Procesamiento en paralelo y distribuido en dos SGBDS: un caso de estudio

Contexto: Una de las estrategias para la gestión de grandes volúmenes de datos es la computación distribuida y en paralelo. Entre las herramientas que permiten aplicar estas características se encuentran algunos sistemas de gestión de bases de datos (SGBD), como Oracle, SQL Sever y DB2.Método: En este artículo se presenta un caso de estudio donde se evalúa el rendimiento de una consulta SQL en dos de estos SGBD. La evaluación se hace mediante diversas formas de distribución de los datos en una red computadores y con diferentes grados de paralelismo.Resultados: Aunque son necesarias pruebas más exhaustivas y con mayor variedad de consultas, se evidenciaron las diferencias de rendimiento entre los dos SGBD analizados.Conclusiones: Las diferencias en rendimiento de los dos SGBDs analizados muestran que a la hora de evaluar este aspecto, se deben considerar las particularidades de cada SGBD y el grado de paralelismo de las consultas.

Research and Development of Online Course Systems

Based on the knowledge management theory, social constructivist theory, the theory ofteam learning, object-oriented programming methods, from the student's learning characteristicsand the technology platform and operating environment and etc., feasibility analysis and needsanalysis are carried out. System design and development are becoming into the design goals ofsocial, intelligence and humanity , the abstract factory design pattern to SQL Sever as a databaseservice system are chosen to be used a number of key technologies, combined with intelligent,high-performance, full-featured search technology, efficient, general purpose, open-to-useWeb-based course system are designed and developed.

The Design of Remote Fault Diagnosis System in Engine Room

To improve the level of ship monitoring, ease the engineer’s working strength, improve the level of the shipping company regulation, the remote fault diagnosis system of ship’s engine room is designed with the comprehensive utilization of neural network, SQL Sever database, C/S structure, the Inmarsat system, etc. The system includes the data acquisition, data storage, the display and control of interface and wireless transmission. The results of application show that the system is stable, easy to use, modification with low cost, helpful for engineer knowing the state of engine room, convenient for unified supervision of the shipping company, improves the work efficiency, safeguards the shipping service.

Design and Implementation of Information Management System for Gas Valve Remote Monitoring and Control

Running in safe and stable status is a core issue of gas valve. An effective method was proposed in this paper to solve the problem of gas valve monitoring and control. The information obtaining and analysis system of gas valve were developed based on visual studio 2005 and sql sever 2005. Multiple functions such as data querying, information management, data statistics and report generation are included in this system. More important, the gas valve working status and key parameters can be monitored and controlled in real-time. While detecting state parameters exceeding the normal range, alarm will be sound and the response people’s cell will be called.

Engine Room Monitoring System Design for Aging Vessels in Coastal Waters

In order to improve the engine room monitoring level of aging ship in coastal waters, to reduce engineers’ work load and to improve the supervision of shipping companies, the present study designs an engine room monitoring system by using VC++ programming technique, SQL Sever database technology, CAN Bus and CDMA 2000 network. The system incorporates such functions as data collection, data storage, interface display and operation, as well as wireless transmission, etc. Application results show that the system is stable, easy to use and incurs a low modifying cost. It facilitates both engineers’ timely control of the engine room status and shipping companies’ uniform supervision of the vessel. Thus the efficiency is improved and ship’s safe navigation is ensured.

Expert System of the Parameter Optimization in the Heavy-Duty Cutting Processing

This paper is focused on using the method of computer technology combined with the knowledge of experts to determine heavy-duty cutting processing parameters according to the relevant theories of metal cutting. This “Expert System of the Parameter Optimization in the Heavy-duty Cutting Processing” is based on the VC++6.0 programming language and SQL Sever 2000. It is divided into two subsystems, turning and milling machining. Taking the turning machining subsystem for example, by using methods of generating expression combined with frame representation, this paper classifies and generalizes related knowledge, and combines the knowledge base with the data base to set up the knowledge base of the subsystem. Also this paper introduces the process of inferential mechanism of the optimizing modules of cutters and machining engagements.