Showing papers on "Data access published in 1985"

Arbitration system using centralized and decentralized arbitrators to access local memories in a multi-processor controlled machine tool

Abstract: An arbitration system for a machine tool control has multiple processors and a local memory associated with each processor The arbitration system allows one processor to access data stored in a foreign memory, ie the local memory of a second processor so that the time required for one processor to gain access to data used by another processor is relatively short The system includes an external arbitration control which arbitrates requests for access to a foreign memory from each of the processors The system also includes a plurality of local arbitrators each associated with a particular processor to arbitrate requests for access to its processor's bus and memory from a plurality of users including the external arbitration control, a DRAM controller and a direct memory access controller

Semiconductor memory device with improved data write function

Abstract: A semiconductor memory device which has improved and flexible writing function of multi-bit data. The memory has a plurality of data access circuits operable in parallel. Each of the data access circuits includes a data terminal and a data input circuit operatively storing write data applied to the data terminal. A detection circuit is connected to the data terminal, which circuit detects whether a write inhibition signal is applied to the data terminal. In response to the output of the detection circuit, a control circuit selectively disenables the data input circuit.

Beyond two-phase locking

Abstract: Many database systems maintain the consistency of the data by using a locking protocol to restrict access to data items. It has been previously shown that if no information is known about the method of accessing items in the database, then the two-phase protocol is optimal. However, the use of structural information about the database allows development of non-two-phase protocols, called graph protocols, that can potentially increase efficiency. Yannakakis developed a general class of protocols that included many of the graph protocols. Graph protocols either are only usable in certain types of databases or can incur the performance liability of cascading rollback. In this paper, it is demonstrated that if the system has a priori information as to which data items will be locked first by various transactions, a new graph protocol that is outside the previous classes of graph protocols and is applicable to arbitrarily structured databases can be constructed. This new protocol avoids cascading rollback and its accompanying performance degradation, and extends the class of serializable sequences allowed by non-two-phase protocols. This is the first protocol shown to be always as effective as the two-phase protocol, and it can be more effective for certain types of database systems.

Data extraction tools

Abstract: Data analysis includes the acquisition of data from a wide variety of sources, using different media and ranging in size from a few bytes to hundreds of millions of bytes. In the case of large data sets, the problem reduces to finding an efficient way for an analyst or other user to extract useful subsets from the source data with minimal programming knowledge and effort. Since different sources of data often have entirely different protocols, interfaces and procedures for access, the problem is also to reduce the complexity of data access by hiding this variety from the user. We describe a table-driven program generation system that provides a uniform interface to the analysts for requesting portions of data from any source. The system then generates a program that executes on the source system and extracts the requested data. The table-driven nature of the generator can be used to modify the style of the programs being generated. The tables are, in fact, target program abstractions specified in a high-level language. We now have tables that encode efficient C programs to extract data from IBM standard label tapes on UNIX™ systems and COBOL/DL-I/JCL programs to extract data from Information Management System databases.

Delay circuit for a real time clock

Abstract: A delay circuit for a data manipulation circuit is provided in which data update signals to the data manipulation circuit are delayed when a data access signal is present so that data is not manipulated during accessing of the data.

A Module for Improving Data Access and Management in an Integrated CAD Environment

Abstract: A modular system is presented for handling design data, centered around the relational DBMS Ingres, taking advantage of a very careful database schema generation and of the use of software modules to comply with the specific requirements of design data. This work is mainly concerned with one of these modules, called LIPS, which enables the system to handle design data local to an application program with a high level query language, interactive level performances and the ability to support complex design objects. LIPS is composed of two programs: a schema analyzer and a precompiler, and its query language (Loquel) must be embedded in Pascal source code.

Optimizing Data Access in the LAMPF Control System

Abstract: The LAMPF control system data access software offers considerable power and flexibility to application programs through symbolic device naming and an emphasis on hardware independence. This paper discusses optimizations aimed at improving the performance of the data access software while retaining these capabilities. The only aspects of the optimizations visible to the application programs are "vector devices" and "aggregate devices." A vector device accesses a set of hardware related data items through a single device name. Aggregate devices allow run-time optimization of references to groups of unrelated devices. Optimizations not visible on the application level include careful handling of: network message traffic; the sharing of global resources; and storage allocation.

File placement and process assignment due to resource sharing in a distributed system

Abstract: This paper presents a number of solutions to the problems of data access, concurrency control, transaction serialization, and deadlock control based on the examples of existing file systems. Also, policies for file placement and process assignment are discussed from the viewpoint of their impact on system performance and reliability. The impact of these policies depends on the solutions to the problems referred above. A simulation model of a file system is introduced. This model is validated using data collected in a small business installation. A number of simulation experiments are presented. It is shown how the decision about where to place a file or to assign a process can be based on the workload's and the system's characterization. An algorithm for improving performance and reliability by file placement and/or process assignment is finally presented.

From micro to mainframe. A practical approach to perinatal data processing.

Abstract: A new, practical approach to perinatal data processing for a large obstetric population is described. This was done with a microcomputer for data entry and a mainframe computer for data reduction. The Screen Oriented Data Access (SODA) program was used to generate the data entry form and to input data into the Apple II Plus computer. Data were stored on diskettes and transmitted through a modern and telephone line to the IBM 370/168 computer. The Statistical Analysis System (SAS) program was used for statistical analyses and report generations. This approach was found to be most practical, flexible, and economical.

ICHABOD A Data Base Manager for Design Automation Applications

Abstract: ICHABOD, a practical and easily implementable data base manager for Design Automation applications, is described. It is based on key aspects from both the network and relational data models. The user primitives and utilities support open-ended dynamic data structure definition and provide efficient data access mechanisms. Implementation techniques for the physical file structure and memory management are presented. ICHABOD has been successfully incorporated into two Honeywell production Design Automation systems.

Data processing system

Abstract: PURPOSE:To improve the performance of a data processing system by giving an access to data through an idle file controller at a time point when a data access request is given from a data processor CONSTITUTION:When a data access is given to a file device 204, a data processor 200 stores a data access control program to an area for the device 204 within a main memory 201 At this time point the idle one of file controllers 202 and 203 performs a data access In case the controller 202 is idle, the programs for data access control are successively read out with reference to the area where the number of the file controller of the area for the controller 202 is stored Based on these programs, a data access is given to the device 204 The data accesses to other files are also carried out by having a data access through an idle file controller Thus the performance is improved for a data processing system

Exclusive control system of shared data set

Abstract: PURPOSE:To reduce an unnecessary access delay by using a means which reduces the range of exclusive subject data down to a more effective range. CONSTITUTION:A transaction analyzing part 4b of an AIM4 of an on-line data base processing system analyzes a data access request for each transaction of accepted work program and registers corresponding control interval (CI) numbers to a CI control table 7 in the order of access. An exclusive control part 4a' refers to the table 7 and at the same time acquires the information (start/end information, etc.) under control area (CA) division processing from a CA division processing part 5b of a VSAM to execute the exclusive control.

Data base processing system

Abstract: PURPOSE:To avoid useless data access by utilizing field value frequency information with respect to a field designated by the retrieval condition for the access to a residue has edition table data. CONSTITUTION:When the 1st field is designated and the 2nd, 3rd field values are obtained, a field value frequency managing means 92 searches a table to obtain a frequency (c) of a value v1 of a field f1. When the (c) is zero, the data satisfying the retrieval request is not existed. When the (c) is not 0, it is stored and by a residue hash address generating means 93, a start address SA to be accessed and an interval beta of the address are calculated based on the v1. Then a data processing means 94 uses the c, SA and beta to access a hash address table, the access to a real data is conducted bases on the processing to obtain the values of fields f2, f3 matching with the retrieval condition.

Memory control device

Abstract: The invention relates to a memory control device for an information processing system which has a basic processing unit BPU (1), for processing information, a main memory (5), which the BPU (1) accesses, and a buffer memory (4) with reduced data access time. If data which the BPU (1) requests are stored in the buffer memory (5) and can be read out within a predetermined access time, a waiting control signal (17) of ''0'' is set and in other cases of ''1'' is set for a period of time required for the access. An internal system clock in the BPU (1) is prolonged in dependence on the ''1'' waiting-control signal. In addition, a memory-occupied signal of ''1'' is set if the buffer memory (5) or the main memory (4) are in operation. The internal system clock of the BPU is also prolonged in dependence on the memory-occupied signal (13).

Using dimensions to represent attributes

Abstract: In the design of a data base (DB) the grouping of attributes that define or describe a data entity can be represented as an object with many dimensions. This concept can serve as a framework for APL functions which provide efficient data extraction, manipulation and updating. The use of generalized data access functions to respond to specialized data requests can greatly simplify data gathering and reporting system code.

Report of the Joint Industry - DoD Task Force on Computer Aided Logistic Support (CALS). Volume 2. Report of Policy and Legal Constraints Subgroup.

Abstract: : Interface standards are required to describe relational data base criteria for CAD, CAM and CALS. These standards would specify requirements for interchangeability, transportability and access management of digitized data. Interface standards should describe how discrete systems work with each other, rather than how to design and develop each element of the system. A Standard Strategic Program Plan is required to identify standardization opportunities and provide roadmaps for standards development. Standards are also needed to define common terms and data elements for each ILS discipline. A DoD policy should require the establishment of a CALS standard that would act as an index and dictionary for data required for development, acquisition, and post-production. A Joint industry/government team should be tasked to prepare the CALS standards. Data access and file transfer is a policy issue to be resolved by DoD. The government needs to define the CALS logistics data requirements and integrate these with their existing automation systems. Policy for data transfer should assure that contractor files would not have to be recreated by the government. Access or acquisition of data bases is an open issue.

Private voice and data considerations for the AUTOPLEX cellular systems

Abstract: The frequency spectrum in the 850 MHz range which has been made available by the FCC in 1981 to support cellular telecommunications has given carriers the opportunity to provide new communication services to the mobile public. Concurrent with this opportunity is a growing awareness of the need to protect cellular services against eavesdropping. Business and professional cellular system users will require confidential communication with offices and clients, and will therefore need the assurance of privacy in these transactions in order for the service to satisfy their needs. Similarly, the operations of industry, government, and the general public are expanding needs for access to data resources via the cellular radio network. Solving the problem of providing private voice and data services over the cellular radio channel in a way that satisfies the Compatibility Standards associated with the FCC's 1981 Final Report and Order has led to an array of issues relating to the design of the service architecture and to the selection of performance requirements for the signal processing algorithms. This paper addresses these issues.

Data fetch control mechanism

Abstract: PURPOSE:To carry out processing with the smallest number of steps for a data fetch control mechanism by deciding a microprogram containing entries for each data access type and the data access type according to the address and the length of a given operand and branching them to entries of corresponding types of said microprogram. CONSTITUTION:An external data memory 2 stores the data to which access is possible with the word width containing plural byte widths. An external microinstruction memory 3 contains a proper entry for each data access type and stores a microprogram containing a microinstruction which controls the data fetching. A microprocessor 1 contains a sorting means and a processing means, and the sorting means sorts the data access types to the byte string data. While the processing means decides the data access type by the microprogram as well as the address and the length of the byte string data and branches the access type to a proper entry of the microprogram.