• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2012년도 춘계학술논문집 2부
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• pp.512-516
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• 2012

Recently the Korean government's green energy growth policy has been taken at the national level due to the sufficient supply of renewable energy. Some specific technique should be taken in consideration for the operation of the grid voltage and power quality management. In this case, there may have some chance of operational problems. Typical problems arise when grid-connected solar power produced by Pacific sunshine. The power flow in the reverse direction can create overvoltage on the distribution line and gives value of malfunction on the system. Line voltage and overvoltage adjustment practice can stop these symptoms occurred. Under these circumstances, this paper presents an interconnection test devices for photovoltaic(PV) systems composed of distribution system simulator, PV system simulator and control and monitoring systems using the LabVIEW S/W, and simulates the customer voltage characteristics considering the 3 parameters on the introduction capacity for PV systems, system configuration and Power factor. This paper also proposes a new calculation algorithm for voltage profile to make comparison between calculation values and test device values. The results show that the simulation results for the normal operation characteristics of PV systems which are very practical and effective.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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• pp.410-413
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• 2007

정보기술(IT)은 오늘날 조직의 경영 환경개선 및 혁신, 생산성 향상, 업무의 효율성과 효과성 제고 등에 있어서 절대적으로 필요한 도구가 됐으며 모든 분야에 있어서 널리 활용되고 있다. IT 특성이 변화주기가 빠르고 시장의 지배력과 연동됨에 따라 조직은 신기술 IT를 적용하여 시장에서 경쟁우위에 서고자 한다. 그러나 무계획적으로 무분별하게 시스템이 도입되어 조직내에서 정보화자산에 대한 관리가 부실화되고 있는 실정이며, 특히 PBS 제도하에 있는 공공기관에서의 정보화 자원관리는 단일성에 끝나는 경우가 많아 지속적인 관리가 현실적으로 어렵다. 이에 정부주도하에 정보시스템의 대규모화에 따른 상호운용성과 통합성 제고, 시스템에 대한 평가체계 및 지속적인 진화관리, 정보화 투자에 대한 효과 기대 등을 위해 도입하고 있는 ITA를 기반으로 기관에서의 정보화 자산 및 자원를 효과적으로 관리할 수 구축 방안을 제시하고자 한다.

• 산경연구논집
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• 제10권5호
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• pp.49-58
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• 2019

Purpose - Consumer behaviors or decision-making process has been changing recently as the consumer environment, including mobile everyday life, has changed. In view of this changing consumer smart environment, this study aims to investigate structural relation about the influence omni-channel propensity and regulatory focus on consideration set formation. Research design, data, and methodology - In order to proceed with this study, we review previous studies and setting hypotheses. The hypothesis was verified through a survey that was conducted for university students with experience in purchasing in less than three months. With reference to previous studies, operational definition was made for the questionnaire design. From 2018 Nov. to 2019 Feb. Survey was conducted on the panel consumers who purchase item within that period. 315 collected survey data were used to verify hypotheses except the data that had incorrect values. This data were used for SPSS/AMOS for confirm hypothesis which developed by researcher. Results - The results of this study are as follows. First, Consumers were considering a more heterogeneous alternatives if they were more omni-channel propensity in the process of forming consideration set. Second, Consumers were more conscious of the price if they were more omni-channel propensity Third, Consumers were considering a more newness alternatives if they were more omni-channel propensity in the process of forming consideration set. Meanwhile, The results of the study on regulatory focus and consideration set relationships are as follows. Consumers were considering a more heterogeneous alternatives if they were more promotion focus tendency in the process of forming consideration set. Second, Prevention focus tendency were more conscious of the price in the process of considering alternatives. Third, Consumers were considering a more newness alternatives if they were more promotion focus tendency. Conclusions - Depending on the changing consumer environment, the omni-channel propensity was shown to influence the formation of the consideration set. Also, Regulatory focus of consumers significantly influence to formation of consideration set. this study also contributes to the development of the theory as well as the practical approach with understanding consumer decision process on smart(mobile) environment.

• Environmental Analysis Health and Toxicology
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• 제21권2호
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• pp.197-208
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• 2006

The hazards of chemicals can be classified using classification criteria that are based on physical, chemical and ecotoxicological endpoints. These criteria may be developed be iteratively, based on scientific or regulatory processes. A number of national and international schemes have been developed over the past 50 years, and some, such as the UN Dangerous Goods system or the EC system for hazardous substances, are in widespread use. However, the unnecessarily complicated multiplicity of existing hazard classifications created much unnecessary confusion at the user level, and a recommendation was made at the 1992 Rio Earth summit to develop a globally harmonized chemical hazard classification and compatible labelling system, including material safety data sheets and easily understandable symbols, that could be used for manufacture, transport, use and disposal of chemical substances. This became the globally harmonized system for the Classification and Labelling of Chemicals (GHS). The developmental phase of the GHS is largely complete. Consistent criteria for categorizing chemicals according to their toxic, physical, chemical and ecological hazards are now available. Consistent hazard communication tools such as labelling and material safety data sheets are also close to finalizations. The next phase is implementation of the GHS. The Intergovernmental Forum for Chemical Safety recommends that all countries implement the GHS as soon as possible with a view to have the system fully operational by 2008. When the GHS is in place, the world will finally have one system for classification of chemical hazards.

• 한국국방경영분석학회지
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• 제37권1호
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• pp.119-128
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• 2011

이 연구는 무인항공기 체계운용 효과도를 고려한 임무분석연구를 다룬다. 이 임무분석절차는 (1) 기본 MANA 모델 시나리오 생성, (2) 실험계획에 의한 입력변수조합 설계, (3) 기본 MANA 모델 시나리오와 설계된 입력변수조합과의 연결, (4) Data Farming 및 일괄처리에 의한 모델 수행, (5) 모델 수행결과의 통계분석 등 5단계로 이루어진다. 임무분석결과로 독립변수의 종속변수(운용 효과도)에 영향을 마치는 정도는 식별거리, 탐지 폭, 비행고도, 비행속도, 센서 개구각, 식별확률 순으로 작아지고, 기준 시나리오를 개선된 시나리오로 변경하여 운용할 경우 운용효과가 10.2% 증가할 수 있음을 제시한다.

• 대한전자공학회논문지SD
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• 제45권9호
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• pp.103-109
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• 2008

본 논문은 H.264 디코더용 인트라 예측 회로 구조와 설계를 제시한다. H.264의 인트라 예측에는 총 17개의 예측 모드, 즉 루마 $4\times4$ 블록을 위한 9개의 예측 모드, 루마 $16\times16$ 블록을 위한 4개의 예측 모드, 크로마 $8\times8$ 블록을 위한 4개의 예측 모드가 있다 모든 예측 모드에서 공통된 연산들을 추출하여 이들을 수행하기 위한 공통연산부를 정의하였다. 모든 예측 모드에서 이 연산부를 공유하는 제안된 회로 구조는 설계 측면에서 체계적이고 회로 크기 측면에서 효율적이다.

• 한국환경보건학회지
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• 제31권1호
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• pp.15-22
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• 2005

This study was conducted to evaluate air injection mode on stabilization of solid waste in lysimeter. For three lysimeters, one was maintained under anaerobic condition as control, and air was injected into two lysimeters in continuous mode (atmospheric pressure) and intermittent mode (high pressure of 2 bar). Distilled water was sprayed over solid waste in 1.4 l/$m^3$(solid waste)/day, supposing rainfall intensity of 1,200 mm/yr and 30% infiltration. Oxygen in landfill gas was not detected in control lysimeter during operational days. After 30 day-aeration, oxygen concentrations of continuous and intermittent modes were maintained in 14% and 6%, respectively. $COD_{Cr}$ removal efficiencies of continuous and intermittent modes were about 70% and 50%, and BOD5 removal efficiencies were about 80% and 20%, respectively. In view of oxygen supply, and $COD_{Cr}$ and $BOD_5$ removal, continuous air injection mode of atmospheric pressure was more effective than intermittent mode of 2 bar. Settling degree of solid waste in case of two air injection modes was 3 times higher than that of anaerobic condition as control. Considering the above results, it was thought that air injection (especially continuous atmospheric pressure) could improve degradation of solid waste and induce preliminary stabilization in landfill site.

• Journal of Information Technology Applications and Management
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• 제16권4호
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• pp.205-222
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• 2009

Considering time-lag in the performance evaluation of information system (IS) investment is important because its effect reveals after certain period of time passed. Particularly it is more in the systems of e-government informatization projects which the amount of investment and the scale of business are huge. Many methods to solve this issue have been proposed such as system dynamics methods, simulations, structural equations etc. However, it is still difficult and unsolved problem because collecting practical data for time-lag analysis is very hard. In this paper, we analyze IS time-lag effect through factor analysis using the accumulated practical operational DB data. For the performance evaluation of the G4C system, the representative e-government web portal, we selected eleven factors reflecting time passing in G4C DB data. With these factors this paper conduct time-lag analysis in four view points. First, we conducted 'Stabilizing of G4C system' and got a result that IS is needed about three years for the stabilization. Second, we conducted 'Utilization of G4C system' and got a result that the utilization reaches appropriate level after in three years later after the introduction of G4C system. Third, we conducted 'Cost reduction effect' and got a result that cost reduction is stable in the third year after the introduction of G4C system. Lastly, we conducted 'System maturity effect' and got a result that the system reaches to the quality level that users expect after third to fourth years. According to the results of this research, we found that performance of IS improv continuously not immediately, and it needs three or four years of time-lag.

• 천문학회보
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• 제42권2호
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• pp.58.1-58.1
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• 2017

The NISS (Near-infrared Imaging Spectrometer for Star formation history) is the near-infrared spectro-photometric instrument optimized to the first Next Generation of small satellite (NEXTSat-1). The off-axis optics was developed to cover a wide field of view with 2 deg. ${\times}$ 2 deg. as well as a wide wavelength range from 0.95 to $2.5{\mu}m$. Considering the simple alignment scheme, afocal system was adapted in the optical components. The mechanical structures were tested under the space environment. We have obtained the accurate calibration data using our test facilities under the operational condition. After the final integration of flight model into the satellite, the communication with the satellite and the functional test were passed. The NISS will be launched in early 2018. During around 2-year operation, the spectro-photometric survey covering more than 100 square degree will be performed. To achieve the major scientific objectives for the study of the cosmic star formation in local and distant universe, the main observational targets will be nearby galaxies, galaxy clusters, star-forming regions and low background regions. Here, we report the final performance of the flight model of the NISS.

• 한국수학교육학회지시리즈A:수학교육
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• 제56권1호
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• pp.101-118
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• 2017

In this article we study a reconstruction of mathematical knowledge on trigonometry by the method of ascent from the abstract to the concrete from the pedagogical viewpoint of dialectic. The direction of education is shifting in a way that emphasizes the active constitution of knowledge by the learning subjects from the perspective that knowledge is transferred from the teacher to the student. In mathematics education, active discussions on the construction of mathematical knowledge by learners have been going on since the late 1990s. In Korea, concepts and aspects of constructivism such as operational constructivism, radical constructivism, and social constructivism were introduced. However, examples of practical construction according to the direction of construction of mathematical knowledge are very hard to find. In this study, we discuss the direction of the actual construction of mathematical knowledge and suggest a concrete example of the actual construction of trigonometry knowledge from a constructivist point of view. In particular, we discuss the process of the construction of theoretical knowledge, the ascent from the abstract to the concrete, based on the literature study from the pedagogical viewpoint of dialectic, and show how to construct the mathematical knowledge on trigonometry by the method of ascent from the abstract to the concrete. Through this study, it is expected to introduce the new direction and new method of knowledge construction as 'the ascent from the abstract to the concrete', and to present the possibility of applying dialectic concepts to mathematics education.