• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.8
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• pp.1110-1116
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• 2021

In this paper, we propose a conformal Ku-band data link antenna to ensure low RCS of stealth UAV. As a phased array antenna with electrical beam steering function, a transmitter and a receiver were designed and manufactured for FDD communication, respectively. Each antenna is designed as a 12*12 planar array antenna and has a function to form a uni-directional pattern and a bi-directional pattern through phase control of unit elements. The beam steering range is designed to be able to steer up to 60 degrees in theta direction and 360 degrees in the phi direction. As a result of manufacturing and measurement, the conformal type radome has low transmission loss and meets the required specifications including system performance. The feasibility of mounting the stealth UAV has been confirmed, and future research directions such as interworking of baseband devices and conversion to digital beam steering function are suggested.

• Asia pacific journal of information systems
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• v.7 no.3
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• pp.61-87
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• 1997

Recently, strategic information systems planning (SISP) has emerged as one of the necessities in 15 activities and organizational operations as a whole. Although various SISP researches have been done, in few studies have attention been given to the process employed in organizations to plan and implement SISP. To address SISP problems in terms of the process-oriented view, this paper employs a dynamic viewpoint on the basis of innovation-process model As a result of in-depth interviews with IS managers of nine Korean banks, this research found slightly different problems appear in each stage of the process. While problems cited in prior researches were observed, new ones are also appeared such as "finding out relative outsourcers" "political problems between functions which lead the process and others which alienated," the "necessity of steering committees, etc. Meanwhile, problems such as "top management concerns" or "cost," which suggested as significant problems in prior researches, appeared relatively insignificant This study has limitations as a qualitative and exploratory one. However, in view of further studies, the linkage between SISP practices and innovation process theory will allow researches linking characteristics of both fields. Furthermore, researches which view the SISP process as a comprehensive knowledge transfer process will be possible.

• Management & Information Systems Review
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• v.2
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• pp.267-294
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• 1998

Recently, self-efficacy is one of the critical constructs that have been found to influence human decisions about behavior selection and the performance associated with the selected behavior. The construct has been widely adopted and tested In the fields of social psychology and/or other behavioral sciences. In information systems field, however, it has been hardly studied, although computer self-efficacy could have been an important factor explaining and predicting human computer usage behaviors. From this perspective, main purposes of the study is to understand causal relation among the factors influencing computer self- efficacy, computer usage behavior and computer self-efficacy. The research reported in this study have several objectives; 1) to develop a measure of computer self-efficacy, 2) to Identify the factors influencing self-efficacy, and 3) to reveal the relationship between self-efficacy and computer usage behavior and then 4) to explain the causal model of computer self-efficacy. By reviewing the literature, past experience, others' use, encouragement by others, and anxiety are selected as the factors influencing computer self-efficacy. Four hypotheses concerning the relationship between each of the variables and computer self-efficacy are tested by LISREL. One more hypothesis about the relationship between computer self-efficacy and computer usage is also tested. The results show that computer self-efficacy is significantly influence by computer anxiety, encouragement by others, and computer experience, and that it is closely correlated with computer usage behavior.

• BMB Reports
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• v.37 no.1
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• pp.83-92
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• 2004

As a result of the enormous amount of information that has been collected with E. coli over the past half century (e.g. genome sequence, mutant phenotypes, metabolic and regulatory networks, etc.), we now have detailed knowledge about gene regulation, protein activity, several hundred enzyme reactions, metabolic pathways, macromolecular machines, and regulatory interactions for this model organism. However, understanding how all these processes interact to form a living cell will require further characterization, quantification, data integration, and mathematical modeling, systems biology. No organism can rival E. coli with respect to the amount of available basic information and experimental tractability for the technologies needed for this undertaking. A focused, systematic effort to understand the E. coli cell will accelerate the development of new post-genomic technologies, including both experimental and computational tools. It will also lead to new technologies that will be applicable to other organisms, from microbes to plants, animals, and humans. E. coli is not only the best studied free-living model organism, but is also an extensively used microbe for industrial applications, especially for the production of small molecules of interest. It is an excellent representative of Gram-negative commensal bacteria. E. coli may represent a perfect model organism for systems biology that is aimed at elucidating both its free-living and commensal life-styles, which should open the door to whole-cell modeling and simulation.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.2
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• pp.107-119
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• 2004

A study on the following parallel machine problem is addressed in this research. An order is completed only when a given number of processes (cycle) are repeated. Anew cycle is possible only upon the completion of the previous cycle. Orders are classified into job group according to product feature. For a machine to switch to a different job group from the currently processing one a major setup is required while a minor setup time is inserted in between two jobs of the same job group. The objective of the study is to find a schedule that minimizes total weighted tardiness. An initial solution is obtained by the RATCS(Restricted Apparent Tardiness Cost with Setup) rule, and a Tabu search is applied to improve the solution. Numerical examples are also presented.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.506-512
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• 2006

In this paper, we propose a lot-sizing and scheduling problem that seeks to minimize the sum of production cost and inventory cost over a given planning horizon while considering idle state of a machine in a batch production system. For this problem, we develop an integer programming model. And, we develop an efficient 2-phase heuristic algorithm to find a high quality feasible solution within reasonable time bounds. In the first phase, we seek to minimize the production cost by assigning batches to machines. Then, in the second phase, we find a production sequence of batches that reduces the inventory cost, while considering adding or deleting idle states between batches. Computational results show that the developed heuristic algorithm finds excellent feasible solutions within reasonable time bounds. Also, we could significantly reduce the total cost consisting of production cost and inventory cost by using the developed heuristic algorithm at a real manufacturing system that produces zinc alloys.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.127-133
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• 2006

Minimizing the total number of setup changes of a machine increases the throughput and improves the stability of a production process, and as a result enhances the product quality. In this context, we consider a new product-mix problem that minimizes the total number of setup changes while producing the required quantities of a product over a given planning horizon. For this problem, we develop a mixed integer programming model. Also, we develop an efficient heuristic algorithm to find a feasible solution of good quality within reasonable time bounds. Computational results show that the developed heuristic algorithm finds a feasible solution as good as the optimal solution in most test problems. Also, we developed a web based scheduling and monitoring system for a zinc alloy production process using the developed heuristic algorithm. By using this system, we could find a monthly zinc alloy production schedule that significantly reduces the total number of setup changes.

• The Journal of Information Systems
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• v.20 no.2
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• pp.207-228
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• 2011

IT governance is an integral part of enterprise governance and consists of the leadership, organizational structures, and processes that ensure organization's IT decision making for achieving organizational goal. Most firms have failed to resolve the balance in building IT governance. The challenge is to align IT strategy with business strategy in establishing and implementing effective IT governance. The purpose of this study is to find out the relationship between IT governance implementation factors and IS effectiveness, and the moderating effect of strategic alignment of IS strategy with business strategy on IS effectiveness. IT governance implementation factors consist of IT vendor management, IT human resource management, and IT infrastructure. Strategic alignment was measured as the alignment between business strategic orientation and IS strategic orientation that used in the research of Chan et al.(1997). In the relationship between three IT governance implementation factors and IS effectiveness, the results of multiple regression analyses showed that IT human resource management is an important determinant to influence IS effectiveness. The additional analysis using multiple regression showed that strategic alignment of IS strategy with business strategy has moderated the relationship between IT governance implementation factors and IS effectiveness.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.6
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• pp.98-111
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• 2009

The objective of this study is to revise the related regulations and laws of intelligent transport systems performance tests and methods. This study improves the reliability of present traffic information, reduce public discontent by systematic reforms and reduce national and social costs through the analysis of intelligent transport system performance tests'current status and problems. This study will maximize the investment profits and efficiency of ITS system as the reliability of transportation information which is created through the maintenance of ITS equipment and center, systemization of work responsibility through close analysis of ITS performance test and overall evaluation of role of ITS performance assessment organization will improve and new level of service will be born.

• The Journal of Information Systems
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• v.25 no.2
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• pp.111-129
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• 2016

Purpose Today, world-wide societies share their daily life and many communities exchange their information through the explosive developed SNS and the social media systems. However, many SNS fatigue related factors forced the discontinuance of SNS. This paper is aim to examine effect of SNS feature and negative emotion to figure out the reason of SNS discontinuance. This is verifying the effect of maintenance of SNS, security concern and psychological concern on SNS fatigue and the effect of upward/lateral comparison on negative emotion. Moreover, the effect of SNS fatigue and negative concern on the SNS discontinuance intention was examined. Design/methodology/approach This research used to the survey method to test its hypotheses and the survey population is Facebook SNS users. A software tool called AMOS 18 is used to analyze the structural equation model. Findings The results showed that maintenance of SNS, security concern and psychological concern had a positive effect on SNS fatigue respectively and upward/lateral comparison did on negative emotion. In addition, SNS fatigue and negative emotion had significant effect on discontinuance intention.