• Journal of the Korean Institute of Gas
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• v.3 no.2 s.7
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• pp.24-33
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• 1999

The minimum safe separation distances from LPG filling station was discussed in this work based on the accident data from 1987 to 1998 in south korea, the initial damage of accident, and standards of countries. The safety distances are adequate to reduce ignition probability by released gas and provide space for implementation of emergency response after ignition. Therefore, the distances are related to the distance to LFL(Lower Flammable Limit) and the length of jet fire to prevent accident escalation. The range of the distance was suggested in this work to make standard with considering economic, culture, and safe guards.

• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.30-36
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• 2013

Recently the globalization of the media content industry, various activities have been made in the field of art and the speaker system is very important in the sound industry which is one of the arts. The directional characteristics of a loudspeaker refer to the radiation of sound in certain directions and are among the most important features of a loudspeaker. Designing a loudspeaker that can keep all of its constant directivity at all frequencies is difficult due to the wavelengths of audio frequencies and the size of horns and transducers. This study proposed gradient array methods to improve low frequency pattern control of full-range speakers to maximize Direct to Reverberant Ratios at the listeners.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.10
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• pp.9-16
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• 2004

The state assignment for a finite state machine greatly affects the delay, area, power dissipation, and testabilities of the sequential circuits. In order to improve the testabilities and power consumption, a new state assignment technique based on m-block partition is introduced in this paper. The algorithm minimizes the dependencies between groups of state variables are minimized and reduces switching activity by grouping the states depending on the state transition probability. In the sequel the length and number of feedback cycles are reduced with minimal switching activity on the state variables. Experiment shows significant improvement in testabilities and Power dissipation for benchmark circuits.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.07a
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• pp.237-238
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• 2019

현시대에 자율주행 기술이 자동차를 단순 이동수단에서 이동성을 확보한 생활공간으로 자동차의 근본적인 개념을 변화시켜 새로운 산업 패러다임적 가치뿐 아니라, 사회 경제적 변혁을 예고하고 있다. 이미 전 세계적인 기업들은 자율주행 시스템을 구축하고 개발하여 실제 생활에서 활용도 하고 있다. 그럼에도 불구하고 상용화를 하기 위해선 아직 법/제도의 부재, 안정성, 가격 등 여러부분에서 문제점들을 극복해야한다. 본 과제인 라인트레이서와 GPS를 활용한 자율주행시스템이 목적지를 지정하면 자율적으로 길이나 도로를 따라 이동하면서 장애물을 피해가게 만들어 안정성을 확보하고 이동하는 시간에 개인 여가 시간이나 생산적인 활동을 할수 있게 만들어 삶의 질 개선에 기여할 것이다. 이러한 기술들을 적극 활용하여 목적지를 설정하면 자율주행 하는 자동차로 설정하였고, 장애물 감지와 현재 방향 감지를 추가하였다. 장애물 감지와 방향 그리고 위치를 수신받기 위해 5개의 센서를 활용하였고 한번에 구동을 시키기 위해 센서 쉴드를 활용하여 기능을 확장 시켰다.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.293-298
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• 2008

This study was surveyed the effects by pollinating activity of Apis mellifera and Bombus terrestris released in the paprika vinyl-houses. The foraging activity and behaviour of A. mellifera and B. terrestris visited on the paprika flowers were nearly alike. The pick times of pollinating activity by A. mellifera and B. terrestris were showed the hightest at 11:00 and 15:00, and 09:00 to 11:00, respectively. The rate of fruit set by A. mellifera and B. terrestris released for pollinating paprika were same level with 94%, and these rate were higher than the fruit setting rate which was 92% by fan operated. The qualities of paprika produced by pollinators released were higher than those by fan operated. And weight per fruit, number of seeds per fruit and economical profit per 2,310 $m^2$ were over 10% higher than those by fan operated. Therefore the economical effects by the pollinating activities of A. mellifera and B. terrestris released in the paprika vinyl-houses were obviously demonstrated.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.381-391
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• 2018

This study was carried out to determine whether cage traps can be used to capture wild boars successfully, and to assess their response to different bait materials and the number of wild boars caught. Steel cage-traps ($4.0m{\times}1.5m{\times}1.2m$, $L{\times}W{\times}H$) were installed at two sites in Damyang County and at one site in Sunchang County, South Korea. To identify preferred bait-diet, baits were prepared with dry corn and fermented sour corn and placed in equal amounts at the sites close to wild boar pads at 200 m intervals. Before selecting trap locations where sufficient activity was observed, pre-baiting was undertaken and steel-framed traps were installed with gates open. Preference for bait materials was not clearly defined. After providing the bait for the first time, the number of days until wild boars ate all the food were counted. In the Damyang and Youngam areas, where hunting was allowed, total bait consumption took 6 to 12 days; in contrast, in the Sunchang area, where no hunting took place, total food consumption took only 5 days. In addition, after pre-baiting with the mixture of dry and sour corn for diet for about 8.7 days and then opening the trap gates for 3 more days, 13.7 days were necessary to catch 4.3 wild boars per trap. These results suggest that hunting intensity around trapping places was an important factor in determining the success of the traps.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.6
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• pp.634-643
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• 2020

Because of the continuous increase in the demand for and importance of marine space, marine exploration and survey activities are being actively conducted in Korea actively. Because the marine survey vessels used for these activities have special operational patterns depending on the purpose and probe vessels, research on maritime traffic risk is required. In this study, an attempt was made to determine the correlation of each factor with the effect of marine exploration and survey vessel operation on maritime traffic. The status of ocean exploration and survey vessels in operation in Korea was identified, as well as the special operational conditions of some of the ocean physical probes. Generally, the number of exploration and survey vessels involved per hour, total vessel length(including exploration equipment), operation, interval distance of exploration as per plan, and marine traffic conditions(traffic volume and speed) can be classified as operating factors. To compare the results of the environmental stress, a maritime traffic flow simulation based on the "ES" Model was performed with each of the identified operating factors as independent variables. The results of the analysis confirmed that the environmental stress significantly changed in the order of traffic volume, ship length and speed. In addition, it was confirmed that the environmental stress is reduced when the operation course is set at an angle with the nearby maritime traffic flow. Accordingly, it can help reduce the operator's burden if the survey vessel operator understands nearby maritime traffic conditions and reflects them in the operation method when setting the operation plan.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.1
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• pp.111-118
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• 2015

Students have chosen the various behaviors to prepare for the future during the university life. In general to be employed by someone and to create one's own business is likely to be regarded as difference ways. The objectives of this study is to find that whether student's planned behaviors such as albeit, internship, getting some certification are to be related with entrepreneurial intention, and entrepreneurial intention has positive relation with entrepreneurial decision makings based on theory of Planned behaviors through empirical study. In order for that, this study sets four research hypothesis. In the empirical findings, 3 research hypothesis except H2 (subjective norms have positive relations with entrepreneurial intention) are accepted in statistically. Considering research findings, students' planned behaviors, such as albeit, internship, getting some certifications to have been regards as far away from entrepreneurship have positive relation with entrepreneurial intention and implementation. Entrepreneurship education and knowledge regarding start-ups given by Universities or private institutions should provide information to create imagination new venture business with spontaneity instead of giving intented contents concerning entrepreneurship when taking into consideration of result of hypothesis 2. In order words, entrepreneurship education to provide the self-efficacy is the right track for students.

• Science of Emotion and Sensibility
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• v.10 no.3
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• pp.471-480
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• 2007

Negative emotions play an important function as to human's existence. In this research, we employed the audio-visual film clips to induce negative emotions and examined the classified responses in the autonomic nervous system(ANS) due to each negative emotion.30 adults(22.6 years $old{\pm}1.24$, 15 males and 15 females) took part in this experiment. Through the preliminary experiment, 2 minutes film's stimuli were selected as the emotion-induced stimuli. During the period when participants were viewing and listening to the selected movie, EDA and ECG were examined as soon as one stimulus was displayed, participants were tested by completing the psychological appraisals of their experienced emotion due to each emotional stimulus. With regard to the result of analyzing the psychological responses, each negative emotion appropriately and effectively induced its target emotion. While concerning the result of analyzing ANS responses, each negative emotion induced its respective activation in ANS. What is more, compared with other types of negative emotional stimuli, the scaring stimulus induced higher activation of the sympathetic nervour system(SNS) as to the indexes in EDh and ECG. This research made segmentation of ANS responses to each negative emotion, which has its significance.

• Journal of the Korean earth science society
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• v.40 no.5
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• pp.518-537
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• 2019

This study examined the implications of a place-based earth science program integrated with Mathematics. 11 pre-service earth science teachers and 22 middle school students participated in the service education activities of earth science for 30 hours focusing on the measurement of the earth's size through earth science experiments as part of the middle school curriculum. In order to minimize errors that may occur during the earth's size measurement experiments using Eratosthenes's shadows length method of the ancient Greek era, the actual data were collected after triangulation ratios were conducted in the locations of two middle schools: one in remote metropolitan and the other in rural area. The two schools' students shared the final estimate result. Through this process, they learned the mathematical method to express the actual data effectively. Participants, experienced the importance and difficulty of the repetitive and accurate data acquisition process, and also discussed the causes of errors included in the final results. It implies that a Place-Based Earth Science Program activity can contribute to students' increased-understanding of the characteristics of earth science inquiry and to developing their problem solving skills, thinking ability, and communication skills as well, which are commonly emphasized in science and mathematics in the 2015 reunion curriculum. It is expected that a place-based science program can provide a foundation for developing an integrated curriculum of mathematics and science.