Abstract: Keyword proximity searching in a document database according to a query condition initiates with generation of inverted lists having a location for each instance of the keyword in the document database. A plane-sweep mode is used to efficiently search the inverted lists until an output tuple satisfying proximity criteria in the search query is detected. The method then shifts to a nested-loop search mode to enumerate all possible combinations of the keyword instances that satisfy the proximity search query which are in the neighborhood of the output tuple detected in plane-sweep mode. The method alternates between these two modes of operation until all of the output tuples satisfying the query condition are enumerated.

Abstract: A method for searching for a query word in a database of automatically recognized text generated, for example by an optical character recognition (OCR) system or a speech recognition (SR) system finds entries that most closely match the query word. The database is indexed into a trie data structure, which represents all possible words in the database. The trie data structure has a plurality of branch nodes, each representing a letter of at least one word, and a plurality of leaf nodes, each representing a respective word. The trie data structure is searched for each query word by selecting the first letter of the query word and also selecting a root node in the trie data structure as the current node. All possible child nodes of the current node are identified. Respective estimated probability values for matching respective letters of the query word with the letters associated with the nodes in the path taken through the trie data structure are calculated for each identified child node.

Abstract: A distributed file system using autonomous disks is disclosed. The file system includes autonomous data disks that store the application data of the distributed file system. Legacy attribute disks store the file system's meta-data and directory structure. The directory structure is stored on the legacy attribute disks using the native file system. One of the clients of the file systems is utilized as a configuration manager to control access to the system. The distributed file system employs agents to support real-time applications and concurrent read/write to files.

Abstract: A computer-implemented scheduling method and apparatus for scheduling operations relating to a predetermined activity. The activity includes scheduling operations of network-attached storage devices, or other computer-related operations, or non-computer related operations, such as manufacturing plant operations. Operational data is received that is indicative of the operations. Attributes regarding the received operational data are identified. A linear ordering of the attributes is imposed via a predetermined curve. The curve is an aggregation of at least substantially continuous functions from intervals so as to form a substantially repetitive pattern. Operations are scheduled based upon the imposed linear ordering. With such an approach, the overall performance aspects of the system is significantly improved.

Abstract: A method is provided for keyword proximity searching in a document database. An inverted list is constructed for each keyword in a query condition, where each list includes a location for each instance of the keyword in the document database. A plane-sweep mode is used to efficiently search the inverted lists, thereby excluding tuples that do not contribute to the output. Once an output tuple satisfying the proximity search query is detected, the plane-sweep mode is terminated. Because of the nature of the proximity search query, some tuples that are in the proximity of the output tuple also satisfy the proximity condition. Hence, the method also employs a nested-loop mode. The nested-loop mode performs a local nested loop join to enumerate all possible combinations of the keyword instances that satisfy the proximity search query which are in the neighborhood of the output tuple detected by plane-sweep mode. Upon enumerating all of these output tuples, the method switches back to the plane-sweep mode.

Abstract: A process is presented for supporting simultaneous disk read and write requests in a video server environment. Read requests are the result of movie viewing, while write requests are the result of video clip editing or movie authoring procedures. Due to real-time demands of movie viewing, read requests have to be fulfilled within certain deadlines, otherwise they are considered lost. Since the data to be written into disk is stored in main memory buffers, write requests can be postponed until critical read requests are processed. However, write requests still have to be proceeded within reasonable delays and without the possibility of indefinite postponement. This is due to the physical constraint of the limited size of the main memory write buffers. The new process schedules both read and write requests appropriately, to minimize the amount of disk reads that do not meet their presentation deadlines, and to avoid indefinite postponement and large buffer sizes in the case of disk writes.

Abstract: Multi-media servers provide clients with streaming data requiring soft real-time guarantee and static data requiring a large amount of storage space. The servers use a pull-mode protocol to communicate with clients through a real-time network. Separate data and control channels enhance the soft real-time capability of the server. The data channel conforms to open standard protocol. A switched data link layer for the control channel permits separate intrahost control messages that may be multicast and broadcast. The distributed file system selects a specific data block size based upon the compression technique employed to enhance soft real-time guarantee. A hierarchal data structure combined with merging empty data blocks minimizes disk fragmentation. Data blocks are striped across multiple disks to improve disk utilization. A local buffer and a queue for both read and write requests provides support for simultaneous read and write data streams.

Abstract: A transport system allows delivery of MPEG video streams from a network server to a media client while avoiding network delays associated with transition between files contained in these streams. A buffering system, a transport controller, and a counter allow buffering and interim delivery of MPEG stream data. The transport controller can either deliver MPEG stream data directly to the media client, or route data through the buffering system. The buffering system includes a population buffer for storage of interim MPEG stream data, and a transport buffer for temporary storage of MPEG stream data during continuous delivery. During transitional delivery, the transport controller delivers interim data to the media client until the requested file is available and uses the counter to select the proper start location in the requested file.

Abstract: The distributed multimedia server employs modular server elements that connect with client systems through a high bandwidth network. The server elements are connected in interleaved fashion with the switching elements and the data representing different media selections are arranged in stripe groups distributed across the server elements. The server can be as small as a single server element or grown incrementally, as needed, by connecting additional server elements to the system. Multiple copies of hot media selections are stored across the distributed architecture within different stripe groups to minimize bottlenecks within the storage subsystem.

Abstract: The disk scheduling system supports the processing of simultaneous storage device read and write requests in a video server environment, thereby supporting both video-on-demand and non-linear editing applications. Read requests are the result of movie viewing, while write requests are the result of video clip editing or movie authoring procedures. Due to real-time demands of movie viewing, read requests have to be fulfilled within certain deadlines, otherwise they are considered lost. Since the data to be written into the storage device is stored in main memory buffers (or write buffers), write requests can be postponed until critical read requests are processed. However, write requests still have to be proceeded within reasonable delays and without the possibility of indefinite postponement. This is due to the physical constraint of the limited size of the main memory buffers.

Abstract: A method is disclosed for matching input data representing a continuous combination of input objects to a plurality of objects in a trie database structure. This data structure has a plurality of nodes partitioned into a plurality of levels. Each node in the Trie includes a plurality of elements where each element corresponds to a respective one of the component objects. In addition, a hidden Markov model corresponding to the component object is associated with the element in the database. According to the method, the input object is applied to each of the hidden Markov models associated with the respective plurality of elements of a node to generate a respective plurality of acceptance values. The element which generates the largest acceptance value is identified with a segment of the input data. The component object for this element is recorded and the identified segment is deleted from the input data string.