Abstract: A file level striping method adds an option for indicating whether or not to support file level striping to a file creation interface in a file system, extends an inode structure to include a last disk ID field, initializes the last disk ID when the file is created in the file system, allocates a physical block based on the last disk ID when the physical block allocation is requested at the time of file I/O request in the file system, and modifies the last disk ID value to reflect the physical block allocation made by a volume manager. An apparatus using the file level striping method includes a number of disks for storing information actually, the volume manager for logically grouping a number of disks and a file system for creating files on said logical volume and performing I/O operations.

Abstract: A cache consistency maintenance procedure to select one of a detection-based cache consistency maintenance procedure optimized for record-based locking and an avoidance-based consistency-based maintenance procedure optimized for table and block-based locking. To support the characteristic of DBMS in which table locking and record locking are consistent to access the same table, the two kinds of the consistency maintenance policies for the same block are processed by a single buffer load process and the two kinds of the consistency maintenance policies are consistent with each other to provide better configuration and performance.

Abstract: An efficient snapshot technique based on a mapping for a large logical volume shared in multiple hosts. According to the present invention, problems of time delays in a conventional snapshot technique is solved by employing a FAB and an SSB, which are bits representing whether a COW operation is carried out to a mapping entry. In other words, the present invention solves the problems of delaying a write operation of corresponding volume, which is simultaneously executed when a snapshot is created, until the snapshot creation is completed.

Abstract: Disclosed a method of designing a watermark having the power spectral density optimized so that the detection performance can be improved by employing the whitening filtered detection after the Wiener attack. The power spectral density of the watermark is designed using an optimization method that can improve the entire detection performance by reflecting the gain of the whitening filter after the Wiener attack. A higher detection gain is obtained using the whitening filter after the Wiener attack, and the expected value of the difference between test statistics of the two hypotheses that the watermark exists and the watermark does not exist, respectively, is maximized to optimize the detection performance. Regarding the expected value of the difference between the test statistics as an objective function, the power spectral density of the watermark, which corresponds to a maximum differentiated value of the power spectral density of the watermark using the Lagrange multiplier method, is obtained.

Abstract: An object-based storage device with a low process load and a control method thereof are provided. The object-based storage device includes: a storage unit; a temporary storage unit; a transmission unit; a first control unit; and a second control unit. Particularly, the temporary storage unit and the transmission unit are provided separate from the main storage unit and the system bus, and these separately provided temporary storage unit and transmission unit allow a direct data transmission, which attributes to a reduction in a process load and a burden on the system bus.

Abstract: Provided are a hardware device and a method for creating and managing socket information serving as a connection with a network protocol hierarchy in a network application program. The hardware device includes a TCP transmission processor for processing commands on requests for creating and eliminating a socket of a predetermined network program in response to the requests for creating and eliminating a socket, a TCP reception processor for creating a search signal for a corresponding socket identification when a new packet is received, a socket management unit for creating and eliminating a socket ID upon a command from the TCP transmission processor, and searching the socket ID and providing the socket ID to the TCP transmission processor upon a command from the TCP reception processor, and a memory unit for storing the socket information, and providing the socket information to the TCP reception processor.

Abstract: A device for effectively and economically receiving a packet by eliminating temporary memory and a memory controller. The apparatus includes an inspection logic circuit for inspecting data units as soon as they arrive in order to find an error included in the packet and generating control signals according to a result of inspecting a data unit; a multiplexer for receiving data units and distributing the received data units as soon as the data units have arrived; and FIFO memories for receiving the data unit, storing the data unit in a corresponding one of FIFO memories and either deleting or completing storing data units according to the control signals from the inspection logic circuit. The present invention can reduce manufacturing cost of the device by eliminating a temporary memory and a memory controller for the temporary memory and can also reduce processing time.

Abstract: Disclosed is a method for embedding and extracting a spatial domain blind watermark using a sample expansion. The sample expansion method using a sample expansion coefficient is introduced to basically improve a common disadvantage of the conventional watermarking method based on the patchwork method, for instance, the watermark is not robust against a compression attack such as JPEG. By applying the sample expansion to a sample group, the embedded watermark comes to contain a low frequency component more larger than ever, so that radio frequency component decreases as much. Thus, although the radio frequency component of the watermark is damaged by the image compression such as JPEG, it is possible to relatively reduce the damage of the watermark. Also, an adaptive watermark embedding method can be considered such that the embedded watermark value is proportional to an average value of the pixel.

Abstract: A method for file deletion and recovery against system failures in a database management system comprising steps of deleting files listed in a pending action list during a transaction commit process, writing a non-atomic file deletion as an atomic operation into a log and recovering uncompleted file deletion during restart recovery by using the log is disclosed. When system failures occur during file deletion in a database management system, resources of which releasing is interrupted by failures are released perfectly through recovery step, so it is advantageous in that coherency of data is maintained and efficiency of storage device arises.

Abstract: Disclosed is an XML database duplicating apparatus and method capable of providing an effective application service without interruption at a low cost in the diverse Internet environments by copying an XML document of a database system mounting an XML processing technique to another remote server. When the XML document stored in a database of the original server is copied to databases of copied servers, the structure and attribute information included in the XML document are maintained as they are, and thus the respective copied servers can support the searches based on the contents and the attribute provided by an XML query language and disperse users' queries concentrated to the original server to the respective copied servers, so that the service request for application programs can be processed.

Abstract: The present invention is a data transfer protocol control system with a host bus interface that includes a transmitting/receiving command DMA, a transmitting data DMA and a receiving data DMA for controlling data transfer protocol with a host bus interface considering characteristic, usage frequency, simultaneous processing functions of the command DMA and the data DMAs. A host interface bus is efficiently used and bus usage ratio is distributed properly to support transfer flow properly and improve the entire system performance.

Abstract: In a first-in first-out memory circuit using a standard cell library memory, a memory block includes N number of memories (N>1). A read pointer designates read addresses of the N number of memories. A write pointer designates write addresses of the N number of memories. A memory controller selects one from the N number of memories based on the read/write addresses, generates n number of read/write clock signals by demultiplying a clock signal by n (n=N, n>1) and sends the n number of read/write clock signals having a 1/n cycle difference to the N number of memories thereby inputting/outputting data.

Abstract: The present invention relates to a cache coherency maintaining method for a database management system (DBMS) operating in a multi-system sharing a disk, and more particularly, to buffer installation method supporting detection-based and avoidance-based consistency maintenance policy in a shared disk-based multi-DBMS improved to select the procedure for each type and allow all procedures to be consistent using the characteristic of the DBMS controlled coherently by unit of table, block and record. To achieve this, the present invention provides a cache consistency maintenance procedure to select one of detection-based cache consistency maintenance procedure optimized for record-based locking and avoidance-based consistency-based maintenance procedure optimized for table and block-based locking.

Abstract: The present invention is a data transfer protocol control system with a host bus interface that includes a transmitting/receiving command DMA, a transmitting data DMA and a receiving data DMA for controlling data transfer protocol with a host bus interface considering characteristic, usage frequency, simultaneous processing functions of the command DMA and the data DMAs. A host interface bus is efficiently used and bus usage ratio is distributed properly to support transfer flow properly and improve the entire system performance.

Abstract: A file level striping method adds an option for indicating whether or not to support file level striping to a file creation interface in a file system, extends an inode structure to include a last disk ID field, initializes the last disk ID when the file is created in the file system, allocates a physical block based on the last disk ID when the physical block allocation is requested at the time of file I/O request in the file system, and modifies the last disk ID value to reflect the physical block allocation made by a volume manager. An apparatus using the file level striping method includes a number of disks for storing information actually, the volume manager for logically grouping a number of disks and a file system for creating files on said logical volume and performing I/O operations.

Abstract: An apparatus for effectively and economically receiving packet by eliminating temporal memory and controller is disclosed. The apparatus includes; an inspection logic circuit for inspecting data units as soon as arrived in order to find error included in the packet and generating control signals according to a result of inspecting data unit; a multiplexer for receiving data units and distributing the received data units as soon as the data units are arrived; and a plurality of FIFO memories for receiving the data unit, storing the data unit in corresponding one of FIFO memories and deleting or completing to store data units according to the control signals from the inspection logic circuit. The present invention can reduce manufacturing cost of the apparatus by eliminating a temporal memory and a memory controller for the temporal memory and can also reduce a processing time.

Abstract: In a first-in first-out memory circuit using a standard cell library memory, a memory block includes N number of memories (N>1). A read pointer designates read addresses of the N number of memories. A write pointer designates write addresses of the N number of memories. A memory controller selects one from the N number of memories based on the read/write addresses, generates n number of read/write clock signals by demultiplying a clock signal by n (n=N, n>1) and sends the n number of read/write clock signals having a 1/n cycle difference to the N number of memories thereby inputting/outputting data.

Abstract: The present invention relates to an efficient snapshot technique based on a mapping for a large logical volume shared in multiple hosts. According to the present invention, problems of time delays in a conventional snapshot technique is solved by employing a FAB and an SSB, which are bits representing whether a COW operation is carried out to a mapping entry. In other words, the present invention solves the problems of delaying a write operation of corresponding volume, which is simultaneously executed when a snapshot is created, until the snapshot creation is completed. Further, in the write operation carried out after the snapshot creation, an operation of determining whether the COW operation is carried out is achieved by reading only an original mapping block by using the FAB and the SSB, without reading out the snapshot mapping block.

Abstract: Disclosed a method of designing a watermark having the power spectral density optimized so that the detection performance can be improved by employing the whitening filtered detection after the Wiener attack. The power spectral density of the watermark is designed using an optimization method that can improve the entire detection performance by reflecting the gain of the whitening filter after the Wiener attack. A higher detection gain is obtained using the whitening filter after the Wiener attack, and the expected value of the difference between test statistics of the two hypotheses that the watermark exists and the watermark does not exist, respectively, is maximized to optimize the detection performance. Regarding the expected value of the difference between the test statistics as an objective function, the power spectral density of the watermark, which corresponds to a maximum differentiated value of the power spectral density of the watermark using the Lagrange multiplier method, is obtained.

Abstract: A recovery method for a high-dimensional index structure is disclosed, in which a reinsert operation is employed based on ARIES (algorithm for recovery and isolation exploiting semantics) and a page-oriented redo and a logical undo. Further, a recording medium on which a program for carrying out the above method is recorded is disclosed, the program being readable by a computer. The recovery method for a high-dimensional index structure employing a reinsert operation according to the present invention includes the following steps. At a first step, an entry is inserted into a node, a minimum bounding region is adjusted, an overflow is processed, and a log record is stored. At a second step, the log record thus stored is recovered.