• Journal of KIISE:Computing Practices and Letters
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• v.10 no.1
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• pp.66-74
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• 2004

To get changing data or retrieved information in a web service environment, we need the CGI method in which we designate an executable file and receive the output of the executable file as a document. But the original CGI method has some performance pitfalls caused by the native condition that a process for the requested executable file should be created every time it is requested. Several approaches that make the process as a daemon wholly or partly have been made to solve those problems and they have exclusive strength and weakness. So, many developers are confused when they have to choose which of the CGI methods. We proposed an efficient CGI gateway design called SendFD that the main part of CGI gateway was separated as a daemon and taken over the communication channel by the other small part forked whenever it was requested. Then we testified the efficiency of SendFD styled CGI gateway in real web service environment and it showed about 3% performance improvement compared to the conventional socket pipe method.

• The KIPS Transactions:PartC
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• v.12C no.1 s.97
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• pp.147-156
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• 2005

CGI is a standard interface rule between web server and gateway devised for the gateway's standard output to replace a static web document in UNIX environment. So, it is common to use standard I/O statements provided by the programming language for the CGI gateway. But the standard I/O mechanism is one of buffer strategies that are designed transparently to operating system and optimized for generic cases. This means that it nay be useful to apply another optimization to the standard I/O environment in CGI gateway. In this paper, we introduced standard output method and file output method as the two output optimization areas for CGI gateways written in C language in the UNIX/LINUX systems, and applied the proposed methods of each area to Debian LINUX, IBM AIX, SUN Solaris, Digital UNIX respectively. Then we analyzed the effect of them focused on execution time. The results were different from operating system to operating system. Compared to normal situation, the best case of standard output area showed about $10{\%}$ improvement and the worst case showed $60{\%}$ degradation in file output area where some performance improvements were expected.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.5
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• pp.496-504
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• 2000

The Web gateway is key technology for inter-operating WWW and databases. The previous KRISTAL-II information retrieval system, developed by KORDIC(Korea Research & Development Information Center), used a simple CGI structure web gateway. While the simple CGI structure web gateway is easy to implement, it is not suitable for processing a large number of on-line retrival requests. When considering the growth of the Internet and WWW, it is very important to develop a web gateway efficiently supporting a large number of concurrent users. In this paper, we propose a 3-tier client-server structure web gateway for the KRISTAL-II information system. We also evaluate the performance of the proposed web gateway through experiments.

• Electronics and Telecommunications Trends
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• v.11 no.1 s.39
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• pp.1-8
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• 1996

웹 서비스가 인터넷을 주도하면서 Hyper Text Markup Language(HTML) 문서 위주의 정보검색 서비스에서 한 발 더 나아가 SQL 데이터베이스와 웹을 통합하여 이를 비즈니스 분야로 확대 발전시키기 위한 연구가 진행되고 있다. 실제로 많은 웹 서버에서 Common Gateway Interface(CGI) 기능을 데이터베이스 검색에 활용하고 있다. 이와 함께 GCI를 사용자 입장에서 한 단계 발전시킨 WWW interface to DataBase(WDB), Gateway Structure Query Language(GSQL) 등이 인터넷에서 소개되고 있다. 본 고에서는 현재 다각도로 진행중인 웹과 데이터베이스 통합기술 동향을 CGI와 WDB를 통해 살펴보았다.

• Journal of KIISE:Computing Practices and Letters
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• v.5 no.6
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• pp.663-673
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• 1999

WWW에 있어서 데이타베이스 통로는 필수적이다. 데이타베이스를 이용한 대부분의 웹 서비스는 CGI를 통해서 이루어지고 있는데 본 논문에서는 CGI가 갖는 문제점을 근본적으로 해결하기 위한 프레임웍으로서 JAQS(JAva Query Stub)를 제안하고 있다. JAQS를 통하여 이루어지는 서비스는 HTTP의 비연결성(connectionless) 및 무상태성(stateless)을 극복함으로써 상태 및 트랜잭션 관리를 지원할 수 있음은 물론 자바언어로 구현되어 플랫폼 독립적인 구조와 다중쓰레드를 최대한 활용하고 있다. 또한 JAQS와 함께 제안하고 있는 JAQS 관리자를 이용하면 데이타베이스가 분산되어 있는 환경에서도 효율적으로 동작할 수 있는 구조로 이루어져있다.Abstract Database gateway is absolutely vital to web-based services. Most web-based services with DBMS are implemented using CGI(Common Gateway Interface). This paper proposes a framework, dubbed JAQS(JAva Query Stub), as a solution for problems of CGI. JAQS not only supports state/transaction management by overcoming the connectionless and stateless nature of HTTP, but also effectively guarantees platform/DBMS-independence and multi-threading abilities because JAQS is implemented using Java. Also, using the JAQS Manager additionally proposed in this paper, JAQS can operate efficiently even in distributed database environments.

• The Transactions of the Korea Information Processing Society
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• v.6 no.8
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• pp.1989-1999
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• 1999

Many people are the latest interested in the integration of the WWW and database systems. The UCM(United CGI Management) system, which is proposed on this study, is based on the method using CGI that does not change existing servers and clients to integrate the WWW and database system. Since the CGI executable architecture executes a CGI program whenever the database is accessed, the system performance is reduced greatly when many request to the database are made simultaneously. However, the UCM system improves the system performance since it uses the integrated CGI running a daemon process. Moreover, the proposed system can use the WWW database more economically and doesn't use the SQL because it does not use a DBMS. In UCM system, we define the extended HTML tags to implement the WWW database interface and use the EXODUS storage manager for accessing the database.

• Journal of Power System Engineering
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• v.14 no.1
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• pp.40-46
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• 2010

This paper shows the development process for measuring three-dimensional flow velocity components in a web-browser. The system is developed in an embeddable C/C++ interpreter Ch and Ch-CGI toolkit. The interface for the web-based measurement system consists of a set of web HTML files and Ch files for CGI. All of data in web browser are passed to Ch-CGI script to generate the output of new HTML file. PC-Server and PC-Client can submit measurement parameters and receive the text/graphical results each other. PC-Client can control the test equipment by using a parameters that received from PC-Server. It also can pass the test results between the web-based measurement system. In summary, the designed measurement system is evaluated, the outputs shown well on the web browser.

• The Journal of the Korea Contents Association
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• v.10 no.8
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• pp.73-83
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• 2010

This paper investigates protocol architecture of a Web-ZigBee gateway for interconnecting TCP/IP-based networks and ZigBee/IEEE802.15.4-based wireless sensor networks. The Web-ZigBee gateway delivers data between the TCP/IP network and the ZigBee network. Since those two networks have different communication protocols, a protocol translation mechanism is needed. Herein, we propose a method to deliver query messages from the Internet to the sensor network and receive data from sensors. The protocol translation is performed in the translation layer that is placed above the two application layers, i.e., the Internet application layer and ZigBee application layer. Among various interfaces, we use CGI programming to take care of translation functions efficiently. The CGI manages query information from a client on the Internet and data from the ZigBee sensor network. Whereas the TCP/IP enabled sensor network overlays two heterogeneous communication protocols, overlaying layers increase the complexity and cost of implementing the sensor network. On the contrary, the sensors in our gateway-based system are not only light (because each communication protocol works independently without overlaying), but also efficient because the translation layer mostly alleviates header overloading.

• Journal of Biosystems Engineering
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• v.26 no.2
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• pp.141-146
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• 2001

Lots of the agricultural information come from human experiences and are in non-numerical forms. Therefore, it is difficult to process to be processed in a conventional data processing way. An internet expert system for agricultural application using the ASP(active server page) was developed to solve this problem and consisted of databases, an inference engine, and an user interface. The databases were composed of rule base, question base and link data. The inference engine was developed with the ASP for connection with web between databases. The used interface was developed with the CGI(common gateway interface), so that question could be answered on a web browser, and the session technique was used to provide proper result to each of multi-users. A prototype internet expert system was developed for diagnosis of diseases and nutritional disorders of paddy rice. The expert system was interactively worked through WWW(world wide web) at remote sites by multi-users, even at the same time. The rule base could be easily updated and modified from a web server computer by a knowledge engineer.

• Journal of The Korean Association of Information Education
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• v.7 no.3
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• pp.309-317
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• 2003

Web-Based Education System changed from one side transmission of information to bi-directional information exchange with user. Accordingly, It had been implemented on 3-tier models with each function separation using database and server side language such as CGI (Common Gateway Interface). But, The CBSD(Component Based Software Development) techniques receives many interests recently, and efforts to apply this are appearing. Thus, In this research implemented component base question solving system. For this, I used EJB(Enterprise Java Beans) that is web server component model, and used Petri-Net for typical specification about message flow between components.