isc

On Optimal Control of Discounted Cost Infinite-Horizon Markov Decision Processes Under Local State Information Structures. (arXiv:2005.03169v1 [eess.SY])

This paper investigates a class of optimal control problems associated with Markov processes with local state information. The decision-maker has only local access to a subset of a state vector information as often encountered in decentralized control problems in multi-agent systems. Under this information structure, part of the state vector cannot be observed. We leverage ab initio principles and find a new form of Bellman equations to characterize the optimal policies of the control problem under local information structures. The dynamic programming solutions feature a mixture of dynamics associated unobservable state components and the local state-feedback policy based on the observable local information. We further characterize the optimal local-state feedback policy using linear programming methods. To reduce the computational complexity of the optimal policy, we propose an approximate algorithm based on virtual beliefs to find a sub-optimal policy. We show the performance bounds on the sub-optimal solution and corroborate the results with numerical case studies.




isc

Let's Discuss Memoization, or Should I Say Memoisation

“In computing, memoization or memoisation is an optimization technique used primarily to speed up computer programs by storing the results of expensive function calls and returning the cached result when the same inputs occur again” — Wikipedia article on memoization

I've written a two part article in Memoization in JavaScript. The first part explains the concept with basic implementation in JavaScript code. It details a way to apply the technique on function calls. It is generic to handle most JavaScript functions.




isc

DeVos’ rules bolster rights of students accused of sexual misconduct

By Erica L. Green The New York Times Company…



  • Nation & World

isc

The Spokane County Sheriff's Office has discretely acquired technology that enables them to bypass phone passwords

Cops are hackers now, too.…



  • News/Local News

isc

Combinatorial synthesis of libraries of macrocyclic compounds useful in drug discovery

A library of macrocyclic compounds of the formula (I) where part (A) is a bivalent radical, a —(CH2)y— bivalent radical or a covalent bond;where part (B) is a bivalent radical, a —(CH2)z— bivalent radical, or a covalent bond;where part (C) is a bivalent radical, a —(CH2)t— bivalent radical, or a covalent bond; andwhere part (T) is a —Y-L-Z— radical wherein Y is CH2 or CO, Z is NH or O and L is a bivalent radical. These compounds are useful for carrying out screening assays or as intermediates for the synthesis of other compounds of pharmaceutical interest. A process for the preparation of these compounds in a combinatorial manner, is also disclosed.




isc

Generating action tuples in response to discerned leads

Methods and arrangements for analyzing and responding to communications data. Telecom data are input, as are social network data. The telecom data and social network data are analyzed, and action tuples representing opportunistic leads are generated based on the analyzed telecom data and social network data.




isc

Process for preparing a methylene-bridged biscyclopentadienyl compound

The present invention relates to a process for preparing a methylene-bridged biscyclopentadienyl compound having the formula I ##STR1##where L are, independently of one another, identical or different and are each a cyclopentadienyl group, by reacting one or two cyclopentadienyl compounds LH with formaldehyde in monomeric, oligomeric or polymeric form or formaldehyde-generating reagents in the presence of at least one base and at least one phase transfer catalyst.




isc

Recursive type-IV discrete cosine transform system

A recursive type-IV discrete cosine transform system includes a first permutation device, a recursive type-III discrete cosine/sine transform device, a cosine/sine factor generation device, a recursive type-II discrete cosine/sine transform device, a second permutation device. The first permutation device performs two-dimensional order permutation operation on N digital signals for generating N two-dimensional first temporal signals. The recursive type-III discrete cosine/sine transform device repeats a type-III discrete cosine/sine transform for generating second temporal signals. The cosine/sine factor generation device sequentially performs cosine/sine factor multiplication and corresponding addition operations for generating third temporal signals. The recursive type-II discrete cosine/sine transform device repeats a type-II discrete cosine/sine transform for generating fourth temporal signals. The second permutation device performs a one-dimensional order permutation operation for generating N one-dimensional output signals. The N one-dimensional output signals are obtained by performing a type-IV discrete cosine transform on the N digital input signals.




isc

Distributed processing system and method for discrete logarithm calculation

Distributed processing system and method for discrete logarithm calculation. The speed and resource efficiency of discrete logarithm calculation may be improved by allowing a plurality of operation agents to distributively process an operation of generating a modulo multiplication auxiliary table, an operation of generating a pre-calculation table, and an operation of searching for an answer by applying an iterated function for discrete logarithm calculation in a discrete logarithm calculation operation using the pre-calculation table.




isc

System and method for detecting accidental peripheral device disconnection

A detection device for detecting the manner in which a peripheral device is removed from an electronic device is proposed. The detection device can be on the peripheral device or the electronic device and detects whether the peripheral device was removed in a manner that indicates the removal was intentional or unintentional.




isc

Acidic viscoelastic surfactant based cleaning compositions comprising glutamic acid diacetate

Acidic viscoelastic cleaning compositions are disclosed which use non polymer thickening agents. According to the invention, cleaning compositions have been developed using viscoelastic surfactants in acidic cleaning formulations. These provide the dual benefit of thickening as well as an additional cleaning, thereby improving performance. Applicants have also identified several pseudo linking agents which when, used with viscoelastic surfactants provide enhanced viscoelasticity and cleaning.




isc

Automatic disclosure detection

A method of detecting pre-determined phrases to determine compliance quality is provided. The method includes determining whether at least one of an event or a precursor event has occurred based on a comparison between pre-determined phrases and a communication between a sender and a recipient in a communications network, and rating the recipient based on the presence of the pre-determined phrases associated with the event or the presence of the pre-determined phrases associated with the precursor event in the communication.




isc

Method to publish remote management services over link local network for zero-touch discovery, provisioning and management

A system, method, and computer-readable medium are disclosed for realizing server management functionalities in the absence of a routable Internet Protocol (IP) network address of a remote access controller (RAC). A first device, which is operatively coupled to a link-local network, generates a Multicast Domain Name System (mDNS) IP multicast query message, which it then sends to a second device on the link-local network. In response, the second device, which comprises a RAC, returns its link-local IP address to the first device.




isc

Adjustment of the number of task control blocks allocated for discard scans

A controller receives a request to perform a release space operation. A determination is made that a new discard scan has to be performed on a cache, in response to the received request to perform the release space operation. A determination is made as to how many task control blocks are to be allocated to the perform the new discard scan, based on how many task control blocks have already been allocated for performing one or more discard scans that are already in progress.




isc

Discarding sensitive data from persistent point-in-time image

A network storage server implements a method to discard sensitive data from a Persistent Point-In-Time Image (PPI). The server first efficiently identifies a dataset containing the sensitive data from a plurality of datasets managed by the PPI. Each of the plurality of datasets is read-only and encrypted with a first encryption key. The server then decrypts each of the plurality of datasets, except the dataset containing the sensitive data, with the first encryption key. The decrypted datasets are re-encrypted with a second encryption key, and copied to a storage structure. Afterward, the first encryption key is shredded.




isc

Spinning disc centrifuge rotor

The spinning disc centrifuge rotor includes a sample holder formed from a cylindrical disc body and a cover plate that are made from a transparent material, such as polycarbonate. The disc-shaped body has two concentric or coaxial recesses defined therein. The first recess forms a cylindrical well or sample chamber for receiving a generally cylindrical rock sample. The second recess has a larger diameter than the first recess, and is shallower, forming a fluid collection area above the sample well, the second recess forming an annular ring extending around the top edge or rim of the sample well. An O-ring snugly within the outer wall of the second recess and forms a seal between the cover plate and the floor of the second recess, preventing fluid leakage. A rotor shaft extends from the bottom face of the cylindrical disc.




isc

Method and apparatus for removal of tars or resins from a scrubber liquid using a centrifuge with a discharge chamber scraper

The invention is a method of processing tarry or resinous liquids. Tarry liquids include wet scrubber liquids containing tars and chars derived from gasification, pyrolysis or drying of biomass. Resinous liquids include those derived from processing coniferous biomass. Tarry or resinous liquid is processed by a horizontal axis centrifuge having a discharge chamber containing a scraper to prevent centrifuge clogging or fouling. The removed tar and char can be used as solid fuel or recycled to the gasification or pyrolysis process. Polymers, for instance cationic polymers, can be added to the tarry or resin containing liquid prior to centrifugation to assist in solids/liquids separation. Removed resin can be recycled for further use. Tar, char or resin depleted wet scrubber liquid can be recycled for further use or more easily treated prior to disposal.




isc

Counter-current multistage fischer tropsch reactor systems

The invention discloses an improved multistage fischer tropsch process scheme for the production of hydrocarbon fuels comprising feeding gaseous phase syngas and liquid stream hydrocarbons in a counter current manner such as herein described into the reaction vessel at a number of stages containing reaction catalysts; wherein fresh syngas enters into the stage where the product liquid stream leaves and the fresh liquid stream enters into the stage where the unreacted syngas leaves; wherein further the temperature of each stage can be controlled independently. More particularly the invention relates to improving the heat release in different reactors, product selectivity and reactor productivity of FT reactors.




isc

High-speed stop in Fischer-Tropsch process

The present invention pertains to a process for carrying out a high-speed stop in a Fischer-Tropsch process which comprises providing a feed to a fixed bed reactor comprising a Fischer-Tropsch catalyst, the reactor being at reaction temperature and pressure, and withdrawing an effluent from the reactor, wherein the high-speed stop is effected by blocking provision of feed to the reactor and simultaneously blocking the withdrawal of effluent from the reactor.




isc

Fischer-Tropsch catalysts

A method of producing an alumina-supported catalyst for use in a Fischer-Tropsch synthesis reaction, which comprises: calcining an initial γ-alumina support material at a temperature of at least 550° C. to produce a modified alumina support material; impregnating the modified alumina support material with a source cobalt; calcining the impregnated support material at a temperature of 700° C. to 1200° C., and activating the catalyst.




isc

Method for processing fischer-tropsch off-gas

A method for producing a gas comprising at least 80 vol % carbon monoxide from a Fischer-Tropsch off-gas comprises: (1) feeding Fischer-Tropsch off-gas through a column comprising an adsorbent bed at high pressure and discharging effluent; (2) reducing the pressure in the column and the bed slightly; (3) rinsing the column and the adsorbent bed with methane or a mixture of methane and carbon dioxide; (4) reducing the pressure of the column and adsorbent bed to a low pressure; (5) rinsing the column and adsorbent bed with a mixture of hydrogen and nitrogen; (6) pressurizing the column and adsorbent bed to a high pressure using a mixture of hydrogen and nitrogen. The product stream obtained in step (3) comprising at least 80 vol % carbon monoxide can be sent as feed to a Fischer-Tropsch reaction. In an embodiment, a gas comprising at least 80 vol % hydrogen is also produced.




isc

Preparation of iron/carbon nanocomposite catalysts for Fischer-Tropsch synthesis reaction and related production of liquid hydrocarbons

Iron/carbon (Fe/C) nanocomposite catalysts are prepared for Fischer-Tropsch synthesis reaction. A preparation method includes steps of mixing iron hydrate salts and a mesoporous carbon support to form a mixture, infiltrating the iron hydrate salts into the carbon support through melt infiltration of the mixture near a melting point of the iron hydrate salts, forming iron-carbide particles infiltrated into the carbon support through calcination of the iron hydrate salts infiltrated into the carbon support under a first atmosphere, and vacuum-drying the iron-carbide particles after passivation using ethanol. Using such catalysts, liquid hydrocarbons are produced.




isc

Stacked catalyst bed for Fischer-Tropsch

The present invention pertains to a reactor tube comprising a fixed bed of Fischer-Tropsch catalyst particles, wherein the catalyst particles in 5% to 40% of the fixed bed volume at the upstream end have an average outer surface to volume ratio (S/V) in the range of between 3.0 to 4.5 mm−1, and the catalyst particles in the remaining fixed bed volume have an average outer surface to volume ratio (S/V) in the range of between 4.5 to 8.0 mm−1, and wherein the difference between the average S/V of the particles at the upstream end and the average S/V of the particles in the remaining fixed bed volume is at least 0.5 mm−1.




isc

Method for producing hydrocarbon oil, fischer-tropsch synthesis reaction device, and hydrocarbon oil production system

The present invention provides a process for producing a hydrocarbon oil by performing a Fischer-Tropsch synthesis reaction using a reactor for a Fischer-Tropsch synthesis including a reaction apparatus having a slurry containing catalyst particles and a gaseous phase located above the slurry to obtain a hydrocarbon oil, wherein the Fischer-Tropsch reaction is performed while controlling a temperature of the slurry so that a difference T2−T1 between the average temperature T1 of the slurry and a temperature T2 at the liquid level of the slurry in contact with the gaseous phase is 5 to 30° C.




isc

Stacked catalyst bed for Fischer-Tropsch

The invention pertains to a reactor tube comprising a fixed bed of Fischer-Tropsch catalyst particles, wherein the catalyst particles in 5%-40% of the fixed bed volume at the upstream end have an average outer surface to volume ratio (S/V) of between 3.0 to 4.5 mm-1, and the remaining catalyst particles have an average S/V of between 4.5 to 8.0 mm-1, and wherein the difference between the average S/V of the particles at the upstream end and the remaining fixed bed volume is at least 0.5 mm-1. Additionally the fixed bed volume at the upstream end shows a full-bed apparent catalytic activity per volume unit lower than the full-bed apparent catalytic activity per volume unit in the remaining fixed bed volume and/or the weight of catalytically active metal per weight unit at the upstream end is more than 70% lower than in the remaining fixed bed volume.




isc

Fischer tropsch method for offshore production risers or oil and gas wells

A method and an apparatus is disclosed that uses a gas lift tubing arrangement to produce synthetic hydrocarbon related products. Using the Fischer Tropsch process as an example, the tubing is packed with a suitable catalyst and then hydrogen and carbon monoxide are injected into the top of the tubing in a fashion similar to a gas lift process. As the gases travel past the catalyst, synthetic hydrocarbons are formed and heat is rejected. The synthetic hydrocarbons and water flow out of the bottom of the tubing and travel up the annulus to the surface. In some embodiments, this process is carried out in a producing well or a in producing riser. In a producing well or a producing riser, the production from the well which flows up the annulus cools the synthetic hydrocarbon derived products. In additional and alternate embodiments, this process can be used in non-flowing wells.




isc

Fischer tropsch method for offshore production risers for oil and gas wells

A method and an apparatus is disclosed that uses a gas lift tubing arrangement to produce synthetic hydrocarbon related products. Using the Fischer Tropsch process as an example, the tubing is packed with a suitable catalyst and then hydrogen and carbon monoxide are injected into the top of the tubing in a fashion similar to a gas lift process. As the gases travel past the catalyst, synthetic hydrocarbons are formed and heat is rejected. The synthetic hydrocarbons and water flow out of the bottom of the tubing and travel up the annulus to the surface. In some embodiments, this process is carried out in a producing well or a in producing riser. In a producing well or a producing riser, the production from the well which flows up the annulus cools the synthetic hydrocarbon derived products. In additional and alternate embodiments, this process can be used in non-flowing wells.




isc

Fischer-Tropsch process

The disclosed invention relates to a process for conducting a Fischer-Tropsch reaction, comprising flowing a reactant mixture comprising fresh synthesis gas and tail gas in a microchannel reactor in contact with a catalyst to form at least one hydrocarbon product, the catalyst being derived from a catalyst precursor comprising cobalt and a surface modified catalyst support.




isc

Hybrid fischer-tropsch catalysts and processes for use thereof

Disclosed are hybrid Fischer-Tropsch catalysts containing cobalt deposited on hybrid supports. The hybrid supports contain an acidic zeolite component and a silica-containing material. It has been found that the use of the hybrid Fischer-Tropsch catalysts in synthesis gas conversion reactions results in high C5+ productivity, high CO conversion rates and low olefin formation.




isc

Fischer-Tropsch synthesis using microchannel technology and novel catalyst and microchannel reactor

Disclosed is a process for converting a reactant composition comprising H2 and CO to a product comprising at least one aliphatic hydrocarbon having at least about 5 carbon atoms, the process comprising: flowing the reactant composition through a microchannel reactor in contact with a Fischer-Tropsch catalyst to convert the reactant composition to the product, the microchannel reactor comprising a plurality of process microchannels containing the catalyst; transferring heat from the process microchannels to a heat exchanger; and removing the product from the microchannel reactor; the process producing at least about 0.5 gram of aliphatic hydrocarbon having at least about 5 carbon atoms per gram of catalyst per hour; the selectivity to methane in the product being less than about 25%. Also disclosed is a supported catalyst comprising Co, and a microchannel reactor comprising at least one process microchannel and at least one adjacent heat exchange zone.




isc

Fischer-tropsch process

The present invention is directed to a process for the production of hydrocarbon product from two different hydrocarbonaceous feedstocks comprising the steps of preparing a feed syngas having a hydrogen/carbon monoxide [H2/CO] molar feed ratio suitable for Fischer-Tropsch synthesis, wherein the feed syngas is prepared by combining a first syngas having a H2/CO molar ratio below the molar feed ratio and a second syngas having a H2/CO molar ratio above the molar feed ratio; the first syngas is prepared from a liquid hydrocarbon comprising feedstock as the sole source of carbon in a first syngas manufacturing process comprising a non-catalytic partial oxidation step; the second syngas is prepared from a methane comprising feedstock as the sole source of carbon in a second syngas manufacturing process comprising a heat exchange reforming step and an auto-thermal reforming step; and the first and second syngas manufacturing processes are operated in parallel.




isc

Method and apparatus for reconditioning digital discs

An automated method for reconditioning a plurality of digital discs within a reconditioning apparatus is disclosed. The method comprises holding the digital discs in a load area, and then transferring each of the digital discs from the load area to at least one workstation with a disc transfer mechanism. The method also comprises reconditioning each of the digital discs transferred to the workstation with at least one worktool operable to remove a portion of the protective coating of each of the digital discs without removal of the data underlying the protective coating. The method further comprises transferring each of the digital discs from the workstation to an unload area with the disc transfer mechanism, and then holding the digital discs in the unload area for manual retrieval. Advantageously, the digital discs may be automatically reconditioned within the reconditioning apparatus without manual manipulation of the digital discs during the reconditioning process. Various exemplary embodiments of the reconditioning apparatus and associated method are provided.




isc

Ethylene based copolymer compositions as viscosity modifiers and methods for making them

Polymeric compositions and methods for making and using the same are provided. The polymeric composition can include a first ethylene-based copolymer and a second ethylene-based copolymer. The first ethylene-based copolymer can have a weight percent of ethylene-derived units based on a weight of the polymeric composition (EA) ranging from about 35 wt % to about 52 wt % and a weight-average molecular weight (MwA) of less than or equal to 130,000. The second ethylene-based copolymer can have a weight percent of ethylene-derived units based on the weight of the polymeric composition (EB) ranging from about 65 wt % to about 85 wt % and a weight-average molecular weight (MwB) of less than 130,000.




isc

Electrode management device for electrical discharge machining machine tools

Device for managing the electrodes for electrical discharge machining EDM machine tools comprises at least one magazine (1) that has a series of individual housings (33) designed to accept and hold exchangeable elements (5) consisting of electrodes (6, 22) mounted on an electrode holder (11a, 11b), and a changer device (2) equipped with a gripper (2) intended to move the exchangeable elements (5) from the individual housings (33) towards the machine and vice versa. A first adapter piece (21) is associated with each of the exchangeable elements (5). This adapter piece (21) surrounds the electrode holder (11a, 11b) and is gripped around its periphery by the gripper (9) of the changer (2) so as to guarantee that the exchangeable element (5) is held precisely. The device further comprises a second adapter piece (32) associated with each of the individual housings (33) of the magazine (1) that are likely to be used.




isc

Method and apparatus for fault discovery in a passive optical network (PON)

An apparatus and method for fault indication and localization in a Passive Optical Network (PON) comprising a multistage power splitter (100, 200, 300) with at least one 1:N splitter (120, 221, 222, 321, 322) followed by N items of 2:M splitters (131, 132, 231-233, 331-336), wherein N and M are integers greater than 1. The apparatus also comprises an Optical Time Domain Reflectometry (OTDR) device (110, 210, 310) capable of inserting an OTDR signal into the power splitter (100, 200, 300), and adapted to insert the OTDR signal between the first stage of the at least one 1:N splitter (120, 221, 222, 321, 322) and the second N items of 2:M splitters (131, 132, 231-233, 331-336).




isc

Optical head device and optical disc device

An optical head device (11) provided with: an optical element (36) for transmissively diffracting a light beam emitted from a semiconductor laser (34), generating a zero-order diffracted light beam and ±1-order diffracted light beams; and a photodetector (40) for receiving the zero-order diffracted light beam and the +1-order diffracted light beam after reflection from an optical disc (2). The photodetector (40) includes a primary light receiving section (400) for receiving the zero-order diffracted light beam, and a first secondary light receiving section (401) disposed outward from the primary light receiving section (400). The first secondary light receiving section (401) is positioned to detect an outer portion of the received light spot of the +1-order diffracted light beam, performs photoelectric conversion of this portion, and outputs a secondary detected signal.




isc

Optical disc with pre-recorded and recordable regions and method of forming the disc

An optical disc having a region with pre-recorded data and a recordable region, a method of fabricating the disc, a stamper for forming a disc master, and a recording device for use with the disc are disclosed. Data recorded in the recordable region may be used for activation of the disc, providing unique identification or enhancing program content on the disc.




isc

Optical disc with pre-recorded and recordable regions and method of forming the disc

An optical disc having a region with pre-recorded data and a recordable region, a method of fabricating the disc, a stamper for forming a disc master, and a recording device for use with the disc are disclosed. Data recorded in the recordable region may be used for activation of the disc, providing unique identification or enhancing program content on the disc.




isc

Method for preparing a gelling and viscosifying agent for drilling mud and the product thereof

A method for preparing lignin graft copolymer comprising: reacting lignocellulosic materials with an acrylic compound by bulk condensation under nitrogen atmosphere in the presence of a non-oxidizing strong organic acid as catalyst; separating the reaction mixture to obtain a solid phase mainly containing lignocellulosic materials and a liquid phase containing lignin graft copolymer and unreacted acrylic compound; and removing solvent from the liquid phase to obtain the lignin graft copolymer.




isc

Intervertebral-disc prosthesis

The intervertebral disc prosthesis comprises first and second plates (3, 4) designed to be attached on one of the two vertebrae adjacent to the intervertebral disc to be replaced, and a compression pad arranged between the first and second plates. Each plate comprises first attaching means including two attaching portions (14a, 14b) positioned symmetrically on either side of the anteroposterior median plane of said plate, second attaching means including two attaching portions (15a, 15b) positioned symmetrically on either side of a first plane inclined by an angle comprised between 50° and 70° relative to the anteroposterior median plane of said plate, and third attaching means opposite the second attaching means relative to the anteroposterior median plane and including two attaching portions (16a, 16b) positioned symmetrically on either side of a second plane inclined by an angle of approximately 90°, relative to the anteroposterior median plane of said plate.




isc

Media content discovery in an integrated media service that distributes media content by way of a plurality of different media distribution models

An exemplary method includes a media service provider system 1) providing an end user of an integrated media service with access to a media program by way of a plurality of different media distribution models, 2) maintaining a catalog that includes comprehensive information about the media program, the comprehensive information being an aggregate of non-redundant information about the media program obtained from a plurality of independent source catalogs corresponding to the plurality of different media distribution models, and 3) providing, based on the comprehensive information included in the catalog, a media service user interface that supports discovery of the comprehensive information about the media program regardless of a user interface context from which a user request for information about the media program is received. Corresponding systems and methods are also described.




isc

Systems and methods for prioritization of data for intelligent discard in a communication network

Systems and methods for optimizing system performance of capacity and spectrum constrained, multiple-access communication systems by selectively discarding packets are provided. The systems and methods provided herein can drive changes in the communication system using control responses. One such control responses includes the optimal discard (also referred to herein as “intelligent discard”) of network packets under capacity constrained conditions. Some embodiments inspect a video stream to determine priorities for various elements of the video stream. The elements may be discarding using the priorities. In various embodiments, the elements include frames, slices, macroblocks, and data partitions.




isc

Methods and systems for adjusting driveline disconnect clutch operation

Systems and methods for improving operation of a hybrid vehicle are presented. In one example, torque transferred via a driveline disconnect clutch is estimated based on characteristics of a torque converter to improve driveline operation.




isc

Battery charge/discharge control device, battery charge/discharge control method, and hybrid working machine with battery charge/discharge control device

A battery charge/discharge control device which performs battery charge/discharge control in a working machine with a battery capable of storing electric energy generated by a generator motor coupled to an engine and driving the generator motor or at least one of other electric actuators by the stored electric energy and a controller which controls a distribution of the electric energy among the battery, the generator motor, and the electric actuator, wherein the controller performs the charge/discharge control in which the electric energy of the battery is discharged when the engine is driven and recharging to the battery is permitted on a condition that a state in which an engine speed is equal to or lower than a predetermined engine speed is maintained for a predetermined time after the battery is completely discharged.




isc

Disc device

A disc device which takes out a disc stored in a magazine and conveys the disc to any disc drive, in which the magazine comprises a tray which stores a plurality of discs, and a case which has a substantially rectangular parallelepiped shape and which stores the tray. The case has an opening at front face into which the tray can be inserted into or taken out therefrom. The tray has an outer shape being substantially rectangular in planar view. The tray is provided with cut portions formed at corner portions positioned on the back side of the case being cut off. The disc device further comprises a picker which holds the tray and draws out the tray from the case. The picker rotates the tray when the cut portion passes through the opening.




isc

Optical disc device and lens cleaner

An optical disc device of the present invention comprises an insertion detection optical sensor which detects insertion of an optical disc based on light emitted from a first light emitting element to a first light receiving element being blocked, and an ejection detection optical sensor provided on the downstream side in the carry-in direction to the insertion detection optical sensor to detect ejection of the optical disc based on light emitted from a second light emitting element to a second light receiving element being blocked. The optical disc device is structured such that, in a state that the optical disc is attached onto the turntable, when the light of the first light emitting element is blocked and the light of the second light emitting element is not blocked, the optical disc device recognizes that a lens cleaner is attached onto the turntable as the optical disc, and the optical disc device performs a cleaning operation.




isc

Optical disc drive

In an optical disc drive, a degradation of traveling performance of an optical pickup under hard acceleration or hard deceleration in a random access operation or the like results in a degradation of recording/reproducing performance. Groove structure is provided between two gears of a guide feed provided in an optical pickup, and the groove forms bending structure. Thus, the engagement state between a screw gear and the gears of the guide feed is stabilized. This makes it possible to prevent tooth jumping and step-out from occurring in the gears during the traveling of the optical pickup, achieving stable traveling. In consequence, the recoding/reproducing performance of the optical disc drive can be improved.




isc

Disc drive unit and apparatus having the same

A disc drive unit is configured with a plurality of disc drives as one unit. At least one of a pair of opposed disc drives arranged on an identical horizontal plane is provided with a tray support member for supporting a front end of a tray of the other disc drive when the tray is ejected. The tray support member is capable of protruding from the one disc drive and withdrawing into the same.




isc

Optical disc device including a carrier for holding optical discs in a stacked state

An optical disc device according to the present invention performs, in parallel, a first control to convey a first tray in the first optical disc drive group from the disc replacing position to the recording and reproducing position, and a second control to convey a second tray in the second optical disc drive group 40R from the recording and reproducing position to the disc replacing position. The second tray is opposed to the first tray.




isc

Media detection during disc insertion

An optical disc drive (ODD) includes one or more sensors which detect a user placing a disc in the loading path. In response, a process is triggered for sensing the thickness of a protective layer of the disc even while the disc is moving toward a turntable. An initial determination of the type of the disc (e.g. CD, DVD or Blu-ray®) can be determined based on the thickness and reported to a host computing device. The host, in turn, determines an application to load based on the disc type. The loading of the application can begin sooner than if the ODD waited until the disc was seated on the turntable to detect the disc type. A final determination of the disc type can be made while the disc is seated as well. The host is informed if there is a disagreement between the initial determination and the final determination.