Gemini surfactants of bis-N-alkyl polyether, bis-N-alkenyl polyether, bis-N-cycloalkyl polyether, bis-N-aryl polyether bis-beta or alpha-amino acids or their salts, are produced for use as multifunctional corrosion inhibitors, which protect and prevent corrosion of ferrous metals exposed to acidic, basic and neutral liquids when transporting or storing crude oil and liquid fuels. The surfactants are also used to inhibit corrosion of equipment and pipes used in cooling systems in petroleum and petrochemical equipment. The Gemini surfactants have the structural formula:

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.

The present invention is directed to provide a semiconductor surface treating agent; composition which is capable of stripping an anti-reflection coating layer, a resist layer, and a cured resist layer in the production process of a semiconductor device and the like easily and in a short time, as well as a method for treating a semiconductor surface, comprising that the composition is used. The present invention relates to a semiconductor surface treating agent; composition, comprising [I] a compound generating a fluorine ion in water, [II] a carbon radical generating agent; , [III] water, [IV] an organic solvent, and [V] at least one kind of compound selected from a group consisting of hydroxylamine and a hydroxylamine derivative represented by the general formula [1], as well as a method for treating the semiconductor surface, comprising that the composition is used: (wherein R1 represents a linear, branched or cyclic C1-6 alkyl group, or a linear or branched C1-4 substituted alkyl group having 1 to 3 hydroxyl groups; R2 represents a hydrogen atom, a linear, branched or cyclic C1-6 alkyl group, or a linear or branched C1-4 substituted alkyl group having 1 to 3 hydroxyl groups).

A mixture of surfactants from alkylene oxide adducts with different degrees of alkoxylation is used in a urea solution to be added to an exhaust stream for reduction of nitrous gases.

Fault Current Limiters (FCL) provide protection for upstream and/or downstream devices in electric power grids. Conventional FCL require the use of expensive conductors and liquid or gas cryogen handling. Disclosed embodiments describe FCL systems and devices that use lower cost superconductors, require no liquid cryogen, and are fast cycling. These improved FCL can sustain many sequential faults and require less time to clear faults while avoiding the use of liquid cryogen. Disclosed embodiments describe a FCL with a superconductor and cladding cooled to cryogenic temperatures; these are connected in parallel with a second resistor across two nodes in a circuit. According to disclosed embodiments, the resistance of the superconducting components and its sheath in the fault mode are sufficiently high to minimize energy deposition within the cryogenic system, minimizing recovery time. A scheme for intermediate heat storage also is described which allows a useful compromise between conductor length enabled energy minimization and allowable number of sequential faults to enable an overall system design which is affordable, and yet allows conduction cooled (cryogen free) systems which have fast recovery and allows for multiple sequential faults.

A transmission system is provided with a superconductive cable having three phase conductors and a cryostat, surrounding the phase conductors, and encasing a hollow space, for conducting a cooling agent. For the three phase conductors, a common neutral conductor is provided, being made of electrically normally conducting material, carried out as insulating round conductor and placed outside the cryostat and next to it. The cryostat is made of a circumferentially enclosed, thermally insulated sheath.

An inductive fault current limiter (1), has a normally conducting primary coil assembly (2) with a multiplicity of turns (3), and a superconducting, short-circuited secondary coil assembly (4). The primary coil assembly (2) and the secondary coil assembly (4) are disposed at least substantially coaxially with respect to each other and at least partially interleaved in each other. The secondary coil assembly (4) has a first coil section (4a) disposed radially inside the turns (3) of the primary coil assembly (2) and a second coil section (4b) disposed radially outside the turns (3) of the primary coil assembly (2). The fault current limiter has an increased inductance ratio.

Disclosed is a splicing method of two second-generation ReBCO high temperature superconductor coated conductors (2G ReBCO HTS CCs), in which, with stabilizing layers removed from the two strands of 2G ReBCO HTS CCs through chemical wet etching or plasma dry etching, surfaces of the two high temperature superconducting layers are brought into direct contact with each other and heated in a splicing furnace in a vacuum for micro-melting portions of the surfaces of the high temperature superconducting layers to permit inter-diffusion of ReBCO atoms such that the surfaces of the two superconducting layers can be spliced to each other and oxygenation annealing for recovery of superconductivity which was lost during splicing.

A tape-shaped superconducting film-forming substrate is disclosed, which includes a film-forming face for forming a laminate including a superconducting layer thereon, a rear face that is a face at a side opposite to the film-forming face, a pair of end faces connected to the film-forming face and the rear face, and a pair of side faces connected to the film-forming face, the rear face, and the pair of end faces, in which each of the pair of side faces includes a spreading face that spreads toward an outer side in an in-plane direction of the film-forming face from an edge part of the film-forming face toward the rear face side. A superconducting wire and a superconducting wire manufacturing method are also disclosed.

An electrochemical finishing system for super conducting radio frequency (SCRF) cavities including a low viscosity electrolyte solution that is free of hydrofluoric acid, an electrode in contact with the electrolyte solution, the SCRF cavity being spaced apart from the electrode and in contact with the electrolyte solution and a power source including a first electrical lead electrically coupled to the electrode and a second electrical lead electrically coupled to the cavity, the power source being configured to pass an electric current between the electrode and the workpiece, wherein the electric current includes anodic pulses and cathodic pulses, and wherein the cathodic pulses are interposed between at least some of the anodic pulses. The SCRF cavity may be vertically oriented during the finishing process.

A ceramic substrate includes a substrate body formed of ceramic and having a pair of surfaces each assuming a rectangular shape as viewed in plane, and a metallization layer formed on the surface of the substrate body and adapted to braze a metal frame thereon. A composite material layer is disposed between the surface of the substrate body and the metallization layer and is formed such that a ceramic portion, a metal portion 10m formed of a metal similar to a metal component of the metallization layer or a metal which, together with a metal component of the metallization layer, forms an all proportional solid solution, and a glass portion exist together. The thickness of the composite material layer is thinner than that of the metallization layer. A plating layer is deposited on the surface of the metallization layer.

In a terminal structure of a superconducting cable conductor, a terminal portion of the superconducting cable conductor is connected with a terminal member of a good conductor. The terminal portion includes a superconducting layer disposed on an outer periphery of a central support; and an insulating layer surrounding the superconducting layer. The insulating layer and the superconducting layer are partially removed to expose the central support and the superconducting layer in this order from an end of the superconducting cable conductor. The terminal member includes a metal sleeve which includes a first cylindrical portion whose inner surface is in close contact with an exposed portion of the central support; a second cylindrical portion which is soldered around an exposed portion of the superconducting layer; and a third cylindrical portion into which the insulating layer is inserted.

A cooling system includes a first section of high temperature superconducting (HTS) cable configured to receive a first flow of coolant and to permit the first flow of coolant to flow therethrough. The system may further include a second section of high temperature superconducting (HTS) cable configured to receive a second flow of coolant and to permit the second flow of coolant to flow therethrough. The system may further include a cable joint configured to couple the first section of HTS cable and the second section of HTS cable. The cable joint may be in fluid communication with at least one refrigeration module and may include at least one conduit configured to permit a third flow of coolant between said cable joint and said at least one refrigeration module through a coolant line separate from said first and second sections of HTS cable.

Methods, systems, and computer program products are provided for email administration for rendering email on a digital audio player. Embodiments include retrieving an email message; extracting text from the email message; creating a media file; and storing the extracted text of the email message as metadata associated with the media file. Embodiments may also include storing the media file on a digital audio player and displaying the metadata describing the media file, the metadata containing the extracted text of the email message.

An embodiment of an analysis filterbank for filtering a plurality of time domain input frames, wherein an input frame comprises a number of ordered input samples, comprises a windower configured to generate a plurality of windowed frames, wherein a windowed frame comprises a plurality of windowed samples, wherein the windower is configured to process the plurality of input frames in an overlapping manner using a sample advance value, wherein the sample advance value is less than the number of ordered input samples of an input frame divided by two, and a time/frequency converter configured to provide an output frame comprising a number of output values, wherein an output frame is a spectral representation of a windowed frame.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for speech recognition. One of the methods includes receiving a base language model for speech recognition including a first word sequence having a base probability value; receiving a voice search query associated with a query context; determining that a customized language model is to be used when the query context satisfies one or more criteria associated with the customized language model; obtaining the customized language model, the customized language model including the first word sequence having an adjusted probability value being the base probability value adjusted according to the query context; and converting the voice search query to a text search query based on one or more probabilities, each of the probabilities corresponding to a word sequence in a group of one or more word sequences, the group including the first word sequence having the adjusted probability value.

A file managing software program for managing a list of elements in a specific sequence in a first file of a computer program, including the steps of copying the first file to form a second file having an identical list of elements as the first file. The user is then permitted to rearrange the sequence of the elements of the second file independently of the sequence of the first file. A display of both the first and the second file list elements is provided to the user. Further embodiments allow the user to categorize, prioritize, and order according to users specified rules of how the second file element list is organized and displayed to provide a more convenient and flexible presentation of the file contents.

A user interface help dialog for a computer system is provided in which the computer system has a plurality of system parameters and the user interface includes a plurality of command options that may be enabled or disabled. A cursor for indicating one of the command options is also provided. To generate the help dialog the identity of a disabled command option to which the cursor indicates is first identified. The status of a subset of the system parameters is then evaluated, the system parameters subset being determined in dependence on the identified command option. A help dialog to be displayed to the user is then generated, the content of which is dependent on the status of the evaluated system parameters.

A handheld electronic device includes a reduced QWERTY keyboard and is enabled with a disambiguation routine that is operable to disambiguate text input. In addition to identifying and outputting representations of language objects that are stored in the memory and that correspond with a text input, the device is able to perform a spell check routine during input of a text entry and to learn and automatically correct mistakes typically made by the particular user.

Methods and devices for minimizing and maximizing displayed output associated with applications are provided. More particularly, an application presented as two or more pages in a portrait mode can be minimized to present one of the two or more pages following a minimization operation. The page that continues to be displayed can comprise a primary or preferred page, while the page that is dismissed can comprise a secondary or ancillary page. With respect to a maximization operation received with respect to a page of an application results in the display of an additional page associated with that application. Maximization can include controlling the respective screens on which first and second pages of the maximized application are displayed.

Provided is an efficient technology for synthesizing diamino acids (diamino acid derivatives). Disclosed is a manufacturing method for diamino acid derivatives wherein the fluorenyl groups of the diamino acid derivative starting materials represented by General Formula [II] or [IV] are removed.

The invention relates to a process for the aminohydroxylation of alkenes using N-oxycarbamate reagents, e.g. N-acyloxycarbamate, N-alkyloxycarbonyloxycarbamate and N-aralkoxycarbonyloxycarbamate reagents. The invention particularly relates to an intermolecular aminohydroxylation reaction that can be carried out in the absence of added base. The invention also relates to novel N-oxycarbamate reagents that are stable crystalline materials. The process of the invention is useful in the synthesis of compounds having a vicinal amino alcohol moiety, such as biologically active compounds.

A novel substituted N-acetyl-L-cysteine (NAC) derivative and methods of using this compound for the treatment of diseases and/or conditions, including but not limited to diseases and/or conditions of, or involving, the Central Nervous System (CNS), including schizophrenia adrenoleukodystrophy, mitochondrial diseases (e.g. Leigh syndrome, Alpers' disease, and MELAS), Huntington's disease, trichotillomania, HIV-associated neurocognitive disorder, hypoxic-ischemic encephalopathy, drug craving, and drug addiction.

Substituted phenylcarbamoyl alkylamino arenes; substituted phenylthiocarbamyl alkylamino arenes; substituted phenylcarbamoyl alkylamino heteroarenes; substituted phenylthiocarbamyl alkylamino heteroarenes; N-substituted aryl, N'-substituted aryl urea compounds; N-substituted aryl, N'-substituted heteroaryl urea compounds; N-substituted aryl, N'-substituted aryl thiourea compounds and N-substituted aryl, N'-substituted heteroaryl thiourea compounds are provided and may find use as androgen receptor modulators. The compounds may find particular use in treating prostate cancer, including castration-resistant prostate cancer and/or hormone-sensitive prostate cancer.

There is provided a method for producing an aqueous acrylamide solution by reacting a composition including acrylonitrile with water to produce acrylamide, in which the composition including acrylonitrile includes 3 to 15 mg of propionitrile per 1 kg of the total weight of the composition including acrylonitrile. According to the present invention, a production method with which it is possible to suppress acrylamide polymerization without lowering quality and thereby obtain a stable aqueous acrylamide solution can be provided.

Aromatic N-halosulfonamide organic compounds have been known for over one hundred years. The ability of these compounds to release active halogen ions has been utilized in a range of biocidal and fungicidal applications. This disclosure deals with the use of halo active aromatic sulfonamide organic compounds as odor control and/or biocidal agents in a cleaning solution for use with bovines and other dairy animals.

There is provided a method for producing an aqueous acrylamide solution by reacting a composition including acrylonitrile with water to produce acrylamide, in which the composition including acrylonitrile includes 3 to 15 mg of propionitrile per 1 kg of the total weight of the composition including acrylonitrile. According to the present invention, a production method with which it is possible to suppress acrylamide polymerization without lowering quality and thereby obtain a stable aqueous acrylamide solution can be provided.

There is provided a system and method for dynamically generated client side streaming playlists. There is provided a method comprising receiving a request to stream a video asset for playback, retrieving, from a network, a video asset playlist corresponding to the video asset and an ad campaign playlist, generating a consolidated video playlist including the video asset playlist and the ad campaign playlist, and processing the consolidated video playlist using a media playback framework to stream a plurality of video files from the network for decoding and output to a display. Discontinuity tags within the video asset playlist may be utilized as insertion points for portions of the ad campaign playlist. The consolidated video playlist may be accessed through a local HTTP web server, advantageously allowing the use of commonly installed media playback framework models such as QuickTime X to trigger adaptive bitrate support through HTTP Live Streaming.

Internet streaming from broadcast radio or television stations is described wherein triggers for dynamic content from internal or external systems cause an encoder system to generate command messages, and to optionally synchronize those command messages with any delays associated with the triggering events. Command messages are delivered through a streaming media distribution system to client media players which obtain or present the dynamic content, in association with any desired configuration changes to the appearance of the media player or the method or manner in which the dynamic content is presented.

Systems and methods for dynamic development and deployment of computing applications including a development framework, a visual design subsystem, and a deployment subsystem, where at runtime the deployment subsystem is operable to dynamically deploy a computing application realized by a blueprint by sending a request at runtime for graphs and components instantiated by the blueprint.

A printing device includes a printing device side wireless communication unit configured to execute wireless communication with a mobile terminal, an operation acquisition unit configured to acquire user operation thereof, and a processor. The processor is configured to acquire operation data which is generated as the operation acquisition unit acquires a user operation, acquire establishment data which is generated as the printing device side wireless communication unit establishes a wireless communication with the mobile terminal, and issue a request control to control the printing device side wireless communication unit to transmit request data requesting the mobile terminal to transmit print data necessary for printing, via the wireless communication, when the establishment data is acquired, the request control being issued in accordance with the operation data as acquired.

Systems and methods reconfigure data transmitted on a network, the network using a communication protocol. The systems and methods include a processor that is operable to receive data from a second device on the network; a memory medium; and a data configurator operable to dynamically reconfigure the data from the second device, with the data from the second device being in the form of a network item defined by the second device. The data configurator is operable to pass the reconfigured data to the processor and/or the memory medium in the form of a device item that is native to the device. A data design tool generates a map configuration to define a unique relationship between the network item and the device item. The map configuration includes a network representation portion for data in the network item and a device representation portion for data in the data item.

An application framework including different application programming interfaces (APIs) is described which performs a variety of mobile device functions in response to API calls from applications. For example, in response to relatively simple API calls made by applications the application framework manages the complex tasks associated with invitations and matchmaking. By way of example, the details of complex transactions such as establishing peer-to-peer connections between mobile devices may be transparent to the application developer, thereby simplifying the application design process. The application framework may include an application daemon for communicating with a first set of services and an applications services module for communicating with a separate set of services. The application framework may also include a cache for caching data for each of the services based on different cache management policies driven by each of the services. The cache may be updated by push notification cache updates sent from each of the services.

An example method to monitor media exposure involves receiving, at a first internet domain, a first request from a client computer, the first request indicative of access to the media at the client computer. The example method also involves determining if the client computer is known. If the client computer is not known, a response is sent from the first internet domain to the client computer, the response to instruct the client computer to send a second request to a second internet domain, the second request to be indicative of access to the media at the client computer. If the client computer is known, an impression of the media is logged.

A system and method for data communication connecting on-line networks with on-line and off-line computers. The present system provides for broadcast of up to the minute notification centric information thereby providing an instant call to action for users who are provided with the ability to instantaneously retrieve further detailed information. The notification centric portions of information is wirelessly broadcast to wireless receiving devices which are attached to computing devices. Upon receipt of the information at the personal computer, the user is notified through different multimedia alerts that there is an incoming message. Wirelessly broadcasted URL's, associated with the data, are embedded in data packets and provide an automated wired or wireless connection back to the information source for obtaining detailed data.

A method is described for detecting the time messages in the faulty signal of a time-signal transmitter comprising the steps below. Probabilities are assigned to the received information/bits as they are received and whose sign specifies the value of the bit and whose numerical value indicates the certainty of reception. Except for the bits designating the minute information, the probabilities of successive time messages are totaled with time correctness in a one-dimensional memory field. From the totaled probabilities, a reduced time message is reconstructed that initially contains no information on the minutes. If the reconstructed time message does not change over two successive time intervals, and if preset minimum values for the number of probabilities are exceeded for all bits, then the reduced time message is recognized as being correct. The minutes are determined separately and added to the time message recognized as being correct.

Accessory for a laptop computer with LCD display which is connected to the laptop serial communications port and optically transmits data to a portable information device, such as a wristwatch designed to receive data as sequential pulses of light. The accessory includes a microcomputer with an RC timebase which is calibrated each time it is used by a special internal program, so that the input baud rate to the accessory matches the communications baud rate of the data received from the laptop. The internal program also permits selection of an output baud rate for the optically transmitted data.

An equatorial sundial apparatus with an adjustable base assembly utilizing one or more concave cylindrical focusing mirrors. One of the benefits that is derived from this apparatus is the use of one or more concave cylindrical mirrors to project a focused beam of light onto a calibrated surface from which the time can be read. This sundial has the additional benefit of not suffering from blurring of the time indicator in a shadow or non-focused beam of light typical of other sundials. This sundial's focused light forms a sharply demarcated indicator from which time can be read to the minute. A further benefit of this apparatus is the ability to incorporate multiple concave cylindrical focusing mirrors to reduce the size of the visual field or screen where the time is read and to incorporate various shapes and designs for ornamental purposes without significant compromise of the sundials accuracy for telling time. An additional benefit of this apparatus is the ability to quickly, accurately and easily adjust the apparatus to the proper tilt upon setup according to the latitude where it will be located by means of an adjustable base assembly.

A tunable resonator is provided that has a high Q for each resonate frequency. The tunable resonator is a MEMs tunable resonator wherein the tuner is affected by moving a moveable mass, associated with the resonating portion of the resonator, form a first position to a second position such that the moveable mass is held in the first position or second position by a detent rather than a constant electromagnet magnetic or electrostatic force applied thereon.

A wristwatch, which comprises an atomic oscillator comprising a system for detecting the beat frequencies obtained by the Raman effect.

Smoking cessation lighter is configured for lighting cigarettes for a smoker, and learning software is provided for monitoring smoking behavior of a smoker during a first data collection period and guiding a smoker's smoking cessation by directing the smoker when the smoker is to smoke a cigarette based on data collected during the first data collection period. The learning software monitors user behavior and collects data during use of the lighter by the smoker after the initial data collection period in order to analyze and further guide the smoker based on the smoker's cheating behavior, the smoker's behavior of lighting a cigarette for a friend, and the smoker's behavior of skipping use of the lighter at a time when the smoker has been directed to light a cigarette by the lighter.

A computing system includes a plurality of dispersed storage (DS) processing units operable to receive a continuous data stream, simultaneously disperse storage error encode the continuous data stream to produce a plurality of encoded data slices and store the plurality of encoded data slices in a DS memory.

A memory storage apparatus, a memory controller and method for transmitting and identifying data streams are provided. The memory controller passes at least a portion of a data stream received from a host system to a smart card chip of the memory storage apparatus. Then, the host system accurately receives a response message from the smart card chip by executing a plurality of read commands. The memory controller is capable of adding a first verification code to a response data stream sent to the host system, and is capable of adding a write token to each of data segments of the response data stream. The host system confirms the accuracy of the response data stream by verifying the first verification code or by verifying the write token of each of the data segments.

A method, a system and a computer program product for enhancing a cache back invalidation policy by utilizing least recently used (LRU) bits and presence bits in selecting cache-lines for eviction. A cache back invalidation (CBI) utility evicts cache-lines by using presence bits to avoid replacing a cache-line in a lower level cache that is also present in a higher level cache. Furthermore, the CBI utility selects the cache-line for eviction from an LRU group. The CBI utility ensures that dormant cache-lines in the higher level caches do not retain corresponding presence bits set in the lower level caches by unsetting the presence bits in the lower level cache when a line is replaced in the higher level cache. Additionally, when a processor core becomes idle, the CBI utility invalidates the corresponding higher level cache by unsetting the corresponding presence bits in the lower level cache.

In a computer system that includes multiple nodes and multiple logical partitions, a dynamic partition manager computes current memory affinity and potential memory affinity to help determine whether a reallocation of resources between nodes may improve memory affinity for a logical partition or for the computer system. If so, the reallocation of resources is performed so memory affinity for the logical partition or computer system is improved. Memory affinity is computed relative to the physical layout of the resources according to a hardware domain hierarchy that includes a plurality of primary domains and a plurality of secondary domains.

Various systems and methods are described for configuring a logical data storage container. In one embodiment, an instruction to perform an operation to modify an attribute of the logical data storage container that is an abstraction of a plurality of pertinent storage containers is received. A translated instruction to perform a sub-operation associated with the operation is transmitted to each of a number of the plurality of pertinent storage containers. A level of success of the performing of the operation on the logical data storage container is detected based on a comparison of a threshold value to a level of success of the performing of the sub-operation on each of the number of the plurality of pertinent storage containers. A report of the detected level of success is communicated.

A partition manager relocates a logical partition from a primary shared processor pool to a secondary shared processor pool in response to a predetermined condition, such as a hardware failure. The relocated logical partition is allocated a smaller quantity of processing units from the secondary pool than it was allocated from the primary pool. A quantity of processing units reserved for a second logical partition is identified in the secondary shared processor pool, and a portion of those reserved processing units are allocated to the relocated logical partition. The reserved processing units may be redistributed among multiple relocated logical partitions.

The invention pertains to a memory management unit for a microprocessor system, the memory management unit being connected or connectable to at least one processor core of the microprocessor system and being connected or connectable to a physical memory of the microprocessor system. The memory management unit is adapted to selectively operate in a hypervisor mode or in a supervisor mode, the hypervisor mode and the supervisor mode having different privilege levels of access to hardware The memory management unit comprises a first register table indicating physical address information for mapping at least one logical physical address and at least one actual physical address onto each other; a second register table indicating an allowed address range of physical addresses accessible to a process running in or under supervisor mode; wherein the memory management unit is adapted to prevent write access to the second register table by a process not in hypervisor mode. The memory management unit is further adapted to allow write access to the first register table of a process running in or under supervisor mode to reconfigure the physical address information indicated in the first register table with memory mapping information relating to at least one physical address, if the at least one physical address is in the allowed address range, and to prevent write access to the first register table of the process running in or under supervisor mode if the at least one physical address is not in the allowed address range. The invention also pertains to a microprocessor system and a method for managing memory.

A prefetch optimizer tool for an information handling system (IHS) may improve effective memory access time by controlling both hardware prefetch operations and software prefetch operations. The prefetch optimizer tool selectively disables prefetch instructions in an instruction sequence of interest within an application. The tool measures execution times of the instruction sequence of interest when different prefetch instructions are disabled. The tool may hold hardware prefetch depth constant while cycling through disabling different prefetch instructions and taking corresponding execution time measurements. Alternatively, for each disabled prefetch instruction in the instruction sequence of interest, the tool may cycle through different hardware prefetch depths and take corresponding execution time measurements at each hardware prefetch depth. The tool selects a combination of hardware prefetch depth and prefetch instruction disablement that may improve the execution time in comparison with a baseline execution time.

A dynamically expandable and contractible fault-tolerant storage system employs a virtual hot spare that is created from unused storage capacity across a plurality of storage devices. This unused storage capacity is available if and when a storage device fails for storage of data recovered from the remaining storage device(s). On an ongoing basis, the storage system may determine the amount of unused storage capacity that would be required for the virtual hot spare (e.g., based on the number of storage devices, the capacities of the various storage devices, the amount of data stored, and the manner in which the data is stored) and generate a signal if additional storage capacity is needed for a virtual hot spare.