• Journal of the Korean BIBLIA Society for library and Information Science
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• v.5 no.1
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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) ].

• Journal of the Ergonomics Society of Korea
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• v.31 no.6
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• pp.705-713
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• 2012

Objective: The aim of this study is to predict human visual target search using ACT-R cognitive architecture in real scene images. Background: Human uses both the method of bottom-up and top-down process at the same time using characteristics of image itself and knowledge about images. Modeling of human visual search also needs to include both processes. Method: In this study, visual target object search performance in real scene images was analyzed comparing experimental data and result of ACT-R model. 10 students participated in this experiment and the model was simulated ten times. This experiment was conducted in two conditions, indoor images and outdoor images. The ACT-R model considering the first saccade region through calculating the saliency map and spatial layout was established. Proposed model in this study used the guide of visual search and adopted visual search strategies according to the guide. Results: In the analysis results, no significant difference on performance time between model prediction and empirical data was found. Conclusion: The proposed ACT-R model is able to predict the human visual search process in real scene images using salience map and spatial layout. Application: This study is useful in conducting model-based evaluation in visual search, particularly in real images. Also, this study is able to adopt in diverse image processing program such as helper of the visually impaired.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.8
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• pp.737-743
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• 2009

Design optimization process and results of Loop Heat Pipe(LHP) using Tabu Search have been presented in this study. An objective of optimization is to reduce a mass of the LHP with satisfying operating temperature of a Lithium Ion battery onboard an aircraft. The battery is assumed to be used as power supply of air borne high energy laser system because of its high specific energy. The analytical models are based on a steady state mathematical model and the design optimization is performed using a Meta Model and Tabu Search. As an optimization results, the Tabu search algorithm guarantees global optimum with small computation time. Due to searching by random numbers, initial value is dominant factor to search global optimum. The optimization process could reduce the mass of the LHP which express the same performance as an published LHP.

• Knowledge Management Research
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• v.21 no.4
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• pp.109-127
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• 2020

This study empirically investigates the effects of information search on new product development (NPD) process and performance with a sample of 82 NPD projects in 5 firms. The information search is consisted of general sources, internal sources, and external sources. The performance is consisted of technological and market performance. Findings show that information search from internal sources increases the technological knowledge of the NPD team, and information search from external sources increases the market knowledge of the NPD team. The technological and market knowledge of the NPD team increases its technical performance respectively. Only the market knowledge of the NPD team increases its market performance. Overall, the technological knowledge of the NPD team fully mediates the relationship between the information search from internal sources and its technical performance. The market knowledge of the NPD team fully mediates the relationship between the information search from external sources and its technical performance, and the relationship between the information search from external sources and its market performance. There is no other significant mediation relationships between the information searches and the performances. Implications of the research findings are discussed, and recommendation for future research are provided.

• Industrial Engineering and Management Systems
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• v.8 no.3
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• pp.139-147
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• 2009

Control charts are used to distinguish between chance and assignable causes in the variability of quality characteristics. When a control chart signals that an assignable cause is present, process engineers must initiate a search for the assignable cause of the process disturbance. Identifying the time of a process change could lead to simplifying the search for the assignable cause and less process down time, as well as help to reduce the probability of incorrectly identifying the assignable cause. The change point estimation by likelihood theory and the built-in change point estimation in a control chart have been discussed until now. In this article, we discuss two kinds of process change point estimation when the CUSUM ($\bar{x}$, s) control chart for monitoring process mean and variance simultaneously is operated. Throughout some numerical experiments about the performance of the change point estimation, the change point estimation techniques in the CUSUM ($\bar{x}$, s) control chart are considered.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.4
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• pp.239-267
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• 2022

In this study, the adolescents' perception of the Information Search Process(ISP); their anxiety and the need for intervention during the process were investigated based on Kuhlthau's ISP model, and the relationship among the factors was analyzed with structural equations. In addition, the effectiveness of scaffolding strategy to the experimental group during the class was verified. The main findings are as follows. First, as a result of exploring the anxiety felt by learners and the need for intervention in the information search process, it was found that the presentation stage had a significant effect on the anxiety, and the collection, presentation, and assessment stages had significant effects on the need for intervention. Second, as a result of controlling each variable to investigate the anxiety felt by learners and necessity of intervention in the information search process, it was confirmed that among the demographic variables, the difference between the first graders and the second ones was significant; and the difference in the metropolitan area was more significant than that in the Gangwon province. Third, as a result of paired t-test and covariance analysis on the control group and the experimental group, it was confirmed that the anxiety and need for intervention of the experimental group were statistically significantly reduced. The significance of this study lies in the point that it presents a practical basis for applying scaffolding strategies appropriate to information search process in the field of education.

• Journal of KIISE:Databases
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• v.33 no.7
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• pp.754-765
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• 2006

In XML keyword search, a search result is defined as a set of the smallest elements (i.e., least common ancestors) containing all query keywords and a granularity of indexing is an XML element instead of a document. Under the conventional index structure, all least common ancestors produced by the combination of the elements, each of which contains a query keyword, are considered as a search result. In this paper, to avoid unnecessary operations of producing the least common ancestors and reduce query process time, we describe a way to construct a partitioned index composed of several partitions and produce a search result by merging those partitions if necessary. When a search result is restricted to be composed of the least common ancestors whose depths are higher than a given minimum depth, under the proposed partitioned index structure, search systems can reduce the query process time by considering only combinations of the elements belonging to the same partition. Even though the minimum depth is not given or unknown, search systems can obtain a search result with the partitioned index, which requires the same query process time to obtain the search result with non-partitioned index. Our experiment was conducted with the XML documents provided by the DBLP site and INEX2003, and the partitioned index could reduce a substantial amount of query processing time when the minimum depth is given.

• Journal of the Korean Society for information Management
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• v.33 no.3
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• pp.177-193
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• 2016

This study aims to analyze physicians' online information search process to solve the clinical questions at the point of care. To achieve this purpose, ten university hospital-based physicians participated in-depth interviews and observation studies. Based on Wilson's problem solving process, this study analyzed the characteristics of each information search stage and efficiency of online searching. The results showed that participants tend to relatively immediately formulate their clinical questions. However, basic searching strategies were only used and a few preferred information sources were chosen. However, average satisfaction degree of online searching appeared high with 5.7 (7 Likert-scale) and problem-solving index increased after searching. As physicians are likely to use well organized and evidenced-based credible information easily, it implies the needs for an integrated search system within the electronic medical record (EMR). In addition, as other online resources' awareness is lower comparing Google and PubMed, active promotions and training of other resources are needed.

• Industrial Engineering and Management Systems
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• v.8 no.3
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• pp.171-180
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• 2009

Population learning algorithm (PLA) is a population-based method that was inspired by the similarities to the phenomenon of social education process in which a diminishing number of individuals enter an increasing number of learning stages. The study aims to develop a framework that repeatedly applying the PLA to solve the discrete resource constrained project scheduling problem with two objectives: minimizing project makespan and renewable resource availability, which are two most common concerns of management when a project is being executed. The PLA looping framework will provide a number of near Pareto optimal schedules for the management to make a choice. Different improvement schemes and learning procedures are applied at different stages of the process. The process gradually becomes more and more sophisticated and time consuming as there are less and less individuals to be taught. An experiment with ProGen generated instances was conducted, and the results demonstrated that the looping framework using PLA outperforms those using genetic local search, particle swarm optimization with local search, scatter search, as well as biased sampling multi-pass algorithm, in terms of several performance measures of proximity. However, the diversity using spread metric does not reveal any significant difference between these five looping algorithms.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.2
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• pp.207-217
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• 1993

In this paper, knowing a priori probability of phase offset between transmitted codes and reference codes in the receiver, we construct the state diagram of acquisition process of the direct sequence spread-spectrum communication system using the expanding window search. The scannings are performed from the cell with higher probability code epoch synchronization to that with lower one. We expand window size from initial value by r times of its previous size in each search, construct the corresponding the state diagrams, and derive average synchronization time using the Markov process and Mason's gain formula. Average synchronization times versus number of search n and detection probability $P_d$ are calculated.