• Proceedings of the IEEK Conference
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• 2003.11b
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• pp.73-76
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• 2003

Current web-server deals a multimedia data as well as text data. But dealing a multimedia data is high burden to web-server. So it can degrade web-server response. We introduce H/W feature CDA (Contents Delivery Accelerator). Main function of this H/W is transferring data between SCSI disk and NIC by direct path, and TCP offloading. These 2 functions can accelerate web-server performance. In this paper we will explain problem of current web-server and suggest our new architecture and say various implementation issues.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.4
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• pp.157-170
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• 1999

The web-based groupware systems hold many possibilities for system developers and users. Especially, web-based group collaborative systems are emerging as enterprise-wide information systems. Since data in group collaborative systems are apt to be shared among multiple concurrent users and modified simutaneously by them, the web-based group collaborative systems must support synchronous collaboration in order to provide users with synchronized and consistent views of shared data. However, current web technologies have limitations in supporting this, largely because the existing Hypertext Transfer Protocol(HTTP) is unidirectional and does not allow web servers to send messages to their web browsers without first receiving requests from them. This paper proposes an active web server that can overcome such limitations and facilitate synchronous collaboration in web-based group collaborative systems. To accomplish such goals, the active web server manages dependency relationships beween shared data and web browsers referencing them and actively propagates changing details of the shared data to all web browsers referencing them. And, this paper examines usefulness and effectiveness of the active web server to apply it to the ball-bearing design example of concurrent engineering design systems. The prototype system of the active web server is developed on a commercial Object-oriented Database Management System(0DBMS) called OBJECTSTERE using the C++ programming language.

• The Journal of the Korea Contents Association
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• v.13 no.6
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• pp.30-39
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• 2013

Web crawler should maintain fresh data with minimum server overhead for large amount of data in the web sites. The overhead in the server increases rapidly as the amount of data is exploding as in the big data era. The amount of web information is increasing rapidly with advanced wireless networks and emergence of diverse smart devices. Furthermore, the information is continuously being produced and updated in anywhere and anytime by means of easy web platforms, and smart devices. Now, it is becoming a hot issue how frequently updated web data has to be refreshed in data collection and integration. In this paper, we propose dynamic web-data crawling methods, which include sensitive checking of web site changes, and dynamic retrieving of web pages from target web sites based on historical update patterns. Furthermore, we implemented a Java-based web crawling application and compared efficiency between conventional static approaches and our dynamic one. Our experiment results showed 46.2% overhead benefits with more fresh data compared to the static crawling methods.

• Korean Journal of Computational Design and Engineering
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• v.9 no.3
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• pp.260-265
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• 2004

This paper proposed a Web-based training service for product data management by supporting an integrated product data management system, various technical documents. and efficient communication systems. It also supports a general product development process and a consistent product data model that enable participants to experience management of consistent product information during the product development life cycle. The Web based environment of the service also provides participants with a collaborative workplace with other participants and a Web portal for all the components of the service.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.488-490
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• 2003

Over the past few years, a number of studies have been made on web map services, which enable the GIS user to access spatial data through the web. They, however, have focused on only implementation techniques separately, such as map client implementation, map server implementation, communication between client and server, and the map data representation. Therefore, it is hard to share and practical use the spatial data, because they does not ensure interoperability in heterogeneous map servers. In this paper, we have designed and implemented the web map server with open architecture, which complies with the standard interfaces proposed by OpenGIS Consortium (OGC). In particular, we have extended the OGC’s interfaces for a map server to support one or more data sources. This paper has contributed to construction and practical use of web map services by newly proposing the method of implementation of a map server, which could be reused regardless of the types of data sources.

• Journal of Korea Multimedia Society
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• v.21 no.2
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• pp.199-209
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• 2018

Recently, services provided to consumers are increasingly being combined with big data such as low-priced shopping, customized advertisement, and product recommendation. With the increasing importance of big data, the web crawler that collects data from the web has also become important. However, there are two problems with existing web crawlers. First, if the URL is hidden from the link, it can not be accessed by the URL. The second is the inefficiency of fetching more data than the user wants. Therefore, in this paper, through the Casper.js which can control the DOM in the headless brwoser, DOM event is generated by accessing the URL to the hidden link. We also propose an intelligent web crawler system that allows users to make steps to fine-tune both Structured and unstructured data to bring only the data they want. Finally, we show the superiority of the proposed crawler system through the performance evaluation results of the existing web crawler and the proposed web crawler.

• Journal of Internet Computing and Services
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• v.20 no.3
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• pp.43-59
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• 2019

Today, with the spread of smartphones and the development of social networking services, structured and unstructured big data have stored exponentially. If we analyze them well, we will get useful information to be able to predict data for the future. Large amounts of data need to be collected first in order to analyze big data. The web is repository where these data are most stored. However, because the data size is large, there are also many data that have information that is not needed as much as there are data that have useful information. This has made it important to collect data efficiently, where data with unnecessary information is filtered and only collected data with useful information. Web crawlers cannot download all pages due to some constraints such as network bandwidth, operational time, and data storage. This is why we should avoid visiting many pages that are not relevant to what we want and download only important pages as soon as possible. This paper seeks to help resolve the above issues. First, We introduce basic web-crawling algorithms. For each algorithm, the time-complexity and pros and cons are described, and compared and analyzed. Next, we introduce the state-of-the-art web crawling algorithms that have improved the shortcomings of the basic web crawling algorithms. In addition, recent research trends show that the web crawling algorithms with special purposes such as collecting sentiment words are actively studied. We will one of the introduce Sentiment-aware web crawling techniques that is a proactive web crawling technique as a study of web crawling algorithms with special purpose. The result showed that the larger the data are, the higher the performance is and the more space is saved.

• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.831-840
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• 2001

In this study, We introduce the process of web usage mining, which has lately attracted considerable attention with the fast diffusion of world wide web, and explain the web log data, which Is the main subject of web usage mining. Also, we illustrate some real examples of analysis for web log data and look into practical application of web usage mining for eCRM.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.89-91
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• 2004

In SCADA systems, an RTU is a device installed at a remote location that collects data, codes the data into a format that is transmittable and transmits the data back to a central station, or MTU. An RTU also collects information from the master device and implements processes that are directed by master device. RTUs are equipped with input channels for sensing or metering, output channels for control, indication or alarms and a communications port. In general, the data are transmitted via a wired communication infrastructure such as RS422 or RS485 between RTU and MTU. But, limited range of wired communication doesn't allow the system to cover remote areas over the limitation, and building a wired communication network is not easy in the circumstances. In this Paper, we design and implement a smart cost-effective Web-RTU that can communicate with MTU via Web. Web is of benefit to the Web-RTU, because it is not only free from the distance limitations, but also is built easily and cost-effectively wherever Internet resources are available. Additionally, Web can be easily applied to the SCADA system with the development of hardware and software for communications. The Web-RTU has a program memory, a data memory and a RAM inside, and uses Atmega128, low-cost 8 bit micro-processor with eight AI(Analog Input). It performs well enough to implement all existing roles of RTU.

• Journal of the Korean Data and Information Science Society
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• v.14 no.2
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• pp.217-221
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• 2003

Modeling the reliability of distributed systems requires a good understanding the reliability of the components. For thousands of web users, competitiveness in web services means a successful presence on the web. Failure rates for the presence of a web site are considered on client sides errors using RFC2068. Data were collected from some host via the internet.