• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.192-192
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• 2009

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.188-188
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• 2009

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.189-189
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• 2009

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2003년도 추계학술발표논문집 (중)
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• pp.911-914
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• 2003

D-DoS 공격을 차단하기 위해서는 AS 경계 라우터에 필터 설치가 필요하며, 이는 최소한의 라우터에 필터를 설치하기 위해 VC(Vertex Cover)를 찾아내는 NP-complete 문제로 귀결된다. 따라서 실제 AS 망구성의 특성을 이용해 이에 적합한 VC 근사기법을 찾아내는 알고리즘을 제안한다. 실험 결과, 제안된 알고리즘(Improved 'Approximated VC')은 기존의 'Approximated VC'에 의해 필요한 노드수의 26%를 줄였다.

• 한국인터넷방송통신학회논문지
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• 제9권2호
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• pp.137-144
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• 2009

본 논문은 GPS 신호를 기반으로하여 3D 배열 안테나를 사용한 전파의 도래각 (DoA : Direction of Arrival)을 추정한 후 빔 형성시의 재머 신호의 각도 퍼짐에의한 성능 비교에 관한 것이다. 배열 안테나를 사용하여 도래각을 추정한 후 공간 필터링에의해 도래 방향으로 빔을 형성하고, 다른 방향으로는 널링시킴으로서 수신 신호의 강도와 품질을 개선할 수 있지만 이 과정에서 다중 재머 신호에의한 각도 퍼짐으로 열화되는 성능이 얻어진다. 논문에서는 열화되는 성능의 비교를 위해 5 가지의 3D 배열 안테나를 제안하였고 도래각 추정은 MUSIC 알고리즘을, 빔 형성은 LCMV 알고리즘을 이용하였다. 또한 도래되는 재머 신호의 방위각과 앙각을 변화시키면서 BPSK 모뎀을 적용할 때 비트 오율을 계산하여 성능 비교를 하였다. 시뮬레이션 결과 Curved (B) 7-Element 형 3D 배열 안테나가 다른 안테나보다 성능이 가장 우월함을 알 수 있었다.

• 한국환경농학회지
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• 제42권1호
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• pp.63-70
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• 2023

Golden apple snails (Pomacea canaliculat) (GAS) are widely used for weed control in rice cultivation. However, concerns on the ecological risk of invasive GAS species are increasing. This study aimed to evaluate the overall impacts of GAS on weed control, abundance of aquatic animals and insects, and rice yield, in comparison with that from other biocontrol agents such as loach (Misgurnus mizolepis) and catfish (Silurus asotus), which are alternatives for biological weed control in rice paddy cultivation. Field experiments included five treatments; control, herbicide, GAS, loach, and catfish. During the rice growth, weed appearance and biological abundance were monitored, and at harvest, the rice yield was determined. Weed control efficiency was the highest for GAS treatment (100%), followed by that for herbicide (95.8%), loach (57.5%), and catfish treatments (31.7%). Insect abundance was considerably decreased in GAS treatment due to heavy weed removal, which affects the habitat of aquatic animals and insects. The amount of rice yield (unit: kg 10 a^-1) was in the order of GAS (798.9) > loach (708.1) = herbicide (700.7) > catfish (629.4) > control (496.0). Therefore, considering the weed control efficiency, biological abudance, and rice yield, loach could be a potential alternative for biological weed control in organic rice farming. However, the activity of the biocontrol agents are susceptible to environmental conditions; therefore, further studies under different conditions are essential to confirm these findings.

• 대한화장품학회지
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• 제27권1호
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• pp.53-72
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• 2001

Dry skin is caused mainly by the perturbation of stratum corneum lipids which affected by ageing, change of season, excess use of surfactant and the effect of disease like atopic dermatitis and psoriasis. Intercellular lipid structures in stratum corneum are responsible for the barrier function of mammalian skin. The major lipd classes that can be extracted from stratum corneum are ceramides, cholesterol and fatty acid, which make up approximately 50, 25, 10 percent of the stratum corneum lipid mass, respectively. Small amount of cholesterol sulfate, phospholipids, glycosylceramide and cholesterol esters are also present. Recent studies have shown that application of one or two these lipids to the perturbed skin delays barrier recovery; only equimolar mixtures allow normal recovery. We observed that barrier recovery rate was improved in hairless mouse by topical application of single neutral lipids (ceramide, free fatty acid, cholesterol) and lipid mixtures. Whereas the application of single lipid didn’t allows a significant enhancement comparing with normal barrier repair, the equimolar mixtures of 3 components(including synthetic pseudoceramide PC104) improved barrier repair, as assessed by the transepidermal water loss. At clinical study to the volunteers aged over sixty, skin dryness recuperated by the increase of moisture(capacitance) and the reduction of scaling. Utilization of physiologic lipid mixture containing natural ceramides or synthetic pseudoceramide could lead to new forms of topical therapy for the dryness and dermatoses(e.g., psoriasis, atopic dermatitis and irritant dermatitis).

• 산업경영시스템학회지
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• 제44권4호
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• pp.106-112
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• 2021

In the early 1960s, US Air Force lost missile launch bases during ICBM development by a defect in the missile design and operation plan. U.S. DoD realized the limitation of the existing accident prevention method. Therefore, the weapon development required system safety activity, and procurement projects of U.S. DoD applied MIL-STD-882(System Safety). Development projects of U.S. DoD more emphasized the importance of system safety after the space shuttle Challenger exploded in 1986. Currently, Airworthiness certification for military aircraft uses system safety to minimize accidents. The domestic defense aviation R&D projects also use the system safety for the airworthiness certification. However, non-aviation weapon R&D projects rarely applied system safety. This paper presents a system safety application method for domestic weapon R&D projects by studying the U.S. military standards/organizations and domestic defense aviation projects.

• 대한치과의사협회지
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• 제11권1호
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• pp.59-66
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• 1973

• 한국군사과학기술학회지
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• 제10권1호
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• pp.55-69
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• 2007

The paper provides the approach to apply formal methods to the development and certification criteria of defense safety/security-critical software. RTCA/DO-178B is recognized as a do facto international standard for airworthiness certification but lack of concrete activities and vagueness of verification/certification criteria have been criticized. In the case of MoD Def Stan 00-55, the guidelines based on formal methods are concrete enough and structured for the defense safety-related software. Also Common Criteria Evaluation Assurance Level includes the strict requirements of formal methods for the certification of high-level security software. By analyzing the problems of DO-178B and comparing it with MoD Def Stan 00-55 and Common Criteria, we identity the important issues In safety and security space. And considering the identified issues, we carry out merging of DO-178B and CC EAL7 on the basis of formal methods. Also the actual case studies for formal methods applications are shown with respect to the verification and reuse of software components.