• 대한토목학회논문집
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• 제37권1호
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• pp.61-72
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• 2017

자연재난에 따른 인명 및 재산피해의 증가로 재난 예방 및 대응에 대한 관심이 증가하고 있다. 우리나라에서도 1994년에서 2013년까지 지난 20년간 자연재해에 의한 피해액은 약 12조 원 중 대설에 의한 피해가 약 13%로 대설도 강우나 태풍보다는 작은 규모이나, 의미 있는 규모의 피해를 야기하고 있다는 것을 알 수 있다. 그러므로 본 연구에서는 대설피해액 추정을 위해 강원지역을 대상으로 기후관련 요인(최심적설량, 평균습도, 최저기온), 사회 경제적 요인(농촌지역인구밀도, 지역총생산량)을 독립변수로 하는 동시입력방식의 다중회귀모형을 구축하였다. 적용결과, 극한 값들에 대한 설명력이 다소 낮기는 하지만, 수정결정계수가 0.7 이상인 경우도 다수 존재하는 등 대설 발생 시 신속한 재난 대응에 활용하기에는 적용성이 충분하다고 판단된다.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.15-28
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• 2020

Urbanization and industrialization have caused increasing damage to national lands, and ecological restoration has proceeded without any specific assessment of this damage. The purpose of this study is to select indices to assess damaged areas through literature review and panel discussions, and to derive the importance of damaged area assessment indices by analyzing them through the Analytic Hierarchy Process (AHP). This study has derived, via literature review, six types of damage and a total of 18 related assessment indices. A total of 51 responses were collected from surveys and given to experts, and an AHP analysis conducted. As a result of the analysis, "Landform change (0.268)" was of the highest importance, with associated damage types as follows: "Soil contamination (0.193)", "Vegetation damaged (0.149)", "Surface soil loss (0.143)", "Change in soil physiochemical property (0.125)", and "Vegetation decline (0.122)". The analysis determined that the item of the highest importance in the overall assessment of damage was "Slope occurred area (0.100)", and that "Conductivity (0.022)" was of the lowest importance. This study can be presented as a criterion in determining the type and degree of damage in setting priorities for future ecological restoration projects.

• Smart Structures and Systems
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• 제6권5_6호
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• pp.561-578
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• 2010

This study proposes a multi-level damage localization strategy to achieve an effective damage detection system for civil infrastructure systems based on wireless sensors. The proposed system is designed for use of distributed computation in a wireless sensor network (WSN). Modal identification is achieved using the frequency-domain decomposition (FDD) method and the peak-picking technique. The ASH (angle-between-string-and-horizon) and AS (axial strain) flexibility-based methods are employed for identifying and localizing damage. Fundamentally, the multi-level damage localization strategy does not activate all of the sensor nodes in the network at once. Instead, relatively few sensors are used to perform coarse-grained damage localization; if damage is detected, only those sensors in the potentially damaged regions are incrementally added to the network to perform finer-grained damage localization. In this way, many nodes are able to remain asleep for part or all of the multi-level interrogations, and thus the total energy cost is reduced considerably. In addition, a novel distributed computing strategy is also proposed to reduce the energy consumed in a sensor node, which distributes modal identification and damage detection tasks across a WSN and only allows small amount of useful intermediate results to be transmitted wirelessly. Computations are first performed on each leaf node independently, and the aggregated information is transmitted to one cluster head in each cluster. A second stage of computations are performed on each cluster head, and the identified operational deflection shapes and natural frequencies are transmitted to the base station of the WSN. The damage indicators are extracted at the base station. The proposed strategy yields a WSN-based SHM system which can effectively and automatically identify and localize damage, and is efficient in energy usage. The proposed strategy is validated using two illustrative numerical simulations and experimental validation is performed using a cantilevered beam.

• Journal of Nutrition and Health
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• 제49권5호
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• pp.277-287
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• 2016

본 연구는 제5기 2차년도 국민건강영양조사 결과를 활용하여 한식 식품군의 총 페놀 함량, in vitro 항산화활성 및 인체세포를 이용한 ex vivo DNA 손상 감소효과를 비교하고, 각 지표간의 상관성을 분석하며, 한식의 총 식사 항산화능에 대한 각 식품군의 기여도를 알아보기 위해 수행되었다. 제5기 2차년도 국민건강영양조사 결과를 바탕으로 한식의 식물성 식품을 10가지 식품군 (곡류, 과일류, 채소류, 견과류, 김치류, 해조류, 감자류, 버섯류, 두류, 오일류)으로 분류한 후 각 식품군별로 총 섭취량의 1% 이상 섭취한 식품 84종을 한식의 식물성 식품으로 최종 선정하였다. 각 식품군의 총 페놀함량을 측정하였고, DPPH radical scavenging assay, TEAC assay, $ORAC_{ROO{\cdot}}$ assay를 사용하여 in vitro 항산화능을 측정하였다. 한식의 식품군별 항산화능 (dietary antioxidant capacity, DAC)은 in vitro 항산화활성 평균값과 각 식품군의 1일 섭취량을 고려하여 계산하였고 한식 TDAC는 각 식품군의 DAC로의 합으로 구하였으며, TDAC에 대한 각 식품군 항산화능의 기여도를 평가하였다. 인체 임파구에서의 ex vivo DNA 손상 정도는 comet assay를 사용하여 평가하였다. 한식 식품군의 총 페놀함량은 버섯류, 과일류, 채소류, 해조류, 김치류 등의 순으로 높았으며, 3가지 in vitro 실험법을 평균한 식품군의 항산화활성 순위는 버섯류, 해조류, 채소류, 김치류, 과일류 등의 순이었다. 각 식품군의 항산화활성에 식품섭취량을 고려하여 계산한 한식의 TDAC에 대한 식품군의 항산화능 기여도는 곡류가 33.4%로 가장 높았으며, 과일류 (23.9%), 채소류 (12.7%), 김치류 (11.2%) 등의 순으로 나타났다. 인체 임파구에서 ex vivo DNA 손상 보호효과는 버섯류에서 가장 높았으며, 그 다음 채소류, 과일류, 해조류, 김치류의 순으로 나타났다. 각 식품군의 페놀함량과 in vitro 항산화 활성, 그리고 ex vivo DNA 보호효과의 순위가 비슷하게 나타났으며 각 지표간의 상관성은 매우 높았다. 한식 식품군 중 버섯류, 과일류, 채소류, 해조류에서 총 페놀함량과 항산화 활성, DNA 손상 보호효과가 높게 나타났다. 각 식품군의 총 페놀함량과 in vitro 항산화 활성, ex vivo DNA 보호효과 지표 간의 상관성은 매우 높았다. 한식의 TDAC에 대한 식품군별 항산화능 기여도는 곡류가 가장 높았고, 그 다음이 과일류, 채소류, 김치류의 순이었다. 이러한 결과는 앞으로 한식의 우수성을 항산화 측면에서 밝히는데 매우 중요한 기초자료로 활용될 수 있을 것이다.

• Structural Engineering and Mechanics
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• 제67권6호
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• pp.587-601
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• 2018

Elevated water tanks are inverted pendulum type structures where drift limit is an important criterion for seismic design and performance evaluation. Explicit drift criteria for elevated water tanks are not available in the literature. In this study, probabilistic approach is used to determine maximum drift limit for damage state of yielding and damage state of collapse for the elevated water tanks supported on RC frame staging. The two damage states are defined using results of incremental dynamic analysis wherein a total of 2160 nonlinear time history analyses are performed using twelve artificial spectrum compatible ground motions. Analytical fragility curves are developed using two-parameter lognormal distribution. The maximum allowable drifts corresponding to yield and collapse level requirements are estimated for different tank capacities. Finally, a single fragility curve is developed which provides maximum drift values for the different probability of damage. Further, for rational consideration of the uncertainties in design, three confidence levels are selected and corresponding drift limits for damage states of yielding and collapse are proposed. These values of maximum drift can be used in performance-based seismic design for a particular damage state depending on the level of confidence.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.489-492
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• 2006

In this study we collected and analyzed cases where typhoons damaged coastal structures in Korea in the past 6 years, and hydraulic model tests were conducted in 2D flume. 2 areas where damage was concentrated were selected from ports that had suffered damage. The selected area was Kyungsang-namdo, where there are a total of 26 national ports. Damage to these two areas was organized by wind direction of the typhoons and the direction of the entrance of the port, and destruction patterns were analyzed. 2D hydraulic model tests were conducted of Deabyeun port, one of the damaged areas. Results were as follows: 1. As a result of survey, ports that had entrances that were open to winddirection of typhoon (Anti-clockwise direction) tended to be damaged mare, whereas ports that blocked by island and ports that were not open to wind direction of typhoon were not damaged. 2. As a result of the tests, there was damage that occurred when using the section of designed section, whereas there was no damage when the TTP weight was increased.

• 전기학회논문지
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• 제67권6호
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• pp.745-752
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• 2018

ICs(Integrated circuits) for nuclear power plant exposed to radiation environment occur malfunctions and data errors by the TID(Total ionizing dose) effects among radiation-damage phenomenons. In order to protect ICs from the TID effects, this paper proposes a radiation-hardening of the logic circuit(D-latch) which used for the data synchronization and the clock division in the ICs design. The radiation-hardening technology in the logic device(NAND) that constitutes the proposed RH(Radiation-hardened) D-latch is structurally more advantageous than the conventional technologies in that it keeps the device characteristics of the commercial process. Because of this, the unit cell based design of the RH logic device is possible, which makes it easier to design RH ICs, including digital logic circuits, and reduce the time and cost required in RH circuit design. In this paper, we design and modeling the structure of RH D-latch based on commercial $0.35{\mu}m$ CMOS process using Silvaco's TCAD 3D tool. As a result of verifying the radiation characteristics by applying the radiation-damage M&S (Modeling&Simulation) technique, we have confirmed the radiation-damage of the standard D-latch and the RH performance of the proposed D-latch by the TID effects.

• Natural Product Sciences
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• 제9권2호
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• pp.83-86
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• 2003

In the present study, Thespesia populnea (Malvaceae) bark was extracted with methanol and water. The extracts were vacuum dried to yield the respective methanol (MET) and aqueous extract (AET). The extracts were evaluated for hepatoprotective activity against carbon tetrachloride $(CCl_{4})$ induced liver damage at 2 dose levels (250 and 500 mg/kg). The biochemical parameters observed in serum were total bilirubin, alkaline phosphatase (ALP), serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) levels and total protein. Aspartate transaminase (AST), alanine transaminase (ALT) and total protein levels in liver were also evaluated. Histopathological study on the liver tissue was also performed. The extracts exhibited dose dependent reduction in total bilirubin, ALP SGOT, SGPT, AST, ALT and increase in total protein (serum and liver) levels. The extracts also exhibited only mild hepatocytic damage compared to the $CCl_{4}$ Treated group. MET was found to exhibit higher hepatoprotection than AET.

• 한국생산제조학회지
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• 제20권3호
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• pp.280-283
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• 2011

This study investigates the durability of car body and the safety of passenger inside car body in the case of the impact contact at passenger and car body. In case of front impact contact, maximum von Mises equivalent stress and principal stress become 3240.7MPa and 1634MPa respectively at the rear part of car body and the neck of dummy. And maximum total deformation occurred with 14.145mm at the hand of dummy. In case of side impact contact, maximum von Mises equivalent stress and principal stress become 7687.9MPa and 1690.7MPa respectively at the front part of car body and the lap of dummy. And maximum total deformation occurred with 16.414 mm at the foot of dummy. In case of rear impact contact, maximum von Mises equivalent stress and principal stress become 2366.6MPa and 1447MPa respectively at the front part of car body and the neck of dummy. And maximum total deformation occurred with 7.548mm at the rear part of car body. As the maximum von-Mises stress at side impact is shown with more than 700MPa as over two times at front or rear impact the danger of car body is increased. The great possibility of damage is shown at neck and hand of dummy with more than total displacement of 10mm.

• 대한한의학원전학회지
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• 제29권2호
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• pp.55-78
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• 2016

Objectives : The goal of this paper is to research what the name and concept of true-cold damage in Introduction to Medicine were originated from, and to trace the origin and changes of categorization of it after the book. Methods : Books concerned with true-cold damage were collected as many as possible, besides ones that Introduction to Medicine referred to, before the name, concept and categorization of it were searched and analysed. Results : The concept of true-cold damage in Introduction to Medicine, which had come from Lei Zheong Huo Ren Shu(類證活人書) in Song dynasty, was more similar to one of cold damage in a broad sense. The name that Li Chan appreciated, was derived from not Shang Han Zhi Ge(傷寒直格), but Shang Han Zheng Zhi Ming Tiao(傷寒證治明條) in Song dynasty. On the other hand, since Tao Hua(陶華) began to go into the details of cold damage in a narrow sense, most books had followed it. Whereas 11 diseases among 24 diseases of true-cold damage in Introduction to Medicine indirectly came from Lei Zheong Huo Ren Shu(12 diseases), 14 diseases among them were directly derived from Shang Han Zheng Zhi Ming Tiao(16 diseases) and 10 diseases were added containing syndromes of retained fluid and jaundice. The categorization in Introduction to Medicine scarcely adopted except Donguibogam(東醫寶鑑) and Uimunbogam(醫門寶鑑), while the categorization of true-cold damage in a narrow sense was mostly composed of 2 diseases, that is cold damage(傷寒) and wind damage(傷風). Conclusions : Li Chan had fulfilled the total conditions in which the concept, cause, symptoms, prescriptions and prognosis of 24 diseases in true-cold damage were equipped, in order to build up the system and categorization of it. To our regret, his scientific outcome had been hardly referred after his book.