• 한국가스학회지
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• 제17권1호
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• pp.1-6
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• 2013

$NO_x$ 배출허용기준이 강화되는 배출가스 규제에 대응하기 위한 대안으로서 제시되는 천연가스-수소 혼합연료 (HCNG)는 수소의 빠른 화염속도와 넓은 가연범위를 이용하여 후처리 장치 없이 규제치를 만족할 수 있어 디젤엔진에 비해 저공해성이나 가격경쟁력 측면에서 유리한 장점이 있다. 열효율 측면에서도 우수성을 인정받는 HCNG 연료는 수소 혼합율은 물론 운전영역별 운전전략에 따라 연소특성이 달라진다. 본 연구에서는 대형 천연가스 엔진에 수소혼합율 30%의 HCNG 연료를 적용하여 운전영역별 안정적인 연소특성 및 배출가스 특성을 살펴봄으로써 상용화 가능성과 운전전략을 포함한 기술 개발방향에 대해 검토하고자 하였다.

• Journal of Multimedia Information System
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• 제1권2호
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• pp.101-110
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• 2014

The purpose of this research is to extend Ad-hoc network system lifetime with the proposed routing protocol which has considered hop lifetimes of the nodes while guaranteeing QoS in the establishment process of Ad-hoc network communication paths. Based on another power aware routing system that proposed in the advanced research [1], we are proposing an alternative power aware routing system in which nodes' hop lifetimes are compared in order to extend the lifetime of an Ad-hoc network system and delay factors have been considered for the assurance of QoS. The research of the routing protocol in this paper, which aims to maximize the system survival time considering power consumption status during the path searching in MANET and pursues the mechanism that controls hop delays for the same reason, can be applied to the study of WSN. The study concerning such phenomena is essential so that the proposed protocol has been simulated and verified with NS-2 in Linux system focusing on the lifetimes of the hops of the nodes. Commercialization of smart devices and arrival of the ubiquitous age has brought about the world where all the people and things are connected with networks. Since the proposed power aware method and the hop delay control mechanism used to find the adequate communication paths in MANET which mainly uses batteries or in WSN, they can largely contribute to the lifetime extension of the network system by reducing power consumptions when utilized for the communications attempts among soldiers during military operation, disaster areas, temporary events or exhibitions, mobile phone shadow areas, home networks, in-between vehicle communications and sense networks, etc. This paper presents the definitions and some advantages regarding the proposed outing protocol that sustain and extend the lifetime of the networks.

• 한국재료학회지
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• 제30권4호
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• pp.197-203
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• 2020

Abdominal organs are the most vulnerable body parts under vehicle trauma, and there is high mortality from acute injuries in accidents. There are various ways to reduce this high mortality; one method is Resuscitative Endovascular Balloon Occlusion of the Aorta, which has recently become very popular as a minimally invasive alternative in the emergent management of patients with non-compressible hemorrhages below the diaphragm. However, high safety factor for patients is applied in actual clinical practice because there is no exact standard for the operating time. Therefore, in this study, the effects of the mechanical behavior of organ tissues for the duodenum, kidney, and liver on the operating time of Resuscitative Endovascular Balloon Occlusion of the Aorta is investigated in order to obtain data needed to establish standards of operating time. In characteristic analysis of organ tissues, uniaxial tensile test and compression test are conducted according to the operating time.

• Journal of Forest and Environmental Science
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• 제33권3호
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• pp.187-196
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• 2017

The use of unmanned aerial vehicles (UAV) for the estimation of tree height is gaining recognition. This study aims to assess the effectiveness of tree height estimation of Pinus densiflora Sieb. et Zucc. and Pinus koraiensis Sieb. et Zucc. using digital surface model (DSM) generated from UAV-acquired imageries. Images were taken with the $Trimble^{(R)}$ UX5 equipped with Sony ${\alpha}5100$. The generated DSM, together with the digital elevation model (DEM) generated from a digital map of the study areas, were used in the estimation of tree height. Field measurements were conducted in order to generate a regression model and carry out accuracy assessment. The obtained coefficients of determination (R2) and root mean square error (RMSE) for P. densiflora (R2=0.71; RMSE=1.00 m) and P. koraiensis (R2=0.64; RMSE=0.85 m) are comparable to the results of similar studies. The results of the paired two-tailed t-test show that the two tree height estimation methods are not significantly different (p-value=0.04 and 0.10, alpha level=0.01), which means that tree height estimation using UAV imagery could be used as an alternative to field measurement.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 춘계학술대회 논문집
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• pp.423-428
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• 2005

광범위한 컨테이너 무역의 빠른 성장률로 인하여, 모든 주요항만은 계획된 수용능력 수요에 대처해야하는 압력에 처해있다. 이러한 문제들을 해결하기 위한 결과로서, 컨테이너 보관과 터미널 용량에 대한 수용능력을 개선하고 성장수요를 찾아야한다. 더구나, 구체적 조정순서 재공학은 세계적으로 항공기, 선박회사, 터미널 그리고 창고기업체들의 상세한 계획과 공급이 연쇄 관리자들을 위하여 현재 반드시 필요한 목표이다. 따라서 이 논문의 목적은 항만이송시스템들의 성능평가를 실행하기 위한 3차원 시뮬레이터를 개발하는 것이다. 개발되어진 3차원 시뮬레이터 시스템은 제안된 전체 시스템의 유효성을 측정하게 되고 실제 존재하는 것들과 비교되어진다. 또한 성능 해석 변화들은 이러한 것들을 비교함으로서 정의되어진다.

• 한국ITS학회 논문지
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• 제2권1호
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• pp.75-84
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• 2003

도로 교통 상황을 감시하고 교통 정보를 추출하는 현재의 기술은 고가이며 설치하기가 어려운 하드웨어에 의존하고 있다. 비디오 카메라와 컴퓨터 비죤 기술의 이용은 기존의 방법의 새로운 대안이 될 수 있다. 비디오 카메라를 이용한 교통 정보 추출은 최근의 교통 운영 시스템의 중요한 열쇠이다. 본 논문에서는 비디오 카메라를 이용한 영상처리 기술을 적용하여 교통 정보를 추출하는 방법을 제안하였다. 제안된 방법에서는 주변 환경에서 여러 가지 잡음으로 인한 오 인식을 제거하기 위하여 적응적 배경영상 갱신 방법을 사용하였다. 또한 교통정보 추출 방법에서는 거리 값을 정의하여 검색구간을 통과하는 차량의 점유율을 통해 교통변수를 구하고, 이를 이용하여 8개의 교통상태를 정의하여 교통량을 측정하였다. 제안된 방법은 도심의 교통상황 데이터를 이용하여 실험하였다.

• 대한한의학회지
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• 제39권1호
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• pp.63-74
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• 2018

Objectives: Periodontitis is an inflammatory disease with the destruction of periodontal ligament, alveolar bone loss and inflammation of gingva, leading to teeth loss. Eclipta prostrata L. (Ecliptae Herba) has been used to treat the inflammatory disease as a Korean traditional medicine. The aim of this study is to investigate the effects of E. prostrata L. on periodontitis. Methods: E. prostrata L. was extracted with water and lyophilized. The aqueous extract of E. prostrata L. (EP) was topically applied to the periodontal lesion for 2 weeks. To induce the periodontitis, a 3-0 nylon ligature was placed around the cervix of the lower first molar in rat. Rats were divided into 3 groups (n = 7); NL group (non-ligatured and non-treated), L group (ligatured and vehicle-treated) and EP group (ligatured and EP-treated). After sacrifice, the mandibles was dissected and stained with methylene blue solution to analyze the alveolar bone loss. The expression of MMP-9 was determined in gingival tissues. To confirm the effect of EP on recovery of gingiva, mRNA expressions of type I pro-collagen and MMP-9 levels were investigated in LPS-treated HS68 fibroblast cells. In addition, inflammatory mediators were evaluated in LPS-treated RAW264.7 cells. Results: Alveolar bone loss was significantly inhibited by EP treatment. The mRNA expression of MMP-9 was attenuated in rats treated with EP. In addition, treatment with EP increased the expression of type I pro-collagen, while the expression of MMP-9 was decreased in LPS-stimulated HS68 fibroblast cells. Furthermore, EP down-regulated the LPS-induced IL-6, $TNF-{\alpha}$, COX-2 and iNOS production in RAW264.7 cells. Conclusions: These results suggest that EP have ameliorative effects on periodontitis through inhibiting alveolar bone loss and modulating the inflammatory mediators. Therefore, E. prostrata L. may be an alternative on patients with periodontitis.

• 무역상무연구
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• 제59권
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• pp.27-57
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• 2013

Traditionally construction has been an industry that favoured ADR over formal litigation due to the complexity of technical issues. However, over the past decade construction arbitration has come under increasing attack for its rising costs and growing delays, and expansion of arbitration processes to the point that those processes are approaching the more complex and formal processes followed to resolve disputes litigation. As a result, parties are looking for new methods of resolving their disputes in a more efficient and economical manner, such as ODR. A review of the history of ODR and the practical applications of ODR in use today lead to the conclusion that the concept of ODR for construction dispute resolution appears to be possible and realistic. The advantages seem to outweigh the disadvantages, especially given the solutions suggested to overcome many of the disadvantages. While ODR may not be a realistic venue for large complex construction cases, it may be just the ideal venue for smaller and simple construction disputes. In conclusion, given the advantages that ODR arbitration does offer, the most realistic use of ODR in the short term would involve disputes consisting of a simple, one-dimensional dispute within which the parties can stipulate to the facts in the case. In such simple disputes ODR may be not only an appropriate vehicle within which the dispute can be resolved; it might be more easily accepted by the parties as the preferred platform for resolution. Hopefully, international institutions of arbitration will be successful in their development of a international standards and platform fir disputes that can be adapted for use in construction and will serve as the first step in developing ways to handle small construction claims, thereby allowing parties to resolve their disputes in a faster and more economical manner.

• Molecular & Cellular Toxicology
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• 제5권1호
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• pp.58-66
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• 2009

The 2-year rodent carcinogenicity test involves long-term, repetitive dosing of animals that is both time consuming and expensive. Alternative approaches have been attempted using specific transgenic or knockout mice or toxicogenomics to predict carcinogenicity without conducting a 2-year rodent test. In addition, toxicogenomic analysis of carcinogen-treated animals could also enhance our understanding of molecular mechanisms and aid in the diagnosis of acute toxicity induced by carcinogens. Therefore, we investigated transcription profiles after administering the carcinogens 4,4-dimethylformamide (DMF) and 4-biphenylamine (ABP). BALB/c male mice were treated once with DMF (650 mg/kg i.p.) or ABP (120 mg/kg p.o.). Standard blood biochemistry and histological changes were observed. Gene expression profiles in the livers of mice treated with either vehicle or the carcinogens were analyzed using the Affymetrix $GeneChip^{(R)}$ assay. In all, 1,474 differentially expressed genes in DMF- or ABP-treated mice were identified as being either up- or down-regulated over 1.5-fold (P< 0.01), and these genes were analyzed using hierarchical clustering and Ingenuity Pathways Analysis. Of these, 107 genes were consistently regulated in both carcinogen-treated groups. Genes associated with cancer were upregulated (Por, S100a10, Tes, Ctcf, Ddx21, Eapp, Nel, and Pa2g4) or downregulated (Cbs and Gch1). Toxicological function analysis also identified genes involved in organ toxicity, including hepatotoxicity. These data may help to identify molecular markers for acute hepatotoxicity induced by carcinogens.

• 한국음향학회지
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• 제37권4호
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• pp.248-255
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• 2018

세단 타입에 비해 해치백 타입의 차량은 실링구조 확보에 어려움이 있기 때문에 후석에서 느껴지는 차폐성능이 열세한 것으로 알려져 있다. 차량의 차폐감 확보를 위해 강건한 실링 시스템과 충분한 흡음/차음 성능이 요구되지만 준중형 이하 세그먼트에서는 원가, 중량의 제약으로 인해 충분한 흡차음 사양 적용에 제한을 받고있어 효율적인 흡차음 사양의 적용이 요구되고 있는 실정이다. 본 연구에서는 정량적인 측정과 비교, 분석이 가능한 파워기반 소음감소(Power Based Noise Reduction, PBNR) 기반의 차음 윈도우 평가를 통해 준중형 해치백 차량의 후석 소음원의 전달 경로를 분석하고 후석 차폐성능 확보를 위한 흡차음 대안을 제시하였다.