown in FIG. 4(B) of the accompanying drawings. In this case, the current sources in the end cells 1, 2, 7 and 8 of the row or column have negative errors, whereas the current sources of the central cells 3 to 6 of the row or column have positive errors.
In addition, there can be other types of error such as random errors, discussed in more detail below. The final error distribution for the cell array is produced by superposing all the different error components.
The graded and symmetrical errors shown in FIG. 4(A) and FIG. 4(B) tend to accumulate and result in a large integral linearity error (INL). For example, imagine that the graded error distribution shown in FIG. 4(A) exists within the first row of the cell array shown in FIG. 3. In this case, as cells 1 to 4 are progressively activated (changed from selecting their respective second terminals to selecting their respective first terminals) the negative errors accumulate, amounting to a significant total negative error when the digital input code is 4. Only when cells 5 to 8 are sequentially activated do the positive errors attributable to these cells start to cancel out the large negative error attributable to cells 1 to 4.
Of course the situation is even worse if there are graded errors corresponding to FIG. 4(A) along each of the columns 1 to 8. In this case, as cells 1 to 8 are progressively activated, the largest negative error (the error at position 1 in FIG. 4(A)) occurs for each of the eight cells of row 1. Similarly, in row 2, negative errors corresponding to position 2 in FIG. 4(A) accumulate eight times. Thus, by the time the input code has increased to 32 (corresponding to all of the cells in rows 1 to 4 being activated) the accumulated negative error is very large indeed.
Similar problems arise with the accumulation of symmetrical errors of the kind shown in FIG. 4(B).
Mismatches due to graded and symmetrical errors can be reduced by selecting the cells in a special sequence different from the sequence in which they are arranged physically in the cell array. In particular, a special cell selection sequence conforming to the sequence of numbers in a so-called xe2x80x9cmagic squarexe2x80x9d is described in the assignee""s U.S. Pat. No. (CPA) 6,236,346, the entire content of which is incorporated herein by reference.
However, even when such a special cell selection sequence is employed, there inevitably remains a mismatch between the respective currents produced by the different segments. This in turn causes non-linearity in the performance of the DAC.
It has been proposed in a paper entitled xe2x80x9cStructural Optimization and Scaling of SC Delta-Sigma ADCSxe2x80x9d, Jesper Steensgaard, Delta-Sigma Data Converters Lecture Course, Mar. 16-19, 1999, San Diego, Calif., to employ element (or segment) rotation to shape mismatches between the elements of a DAC. In this proposal, the elements are rotated using data-directed rotation amounts. Another paper from the same lecture course, entitled xe2x80x9cMismatch-Shaping Multibit DACs for Delta-Sigma ADCs and DACs, Ian Galton, discloses mismatch shaping techniques which move noise from low frequencies to high frequencies to improve the noise shape. In these techniques the noise increases rapidly with frequency at high output-signal frequencies, so large oversampling ratios (e.g. 8 or 25) must be used to obtain useful results. A further paper from the same lecture course, entitled xe2x80x9cUnconventional Applications of Noise-Shaping Techniquesxe2x80x9d, Bob Adams, discloses that element xe2x80x9cscramblingxe2x80x9d can be employed in a sigma-delta DAC to turn distortion into shaped noise. The scrambling can be either random, which distributes the noise evenly across the entire frequency spectrum both within and outside the desired range of frequencies of the output signal, or data-directed which moves the noise away from DC but has noise that increases in amplitude progressively with frequency.
A technique has also been proposed, in the assignee""s European patent publication no. EP-A-1100203 (corresponding to the assignee""s co-pending U.S. patent application Ser. No. 09/708677), the entire content of which is incorporated herein by reference, which employs segment rotation, by amounts which are not data-directed, to shape mismatches between the segments of a DAC in order to shift noise out of a particular band of interest.
The above-described techniques are employed in order to overcome or alleviate the problems caused by graded, symmetrical and random errors in the segment sources of a particular device. However, there still remains a significant variation in performance from one device to the next due to the random source mismatches, as will now be described in more detail.
FIG. 5(A) of the accompanying drawings is a graph in which line S illustrates how an analog output signal varies with the binary input signal D1-Dm in an example bipolar DAC device. Line L1 represents the ideal input-output behaviour in such a device, where the analog output accurately follows the digital input in a linear fashion. As described above, in a real device various errors are inevitably present which cause the actual output analog signal to depart from ideal (line L1), as follows. The errors have been exaggerated for the purposes of this illustration.
An offset error causes the idealised output signal represented by line L1 to shift up by a certain amount EO for all digital input values, as illustrated by line L2. A gain error alters the gradient of the response curve to cause the offset error line L2 to rotate by an amount EG as illustrated by line L3. Finally, residual errors such as random errors, arising from source mismatches, cause the actual analog output signal to depart from line L3 by residual (random) error amounts ER which vary as the binary input signal varies. The lines L1, L2 and L3 are of course artificial representations used for the purposes of this explanation, with the line L3 drawn so as to pass through the actual analog output signal values (A and D in FIG. 5(A)) at the extremities of the digital input range.
FIG. 5(B) of the accompanying drawings is a plot corresponding to FIG. 5(A) but showing the difference in output-signal value between lines S and L3 in FIG. 5(A) as the digital input signal is varied. Thus, the plot of FIG. 5(B) represents graphically the extent of the departure of the actual output signal of FIG. 5(A) from linearity; FIG. 5(B) does not take into account the offset and gain errors EO and EG mentioned above. The plot in FIG. 5(B) therefore shows the departure from the artificial linearity represented by line L3 which is constructed so as to be coincident with line S at points A and D, and not the departure from the ideal linearity represented by line L1. The plot in FIG. 5(B) also returns to zero at points B and C where the line S crosses line L3.
Such a plot as that in FIG. 5(B) for a particular DAC device is referred to herein as the xe2x80x9ctransfer functionxe2x80x9d of the device. Since the horizontal axis represents a digital input signal incrementing by discrete steps, the transfer function actually varies in a stepwise fashion.
An equation defining the transfer function (non-linearity error) E can be derived by considering the FIG. 1 DAC in more detail. Although the n current sources 21 to 2n ideally generate identical currents I, in practice the current sources will have respective current errors e1 to en which may be positive, negative or zero. The DAC of FIG. 1 has a differential output signal IA-IB, where for a digital input-signal value (D1-Dm) of x:                               I          A                =                              ∑                          i              =              1                        x                                          (                          I              +                              e                i                                      )                                                            I          B                =                              ∑                          i              =                              x                +                1                                      n                                          (                          I              +                              e                i                                      )
with associated errors E(IA) and E (IB) given respectively by:                               E                                (                          I              A                        )                          =                              ∑                          i              =              1                        x                                          e            i                                                            E                                (                          I              B                        )                          =                              ∑                          i              =                              x                +                1                                      n                                          e            i
such that the overall error E(I) is given by:   μ  =            (                        ∑                      i            =            1                    n                                  e          i                    )        /    n
In this expression for the error E(I), the offset error EO described above with reference to FIG. 5(A) has been ignored. The gain error EG described above with reference to FIG. 5(A) can also be eliminated from this expression for E(I) by considering the mean xcexc of the errors e1 to en:       E              (      I      )        =            E                    (                              I            A                    -                      I            B                          )              =                            E                                (                          I              A                        )                          -                  E                                (                          I              B                        )                              =                                    ∑                          i              =              1                        x                                          e            i                          -                              ∑                          i              =                              x                +                1                                      n                                          e            i
A non-zero value of the mean xcexc for a device causes the gain error EG described above with reference to FIG. 5(A), since every current source contributes, on average, an error of xcexc to the line A or B to which it is connected, resulting in an overall change in the slope of the input-output response. The gain error EG can be eliminated from the expression for the error E(I) by subtracting the mean error xcexc from each of the current source errors ei as follows.
The sum of the errors (relative to the mean error xcexc) of current sources 21 to 2x connected to line A is:       E    A    =            ∑              i        =        1            x                  (                        e          i                -        μ            )
Similarly, the sum of the errors (relative to the mean error xcexc) of current sources 2x+1 to 2n connected to line B is:       E    B    =            ∑              i        =                  x          +          1                    n                  (                        e          i                -        μ            )
Thus, the transfer function E can be expressed as:                     E        =                              E            A                    -                      E            B                                                  E        =                                            ∑                              i                =                1                            x                                                  e              i                                -                      x                                      xe2x80x83                                    μ                    -                      (                                                            ∑                                      i                    =                                          x                      +                      1                                                        n                                                                  e                  i                                            -                                                (                                      n                    -                    x                                    )                                                μ                                      )                                                  E        =                                            ∑                              i                =                1                            x                                                  e              i                                -                                    ∑                              i                =                                  x                  +                  1                                            n                                                  e              i                                +                                    (                              n                -                                  2                                    x                                            )                                    μ
When x=0, all of the errors e1 to en are connected to line B which means that EA is zero. EB is also zero because by definition the sum of the line-B errors e1 to en is simply equal to n times the mean error xcexc. Thus, E=0 as represented by point A in FIG. 5(B).
Similarly, when xxe2x88x92n, all of the errors e1 to en are connected to line A which means that EB is zero. EA is also zero because the sum of the line-A errors e1 to en is by definition nxcexc. Thus, again E=0 as represented by point D in FIG. 5(B).
For all other values of x, the errors will be connected in different combinations to lines A and B with the result that the transfer function E is in the form of a xe2x80x9crandom walkxe2x80x9d which always starts and ends at zero and can be positive, negative or zero at points in between.
When the input value changes from xxe2x88x921 to x, the current source 2x changes from being connected to line B to being connected to line A, increasing EA by (exxe2x88x92xcexc) and decreasing EB by (exxe2x88x92xcexc). Thus, each step in the random walk of the transfer function E is 2 (exxe2x88x92xcexc).
Accordingly, the transfer function E can be regarded as the accumulated current-source errors, relative to the mean current-source error, for the particular DAC device. Choosing to make E zero at x=0 and n is simply equivalent to choosing to draw a line L3 through the actual output-signal values at points A and D in FIG. 5(A).
The transfer function causes unwanted distortion in the output of a DAC, to varying degrees and effects according to the exact shape of the transfer function. For example, a transfer function of the form shown in FIG. 6(A), which bows upwards (or downwards) in a single arc, will lead to the generation of unwanted second harmonics in the output signal. A transfer function of the form shown in FIG. 6(B), which is an S-shape passing through the zero-error axis at or near the mid-point, will lead to the generation of unwanted third harmonics in the output signal.
The current-source errors ei conform to a Gaussian (or normal) distribution. When DAC devices are manufactured the transfer functions E of the manufactured devices will also differ one from the next in accordance with the Gaussian distribution of current-source errors.
FIG. 7(A) of the accompanying drawings shows the transfer functions of six example DACs. In each individual DAC device the current source errors conform to a Gaussian distribution, and the current-source error distribution will be similar from one device to the next but with some deviation between devices, as shown in FIG. 7(B) of the accompanying drawings. The more segments there are in each device, the more similar the current source error distributions of different devices will be, but since the errors will be arranged (or selected) in a different order from one device to another, the transfer function of one device will almost always be different from that of another.
As a result of the fact that the transfer function differs from device to device, so too will the distortion in the output signal differ from device to device under the same input signal conditions. For example, for a DAC generating as its output signal a 100 MHz sine wave, the second harmonic would be a discrete tone at 200 MHz with a typical amplitude of, for example, xe2x88x9255 dBc (i.e. xe2x88x9255 dB relative to the main signal). However, since the transfer function is not the same from device to device as explained above, the amplitude of this second harmonic will typically vary from device to device by up to xc2x110 dB. Other distortion components caused by the non-linear output response of the device will also vary from device to device by a similar magnitude.
This device-to-device performance variation of several dB either side of typical has important consequences in terms of the manufacturing yield which can be achieved for the device.
From the point of view of the manufacturer of the devices, an assessment needs to be made of a trade-off between device yield and guaranteed minimum device performance (for example, a minimum signal-to-noise ratio in a particular frequency band of interest). Device-to-device performance variation means that the minimum performance must be specified as several dB worse than typical. One implication of this is that production testing and screening is required. Even allowing for some yield loss to reject the worst devices, the specification has to be reduced. Based on well-known device yield curves, it is known, for example, that if a guaranteed minimum noise performance figure is quoted based on a xe2x80x9cmean-2"sgr"xe2x80x9d figure (produced by subtracting twice the standard deviation "sgr" from the mean value), approximately 97% of manufactured devices will meet or exceed the guaranteed performance, i.e. the yield will be 97%.
If, instead of using a xe2x80x9cmean-2"sgr"xe2x80x9d figure, the manufacturer quotes the guaranteed performance based on a more modest xe2x80x9cmean-3"sgr"xe2x80x9d figure, the yield will increase to 99.9%, making the unit cost lower, but of course the quoted performance will also be lower, making the device less attractive to customers. If the manufacturer quotes the guaranteed performance based on a more demanding xe2x80x9cmean-3"sgr"xe2x80x9d figure, the yield will drop to approximately 84%, raising the unit cost, but the quoted performance will be higher, making the device more attractive to customers. The xe2x80x9cmean-2"sgr"xe2x80x9d figure is often a sensible trade-off, in that it gives an attractive performance level for customers whilst keeping the yield desirably high so that the unit cost is economic.
It is therefore desirable from the manufacturer""s point of view to reduce a device-to-device performance variation caused by differing transfer functions, so as to permit a better minimum performance to be specified by the manufacturer and/or an improved yield for a given minimum performance level.
In practice, it can often be difficult to assess the effects of using the above-mentioned techniques on the distortion components caused by segment mismatches, and empirical checks may be desired in order to select the most appropriate parameters to suit a particular application, or alternatively to test that the desired effect is being achieved by a particular set of parameters. It is therefore desirable to provide a means of facilitating the empirical selection or confirmation of such parameters.
An embodiment of one aspect of the present invention provides mixed-signal circuitry which is operative to perform a series of operation cycles. n circuitry segments together produce an analog output signal. Control signal generating circuitry is operable in each cycle to generate, in dependence upon a digital input signal, a set of n segment control signals for application to respective ones of the segments to influence the produced analog output signal. Morphing circuitry causes the n segment control signals to be applied to the n segments in at least two different orders at different respective times. At least one order differs from the next order by more than a starting ordinal position amongst the segments and that the changes in ordinal position of the segments brought about by the changes in order of application of the segment control signals are limited in number and/or magnitude relative to the number n of segments.
An embodiment of another aspect of the present invention provides a noise shaping method for use in such mixed-signal circuitry.
There are many different ways in which the number and/or magnitude of the ordinal position changes can be limited.
In terms of numbers of segments, in one embodiment, for each change in order there is at least one segment that is not changed in ordinal position. In another embodiment, for each change in order at least n/16 segments are not changed in ordinal position. In other embodiments, the numbers of segments changing are limited further still. For example, for each change in order at most n/2 segments may have a change in ordinal position, or at most a pair of segments may change ordinal position.
It is also possible to express the limitation in terms of an overall extent of the changes of ordinal position brought about by each change in order. For example, each change from one order to the next may be considered to have an associated segment change parameter, calculated by summing over all n segments the respective ordinal position changes, if any, brought about by the change in order concerned. The limits may then be expressed in terms of the values of the segment change parameters. In one embodiment the respective segment change parameters associated with the changes in order are each less than n2/4, more preferably each less than or equal to 16 n, and more preferably still each less than 2 n. In another embodiment an average value of the segment change parameter per cycle is less than n2/64, more preferably less than 16 n, and more preferably still less than 2 n. In another embodiment a difference between respective minimum and maximum values of the segment change parameter is limited relative to the number n of segments. For example, the difference may be less than n2/64, more preferably less than 16 n, and more preferably still less than 2 n. It may even be zero.
In practice, to keep complexity down the order of application of the segment control signals to the segments in any one cycle is preferably selected from among a plurality of predetermined available orders. The total number of predetermined available orders is preferably greater than 4, more preferably greater than n. The higher the number of available orders the greater the reduction in transfer function variation.
Each one of the predetermined available orders may be selected in turn in a predetermined order but preferably, to reduce the magnitudes of the noise components (whilst spreading them out), each one of the available orders is selected on a random or pseudo-random basis. In one embodiment, changes in order that involve more limited overall changes in ordinal position are caused to occur on average more often than changes in order that involve greater overall changes in ordinal position. This helps to keep a limit on the variation in value of the segment change parameter. In another embodiment the predetermined available orders are such that all changes in order involve approximately the same overall changes in ordinal position, i.e. approximately the same value of segment change parameter, and all changes in order are caused to take place on average with approximately the same frequencies.
One preferred way of changing the orders without making the circuitry too complex, and without the overall changes in ordinal position being too large, is swap the respective ordinal positions of segments belonging to one or more preselected pairs of segments.
An amount by which the noise components are spread out is influenced by an average time interval between repetitions of a given change in order. In one embodiment this average time interval is at least 0.1 xcexcs.
The n segments may be sub-divided into m groups of segments, where mxe2x89xa72. In one embodiment m=8 or 16 when n=128. When groups are formed the ordinal positions of segments belonging to the same group only may be changed, e.g. swapped. In this case, to limit the numbers of segments that change ordinal position changes in ordinal position may be permitted in mxe2x88x921 or fewer of the m groups at any one time, for example in only one group at any one time. In order that segments can move to ordinal positions spanning over the range of n possible ordinal positions when the orders are changed, the ordinal positions of segments belonging to the same group are preferably spread out (e.g. evenly) over the range of n possible ordinal positions.
An embodiment of another aspect of the present invention provides segmented circuitry which comprises a plurality of circuitry segments, each having a first analog quantity defining portion which defines a first analog quantity for its segment, and also having a second analog quantity defining portion which defines a second analog quantity for its segment. The second analog quantity is less well-defined than the first analog quantity for the segment concerned. Analog quantity selecting circuitry selects the first analog quantities or the second analog quantities. Combining circuitry produces a combined analog quantity based on the respective selected analog quantities of a combination of the circuitry segments.
The segmented circuitry described above may also be operative to perform a series of operation cycles, and in this case may further comprise control signal generating circuitry which in each cycle generates, in dependence upon a digital input signal, a set of segment control signals for application to respective ones of the segments to influence the combined analog quantity. Noise shaping circuitry causes the segment control signals to be applied to the segments in at least two different orders at different respective times, thereby to convert distortion, caused by mismatches between the first analog quantities of different segments, into noise components at preselected desired frequencies.
In a method of testing this segmented circuitry according to an embodiment of another aspect of the present invention, the analog quantity selecting circuitry is caused to select the second analog quantities, the operating parameters of the noise shaping circuitry, used by the noise shaping circuitry to influence the different orders, are set, and measurements are carried out on a signal derived from the combined analog quantity so as to identify the positions in a frequency spectrum of that signal of the noise components.

Abstract: Segmented circuitry having segments with well-defined and less-well-defined analog quantities is also disclosed (FIG. 29). The well-defined quantities are selected in use of the circuitry and the less-well-defined quantities are selected in a testing or setting up mode.


A method and arrangement for performing a memory built-in self test (MBIST) of an external memory and an internal memory of a network interface controller includes a series of burst write and burst read operations if an external memory is detected. The sequence of burst operations tests the back-to-back burst write, back-to-back burst write burst read, back-to-back burst read and back-to-back burst read burst write capabilities of the external memory, to thereby fully exercise the external memory. Additionally, the internal memory is tested by single write and single read accesses.

The present invention relates to the field of network communications, and more particularly, to the testing of an external system memory of a network interface controller.
Local area networks use a network cable or other media to link stations on the network. Each local area network architecture uses a media access controller (MAC) enabling network interface cards at each station to share access to the media.
Conventional local area network architectures use media access controllers operating according to half-duplex or full-duplex Ethernet (ANSI/IEEE standard 802.3) protocol using a described network medium, such as 10 BASE-T. Newer operating systems require that a network station be able to detect the presence of the network. In an Ethernet 10 BASE-T environment, the network is detected by the transmission of a line pulse by the physical layer (PHY) transceiver. The periodic link pulse on the 10 BASE-T media is detected by a PHY receiver, which determines the presence of another network station transmitting on the network medium based on the detection of the periodic link pulses. Hence, a PHY transceiver at station A is able to detect the presence of station B, without the transmission or reception of data packets, by the reception of link pulses on the 10 BASE-T medium from the PHY transmitter at station B.
Architectures have been developed enabling computers to be linked together using conventional twisted pair telephone lines instead of established local area network media such as 10 BASE-T. Such an arrangement, referred herein as a home network environment, provides the advantage that existing telephone wiring in a home may be used to implement a home network environment. However, telephone lines are inherently noisy due to spurious noise caused by electrical devices in the home, for example dimmer switches, transformers of home appliances, etc. In addition, the twisted pair telephone lines suffer turn-on transients due to on-hook and off-hook and noise pulses from the standard POTS telephones, and electrical systems such as heating and air conditioning systems, etc.
It is therefore important for a MAC to be informed of the conditions existing on a network at any time, and this is especially true in home network architectures. The status information is normally stored by the network controller in an external memory. In addition to the status information, the external memory also stores frame data and control information. The external memory, along with the PC board traces and connections, as well as parts of the logic within the network controller, comprise a memory subsystem. Failures in the memory subsystem may result from electrical or mechanical failure of any of the elements of the system and/or errors in the design of the PC board such as excessive loading or trace length.
In many networking and other products, an embedded memory built-in self test (MBIST) circuit is used to test the internal static random access memory (SRAM) at speed. Normally, this MBIST is a relatively simple circuit to read or write one memory location at each access. In more recent networking products, external SRAM has been more frequently employed in order to store the enormous amount of data required in networking applications. The external memories (SRAM) include different types of SRAM, including pipeline burst SRAM (or PB SRAM), No Bus Latency SRAM (or NoBL SRAM) and Zero Byte Turnaround SRAM (or ZBT SRAM).
For improved performance the above types of external memories allow bursting capability such that every external memory access may initiate multiple (e.g. four) memory locations consecutively. However, using a conventional MBIST that performs single write and single read accesses to test a burst type external memory does not fully test the external memory, since it fails to test the burst operations of the external memory.
There is a need for a method and arrangement for performing a built-in self test of both internal and external memory of a network interface controller, that adequately tests the capabilities of both types of memories.
This and other needs are met by embodiments of the present invention which provide a method of testing a memory arrangement of a network interface controller comprising the steps of determining whether the memory arrangement includes an external memory and an internal memory in relation to the network interface controller, and conducting a memory built-in self test (MBIST). When the memory arrangement includes both an external memory and an internal memory, the MBIST is conducted by performing back-to-back burst writing and reading operations on the external memory, and single accesses of external memory, followed by performing single accesses of memory locations of the internal memory. When the memory arrangement includes only an internal memory, the MBIST is conducted by performing single accesses of memory locations of the internal memory.
By performing back-to-back burst writing and reading operations, and single accesses of the external memory in the MBIST, adequate testing of the capabilities of the external memory is achieved. The test thus accounts for the burst capability of external memories used in network applications. In certain embodiments of the invention, the additional testing capability for external memories is added to a MBIST already used for testing internal memories with single accesses. This requires less hardware and does not add cost to a chip, such as a network interface controller.
The earlier stated needs are also met by another embodiment of the present invention which provides a network interface controller arrangement comprising a network interface controller having an internal memory, an external memory interface configured to couple an external memory to the network interface controller, and a memory built-in self test (MBIST) controller coupled to the internal memory and the external memory interface. The MBIST controller is configured to detect the presence of an external memory coupled to the external memory interface, and to conduct a MBIST on a detected external memory through the external memory interface and on the internal memory. The MBIST comprises back-to-back burst write and read operations on a detected external memory and single accesses of memory locations of the internal memory.
The foregoing and other features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

Method and apparatus for exercising external memory with a memory built-in self-test


An open-ended pipe engagement device with a saddle portion that attaches around an open pipe, a structural platform comprising a tapering plug, support bars to prevent dislodgement of the device and threaded rods to winch the platform and plug onto the pipe end to be sealed. The device provides a means to safely cap and plug a leaking pipe end and allow the pipe to resume normal activity thereafter. The saddle portion provides a structural a base from which the plug and associated platform are positioned and winched into place, counteracting any fluid pressure exiting the leaking pipe. The plug comprises a tapering and conforming structure with a centrally located through hole for which to direct fluid as the platform is lowered and once the plug is engaged. Above the plug and through the platform is a section of pipe for which to direct the leaking fluid after the apparatus has been secured to the end of the pipe, effectively controlling the leak and allowing normal operation of the well to resume.

1. Field of the Invention
The present invention relates to pipe plugs and devices utilizing a drive means to insert a plug into an open-ended pipe. More specifically, the present invention relates to an apparatus and method that forcibly inserts a tapered plug into a pipe end to eliminate leaking fluid therefrom, comprising a pipe saddle surrounding the pipe and a means for drawing the plug into the open pipe using a safe and reliable method that allows normal operation to be resumed shortly after its application.
2. Description of the Prior Art
Hydrocarbon drilling and production operations involve drilling deep within the ground to reach natural reserves for extraction. These drilling operations involve immense downhole well pressure, as the deposits are under considerable pressure in their natural state prior to being extracted. This creates potential safety hazards for the operators involved in the drilling process, a potential hazard for the environment and risk for equipment utilized in the process if safety measures are bypassed or overcome. If a drilling operation is not carefully managed and operated, an event known as a well blowout can occur. A well blowout involves an uncontrolled release of crude or natural gas from a well after pressure control and other safety systems have failed to properly activate. These situations lead to dispersement of petroleum products and other downhole matter into the local environment, which creates contamination issues that can kill local wildlife and create a flammability risk for nearby well workers. Uncontrolled or lengthy well blowouts can be catastrophic for a region and devastating to the local ecosystem. These events are also extremely costly, from the perspective of the well owner and the local populous that has to live in proximity to such wells.
Adequate safety measures are therefore in place to prevent such occurrences; however blow outs are still a concern for the drilling and petroleum industry, as their results can have disastrous consequences for those directly involved, as well as for those downstream from the event that rely on a given habitat for food and jobs. Of particular concern with regard to the present invention are deep water drilling activities, wherein wells are accessed several thousand feet below the ocean surface. This type of drilling has increased in recent years, and has included some notable blowout events that have crippled entire regions and caused considerable damage to the local environment.
Safety measures to combat these risks include blowout preventer devices, which are most commonly categorized into the ram or annular blowout preventers. These devices have been developed to prevent blowout events and to deal with the varying pressures and uncontrolled flow of fluid from a downhole well during drilling. They comprise large, specialized valves used to seal oil and gas wells. While fulfilling a given requirement when in operation, these devices are not completely foolproof, and have been known to fail.
The present invention comprises a device designed to seal a leaking well or pipe after a blowout or leak has occurred. The devices currently available in the prior art lack the ability to securely and safely plug a gushing pipe under high pressure, and to allow the continued operation of the pipe thereafter. The present invention is adapted to couple with an open pipe end using a saddle device, which surrounds the circumference of a pipe and provides a base for which to winch down a sealing structure that further comprises a platform having a blowout plate, a pipe plug, placement for working vehicles or tools and an orifice to direct the leaking fluid into an attached pipe. The platform is a large, three sided structure that supports the plug and directs the high pressure fluid through its central orifice during operation. Between the platform and the saddle are vertical support arms that are utilized to provide stability and prevent separation between the pipe end and the platform as the two are engaged. A set of threaded rods are utilized to draw the platform towards the open pipe, slowly closing the gap between the plug and the open pipe until the plug engageably seats therein, sealing the leak and routing the pipe fluid into an attached pipe above the platform. The rods are controlled by a powered drive means, such as a rotary drilling tool that allows the rods to rotate and advance the platform closer to the pipe.
The primary goal of the present invention is to engage a leaking pipe in a controlled and safety-conscious manner, utilizing a device that can be carefully controlled and lowered onto a leaking pipe end for closure thereof. The device employs redundant means to prevent dislocation during operation, which could lead to further problems. It also allows for continued operation of the pipe after engagement of the device. In this way, the well experiences minimal downtime while reducing the amount of dispersed petroleum therefrom.
Devices in the art have been disclosed for pipe plugs with varying structural features and designs. While these devices may satisfactorily fulfill a given requirement, they fail to describe the structural elements of the present invention, its spirit or its method for capping to and plugging a leaking pipe end.
U.S. Pat. No. 5,904,377 to Throup describes a pipe fitting adapted to install within an aperture of a fluid container. The device comprises an inner and outer co-axial sleeve member, along with a split, helically wound washer. The device is adapted to envelope a pipe and provide a plug for an aperture along its outer surface. This device is useful for plugging holes in the surface of a pipe, but is not adapted to engage the end of a pipe and provide a plug to prevent fluid leakage therefrom.
U.S. Pat. No. 4,584,162 to Yoli describes a plug designed to close steam lines in a boiling-water reactor. The device comprises an elongated rubber member that is compressed by axial compression in order to form a seal that holds the plug in place within the pipe and prevents leaking steam therefrom. The mechanism for achieving the plug seal is similar to the present invention, wherein drive screws draw a platform having a plug into the end of a pipe. While similar in concept, its structure and its application range vastly differs from the present invention.
U.S. Published Patent Application No. 2011/0126933 to Bowie describes a pipe end-sealing tool that engages the outer wall of the pipe and provides a means to pressure test the integrity of the pipe. This device engages a pipe end with an external means, allowing a plug to be fitted therein. The intent and structure of the Bowie device, however, are substantially divergent from the present invention.
The present invention provides a novel means and method for engaging a pipe end with a plug and simultaneously providing an outgoing route for flowing fluid therethrough. A saddle is attached to the exterior of the pipe below the pipe end, and is used as a ground support to winch a platform into place over the leaking pipe end. A tapered, apertured plug seals the plug and provides an auxiliary pipe for which to divert exiting fluid. Support bars establish a safeguard for the winching means, preventing the platform from dislodging therefrom under pressure load from existing pipe end fluid. They further allow adjustment of the plug position to ensure the plug properly seats into the pipe end. Prior to engagement, the aperture in the plug provides a path for exiting fluid to reduce pressure on the platform as it is lowered into place. The devices in the prior art fail to address the needs satisfied by the present invention. Further, its structure substantially diverges in design elements from the prior art. Consequently it is clear that there is a need in the art for an improvement to existing pipe end plug devices. In this regard the instant invention substantially fulfills these needs.


A slot-type gaming machine using an expandable symbol array to create a series of sequentially larger symbol arrays with the potential for additional or enhanced awards. The generation of the larger arrays can be performed through a variety a different mechanisms, such as the addition of a reel to the base array. The secondary arrays may be generated only under specific sets of circumstances that occur in the base array including, a winning pay line, the occurrence of a bonus triggering symbol, etc. To increase player interest in the game, some embodiments include allowing the player to determine where the additional symbols to create the larger array are placed in the base array.

Gaming machines, such as slot machines, video poker machines and the like, are the cornerstone of the gaming industry. The commercial success of these gaming machines is as dependent on their entertainment value as their likelihood of providing a winning payout. To improve the entertainment value of their products, manufacturers have developed a variety of enhancements to the basic slot-type game. For example, gaming machine manufacturers have embellished their gaming machines with bonus games.
Bonus games typically start when a predetermined base game outcome occurs. Bonus games provide additional play features that embellish the play of the basic slot game. For example, some base games may trigger wild symbols that form additional winning pay lines. Still another bonus feature adds a surprise pay line to the array to provide players with another way of winning the game. All these features are designed to give the player a more entertaining gaming experience.
Although these bonus games and features have had varying degrees of success, players are always looking for new games and with new features. In the competitive gaming industry, there is a continuing need for slot machine manufacturers to produce new types of games that will attract players.


Provided is a security checking system. The security checking system includes an electron beam acceleration unit for accelerating electron beams having at least one energy intensity, an X-ray guide unit converting the electron beams accelerated by the electron beam acceleration unit into X-rays to guide the converted X-rays into an object, a neutron guide unit, and a detection unit detecting the X-rays and neutrons passing through the object. Thus, nuclear materials within the object may be detected, and also, maintenance/repair costs may be inexpensive to improve economic feasibility.

In facilities handling international cargo, such as harbors and airports, are reinforcing security check in regard to cargo for the purpose of safety. Recently, in developed countries, for example U.S.A., inspection for not only explosives but also special nuclear materials is being requested in advance.
Generally, X-ray inspection is used for the inspection for explosives and nuclear materials. However, the X-ray inspection method is technically limited. Accordingly, an inspection method using a neutron source is being raised as a method for detecting the nuclear materials, U 235 and Pu-239, included in the cargo.
As a neutron source for detecting the nuclear materials, a Cf-252 isotope is generally used due to its convenience in use. However, a half-life of Cf-252 isotope is approximately 2.8 years, that is, a neutron production rate reduces so fast that the neutron generation rate may reduce to almost 1/10 or less after about eight years of use. In addition, handling of the Cf-252 isotope is not easy because a dedicated container is necessary when storing or transporting the Cf-252 isotope. Accordingly, when the nuclear material inspection method using the Cf-252 isotope is used, a charge cost of the Cf-252 isotope may be increased year after year due to the short half-life. In addition, a neutron generator is relatively uneconomical since an initial equipment of the neutron generator is expensive.

Security checking system using X-rays and neutrons


An image sensor includes an array of pixels arranged in rows and columns. A reference current source provides the reference current to a transistor forming one half of a current mirror. Each column has a current source, which forms the other half of a current mirror. A switch is provided to selectively connect a resistance between ground and the transistor. When the resistance is connected, the transistor is starved of gate-source voltage, which reduces the current supplied by each current source.

Image sensors traditionally are made up of an array of light sensitive pixels. The image sensor reads-out the value of each pixel to produce an image, and before the array of pixels is exposed to receive light, each pixel is reset.
As shown in prior art FIG. 1, a current column source ICOL is provided for each column to bias the pixels PIX of that column and, as such, reset their values. Each column current source ICOL is one half of a current mirror circuit. A diode connected transistor MBIAS makes up the other half of the current mirror and is common to each column current source ICOL. The current ICOLBIAS is mirrored at ICOL<1> to ICOL<col>.
The current column source ICOL is not required continuously during an imaging cycle, but only when the pixel values require to be reset for integration and readout. Consequently, to reduce power consumption, the circuit comprises two reference currents in parallel I1 and I2. A switch SW is provided for selectively connecting the reference current I2. When the current sources are required, the switch is closed and ICOLBIAS is equal to I1+I2. When the current sources are not required, the switch SW is opened and ICOLBIAS is equal to I1.
When switching between values of ICOLBIAS, there is an inherent lag associated with powering up and down of the array due to the associated parasitic capacitance of the array. It may take 5 μs or longer to switch between values of ICOLBIAS. As pixel arrays get larger, the parasitic capacitance increases and the time to switch between values of ICOLBIAS increases further.