• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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• pp.488-491
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• 1995

The paper presents a new global maximum search method for multimodal unknown functions of two variables. The search method is composed of two stages and sequentially samples the candidate point in a subdomain selected using a priority function in each stage. The search domain is auto-similarly divided into triangular subdomains, or cells, during the search process. A measure of accuracy of local maximum search is introduced to check if a local search has converged to a specified accuracy or the maximum of a local peak cannot be the global maximum. A criterion for switching from the first to the second stage, is proposed using a ratio of the observed peak width to the largest cell in the domain. By numerical simulations, the required number of trials is evaluated for some function models with different peak parameters, and the switching criterion is optimally determined. The results show that the proposed method obtains global maximum points with certainty and saves largely computation time even for functions with extremely steep peaks.

• 정보관리학회지
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• 제26권4호
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• pp.93-112
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• 2009

최근 정보검색 환경은 검색 2.0으로 대표되는 차세대 검색서비스에 대한 논의들이 활발해지고 있다. 따라서 이 연구에서는 정보검색의 발전과 진화에 대한 다양한 논의들을 토대로 정보검색의 발전 과정을 구분하였다. 그리고 현재 거론되고 있는 차세대 검색서비스의 등장 배경, 주요 개념, 그리고 관련 사례와 속성을 파악하였으며, 이러한 속성과 사례에 대한 데이터를 통해 차세대 검색서비스를 설명하는 핵심적인 키워드를 확인하기 위한 군집 분석을 수행하였다. 군집 분석의 결과 차세대 검색서비스를 대표하는 주요 키워드는 소셜 검색, 지능형 의미 검색, 그리고 관계기반 검색 등으로 나타났다.

• 한국정보시스템학회지:정보시스템연구
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• 제29권1호
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• pp.289-301
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• 2020

Purpose This study analyzes whether Internet search of cryptocurrency has a causal relationship to return and volatility of cryptocurrency. Design/methodology/approach Google Trend was used as a measure of the level of Internet search, and the parametric tests of Granger causality in the 1st moment and the 2nd moment were adopted as the analysis method. We used Bitcoin's dollar-based price, which is the No. 1 market value among cryptocurrency. Findings The results showed that the Internet search measured by Google Trends has a causal relationship to cryptocurrency in both average and volatility, while there is a difference in causality and its degree according to the search area and category that Google Trend user should set. Because the Granger causality is based on the improvement of prediction, the analysis results of this study indicate that Internet search can be used as a leading indicator in predicting return and volatility of cryptocurrency.

• 정보관리학회지
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• 제26권3호
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• pp.111-129
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• 2009

본 연구는 시각화 정보검색시스템이 실제 정보검색환경에서 이용자에게 원활하게 수용될 수 있는지에 대한 경험적인 분석을 제공하고자, 상용 학술데이터베이스의 텍스트 기반 검색과 비주얼검색의 사용성을 비교 평가하고, 실험순서에 따라 사용성 평가에 있어 차이가 있는지 분석하였다. 검색소요시간과 처리동작횟수에 있어서 텍스트 기반 검색이 비주얼검색보다 더 효율적인 것으로 나타났으며, 통계적으로 유의한 차이가 있는 것으로 나타났다. 또한 사용성에 대한 인식에 있어서도 텍스트 기반 검색이 비주얼 검색보다 전체적으로 더 높게 나타났으며 통계적으로 유의한 차이가 있는 것으로 나타났다.

• 중소기업연구
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• 제41권2호
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• pp.1-24
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• 2019

본 연구는 중소기업의 외부 정보 탐색전략이 기업의 혁신성과에 미치는 영향에 대해 파악하는 것을 목적으로 한다. 한국의 중소기업 3,398개를 대상으로 실증분석을 수행한 결과, 깊이 추구의 탐색전략과 범위 추구의 탐색전략은 상호 대체적 관계를 가지며, 이러한 대체적 관계는 기업이 협업경험을 보유할 때 약화되는 것으로 나타났다. 또한 두 유형의 탐색전략은 모두 기업의 혁신성과를 향상시켜 주지만, 깊이 추구 탐색전략이 범위 추구 탐색전략보다 상대적으로 더 큰 양의 영향을 미치는 것으로 나타났다. 그리고 범위 추구의 탐색전략을 실행하는 기업이 공식적인 정보보호 방안을 채택할 경우 탐색전략의 혁신성과에 대한 효과가 약화되는 것으로 나타났다.

• Journal of the Korean Statistical Society
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• 제19권1호
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• pp.15-23
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• 1990

The basic conditions for a parallel flats fraction to be a search design of resolution III.2 have been developed in Um (1980, 1981, 1983, 1984). A series of resolution III.2 search design for $3^n, n=4, 5, 6$ are presented in Um (1988). In this paper a resoultion III.3 search design for $3^4$ is presented.

• 한국정보시스템학회지:정보시스템연구
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• 제26권3호
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• pp.171-185
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• 2017

Purpose Recently, there has been an increase in attempts to analyze social phenomena, consumption trends, and consumption behavior through a vast amount of customer data such as web search traffic information and social buzz information in various fields such as flu prediction and real estate price prediction. Internet portal service providers such as google and naver are disclosing web search traffic information of online users as services such as google trends and naver trends. Academic and industry are paying attention to research on information search behavior and utilization of online users based on the web search traffic information. Although there are many studies predicting social phenomena, consumption trends, political polls, etc. based on web search traffic information, it is hard to find the research to explain and predict tourism demand and establish tourism policy using it. In this study, we try to use web search traffic information to explain the tourism demand for major cities in Gangwon-do, the representative tourist area in Korea, and to develop a nowcasting model for the demand. Design/methodology/approach In the first step, the literature review on travel demand and web search traffic was conducted in parallel in two directions. In the second stage, we conducted a qualitative research to confirm the information retrieval behavior of the traveler. In the next step, we extracted the representative tourist cities of Gangwon-do and confirmed which keywords were used for the search. In the fourth step, we collected tourist demand data to be used as a dependent variable and collected web search traffic information of each keyword to be used as an independent variable. In the fifth step, we set up a time series benchmark model, and added the web search traffic information to this model to confirm whether the prediction model improved. In the last stage, we analyze the prediction models that are finally selected as optimal and confirm whether the influence of the keywords on the prediction of travel demand. Findings This study has developed a tourism demand forecasting model of Gangwon-do, a representative tourist destination in Korea, by expanding and applying web search traffic information to tourism demand forecasting. We compared the existing time series model with the benchmarking model and confirmed the superiority of the proposed model. In addition, this study also confirms that web search traffic information has a positive correlation with travel demand and precedes it by one or two months, thereby asserting its suitability as a prediction model. Furthermore, by deriving search keywords that have a significant effect on tourism demand forecast for each city, representative characteristics of each region can be selected.

• Asia pacific journal of information systems
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• 제19권1호
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• pp.1-31
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• 2009

This paper empirically examines factors that potentially influence the success of a Web-based semantic search engine. A research model has been proposed that shows the impact of quality-related factors upon the effectiveness of a semantic search engine, based on DeLone and McLean's(2003) information systems success model. An empirical study has been conducted to test hypotheses formulated around the research model, and statistical methods were applied to analyze gathered data and draw conclusions. Implications for academics and practitioners are offered based on the findings of the study. The proposed model includes three quality dimensions of a Web-based semantic search engine-namely, information quality, system quality and service quality. These three dimensions each have measures designed to collectively assess the respective dimension. The model is intended to examine the relationship between measures of these quality dimensions and measures of two dependent constructs, including individuals' net benefit and user satisfaction. Individuals' net benefit was measured by the extent to which the user's information needs were adequately met, whereas user satisfaction was measured by a combination of the perceived satisfaction with search results and the perceived satisfaction with the overall system. A total of 23 hypotheses have been formulated around the model, and a questionnaire survey has been conducted using a functional semantic search website created by KT and Hakia, so as to collect data to validate the model. Copies of a questionnaire form were handed out in person to 160 research associates and employees working in the area of designing and developing semantic search engines. Those who received the form, 148 respondents returned valid responses. The survey form asked respondents to use the given website to answer questions concerning the system. The results of the empirical study have indicated that, of the three quality dimensions, information quality was found to have the strongest association with the effectiveness of a Web-based semantic search engine. This finding is consistent with the observation in the literature that the aspects of the information quality should serve as a basis for evaluating the search outcomes from a semantic search engine. Measures under the information quality dimension that have a positive effect on informational gratification and user satisfaction were found to be recall and currency. Under the system quality dimension, response time and interactivity, were positively related to informational gratification. On the other hand, only one measure under the service quality dimension, reliability was found to have a positive relationship with user satisfaction. The results were based on the seven hypotheses that have been accepted. One may wonder why 15 out of the 23 hypotheses have been rejected and question the theoretical soundness of the model. However, the correlations between independent variables and dependent variables came out to be fairly high. This suggests that the structural equation model yielded results inconsistent with those of coefficient analysis, because the structural equation model intends to examine the relationship among independent variables as well as the relationship between independent variables and dependent variables. The findings offer some useful implications for owners of a semantic search engine, as far as the design and maintenance of the website is concerned. First, the system should be designed to respond to the user's query as fast as possible. Also it should be designed to support the search process by recommending, revising, and choosing a search query, so as to maximize users' interactions with the system. Second, the system should present search results with maximum recall and currency to effectively meet the users' expectations. Third, it should be capable of providing online services in a reliable and trustworthy manner. Finally, effective increase in user satisfaction requires the improvement of quality factors associated with a semantic search engine, which would in turn help increase the informational gratification for users. The proposed model can serve as a useful framework for measuring the success of a Web-based semantic search engine. Applying the search engine success framework to the measurement of search engine effectiveness has the potential to provide an outline of what areas of a semantic search engine needs improvement, in order to better meet information needs of users. Further research will be needed to make this idea a reality.

• 한국정보통신학회논문지
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• 제20권5호
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• pp.880-886
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• 2016

인터넷 상에 많은 정보들이 발생하면서 검색 엔진은 사용자에게 필요한 흩어진 정보를 모아주는 중요한 역할을 하고 있다. 일부 검색 엔진에서는 검색어가 포함된 검색 결과 페이지뿐만 아니라 검색 결과 수도 함께 제공하고 있다. 구글 검색엔진에서 제공하는 검색 결과 수는 인터넷에서 해당 검색어에 대한 전체적인 추세를 파악하는데 활용될 수 있다. 본 논문에서는 구글 검색엔진에서 제공하는 검색결과 수를 효과적으로 관리할 수 있는 구글 검색엔진을 활용한 키워드 검색결과 수 관리 시스템을 설계하고 구현하고자 한다. 제안하는 시스템은 웹으로 작동하며 검색 에이전트, 저장 노드, 검색 노드로 구성되어 키워드 및 검색 결과 수를 관리하고 검색을 수행한다. 최종 검색 결과로는 검색 키워드, 검색 결과 수, 검색 결과 수를 활용하여 두 키워드의 거리를 계산하는 NGD(Normalized Google Distance)가 제공된다.

• 마케팅과학연구
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• 제15권3호
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• pp.93-116
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• 2005

본 연구는 온라인 쇼핑몰을 이용하는 소비자의 외부정보탐색노력에 영향을 미치는 요인을 정보경제학적 관점, 심리적 관점, 웹사이트 이론 관점으로 구분하여 탐색하였으며, 세 가지 이론을 통합하는 통합모델을 설계하였다. 통합 모델을 실증 분석한 결과, 온라인 쇼핑몰을 이용하여 제품을 구매하는 소비자의 외부정보탐색노력정도는 탐색동기, 탐색이익 등에 직접적인 영향을 받는 것으로 검증되었다. 한편 탐색동기는 탐색이익, 구매관여에 의하여 영향을 받는 것으로 검증되었다. 그리고, 탐색이익은 구매관여, 구조적간결성, 탐색의 편리성, 신뢰성에 직접적인 영향을 받으며, 탐색비용은 구매관여, 시간압박성, 구조적 간결성, 탐색의 편리성, 신뢰성에 직접적인 영향을 받는 것으로 확인되었다. 본 연구는 이와 같은 결과를 바탕으로 온라인 쇼핑몰의 관리에 대한 이론 및 관리적 시사점들을 제안하였다.