• Title/Summary/Keyword: A* search

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Efficient Bidirectional Search Algorithm for Optimal Route (최적 경로를 보장하는 효율적인 양방향 탐색 알고리즘)

  • 황보택근
    • Journal of Korea Multimedia Society
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    • v.5 no.6
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    • pp.745-752
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    • 2002
  • A* algorithm is widely used in optimal car route search which is a kind of informed search, since the locations of starting and ending points are known a priori. Unidirectional A* algorithm requires considerable search time but guarantees a optimal path, bidirectional A* algorithm does not guarantee a optimal path and takes even longer search time than unidirectional search to guarantee a optimal path. In this paper, a new bidirectional A* algorithm which requites less search time and guarantees a optimal path is proposed. To evaluate the efficiency of the proposed algorithm, several experiments are conducted in real road map and the results show that the algorithm is very effective in terms of finding a optimal path and search time.

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Concept Network-based Personalized Web Search Systems (개념 네트워크 기반 사용자 인지형 웹 검색 시스템)

  • Yune, Hong-June;Noh, Joon-Ho;Kim, Han-Joon;Lee, Byung-Jeong;Kang, Soo-Yong;Chang, Jae-Young
    • Journal of Internet Computing and Services
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    • v.12 no.2
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    • pp.63-73
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    • 2011
  • In general, conventional search engines provide the same search results for the same queries of users, and however such techniques do not consider users' characteristics. To overcome this problem, we need a new way of personalized search which returns customized search results according to users' preference. In this paper, we propose a concept network profile-based personalized web search system in which the concept network is developed for accumulating users' characteristics. The concept network-based user profile is used to expand initial search queries to achieve personalized search. The concept network is a network structure of concepts where each concept is generated whenever each query is submitted, and it can be defined as a set of keywords extracted from the selected documents. Furthermore, we have improved the concept networks by augmenting intent keywords of each concept with a set of classification tags, called folksonomy, assigned to each document. For an additional personalized search technique, we propose a new re-ranking method that analayzes the degree of overlapped search results.

A Hybrid of Evolutionary Search and Local Heuristic Search for Combinatorial Optimization Problems

  • Park, Lae-Jeong;Park, Cheol-Hoon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.1 no.1
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    • pp.6-12
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    • 2001
  • Evolutionary algorithms(EAs) have been successfully applied to many combinatorial optimization problems of various engineering fields. Recently, some comparative studies of EAs with other stochastic search algorithms have, however, shown that they are similar to, or even are not comparable to other heuristic search. In this paper, a new hybrid evolutionary algorithm utilizing a new local heuristic search, for combinatorial optimization problems, is presented. The new intelligent local heuristic search is described, and the behavior of the hybrid search algorithm is investigated on two well-known problems: traveling salesman problems (TSPs), and quadratic assignment problems(QAPs). The results indicate that the proposed hybrid is able to produce solutions of high quality compared with some of evolutionary and simulated annealing.

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A Study on the Trend and Meaning of Searching for Herbal Medicines in Online Portal Using Naver DataLab Search Trend Service (네이버 데이터랩 검색어 트렌드 서비스를 이용한 온라인 포털에서의 한약재 검색 트렌드와 의미에 대한 고찰)

  • Kim, Young-Sik;Lee, Seungho
    • The Korea Journal of Herbology
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    • v.36 no.5
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    • pp.1-14
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    • 2021
  • Objectives : From January 2020, when the first confirmed case of COVID-19 in Korea, the use of health information using the Internet is expected to increase. It is expected that there will be a significant change in the general public's interest in Korean herbal medicines for health care. Therefore, in this study, we tried to confirm the change in the search trend of Korean herbal medicines after the COVID-19 epidemic. Methods : Using the "Naver DataLab (http://datalab.naver.com)" service of a Korean portal site Naver, search volume was investigated with 606 Korean herbal medicines as keywords. The search period was from January 2020, right after the onset of COVID-19, to June 2021. The search results were sorted by the peak search volume and the total search volume. Results : 'Cheonsangap (천산갑, 穿山甲, Manitis Squama)' was the most searched Korean herbal medicine in the peak search volume and total search volume with least bias. Conclusions : The problem of supply and demand of Korean herbal medicines of high public interest was identified. Broadcasting and media exposure were the factors that had a big impact on the search volume for Korean herbal medicines. As it was confirmed that the search volume for Korean herbal medicines increased rapidly due to media exposure, it is necessary to provide correct information about Korean herbal medicines, improve public awareness, and manage stable supply and demand based on continuous search trend monitoring.

Subband PRI analysis algorithm (Subband PRI 분석 알고리즘)

  • 윤원식
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.6
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    • pp.1425-1429
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    • 1996
  • A conventional sequence search algorithm for PRI analysis occurs the harmonic problem under missing pulses. An improved PRI analysis algorithm is proposedto remedy the harmonic problem. After dividing an overall PRI range into subbands withoug harmonic, a sequence search is done into forward and backward in time. The proposed algorithm increases the preformance compared with that of conventional sequence search algorithm.

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Likelihood search method with variable division search

  • Koga, Masaru;Hirasawa, Kotaro;Murata, Junichi;Ohbayashi, Masanao
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.14-17
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    • 1995
  • Various methods and techniques have been proposed for solving optimization problems; the methods have been applied to various practical problems. However the methods have demerits. The demerits which should be covered are, for example, falling into local minima, or, a slow convergence speed to optimal points. In this paper, Likelihood Search Method (L.S.M.) is proposed for searching for a global optimum systematically and effectively in a single framework, which is not a combination of different methods. The L.S.M. is a sort of a random search method (R.S.M.) and thus can get out of local minima. However exploitation of gradient information makes the L.S.M. superior in convergence speed to the commonly used R.S.M..

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Intelligent Search System for Comparative Searches (비교 검색을 위한 지능형 검색 시스템)

  • Yangjin Seo;Sangyong Han
    • Proceedings of the CALSEC Conference
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    • 2001.08a
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    • pp.625-629
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    • 2001
  • A cyber shopping mall is a place where consumers acquire product information, and make purchase decisions in the cyber space. Even though it offers many advantages over traditional malls, there are still several limitations to do shopping in an existing cyber mall. One of these limitations is the absence of an efficient shopping aid to compare multiple items from multiple malls. Existing search systems usually support a keyword search with limited conditions. Consumers spend lots of their time to compare multiple alternatives from search results. In this paper, we propose an intelligent product search system. There are two main features in our system. The first one is a full support of comparison shopping with multiple perspectives based on commercial search engines. The second one is an enhancement to the shopping aid based on a new concept of Shopping AssistanT. Our system is implemented in Visual Basic and PERL, and experimental results show a satisfactory performance.

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Development of a Stock Auto-Trading System using Condition-Search

  • Gyu-Sang Cho
    • International Journal of Internet, Broadcasting and Communication
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    • v.15 no.3
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    • pp.203-210
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    • 2023
  • In this paper, we develope a stock trading system that automatically buy and sell stocks in Kiwoom Securities' HTS system. The system is made by using Kiwoom Open API+ with the Python programming language. A trading strategy is based on an enhanced system query method called a Condition-Search. The Condition-Search script is edited in Kiwoom Hero 4 HTS and the script is stored in the Kiwoom server. The Condition-Search script has the advantage of being easy to change the trading strategy because it can be modified and changed as needed. In the HTS system, up to ten Condition-Search scripts are supported, so it is possible to apply various trading methods. But there are some restrictions on transactions and Condition-Search in Kiwoom Open API+. To avoid one problem that has transaction number and frequency are restricted, a method of adjusting the time interval between transactions is applied and the other problem that do not support a threading technique is solved by an IPC(Inter-Process Communication) with multiple login IDs.

A Study on the Information Search, Information Use and Search Outcome of Adolescent Consumers -Focus on Clothing Purchase Behavior- (청소년 소비자의 정보탐색, 정보활용 및 탐색성과에 대한 인과분석 -의류 구매를 중심으로-)

  • Heo, Jin-Young;Kim, Young-Seen
    • Korean Journal of Human Ecology
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    • v.7 no.1
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    • pp.61-74
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    • 1998
  • The purpose of this study is to investigate the information search, information use and search outcomes. 420 students in Chungnam and Taejon area were surveyed. Questionnaire survey method and multiple regression and path analysis were used. Some major conclusions were as follows: 1) The levels of the information search, information use and search outcomes were relatively low. 2) The volumes of information search and the contents of information were mainly affected by psycho-behavioral variables. 3) The level of information use was affected by the content of information, desire to seek information, involvement, and previous knowledge. 4) The search outcome was affected positively by the information use, involvement, volume of information search, desire to seek information, and perceived risk. 5) The volume of information search and the information use were the parameter of the search outcomes.

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A Search Interval Limitation Technique for Improved Search Performance of CNN (연속 최근접 이웃(CNN) 탐색의 성능향상을 위한 탐색구간 제한기법)

  • Han, Seok;Oh, Duk-Shin;Kim, Jong-Wan
    • Journal of Internet Computing and Services
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    • v.9 no.3
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    • pp.1-8
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    • 2008
  • With growing interest in location-based service (LBS), there is increasing necessity for nearest neighbor (NN) search through query while the user is moving. NN search in such a dynamic environment has been performed through the repeated applicaton of the NN method to the search segment, but this increases search cost because of unnecessary redundant calculation. We propose slabbed continuous nearest neighbor (Slabbed_CNN) search, which is a new method that searches CNN in the search segment while moving, Slabbed_CNN reduces calculation costs and provides faster services than existing CNN by reducing the search area and calculation cost of the existing CNN method through reducing the search segment using slabs.

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