• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4447-4454
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• 2013

In October 2011, a commercialized 100kW class floating photovoltaic system positive plant was installed at Hapcheon dam a multi-purpose reservoir the first time ever in the nation. Floating photovoltaic system differs in water float, mooring device and underwater cable process from land photovoltaic system. As for land and building photovoltaic power generation equipments, many installation cases and skilled experiences are available, and thus installation is not difficult. However, commercial power generation floating photovoltaic system, which is attempted for the first time in the nation, requires to be designed and installed through a series of processes like technical review and verification of data by process in comparison with similar cases. The structure of floating photovoltaic system, an equipment for float photovoltaic module and other electrical equipment, is required to withstand weather environments like wind or typhoon etc and yet not affect water quality negatively, and for implementation of this system, construction efficiency and economy etc should be considered comprehensively. In this paper, the techniques of installing floating photovoltaic structure, mooring device, underwater cable, electrical equipment and remote monitoring control system are explained. The 100kW floating PV system is operating with 15% average capacity factor.

• Resources Recycling
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• v.23 no.4
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• pp.58-68
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• 2014

The statistics showed that about 1 billion automobiles were registered and about 40million ELVs occurred on the world in 2010. So all advanced countries including EU had plan to increase the ELVs recycling rate up to 95% of total by 2015. The Korean government also established a target for raising up to 95% of ELVs recycling rate according to 'Act on the Resource Circulation of Electrical and Electronic Equipment and Vehicles'. Before being satisfied with the requirement of recycling of ELVs however, the problem is issued on the scraps of plastic and non-ferrous metals which are now being abandoned and reclaimed with no adequate reuse. Therefore, as a part of preceding investigation on the present state of ELVs recycling in the world, this preliminary investigation study was carried out focusing on the state of EU's disposal and management regulations of ELVs and SLF/ASR including the world trend of disposal and management regulations of ELVs and SLF/ASR.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.1
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• pp.131-138
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• 2003

With the Internet winning a huge popularity, there rise urgent problems which are related to Network Security Managements such as Protecting Network and Communication from un-authorized user. Accordingly, Using Security equipments have been common lately such as Intrusion Detection Systems, Firewalls and VPNs. Those systems. however, operate in individual system which are independent to me another. Their usage are so limited according to their vendors that they can not provide a corporate Security Solution. In this paper, we present a Hierarchical Security Management Model which can be applicable to a Network Security Policies consistently. We also propose a Policy Negotiation Mechanism and a Prototype which help us to manage Security Policies and Negotiations easier. The results of this research also can be one of the useful guides to developing a Security Policy Server or Security Techniques which can be useful in different environments. This study also shows that it is also possible to improve a Security Characteristics as a whole network and also to support Policy Associations among hosts using our mechanisms.

• Journal of Fashion Business
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• v.26 no.4
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• pp.112-122
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• 2022

The purpose of this study is to investigate the effect of using socks combined with EMS on ankle pain reduction and ankle function improvement in home training participants. In this study, the conductive fabric was combined using socks that can properly compress the ankle. First, VAS was measured during EMS training after fatigue was induced and compared with fatigue during rest. It was confirmed that the level of VAS after EMS training was lower than after rest and fatigue. It was also confirmed that EMS training, which combines EMS with socks, was effective in reducing pain. The experimental action is a measurement action of WBLT and lying posture, and the situation before and after EMS training was compared by performing 30 minutes on the treadmill to cause delayed muscle pain during exercise. As a result of this study, it was found that pain reduction and ROM function were improved when electrical stimulation was performed using EMS socks. It was also confirmed that the application of electrical stimulation to EMS socks effected on ankle fatigue and function improvement. From the study results, it is expected that wearing socks equipped with EMS significantly reduces ankle injuries and improves functional recovery for home training participants.

• Journal of Korea Society of Industrial Information Systems
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• v.29 no.1
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• pp.31-48
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• 2024

The domestic automotive industry must consider a strategic shift from traditional automotive component manufacturing to align with future trends such as connectivity, autonomous driving, sharing, and electrification. This research conducted topic modeling on R&D projects in the future automotive sector funded by the Ministry of Trade, Industry, and Energy from 2013 to 2021. We found that topics such as sensors, communication, driver assistance technology, and battery and power technology remained consistently prominent throughout the entire period. Conversely, topics like high-strength lightweight chassis were observed only in the first period, while topics like AI, big data, and hydrogen fuel cells gained increasing importance in the second and third periods. Furthermore, this research analyzed the areas of concentrated investment for each period based on topic-specific government investment amounts and investment growth rates.

• Journal of Advanced Navigation Technology
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• v.28 no.3
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• pp.300-308
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• 2024

Urban air mobility (UAM) is emerging as a revolutionary transportation solution to urban congestion and environmental issues. Especially, electric vertical take-off and landing (eVTOL) aircraft are expected to enhance urban mobility, reduce traffic congestion, and decrease environmental pollution. However, the successful implementation and operation of UAM systems heavily rely on advanced technological infrastructure, particularly in sensor technology. Among these, 3D light detection and ranging (LiDAR) systems are essential for detecting obstacles and generating pathways in complex urban environments. This paper focuses on the challenges of developing LiDAR-based perception solutions, emphasizing the importance and performance of object detection capabilities using 3D LiDAR. It integrates LiDAR data processing algorithms and object detection methodologies to experimentally validate the effectiveness of perception solutions that contribute to the safe navigation of aircraft. This research significantly enhances the ability of aircraft to recognize and avoid obstacles effectively within urban settings.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.539-548
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• 1995

The process of yolk absorption and the growth pattern of churn salmon, Oncorhynchus keta alevin were studied. Matured males and females of chum salmon were sampled from the Namdaechun River in the east coast of Korea, and then an artificial fertilization was carried out using their eggs and sperms. Fertilized eggs were incubated in controlled water temperature of $13^{\circ}C$ and samples of 40 alevins were randomly taken at just hatching and at every three days between 12 days alter hatching and yolk absorption. The means of total length and total weight of hatched alevins were respectively 1.97cm and 1.85g and the yolk absorption took about 33 days after hatching, based on the morphological measurement. Growth curves of total length, total weight and somatic weight were fitted well with the Gompertz growth model. However, the shrinking in yolk-sac length, yolk-sac weight, yolk-sac height and yolk-sac volume revealed a linear phenomenon until the absorption of yolk was completed. The relative growth of chum salmon alevin, such as the relationship between total length and total weight, or between total weight and yolk-sac weight, was also studied.

• Journal of Aquaculture
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• v.4 no.2
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• pp.85-95
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• 1991

Spawning inducement of flounder, Paralichthys olivaceus, was attemped by the control of water temperature and photoperiod from June 1, 1989 through January 5, 1990 (189 days) Water temperature was gradually decreased from $21.7^{\circ}C$ to $10.6^{\circ}C$ which was the minim biological temperature for spawning of flounder. Water temperature was increased asain to $15^{\circ}C$ gradually, and then maintained at this level through the end of spawning. Photoperiod was also changed gradually from 10L/14D in June 1, 1989 to 14L/10D in July 25, 1989. Spawning of the fish occurred from October 4, 1989 through January 5, 1990 (93 days). The average number of eggs spawned during the spawning season per female were 2.67 billion. The first spawning occurred on the 60th day after the time of minimun water temperature $10.6^{\circ}C$. The water temperature and photoperiod at the first spawning were $13^{\circ}C$ and 14L/10D respectively It took 71 days to spawn since the photoperiod had changed from 10L/14D to 14L/10D. Spawning period can be devided into three terms. The first term was continued for 30 days from the beginning of the spawning. The second term for 41 days was the major spawning period followed by the third term, the final period of the spawning, for 22 days. The percentage of average fertilization rate of the eggs in the first, second and third spawning terms were $37.4{\%},\;54.1\%\;and\;19.6\%$, respectively. Feeding rate was increased in the maturing period but, decreased in the spawing period. During the final spawning period, the abrubt decreasing of the feeding occurred again.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.05a
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• pp.11-11
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• 2009

종래의 산업폐수 처리기술로는 중금속 함유 폐수에 수용성의 금속염을 첨가하여 가성소다 혹은 소석회를 이용하여 pH를 조정하고 고분자 응집제를 첨가하여 금속의 수산화물을 생성시켜 이를 부상 혹은 침전시켜 Sludge화하여 제거하는 방법이 주로 사용되고 있다. 그 외 질소, 인, 유기물이 함유된 폐수의 경우에는 Biological Oxidation Techniques, 활성탄 흡착방식이 주로 채택되고 있다.[1-3] 이러한 폐수처리기술은 화학약품 사용량이 과다하고 이는 Sludge 생성량을 증대하고 2차 폐수처리가 필요로 하는 경우가 많고, 처리장이 면적이 넓어야 하고 대용량의 Sludge 제거창치가 필요하여 고비용의 처리공정으로 문제점을 가지고 있다.[2-3] 이에 본 연구에서는 이러한 기존 기술의 문제점을 보완할 수 있고 기존 기술로는 완벽하게 처리하기 곤란한 악성 폐수들에 대한 새로운 고도처리기술로 초전도 마그네트를 이용한 고구배 자기분리기술에 대한 기초연구를 하였다. 본 연구에서 사용한 고구배 자기분리 시스템은 무헬륨 전도냉각방식으로 자기분리를 위해 사용한 필터는 SUS 430 재질의 메쉬 형태로 제작하여 실험하였다. 또한, 자기분리 처리를 위한 전처리 공정으로는 응집제를 첨가하여 자기분리 효율을 높이고자 하였다. 자기분리 처리대상수로는 포항제철에 압연 강판에 사용되는 냉각수를 대상으로 자기분리 처리에 대한 효과를 실험하였다. 또한, 자기분리에 대한 특성을 평가하기 위해 강자성의 $Fe_3O_4$ 미세자성분말을 첨가하여 처리수내의 들어있는 유기물질에 대해 자기분리 자장 및 유속에 대한 처리효율을 미치는 영향을 조사하였다. 자기분리 처리는 1~6 Tesla에서 자기필터는 디스크 형태로 다층으로 연속적으로 적층하였으며, 처리유속은 1~4 l/min으로 하였다. 고농도인 처리폐수를 자가분리 인가 자장에 따라 처리하여 고농도에서는 70%, 저농도에서는 98 %까지 처리되었다. 또한, 자기분리용 필터는 SUS 430 재질의 mesh 망을 사용하였으며 인가자장 및 유속변화에 대한 실험 결과 탁도 및 농도는 필터 크기의 영향은 거의 차이가 없었으며 단지 인가자장 및 유속에 따라서 지수적으로 감소하였다. 자기분리된 용액 내 $Fe_3O_4$ 입도 분석 결과 자기분리 이전에 분포하던 $10\sim20\;{\mu}m$의 입자는 거의 제거되었으며 2 ${\mu}m$ 이하의 입자들은 실험 횟수에 따라 점점 직경이 작은 쪽으로 분포가 좁아졌으며, 마그네타이트의 자화율을 분석한 결과 약 0.8 Tesla에서 포화 되었으며 처리수의 탁도 및 농도가 자장에 따라 감소하는 것으 알 수 있었다.

• The Journal of Korean Philosophical History
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• no.58
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• pp.139-160
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• 2018

'Gyeokmulchiji' (格物致知), coming to knowledge based on the investigation of things) is a starting point for any study and politics of Confucianism. Much emphasis was placed on the conception of 'Gyeokchi' as a root of every learning and adminstration in the early Joseon period. As Confucianism established itself as a salient value system of the government, a mighty change and paradigm shift happened in its governmental system which had depended upon Buddhism up to that time. Thus, Confucian statecraft also stood out. Daehakyeonui (大學衍義) was preached as a model of regal learning and politics in the governmental agon, and its conceptual starting point was 'Gyeokchi.' The various interpretations and arguments about this concept shows the process in which Zhu Xi NeoConfucianism was deepened into Neo-Confucianism of Joseon's own. This conception reached the essence of 'Li' beyond the problem of cognitive subject and object, and provided a watershed which divided Giho (畿湖) and Yeongnam (嶺南) schools. Confucian method of study, which incorporates knowledge and practice, has great implications for our times when there are many voices of concern over humanities. The enhancement of universities and humanities is much needed to adjust the direction and pace of scientific technology, which is now entirely left with the logic of market. Accordingly, it is quite urgent for us to examine our object of learning again, which should integrate 'Sugi' (修己, cultivating oneself) with 'Chi-in' (治人, governing others), and knowledge with practice.