• Journal of KIISE:Databases
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• v.33 no.4
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• pp.423-436
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• 2006

In recent years, publish-subscribe (pub-sub) systems based on XML document filtering have received much attention. In a typical pub-sub system, subscribing users specify their interest in profiles expressed in the XPath language, and each new content is matched against the user profiles so that the content is delivered only to the interested subscribers. As the number of subscribed users and their profiles can grow very large, the scalability of the system is critical to the success of pub-sub services. In this paper, we propose a novel scalable filtering system called FiST(Filtering by Sequencing Twigs) that transforms twig patterns expressed in XPath and XML documents into sequences using Prufer's method. As a consequence, instead of matching linear paths of twig patterns individually and merging the matches during post-processing, FiST performs holistic matching of twig patterns with incoming documents. FiST organizes the sequences into a dynamic hash based index for efficient filtering. We demonstrate that our holistic matching approach yields lower filtering cost and good scalability under various situations.

• Journal of IKEEE
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• v.25 no.2
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• pp.291-301
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• 2021

OPC UA at the control and field level does not provide enough performance to replace the field bus. The OPC Foundation aims for a real-time and connection-less mechanism, and has added the OPC UA publish-subscribe model, a new specification that supports broker functions such as MQTT and AMQP, as the OPC UA Part 14 standard. This paper is about a gateway for interoperability between OPC UA publisher with the addition of OPC UA Part14 standard and DDS subscribers. Raspberry Pi 4 is used for the gateway proposed in this paper, and OpenDDS, an open source, is used for DDS. OPC UA publish-subscribe module used A-Open62541 publish-subscribe module, which additionally implements functions not provided by the corresponding source based on Open62541 publish-subscribe open source.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.535-542
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• 2023

This study attempted to identify various variables that affect satisfaction and continued use intention of the subscription economy services. Through previous research studies, individual characteristics and service characteristic variables were considered together. Finally, use motivation, platform characteristic factors, and product and service characteristic factors were classified and examined. As a result of the study, the motive for using the service that affects the satisfaction of the subscription economy service was found to be functional hedonic, and economic motive, and platform recency and convenience, economic utility, and perceived personalization had a positive effect. Functional and hedonic motives and convenience showed positive influences on continued use intention, while social motives showed negative influences. In addition, it was confirmed that economic motivation, platform recency, economic utility, and perceived personalization showed a positive influence on the intention to continued use intention by mediating satisfaction with subscription economy services.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.1571-1574
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• 2010

최근 자료 송수신을 위한 분산 컴퓨팅 시스템들이 다양하게 연구되고 있다. 특히 센서를 이용하는 임베디드 어플리케이션들을 위한 분산 시스템들은 다양한 방면으로 연구되고 있다. 그 중 분산 미들웨어는 다양한 하드웨어 시스템과 응용 시스템 중간에 존재하며 유기적인 연결을 돕는 역할을 해왔다. 분산 미들웨어는 크게 원격 객체 관리를 위한 서버-클라이언트 모델, 메시지 패싱을 목적으로 하는 메시지 패싱 모델, 자료 분배를 목적으로 하는 출반-구독 모델로 나눌 수 있다. 이중출판-구독 모델은 원하는 데이터를 선택하여 다양한 수신 단말에 전송하기에 최적화된 구조를 지닌다. 본 논문에서는 대표적인 출판-구독 모델인 Data Distribution Service 를 소개하고 특정 상황에서 발생할 수 있는 네트워크 집중화를 막기 위해 오버레이 네트워크를 이용하는 기법을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.04a
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• pp.230-233
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• 2010

최근 분산된 노드들 간의 자료를 송수신하는 임베디드 어플리케이션들이 증가함에 따라 이를 지원하기 위한 분산 미들웨어도 함께 발전하고 있다. 분산미들웨어는 원격 객체 관리를 위한 클라이언트-서버 모델, 큐를 이용한 메시지 전송을 목적으로 하는 메시지 패싱 모델, 분산 컴퓨팅 환경에서 자료의 전송을 목적으로 하는 출판-구독 모델이라는 3가지 모델로 분류 된다. 본 논문에서는 3가지 분산 미들웨어 모델들에 대하여 살펴보고 출판-구독 모델의 대표적 분산미들웨어인 Data Distribution Service를 소개한다. 또한 출판-구독 모델이 단말 간 P2P를 지원함에 따라 생기는 문제점인 과다한 트래픽을 해결하기 위해 자료들을 그룹화 시켜 전송하거나 특정 토픽에 관련된 자료들을 미리 예약된 채널을 통해 전송하는 기법들을 제안하고 일반 DDS와 비교를 통해 그 효과를 예측해본다.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.5
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• pp.153-164
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• 2016

It is critical for adolescents to foster self-efficacy, creativity, and adventurous spirit as well as plans for appropriate career path in order to become good members of society. During this adolescent period, newspapers will be a good learning material as they deliver various and timely information in refined language. In this paper, we analyzed the impact of NIE on development of self-efficacy, awareness of career path, and entrepreneurship through comparing adolescents who regularly read newspapers with those who do not. We came up with the following result after analysis of surveys (with a sample size of 283) that targeted middle school and higher grade elementary school students across Korea. We confirmed that reading newspapers has a positive impact on development of self-efficacy, awareness of career path, and entrepreneurship. More specifically, reading newspapers regularly has a positive impact on development of self-efficacy that subsequently has a positive impact on development of awareness of career path and entrepreneurship. Therefore, we found that simply reading newspapers regularly has a positive impact on development of self-efficacy, awareness of career path, and entrepreneurship with no special programs utilizing the newspapers. This is because various information and opinions in newspapers help adolescents to develop their own views, improve understanding and awareness of career, and development of sociality including creativity and adventurous spirit. There is the meaning as the first research that this research checks what the NIE of the adolescents affects the positive impact to not only the self-efficacy and career awareness but also entrepreneurship.

• Journal of agricultural medicine and community health
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• v.25 no.2
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• pp.379-395
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• 2000

This questionnaire survey was conducted to evaluate the impact of health newsletter and related factors in the rural area. The Subjects were 354 individuals of 45 years of age and over, living in Chonnam province. The results of this study were as follows: The 225 surveyed persons (64%) recognized the health newsletter, and 196 persons (55%) read it least once and more. Newsletter-recogniton related factors were sex and age. Newsletter-reading related factors were chronic disease and sex. And Newsletter-reading pattern was determined by age and education level. 147 persons(75.8%) reported that they had got the important health information from newletter, and 76 persons(39.8%) reported the behavior change. The quiz scores of hypertension and health care in summer were higher in the persons of newsletter-recognition than in persons of non-recognition. The quiz score of hypertension was not higher in newsletter reader than non-reader, but that of health care in summer was higher in newsletter reader than in non-reader.

• Journal of Venture Innovation
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• v.6 no.1
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• pp.1-16
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• 2023

Due to the progress of the 4th industrial revolution and the COVID-19 pandemic, the subscription economy was rapidly expanding. In particular, the subscription economy was expected to expand further as the servicing of products(servitization) rapidly progresses. In this study, we tried to empirically analyze the factors that promote and hinder the spread of the subscription economy from the consumer's point of view. To this end, based on the Service Profit Chain (SPC) model, which identified mechanisms leading from quality to satisfaction, loyalty, and performance, a research model was established by combining the framework of the Value-based Adoption Model (VAM), which covers both benefit and sacrifice factors. Usefulness and convenience were derived as benefit factors, and perceived risks and perceived costs were derived as sacrifice factors. The effects of these factors on satisfaction and continuous use intention were analyzed. For empirical analysis, a survey was conducted targeting people who have experience in subscription economy, and 300 effective samples were analyzed. The analysis was performed as a structural equation model using AMOS 24. As a result of the empirical study, it was found that convenience had a significant positive (+) effect on satisfaction. Perceived risk and perceived cost were analyzed to have a negative (-) effect on satisfaction. On the other hand, usefulness was found to have no significant effect on satisfaction. The influences affecting satisfaction were in the order of perceived cost, convenience, and perceived risk. Satisfaction was found to have a significant positive (+) effect on continuous use intention. The results of this study were considered meaningful in that they broadened the horizons of research by combining existing validated models at the academic level and testing their validity, and found that perceived cost was still an important factor at the practical level.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.3
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• pp.1-11
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• 2024

Content is now recognized as a key resource to sustain competitive advantage in the OTT market and for e-commerce companies. Coupang is pursuing a content growth strategy to maximize the lock-in effect that binds consumers to the subscription economy and its ecosystem. Given this background, this study aims to explain Coupang's content growth momentum through a case study method and examine Coupang's content strategy in detail. Based on this, this study describes Coupang's content growth strategy in detail and confirms that Coupang differentiates its content from the competition by focusing on sports and low prices to build a lock-in effect in the subscription economy. As a result, we can summarize that the purpose of Coupang's content strategy is to build a lock-in effect for the subscription economy based on content differentiation focused on sports, a bundle strategy linked to e-commerce, and a low-cost strategy. This study contributes to the field of venture creation research by carefully analyzing how Coupang grew from a venture firm to a Decacorn corporation and developed the influence of its content in a completely different industry, and systematically explains the importance of content strategy in strengthening the lock-in effect for the subscription economy. Future research should compare the impact of content strategy of venture and startups in the contents industry to broaden the scope of research in the field and suggest deeper lessons learned.

• 월간 기계설비
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• no.3 s.200
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• pp.63-66
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• 2007

대한설비건설협회(회장 박종학)는 월간「설비건설」지령 200호를 맞아 월간「설비건설」의 구독현황을 알아보기 위해 전국 대의원 회원사를 대상으로 2007년 1월 23일부터 2월 5일까지 14일간“월간「설비건설」구독 실태 조사”를 실시했다. 이번 설문조사는 월간「설비건설」이 명실상부한 국내 유일의 설비업계 전문지로서의 위상을 높이기 위해 회원사의 의견을 취합하여 편집발전을 위한 자료로 활용코자 실시한 것이다.