• 조명전기설비학회논문지
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• 제27권10호
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• pp.1-8
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• 2013

Wireless Visible Light Communication is the technology that enables communication using LED illumination Infrastructure instead of existing illumination such as incandescent lamp or fluorescent light. Because VLC uses light for communication, it has no problem of frequency permission and is harmless to human body. It is also possible to check the communication through eye. So VLC can be used as a supplement to the Radio Frequency communication, Infrared in indoor environment. So far, researchers on the LED Visible light communication have focused on the increasing transmission speed, transmission distance, modulation method. However, there is few research of main factors that influence on system performance. System performance has been mainly predicted through simulation. In this paper, I recognized that these factors such as outside light noise, obstacle, LED panel position or emitted angle have a great impact on wireless communication system. So I experimented VLC system by changing distance and position to discover location suitable for BER regulation.

• 한국태양에너지학회 논문집
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• 제27권2호
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• pp.87-93
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• 2007

The demand for solar electric power systems, namely, photovoltaic system has grown steadily in our country over the last 10 years. However, the main obstacle against using photovoltaic system is the financial viability especially concerned with initial cost. The other factors affecting the economic viability of photovoltaic system are cost of electric energy, amount of electric energy produced by the photovoltaic system, discount rate, energy cost escalation rate, inflation rate, project life, and so on. Therefore, this thesis studies on the effect of various relating factors on economic evaluation of photovoltaic system in residential building by calculating payback period.

• 한국경영공학회지
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• 제23권4호
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• pp.19-31
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• 2018

Corruption is a serious political factor that distorts economic structure and slows economic development. In particular, the transition to the market opening economy increases the corruption incentives due to the transitional situation. The purpose of this study is to investigate the influencing factors on corruption using 2013 Myanmar Enterprise Survey data provided by World Bank. As a result of the analysis, it was found that the manager's willingness to dealing the regulation and the necessity of licensing had a positive relationship with corruption at the level of 90% and 95%, respectively. In the competitive environment factor, the intensity of the competition showed a significant increase at the level of 90%. In the institutional environment, the perception of social corruption and the obstacle of the taxation authorities increased the corruption. On the other hand, the increase in the instability of the political environment and strict enforcement of laws has been shown to reduce corruption. However, there was no significant relationship between managerial capacity, corruption of competitors, tax rate, and administrative environment.

• 한국군사과학기술학회지
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• 제16권2호
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• pp.118-129
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• 2013

Since the obstacles and mines are of the risk factors for operating ships and submarines, the active sonar system is inevitably used to avoid the hazards in ocean environment. In this paper, modeling and simulation algorithm is used for active sonar systemto quantify the measure of mission achievability, which is known as Measure of Effectiveness(MOE), specifically for detection in this study. MOE for detection is directly formulated as a Cumulative Detection Probability(CDP) calculated from Probability of Detection(PD) in range and azimuth. The detection probability is calculated from Transmission Loss(TL) and the sonar parameters such asDirectivity Index (DI) calculated from the shape of transmitted and received array, steered beam patterns, and Reverberation Level (RL). The developed code is applied to demonstrating its applicability.

• 한국실내디자인학회논문집
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• 제38호
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• pp.192-200
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• 2003

Interactions with the environment do to firm, deny, or challenge the existing knowledge. People who suffer from the loss of the sight have difficulty conceiving the space and the direction as well as walking. In the study, it wanted to reveal that the border that Is provided as a transfer clue has psychological and functional meaning to the sight-disabled people under given circumstances. It suggests that there is another space among the physical borders and analyzes the utilization clue in the entry space, which is the first starting point that can transfer, and obstacle factors which may happen at that point. And, it also wanted to present the surrounding environmental improvement ways for walking which is smooth and confident based on them.

• 한국정밀공학회지
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• 제20권11호
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• pp.79-90
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• 2003

In this paper, we propose a multisensor-based navigation algorithm for a mobile robot, which is intelligently searching the goal location in unknown dynamic environments using multi-ultrasonic sensor. Instead of using “sensor fusion” method which generates the trajectory of a robot based upon the environment model and sensory data, “command fusion” method by fuzzy inference is used to govern the robot motions. The major factors for robot navigation are represented as a cost function. Using the data of the robot states and the environment, the weight value of each factor using fuzzy inference is determined for an optimal trajectory in dynamic environments. For the evaluation of the proposed algorithm, we performed simulations in PC as well as experiments with IRL-2002. The results show that the proposed algorithm is apt to identify obstacles in unknown environments to guide the robot to the goal location safely.

• 한국산업융합학회 논문집
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• 제21권3호
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• pp.125-131
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• 2018

In this paper, we propose a homogeneous multisensor-based navigation algorithm for a mobile robot, which is intelligently searching the goal location in unknown dynamic environments with moving obstacles using multi-ultrasonic sensor. Instead of using "sensor fusion" method which generates the trajectory of a robot based upon the environment model and sensory data, "command fusion" method by fuzzy inference is used to govern the robot motions. The major factors for robot navigation are represented as a cost function. Using the data of the robot states and the environment, the weight value of each factor using fuzzy inference is determined for an optimal trajectory in dynamic environments. For the evaluation of the proposed algorithm, we performed simulations in PC as well as real experiments with mobile robot, AmigoBot. The results show that the proposed algorithm is apt to identify obstacles in unknown environments to guide the robot to the goal location safely.

• Architectural research
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• 제2권1호
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• pp.27-34
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• 2000

Most research on high-rise housing has focused on low-income residences, and usually the psychological and social well-being of women and children. The validity of such findings are questionable for other populations since high-rise living has served other groups and their various needs in particular settings. Lack of knowledge and understanding about high-rises has represented an obstacle to the accurate representation of American urban reality in residential environments. The review of literature and factor analysis identified Important environmental factors. The survey was conducted in the selected downtown high-rise communities of major U.S. cities. Analyses revealed that there were unique characteristics of residents who prefer to live in this type of housing. It was also found that living in middle-income urban high-rise condominiums does not contribute significantly to the problems associated with high-rise living itself. Even though there were some deficiencies of social interaction and activities among residents, the middle-income condominiums were serving particular residents as maintenance-free and safe place imprinted by a positive image of sweet memories or sometimes by a window view presiding over downtown skyline.

• International Commerce and Information Review
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• 제2권1호
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• pp.69-81
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• 2009

In the past, trades with the Latin American markets were not active since the South Korean companies simply considered them substitute markets whenever exports were slow. However, the importance of these markets is highlighted anew thanks to the signing of the Korea-Chile Free Trade Agreement (FTA). Presently, Latin American nations are pursuing FTA with various nations in the world, regardless of the geographic boundaries, in order to vitalize their economy and attract foreign capital. Despite these efforts to liberalize the market, Latin American regions continue to restrict importation by leveraging diverse set of trade regulation policies. This research examines trade regulation policies in the Latin American regions and proposes Korea's countermeasures.

• 한국과학교육학회지
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• 제21권5호
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• pp.773-794
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• 2001

Many studies on the professional development of science teachers demonstrated that induction teachers' conceptions of teaching science are important factors in developing their professionalism. The present study was conducted to describe in detail the progress of two science induction teachers, June and Mike, towards conceptual change teaching, and to investigate secondary induction science teachers' conceptions of teaching science by analysing their conceptual ecologies. The study was interpretive, using multiple data sources to achieve a triangulation of data. Both June and Mike held strongly positive learning in their views of knowledge and science. Holding positivist views of knowledge and of science is likely to be a major obstacle for anyone coming to understand constructivism and its implications in teaching for conceptual change. This argument resonates in several key ways with the teachers' cases, even though I recognize differences between scenario and teachers, and between teachers themselves.