• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.33-38
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• 2003

There have been continuous efforts for developing the automatic mechanical design system to increase the efficiency of the tedious design process. However, these efforts have been concentrated on single platform application. Hence, the developed systems have been available only in a designated place and time and have been difficult to modify. It is proposed in this study that a web-based design system is developed to offer more reliability and convenience without any restriction of tine and place. The developed system is programed based on Java, and architecture of the system has object-oriented features of Servlet and JSP and is independent on any operating systems. The developed system has been applied to the initial design of multi-stage gear dirves but however as the framework of the developed system is quite versatile, its application to automatic design of any mechanical system or evaluation can be easily expected.

• 한국공작기계학회논문집
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• 제13권2호
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• pp.54-60
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• 2004

There have been continuous efforts for developing the automatic mechanical design system to increase the efficiency of the tedious design process. However, these efforts have been concentrated on single platform application. Hence, the developed systems have been available only in a designated place and time and have been difficult to modify. In this study a web-based design system is developed to offer more reliability and convenience without my restriction of time and place. The developed system is programmed based on Java, and the architecture of the system has object-oriented features of Servlet and JSP and is independent on my operating systems. The developed system has been applied to the initial design of multi-stage gear drives, but as the framework of the developed system is however quite versatile, its application to automatic design of my mechanical system or evaluation can be easily expected.

• 한국군사과학기술학회지
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• 제18권3호
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• pp.267-274
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• 2015

It is necessary to both analyze root-cause of non-conformance of effective illumination time to the specification, and estimate the storage lifetime for 81 mm illuminating projectile stockpiled over 10 years. In this paper, aging mechanism of magnesium flare material due to long-term storage was supposed, and two-stage tests, pre-test and main test based on accelerated degradation tests were performed. Field storage environment of moistureproof was set up, and illumination times in the accelerated degradation tests for temperatures 60 and $70^{\circ}C$ were measured. Then, storage reliability of the projectile was estimated through analyzing the measured data and applying distribution-based degradation models to the data. The $B_{10}$ life by which 10 % of a population of the projectiles will have failed at storage temperature of $25^{\circ}C$ was estimated about 7 years.

• The Journal of Asian Finance, Economics and Business
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• 제8권7호
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• pp.79-90
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• 2021

The purpose of this research is to identify factors affecting the acceptance and use of e-tax services among medium taxpayers in Phnom Penh, Cambodia. The researcher conducted the study based on a quantitative approach by using multi-stage sampling method, which selects a sample size by two or more stages. The first stage sampling was the stratified random sampling and the subsequent stage was purposive sampling. In this study, the stratified random sampling was first used, followed by purposive sampling. The data were collected from 450 medium taxpayers who experienced using e-tax services located in three tax branches in Phnom Penh. This study adapted the confirmatory factor analysis (CFA) and structural equation model (SEM) to analyze the model accuracy, reliability and influence of various variables. The primary result showed that behavioral intention has a significant effect on user behavior of e-tax services among medium taxpayers in Phnom Penh, Cambodia. Moreover, the results revealed that performance expectancy, effort expectancy, social influence, and anxiety have significant impact on behavioral intention. In addition, social influence has the strongest impact on behavioral intention, followed by anxiety, performance expectancy and effort expectancy. Conversely, facilitating conditions, trust in government, and trust in internet do not influence behavioral intention.

• 신재생에너지
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• 제10권3호
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• pp.47-54
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• 2014

Recently, BESS is considered as one of essential countermeasure for demand side management. However, an economic evaluation is critical issue for the introduction of power system because the cost of BESS is very high in present stage. Therefor, this paper presents economic evaluation method for customer use case by considering peak shaving function based on the real time price. From the case study on the model power system and educational customer, it is confirmed that the proposed method is a practical tool for the economic analysis of BESS. and analytical approach for the reliability assessment in radially operated distribution systems. The approach can estimate the expected reliability performance of distribution systems by a direct assessment of the configuration of the systems using the reliability indexes such as NDP (Non-Delivery Power) and NDE (Non-Delivery Energy). The indexes can only consider the number and configuration of the load, but can not consider the characteristics of the load which is the one of the most important factor in the investment cost for the distribution systems. Therefore, this paper presents the new performance indexes for the investment of the distribution facilities considering both the expected interruption cost for the load section and the operation characteristics of Energy Storage System. The results from a case study show that the proposed methods can be a practical tool for the reliability management in distribution systems including Energy Storage System.

• Smart Structures and Systems
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• 제18권6호
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• pp.1145-1167
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• 2016

This study presents a new method to computes analytical fragility curves of a structure subject to tsunami waves. The method uses dynamic analysis at each stage of the computation. First, the smooth particle hydrodynamics (SPH) model simulates the propagation of the tsunami waves from shallow water to their impact on the target structure. The advantage of SPH over mesh based methods is its capability to model wave surface interaction when large deformations are involved, such as the impact of water on a structure. Although SPH is computationally more expensive than mesh based method, nowadays the advent of parallel computing on general purpose graphic processing unit overcome this limitation. Then, the impact force is applied to a finite element model of the structure and its dynamic non-linear response is computed. When a data-set of tsunami waves is used analytical fragility curves can be computed. This study proves it is possible to obtain the response of a structure to a tsunami wave using state of the art dynamic models in every stage of the computation at an affordable cost.

• 한국CDE학회논문집
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• 제21권2호
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• pp.130-142
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• 2016

BIM library, as a systematic collection of BIM objects where the building information is stored, is a vital factor to construct the BIM based work environment. However, construction business is faced the problems relating BIM library such as the absence of the standard for establishing BIM library, the discontinuity of BIM library's compatibility and the lack of practice applicable BIM library. These problems cause the decreasing work efficiency and the recreating BIM model, by delivering inefficient information required in each stage and application field. The purpose of this study is to suggest the integrated management system for property information of BIM library in order to minimize the reworking and to manage information of each stage and application field when exchanging and sharing information. To achieve this, the BIM information classification, the criteria of property requirements for information exchange in BIM application field and the BIM library management system are developed. This study could contributes to ensuring the reliability and accuracy of results of BIM based analysis and to enhancing the speed of business process with sharing and exchanging building information utilizing a single BIM model.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권3호
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• pp.757-770
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• 2022

Palmprint recognition has drawn increasingly attentions in the past decade due to its uniqueness and reliability. Traditional palmprint recognition methods usually use high-resolution images as the identification basis so that they can achieve relatively high precision. However, high-resolution images mean more computation cost in the recognition process, which usually cannot be guaranteed in mobile computing. Therefore, this paper proposes an improved low-resolution palmprint image recognition method based on residual networks. The main contributions include: 1) We introduce a channel attention mechanism to refactor the extracted feature maps, which can pay more attention to the informative feature maps and suppress the useless ones. 2) The ResStage group structure proposed by us divides the original residual block into three stages, and we stabilize the signal characteristics before each stage by means of BN normalization operation to enhance the feature channel. Comparison experiments are conducted on a public dataset provided by the Hong Kong Polytechnic University. Experimental results show that the proposed method achieve a rank-1 accuracy of 98.17% when tested on low-resolution images with the size of 12dpi, which outperforms all the compared methods obviously.

• 대한산업공학회지
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• 제21권1호
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• pp.17-32
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• 1995

The objective of this study is to develop a general design and performance evaluation model for the system designers in the initial design phase of the integrated automatic manufacturing system based on the RAM(Reliability, Availability and Maintainability) and life cycle cost(LCC). The methodology proposed in this research includes the following two stages. First, a deterministic approach to the solution of optimal work station arrangement for the initial system configuration is considered under the assumption that the system availability is one(no failure and maintenance), and then a stochastic simulation model based on RAM and LCC is developed. Using the results of these two stage simulation, a system performance index(SPI) was developed for the performance evaluation of the proposed system. Also a computer program is developed.

• 한국인터넷방송통신학회논문지
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• 제22권5호
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• pp.147-157
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• 2022

본 연구의 목적은 영향평가에 대한 정의부터 국내외 인공지능 서비스 영향평가 사례에 대한 분석을 바탕으로 인공지능 서비스 영향평가 추진에 대한 정책적 제언을 수립하는 것이다. 이를 위해서 국내외 타 분야에서 추진된 영향평가 사례, 인공지능 서비스 국내외 영향평가 사례를 바탕으로 추진 방향을 분석하였다. 국내 인공지능 서비스 영향평가는 다소 광범위하고 포괄적이며, 시점도 사전적 예방 수단에 그치지 않고 상시적·사후적 위험성 관리를 예정하고 있다. 단계별 추진 방안으로 1단계에는 AI 수준 조사 기반의 경제적 효과 등의 정량적 지표를 개발한 후, 2단계에서는 지능정보화 기본법에 기술된 안전성 및 신뢰성, 인공지능 윤리 등 정보문화, 고용·노동 등 사회·경제, 정보보호, 국민의 일상생활에 미치는 영향에 미치는 분야별 평가체계를 마련한다. 3단계에서는 세부 측정지표나 방식 등의 논의를 확대하고 영향평가 결과가 인공지능 정책에 반영하는 환류 체계 포함된다면 국내의 인공지능 경쟁력 강화에 도움이 되는 정책 수단이 될 수 있다는 것을 제시하였다. 본 연구는 향후 정책 설계자, 인공지능 서비스 개발자, 시민단체 등 다양한 참여자를 통한 분석이 요구된다.