• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.2
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• pp.700-713
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• 2015

It is critical to design energy-efficient routing protocols for battery-limited mobile ad hoc networks, especially in which the energy-consuming MIMO techniques are employed. However, there are several challenges in such a design: first, it is difficult to characterize the energy consumption of a MIMO-based link; second, without a careful design, the broadcasted RREP packets, which are used in most energy-efficient routing protocols, could flood over the networks, and the destination node cannot decide when to reply the communication request; third, due to node mobility and persistent channel degradation, the selected route paths would break down frequently and hence the protocol overhead is increased further. To address these issues, in this paper, a novel Greedy Energy-Efficient Routing (GEER) protocol is proposed: (a) a generalized energy consumption model for the MIMO-based link, considering the trade-off between multiplexing and diversity gains, is derived to minimize link energy consumption and obtain the optimal transmit model; (b) a simple greedy route discovery algorithm and a novel adaptive reply strategy are adopted to speed up path setup with a reduced establishment overhead; (c) a lightweight route maintenance mechanism is introduced to adaptively rebuild the broken links. Extensive simulation results show that, in comparison with the conventional solutions, the proposed GEER protocol can significantly reduce the energy consumption by up to 68.74%.

• Journal of the Health Care and Life Science
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• v.9 no.1
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• pp.141-146
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• 2021

Determination of capsaicin, dihydrocapsaicin and nonivamide in pungent liquids of self-defense spray were studied. The nonivamide having almost same spicy taste with capsaicin have been containing a few amounts in natural products, it had called as synthetic capsaicin or PAVA, have used to flavorings for foodstuffs and incapacitating agents of riot controls. Nowadays, it has been occasionally found that the quality controls of a self-defense sprays were not properly due to flood of illegal self-defense sprays. Thus, the simple analytical method with gas chromatography is developed, it is identified whether the products which have contained synthetic capsaicin were marked like natural materials as well as the pungent ingredients in it obeyed with permissible concentration to human or not was investigated. Finally, the pungent components and amounts in some kinds of self-defense spray were investigated.

• Journal of Korean Society of Rural Planning
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• v.22 no.2
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• pp.67-75
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• 2016

This Research was carried out to investigate landscape characteristics of the traditional Chinese village through the landscape analysis. The Purpose of this study was to offer suggestions for improving Korea's traditional village scenery. This research was conducted by analysis about an important component of the landscape in Ping-shan traditional village. It was studied natural landscape, life landscapes, agricultural production landscapes and symbols landscape. This study was carried out through literature research, field research and interviews. The results of Chinese traditional village's landscape characteristic was First, Ping-shan traditional village was located on the basis of Feng-Shui settings. Second, Ping-shan traditional village was clan-based. Third, It is composed of a large green space on the outskirts of the village. Fourth, Ping-shan traditional village was a typical channel village. Fifth, Ping-shan traditional village was a living landscape with various features. sixth, Ping-shan traditional village was a lot of space to agricultural production, most of the arable land surround village. Suggestions for improving Korea's traditional village scenery are as follows ; First, proposes actively re-design on the base of defense fengshi landscape interpreted as a modern sense. Seconds, when large-scale farmland project is established in Korea, you can expect to gain knowledge from traditional Chinese village spacing. Thirds, It seems to require a study of the public space for festival. in the case of china, ancestral shrine space is center and space for festival. Fourth, It was important to seek knowledge about protection for frequent in flood plains in Korea's traditional village. Ping-shan traditional village was well-known for housing with contact water, connected channels and beautiful defense pond. Fifth, for improving Korea's traditional village scenery, we need to make various focus landscape features. Most of the visitors to Ping-shan traditional village was interested in the big and small beautiful landscapes and shelters.

• Journal of Internet Computing and Services
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• v.10 no.3
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• pp.51-60
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• 2009

This paper proposes a reliable 2-mode authentication framework for probabilistic key pre-distribution in Wireless Sensor Network (WSN) that guarantees the safe defense against different kinds of attacks: Hello flood attacks, Wormhole attacks, Sinkhole attack, location deployment attacks, and Man in the middle attack. The mechanism storing the trust neighbor IDs reduces the dependence on the cluster head and as the result; it saves the power energy for the authentication process as well as provides peer-to-peer communication.

• Journal of Wetlands Research
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• v.21 no.4
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• pp.305-311
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• 2019

Recently, global climate change causes abnormal weather and disaster countermeasures do not provide sufficient defense and mitigation because they were established according to the historical climate condition. Repeated torrential rains, in particular, are causing damage even in the robust urban flood defense system. Therefore, in this study, the change of runoff considering the spatial distribution of rainfall and urban characteristics was analyzed. For rainfall concentrated in small catchment, rainfall in the watershed must be accurately measured. This study is based on the rainfall data observed with Automated Surface Observing System (ASOS) and Automatic Weather Stations (AWS) provided by the Seoul Meteorological Administration. Effluent from the pumping station was estimated using the EPA-SWMM model and compared and analyzed. Catchments with rainwater pumping station are small with large portion of impermeable areas. Thus, when the ASOS data where is located from from the chatchment, runoff is often calculated using rainfall data that is different from rainfall in the catchment. In this study, the difference between rainfall data observed in the AWS near the catchment and ASOS away from the catchment was calculated. It was found that accurate rainfall should be used to operate rainwater pumping stations or forecast urban flooding floods. In addition, the results of this study may be helpful for estimating design rainfall and runoff calculation.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.4
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• pp.221-229
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• 2020

Naval ships could be seriously damaged by enemy attacks in battle. Moreover, this damage could be spread and deteriorated into a secondary accident. Secondary accidents that have adverse effects on naval ship's survivability, such as fire, flood, smoke extension, and patient occurrence, are defined as casualties. These casualties sharply degrade the survivability of naval ships. Furthermore, naval ships could be burned-out and sunk by casualties in isolated sea. Therefore, damage control and rapid suppression of the casualties in the naval ships is essential. This study was conducted in the establishment of suppression paths according to the characteristics of each casualty so that the developed system can support the rapid suppression in an emergency and even the training situation on a regular state. To establish the suppression paths, the two-dimensional numerical map is designed by converting the three-dimensional features of the naval ships, and the well known algorithms are compared to present the appropriate one for path finding problem on the naval ships. Finally, we devised a specific routing algorithm that fits the characteristics of each casualty in accordance with the Korean Navy's doctrines and handbooks of casualty suppression.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.373-378
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• 2008

기존에는 잠재위험도와 해당지역 하나의 강우관측소에서의 기왕최대강우량을 이용하여 계획빈도를 결정하였다. 그러나 기왕최대강우량은 이미 발생한 최대강우량이기 때문에 안전치를 고려해 산정한 계획빈도를 따라가지 못하였고, 잠재위험도에 따른 계획빈도의 범위가 매우 작은 문제점이 있었다. 따라서 본 연구에서는 문산천 유역의 기왕최대강우량과 잠재위험도를 이용하여 계획빈도를 산정하는데 필요한 가중치를 결정하였다. 본 연구에서는 수도권지역 6개의 기상청 강우관측소 강우량 자료를 사용하여 크리깅기법으로 공간분포를 시키고자 하였다. 또한, 기왕최대강우량으로 계획빈도를 연결시키는데 있어서 발생하는 문제점을 해결하기 위하여 계획빈도의 가중치를 산정하고자 하였다. 문산천 유역에 잠재위험도 산정에 따라 계획빈도를 결정한 결과, 크리깅기법으로 문산천 유역에 기왕최대강우량에 해당하는 계획빈도는 160년 정도이며, 회귀식으로 각 소유역별로 계획빈도를 산정한 결과 약 110년에서 120년까지 분포하였다. 이렇게 산정된 계획빈도를 공시지가와 홍수량으로 가중치를 구하여 소유역별로 분포시킨 계획빈도 값은 대략 100년에서 200년으로 산정되었다. 잠재위험도와 피해액 산정기법을 이용하여 문산천에 최적 홍수방어대안을 선정하고자 하였다. 최적 대안을 선정하기 위한 방법론을 제시하고 이에 따라 잠재위험도를 산정하고 유역 분담량을 결정하여 적합한 구조적 홍수방어시설물을 Decision Tree라는 의사결정을 통하여 계획하고 조합하여 3개의 적정 홍수방어대안을 선정하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.343-343
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• 2017

기후변화로 인하여 평균 기온 및 강수량이 증가하고 이에 따라 홍수의 발생 빈도가 증가한다. 기후변화에 따른 미래 예측은 기후변화 시나리오로 분석하고 있으며, 현재 사용하는 기후변화 시나리오는 2013년에 발간된 IPCC (Intergovernmental Panel on Climate Change) 5차 평가보고서(AR5)에서 2007년에 발간된 IPCC 4차 평가보고서(AR4)에 사용한 SRES(Special Report on Emission Scenario) 온실가스 시나리오를 대신하여 대표농도 경로 RCP(Representative Concentration Pathways)를 사용한다. 기후변화 시나리오에 따라 기온 상승률 및 강수량의 증가량, 극한 강우사상의 발생 빈도 및 발생 정도가 다르게 결정되며, 이에 따라 IPCC에서 제시하는 기후변화 취약성 평가 이론의 민감도 지수가 시나리오에 따라 증가하는 정도가 다르게 산정된다. 민감도 지수의 증가는 홍수위험지수의 증가로 이어지며, 이에 따라 치수대책 변화를 분석하여 치수안전도 개선 및 수재해에 의한 위험을 대비할 수 있다. 본 연구에서는 기후변화 시나리오에 따른 연평균강수량, 일최대강수량과 같은 극치 강수량과 치수 대책 변화 및 치수대책변수의 현황, 치수대책변수의 개선가능범위 분석을 통한 치수안전도 개선 효과를 분석하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.284-284
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• 2022

최근 세계적으로 급변하는 기후는 연 강수량이 여름에 집중되는 한국 강우 특성에 큰 영향을 미치고 있다. 특히 도시화된 대도시의 배수 시설 능력 부족은 돌발 강우, 국지성 집중 호우로 인한 침수 피해를 야기한다. 미국, 유럽, 일본 등의 선진국의 경우 대심도 저류배수터널을 설치하여 운영하고 있으며, 이에 대한 시설운영기준 및 매뉴얼 개발 등에 관한 연구가 활발히 이루어져 왔다. 그러나 국내에는 이와 같은 시설물에 대한 운영사례가 없고, 시설물 내 복잡한 수리 현상에 대한 수리모형 실험도 부족한 실정이다. 따라서 본 연구는 서울시 강서·양천 일대에 설치된 대심도 터널인 신월 빗물저류배수시설을 대상으로 선정하였으며, 안정적인 운영계획 수립을 위한 최적운영기준을 개발하고자 한다. 본 연구는 도시유역 강우유출모의에 적합한 XP-SWMM 모형을 활용하여 강우조건에 따라 달라지는 수직구별 유입유량, 도달시간 등의 유출특성을 반영하고 수문개방시간을 고려한 시설물 운영기준을 산정하였다. 본 연구의 결과는 도시유역 홍수예방을 위한 빗물저류배수시설의 안정적인 운영계획 수립 및 시설물 운영 매뉴얼 개발에 기여할 수 있을 것으로 기대된다.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.41 no.1
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• pp.35-46
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• 2023

This study investigated and analyzed ancient records on the type, planting background, and construction process of Gwanbang forest(關防林) planned for military defense during the Joseon Dynasty to find out the purpose, location, and planting species of Gwanbang forest. The research results were as follows. During the Joseon Dynasty, Gwanbang forests were created around various government facilities(關防施設), such as Eupseong(邑城), major government offices, camps, and fortifications, for the purpose of defending against enemies. Gwanbang forest includes Yeongaeglim(嶺阨林), which was created on the crest of a strategically important hill, and Military Forest created for military purposes. Most of the spirit forest was designated as Geumsan(禁山) and protected and managed, and the Gwanbang forest was created for various purposes such as shielding, flood damage and river bank erosion prevention as well as external defense. In addition, in order to continuously and efficiently produce wood, which is a material for ships, buildings, and agricultural tools, in most cases, large areas were created as mixed forests. As for the species constituting the Gwanbang forest, there are records of tangerine tree, which is effective for defense because it has thorns, and deciduous broad-leaved trees such as zelkova, elm, willow, david hemiptelea, and oak appear. In the case of Ganghwa island, which served as the defense of the capital and the royal family during the Joseon Dynasty, several records have confirmed that a forest densely planted with trifoliate orange was created for the purpose of Gwanbang forest to reinforce the defense of the outer fortress. Based on historical research in the literature, assuming that the natural monument 'Gapgotri tangerine tree in Ganghwa Island' was planted in the 30th year of King Sukjong(1704), the first record of planting trifoliate orange in Ganghwa Island, the maximum age is estimated to be more than 319 years.