• 가정과삶의질연구
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• 제15권2호
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• pp.33-44
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• 1997

The purpose of this study was to investigate the relationship between time perception and information search behavior of consumers. Data were obtained from 380 married people living in Seoul: 141 men and 239 women. Time perception was identified in two ways: one with time pressure and the other with time inclination, Information search behavior divided into three parts: search time search activity and content search. The results of this research indicated that there were significant relationship between consumer's time perception and each of information search behavior. The results of this study can be attributed to develop the efficient information search be attributed to dvelop the efficient information search behavior of consumers and to understand time perception variables related the consumer search behavior.

• 한국비블리아학회지
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• 제5권1호
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• pp.85-105
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• 1981

Information is an essential factor leading the rapid progress which is one of the distinguished characteristics in modem society. As more information is required and as more is supplied by individuals, governmental units, businesses, and educational institutions, the greater will be the requirement for efficient methods of communication. One possibility for improving the information dissemination process is to use computers. The capabilities of such machine are beginning to be used in the process of Information storage, retrieval and dissemination. An important problems, that must be carefully examined is whether one technique for information retrieval is better for worse than another. This paper examines problem of how to evaluate an information retrieval system. One specific approach is a cost accounting model for use in studying how to minimize the cost of operating a mechanized retrieval system. Through the use of cost analysis, the model provides a method for comparative evaluation between systems. The general cost accounting model of the literature retrieval system being designed by this study are given below. 1. The total cost accounting model of the literature retrieval system. The total cost of the literature retrieval system = (the cost per unit of user time X the amount of user time) + ( the cost per unit of system time X the amount of system time) 2. System cost accounting model system cost = (the pre-search system cost per unit of time X time) + (the search system cost per unit of time X time) + (the post search system cost per unit of time X time) 1) Pre-search system cost per unit of time = cost of channel per unit time + cost of central processing unit per unit time + cost of storage per unit time 2) Search system cost per unit of time = comparison cost + document representation cost. 3) Post-search system cost per unit of time. = cost of channel per unit time + cost of central processing unit per unit time + cost of storage per unit time 3. User cost accounting model Total user cost = [pre-search user cost per unit of time X (time + additional time) ] + [search user cost per unit of time X (time + additional time) ] + [post-search user cost per unit of time X (time + additional time) ].

• 대한산업공학회지
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• 제29권2호
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• pp.165-171
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• 2003

Visual search in an unstructured search field is a fruitful research area for computational modeling. Search models that describe relationship between search time and probability of target detection have been used for prediction of human search performance and provision of ideal goals for search training. Until recently, however, most of models were focused on detecting a single target in a search field, although, in practice, a search field includes multiple targets and search models for multiple targets may differ from search models for a single target. This study proposed a random search model for multiple targets, generalizing a random search model for a single target which is the most typical search model. To test this model, human search data were collected and compared with the model. This model well predicted human performance in visual search for multiple targets. This paper also proposed how to determine optimal stopping time in multiple-target search.

• Journal of information and communication convergence engineering
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• 제9권1호
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• pp.27-31
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• 2011

This paper describes the optimization of spectrum sensing in terms of the throughput of a cognitive radio (CR) system. Dealing with the optimization problem of spectrum sensing, this paper evaluates the throughput of a CR system by considering such situations as the penalty time of a channel search and incumbent user (IU) detection delay caused by a missed detection of an incumbent signal. Also, this paper suggests a serial channel search scheme as the search method for a vacant channel, and derives its mean channel search time by considering the penalty time due to the false alarm of a vacant channel search. The numerical results suggest the optimum sensing time of the channel search process using the derived mean channel search time of a serial channel search in the case of a sensing hardware structure with single radio frequency (RF) path. It also demonstrates that the average throughput is improved by two separate RF paths in spite of the hardware complexity of an RF receiver.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.13-16
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• 2004

This paper deals with a one-searcher multi-target search problem where targets with different detection priorities move in Markov processes in each discrete time over a given space search area, and the total number of search time intervals is fixed. A limited search resource is available in each search time interval and an exponential detection function is assumed. The searcher can obtain a target detection award, if detected, which represents the detection priority of target and is non-increasing with time. The objective is to establish the optimal search plan which allocates the search resource effort over the search areas in each time interval in order to maximize the total detection award. In the analysis, the given problem is decomposed into intervalwise individual search problems each being treated as a single stationary target problem for each time interval. An associated iterative procedure is derived to solve a sequence of stationary target problems. The computational results show that the proposed algorithm guarantees optimality.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2006년도 추계학술대회
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• pp.57-59
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• 2006

The purpose of search problem is to maximize the probability of target detection as limited search capability. Especially, as elapsing of time at a point of time of initial information received the target detection rate for searching an expected location due to a moving target such that wrecked ship or submarine decrease in these problems. The algorithm of search problem to a moving target having similar property of above targets should solve the search route as quickly as possible. In existing studies, they have a limit of applying in practice due to increasing computation time required by problem size (i.e., number of search area, search time). In this study, we provide that it takes more reasonable computation time than preceding studies even though extending a problem size practically using an approximate computation of probability.

• Journal of information and communication convergence engineering
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• 제5권3호
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• pp.239-244
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• 2007

In the telematics system, a reasonable path search time should be guaranteed from a great number of user's queries, even though the optimal path with minimized travel time might be continuously changed by the traffic flows. Thus, the path search method should consider traffic flows of the roads and the search time as well. However, the existing path search methods are not able to cope efficiently with the change of the traffic flows and to search rapidly paths simultaneously. This paper proposes a new path search method for fast computation. It also reflects the traffic flows efficiently. Especially, in order to simplify the computation of variable heuristic values, it employs a simplification method for estimating values of traffic-adaptable heuristics. The experiments are carried out with the $A^*$ algorithm and the proposed method in terms of the execution time, the number of node accesses and the accuracy. The results obtained from the experiments show that the method achieves very fast execution time and the reasonable accuracy as well.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권4호
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• pp.472-476
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• 2010

최근 주요 검색 엔진들의 인덱스들이 굉장한 비율로 성장하는 것처럼, 수직형 검색 서비스들은 사용자가 원하는 것을 찾을 수 있도록 지원할 수 있다. 실시간 검색은 주어진 주제를 쉽게 찾아낼 수 있기 때문에 매우 유용하다. 본 논문에서는 고성능 실시간 검색 시스템을 구현하기 위한 새로운 구조를 설계하였다. 전체적인 시스템은 실시간 검색의 특징을 기반으로, 크게 수집 시스템과 검색 시스템의 두 부분으로 나뉘어진다. 본 논문의 평가 결과에서 제안한 구조가 Replication Overhead 값을 유지하면서 실시간 검색에 있어 투명한 확장성을 제공할 수 있음을 확인하였다.

• 지능정보연구
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• 제16권4호
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• pp.21-41
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• 2010

본 논문은 다양한 사용자의 개인적 검색요구를 충족시키지 못하는 기존 검색시스템의 문제점을 해결하기 위해 사용자의 묵시적 피드백을 이용한 적응형 사용자 기호정보 기반의 개인화 검색을 실현하고, 검색결과에 대한 실시간 필터링을 통해 사용자에게 적합한 검색 결과를 제공하는 시스템을 제안한다. 기존의 검색 시스템들은 검색의도의 불확실성 때문에 사용자의 검색실패율이 높다. 검색 의도의 불확실성은 동일한 사용자가 "java"와 같은 다의어에 대해 동일한 질의어를 사용하더라도 다른 검색 결과를 원할 수 있다는 것이며, 단어의 수가 적을수록 불확실성은 가중될 것이다. 실시간 필터링은 사용자의 도메인 지정여부에 따라 주어진 도메인에 해당하는 웹문서들만 추출하거나, 적절한 도메인을 추론하고 해당하는 웹문서들만 검색 결과로 보여주는 것으로, 일반적인 디렉토리 검색과 유사하지만 모든 웹문서에 대해 이루어진다는 것과 실시간으로 분류된다는 것이 다르다. 실시간 필터링을 개인화에 활용함으로써 검색 결과의 수를 줄이고 검색만족도를 개선했다. 본 논문에서 생성한 기호정보파일은 계층적 구조로 이루어지며, 상황정보의 반영이 가능하기 때문에 의도의 불확실성을 해결 할 수 있다. 또한 사용자의 도메인별 웹문서 검색 동작을 효과적으로 추적(track) 할 수 있으며, 사용자의 기호 변화를 적절하게 알아낼 수 있다. 각 사용자 식별을 위해 IP address를 사용했으며, 기호정보파일은 사용자의 검색 행동에 대한 관찰을 기반으로 지속적으로 갱신된다. 또한 사용자의 검색결과에 대한 행동 관찰을 통해, 사용자 기호를 인지하고, 기호정보를 동적으로 반영했으며, 검색결과에 대한 만족도를 측정했다. 기호정보파일과 반영비율은 사용자가 검색을 수행할 때 시스템에 의해 생성되거나 갱신된다. 실험결과 적응형 사용자 기호정보파일과 실시간 필터링을 함께 사용함으로써, 상위 10개의 검색결과 중 평균 4.7개의 결과들에 대해 만족하는 것으로 나타났으며, 이는 구글의 결과에 비해 약 23.2% 향상된 만족도를 나타내었다.

• 디지털융복합연구
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• 제17권12호
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• pp.255-260
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• 2019

실시간검색어는 실시간으로 관심이 급상승하는 검색어에 대한 것으로 한정될 뿐 아니라 포털사이트마다 순위 차이가 있으므로 지속가능성을 파악하기 힘든 한계를 가지고 있다. 실시간검색어에 대한 지속가능성을 평가하는 것은 이러한 한계를 극복하고 예측가능성을 제공해준다는 측면에서 그 의미가 크다. 특히 한 달 이상 지속되는 장기 지속 검색어의 경우 사회적으로 관심이 오래 지속된 이슈로서 가치가 높다. 따라서 본 논문에서는 실시간검색어 순위에 기반한 관심도와 실시간검색어의 지속주수, 지속일수, 지속시간에 기반을 둔 지속도를 각 포털사이트 및 통합 포털사이트 별로 파악한 다음, 관심도와 지속도가 높은 것을 기준으로 지속가능성을 평가하여, 장기 지속가능성이 높은 실시간이슈를 도출하는 방법을 제시하고자 한다.