• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.496-505
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• 2016

The purpose of this study was to investigate the economic effects of a flame retardant aluminum screen developed by a company Economic effects were analyzed in terms of micro and macro-economic aspects. In the macro-economic aspect, economic effects were analyzed under the assumptions that the total import volume of flame retardant aluminum screen was approximately $50m^2$ in 2015 and that possible import substitution rates were 100%, 80%, and 60%. Results showed economic values of 2.25 billion won (100% import substitution rates), 1.8 billion won (80% import substitution rates), and 1.35 billion won (60% import substitution rates). If existing farms which had been using imported flame retardant aluminum screen replaced it newly developed with the flame-retardant aluminum screen developed in this study at rates of 100%, 80%, and 60%, the farms could save 750 million won, 60 million won, and 45 million won, respectively. Furthermore, the social cost savings from fire prevention could be 1.184 billion won. In the micro-economic aspect, if a farm with a typical-size ($1,000m^2$) greenhouse growing red pepper wanted to install flame retardant aluminum screen instead of generic aluminum screen, the farm may only pay an additional cost of 720,000 won. In comparison, if the farm chose fire insurance instead of flame-retardant aluminum screen, then the farm would pay 21,000,000 won for fire insurance. The above results show that the economic effect of flame retardant aluminum screen developed by the company would be be very efficient compared to the imported one.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.6
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• pp.589-596
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• 2014

Joints, fasteners or connected parts frequently have a significant effect on the dynamical behavior of assembled mechanical structures. Therefore, the analytical prediction of structural responses depends on the accuracy of joint modeling. This paper deals with the formulation and analysis of dynamic mechanism for joint flexibilities whose relevant magnitudes of stiffnesses are investigated by using linear and torsional springs. The equation of motion is derived by using a generic joint in the middle of clamped-clamped beam. A reanalysis due to changes in magnitudes of joint stiffnesses is based on the reduced analysis where the binomial series terms are used as basis vectors. The solution procedures are straightforward and the method can be readily used with a general finite element method. The computational effort needed by this approach is usually much smaller than the effort needed for complete vibration analysis. Two numerical examples show that accurate results are obtained efficiently by reducing the number of degree in the reduced model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.3A
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• pp.240-248
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• 2006

In this paper, we consider an OFDM receiver algorithm design for IEEE 802.11a/p system, which targeting large coverage area while keeping the transmission format unchanged. Particularly, taking into account the inter-symbol interference(ISI) and inter-carrier interference(ICI) that can be induced with large RMS delay spread, we employ channel shortening time-domain equalizer(TEQ) and evaluate the receiver performance in terms of SINR and packet error rate(PER). The preamble defined in IEEE802.11a/p is used to estimated the initial equalizer tap coefficients. Primary purpose of the paper is to give an answer to the question, though partially, whether or not 16-QAM constellation can be used in none line of sight environment at the boundary of a large coverage area. To this end, we first analyze the required TEQ parameters for the target channel environment and then perform simulation for PER performance evaluation in a generic frequency selective fading channel with exponential power-delay profile.

• Industrial Engineering and Management Systems
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• v.11 no.3
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• pp.233-240
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• 2012

The implementation of business process management (BPM) systems in large number of business organizations transforms BPM system into such a level of maturity and tends to collect large repositories of business process (BP) models. This issue encourages BP flexibility that leads to a large number of process variants derived from the same model, but differing in structure, to be stored in the large repositories of BP models. Therefore, the repositories may include thousands of activities and related business objects with variation of requirements and quality of service. It is a common practice to customize processes from reference processes or templates in order to reduce the time and effort required to design and deploy processes on all levels. In order to address redundancy and underutilization problems, a generic process model, called as reference BP, is absolutely necessary to cover the best of process variants. This study aims to develop multiple-objective business process genetic algorithm (MOBPGA) to find a set of non-dominated (Pareto) solutions of business reference model to enhance conventional approach which considered only a single objective on creating BP reference model by using proximity score measurement. A mixed-integer linear program is constructed to evaluate performance of the proposed MOBPGA on small-scale problems by using standard measures for multiple-objective techniques. The results will show the viability of applying MOBPGA in terms of simultaneously maximizing proximity score measurement, minimizing total duration, and total costs of the selected reference model.

• Journal of KIISE
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• v.42 no.1
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• pp.107-113
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• 2015

In a database system, updates on pages that are made by a transaction should be stored in a secondary storage before the commit is complete. Generic secondary storages have volatile DRAM caches to hide long latency for non-volatile media. However, as logs that are only written to the volatile DRAM cache don't ensure durability, logging latency cannot be hidden. Recently, a flash SSD with capacitor-backed DRAM cache was developed to overcome the shortcoming. Storage devices, like those with a non-volatile cache, will increase transaction throughput because transactions can commit as soon as the logs reach the cache. In this paper, we analyzed performance in terms of transaction throughput when the SSD with capacitor-backed DRAM cache was used as log storage. The transaction throughput can be improved over three times, by committing right after storing the logs to the DRAM cache, rather than to a secondary storage device. Also, we showed that it could acquire over 73% of the ideal logging performance with proper tuning.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.2
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• pp.1-7
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• 2018

Suspension bridge cables made of high strength steel wires require periodical maintenance in accordance with the axial force of cable-band bolts, since the bolts in suspension bridges can undergo tension decrease due to creep of cable wires, bolt relaxation, load fluctuation, and cable re-arrangement, etc. Consequently, this study is aimed at investigating and subsequently evaluating the critical factors with respect to the bolt tension-decrease phenomenon in SR suspension bridge in Korea, based on field monitoring, theoretical studies, and field record management works. From the observation, it is interesting to note that the decrease in the bolt tension force is typically accompanied by plastic deformation of the zinc plating layers in the cable wires. In addition, a framework corresponding to generic methodologies to characterize the deformation in terms of the bolt tension-decrease and long-term history management has been developed in this exploratory study.

• The Journal of Korean Society for School & Community Health Education
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• v.17 no.2
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• pp.1-16
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• 2016

Objectives: The objective of this study is to evaluate the correlates of depression and perception gap of adolescents' Health-Related Quality of Life (HRQOL) between Parents and Children. Methods: Research targets are all students and their parents who are enrolled in from 1st~3rd grade of middle school to $1^{st}$ grade of high school which was selected intentionally. The survey was conducted from May $16^{th}$ to June $9^{th}$ in 2014 by research staffs equipped with structured questionnaire. $PedsQL^{TM}4.0$ Generic Core Scales and Korean form of the Kovacs' Children's Depression Inventory were the main tool for measuring the HRQOL and depression. Data of 985 respondents, both of parents and children, was used for analysis of this study. Results: In terms of gender difference of depression, 5.8% of adolescents, 3.2% of male and 8.5% of female (p<0.001), are shown depression symptom. Depression rate of the low level students of academic achievement was 11.0% which is the lowest rate to compare to 4.3% of middle level and 2.6% of high level students (p<0.001). The case that parents overestimated their children's overall HRQOL is 3.699 times more likely to have depression symptom than the case which is in concurrence between parents and children. Especially the overestimation in social, emotional, and academic area of HRQOL promote depression 3.918 times, 3.371 times, and 2.258 times more than the agreement occurred of each areas. In contrast underestimation in physical area of HRQOL reduce depression 0.266 times less than the agreement occurred of the area. Conclusion: The perception gap of adolescents' HRQOL between parents and children is the most influential factor to adolescents' depression among all variables which was evaluated in this study.

• Safety and Health at Work
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• v.1 no.1
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• pp.29-36
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• 2010

This article describes a systematic roadmap master plan for advanced industrial safety and health policy in Korea, with an emphasis on. Since Korean industries had first emergence of industrial safety and health policy in 1953, enormous efforts have been made on upgrading the relevant laws in order to reflect real situation of industrial work environment in accordance with rapid changes of Korean and global business over three decades. Nevertheless, current policy has major defects; too much techniques-based articles, diverged contents in less organization, combined enforcement and punishments and finally enforcing regulations full of commands and control. These deficiencies have make it difficult to accommodate changes of social, industrial and employment environment in customized fashion. The approach to the solution must be generic at the level of paradigm-shift rather than local modifications and enhancement. The basic idea is to establish a new system integrated with a risk assessment scheme, which encourages employers to apply to their work environment under comprehensive responsibility. The risk assessment scheme is designed to enable to inspect employers' compliances afterwards. A project comprises four yearly phases based on applying zones; initially designating and operating a specified risk zone, gradually expanding the special zones during a period of 3 years (2010-2012) and the final zone expanded to entire nation. In each phase, the intermediate version of the system is updated through a process of precise and unbiased validation in terms of its operability, feasibility and sustainability with building relevant infrastructures as needed.

• The Korean Journal of Archival Studies
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• no.47
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• pp.255-286
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• 2016

This study aims to propose a tool for a comparison of public electronic records management in a public institution and a private records management facility and to reveal the considerations prior to decisions on the way of management. For developing a tool, it chooses CoMMPER as a basic model and modifies it after reviewing existing cost models, because only CoMMPER can over public records management. Modified-CoMMPER is added a new cost area[Aquisition], and is modified and extended cost elements and generic cost factors for the comparison. Public institutions which consider whether commission the management of public electronic records can use Modified-CoMMPER for comparing economic impacts in terms of long-term preservation. To make a rational decision on the way of management based on the economic analysis, this study proposed 3 main task. Fist, the scope of the activities has to be defined, second, the cost-effectiveness has to be estimated base on the cost model, for example Modified-CoMMPER, third, policy-making for the management of public electronic records must be proceeded based on the various researches on the cost of records management.

• (The)Study of the Eastern Classic
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• no.36
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• pp.85-104
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• 2009

This study examines a study of communication factor in Lunyu, as a communication text, in terms of communicator, audience, message, communication factor, communication text, interdisciplinary research. In many respects, it is generally accepted that Lunyu have been the generic references of the Oriental culture. Lunyu consider ethics, logic, and practicability as the qualifying requirement of communicator, asserting that communicator should speak true language, like a "chuntzu"(君子) does, and should also put their language into practice. The audience's attitude and method as contained in Lunyu are that hearers should have sharp ears for language, hear selectively the right language, and use the language suitable to the situation. It is also emphasized that the Hearer should actively lead in the situation of transactional communications. In Lunyu, one property of message is that language, which determines the rise and fall of a nation and is also the basis of judgement for other people, should comply with ethics and reasons and sould also be put into practice. In other words, credible message, as the practice of language, is the practical requirement of ethics and the qualification of a "chuntzu"(君子, superior man) in ruling the nation or conducting one's life.