An elongated frame member and a rectangular screen frame assembly including the frame member having a unique cross sectional shape of the frame member for the reception and retention of flexible fiberglass or other types of screening material without requiring a separate spline or locking strip component. The uniform frame member cross section includes a substantially box or rectangular shaped main portion and substantially U-shaped portion positioned adjacent said main portion, said U-shaped portion including spaced apart first and second side walls and a bottom wall therebetween. Each first side wall is preferably substantially common with or defined by one surface of said main portion. A first plurality of spaced apart resilient barbs each extend laterally in cantilevered fashion from the first side wall toward, but not to, the second side wall, while a second plurality of spaced apart resilient barbs each extend laterally in cantilevered fashion from the second side wall toward, but not to, the first side wall. The first and second plurality of barbs overlap each other in staggered fashion whereby a distal edge of each of the first and second plurality of barbs collectively define a serpentine or zigzag shaped screen retaining passage therebetween. These barbs are sufficiently resilient to be forcefully deflected to enlarge the width of, and somewhat straighten, the passage while the edge portion of the screen panel is inserted therein. The barbs resiliently return to a substantially at-rest position when released to lockingly engage and retain the screen edge portion in said passage while also tensioning the screen panel by drawing more of the margin into said passage.

SCOPE OF INVENTION
This invention relates to screen frame means for fiberglass screen or other types of screening material in screen frame assemblies such as window screens, patio screen doors and the like, and more particularly to a frame member for such screen frame assemblies which eliminates the need for the retaining spline conventionally used to retain screen panels in place.

Spineless screen frame assembly and screen frame member therefor


A semiconductor integrated circuit apparatus has a basic cell region formed by arranging a plurality of basic cells each including a MOS transistor in longitudinal and transversal directions. The MOS transistor has source-drain section diffusive regions formed on a semiconductor substrate, and a gate electrode formed on a channel region between these source-drain section diffusive regions through a gate insulating film. One portion or all of the channel region of at least one MOS transistor within the basic cell region has an impurity concentration different from that in the channel region of another MOS transistor of the same conductivity type within the same basic cell. For example, a threshold voltage in the channel region of a MOS transistor is increased until about 6 volts by implanting ions into the channel region. No MOS transistor is operated at a power voltage such as 5 volts and separates MOS transistors on both sides thereof from each other. Wiring is formed on the MOS transistor and the gate electrode is used as the wiring, thereby improving wiring efficiency.

1. Field of the Invention
The present invention relates to a semiconductor integrated circuit apparatus of a master slice type in which a plurality of basic cells including MOS transistors are regularly arranged. More particularly, the present invention relates to a semiconductor integrated circuit apparatus of a master slice type which is of a CMOS type of BiCMOS type and includes a MOS gate array and a MOS-composite gate array (which constitutes a semiconductor integrated circuit apparatus having a gate array structure in one portion of a semiconductor chip), or a MOS transistor of a P-channel type (which is called a PMOS transistor in the following description) and a MOS transistor of an N-channel type (which is called an NMOS transistor in the following description) in a basic cell. The present invention also relates to a method for manufacturing the semiconductor integrated circuit apparatus.
2. Description of the Related Art
A field insulating film is used as a first example to separate electric elements from each other in a MOS transistor. In a second example, a turning-off MOS transistor having a gate electrode connected to a power source is used to separate electric elements from each other in a MOS transistor.
For example, basic gates separated from each other by the field insulating film have generally two inputs. Accordingly, when a circuit structure is constructed such that the basic gates have three or five inputs, there are unused gate electrodes so that flexibility with respect to the number of input signals is low.
In an element separating region, it is necessary to dispose a region for connecting a gate electrode to power source wiring, thereby reducing wiring efficiency. Further, it is impossible to use this gate electrode in wiring so that the wiring efficiency is further reduced.
A general surge protecting element is constructed by a MOS transistor equal to that constituting an internal logic circuit. Accordingly, no drain withstand voltage of the protecting element is reduced by taking various kinds of measures for securing reliability of the MOS transistor. Therefore, a gate withstand voltage is set to be lower than the drain withstand voltage of the protecting element as a size of the protecting element is reduced. In such a reversing phenomenon, such a protecting element cannot function as a normal protecting element.
In a general diode having a PN-junction, a backward withstand voltage depends on temperature so that this diode cannot be used as a constant voltage circuit.
When a logic circuit is constructed by using a general CMOS-type master slice and its logic threshold voltage is changed, it is necessary to dispose plural PMOS and NMOS transistors. Therefore, an area for these MOS transistors is increased on a master slice chip.
Further, the number of used PMOS transistors is not necessarily in conformity with the number of used NMOS transistors. Accordingly, some MOS transistors are unused and the size of a circuit structure is increased.
As mentioned above, each of the PMOS and NMOS transistors included in a basic cell has a constant size. Accordingly, this size is larger than the size of a minimum transistor required to flow a required electric current therethrough so that a direct electric current excessively flows through the MOS transistors.
In a semiconductor integrated circuit apparatus of a master slice type, each of the PMOS and NMOS transistors is set to have an intrinsic channel width. Therefore, if a memory cell is formed in the semiconductor integrated circuit apparatus of a master slice type, the number of used gates is increased and an area for the memory cell is increased.
In another proposed method, a basic unit of the semiconductor integrated circuit apparatus of a master slice type is set by adding PMOS and NMOS transistors and an NMOS transistor of a size smaller than that of each of the PMOS and NMOS transistors to a basic unit cell. When a memory is constructed, the small-sized NMOS transistor is used as an access gate. For example, such a method is shown in "Monthly Semiconductor World" published in February in 1990, pp. 92 to 95. However, in this method, an area for the basic unit cell is increased by adding the small-sized NMOS transistor to this basic unit cell.
In a static RAM, complementary signals on are generally required in a writing operation. To provide a SRAM of high density, there is a method for reducing the number of data lines (bit lines) and the number of MOS transistors by setting each of the complementary signals in the writing operation to a single signal. However, it is necessary to insert an inverter between an access gate and a latch section so as to prevent read data from being fed back to a memory cell. Therefore, it is impossible to provide the SRAM of high density in a semiconductor integrated circuit of a master slice type.
Further, there is another SRAM in which an initial state of the memory cell can be set to prevent this initial state from being undefined when a power source is turned on. The initial state of the memory cell is set by changing operating characteristics thereof as one example of the SRAM. In this example, the size of a MOS transistor constituting the memory cell is changed by changing the width of a diffusive layer of the MOS transistor. The initial state of the memory cell is set by arbitrarily setting the operating characteristics of the memory cell. There is another memory cell for setting the initial state by changing memory cell circuits. For example, such a structure is shown in Japanese Patent Publication (KOKOKU) Nos. 2-30118 and 2-17875.
However, no method for changing the width of the diffusive layer to change the operating characteristics of the memory cell can be applied to the semiconductor integrated circuit apparatus of a master slice type. Further, in the method for changing electric circuits of the memory cell, the electric circuits must be changed in accordance with a set value of the memory cell.

Array of field effect transistors of different threshold voltages in same semiconductor integrated circuit


A reader comprises a feeding path for boarding pass to be inserted in various orientations, pairs of feeding rollers for transporting the boarding pass along the path, and four sensor units arranged along the path each for sensing a signal recorded on the boarding pass inserted in a particular orientation. The reader also comprises a demodulation unit for demodulating each signal sensed by the sensor units, a monitoring circuit for determining which one of the sensor units of has sensed the recorded signal, a switch circuit, for electrically connecting the demodulation unit to the sensor unit which the monitor circuit determines has sensed the recorded signal, and a read circuit for reading flight information by extracting a series of digital data from each demodulated signal output by the demodulation unit and converting the series of digital data into the parallel form in accordance with the particular orientation of the boarding pass facing the sensor unit which the monitor circuit determines has sensed the recorded signal.

1. Field of the Invention
This invention relates to a reader to read the information magnetically recorded on a card such as a boarding pass.
2. Description of the Related Art
A boarding pass having a magnetic stripe has recently come into use in airports in order to simplify the examination of tickets. As shown in FIG. 1, this magnetic stripe MS is bonded on the back of the boarding pass PS and stores the passenger flight information including a flight number, seat number, passenger name, tag number, etc. The flight information is recorded on the magnetic stripe MS through parallel-to-serial conversion and modulation. Some pieces of the information are printed o the surface of the boarding pass. Passengers receive boarding passe at the traveler's counter, advance to the boarding gate to the plane, and insert the boarding passes into the reader installed at the boarding gate. The reader reads the flight information from each boarding pass to confirm that the boarding pass is effective.
The reader has four magnetic heads and four demodulation units, which cooperate to read the flight information regardless of the orientation of the boarding pass inserted into the feeding path. The first and second magnetic heads are located under the feeding path and spaced apart in the widthwise direction of the path. The third and fourth magnetic heads are arranged above the feeding path and spaced apart in the widthwise direction of the path. The magnetic stripe of the boarding pass faces the first magnetic head when the pass is correctly inserted, the second magnetic head when it is inserted with the front side back, the third magnetic head when it is inserted inside out, and the fourth magnetic head when it is inserted the front side back and inside out. Each magnetic head detects the signal recorded on the facing magnetic stripe. Each demodulation unit demodulates the signal sensed by the corresponding magnetic head and supplies the demodulated signal to the read circuit. The read circuit includes a microprocessor, which reads the flight information by extracting a series of digital data from the demodulated signal and converts them into the parallel form.
Information can be read from the boarding pass at high speed, since the magnetic stripe MS consists of four tracks TR1 to TR4, and the flight information is divided into four groups recorded on four tracks, respectively. Therefore, each magnetic head is constructed so as to read signals from the four tracks simultaneously, and each demodulation unit includes four independent demodulation ICs for processing the signals read from the four tracks, respectively.
Hence, the reader has 16 demodulation ICs in all, making it difficult to render the reader compact or to reduce the manufacturing cost thereof. In future, the magnetic stripe will have more and more tracks because of fractionation of flight information. In this case, the above problem will be all the more serious.
Moreover, since the read circuit of the reader must respond to the signal output from any demodulation unit, it is not easy to modify the software for controlling the operation of the microprocessor incorporated in the read circuit. If the number of tracks is increased, the manufacturing cost will greatly increase because it is necessary to modify the software as well as the addition of hardware.

Apparatus for reading a magnetic stripe on a boarding pass regardless of the orientation of the boarding pass


The present invention provides recombinant double stranded RNA phages (rdsRP) that express dsRNA-encoded genes in eukaryote cells. Recombinant dsRNA phages are useful for the expression of dsRNA expression cassettes encoding passenger genes, such as, but not restricted to, vaccine antigens, bioactive proteins, immunoregulatory proteins, antisense RNAs, and catalytic RNAs in eukaryotic cells or tissues. Methods are provided to deliver a recombinant dsRNA phage to eukaryotic cells and tissues, either by direct administration, formulated in lipid or polylactidecoglycolide, or by utilizing a bacterial vaccine vector.

1. Field of the Invention
The present invention generally relates to double stranded RNA phages, and more particularly, to recombinant double stranded RNA phages (hereinafter rdsRP) that express dsRNA-encoded genes in eukaryotic cells and used for the expression of dsRNA expression cassettes encoding passenger genes.
2. Background of the Related Art
Double stranded RNA phage (herein "dsRP") are atypical compared to other RNA and DNA phage, and more closely resemble members of the reoviridae family [1-5]. The distinguishing attributes of dsRP are a genome comprised of three double-stranded RNA (herein "dsRNA") segments [2-4,6] and a lipid-containing membrane coat [7-12]. The genomic segments are contained within the nucleocapsid core, which is comprised of the proteins P1, P2, P4, and P7, and is produced by genes encoded on the 7051 bp dsRNA segment, designated "segment L" (GeneBank Accession # AF226851). Synthesis of positive-strand RNA (herein "mRNA") occurs within the nucleocapsid, which is carried out by RNA-dependent RNA polymerase that may be encoded by gene 2 on segment L, based on sequence similarity to other bacterial RNA polymerases [4,13]. However, gene 7 on segment L also plays a pivotal role in mRNA synthesis [5].
DsRP phi-6, the archetype of this family of dsRNA phage, normally infects Pseudomonas syringae [5], however, more recently isolated dsRP phi-8, phi-11, phi-12 and phi-13 can replicate to some extent in Escherichia coli strain JM109 (American type tissue culture collection (herein "ATCC" # 53323) and O-antigen negative mutants of Salmonella enterica serovar Typhimurium (herein designated "S. typhimurium") [5,14-16].
By inserting a kanamycin-resistance allele into the M-segment of a dsRP, carrier strains were established and maintained [17]. Through this approach, several of the dsRPs were found to be capable of establishing a carrier state in host cells, in which infectious phage are continuously produced by the carrier strain [17]. The plaque-forming capacity of the phage produced by the carrier strains is maintained for three-five plate passages; however, after additional passages the nascent phage no longer formed plaques on the carrier strain, yet low-levels of infectious phage were still produced [17]. In some instances, a significant number of carrier strains lost the ability to produce infectious phage all together, yet phage dsRNA segments were continuously maintained in the cytosol of such carrier bacteria. The dsRNA from such bacterial strains displayed deletions in one of more of the segments. In one instance a mutant phage lacking the segment-S was isolated from one such carrier strain that had lost the capacity to produce phage [17,18].
The life cycle of the dsRP phi-6 in bacteria has been described [5,11]. Archetype dsRP phi-6 infects host cells by binding to the pilus. The phage then uses the pilus to allow contact with the host cell membrane, thereby resulting in fusion and introduction of the nucleocapsid into the periplasm. The nucleocapsid then is transported into the cytoplasm, an event that requires the endopeptidase activity of protein P5 and the transporting property of protein P8. Interestingly, nucleocapsids that bear a complete P8 shell are capable of spontaneous entry into bacterial protoplasts, resulting in auto-transfection of the bacterial strain from which the protoplasts were prepared [19,20].
Upon entering the cytoplasm, P8 is shed and the remaining nucleocapsid, which contains the three dsRNA segments and possesses RNA-dependent RNA polymerase activity, begins to synthesize mRNA copies of the dsRNA segments L, M and S as shown in FIG. 1. The proteins produced by segment L is mainly associated with procapsid production; segment M is mainly dedicated to the synthesis of the attachment proteins and the segment S produces the procapsid shell protein (P8), the lytic endopeptidase (P5), and the proteins (P9 and P12) involved in the generation of the lipid envelope [12] (FIG. 1).
Packaging of the dsRNA segments occurs in sequential manner, whereby segment S is recognized and taken up by empty procapsids; procapsids containing segment S no longer binds this segment but now are capable of binding and taking up segment M; procapsids that contain segments S and M no longer bind these segments but now are capable of binding and taking up segment L, resulting in the generation of the nucleocapsid. Once the nucleocapsid contains all three single-stranded RNA (herein "ssRNA") segments synthesis of the negative RNA strands begins to produce the dsRNA segments. The nucleocapsid then associates with proteins 5 and 8 as illustrated in FIG. 1 and finally is encapsulated in the lipid membrane, resulting the completion of phage assembly. Lysis of the host cell is thought to occur through the accumulation of the membrane disrupter protein P10, a product of segment M and requires the endopeptidase P5 [5].
The assembly of RNA polymerase and its activity in dsRP procapsids does not require host proteins, as procapsids purified from an E. coli JM109 derivative that expressed a cDNA copy of segment L are capable of packaging purified ssRNA segments L, M and S [5,19-24]. Following uptake of the ssRNA segments in the above in vitro system, addition of ribonucleotides resulted in negative strand synthesis and the generation of the mature dsRNA segments [5,19-24]. Furthermore, after the completion of dsRNA synthesis P8 associates with nucleocapsids and as indicated above the resultant product is capable of entering bacterial protoplasts and producing a productive infection [19,20].
There are several techniques for introducing nucleic acids into eukaryotic cells cultured in vitro. These include chemical methods (Felgner et al, Proc. Natl. Acad. Sci., USA, 84:7413-7417 (1987); Bothwell et al, Methods for Cloning and Analysis of Eukaryotic Genes, Eds., Jones and Bartlett Publishers Inc., Boston, Mass. (1990), Ausubel et al, Short Protocols in Molecular Biology, John Wiley and Sons, New York, N.Y. (1992); and Farhood, Annal. N.Y. Acad. Sci., 716:23-34 (1994)), use of protoplasts (Bothwell, supra) or electrical pulses (Vatteroni et al, Mutn. Res., 291:163-169 (1993); Sabelnikov, Prog. Biophys. Mol. Biol., 62:119-152 (1994); Brothwell et al, supra; and Ausubel, et al, supra), use of attenuated viruses [25-34](Moss, Dev. Biol. Stan., 82:55-63 (1994); and Brothwell et al, supra), as well as physical methods (Fynan et al, supra; Johnston et al, Meth. Cell Biol, 43(Part A):353-365 (1994); Brothwell et al, supra; and Ausubel et al, supra).
Successful delivery of nucleic acids to animal tissue has been achieved by cationic liposomes (Watanabe et al, Mol. Reprod. Dev., 38:268-274 (1994)), direct injection of naked DNA or RNA into animal muscle tissue (Robinson et al, Vacc., 11:957-960 (1993); Hoffman et al, Vacc., 12:1529-1533; (1994); Xiang et al, Virol., 199:132-140 (1994); Webster et al, Vacc., 12:1495-1498 (1994); Davis et al, Vacc., 12:1503-1509 (1994); and Davis et al, Hum. Molec. Gen., 2:1847-1851 (1993); [35,36]), and embryos (Naito et al, Mol. Reprod. Dev., 39:153-161 (1994); and Burdon et al, Mol Reprod. Dev., 33:436-442 (1992)), intramuscular injection of self replicating RNA vaccines [25-28,35,36] or intradermal injection of DNA using "gene gun" technology (Johnston et al, supra).
The ribosomal binding site (RBS) is the site recognized by the ribosome for binding to the 5-prime (herein designated "5′") end of mRNA molecules. This binding is essential for the translation of mRNA into a protein by the ribosome. In prokaryotes, a defined RBS in the 5′ end of the mRNA molecule that bears a sequence that is complementary to the 3′ end of the small ribosomal RNA molecule (5S rRNA) (Chatteiji et al, Ind. J. Biochem. Biophys., 29:128-134 (1992); and Darnell et al, supra; Lewin, supra; Watson et al, supra; and Watson et al, supra). Thus, in prokaryotes the RBS promotes association of the ribosome with the 5′ end of the nascent mRNA molecule, whereupon translation is initiated at the first initiation codon encountered (i.e. normally the methionine codon AUG) by the mRNA-associated ribosome (Darnell et al, supra; Lewin, supra; Watson et al, supra; and Alberts et al, supra).
At present, no such recognition pattern has been observed in the 5′ eukaryotic mRNA-ribosome interactions (Eick et al., supra). In addition, prior to initiation of translation of eukaryotic mRNA, the 5′ end of the mRNA molecule is "capped" by addition of methylated guanylate to the first mRNA nucleotide residue (Darnell et al, supra; Lewin, supra; Watson et al, supra; and Alberts et al, supra). It has been proposed that recognition of the translational start site in mRNA by the eukaryotic ribosomes involves recognition of the cap, followed by binding to specific sequences surrounding the initiation codon on the mRNA.
It is possible for cap independent translation initiation to occur and/or to place multiple eukaryotic coding sequences within a eukaryotic expression cassette if a internal ribosome entry site (herein "IRES") sequence, such as the cap-independent translation enhancer (herein designated "CITE") derived from encephalomyocarditis virus (Duke et al, J. Virol., 66:1602-1609 (1992)), is included prior to, or between, the coding regions. However, the initiating AUG codon is not necessarily the first AUG codon encountered by the ribosome (Louis et al, Molec. Biol. Rep., 13:103-115 (1988); and Voorma et al, Molec. Biol. Rep., 19:139-145 (1994); Lewin, supra; Watson et al, supra; and Alberts et al, supra). Thus, RBS sequences in eukaryotes are sufficiently divergent from that of prokaryotic RBS such that the two are not interchangeable.
The commercial application of nucleic acid delivery technology to eukaryotic cells is broad and includes delivery of vaccine antigens (Fynan et al, Proc. Natl. Acad. Sci., USA, 90:11478-11482 (1993)), immunotherapeutic agents, and bioactive proteins designed to remedy genetic disorders (Darris et al, Cancer, 74(3 Suppl.): 1021-1025 (1994); Magrath, Ann. Oncol., 5(Suppl 1):67-70 (1994); Milligan et al, Ann. NY Acad. Sci., 716:228-241 (1994); Schreier, Pharma. Acta Helv., 68:145-159 (1994); Cech, Biochem. Soc. Trans., 21:229-234 (1993); Cech, Gene, 135:33-36 (1993); Long et al, FASEB J., 7:25-30 (1993); and Rosi et al, Pharm. Therap., 50:245-254 1991)).
The delivery of nucleic acids to animal tissue for gene therapy has shown significant promise in experimental animals and volunteers, particularly where a transient effect is required (Nabel, Circulation, 91:541-548 (1995); Coovert et al, Curr. Opin. Neuro., 7:463-470 (1994); Foa, Bill. Clin. Haemat., 2:421-434 (1994); Bowers et al, J. Am. Diet. Assoc., 95:53-59 (1995); Perales et al, Eur. J. Biochem., 226:255-266 (1994); Danko et al, Vacc., 12:1499-1502 (1994); Conry et al, Canc. Res., 54:1164-1168 (1994); and Smith, J. Hemat., 1:155-166 (1992)). Recently, naked DNA vaccines carrying eukaryotic expression cassettes have been used to successfully immunize against influenza both in chickens (Robinson et al, supra) and ferrets (Webster et al, Vacc., 12:1495-1498 (1994)); against Plasmodium yoelii in mice (Hoffman et al, supra); against rabies in mice (Xiang et al, supra); against human carcinoembryonic antigen in mice (Conry et al, supra) and against hepatitis B in mice (Davis et al, supra). These observations open the additional possibility that delivery of nucleic acids to eukaryotic tissue could be used for both prophylactic and therapeutic applications, wherein the prophylactic application has a significant impact in the mortality and/or morbidity of the infectious agent, autoimmune disease or tumor prior to the acquisition of overt clinical disease, and the therapeutic application has a significant impact in the mortality and/or morbidity of the infectious agent, autoimmune disease or tumor following the development of overt clinical disease.
Therefore, there is a need to deliver eukaryotic expression cassettes, encoding endogenous or foreign genes that are vaccines or therapeutic agents to eukaryotic cells or tissue.

This patent is subject to a terminal disclaimer.

Recombinant double-stranded RNA phages and uses thereof

University of Maryland Biotechnology Institute


A welding tool for TIG arc welding, plasma welding or laser welding, including a welding head carrying a refractory electrode and surrounded by a skirt. The skirt is releasably fastened on the welding head and has a front portion which extends forwards and is shaped to surround a weld head with clearance over a predetermined length. The skirt is made by molding or thermoforming a composite material made of at least two layers of ceramic fibers which are bonded together by an elastomer that withstands high temperatures.

A TIG arc welding tool or a plasma welding tool comprises a head carrying a refractory electrode, such as a rod of non-meltable tungsten, capable of generating an electric arc in association with workpieces to be assembled together so as to form a weld bead between them by melting and mixing their materials.
A laser welding tool comprises a laser generator capable of generating a high energy beam that is applied to the workpieces to form a weld bead between them by melting and mixing their materials.
Such welding tools include means for feeding an inert gas to the head of the tool, the inert gas being for projecting onto the weld bead formed by the molten materials so as to protect said materials against oxidation by the ambient atmosphere.
In order to improve the protection, welders are in the habit of forming a cap of refractory adhesive tape around the welding head in order to confine the inert gas around the weld bead that is being formed and thus improve the quality of the welding.
Such caps are fragile and need to be replaced often, their shapes are not very accurate and poorly adapted to the workpieces, and different from one cap to another, and they are relatively time-consuming to make.


A plant for the treatment of waste water on board of vessels having a collection tank of black water and grey water, a primary treatment unit including a band filter, a secondary treatment unit including a micro-filtration or ultra-filtration module and a tertiary treatment unit including an ozone treatment module is provided.

The invention relates to the treatment of waste water on board of boats and ships, being directed in particular to providing passenger ships, ferries, off-shore rigs or barges with means with purifying water in order to either reuse the water for various purposes or to effect the subsequent outboard discharge in compliance with international standards and local regulations.
A reference value for the typical average daily consumption of drinking water on cruise ships is 247 litres per person, producing:                Black water: 25.5 l/p/d (litres/person/day) with an organic load (BOD) of 51 g/p/d (grams/person/day) and with a load of solids (TSS) of 38 g/p/d.        Grey water coming from housings: 112.2 l/p/d, with an organic load (BOD) of 22 g/p/d, and with a load of solids (TSS) of 11 g/p/d.        Grey water coming from the laundries: 35.7 l/p/d, with an organic load (BOD) of 11 g/p/d, and with a load of solids (TSS) of 11 g/p/d.        Grey water from kitchen and food preparation premises (galley): 73.9 l/p/d, with an organic load (BOD) of 148 g/p/d, and with a load of solids (TSS) of 185 g/p/d.
Normally, only systems for treating black water are used on board of ships. As in ground plants, they involve the use of aerobic digestion—albeit on a small scale due to evident space limitations—which consists of the metabolisation of organic substances through micro-organisms, whose development is conditioned by the presence of oxygen.
This process requires a long time for the metabolisation and must function in continuous, with no possibility of being turned on or off on command depending on the needs. Furthermore, it also requires the presence of expert personnel for an appropriate management. Grey water and treated black water are stored in appropriate storage tanks for subsequent processing or disposal on land.
It would be desirable to provide a plant for treating waste water on board of vessels overcoming the limitations of the prior art, in particular a plant of suitably small size for direct treatment of black and grey water until satisfying the requirements for reuse and/or outboard discharge in terms of effluent quality, with minimum generation of biomass requiring a subsequent disposal on land. It would also be desirable to provide a plant capable of being turned on and off on command and requiring no chemicals for treatment.

Plant for the treatment of waste water on board of vessels


The present invention provides a content data retrieval apparatus capable of appropriately narrowing down the range of search targets even in the case where a distribution of attribute values of a group of contents regarded as search targets is uneven.

Presently, advances in network environments, such as the Internet, and in technology for compressing digital data has made it possible to obtain a large amount of content data such as music data and video data. Conventionally, using a search word indicating an attribute such as a characteristic and a property of the content has been used to retrieve content data desired by the user.
In the conventional system for retrieving content data using a search word, an attribute value indicating a content attribute is assigned to each content data. The search word is converted into information indicating the range of the attribute value associated with the search word. Then, pieces of content data specified by the attribute values included in the range of the attribute value are outputted as search results.
Such content data retrieving system as described above include a music retrieval system for retrieving music data using impression words (e.g. Japanese Laid-Open Patent Application No. 2004_-86189). An impression word is a qualitative word representing an impression on music content, e.g., "relaxing".
According to the music retrieval system, an impression value is an index value representing an impression of the music set in advance for each music data. Moreover, an impression word inputted as a search word is converted to indicate the range of the corresponding impression value. The respective music data specified by the impression values included in the range of the impression value are retrieved as search results.
The music retrieval system is applied, for example, to car navigation apparatuses and PC music playback software.
With the conventional music retrieval system using impression words, however, the range of the impression value associated with an impression word is determined in a fixed manner. Therefore, in the case where the distribution of the impression values of respective pieces of music regarded as search targets is uneven, music is searched out only in the case of conducting a search using a specific impression word.
For example, in the case where a search target is a group of music obtained as a result of conducting a search using a specific artist's name, the impressions of many pieces of music are similar. That is to say that the absolute positions, within a space where impression values are presented, of the impression values of the respective pieces of music are close to each other. Therefore, in the case of conducting a search using an impression word, numerous pieces of music are selected for a specific impression word whereas no music is retrieved for an impression word other than that specific impression word.
Although a given impression word is the same, the range of the impression word intended by the user differs, e.g., the impression word "relaxing" used for the music performed by a rock artist who sings intensive music differs from the impression word "relaxing" used for the music performed by a female artist who sings calm music. This is because the user subconsciously knows that the possible range of impression values of music differs depending on an artist or a genre of the music, and thus represents, with an impression word, an impression relatively perceived in a group of music performed by the artist. However, the conventional music retrieval system using impression words does not take this point into consideration.
Thus, with the conventional music retrieval system using impression words, when the distribution of the impression values of the respective pieces of music regarded as search targets is uneven, the search results vary as well. As a result, the search results which reflect the user's intention cannot be outputted. In other words, it is not possible to narrow down the range of search targets, which is expected by the user.
The present invention is conceived in view of the above problem, and an object of the present invention is to provide a content data retrieval apparatus which retrieves, using a search word, the content data associated with an attribute value indicating a content attribute, and which appropriately narrows down the range of search targets even in the case where the distribution of attribute values for a group of contents regarded as search targets is uneven.

Abstract: The content data retrieval apparatus of the present invention includes: an impression value database which stores attribute values; a conversion table in which an impression value is associated with a search word range that is a range of the attribute values associated with a search word; a range modification unit which modifies a relative relationship between a distribution range of attribute values and a search word range by modifying the search word range read out from the conversion table; a receiving unit which receives an input of a search word; and a retrieval unit which retrieves content data corresponding to the search word received by the receiving unit, by searching the attribute values included in the search word range associated with the search word.


A composition for removing a radioactive element or compound such as systemic transuranic compounds, from mammals comprises a pharmaceutical carrier and a decorporation agent comprising ester and amide derivatives of DTPA. A method of treating a mammal to remove systemic compounds utilizing the DTPA derivatives is also disclosed.

The calcium and zinc salts of diethylenetriamine penta-acetate (Ca-DTPA and Zn-DTPA) have been approved by the Food and Drug Administration for the decoporation, removal or elimination of known or suspected internal contamination of humans with the transuranic metals (Z>92), plutonium, americium and curium. More specifically Ca-DTPA and Zn-DTPA are chelating agents that work by binding and holding onto radioactive materials or certain other poisons that enter the body. Once bound to the radioactive material or poison, the chelating agent is then passed from the body in the urine and or feces. The chelating agents help decrease the amount of time it takes to get the poison out of the body.
Ca-DTPA and Zn-DTPA are not absorbed from the GI tract to any appreciable extent and therefore must be administered by (1) subcutaneous injection directly into a vein, (2) intravenously by dripping into a vein from a bag or (3) by nebulized inhalation by means of a mist or spray breathed into the lungs.
A need exists for the development of a form of diethylene triamine penta-acetic acid (DTPA) that can be administered orally for use in the possible event of a massive radiation poisoning emergency such as could occur by the detonation of a dirty bomb by terrorists or inadvertent release of radioactivity into a work place or the environment. The present invention relates to pharmaceutical compositions and treatment methods meeting this need. More specifically, esters and amides of DTPA have been developed that are readily absorbed following oral administration and are subsequently and rapidly hydrolyzed back to active DTPA by esterases or amidases normally present in the intestinal lumen, liver and/or blood.

Methods and pharmaceutical compositions for decorporation of radioactive compounds

University of Kentucky Research Foundation


Some embodiments relate to an integrated chip including a memory device. The memory device includes a bottom electrode disposed over a semiconductor substrate. An upper electrode is disposed over the bottom electrode. An intercalated metal/dielectric structure is sandwiched between the bottom electrode and the upper electrode. The intercalated metal/dielectric structure comprises a lower dielectric layer over the bottom electrode, an upper dielectric layer over the lower dielectric layer, and a first metal layer separating the upper dielectric layer from the lower dielectric layer.

Many modern day electronic devices contain electronic memory configured to store data. Electronic memory may be volatile memory or non-volatile memory. Volatile memory stores data when it is powered, while non-volatile memory is able to store data when power is removed. There are many different types of non-volatile memory that fall within the present disclosure, including Programmable Metallization Cell (PMC) Random Access Memory (RAM) (also referred to in some contexts as Conductive Bridge RAM (CBRAM)), Phase Change RAM (PCRAM), oxide based RAM (OxRAM), Magnetic RAM (MRAM), Resistive RAM (RRAM), etc. RRAM in particular is one promising candidate for a next generation non-volatile memory technology. RRAM has a simple structure, consumes a small cell area, has a low switching voltage and fast switching times, and is compatible with CMOS fabrication processes.

Intercalated metal/dielectric structure for nonvolatile memory devices

Taiwan Semiconductor Manufacturing Co., Ltd.


Disclosed is a refrigerator having a height-adjustable door. The body of the refrigerator has at least one storage space having a front opening. The door is coupled to the body so as to cover/uncover the storage space, and a hinge hole is formed on the bottom surface of the door. A hinge frame is fixed to a front surface of a lower portion of the body and has a hinge shaft inserted into the hinge hole so as to rotatably support the door. The hinge shaft is covered with a hinge bush, a part of which is inserted into the hinge hole. The hinge bush has a flange portion on its lower end for supporting the bottom surface of the door. A height adjustment screw is screw-coupled to a screw hole of the hinge frame so as to travel vertically. The upper end of the height adjustment screw abuts the bottom surface of the hinge bush so that, when rotated, the height adjustment screw lifts/lowers the hinge bush, in order to adjust the height of the door.

1. Field of the Invention
The present invention relates to a refrigerator having a height-adjustable door, and more particularly to a refrigerator having a height-adjustable door, the height of which can be adjusted easily.
2. Description of the Prior Art
FIG. 1 is a perspective view showing the structure of a conventional side-by-side type refrigerator. FIG. 2 is a sectional view showing a support structure for rotatably supporting a door of a refrigerator according to the prior art.
Referring to FIG. 1, the conventional refrigerator includes a body 10 provided with freezing and refrigerating chambers 11 and 12, which have front openings, and freezing and refrigerating chamber doors 21 and 22 for covering/uncovering the front openings of the freezing and refrigerating chambers 11 and 12, respectively. The freezing and refrigerating chamber doors 21 and 22 are rotatably supported on the upper and lower ends of both sides of the body so that the freezing and refrigerating chambers are covered/uncovered.
A conventional structure for supporting the doors 21 and 22 will now be described with reference to FIG. 2. The doors 21 and 22 are supported so as to rotate relative to the body 10, in order to cover/uncover the front openings of the freezing and refrigerating chamber 11 and 12. The doors 21 and 22 have hinge holes 23 formed on their bottom surfaces in the longitudinal direction. The body 10 has hinge frames 31 fixed to its lower end and hinge shafts 31a positioned on the hinge frames 31 so that the hinge shafts 31a are inserted into the hinge holes 23 and rotatably support the doors 21 and 22.
The hinge frames 31 are fixed to the body 10 with bolts or by welding, for example, and have hinge bushes 32 fitted to the hinge shafts 31a. Particularly, the hinge bushes 32 are configured so as to enclose the hinge shafts 31a and have rotation shafts 32a, which are inserted into the hinge holes 23 and rotatably support the doors 21 and 22 directly.
The upper ends of the doors are similarly supported by hinge devices (not shown) so that the doors can rotate. It can be easily understood by those skilled in the art that the hinge devices (not shown) for supporting the upper ends of the doors do not bear the weight of the doors, but simply provide shafts for rotation of the doors, while the hinge frames 31, shown in the drawing, directly bear the weight of the doors.
Such a conventional refrigerator has a problem in that the freezing and refrigerating doors 21 and 22 may not be completely level with each other due to an assembly tolerance, or they may be displaced downwards by repeated opening/closing operations. This results in a discrepancy in height between the doors 21 and 22.
In order to remove such a discrepancy in height, the doors 21 and 22 must be completely separated from the body 10 and the hinge frames 31 must be repositioned in an inefficient and inconvenient manner, because the height of the doors 21 and 22 are determined in the initial assembly process.

Refrigerator having height-adjustable door


A process for producing an artificial tooth comprising: injection molding polymerizable material into a mold to form an outer external polymeric layer. Then injection molding polymerizable material into the mold to form an inner polymeric layer applied on the first external layer. Then injection molding polymerizable material into the mold to form a solid core applied on the inner external layer.

The invention relates to injection molding of polymerizable material to form prosthetic teeth of polymeric material consisting of several layers.
Dehoff et al, the disclosure of which is incorporated herein by reference in its entirety, disclose prosthetic teeth. Roemer, et al. in U.S. Pat. No. 4,396,476 ,and U.S. patent application Ser. No. 09/333,727 filed Jun. 15, 1999 the disclosures of which are incorporated herein by reference in their entirety, disclose polymerizable tooth making compositions. Kura et al in U.S. Pat. No. 5,989,031, the disclosure of which is incorporated herein by reference in its entirety, disclose injection molding of thermoplastic to form a tooth. According to DIN 13914, artificial teeth for producing dental prostheses must consist of several layers because of the desired similarity to natural teeth. Such multilayer teeth have previously been produced exclusively by a pressing process, wherein the differently dyed pressing masses are placed by hand in the pressing tool. The pressing of the teeth is very labor-intensive. The distribution of the layers put in place by hand is subject to irregularities. The excess amounts necessary for pressing lead to considerable burr formation at the separating plane of the mold halves. This makes subsequent processing necessary. Thus considerable production effort is connected to the production of conventional multilevel teeth, so that these teeth are relatively expensive.
The present invention is based on the problem of creating an artificial tooth constructed of several layers whose production can be largely automated and in which a reproducible arrangement of layers is guaranteed and, in particular, burr formation is also minimized, so that low production costs result.
The invention provides multiple part dental tooth molds and prosthetic teeth with an enamel layer having zones of uniform thickness. Prosthetic teeth in accordance with a preferred embodiment of the invention are readily articulable within sets and proportionally consistent within families. Prosthetic teeth in accordance with the invention are useful for making full and/or partial dentures, and as crowns, implant teeth and shade guides having prosthetic teeth thereon.
Tooth molds are used in the dental industry for the manufacture of artificial teeth. Refining steps include a final finish-polish step, which provides a mold of high-definition of the surface properties of the artificial tooth to be produced by molding tooth making material therein.
Dehoff et al in U.S. Pat. No. 5,452,219 (Case 1619) discloses a method for making a tooth mold. Erdle in Australia 124,083 disclose ceramic articles and material and method for coloring or shading the same. Saffir in U.S. Pat. No. 2,380,568 disclose artificial tooth. Kelly in U.S. Pat. No. 2,514,075 disclose artificial tooth. Erdle in U.S. Pat. No. 2,517,100 disclose method of forming ceramic articles and producing different colors or shades along different potions of the article. Budish in U.S. Pat. No. 2,643,455 disclose artificial teeth. Rydin in U.S. Pat. No. 2,677,150 disclose method in producing artificial teeth. Slack, Jr. in U.S. Pat. No. 2,678,470 disclose polymerizing method. Saffir in U.S. Pat. No. 3,126,429 disclose method of casting teeth having different colored layers. Connan in U.S. Pat. No. 3,218,711 disclose artificial teeth. Swinson in U.S. Pat. No. 3,861,044 teaches a method of fitting a tooth with a dental inlay. Heitlinger et al. in U.S. Pat. No. 4,324,546 disclose an apparatus and method for the manufacture of dentures. Tanaka in U.S. Pat. No. 4,392,829 disclose metal porcelain dental restoration and method of making. Faunce in U.S. Pat. No. 4,433,959 disclose composite laminate dental veneer containing color systems. White in U.S. Pat. No. 4,436,684 describes methods of making three dimension models and mold cavities of internal body structure.
Tanaka in U.S. Pat. No. 4,481,227 disclose method of coloring bakable porcelain dental restorations. Moermann et al. in U.S. Pat. No. 4,575,805 disclose a method and a apparatus for the fabrication of custom-shaped implants.
Duret et al. in U.S. Pat. No. 4,611,288 describe a system for taking an impression of a body region for the production of a prosthesis.
Moermann et al. in U.S. Pat. No. 4,615,678 teach a blank from which an implant can be machined by an apparatus of the type disclosed in U.S. Pat. No. 4,575,805. Miller in U.S. Pat. No. 4,617,159 disclose method of molding a dental shade sample. Amdur et al. in U.S. Pat. No. 4,645,454 disclose porcelain products and methods. Blair et al. in U.S. Pat. No. 4,650,418 disclose dental restoration shading. Duret et al. in U.S. Pat. Nos. 4,663,720 and 4,742,464 disclose a method of making a dental prosthesis. Watanabe et al. in U.S. Pat. No. 4,681,633 disclose high strength calcium phosphate glass ceramic materials. Corbett in U.S. Pat. No. 4,722,689 disclose coated temporary dental crowns. Brandestini et al. in U.S. Pat. No. 4,766,704 describe a method and apparatus for machining a custom-shaped dental restorative part from a blank of dental material in a single operation. Brandestini et al. in U.S. Pat. No. 4,837,732 teach a method of facilitating acquisition of data defining the three-dimensional shape of prepared teeth and their immediate vicinity.
Rotsaert in U.S. Pat. No. 4,970,032 disclose processes for the manufacture of artificial teeth and crowns. Grossman et al. in U.S. Pat. No. 5,089,306 disclose glazing dental constructs. Hasegawa et al. in U.S. Pat. No. 5,127,834 disclose artificial teeth and method for making them. Rotsaert in U.S. Pat. No. 5,151,044 disclose blanks for the manufacture of artificial teeth and crowns. Emmons in U.S. Pat. No. 5,308,243 disclose method and compositions for producing life-like dental porcelain restorations and dental porcelain restorations so produced. Oden in U.S. Pat. No. 5,342,201 disclose method of manufacturing ceramic artificial tooth restorations.
It is an object of the invention to provide artificial teeth with an enamel layer having zones of constant thickness.
It is an object of the invention to provide a family of prosthetic teeth, including a first tooth in a first set of teeth having a first overall labial length, and a first back length, and a second tooth in a second set of teeth having a second overall labial length, and a second back length, wherein the ratio of the first to the second overall labial length is substantially equal to the ratio of the first to the second back length.
It is an object of the invention to provide a prosthetic tooth including a tooth body having two generally symmetrical curved grooves between three curved ridges on the labial face of the body at the incisal end of the body, wherein the grooves are deepest at the incisal end and extend substantially from the incisal edge to at least about 15 percent of the overall tooth length.
It is an object of the invention to provide an image of at least a portion of at least one upper tooth and at least one lower tooth, each said tooth being from the same side of the same set of teeth, modifying initial data corresponding to the image to form modified data, molding modified prosthetic teeth in molds made using the modified data, whereby, during articulation the modified prosthetic teeth contact along a larger proportion of tooth surface than prosthetic teeth made in molds using the initial data.
Set of teeth as used herein refers to teeth to be used for the same individual, such as is a single denture whether full or partial.
Family of teeth as used herein refers to sets of teeth of different sizes and/or shades but having common shapes.
A process for producing an artificial tooth comprising: injection molding polymerizable material into a mold to form an outer external polymeric layer. Then injection molding polymerizable material into the mold to form an inner polymeric layer applied on the first external layer. Then injection molding polymerizable material into the mold to form a solid core applied on the inner external layer.
The problems of high mold pressure and limited tooth shading are solved according to the invention in that low pressure is use for injection and shading may be custom blended at the molding site.
The invention relies upon the recognition that a considerable savings in cost can be achieved by injection molding technology, since injection molding is done completely automatically and hence a reproducible arrangement of layers can be guaranteed. This may involve a multicomponent injection molding process, wherein the material components form layers inside the tooth body so that, by dying the individual material components differently the natural tooth appearance can be optimally approximated.
A prosthetic tooth having an enamel layer which has a zone of substantially constant thickness. This tooth is molded using a dental tooth mold part prepared by imaging a dental pattern of a prosthetic tooth shade layer and/or shader mold part outer surface, and forming the dental pattern in a mold by program directed milling.
The invention provides a family of prosthetic teeth, including a first tooth in a first set of teeth has a first overall labial length, and a first back length, and a second tooth in a second set of teeth has a second overall labial length, and a second back length. The ratio of the first overall labial length to the second overall labial length is substantially equal to the ratio of the first back length to the second back length. Preferably the first tooth has a first shade length and the second tooth has a second shade length and the ratio of the first shade length to the first overall labial length is substantially equal to the ratio of the second shade length to the second overall labial length.
The invention provides a prosthetic tooth including a tooth body having two generally symmetrical curved grooves between three curved ridges on the labial face of the body at the incisal end of the body. The grooves are deepest at the incisal end and extend substantially from the incisal edge to at least about 15 percent of the overall tooth length.
The invention provides a method of making readily articulable prosthetic teeth by displaying an image of at least a portion of at least one upper tooth and at least one lower tooth from the same side of the same set of teeth, then modifying initial data corresponding to the image to form modified data, molding readily articulable prosthetic teeth in molds made using the modified data, whereby, during articulation the readily articulable prosthetic teeth contact along a larger proportion of tooth surface than prosthetic teeth made in molds using the initial data.

Prosthetic teeth and method of making therefor


An end system (“first end system”) concluding that a bi-directional virtual circuit is operational if the other end system (at the other end of the virtual circuit) has determined that the virtual circuit is operable based on the loopback cells. In other words, the first end system may not send loopback cells, and instead rely on the determination of the other end system. As a result, the total number of loopback cells may be reduced on a network backbone.

1. Field of the Invention
The present invention relates to telecommunication networks, and more specifically to a method and apparatus for reducing overhead when using loopback cells for fault detection of bi-directional virtual circuits.
2. Related Art
Bi-directional virtual circuits are often provided to enable data transfers between two systems in a network. A bi-directional virtual circuit refers to a virtual circuit in which data traverses the same set of intermediate devices (forming the path) in both the directions. As an example, a virtual circuit provides communication between two end systems (e.g., edge routers or other devices interfacing directly with an ATM switch) in asynchronous transfer mode (ATM) networks, and the same intermediate switches provide the path between the two end systems in both directions.
Loopback cells are often used to detect faults in the path of virtual circuits. In a typical scenario, each end system ("source end system") sends a loopback cell ("loopback command") directed to the other end system (i.e., at the other end of the virtual circuit), and the other end system sends back the cell ("loopback acknowledgment") with potentially some acknowledgment information incorporated within the cell. The source end system determines the status of the path (including intermediate devices and connecting transmission lines) depending on whether the loopback response is received or not.
OAM (operation, administration and maintenance) cells (both commands and acknowledgment/responses) used in the context of ATM networks are examples of the loopback cells. Only some of the details of OAM are described here for conciseness. For further details on OAM, the reader is referred to ITU-T Recommendation I.610 entitled, "Series I: Integrated Services Digital Network—Maintenance principles B-ISDN operation and maintenance principles and functions", which is incorporated in its entirety herewith. At least in OAM related implementations, both end systems (at either end of a virtual circuit) independently check the status of the PVC.
One problem with such implementations is that the overhead on the components in the network due to resulting traffic (i.e., command and acknowledgment loopback cells) may be unacceptably high. The overhead may include use of bandwidth (which may otherwise be available for other applications) on the communication links and also buffering/processing overhead on all the devices in the virtual circuit path. Such overhead is particularly high on end systems which may need to process the cells more than other devices. The overhead may be unacceptable at least in that the corresponding end system implementations may not scale to large networks (employing a lot of end systems).
Accordingly, what is needed is a method and apparatus which reduces fault management related traffic (cells) when using loopback cells for fault detection of bi-directional virtual circuits.

Reducing overhead when using loopback cells for fault detection in bi-directional virtual circuits


A method and apparatus for handling a downlink control information indication for retransmission, the method receiving a downlink control information indication for retransmission of a hybrid automatic repeat request (HARQ) process; and if a transport block size in the downlink control information has changed compared with a transport block size associated with the HARQ process or a previous uplink grant for the HARQ process: handling the downlink control information indication for retransmission.

In the 3rd Generation Partnership Project Radio Access Network, Radio layer 2 and Radio layer 3 radio resources (RAN2) working groups, an uplink Hybrid Automatic Repeat Request (HARQ) entity is conceptually in charge of co-ordinating user equipment (UE) operation in order to provide data for uplink transmission as appropriate. At each transmission opportunity, the uplink HARQ process associated with that transmission opportunity may be instructed by the uplink HARQ entity to perform various actions, including a new data transmission, adaptive retransmission, non-adaptive retransmission or nothing.
An adaptive retransmission allows for different physical resources or parameters, signaled through downlink control information than for the most recent transmission of the same transport block. Conversely, non-adaptive retransmission is performed using the same physical resources as the most recent transmission for the same transport block but with a different redundancy version. New data transmissions and adaptive retransmissions have priority over non-adaptive retransmissions for the same transmission opportunity.
For adaptive retransmission, the Downlink Control Information (DCI) format 0 (DCI 0) is used to signal the retransmission. In some cases and for various reasons the UE may see a DCI 0 ordered adaptive retransmission where the transport block size has changed without a New Data Indicator (NDI) flag having been changed. This may be caused, for example, by a UE failing to detect a DCI 0 on the physical downlink control channel (PDCCH) which was transmitted by the Evolved Node B (eNB). Such missed detection is termed a false negative, and may occur due to poor or changing channel conditions, sudden interference and other variable conditions typically associated with wireless transmission channels. Further, the UE may, from time to time, detect a DCI 0 on the PDCCH which is not actually representative of a DCI 0 that was transmitted from the eNB. Such detection is termed a false positive and may interfere with normal UE operation.
Thus, in some situations, a UE may detect a DCI 0 addressed to the UE with a non-toggled NDI and with a different transport block size.

Method and system for handling of a transport block size change in an adaptive retransmit order


A method for performing dual mode imaging of a borehole determines a reference point in a geological formation in response to a resistivity measurement of the formation. The reference point is associated with a feature, such as a fracture, in the formation. A tilt angle of the feature is determined, with respect to the reference point, in response to the received electromagnetic signals from the formation. For example a time-of-flight, ranging operation may be performed or an attenuation and phase change of the received signals may be determined to image the feature.

Electromagnetic resistivity sensors are used in borehole drilling to image formation properties. Such sensors include small button electrodes that focus a current into the formation and, using Galvanic measurement principles (e.g., Ohm's law), image the surrounding formation based on received signals. Analysis of fracture orientation data from boreholes has determined that the boreholes may introduce an observational bias into the collected data such that formation fractures at small angles to the borehole are under-represented in the data. Accounting for such formation fractures may be important in evaluating the geology, mechanics, or hydraulics of a subsurface rock mass.

Dual mode electromagnetic imaging of a borehole


A composition forming a rubber roller and an imaging apparatus including the rubber roller are provided by the invention. A small amount of a nitrogen-containing compound is formed during the process of preparing the rubber roller without deterioration of image quality of images produced by an imaging apparatus. The roller rubber forming composition includes a base rubber; a vulcanizing agent; a vulcanizing accelerator; a conducting agent; and one of an acid anhydride, a zeolite, and a blend thereof.

1. Field of the Invention
The present invention relates to a composition for forming a roller rubber, a rubber roller made from the composition, and an imaging apparatus including the rubber roller. More specifically, the invention is directed to a composition for forming roller rubber having a decreased amount of a nitrogen-containing compound without a decrease in quality of images produced by an imaging apparatus. The invention is also directed to an imaging apparatus including the rubber roller.
2. Description of the Related Art
FIG. 1 is a schematic view of a conventional electrophotographic imaging apparatus. The conventional electrophotographic imaging apparatus illustrated in FIG. 1 operates as follows. First, a photoconductive drum 11 is charged by a charging apparatus 16, and then an electrostatic latent image is formed on the photoconductive drum 11 by image exposure through a laser scanning unit (LSU) 18. A toner 14 is provided to a development roller 12 by a toner supply roller 13. The toner 14 provided to the development roller 12 is formed in a thin film having a uniform thickness by a toner layer controlling device 15 and is charged. After passing the toner layer controlling device 15, the toner 14 is used to develop the electrostatic latent image formed on the photoconductive drum 11, and the developed image is transferred onto a sheet of paper by a transfer roller 18 and fixed by a fixing device (not shown.) In addition, toner 14 remaining on the photoconductive drum 11 after the transferring process is removed by a cleaning blade 17.
In the conventional electrophotographic imaging apparatus illustrated in FIG. 1, the development roller 12 and the charging apparatus 16 comprise a rubber roller. FIG. 2 illustrates sectional and perspective views of the conventional rubber roller used in the conventional electrophotographic imaging apparatus of FIG. 1.
Referring to FIG. 2, the conventional rubber roller includes a shaft 32 and a rubber layer 31. Conventional rubber rollers can be categorized into ion conductive type rubber rollers and electron conductive type rubber rollers. Ion conductive type rubber rollers are formed of a rubber with low volume resistance, such as hydrin rubber. However, due to the high resistance of the rubber itself, it is difficult to manufacture low resistant rollers using the rubber alone, and thus a conductive additive, such as a conductive polymer material or ion conducting agent, is added to produce a conductive rubber. Electron conductive type rubber rollers can be manufactured by adding carbon black or metal powder, such as copper, to rubber rollers to provide conductivity thereto.
In ion conductive type rubber rollers, the conductive rubber used is expensive and the resistance varies according to surrounding conditions due to obtaining conductivity by ion dissociation. On the other hand, electron conductive type rubber rollers do not use such expensive conductive rubber and have a constant resistance independent of factors such as temperature and humidity in the surrounding environment.
Meanwhile, when rubber rollers formed of NBR, ECO, SBR or EPDM, are produced by sulfur crosslinking, a large amount of volatile organic compounds (VOCs) are formed from side products produced by the decomposition of vulcanizing agents, accelerators, and other additives. Therefore, the formed VOCs may damage an organic photoconductive drum (OPC) contacting a development roller of a electrophotographic imaging apparatus, thereby causing image defects.
Meanwhile, in the crosslinking process of such rubber rollers, a vulcanizing agent, such as sulfur, and a vulcanizing accelerator, such as a thiozole-based compound, a thiuram-based compound, or a sulfonamide-based compound are used. At this time, amine or amide-based nitrogen-containing compounds are formed by the decomposition of the vulcanizing accelerator under vulcanizing conditions including high temperature and high pressure. Nitrogen-containing compounds have an unpleasant odor and cause cracks in OPC coating layers formed of polycarbonate resin. In addition, the amount of total volatile organic compounds (TVOC) is increased which can be harmful.
Accordingly, there is a need to develop a rubber roller which can be produced without formation of VOCs.

Roller rubber forming composition, rubber roller including the same, and imaging apparatus including the rubber roller


A desensitizing ink for printing by wet or dry offset, flexographic or typographic printing is disclosed and claimed. This ink contains at least one desensitizing agent, at least one ink binder which is polymerizable or crosslinkable by UV light or electron beam radiations and, if necessary, an initiator system. Thus, the drying time of the printings is greatly reduced. The ink is free from vaporizable ink solvents.

Desensitizing inks are generally known to the one skilled in the art for the preparation of passivated regions or areas of chemically self-copying sets comprising at least two superimposed sheets, generally of paper, whose contacting faces are each coated with a layer. Usually, the top sheet comprises on its back surface a nucleophilic layer, and the underlying sheet has an electrophilic layer on its upper surface. A local pressure applied to the overlaying sheet produces a chromogenic reaction between the sheets so that the underlying sheet reproduces said local pressure. Multilayer sets or stacks are also known, based on the same principle.
Several examples of such inks have already been described; a most recent development made by the Applicants is disclosed in U.S. Pat. No. 5,035,743, patented Jul. 30, 1991, and in the corresponding European Patent No. EP-B1-0,333, 645. The whole disclosure of said U.S. and European patents is incorporated herein by reference. The disclosure of these patents explains in detail the chemistry of desensitizing and also the above mentioned four printing techniques. Thus, the principles of application and function of desensitizing inks will not be repeated in this paper.
A serious problem arising during the printing with desensitizing ink is the drying of the printings after the printing process. The drying time is of very high importance since, if the drying speed is too low, there is a set-off of the printed sheets which are laid down on stacks at the outlet of the printing press, or a set-off between following layers if the printed paper is wound on rolls.
It has already been tried to speed up the drying by curing the inks under the influence of energetic radiation. It should be explained here that desensitizing inks contain non-volatile liquids, and that the drying of the printings is mainly due to absorption of said liquids in the paper. To the contrary, a "drying" by radiation is effected by rapid polymerisation of polymerizable components of the ink, and this "drying" which is so called in the printing art, is in reality a radiation initiated chemical hardening or crosslinking. However, the substances and compositions which must be added to a conventional ink in order to render them curable by exposure to rays, make them inoperative since a strong diminution or a total absence of desensitizing power has been observed.
Thus, Japanese Patent Application No. 77/91,010 of Jul. 29, 1977, referenced in Chemical Abstracts Vol. 91, No. 25 of Dec. 17, 1979, reference 212,738a, discloses a desensitizing ink for pressure sensitive copying papers containing photosensitive binders and, as the desensitizing agent, a propylene glycol diglycidyl ether diacrylate. However, this compound is also polymerized under the conditions of ink polymerisation and does not show the excellent desensitizing power of Applicants' inks according to U.S. Pat. No. 5,035,743 as explained in that reference. Furthermore, that desensitizing agent is even free from nucleophilic hydroxyl groups.
U.S. Pat. No. 4,073,969 discloses a new method to desensitize the color developer coating. This method comprises covering the color developer with a cured film thereby to desensitize the color developer. In other words, the principle of that known method is to separate the color developer from the color former by a photocured film.

Curable desensitizing ink for the printing of self-copying sheets


A security method for theft prone areas of a retail store which alerts store employees of possible theft situations. The security method includes controlling an RFID label reader adjacent an entrance to a monitored area to determine entry of an item bearing an RFID label into the monitored area and departure of the item from the monitored area, sensing entry of the item into the monitored area, and issuing an alert to store personnel.

The present invention relates to security systems for stores and more specifically to a security method for theft prone areas of a retail store.
Certain areas of retail stores are particularly prone to shoplifting. These areas include restrooms and fitting rooms. By carrying merchandise into those rooms, shoppers can conceal merchandise with the intent not to pay for it. Many stores post signs indicating that merchandise belonging to the store may not be carried into restrooms. Stores often allow only a restricted number of items to be carried into a fitting room.
Current solutions involve assigning employees to monitor fitting rooms. However, the employees are sometimes called away from their stations to wait on other customers. This leaves the fitting rooms unsupervised and vulnerable to shoplifting.
Therefore, it would be desirable to provide an alternative security method for theft prone areas of a retail store.

Security method for theft prone areas of a retail store


A projection type imaging display system utilizing a liquid crystal panel projector. The zoom position of a projection lens is detected as an indicator of the aspect ratio of the main image being projected. Based on the zoom position, the position of an information display signal superimposed upon the main image is adjusted relative to the position of the main image, so that the information display signal is displayed on the main image no matter what the aspect ratio of the main image is.

1. Field of the Invention
The present invention relates to an image projection device capable of super-imposing an on-screen information display onto the main image being projected. In particular, the invention provides for an image projecting apparatus including an on-screen displaying circuit capable of adjusting a location of a superimposed image in response to varying aspect ratios of the main image being projected.
2. Description of the Related Art
A liquid crystal projector has lately attracted considerable attention. To obtain a large-sized image, a halogen lamp or the like emits light from the rear of a liquid crystal panel. Thereby, an image on the liquid crystal display is enlarged and projected onto a front screen through a projection lens. The advantages this structure is that the liquid crystal display is small and light, yet the size of a picture image can be easily enlarged by the scale factor of the projection lens. Therefore, a television apparatus capable of obtaining a large-sized picture image from a small and light weight device can be developed.
Since the liquid crystal projector is a kind of television receiver, a receiving circuit has been developed which is capable of displaying additional information such as a channel display, an image menu display and a picture in picture display.
FIG. 10 is a block diagram showing an on-screen displaying circuit in, use. The circuit illustrates a circuit formation which determines a display position of an on-screen signal in the vertical direction when the on-screen signal is displayed on a television picture plane. In FIG. 10, a counter 31 is operated by inputting a horizontal synchronizing signal HD into a display position circuit as a clock pulse, and using a vertical synchronizing signal VD as a reset pulse, a display position timing pulse is produced which corresponds to a display position of the on-screen signal. Input ends d and e of a switch 32 are selectively changed over using this display position timing pulse, so that an output video signal in which an on-screen signal is superimposed will be obtained and supplied to a displaying device 33 composed of a liquid crystal panel and a cathode ray tube. The image on which the on-screen information is superimposed is displayed by the displaying device 33. In a projecting-type television receiver, the image displayed on the displaying device 33 is further enlarged and projected on a screen 35 through a projection lens 34.
FIG. 11 shows a timing of a signal for each portion of FIG. 10. In FIG. 11, (a) and (b) represent a horizontal synchronizing signal HD and a vertical synchronizing signal VD supplied to the counter 31, respectively. Also, (c) represents counter output (that is, a display position timing pulse) which is output when a predetermined number (the number of n) of the horizontal synchronizing signals HD are counted after the counter 31 is reset by a trailing edge of the vertical synchronizing signal VD. (d) and (e) represent a video signal and an on-screen signal supplied to two input ends d and e of the switch 32, respectively. A video signal on which an on-screen signal is selectively superimposed, as shown in (f), is output from the switch 32.
In our highly oriented information age, it has been desired to increase the aspect ratio of video software from 16:9, as represented Hi-Vision broadcast size, a Cinema Scope size or a vista size, to an aspect ratio of 16:12 (=4:3). In current video software, for example as shown in FIGS. 12(a) and 12(b), if a zoom ratio of a projection lens of a liquid crystal projector is changed, an image having the ratio 16:9 can be projected to fill the screen 35. FIG. 12(a) represents a case in which a liquid crystal picture image having the ratio 16:12 is enlarged and displayed on the screen 35, also having the ratio 16:12. FIG. 12(b) represents a case in which a picture image having the ratio 16:9, such as a Hi-Vision broadcast, is displayed on the liquid crystal picture plane having the aspect ratio 16:12 and enlarged and displayed on the screen 35 having the ratio 16:9.
In this case, as shown in the timing chart of FIG. 11; a display position of an on-screen signal is determined regardless of the contents of a video software. Therefore, as shown in FIG. 13(a), there is no problem in the case when an on-screen display is superimposed onto the liquid crystal picture image having the aspect ratio 16:12 and enlarged and displayed on the screen 35 having the same aspect ratio 16:12. However, as shown in FIG. 13(b), a part of the superimposed on-screen display will be projected off of the projection screen 35 when a picture image having the aspect ratio 16:9 is displayed on the liquid crystal picture plane having the aspect ratio 16:12 and enlarged and displayed on the screen 35 having the aspect ratio 16:9. As a result, not all of the superimposed on-screen information will be displayed proper.
The size of a picture image can be easily changed by a zoom ratio of a projection lens in a projecting-type image displaying apparatus, such as a liquid crystal projector. However, it is inconvenient that a superimposed on-screen display goes beyond a projection screen as the size of a picture image is determined in accordance with the video software.

On-screen displaying apparatus having zoom function


A padlock protector to protect a padlock with its shackle through the staple of a hasp, comprising a three dimensional housing to receive the padlock therein, a closure member having an imperforate and integrally joined sealing structure around its periphery to prevent moisture from entering the housing from around the peripheral edge when the closure member is in its closed position, apertures to receive either a vertically or horizontally extending staple of a hasp or other lockable loop member through a wall of either the closure member or the housing to enter the cavity of the housing for the shackle of the padlock to lock, such staple receiving apertures having closure flaps, such closure flaps being integrally joined to the wall through which such apertures extend by an integral flexible hinge along a portion of the peripheral edge of such closure flaps and by an integral break-away web of thin cross-section along the remaining portion of such peripheral edge of the closure flaps. The housing and closure member are preferably transparent, and made of a shape retaining but compressible and somewhat flexible material.

This invention relates to a protector for padlocks which will shield them from moisture such as rain and snow and from any other materials which may reach the lock if not covered or shielded from such contact. In particular, it relates to a protective enclosure which may also double as the package in which the padlock is offered for sale.
Prior art devices of this kind of which the inventor is aware include those disclosed in the following United States patents.
U.S. Pat. No. 5,003,795 discloses a lock protector comprising a notebook cover type of device, comprising a flat front cover and a flat back cover joined together along one edge by a flexible hinge, having top, bottom and side margins which are provided with cooperative fastening means such as hook and loop Velcro type fasteners or adhesive material which will hold the notebook cover type of device closed around the edges when the covers are folded together. A slot is provided in the back cover to receive the staple of a hasp locking member therethrough, which the shackle of a padlock is then placed through and locked. When the padlock is placed in position to lay flat against the back cover, the marginal edges around the front cover can then be pressed inwardly far enough to engage the cooperative fastening means around the marginal edges of the back cover while the interior portions of the front and back covers bulge out to accommodate the padlock sandwiched therebetween. Various modifications are disclosed including one having a pouch located below a vertical slot for the padlock to drop into, and a flap to cover the pouch, the vertical slot bisecting the hinge line between the flap and the panel on which the pouch is mounted.
U.S. Pat. No. 4,882,918 discloses a padlock cover having a retainer member to prevent movement of the body portion of the padlock within such cover It is particularly adapted for padlocks having a cylindrical combination unlocking mechanism.
U.S. Pat. No. 4,286,445 discloses a padlock protective cover comprising an enclosure having the peripheral configuration and dimension corresponding to that of the body portion of a padlock, and opening means for access to the key slot of the padlock o its other unlocking mechanism.
U.S. Pat. No. 4,033,156 discloses a cover for a padlock comprising a box-like enclosure having an opening through a side wall to receive the hinged arms of a hasp type of locking member, the locking end being received in the box with the padlock also being received in the box.
U.S. Pat. No. 3,458,113 discloses a plastic container having a closure lid secured to the container along one side edge by a pair of spaced apart integrally formed hinges.
U.S. Pat. No. 3,240,375 discloses a shipping and display container having a cover secured to the container along a side edge by a hinge which extends part way along the side edge, the display container having a pair of lugs on the hinged side to prevent the cover from pivoting one hundred and eighty degrees from the closed position to an opened position in which the cover would be substantially in line horizontally with the container.
U.S. Pat. No. 1,220,941 discloses a protector for padlocks comprising a metal channel type of cover, having a solid forwardly facing wall and solid side walls, an open rearwardly facing wall and an open bottom wall, the forwardly facing wall tapering toward the rearwardly facing open wall as it extends toward its upper edge, the upper edge being hinged to a plate which is secured to a door frame by screws. The hinged channel type of cover can be pivoted upwardly for access to a lock member and a padlock connected therein.
U.S. Pat. No. 1,136,582 discloses a lock shield in the form of a hood which is connected at its upper edge by a hinge to a hinge plate secured to a door or wall by screws, the hood being pivotable from a closed position in which it covers a padlock and lock member to an open position wherein the padlock and lock member are exposed for access thereto.
U.S. Pat. No. 416,433 discloses a padlock cover which is also in the form of a hood having its upper edge hinged to securing means which secures the cover device to a door or wall, the device covering a padlock and lock member when pivoted downwardly and uncovering when pivoted upwardly.
U.S. Pat. No. 256,902 discloses a padlock cover in the form of an ovular box having curved side walls, hinged to a hinge plate along the upper end, the hinge plate being securable to a door or wall by screws, the ovular box being pivotable between a closed position and an open position, covering the staple of a hasp type lock and shackle of a padlock through the staple when in the closed position and giving access thereto when in the open position.
The protector for padlocks in accordance with the present invention is an improvement over the prior art devices in this field. It provides a housing having a three dimensional cavity to receive a padlock, a closure member to close the cavity, a vertically extending aperture through the closure member to receive the staple of a hasp which extends vertically for the shackle of the padlock to extend through and lock, a horizontally extending aperture to receive the staple of a hasp which may extend horizontally, an integrally formed flexible hinge connecting the closure member to the housing, and an overlapping peripheral connecting member integrally formed around the peripheral edge of the closure member having an imperforate outwardly facing surface and an inwardly facing interlocking peripheral recess to receive a corresponding interlocking peripheral rib around the peripheral edge of the housing. When the closure member is in its closed position, the interlocking peripheral rib of the housing is received in the interlocking peripheral recess of the closure member to releasably interlock the closure member to the housing.
The outwardly facing imperforate surface of the integrally formed overlapping connecting member around the peripheral edge of the closure member provides a positive imperforate seal against moisture to prevent any moisture from entering the cavity of the housing around any part of its peripheral edge when the closure member is in its closed position.
To prevent moisture from entering the housing through the vertical and horizontal elongated apertures for the staple of a hasp, each is provided with a closure flap having one edge integrally joined to the closure member to provide an imperforate flexible hinge.
In the event any moisture enters the cavity of the housing when a staple of a hasp is extending through one of the apertures, a drain aperture is provided through the closure member below such staple receiving aperture having a drain aperture closure flap which in its open position extends inwardly of the cavity and inclined upwardly from an integrally joined flexible hinge along the bottom edge of the drain aperture closure flap which joins it to the closure member of the housing.
The staple receiving apertures are shown and described in this specification and drawings as being through the closure member. This invention encompasses various modifications which can be readily understood without unduly lengthening the specification with repetitive description and drawings. For example, the staple receiving apertures and the drain aperture with their corresponding closure flaps may be provided through the otherwise imperforate floor or outwardly facing bottom wall of the three dimensional housing.
The padlock protector in accordance with the present invention has the additional advantage of being able to double as the package in which a new padlock is shipped and sold. The housing and closure member are preferably transparent so the padlock inside is readily visible. The staple receiving apertures and drain aperture have their respective closure flaps originally sealed shut by imperforate integrally joined peripheral webs of thin cross-section. The webs will break away when separating pressure is applied to the closure flaps along respective portions of the break-away webs.
Further advantages of the padlock protector in accordance with the present invention will become apparent from the more detailed description which follows.


Techniques for improving manufacturing process control based on inspection of manufactured items at intermediate process steps, based on clustering and binning of defect data. Additionally, the using the defect data produced by inspection machines to improve manufacturing process control specifically relating to semiconductor manufacturing process control. Examples described here relate specifically to semiconductor wafers, but may be generalized to any manufacturing process.

The key to profitability in the semiconductor industry is yield management. Virtually any integrated circuit manufacturer would be profitable if they could have a manufacturing process that had a 100% yield, and certainly would be unprofitable if the yield were below 20%. To obtain a high yield rate is an on-going task of manufacturers that requires continuous monitoring and identifying production problems that are adversely impacting yield.
Typically, a semiconductor wafer may have a very large number of defects (e.g., more than 1000) which may have resulted from a great number of causations. Because, in general, the number of defects is very high, it is extremely time-consuming and expensive for an operator to examine each and every defect, and for that reason such a thorough examination of a wafer is infrequently performed.
In general there are two broad categories that cause yield reduction in the manufacturing process: handling problems; and process problems. Grouped defects typically have a common causation, some of the well known causations are chemical smears, grain, haze, microscoring, wand marks, brush marks, rail marks, impact marks, hot spots, shower patterns, exposure shutter patterns, doughnut patterns, poorly or unevenly developed layers on the die, over etching, under etching, thermal variations, etc.
Defects, no matter what the cause, have their own signatures which can be used to identify the causal mechanism of that particular defect, or defect group or pattern. Thus, it has also been determined that defects having the same causal relationship are likely to be statistically similar in their properties, such as location, proximity on the wafer, size and shape, as well as the shape of the defect pattern or cluster of defects resulting from the same causal mechanism.
Typically, an assessment of the state of a manufacturing process involves:
1. Selection of the set of manufactured articles to inspect; PA1 2. Inspection of the selected article(s); PA1 3. Selection of defects to review--all defects detected, or a selected sample; PA1 4. Review of selected defects; PA1 5. Analysis of inspection and review results; and PA1 6. Determination of process control action to be taken. (This may include a decision of which articles to inspect next.) PA1 1. Defects to be reviewed are selected (This may be all of the defects detected during inspection, or a manually or automatically selected sample); PA1 2. The operator views the defect, or an image of the defect using a microscope, scanning electron microscope (SEM), etc.; and PA1 3. The operator assigns a defect type classification, typically a numerical code, to the defect based on preselected criteria. PA1 1. The operator manually searches for clusters in the set of defect data (i.e., on a map showing all defects on a particular wafer--a wafer map); PA1 2. The operator manually selects some defects from each cluster; and PA1 3. Based on the types of defects identified in the cluster, a type classification is assigned to the cluster, and to all defects in the cluster. PA1 1. The number of defects detected during inspection that do not significantly affect yield can overwhelm the review process. PA1 2. Reviewing all the defects detected is too expensive, both in the amount of time and in the amount of human labor required. This leads one to review a sample of the detected defects. Manual selection of samples is highly subjective (i.e., not random.) PA1 3. A large delay while manually reviewing defects in a manufacturing process is undesirable, having one or all of the following negative effects: PA1 4. Some causal mechanisms produce a single defect event that is wrongly detected as a group of defect events having a common causal mechanism by an inspection machine. SPC that uses this defect count as an input is adversely affected. PA1 5. Each defect cluster is assumed to be caused by a single causality. However, an accurate estimate of the number of defects in a cluster, and by implication the total number of clustered defects, is impractical to obtain manually. Without this correction to the defect count, SPC decisions will be based on an incorrect defect count. For example, in semiconductor processing, a radical increase in the number of detected defects on a small number of chips on a single wafer is not significant for SPC purposes, because such excursions do not significantly affect yield. PA1 6. The inspection tool makes numerous measurements of defect properties, the results of which are not generally available during manual defect review. Manual cluster classification accuracy is therefore less than optimal. PA1 7. The results of repeating defect detection may be skewed by the presence of clusters. PA1 8. The results of defect source analysis may be skewed by defect events that cover more than one inspected article. PA1 9. The review process does not take into account information previously acquired during inspection. Review typically continues until a specific number of defects, or the entire set of defects, have been reviewed.
In semiconductor manufacturing, integrated circuit inspection is typically performed between selected process steps. These inspections also are performed automatically with a machine designed specifically for this task with those machines typically performing either optical inspections or electrical tests. The meaning of inspection in this instance is the detection of observed differences between the expected product and the actual product either in appearance or electrical performance. The principle output of an inspection machine is typically the number of detected defects, a list of defect locations, and some measured properties of each defect.
Defects detected are often much larger than the detection system resolution used by the inspection system, but are usually reported in terms of the detection system resolution. A single defect event may cover an area many orders of magnitude larger than the inspection system resolution. As a result, a single defect event may be detected as multiple defects (e.g., a scratch may have several line segments that make up the total scratch). Thus, if the defect events are misidentified or miscounted there will be a distortion of the assessment of the state of the process that resulted in the defects, leading to incorrect process control decisions to correct the source of the defects.
After detection, defects are often reviewed manually with defect review being a process of assigning defect classification types to detected defects. Review strategies may vary, but in general that review proceeds as follows:
Since it is generally believed that a high degree of spatial correlation among a group of defects usually indicates a common defect causality, manual clustering is occasionally used during review:
Inspection and review data are typically analyzed in a number of ways. For example, correlation studies of final manufacturing yield versus each defect type are performed in order to prioritize the importance of defect types. Based significantly on this analysis, it may be determined that some defect types do not detract from yield. In other words, if one is using defect count as a Statistical Process Control (SPC) parameter, these defect types should not be included in the defect count.
Correlation studies of defect locations on a given wafer inspected at one step in the manufacturing process may be performed against the inspection results for the same wafer at a different process step, in order to determine the process step that is the source of particular defects or defect types. Identification of the processing step that is the source of a defect is a necessary condition for eliminating that source of the defects. Correlation studies of defects on one die may also be compared against other dies to identify repeating defects.
There are a number of problems with the prior art approach outlined above. Some of those problems are:
a. A smaller number of items will be inspected (because there is insufficient review capacity), giving a less accurate assessment of the state of the process, or PA2 b. A smaller percentage of defects detected will be reviewed, giving an assessment of the process state that may be skewed by bias in the manual sample selection, or PA2 c. The manufacturing process must be slowed down--which is generally unacceptable.
It would prove very beneficial if group defects could be placed into certain meaningful cluster approximations of those groups with each cluster having a related causality which would make defect data much more manageable. Then it would be even more beneficial if that more manageable cluster defect data could be processed automatically to identify corrective actions necessary to reduce the number of defect groups, and therefore total number of defects, that occur in later production runs. The present invention provide such a system.

Detecting groups of defects in semiconductor feature space