A system and method for providing media streaming are provided. A media description file having a range string indicator is used to specify location offsets of a plurality of media fragments within a media file. The range string may be stored directly in the media description file or the media description file may contain an indicator specifying a file containing the range string. The media description file may also include a range unit specifying the size of the offsets in the range string. In an embodiment, offsets within the individual media fragments may also be provided, either in the media description file or in a different file.

Media streaming, such as streaming audio, video, images, text, and the like, is a popular use of the Internet. Generally, media streaming involves sending large amounts of data from a media server to a client device, such as a personal computer, a mobile device, a television, or the like. Each media stream may have many alternate media streams, such as audio alternatives for different languages, textual alternatives for closed captioning alternatives, etc. Furthermore, due to the large file size and differing network constraints of the client device, media alternatives for different bit rates may also be provided, thereby providing multiple bit rate switching for adaptive streaming. Such a technique allows the media server to provide and/or the client device to request the media fragments of the quality most suitable given the network constraints. For example, a client device connected via a broadband connection may access high quality media streams while a client device connected via a lower bandwidth connection may access lower quality media streams.
During adaptive streaming, the media stream is usually provided in chunks, or media fragments. For easy content management on the streaming media server side, storing all media fragments belonging to the same quality level audio/video alternative together as one file is one popular solution. In this solution, a text-based media description file contains separate descriptions with the time offsets of each media fragment contained in the single file, thereby allowing the use of standard HTTP servers. Including a separate text-based description for each media fragment for the media stream, however, may create a very large and unmanageable text file for media contents with reasonable durations and several video/audio (and/or other media types such as text or graphics) alternatives, which degrade the streaming performance, e.g. longer startup delay.
For example, considering one media content with 90 minutes duration, 7 video alternatives of different bit rates, 2 audio alternatives of different languages, and a media fragment size of 2 seconds each, then there are a total of (90 minutes×60 seconds/minute×7 video alternative×2 audio alternatives)/2 seconds/fragment, or 37,800 media fragments, each of which is individually textually defined in the media description file.

Combined binary string for signaling byte range of media fragments in adaptive streaming


A display screen component and an electronic device are provided. The display screen component includes a display screen and a sensor unit arranged at a side of the display screen. The display screen includes a display area and a non-display area. The sensor unit includes a signal emitter and a signal receiver, the signal emitter is arranged at a side of the non-display area, and the signal receiver is arranged at a side of the display area. The non-display area includes a functional portion, the signal emitter is configured to emit a detecting signal to outside through the functional portion and the signal receiver is configured to receive a reflected signal from the outside through the display screen, in which the detecting signal is changed into the reflected signal after being reflected by an external object.

With developments of communication technology, the electronic device (such as the smart phone) is more and more popular. In a process of using the electronic device, for example during a call, in order to avoid the user's misoperations of the electronic device, when the user's face approaches the electronic device to a certain distance, the display screen of the electronic device will go out automatically.
Generally, the electronic device detects the approach or departure of the user's face by the proximity sensor, and the display screen of the electronic device is controlled to go out or light up according to the detected data.

Display screen component and electronic device

GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD.


A side chain liquid crystal polymer and a manufacturing method therefor are provided. Also, an optical recording medium of which recording layer is made of the side chain liquid crystal of the present invention is provided. The side chain liquid crystal polymer expressed by the following formula (V) has excellent processing properties due to its high solubility. Also, due to its high glass transition temperature and low polydispersity, information recorded on a recording layer made of the polymer can be preserved for a long time. In addition, since the recorded type (pit) is even, the error rate is low and the occurrence of jitter noise can be remarkably reduced: ##STR1## where A is either CH.sub.2 or CH.sub.2 --O--(CH.sub.2).sub.m, R is either OCH.sub.3, CN or NO.sub.2, l is 10 to 100, m is 1 to 6, and n is to 20.

The present invention relates to a side chain liquid crystal polymer, a manufacturing method therefor and an optical recording medium employing the same, and more particularly, to a side chain liquid crystal polymer which is easy to be formed into a recording layer of an optical recording medium due to its excellent solubility, and when used for a recording layer of the optical recording medium, can store the recorded information for a long time, a manufacturing method therefor and an optical recording medium employing the same.
A worldwide information explosion has required high density and high capacity recording media as well as recording media capable of high speed recording. Therefore, a new recording method, using an optical recording medium, has been introduced.
However, according to the magneto-optic recording method, the magnetization direction is orthogonal to the surface of a recording layer, and thus it is difficult to change the magnetization direction, in contrast to using a magnetic substance for a magnetic recording medium. Generally, the magnetization direction is changed by an external magnetic field while the recording layer of the optical recording medium is heated to the curie temperature or more by focusing laser beams to a spot size of 1 .mu.m, Also, the information is recorded according to the changed magnetization direction.
In the magneto-optic recording method, an information recording unit is small, at a level of 1 .mu.m or less, so that the recording density can be increased by 10.about.1,000 times that of the magnetic recording method. Also, since the recording and playback are performed in a non-contact manner, it is easy to store information and the life time is also increased.
However, such optical recording media has a recording layer which is formed of a heavy metal, and is manufactured by a complicated process such as sputtering or vacuum deposition. To solve these problems, research into the development of an organic optical recording medium has been conducted.
The organic optical recording medium is classified as one of two according to being erasable or not: a write once read many (WORM) type which allows only reading after writing once and a rewritable (RW) type which is erasable after writing.
The WORM type is manufactured by the steps of: forming a recording layer by coating a mixture of dyes for absorbing laser beams on a substrate, and forming a reflective layer and a protective layer on the formed recording layer. If the laser beams are irradiated on the recording layer of such recording medium, the dye of the recording layer absorbs the laser beam to generate heat, and the dye is then decomposed by the generated heat to form a pit. As a result, the recording is made. Meanwhile, the playback of the information is performed based on the difference of reflectivity between a portion with pits and another portion without pits.
For manufacturing the RW type optical recording medium, there is a method using a thermoplastic resin and a dye for absorbing near infra-red rays, and a method using a polymer blend. However, according to these methods, a recording sensitivity and a recording/erasing repeatability are both poor.
FIG. 1 shows a layer structure of a organic optical recording medium of RW type. The optical recording medium of FIG. 1 includes a substrate 1, a conductive layer 2, a recording layer 3, a reflective layer 4 and a protective layer 5.
Among those, the recording layer has a side chain liquid crystal polymer as a major component. The side chain liquid crystal polymer is roughly composed of a main chain, a spacer and a mesogen group, and provides the fluidity of a liquid and the optical anisotropy of a solid crystal. The optical recording medium adopting such side chain LCP records information by the following methods.
First, there is a method using a difference of optical characteristics such as transmittance and absorbency, which are determined according to the difference in alignment of the mesogen groups before and after the heating (recording) by the laser beams. In an optical recording medium adopting this method, the liquid crystals are aligned according to the applied electric field or magnetic field, or thermal treatment.
Second, there is a method using a difference of absorption spectrum which changes according to the interaction between the mesogen group and a chromophore before and after the heating (recording) by the laser beams.
In order to use the liquid crystal in a recording medium, there are required a high contrast between before and after recording, a long storage time, and easy of application to a substrate. However, the conventional liquid crystal polymers for an optical recording medium are inadequate in meeting one or more of the above requirements.
U.S. Pat. Nos. 4,904,066 and 5,259,987 disclose an optical recording medium using a liquid crystal polymer expressed by the following formula (I). The liquid crystal polymer can be dissolved in a general organic solvent, and thus easily spin coated on the substrate to form a recording layer. However, the glass transition temperature of the polymer is 25.degree. C. or less, so that the alignment of the liquid crystals is easily changed, resulting in inferior information storing property, even though the information is easily recorded. ##STR2##
U.S. Pat. No. 5,339,306 discloses an optical recording medium using a main chain polyester liquid crystal polymer and a main chain acrylate liquid crystal polymer, which are expressed by the following formulae (II) and (III), respectively. The main chain liquid crystal polymer dissolves only in a limited kind of an organic solvent such as trichlorobenzene or o-chlorophenol, so the coating property is not good. Also, the side chain acrylate liquid crystal polymer has a good solubility, but a glass transition temperature thereof is 50.degree. C. or less, so that it is difficult to store the recorded information for a long time. ##STR3##
U.S. Pat. Nos. 5,212,027 and 5,187,248 disclose an optical recording media capable of repetitive recording and erasing, which use an acrylate ferroelectric smectic liquid crystal polymer expressed by the following formula (IV). However, the glass transition temperature of the polymer is low, so the information storing property is inferior. ##STR4##
U.S. Pat. No. 5,019,476 discloses an optical recording medium using a side chain polypeptide liquid crystal polymer. However, this polymer dissolves only in a limited kind of an organic solvent such as chloroform and dichloroethane, so that the polymer can be coated only on an epoxy resin or a glass substrate. That is, it is impossible to apply the polymer to a polycarbonate substrate which has been widely used for an optical disk.

Side chain liquid crystal polymer, manufacturing method therefor and optical recording medium employing the same


This invention relates to Thypin, a new member of the human serpin polypeptide family, methods of making Thypin polypeptides and using these polypeptides to treat various medical disorders and to methods of screening for compounds that agonize or antagonize Thypin polypeptide activities.

"Serpin" is a name given to members of a group of single-chain 40–60 kDa proteins many of which are serine protease inhibitors, an activity from which the family originally derived its name (for reviews, see for example, Bird, Results Probl Cell Differ 24:63–89 (1998); Pemberton, Cancer J 10(1):1–11 (1997); Worrall et al., Biochem Soc Trans 27(4):746–50 (1999); and Irving et al., Genome Res 10:1845–64 (2000)). Serpins are conserved at the primary amino acid sequence level and also in their tertiary structure. Serpin family members generally share about 15–50% amino acid sequence identity. Three-dimensional computer generated models of the serpins are virtually superimposable. Serpins are found in vertebrates and animal viruses, plants and insects, and identified members of this superfamily number nearly 300.
Serpins may localize to the intracellular or extracellular space, the latter being mediated by a classical N-terminal signal sequence. A subset of the serpin family, the ovalbumin-like serpins (or "ov-serpins"), have a non-cleavable facultative signal sequence found near the N-terminus (Remold-O'Donnell, FEBS Letters 315:105–108 (1993)). Ov-serpins that possess this non-canonical signal sequence can demonstrate dual localization inside and outside the cell and are suspected to inhibit different intracellular and extracellular proteases. An example of a serpin with dual localization is PAI-2. Regulation of this dual localization may result in elevated plasma levels associated with various pathologies, such as SCCA in squamous cell carcinoma (Pemberton, 1997).
Serine proteases, which provide the targets for many of the inhibitory serpins, are involved in, and regulate, many aspects of biology including: degradation of extracellular matrix (such as elastases), vascular hemostasis (such as thrombin in coagulation, plasmin in thrombolysis), complement activation (such as complement factors), vasodilation in inflammation and hypertension (such as kallikreins), and digestion (such as trypsin). Leukocytes produce and store in vesicles many different serine proteases involved in cytotoxic responses (e.g. granzymes, chymases). Serpins also play a role in cell migration.
Serpin family members participate in variety of intracellular and extracellular processes, including serving as chaperones for protein folding, storage proteins, and transporting hormones. Inhibitory serpins participate in many important biological activities, including: complement activation; fibrinolysis; coagulation; cellular differentiation; tumor suppression; and selection processes associated with tumor survival (i.e., apoptosis and cell migration). Mutations in serpins may cause a number of diseases, some of which are associated with serpin polymerization (Irving et al, 2000). Such diseases include, for example, blood clotting disorders, emphysema, cirrhosis and dementia.
Many serpins are found at relatively high levels in human plasma. Plasma serpins are variably glycosylated, though this glycosylation may not be required for activity (Potempa et al., J Biol Chem 269:15957 (1994)). These include α1 antitrypsin (α1AT), which is involved in restructuring of connective tissue; C1 inhibitor, which controls complement activation; plasminogen activator inhibitors 1 and 2 (PAI-1 and PAI-2), which help control fibrinolysis; and antithrombin, which is involved in regulating the coagulation cascade. Also present in blood are angiotensinogen, which when cleaved gives rise to vasopressor peptide that helps control blood pressure, as well as thyroxine binding globulin (TBG) and the corticosteroid binding globulin (CBG). Proteolytic cleavage of TBG appears to provide a mechanism for site-specific release of thyroxine (Schussler, Thyroid 10(2):141–49 (2000)). The serpins maspin, PAI-2 and α1AT, under certain circumstances are capable of polymerizing (Pemberton, 1997). Some serpins, such as AT-III, achieve a much higher level of inhibitory activity if activated by polysulfated oligosaccharides such as heparin (Potempa et al., 1994). Other serpins shown to bind heparin cofactor II include protease nexin-1, active protein C inhibitor and PAI-1 (Potempa et al., 1994).
The ov-serpins are characterized by their relatively high degree of homology with chicken ovalbumin. The ov-serpins are reviewed, for example, in Worrall et al., 1999 and in Remold-O'Donnell, 1993. Ov-serpins generally have eight exons, seven introns and highly conserved intron-exon boundaries, though the ov-serpin PI-6 has only seven exons and six introns. The ov-serpins typically lack the extended N-terminal and C-terminal regions found in other serpins. Moreover, they possess an internal hydrophobic sequence near the amino terminus that allows both secretion and intracellular retention, depending on the cell type or the state of differentiation of the cell in which the protein is expressed. Ov-serpins have a higher degree of amino acid homology with one another than with the other serpins (e.g., they are 40% to 50% homologous with each other, but only about 30% homologous with the other serpins). In addition, ov-serpins have a penultimate serine at the C-terminus, and they have nearly identical splice-junction positions. The ov-serpins are predominantly intracellular, though some are secreted as well as being found intracellularly (e.g., maspin and PAI-2).
Other physiological processes in which serpins have been implicated include prevention of tumor invasiveness (maspin), storage (ovalbumin) and functioning as a chaperone in protein folding (HSP47) (see, for example, Whisstock et al., Trends Biochem Sci 23(2):63–67 (1998); Sauk et al., Connective Tissue Res 37 (1–2): 105–119 (1998)). The heat shock protein HSP47, although studied primarily for its role in collagen processing, sometimes escapes from the endoplasmic reticulum and reaches the cell surface, thus prompting Sauk et al. to propose that it could modulate cell migration during development and/or metastatic invasion of cancer cells (Sauk et al., 1998).
The clinical manifestations of serpin dysfunction include emphysema and cirrhosis (whisstock et al., 1998; Bird, 1998), which are associated with deficiencies in α1-proteinase inhibitor (also called "α1-antitrypsin"), which ordinarily control alveolar damage by neutrophil elastase. Accumulation of α1-proteinase inhibitor mutants in liver can give ruse to hepatitis or cirrhosis (Bird, 1998). Defective antithrombin III may underlie recurrent thromboembolic disease, and certain bleeding disorders could be related to deficient α2-antiplasmin activity, which results in higher levels of active plasmin thus increased fibrinolysis, while other clinical manifestations of serpin dysfunction include thrombosis, associated with antithrombin, which targets thrombin thereby inhibiting the coagulation cascade (Bird, 1998). It has been noted also that mutations in antithrombin III and α2-antiplasmin are associated with uncontrolled coagulopathies, and that hereditary angioneurotic edema is associated with deficiencies in C1-inhibitor, which targets C1-elastase and is an enzyme involved in the complement cascade (Potempa et al., 1998; Whisstock, 1998).
It has been noted that many aspects of osteoarthritis and rheumatoid arthritis involve cell invasion, that is, the ability of cells to cross anatomical barriers separating tissue compartments, and that proteases such as plasminogen activators and the matrix metalloproteinases play a role in controlling the activity of invading and proliferating cells in inflamed joints (Del Rosso et al., Clin Exp Rheumatol 17:485–98 (1999)). Del Rosso et al. summarize evidence that urokinase plasminogen activator (uPA) plays a key role in extracellular matrix destruction and formation of lesions in arthritic joints. They suggest that pharmacologically controlling the plasminogen activating system may be a viable approach to preventing the development of bone lesions and joint ankylosis in arthritis.
The serpin family also includes viral proteins that play a role in viral virulence. For example the cowpox cytokine response modifier gene (CrmA) can block apoptosis induced by a variety of stimuli, and is known to inhibit several of the interleukin-1β converting enzymes (ICE-like cysteine proteases). CrmA is considered a virulence factor for the cowpox virus. SERP1 (myxoma virus) targets uPA, tissue plasminogen activator (tPA) and plasmin, and promotes myxoma virus virulence.
The ov-serpins appear to be clustered within a 500 kb region telomeric to BCL2 at 18q21.3 (Silverman et al., Tumor Biol 19:480–87 (1998)). The two SCCA genes are less than 10 kb apart in this region and are flanked by the genes encoding PAI-2 and maspin (also called SERPINB5 or PI5). Additional serpins mapping to 18q21.3 are the cytoplasmic antiproteinase 2 (CAP2, also called PI8), bone marrow-associated serpin (bomapin, also called PI10 or serpin B10), hurpin (also called SERPINB13 OR "headpin") and megsin. The order of several of these serpins is cen-maspin, hurpin, SCCA-2, SCCA-1, megsin, PAI-2, bomapin and CAP2-tel. The SCCA-2 coding region has been cloned, and is disclosed in WO 9714425. Contigs containing this gene cluster can be found at the NCBI website using the nucleotide search and entering one of the following contig numbers: AC019355; AP001404; or AC015536. Chromosome 18q is known to be associated with breakpoints and loss of heterozygosity in cancers of the head and neck and other malignancies, thus suggesting that intact functioning of the serpin genes within this cluster may be disadvantageous to tumor growth (Spring et al., Biochem Biophys Res Comm 264:299–304 (1999)).
Some of the serpins have no discernable protease inhibitory activity, while others have been shown to inhibit serine or cysteine proteases (see, for example, Pemberton, 1997). Most of the ov-serpins inhibit serine proteases, however, SCCA-1, for example, inhibits cysteine proteases such as papain, cathepsins L, S and K, while the closely related SCCA-2 (92% amino acid sequence identity) inhibits chymotrypsin-like serine proteases such as mast cell chymase and cathepsin G. SCCA-1 is found mainly inside of cells, while the more acidic SCCA-2 is largely expressed in squamous cell carcinoma and released outside the cells (Suminami et al., Tumor Biol 19:488–93 (1998)). The cowpox CrmA protein also is a cysteine proteinase inhibitor. Hurpin is predicted to be an inhibitory serpin based on its hinge region homology with other serpins that possess this type of activity (Spring et al., (1999).
The basic scaffold possessed by all serpins usually includes nine a helices and three β-pleated sheets. Serpins that inhibit proteinases do so via a reactive site loop or "RSL" of about 20 to 30 amino acids located 30 to 40 amino acids from the carboxy terminus. The RSL is exposed on the surface of the protein and is susceptible to cleavage by non-target proteases (see, for example, Potempa et al., 1994). The core structure of the serpin molecule folds into a three-β-sheet pear shape that presents the RSL at the top of the structure. The RSL contains "bait" sequences that are believed to mimic the target proteinase's substrate. The inhibitory serpins regulate the activity of specific serine proteases by mimicking the protease's substrate and covalently binding to the protease when cleaved at the RSL. Upon cleavage by the target protease, inhibitory serpins undergo a dramatic conformational change, called the "stressed-to-relaxed" transition, which is accompanied by the insertion of the remaining reactive site loop into one of the β sheets. During this transition, serpins form a stable heat-resistant complex with the target protease. The sequence of the RSL, and particular the P1 and adjacent amino acid residues, determine an inhibitory serpin's specificity for a protease. An RSL is considered a key feature of serpin family members, and this structure is presented in the exposed surface loop at the top of the protein even in serpins that are not known to inhibit any proteinases.
Serpins with inhibitory activity possess several regions important in controlling and modulating serpin conformational changes associated with attaching to a target protease. As summarized in Irving et al. (2000), these are the hinge region (the P15–P9 portion of the RSL); the breach (located at top of the A β-sheet, the point of initial insertion of the RSL into the A β-sheet); the shutter (at top of the A β-sheet, the point of initial insertion of the RSL into the A β-sheet); and the gate (including strands s3C and s4C; to insert into the A β-sheet, the RSL must pass around the β-turn linking strands s3C and s4C). Inhibitory serpins possess a high degree of conservation at many key amino acid residues located in the above regions which that are believed to be necessary for enabling the protein to undergo the stressed to relaxed transition (see, for example, Table 2 in Irving et al., 2000).
Serpins lacking protease inhibitory function may exploit their "bait" sequences to attract a proteinase that cleaves within the bait sequence to activate a biological effector. Leukocyte elastase inhibitor (LEI), for example, appears to be converted by the serine protease elastase into a deoxyribonuclease that functions to degrade DNA during apoptosis (discussed in WO 99/58560). Another serpin, thyroxine binding globulin, is proteolytically cleaved to release biologically active T4 at specific locations in the body (Schussler, 2000) and angiotensinogen present in serum is cleaved by its target proteinase to generate the biologically active angiotensin protein. Similarly, corticosteroid binding protein is cleaved by the elastase at inflammatory sites to locally release corticol (Schussler, 2000).
The serpins PAI-1 and PAI-2 are involved in regulating the proteolytic breakdown of the extracellular matrix. Additionally, experiments have shown that PAI-2 protects cells against apoptosis induced by TNFα, apparently by blocking a protease, though PAI-2 does not protect against other apoptotic signals (for review, see Bird, 1998). PAI-2 also has been shown to bind to the anti-inflammatory and growth regulatory lipocortins (annexins). PAI-2 thus may be involved in regulating inflammation or growth factor signaling.
Proteinase inhibitor-9 (PI-9) is an ov-serpin proposed to protect cytotoxic T lymphocytes and natural killer cells from self-induced apoptosis resulting from exposure to granzyme B, an enzyme these lymphocytes produce to induce DNA degradation in target cells (Bird, 1998). PI-9 is not secreted and is apparently restricted to lymphoid tissue. Another inhibitory serpin, protease nexin I (PN-1) is secreted and is a potent heparin-dependent thrombin and urokinase inhibitor (Bird, 1998). It is proposed that PN-1 balances the action of thrombin on neuronal cells, thereby rescuing neural cells from apoptosis that otherwise would be induced by the action of thrombin on receptors on the surface of the neurons (Bird, 1998).
Serpins were originally shown to be involved in suppressing tumor invasion by directly inhibiting the matrix-degrading serine proteases uPA and plasmin produced by some tumor cells. Tumor-produced proteases are believed to facilitate a tumor's ability to metastasize, thus are targets for therapeutic intervention. Some cysteine proteases, such as the calpains, have been implicated in apoptotic pathways involved in tumor surveillance (Pemberton, 1997).
One serpin with demonstrated tumor-suppressing capacity is the ov-serpin maspin. Maspin is found mainly in the membrane fraction of epithelial cells (such as breast and prostate), and its expression is downregulated in mammary tumor epithelium (reviewed in Sager et al., in "Chemistry and Biology of Serpins," eds. Church et al., Plenum Press, NY, 1997, at pages 77–88). Although maspin has been shown to suppress the invasiveness of both breast and prostate tumor cells, it does not appear to inhibit any proteases. Even so, if trypsin is used to cleave the maspin RSL, maspin loses its ability to inhibit tumors. Evidently, maspin interferes with tumor growth by some as-yet-unidentified mechanism that requires an intact RSL.
In some cancers, elevated plasma levels of certain serpins serve as markers of cancer progression. For example, the level of the prostate specific antigen (PSA) in complex with α1AT is used to monitor the progression of prostate cancer (Pemberton, 1997). Another serpin used as a tumor marker for prostate cancer is prostapin, which is described in WO 99/58560. The ov-serpins SCCA-1 and SCCA-2 in fact were originally identified as squamous cell carcinoma antigens, and a monoclonal antibody with which both SCCA's react is commonly used to monitor progression of this type of tumor (Barnes et al., Gynecol Oncol 78:62–66 (2000)). The SCCAs are elevated in squamous cell carcinomas of cervix, lung and esophagus, and SCCA levels are used as a serological marker for the extent of disease in advanced cases of these tumors (Silverman et al., 1998; Barnes et al., 2000). Suminami et al. (1998) report that the SCCA produced in epithelial cancers is primarily SCCA-2, and propose that SCCA-2 normally protects epithelial cells from inflammation. Elevated serum levels of SCCA have also been observed in patients with benign skin disorders with an inflammatory component. Such conditions include psoriasis and eczema (Barnes et al., 2000). SCCA-1 and SCCA-2 are elevated in psoriatic epidermis and are disclosed as psoriasis markers called "psoriastatin 1" and "psoriastatin 2" (WO 97/14425). Another related serpin, hurpin, also is overexpressed in psoriatic skin lesions and is disclosed as a lung tumor antigen (WO 99/47674). Hurpin is expressed in normal oral mucosal tissue, skin and in cultured keratinocytes, but is underexpressed in squamous cell cancers of the oral cavity (Spring et al., 1999). Bomapin is expressed specifically in the bone marrow (Riewald and Schleef, J Biol Chem 270:26754–57 (1995)).
Various serpins are expressed by many tissues in the body (see, for example, Worrall et al., 1999). Those present at high concentrations in the blood generally are synthesized in the liver. PAI-2 and LEI, for example, are expressed in monocytes. Maspin is expressed in normal mammary epithelium (Sager et al., 1997). SCCA-1 and SCCA-2 are expressed in normal and malignant squamous epithelium, particularly in the spinous and granular layers of epidermis and in the intermediate layer of the ectocervical epithelium (Suminami et al., 1998).
In order to develop more effective treatments for conditions and diseases mediated by serpins and their targets, more information is needed about unidentified members of the serpin polypeptide family.


A process and apparatus for forming a hardened outer shell (40) on a refractory metal workpiece (36) preferably heated in a fluidized bed of metallic oxide particles (38) in an environment of an inert gas and a reactive gas with the reactive gas either oxygen or nitrogen. The workpieces (36) are heated in the fluidized bed to a temperature between 800 F. and 1600 F. for a period of over two hours to form hardened outer shell (40) in two layers (42, 44). Outer layer (42) is an oxide or nitride layer having a thickness (T1) between 10 microns and 25 microns. Inner layer (44) is a case hardened layer of the refractory metal having a thickness (T2) between 25 microns and 75 microns. In one embodiment workpieces (56) may be cold worked by peening from finely divided metal oxide particles (54) to provide a uniform surface texture for subsequent hardening.

This invention relates to a process and apparatus for the surface hardening of workpieces made from refractory metals or metal alloys containing refractory metals and particularly such a process and apparatus for workpieces made from such refractory metal or alloys and utilized as bearings, valves, or similar products which are subjected to wear or abrasion.
A group of metals known as refractory metals consisting of zirconium, tantalum, titanium, hafnium, niobium and some others, have a common characteristic in that oxygen and nitrogen can penetrate and/or react with the surface of the metal to form a hardened case a few thousandths of an inch thick, and simultaneously build barrier compounds of oxides or nitrides on the surface, which prevent or limit further penetration. The characteristic is also observed with alloys of metals wherein at least the major metal portion is a refractory metal. The oxides and nitrides which form on the surface are extremely hard and wear resistant, but are very thin. The deeper or thicker cases which form beneath the surface are sometimes less hard, but have much greater depth, are less brittle, as they are made up of alloys of the base metal with oxygen or nitrogen rather than oxides or nitrides thereof. Oxides which form on the surface of these metals are known as ceramics and are very dense, hard and abrasion resistant. Nitrides which form are also separate compounds and are extremely hard and abrasion resistant. By appropriate combinations of temperature, atmospheres and other hardening techniques, it is possible to form combinations of hard surface compounds and alloyed sub surface cases which have very desirable properties.
Zirconium has long been recognized as a highly corrosion resistant material for severe applications. However, zirconium is relatively soft, about 65 Rockwell B, and is easily marred or damaged. It has not heretofore been suitable for heavy dynamic contact such as metal seals and wear parts. A number of previous studies indicated that zirconium could be case hardened by oxidizing the surface at temperatures about 1000 F. With careful control in a laboratory environment, a ceramic zirconium oxide surface nearly one (1) mil thick can be formed. Further, zirconium metal beneath the oxide surface can be hardened by alloying with oxygen.
However, there is a critical time and temperature relationship for hardening zirconium by oxidizing in order to obtain the desired hard and dense film. If heated for too long a period of time at a relatively high temperature, the zirconium alloy workpiece may be seriously damaged. Under isothermal heating, the rate of hardening as measured by oxygen pickup will decrease with time. During this period of decreasing rate of oxygen pickup, a dense, tough, tightly adhering, blue-black case will form without any effect on the surface finish, and without any significant distortion of the part. However, continued heating will result in a fairly sudden increase in oxidation rate, and a case which is less abrasion resistant, brittle, and rough-surfaced will form. In addition, significant dimensional changes may take place.
The borderline between the conditions which form desirable cases and those which are over-oxidized is critical, and the results of excess oxidation are severe, so production practice has been very conservative using relatively low temperatures and accepting cases much less than optimum. Such cases are suitable for most uses and do provide a degree of resistance against marring, but they are substantially less than theoretically possible, and are not suitable for heavy sliding contact or abrasive wear for prolonged periods of time.
As indicated, zirconium has superior corrosion resistance properties and is utilized extensively in the chemical processing industry particularly where high operating temperatures and/or pressures are involved in an aqueous media. However, zirconium has a relatively low resistance to abrasion and in order to increase its resistance to abrasion and resulting wear, it is necessary to harden the wear surfaces. Heretofore, such as shown in U.S. Pat. No. 4,671,824 dated Jun. 9, 1987, a process is disclosed for a hardened wear surface from providing a zirconium alloy surface by treating the zirconium alloy in a heated molten salt bath containing small amounts of sodium carbonate which is an oxygen bearing compound. The thickness of the blue-black coating formed by this process by oxidation of the zirconium alloy was not specified but was defined as a relatively thin coating.
A fluidizing bed for forming a hardened layer on a workpiece has been utilized heretofore for certain workpieces such as illustrated in U.S. Pat. Nos. 4,141,759; 4,547,228; and 4,923,400 for example. An inert gas and various metal treatment processes such as nitriding or oxidizing have also been utilized with a fluidized bed as shown in these references. However, the use of a fluidized bed for refractory metal workpieces, which naturally form barrier compounds to the infusion of reactive gases and particularly a fluidized bed of oxide materials having an affinity for the reactive gas, or metal oxide wherein the metal has an affinity for oxygen, at least as great as the refractory workpieces has not been shown by the prior art.
The hardening of reactive metals has been accomplished in a number of ways heretofore. However, such hardening operations have been characterized by the formation of a hard chemical compound of the workpiece metal and the reactive gas on the outer surface, without the benefit of deeper harder surfaces as the chemical reaction on the outer surface prevents or limits diffusion of the reactive ions for creating the deeper alloy case.

Apparatus for surface hardening of refractory metal workpieces


A device is described for indicating the locking state of a fifth wheel coupling and an arrangement of a first and a second sensor. According to the prior art, the first sensor is arranged on the underside of the locking latch and monitors the position of the kingpin in relation to the locking latch. A second sensor that is used is an inductive proximity switch that monitors a safety mechanism against loosening. In practice, this type of positioning of the first sensor has led to damage of the locking latch and the first sensor, while the signals of the second sensor were often false signals. Thus, the object of the invention is to provide a device for indicating the locking state, which maximizes operational availability and minimizes false signals. A further object of the invention is to optimize the arrangement of the first and the second sensor. These objects are attained by arranging the first sensor detecting the kingpin in the area of the locating hole and configuring the second sensor as a magnetically sensitive sensor that interacts with a magnet mounted on the operating lever. The two sensors are based on different mechanisms of action.

DE 198 20 139 A1 represents a generic prior art in this connection. This document describes a method and an arrangement for monitoring the proper locking and securing of a fifth wheel equipped with a locking mechanism and a safety mechanism. A first sensor is provided for monitoring the state of the locking mechanism and a second sensor for directly or indirectly monitoring the state of the safety mechanism. The first sensor is an inductive proximity switch and is intended to be mounted on the underside of the locking latch and to monitor the position of the kingpin in relation to the locking latch. If the kingpin is driven in too high, it rises above the locking latch, which increases the risk of false detections. In practice, however, such a positioning of the first sensor has proven to be a drawback because the locking latch must first be locked before the sensor can detect the position of the king pin in relation to the locking latch. An incorrect positioning of the kingpin led to increased wear and damage to the locking latch and the first sensor mounted thereon, since the locking latch, even during travel, is subject to substantial impact loading, which is also transmitted to the first sensor. Another weak point is the flexibly installed cables. The second sensor is likewise an inductive proximity switch, which monitors a locking mechanism that secures the safety mechanism against loosening. For this purpose, a tongue of the locking mechanism is monitored, which is within the detection range of the sensor only as long as the locking mechanism stays in a locked position in which the operating lever is secured by a cam. The essential drawback of the sensor arrangement of this second sensor is that there are frequent false alarms because the major part of the fifth wheel is made of steel, and actuating the operating lever changes the position of a plurality of other components in relation to the second sensor, which then trigger a false signal.

Device for indicating the locking state of a fifth wheel coupling and sensor arrangement


An improved method for depositing the polysilicon layer from which a gate pedestal is later formed is described. Deposition takes place in two stages. Initially, the conventional deposition temperature of about 630.degree. C. is used. Then, when the intended thickness of polysilicon has been grown, the temperature is ramped down to about 560.degree. C., without interrupting the deposition process, and growth of the film continues to completion. This is followed by a standard doping step using POCl.sub.3. Polysilicon films formed in this way have been found to have very smooth surfaces because the topmost layer is less subject to uncontrolled grain growth. As a consequence, dielectric layers obtained by oxidizing such films exhibit superior breakdown voltages.

In certain integrated circuits it is required to fabricate a capacitor in series with the gate. The latter is usually made of polysilicon and needs to be heavily doped with a donor material in order to reduce its resistivity. This is commonly achieved by using POCl.sub.3 (phosphorus oxychloride) as a diffusion source. Doping in this manner means subjecting the polysilicon gate pedestal to temperatures as high as 950.degree. C. for as long as 15 minutes.
In FIG. 1 we show a schematic view of a capacitor of this type. Source and drain regions 3 and 4 are formed within silicon body 2. Spanning the gap between 3 and 4 is a layer of gate oxide 5 above which is a heavily doped polysilicon pedestal that serves as the gate electrode. Dielectric layer 7 lies atop layer 6 and conductive layer 8 is the counter electrode for the capacitor structure that has thus been formed. Although shown here as a single layer, 7 is often a hybrid of more than one material. For example it could be composed of a layer of silicon oxide topped by a layer of silicon nitride. Regardless of what dielectric material is being used, if there are rough spots on upper surface 9 of poly gate 6, these will act as local high field points at which premature dielectric breakdown will occur.
Polysilicon is normally deposited by CVD (chemical vapor deposition) using silane as the silicon bearing gas. Deposition takes place at about 630.degree. C. Associated with this relatively high temperature is considerable grain growth. This is not, of itself, a problem but, as already mentioned above, the polysilicon gate pedestal still has to undergo POCl.sub.3 doping. During the latter procedure, grains of different crystal orientation react somewhat differently to the incoming phosphorus atoms. The net result is a surface that, on a microscale, is quite rough. This roughness (which we measure in Angstroms) is defined by using an AFM (Atomic Force Microscope).
As already noted above, if at least one surface of the capacitor's electrodes is rough, the breakdown voltage of the resulting structure will be lower than is achievable with the materials being used. For example, curve 21 of FIG. 2 is a plot of capacitor leakage current as a function of applied voltage across a capacitor whose lower polysilicon electrode was prepared as described above. The dielectric was 4400 Angstroms thick. Breakdown was defined to have ocurred when the leakage current reached 1 microamp. The breakdown voltage V.sub.B was 60 volts.
Prior art in this area appears to have been focussed on increasing the capacitance per unit area of the capacitors rather than on raising the breakdown voltage. Thus, Zahurak et al. (U.S. Pat. No. 5,639,685 June 1997) disclose a method for increasing the roughness of a polysilicon surface by depositing a thin layer of amorphous silicon onto it and then annealing between about 350.degree. and 600.degree. C. in the presence of a dopant bearing gas. This causes the amorphous silicon to crystallize into hemi-spherical grain polysilicon which leads to an increase in surface area which in turn means a larger capacitance per unit area when a dielectric layer and counter-electrode are deposited over it.
Hayashide et al. (U.S. Pat. No. 5,290,729 March 1994) is similar to Zahurak et al. in that its purpose is also to increase the effective surface area of a capacitor and they achieve this by depositing polysilicon under conditions close to the transition conditions from amorphous to polycrystalline. Lou et al. (U.S. Pat. No. 5,597,754 January 1997) is similar. Increased capacitance is achieved by forming a hemispherically grained surface of polysilicon for the lower electrode. Dennison et al. (U.S. Pat. No. 5,663,090 September 1997) also teach how hemispherical grain silicon may be used as a capacitor electrode.
Chou (U.S. Pat. No. 5,286,668 February 1994) describes a capacitor that is in series with the drain and is located alongside the gate pedestal. By shaping it so that the lower electrode extends upwards and outwards from the drain a capacitor that overhangs the gate is formed. Several different polysilicon layers are used as part of the process.

Process for forming a polysilicon layer having improved roughness after POCL3 doping

Taiwan Semiconductor Manufacturing Company, Ltd.


A chair system may include a plurality of components that may include a seating surface having seating handles, a backrest having a backrest handle, a kickstand base, and a support frame. The configuration may generally provide a lightweight, comfortable chair system that may be easily adjusted, lifted, transported, arranged and stacked by any user, while still providing substantial structural integrity.

Conventional chairs typically used in educational environments are bulky and generally fail to provide adequate leverage for all users, especially younger students, to easily adjust, lift, arrange and stack such units as is often necessary in a classroom. Moreover, conventional chairs generally comprise a back, a base, and a leg supporting each corner of the base.


A system that incorporates teachings of the subject disclosure may include, for example, a central controller that executes instructions facilitating performance of operations including monitoring multiple network nodes, at least some of the network nodes being in communication with others through respective point-to-point links. Each point-to-point link includes a respective free space optical channel. The central controller detects optical received signal strength of a free space optical channel falling below a certain level and provides control signals to reconfigure the multiple network nodes. Signals are re-routed along one of the respective point-to-point links through other network nodes responsive to detecting the optical received signal strength falling below the certain level Other embodiments are disclosed.

Free space optical channels link together plural distributed switching nodes into a network. A central controller commands these nodes over a known radio telephone system to select alternative network routes to a destination that will bypass adverse environment conditions.
It is an object of the present invention to provide a network with broadband performance even in the presence of adverse link conditions such as rain or fog. It is a further object of the present invention to provide 911 services and critical low speed data services in the presence of adverse link conditions.
These and other objects are achieved in a communication system that includes a plurality of nodes and a plurality of point-to-point links that interconnect the plurality of nodes into a network. Each node includes an optical switch to controllably route a plurality of in-ports of the optical switch into a plurality of out-ports of the optical switch. Each point-to-point link includes a free space optical channel. A first free space optical channel couples to a first node through a receive path and a through a transmit path. The receive path couples to a respective in-port of the optical switch of the first node, and the transmit path couples to a respective out-port of the optical switch of the first node.
These and other objects are achieved in an alternative embodiment of a communication hub that includes a plurality of neighborhood links to corresponding users, an optical switch coupled to the plurality of neighborhood links, and a trunk coupled between the optical switch and a free space optical channel link to the network.
These and other objects are achieved in a method of communicating in a network having plural links that includes sensing the presence of a received signal failure by monitoring channel losses in a first link, the received signal failure resulting from at least one of rain and fog. The method further includes sending data in a free space optical channel of the first link when the received signal failure is sensed due to rain and sending the data in an RF channel of the first link when the received signal failure is sensed due to fog.

This patent is subject to a terminal disclaimer.


According to one embodiment, a memory element includes: a first electrode layer; a second electrode layer; and a memory layer provided between the first electrode layer and the second electrode layer, and the memory layer including a plurality of first oxide layers in a second oxide layer, a resistivity of each of the plurality of first oxide layers being higher than a resistivity of the second oxide layer.

Resistance change memories that store data based on the resistance state are researched and developed. The resistance change memory includes a memory layer of which the resistance can change between a low resistance state and a high resistance state. Data storing can be assigned data to the low resistance state and the high resistance state. Here, the memory layer can be switched between the low resistance state and the high resistance state by applying a voltage to electrodes formed at its both ends.

Resistance change memory element and resistance change memory


Sound reflectors for an electronic device are provided. In one embodiment, the sound reflector has a sound redirecting surface having two curvatures. The first concave curvature is in one plane and the second curvature is in another plane, and the first and second curvature's planes are in obtuse angle with each other. In other embodiments, the sound reflector has a device attachment surface configured to attach to a back of the display device, which the sound reflector is coupled with, and a sound redirecting surface. The sound redirecting surface has a proximal portion that extends backwards relative to the device attachment surface, and a distal portion that extends forward relative to the attachment surface. The sound redirecting surface is disposed to directly receive sound emanating from the speaker.

The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
Many electronic devices including flat screen televisions and mobile devices have built-in speakers, and most of the built-in speakers for such electronic devices are down-firing speakers. However, because of their relatively smaller size and location in the back, bottom or side of the device, the speakers of such devices often cannot produce sound waves that transmit only indirectly to the user. Rather, sound waves are directed to objects nearby the electronic devices, and the sometimes tortuous reflected paths can produce decidedly deteriorated sound quality.
Some efforts have been made to improve the sound quality from the down-firing speakers. For example, U.S. Patent Application 2013/0303146A1 to Genoa discloses a sound enhancer coupleable to a portable media. The sound enhancer can redirect sound from a side-mounted or back-mounted speaker of the portable media player towards a user for enhancing the user's audio experience. However, the size of Genoa's sound enhancer is limited to the length or width of the speaker, and the use is therefore limited to many portable electronic devices.
Others have made efforts to enhance the sound emitted from device speakers. For example, U.S. Pat. No. 8,731,219 to Weiss discloses a reflector for use with an electronic device having a loudspeaker. The reflector of Weiss has a flat portion located to be adjacent a surface of the electronic device, and a concave portion adjacent to the flat portion and presenting a concave surface to the loudspeaker. However, similar to Genoa, the size of this reflector is also generally limited to a size of the speaker. Further, the direction of sound reflection cannot be adjusted based on the user's needs.
U.S. Pat. No. 6,257,365 to Hulsebus III discloses a speaker system that includes a cone reflector connected to a speaker driver. The cone reflector has at least one included angle used to reflect sound in a desired pattern in the horizontal and vertical planes. The reflecting surface can be flat, concave, or in combination of multiple angle flat surfaces. The reflector can be attached to the speaker, or can be free-standing. However, due to its cone-shape, the Hulsebus reflector is not suitable for use with many televisions, and in particular with flat screen TVs.
U.S. Patent Application 2012/0241247A1 to Choe discloses audio enhancer for very small devices, e.g., smart phones and smart tablets, where the reflector portion can be flat or curved. This audio enhancer can be attachable and detachable to an audio producing device.
U.S. Patent Application 2015/0131836A1 to Hoshikawa discloses a sound guiding device for an electronic device with a rear-facing speakers. In Hoshikawa, the sound guiding device is attached to a case of mobile terminal device such that a curved portion of the device receives sounds from the rear-facing speaker and redirects the sounds toward the front of the device.
Interestingly, none of the above discloses a sound reflector or a sound redirective device for flat screen TVs that properly accommodates different positioning of the speaker(s). Thus, there is still a need for a system that can effectively redirect the sound from the built-in speaker of a flat screen TV, regardless of the front to back location of the speaker(s).

Sound redirecting device for large displays


A waterproof connector includes a terminal, a housing, a seal member, an inclined guide portion and a slide contact portion. The housing includes an insertion opening provided for receiving the terminal, a terminal lock portion provided inside the housing and a fixing lock portion provided outside the housing, both used for locking the terminal. The inclined guide portion is provided on either the housing or the fixing portion of the seal member, and the slide contact portion is provided on the other of the housing and the fixing portion so as to be slidable relative to the inclined guide portion. The inclined guide portion and the slide contact portion guide the seal member so that it rotates into a proper position and so that the fixing engagement portion engages with the fixing lock portion when the seal member is inserted into the insertion opening of the housing.

1. Field of the Invention
The present invention relates to a connector having a waterproof structure.
2. Description of the Related Art
Conventionally, as the connector of this type, there has been proposed such a connector as shown, for example, in FIG(S). 5, 6(a) and 6(b) (Japanese Utility Model Unexamined Publication No. Hei. 4-101382).
In this connector, a terminal 5 with a cable 3 clamped therein is received in a housing 1. The terminal 5 is inserted into the housing 1 from its insertion opening 7. A flexible lance 9 is provided in the inside of the housing 1 as a terminal lock portion for locking the terminal 5. Therefore, the terminal 5 is engaged with the flexible lance 9 so as to be locked. Lock pawls 11 are provided, as fixing lock portions, so as to project from an outer surface of an end portion of the insertion opening 7 of the housing 1. The insertion opening 7 of the housing 1 is sealed with a seal member 13 formed of an elastic body such as rubber so as to be waterproofed. The seal member 13 is tightly fitted onto the cable 3 at the terminal 5 side of the cable 3, and a front end (in FIG. 6(a)) of the seal member 13 is fixedly clamped with the cable 3 in a cable clamping portion 15 of the terminal 5. An outer peripheral surface of the seal member 13, on the other hand, is tightly fitted onto an inner peripheral surface of the insertion opening 7. A reinforcing portion 19 of an inserting member 17 is inserted into the inside of the seal member 13 (in FIG. 6 (b)) to increase the rigidity of the seal member 13. In the foregoing configuration, the waterproof function of the seal member 13 and the insertion workability of the seal member 13 into the insertion opening 7 are made improved. Lock engagement portions 21 are provided on the insertion member 17 so as to engage with the lock pawls 11. Consequently, the seal member 13 is accurately positioned by the engagement of the lock engagement portions 21 with the lock pawls 11 to thereby further improve the waterproof function.
In such a structure, however, the position of engagement of the flexible lance 9 with the terminal 5 and the position of engagement of the lock engagement portions 21 with the lock pawls 11 are determined univocally, while the insertion member 17 is assembled in the seal member 13 in advance and the seal member 13 with the insertion member 17 is fixedly clamped together with the cable 3 in the cable clamping portion 15 as shown in FIG. 5. Accordingly, the lock engagement portions 21 should be accurately positioned (particularly, in the direction of rotation) when the seal member 13 is clamped by the cable clamping potion 15, and there is a possibility that the assembling work of the seal member 13 in the terminal 5 becomes troublesome.
Further, there is a possibility that the lock engagement portions 21 are displaced in the rotational direction with respect to the terminal 5 so that it becomes difficult to attach the terminal 5, if the seal member 13 is clamped in the cable clamping portion 15 without performing accurate positioning.

Waterproof connector with guide portion for aligning connector during engagement


A recording apparatus records an image by relatively moving a recording head with respect to a recording sheet. When a recording sheet is conveyed by rotating a LF roller in accordance with recording operation at the recording position during the recording of a current recording sheet, it is determined whether or not recording for a next recording sheet is necessary. In the case of that recording for the next recording medium is necessary, the next recording sheet is fed by rotating the feed roller for the amount corresponding to the conveyance distance by rotation of the LF roller, in synchronization with the conveyance of the current recording sheet by rotation of the LF roller.

Recently, in a recording apparatus such as an inkjet printer which is connected to a computer, higher printing speed is required as the speed of computer systems increases. Furthermore, to meet the demands for a larger amount of printing paper (recording medium), increasing the number of printing paper is realized by incorporating a paper feed cassette that accommodates a large numbers of papers in the recording apparatus. However, the use of paper feed cassette elongates the paper conveyance distance, ultimately increasing the paper feed time. To increase the recording processing speed of an inkjet printer, reduction of paper feed time is desired.
In a conventional recording apparatus, image data received from a host computer is analyzed, a command is transmitted to a mechanical controller based on the analysis, and the operation of the recording apparatus starts. In this case, a paper is first picked up from the paper feed cassette, and then the paper feed operation starts. When it is confirmed that the paper is conveyed to a recording position by the paper feed operation, a printing command is transmitted to the mechanical controller to perform recording operation. Upon completion of recording one line or one band, a paper advance command is transmitted to the controller to advance the paper for the length corresponding to the recorded portion. By repeating the above operation, image recording of the entire page is performed. After the recording operation ends, a paper discharge command is executed to discharge the recorded paper. After the paper discharge operation completes, the feed operation of the next printing sheet starts.
Recently, as the capacity of the paper feed device including a paper feed cassette enlarges, the paper conveyance distance between the start point of the paper feed operation and the recording position is elongated. For this reason, in the conventional paper feed control, it is impossible to achieve an effect of improved throughput and is difficult to realize increased recording speed (Japanese Patent Application Laid-Open No. 2000-159392).
To save the time required for paper feeding and to increase recording speed, a recording apparatus which starts feeding of a paper for the next recording operation from the paper feed cassette during the current recording operation has been developed. In this recording apparatus, the paper pickup operation (pickup a paper from a paper cassette and feed it to a recording position) and paper feed operation (paper feed of a paper being recorded and for discharge the recorded paper) paper are performed by the rotation of one motor. In a case where there are a plurality of paper feed means and the means are removable as an option, the paper pickup operation and paper feed operation may not be performed by the one motor.
In a recording apparatus capable of loading a large amount of papers, e.g., a laser beam printer, paper pickup operation for the next recording is performed during recording operation of the current paper. However, paper pickup operation is independent of the paper feed operation, and the paper feed operation is performed as a series of operation. This is because, in a large apparatus such as a laser beam printer, it is possible to construct the apparatus such that the paper pickup operation and paper feed operation are performed independently of each other. However, in a small apparatus such as an ink-jet recording apparatus, it is impossible from the aspect of cost to construct the apparatus to perform the paper pickup operation and the paper feed operation during recording operation.

Recording apparatus, and feed control method of recording medium in the apparatus


A method for generating and transmitting optimal cell (base station) identification codes in a W-CDMA mobile communication system is disclosed. In the present invention, the cell identification codes are generated using Hadamard code and bi-orthogonal code. To optimize performance in a soft handover mode, cell identification codes are generated based on at least one of Hadamard codes and bi-orthogonal codes and then effectively transmitted through an uplink channel. Also, considering dynamic allocation depending on the size of an active set, optimal SSDT cell identifier codes having a maximized minimum Hamming distance are generated and then effectively transmitted through the uplink channel.

1. Field of the Invention
The present invention relates to a third generation mobile communication, and more particularly, to a method for generating and transmitting an optimal cell (base station) identification code using Hadamard code and bi-orthogonal code in a W-CDMA mobile communication system.
2. Background of the Related Art
The Radio Access Network (RAN) standards of the Third Generation Partnership Project (3GPP) describes a Site Selection Diversity Transmit Power Control (SSDT). The SSDT, which is a selective macro diversity technique in a soft handover mode, allows a User Equipment (UE) to select one of cells in an active set called "Primary." In this instance, all other cells are classed as "Non-primary."
The main object of the SSDT is to transmit on the downlink from a primary cell, which reduces interference caused by multiple transmissions in a soft handover mode. A second object of the SSDT is to achieve fast site selection without intervention from networks such as UMTS Terrestrial Radio Access Network (UTRAN), thus maintaining an advantage of the soft handover. In order to select a primary cell, a temporary identification (ID) is assigned to every active cell having a transmission power level higher than a predetermined level, and the UE periodically informs a primary cell ID to other connected cells. In this instance, the UE receives, measures, an compares power levels of common pilots from the respective active cells to select the primary cell, which has the greatest pilot power. Thereafter, the UE cuts off powers from all other remaining cells which are non-primary cells.
Referring to FIG. 1, an ID code for the primary cell is transmitted to cells in the active set through a Feed-Back Indicator (FBI) field among fields of a control channel, such as an up-link Dedicated Physical Control Channel (DPCCH). Next, as can be known from FIG. 2, the FBI is transmitted by 1 or 2 bits in one slot. If the FBI is transmitted by 1 bit, one radio frame is transmitted by 15 bits, and if the FBI is transmitted by 2 bits, one radio frame is transmitted by 30 bits, because one radio frame is transmitted by 15 time slots. When an ID code is transmitted to a selected primary cell, the UE determines whether one bit is inserted or 2 bits are inserted in the FBI field per one slot before transmission.
For reference, in FIG. 1, k is related to a Spreading Factor (SF) in a dedicated physical channel, wherein the SF having a value from 256 to 4 is expressed as 256/2k. Also, the numbers of bits of fields per a slot on dedicated physical data channel and the dedicated physical control channel of uplink DPCH are defined as in the following Tables.
TABLE 1channelchannelnumberslotbitsymbolbitsbitsofformatraterateperperNdata#IkbpskspsSFframeslotbits01515256150101013030128300202026060646004040312012032120080804240240162400160160548048084800320320696096049600640640
TABLE 2No.No.No.No.slotofofofoffor-CHCHbitsbitsbitsbitsbitsbitsmatbitsymbolperperofofofof#IraterateSFframeslotNpilotNTFCINFBINTPC015152561501062021151525615010800221515256150105212315152561501070224151525615010602251515256150105221
The NFBI, representing a number of bits per slot inserted in the FBI field, is used in a closed loop mode transmit diversity or SSDT, which requires feed back between access points of the UE and the UTRAN. As shown in FIG. 2, the NFBI has an S field and a D field. The S field is used for processing a SSDT signal and the D field is used for processing a feed back mode transmission diversity signal. A length of the S field or D field may be 0, 1, 2. When both a power control by SSDT and a transmission diversity in feed back mode are used at the same time, the S field and the D field are required to each have one bit.
The operation of the SSDT for reducing interference caused by multiple transmission in the soft handover mode will next be explained in more detail.
In a soft handover mode, the SSDT is initially activated by UTRAN based on the cells in the active set, and thereafter the UTRAN of the SSDT option activated during a present soft handover period informs the cell and the UE. In this instance, a temporary ID is assigned to each active cell based on an order of the active set, and the assignment information on the IDs is given to the active cells and the UE. Thus, an active cell can identify its entry position in the active list, by which the ID code can also be determined. At the same time, the UE receives the active list and can assign ID codes of to active cells based on the order of entry of the cells on the list. Therefore, the UTRAN and the UE have corresponding information of the ID codes and the cells.
Moreover, the active list is renewed frequently and the renewed active list is provided to all active cells and the UE. After the SSDT and UE acknowledgement are activated, the UE starts to transmit the ID code of the primary cell, and the active cells start to detect primary cell ID information following a successful SSDT activation and admission of the UE acknowledgement.
The setting of temporary cell ID will next be explained.
A temporary ID is provided to cells during the SSDT for use as a site selection signal. In the SSDT mode, when an upper layer decides to make transmissions between a UE and a cell, the UE designates the most appropriate cell in the active cells as the primary cell and informs the UTRAN through the FBI field. Also, transmitting a signal to only one cell during the active SSDT mode can enhance a cell performance as intercellular interferences are reduced from the remaining other cells. The temporary cell ID is given as a binary bit sequence having a particular bit length, which is shown in Tables 3 and 4, below.
Table 3 shows temporary ID codes when the FBI is transmitted by one bit per slot, and Table 4 shows temporary ID codes when the FBI is transmitted by two bits per slot. As can be known from Tables 3 and 4, the temporary ID code may be in three forms of "Long," "Medium," and "Short," and there can be 8 codes for each of the forms. The temporary ID codes are required to be transmitted within one frame. If the space for sending a given ID code cannot be obtained within a frame, i.e. the entire ID cannot be transmitted within a frame but must be split over two frames, the last bit(s) of the temporary ID code is (are) punctured. In Table 3 and 4 below, the bit(s) to be punctured in such cases are shown with brackets.
TABLE 3ID codeID labelLongMediumShortA0000000000000000000000(0)00000B1111111111111111111111(1)11111C000000001111110000111(1)00011D1111111100000001111000(0)11100E0000111111110000011110(0)00110F1111000000001111100001(1)11001G0011110000111100110011(0)01010H1100001111000011001100(1)10101
In Table 3, the long ID code with a code length 15 has a maximized minimum hamming distance dmin max. 7; the medium ID code with a code length 8 has a maximized minimum hamming distance dmin max. 4; the ID code with a code length 7, having the last bit punctured in the medium ID code with a code length 8, has a maximized minimum hamming distance dmin max. 3; and the short ID code with a code length 5 has a maximized minimum hamming distance dmin max. 2.
TABLE 4ID codeID labelLongMediumShortA0000000(0)000(0)0000000000(0)000(0)000B1111111(1)111(1)1111111111(1)111(1)111C0000000(1)000(0)0001111111(1)111(1)111D1111111(1)111(1)1110000000(0)000(0)000E0000111(1)001(1)0011111000(0)110(0)100F1111000(0)110(0)1100000111(1)001(1)011G0011110(0)011(0)0100011110(0)011(0)010H1100001(1)100(1)1011100001(1)100(1)101
In the Table 4, the long ID code with a code length 16 has a maximized minimum hamming distance dmin max. 8; the ID code with a code length 14, having the last bit pair punctured in the long ID code with a code length 16, has a maximized minimum hamming distance dmin max. 6; the medium ID code with a code length 8 has a maximized minimum hamming distance dmin max. 4; the ID code with a code length 6, having the last bit punctured in the medium ID code with a code length 8; has a maximized minimum hamming distance dmin max. 2; and the short ID code with a code length 6 has a maximized minimum hamming distance dmin max. 2.
The following Table 5 shows a number of times of site selection permitted to select a primary cell per one frame for different forms of ID codes, according to the temporary ID code characteristics shown in Tables 3 and 4.
TABLE 5codea number of FBI bits assigned per slot for SSDTlength12ALong@one site selection pertwo site selection perframeframeAMedium@two site selection perfour site selection perframeframeAShort@three site selection perfive site selection perframeframe
Referring to Table 5, if the number of FBI bits per slot is 1, the number of site selection per frame is one using a long ID code because 15 bits, one bit per slot, can be transmitted in each frame. If the number of FBI bits per slot is 2, the number of site selection per frame is two because 30 bits, two bits per slot, can be transmitted in each frame. Similarly, if the number of FBI bits per slot is 1, the number of site selection per frame is 2 using a medium ID code and 3 using a short ID code. Finally, if the number of FBI bits per slot is 2, the number of site selection per frame is 4 using a medium ID code and 5 using a short ID code.
Furthermore, when two bits of FBI are transmitted per slot, the 8 long ID codes of 14 bit lengths have a maximum cross-correlation value of "2" and a maximized minimum hamming distance 6 (dmin=6) while the 8 medium ID codes of 6 bit lengths and the 8 short ID codes of 6 bit lengths respectively have a maximum cross-correlation value of "2" and a maximized minimum hamming distance 2 (dmin=2). Here, for the long ID code of 14 bits, 2 bits of the last column of Table 2 are puncture, and for the medium ID code with a code length of 6, 2 bits of the last column are also punctured.
As described before, when the UE assigns one of the temporary ID codes as the primary cell ID code and sends the primary cell ID code after the SSDT and the UE acknowledgement, the primary cell ID code is sent through the FBI field in the uplink control channel. Particularly, a cell is non-primary if the following three conditions are met, where NID is a length (a number of bits) of the generated temporary ID.                1. The received primary ID code does not match with its own ID code;        2. the received uplink signal quality satisfies a quality threshold defined by UTRAN; and        3. the number of symbols punctured in the uplink compressed mode is smaller than λNID/3μ.
Otherwise, if any one of the above three conditions are not met, a cell is maintained as a primary cell.
The termination of the SSDT is determined by the UTRAN. Particularly, the UTRAN terminates the SSDT in a method identical to a procedure for terminating the soft handover, and informs the termination to all cells and the UE. Thus, in the related art SSDT, performance of cell ID code used for identifying respective cells is dependent on the maximum cross-correlation value or the maximized minimum hamming distance. Accordingly, an optimal cell ID code which has a maximum cross-correlation value or a maximized minimum hamming distance is required, and a method for identifying a cell using the optimal cell ID code is required.

Method for generating and transmitting optimal cell ID codes


The tailgate drive includes a motor assembly in operable communication with a pickup tailgate that is adjustable between a manual mode of operation and an automatic mode of operation, where the motor assembly permits free rotation of the tailgate between the open and closed positions during manual mode of operation and wherein the motor assembly drives the tailgate body between the open and closed position during the automatic mode of operation.

During use, an owner of a pickup truck is required to repeatedly open and close the tailgate of his or her pickup truck to provide selective access to the cargo area of the truck. In particular instances, the user may be required to remove the tailgate from the truck so as to provide the necessary accommodations for larger loads. In modern truck designs, compromises must be struck to permit the installation of ever-greater number and types of features in the truck while still maintaining the ease of use the earlier designs contained.


A storage module and low-complexity methods for assessing the health of a flash memory device are disclosed. In one embodiment, data is written to a subset of memory cells in a memory of a storage module. Error statistics for the subset of memory cells are determined, and cell error rate parameters for the memory are estimated by fitting the determined error statistics for the subset of memory cells with a parametric statistical model. Other embodiments are possible, and each of the embodiments can be used alone or together in combination.

Because defects may occur when manufacturing a flash memory device, it is often preferred to test the memory during production in order to determine if the memory is "healthy" enough for its intended operation. Previous approaches for estimating a flash memory's health are implemented in the fabrication facility as part of the testing (qual) phase and are not performed during the memory's lifetime due to complexity of the testing procedure. Specifically, during the health test, reference data is written to multiple e-blocks (i.e., an error correction code (ECC) codeword) in the flash memory. The e-blocks are then read from memory, the data is decoded, and the error statistics are gathered from all of the data. Using the error statistics data, the "health" condition of the memory is estimated, and the memory is qualified or disqualified accordingly. These previous approaches for evaluating memory health involve storing large amounts of data, so health analysis is limited to production and testing times and could not be performed during normal operation of the memory device during its routine operation.

Storage module and low-complexity methods for assessing the health of a flash memory device


A universal wireless charging receiver for an electronic device is provided. The universal wireless charging receiver includes a base casing, a first magnetic shielding element, a power supply module and an induction coil. The first magnetic shielding element, the power supply module and the induction coil are installed in the base casing. The power supply module is located over the first magnetic shielding element. A magnetic field is shielded by the first magnetic shielding element. Consequently, an eddy current is not generated by the power supply module through the magnetic field.

In modern societies, portable electronic devices become indispensable parts in human lives. The electronic devices are applied in many sectors, including food, clothing, housing, transportation, education and entertainment. Generally, most of the portable electronic devices are powered by their built-in batteries. After the electrical quantity of the battery is used up, the user has to charge the battery of the electronic device. Consequently, the electronic device can be operated continuously.
Generally, the battery can be charged according to a wired charging technology or a wireless charging technology. According to the wireless charging technology, an induction coil is installed in the electronic device and electrically connected with the built-in battery of the electronic device. During operation, the electronic device is placed on a wireless charging dock, and a transmitter coil within the wireless charging dock generates a magnetic field. After the magnetic field is induced by the induction coil, a current is generated according to the change of the magnetic flux.
However, since some of the portable electronic devices are not equipped with the built-in wireless charging modules, these portable electronic devices cannot be wirelessly charged. For solving the above drawbacks, there is a need of providing a universal wireless charging receiver that can be applied to or installed in various electronic devices.


A video decoder receives to-be-decoded data from a bitstream for a block of pixels to be decoded as a current block of a current picture of the video. The video decoder generates a first prediction of the current block based on a first prediction mode that is selected from a first candidate list. The video decoder generates a second prediction of the current block based on a second prediction mode that is selected from a second candidate list. The video decoder generates a combined prediction for the current block based on the first prediction and the second prediction. The video decoder reconstructs the current block by using the combined prediction.

Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted as prior art by inclusion in this section.
High-Efficiency Video Coding (HEVC) is an international video coding standard developed by the Joint Collaborative Team on Video Coding (JCT-VC). HEVC is based on the hybrid block-based motion-compensated DCT-like transform coding architecture. The basic unit for compression, termed coding unit (CU), is a 2N×2N square block of pixels, and each CU can be recursively split into four smaller CUs until the predefined minimum size is reached. Each CU contains one or multiple prediction units (PUs). Each PU corresponds to a block of pixels in the CU.
To achieve the best coding efficiency of hybrid coding architecture, HEVC employs intra-prediction and/or inter-prediction modes for each PU. For intra-prediction modes, the spatial neighboring reconstructed pixels can be used to generate the directional predictions in 35 directions. For inter-prediction modes, motion information is used to reconstruct temporal reference frames, which are used to generate motion compensated predictions. Motion information may include motion vectors, motion vector predictors, motion vector differences, reference indices for selecting reference frames, etc.
There are three types of inter-prediction modes: skip mode, merge mode, and advanced motion vector prediction (AMVP) mode. Under AMVP mode, motion vectors (MVs) used for motion-compensated prediction of PUs are derived from motion vector predictors (MVPs) and motion vector differences (MVDs, or residual motion data) according to MV=MVP+MVD. For an AMVP-predicted PU, the MVP is selected from among a set of MVP candidates that includes two spatial candidates and one temporal candidate. An index that identifies the MVP selection is encoded and transmitted along with the corresponding MVD as motion information. Reference index for selecting a reference frame (or reference indices for selecting reference frames) from reference frame list L0 and/or L1 for bidirectional or unidirectional prediction is also encoded and transmitted as motion information.
When a PU is coded in either skip mode or merge mode, no motion information is transmitted except the merge index of the selected candidate. That is because skip mode and merge mode utilize motion inference methods (MV=MVP+MVD where MVD is zero) to obtain the motion information from spatially neighboring blocks (spatial candidates) or collocated blocks in temporally neighboring pictures (temporal candidates) that are selected from reference frame list L0 or L1 (indicated in slice header). In the case of a skip PU, the residual signal for the block being coded is also omitted. To relay motion information for a pixel block under HEVC by using AMVP, merge mode, or skip mode, an index is used to select an MVP (or motion predictor) from a list of candidate motion predictors. In merge/skip mode, a merge index is used to select an MVP from a list of candidate motion predictors that includes four spatial candidates and one temporal candidate. The merge index is transmitted, but motion predictors are not transmitted.

Merge candidates with multiple hypothesis


The invention relates to a method for changing gear stages in a transmission having a hydrostatic transmission and a downstream manual transmission, and a corresponding transmission arrangement. First, a desire to shift is detected within the manual transmission to change the gear stages. The hydrostatic transmission and the downstream manual transmission are activated to change the gear stage of the downstream transmission. Whether the gear stage to be engaged through a gear stage change was successfully engaged is detected by a detection device, which is connected to an electronic control unit of the transmission arrangement. If the engagement of the gear stage to be engaged is not successful, the original gear stage is reengaged. After the engagement of the original gear stage, the downstream transmission is again activated such that the gear stage to be engaged is engaged.

Field of the Invention
The present invention is based on a hand-held power tool.
Description of the Prior Art
DE 10 2005 058 937 A1 has disclosed a drive unit with a hydrostatic transmission and a manual transmission connected thereto. Such transmission arrangements are used, for example, for drive units in construction, farming, and forestry machines or the like. The manual transmission downstream of the hydrostatic transmission has at least two gear stages, during the shifting of which, a synchronizing device adapts the rotation speed of the hydraulic motor of the hydrostatic transmission to the respective driving situation and therefore to the rotation speed of the transmission input shaft of the downstream manual transmission. In order to facilitate this rotation speed adaptation, to avoid shifting jolts, and to improve overall driving comfort while reducing the load and therefore wear on the transmission arrangement, the above-cited patent application proposes adjusting the hydrostatic motor during the shifting procedure so that the rotation speed of the hydraulic motor is slightly greater than the rotation speed that precisely matches a driving situation. Once the rotation speed of the hydraulic motor has been correspondingly increased, then the downstream manual transmission is shifted into the intended gear.
In the above-described transmission arrangement and method for engaging a gear stage in the downstream manual transmission, it is problematic that in certain situations, it is not possible to assure reliable engagement of the intended gear. In particular, for example due to temperature fluctuations and production tolerances, it is not possible to successfully shift into the intended gear predetermined by the vehicle operator. However, in this transmission arrangement and method for shifting gears, no measures are provided for detecting the correct engagement of a gear stage. It is therefore finally left up to the operator to monitor the correct engagement of a gear stage and if need be, to repeat the gear shifting procedure.

Method for changing gear stages and transmission arrangement


A system identifies ancestral birth locations or surnames estimated to be associated with an individual's ancestors using an individual's genetic sample. The system identifies users who are genetic matches to the individual and determines whether and how often a birth location or surname appears in the pedigrees of those users. Birth locations or surnames that appear frequently throughout the pedigrees of genetically matching users may represent birth locations or surnames that are affiliated with the individual's ancestors. The system determines whether the frequency of appearance of a birth location or surname is statistically significant to eliminate biases for certain birth locations or surnames that appear more frequently than others. The birth location or surname may be provided to the individual based on an also-determined enrichment score.

This description generally relates to population analyses on human genetic and genealogical information, and particularly to using that information to identify ancestral birth locations or ancestral surnames for an individual.
An individual may often be interested in learning more about his/her ancestral history including ancestral birth locations and/or ancestral surnames. Families may have genealogical pedigrees or family trees that may be verbally passed down from generation to generation. However, these genealogical family trees become inaccurate as they are passed along or may be missing the birth location or surnames of past ancestors altogether. Therefore, an individual often cannot rely on genealogical data provided by a family member to identify ancestral birth locations or surnames.

Genetic and genealogical analysis for identification of birth location and surname information


An optical fiber filter including a length of single mode fiber having an operating wavelength .lambda..sub.0. Fiber designs may include a depressed inner clad fiber, a photosensitive matched inner clad fiber or a photosensitive depressed inner clad fiber. The length of fiber includes a core, an inner cladding, an outer cladding and an azimuthally asymmetric grating. The core allows the existence of a LP.sub.01 core mode having an effective index of n.sub.eff,01 and the cladding allows the existence of a LP.sub.1m cladding mode, m.gtoreq.1. The core has an index of refraction n.sub.co and a radius A. The inner cladding has an index of refraction n.sub.ic, an inner radius A, an outer radius AB, a thickness W, where W=AB-A, and a refraction difference .DELTA.n-, where .DELTA.n- is the difference between n.sub.ic and n.sub.oc and n.sub.co >n.sub.oc >n.sub.ic. The inner cladding may be photosensitive to a radius R.sub.grat and have a fractional photosensitivity .gamma.. The outer cladding generally laterally surrounds the inner cladding and has an inner radius AB, an outer radius B, and an index of refraction n.sub.oc, where .DELTA.n.sub.+ is the difference between n.sub.co and n.sub.oc. The grating has an effective tilt angle .theta. and a period (.LAMBDA.), where .LAMBDA..ltoreq.(.lambda..sub.0 cos .theta.)/(2n.sub.eff,01), the maximum relative coupling coefficient for the cladding mode max(RCC.sub.1m) being greater or equal to 0.2 and the ratio of peak reflectivities for the cladding mode and the core mode RR being greater or equal to 1.

1. Field of the Invention
The present invention relates generally to a narrowband rejection filter including a waveguide having an azimuthally asymmetric grating. More specifically, the present invention is directed to a single-mode depressed inner clad, photosensitive matched inner clad or photosensitive depressed inner clad optical fiber design having an azimuthally asymmetric photoinduced Bragg grating that couples out of a forward propagating LP.sub.01 core mode over a narrow wavelength band while practically suppressing backreflection. The present invention further relates to system applications of the novel filter design.
2. Description of Related Art
An optical fiber typically includes a core region of refractive index n.sub.co or n.sub.1. In double clad fiber designs, the core region is surrounded with an inner cladding having a refractive index n.sub.ic or n.sub.1a, which is in turn surrounded by an outer cladding region having a refractive index n.sub.oc or n.sub.2. The outer cladding is surrounded by an external medium having a refractive index n.sub.ext. A region of the fiber may be photosensitive.
The free parameters in double cladding waveguide designs are defined as follows:
MFD operational mode field diameter PA1 .lambda..sub.o operational wavelength PA1 .lambda..sub.c second mode cutoff wavelength PA1 A, r.sub.co core radius generated from a single effective step approximation of the core region PA1 W inner cladding width generated from a single effective step approximation of the inner cladding region PA1 B, r.sub.oc outer cladding radius PA1 n.sub.co, n.sub.1 core refractive index generated from a single effective step approximation of the core region PA1 n.sub.ic, n.sub.1a inner cladding refractive index generated from a single step approximation of the inner cladding region PA1 n.sub.oc, n.sub.2 outer cladding refractive index PA1 n.sub.ext external medium refractive index PA1 R.sub.grat maximum radius of photosensitive region of the fiber PA1 .gamma. fractional photosensitivity of photosensitive inner cladding as compared to the core, .gamma.=(grating strength in cladding)/(grating strength in core). (For example, .gamma.=1 means equal photosensitivity in core and inner cladding.)
"Grating tilt angle" is defined as the angle between the grating vector (the direction normal to the planes which define the grating periodicity) and the longitudinal axis of the fiber, where a physical tilt of the grating planes exists in the fiber.
"Effective grating tilt angle" is defined as the value of "grating tilt angle" that is shown experimentally to give cladding-mode loss equivalent to the cladding-mode loss when an azimuthal asymmetry other than a physical tilt of the grating fringes is present in a grating inscribed in the waveguide.
"Fundamental rejection notch" is defined to be the feature or dip in the transmission spectrum of the waveguide grating with the smallest value of transmission. Generally, this corresponds to the wavelength for which a reduction in the transmitted signal is desired.
"Cladding mode losses" refers to losses or dips in the observed transmission spectrum for a waveguide containing a grating that occur due to coupling of the forward propagating modes of the waveguide to counter-propagating bound cladding modes (in the case of n.sub.ext <n.sub.oc), or counter-propagating radiation modes (in the case of n.sub.ext .gtoreq.n.sub.oc). Peak cladding mode loss ("PCML") is the maximum "cladding mode loss" in a given transmission spectrum for a waveguide containing a grating.
A passive component that couples light out of the forward propagating LP.sub.01 core mode of a single-mode telecommunications fiber with relatively negligible backreflection over a narrow wavelength band is a critical filtering element for lightwave systems in which no backreflected signal can be tolerated.
The standard approach to filtering has been to couple the forward propagating LP.sub.01 mode to a counter propagating LP.sub.01 mode. Conventional Bragg gratings redirect the filtered signal back into the fiber. The higher the filtering ability of a traditional Bragg grating, the greater is the back reflection. However, in many systems, such as WDM applications, the back reflection may cause deleterious effects, such as destabilizing the signal emitting laser. Presently, an available alternative is to install isolators, which protect sensitive equipment. However, the current cost of isolators is high.
Work towards obtaining a narrowband rejection filter utilizing a grating in which the loss is not obtained through coupling to the counterpropagating LP.sub.01 core mode can be broken into two categories: coupling to the LP.sub.11 mode in a two mode fiber and coupling to cladding or radiation modes in a single-mode fiber.
Suppression of the forward propagating LP.sub.01 core mode over a narrow wavelength band was shown in a two mode fiber. The backreflected signal at the peak rejection wavelength due to coupling to the counter-propagating LP.sub.11 core mode was measured to be -15 dB, a value smaller than the commonly desired isolation for wavelength division multiplexing applications. In addition, two-mode fiber filters may have higher insertion losses than filters in single-mode fiber due to an imperfect mode-field match. Standard telecommunications fibers usually are single mode fibers.
Attempts towards suppression of the core mode using single mode fibers have discussed how in a strong, tilted grating, significant coupling to the LP.sub.1m modeset could occur. Additionally, outcoupling light from a single-mode fiber utilizing a transversely asymmetrically shaped Bragg grating has been attempted. However, these attempts have failed to couple a significant fraction of power from the fundamental mode.
The need remains for a filter design that allows for coupling out of the LP.sub.01 core mode with near, if not complete, suppression of coupling to the backward propagating fundamental mode.