• Asian-Australasian Journal of Animal Sciences
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• 제32권3호
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• pp.309-319
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• 2019

Phytochemicals which exist in various plants and fungi are non-nutritive compounds that exert numerous beneficial bioactive actions for animals. In recent years following the restriction of antibiotics, phytochemicals have been regarded as a primal selection when dealing with the challenges during the producing process in the poultry industry. The selected fast-growing broiler breed was more fragile when confronting the stressors in their growing environments. The disruption of oxidative balance that impairs the production performance in birds may somehow be linked to the immune system since oxidative stress and inflammatory damage are multi-stage processes. This review firstly discusses the individual influence of oxidative stress and inflammation on the poultry industry. Next, studies related to the application of phytochemicals or botanical compounds with the significance of their antioxidant and immunomodulatory abilities are reviewed. Furthermore, we bring up nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and nuclear factor kappa B ($NF-{\kappa}B$) for they are respectively the key transcription factors involved in oxidative stress and inflammation for elucidating the underlying signal transduction pathways. Finally, by the discussion about several reports using phytochemicals to regulate these transcription factors leading to the improvement of oxidative status, heme oxygenase-1 gene is found crucial for Nrf2-mediated $NF-{\kappa}B$ inhibition.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.523-526
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• 2015

In recent years, building commissioning has often been part of a standard delivery practice in construction, particularly in the high-performance green building market, to ensure the building is designed and constructed per owner's requirements. Commissioning, therefore, intends to provide quality assurance that buildings perform as intended by the design and often helps achieve energy savings. Commissioning, however, is not as widely adopted as its potential benefits are perceived. Owners are still skeptical of the cost-effectiveness claims by energy management and commissioning professionals. One of the issues in the current commissioning practice is that not every project is guaranteed to benefit from the commissioning services. This, coupled with its added cost, the commissioning service is not acquired with great acceptance and confidence by building owners. To overcome this issue, this paper presents a unique methodology to enhance owner's predicting capability of the degree of success of commissioning service using the Bayesian theorem. The paper analyzes a situation where a future building owner wants to use a pre-commissioning in an attempt to refine the success rate of the future commissioned building performance. The author proposes the Bayesian theorem based framework to improve the current commissioning practice where building owners are not given accurate information how much successful their projects are going to be in terms of energy savings from the commissioning service. What should be provided to the building owners who consider their buildings to be commissioned is that they need some indicators how likely their projects benefit from the commissioning process. Based on this, the owners can make better informed decisions whether or not they acquire a commissioning service.

• Journal of Information Processing Systems
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• 제20권2호
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• pp.239-251
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• 2024

Coronavirus disease 2019 (COVID-19) has severely curtailed travelers' willingness to carpool and complicated the psychological processing system of travelers' carpooling decisions. In the post-COVID-19 era, a two-stage decision model under dynamic decision scenarios is constructed by tracking the psychological states of subjects in the face of multi-scenario carpooling decisions. Through a scenario experiment method, this paper investigates how three psychological variables, travelers' psychological distance to COVID-19, anticipated regret, and experienced regret about carpooling decisions, affect their willingness to carpool and re-carpool. The results show that in the initial carpooling decision, travelers' perception gap of anticipated regret positively predicts carpooling willingness and partially mediates between psychological distance to COVID-19 and carpooling willingness; in the re-carpooling decision, travelers' perception gap of anticipated regret mediates in the process of experienced regret influencing re-carpooling willingness; the inhibitory effect of experienced regret on carpooling in the context of COVID-19 is stronger than its facilitative effect on carpooling willingness. This paper tries to offer a fact-based decision-processing system for travelers.

• 유변학
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• 제10권4호
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• pp.217-226
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• 1998

단섬유 강화 고분자의 사출성형시 고분자 수지의 유동에 의하여 섬유배향이 필연적으로 일어나며, 섬유배향에 의한 이방성 (anisotropy)은 최종성형물의 품질과 기계적인 특성 등에 많은 영향을 미친다. 사출공정 중에서 충전과정(filling stage)은 섬유배향에 지배적인 역할을 하므로, 충전과정의 유동장을 정확하게 해석하는 것은 매우 중요하다. 형상이 복잡한 캐비티(cavity)와 다중 캐비티에서는 먼저 충전이 완료되어 현탁액(suspension)이 압축을 받고 있는 영역들이 존재하게 된다. 기존의 방법처럼 사출성형의 충전과정을 비압축성 유동으로 가정하면 정확한 유동장을 계산할 수 없다. 본 연구에서는 충전과정에서 압축성을 고려한 혼합 유한요소법/유한차분법을 이용하여 유동장을 계산하였다. 충전이 완료되는 순간에서, 이차배향텐서에 대한 배향변화방정식을 4차 Runge-Kutta 방법을 이용하여 해석함으로써 3차원 섬유배향장을 예측하였다. 충전시간이 다른 4개의 캐비티를 갖는 금형을 제작하여 충전과정에서 압축성 효과를 고려한 수치해석 결과가 실험과 잘 일치함을 보였다. 또한, 압축성과 비압축성 유동장에서 이론적으로 계산된 섬유배향의 차이를 정성적 및 정량적으로 비교하였다.

• 디지털콘텐츠학회 논문지
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• 제11권4호
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• pp.479-486
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• 2010

문화산업에 대한 경제적, 문화적 가치가 재조명되면서 지역문화자원을 디지털콘텐츠로 개발하고 브랜드화하려는 지방자치단체들이 증가하고 있다. 그러나 지자체의 모든 문화콘텐츠사업이 성공하는 것은 아니다. 공무원, 참여기업, 주민의 상생구조를 기반으로 한 지속적인 성장 동력화의 모델로 발전시켜야 성공할 수 있다. 치밀한 기획과 사업설계를 통해 안정적인 추진계획 실현이 성공의 열쇠다. 또한 원천소스와 시장의 분석, 스토리텔링, 콘텐츠 개발과 브랜드화 전략전개, 그리고 단계별 결과분석에 따른 OSMD(One-Source Multi-Device) 및 OSMU(One-Source Multi-Use) 전략 전개가 성패를 좌우한다고 할 수 있다. 따라서 본 논문에서는 국내 최대 규모의 민 관 합작 콘텐츠사업이며 OSMD, OSMU의 대표적 사례인 전남 장성군의 '홍길동 문화콘텐츠사업'을 분석하여 지역문화자원의 브랜드화 성공전략을 연구하였다. 이미 완료된 1차 사업을 대상으로 홍길동 문화자원의 발굴과 단계별 콘텐츠화 과정 및 브랜드화의 전략모델을 분석하고, 진행과정의 문제점을 연구함으로써 지역문화자원을 브랜드화하려는 지방자치단체 및 문화콘텐츠 기업에게 모범적인 접근방향을 제시하고자 한다.

• Strategy21
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• 통권31호
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• pp.57-84
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• 2013

North Korea's continuous threats and provocative behaviors have aggravated tension on the Korean peninsula particularly with the recent nuclear weapons test. South Korea's best way to cope with this situation is to maintain the balance among three policy directions: dialogue, sanctions, and deterrence. Among the three, I argue that deterrence should be prioritized. There are different sources of deterrence such as military power, economic power, and diplomatic clouts. States can build deterrence capability independently. Alternatively, they may do so through relations with other states including alliances, bilateral relations, or multilateral relations in the international community. What South Korea needs most urgently is to maintain deterrence against North Korea's local provocations through the enhancement of independent military capability particularly by addressing the asymmetric vulnerability between militaries of the South and the North. Most of all, the South Korean government should recognize the seriousness of the negative consequences that North Korea's 'Nuclear shadow strategy' would bring about for the inter-Korea relations and security situations in Northeast Asia. Based on this understanding, it should develop an 'assertive deterrence strategy' that emphasizes 'multi-purpose, multi-stage, and tailored deterrence whose main idea lies in punitive retaliation.' This deterrence strategy requires a flexible targeting policy and a variety of retaliatory measures capable of taking out all targets in North Korea. At the same time, the force structures of the army, the air force, and the navy should be improved in a way that maximizes their deterrence capability. For example, the army should work on expanding the guided missile command and the special forces command and reforming the reserve forces. The navy and the air force should increase striking capabilities including air-to-ground, ship-to-ground, and submarine-to-ground strikes to a great extent. The marine corps can enhance its deterrence capability by changing the force structure from the stationary defense-oriented one that would have to suffer some degree of troop attrition at the early stage of hostilities to the one that focuses on 'counteroffensive landing operations.' The government should continue efforts for defense reform in order to obtain these capabilities while building the 'Korean-style triad system' that consists of advanced air, ground, and surface/ subsurface weapon systems. Besides these measures, South Korea should start to acquire a minimum level of nuclear potential within the legal boundary that the international law defines. For this, South Korea should withdraw from the Nuclear Non-proliferation Treaty. Moreover, it should obtain the right to process and enrich uranium through changing the U.S.-South Korea nuclear cooperation treaty. Whether or not we should be armed with nuclear weapons should not be understood in terms of "all or nothing." We should consider an 'in-between' option as the Japanese case proves. With regard to the wartime OPCON transition, we need to re-consider the timing of the transition as an effort to demonstrate the costliness of North Korea's provocative behaviors. If impossible, South Korea should take measures to make the Strategic Alliance 2015 serve as a persisting deterrence system against North Korea. As the last point, all the following governments of South Korea should keep in mind that continuing reconciliatory efforts should always be pursued along with other security policies toward North Korea.

• 한국산학기술학회논문지
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• 제19권12호
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• pp.677-685
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• 2018

건설공사에서 공정관리는 기본적으로 가장 중요한 단계이며, 효율적인 공정관리를 위해서는 합리적 공정표 작성이 우선시 되어야 한다. 설계단계에서는 기상조건과 현장 특성을 고려한 다양한 조건과 공법의 비교 검토를 통해 최적의 공사 기간을 산정할 수 있으나, 기획단계에서 기본적인 자료(D/B) 분석만으로는 효율적 공법 선정과 적정한 공사 기간 산정이 어렵다. 따라서, 기획단계에서 기존시가지의 공동구 건설시 표준공기 분석을 위하여, 본 논문에서는 공동구 형식을 개착식 및 터널식으로 구분하고, 각 형식의 특성과 기존시가지의 조건을 고려한 공법을 선정 하도록 하였다. 합리적인 공기 계산을 위하여 외부 공사에 영향을 주는 기상조건을 고려하여 년 간 가동율을 산정 하였으며, 개착식은 RC 공법/터널식은 Shield TBM 공법에 대한 단위공정을 분석하였다. 각 단위공정을 종합하여 연장 1,200m, 환기구 200m 간격으로 가정한 공사의 표준공기를 산정한바, 개착식은 893일, 터널식은 616일이 소요되는 것으로 분석 되었다. 본 연구의 결과는 기획단계에서 보다 쉽게 공동구 형식 선정과 표준공기 산정에 도움이 될 것이며, 추후 설계단계에 연계하면 공정 및 공사비 산정이 용이할 것으로 판단된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권2호
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• pp.137-145
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• 2000

Carcinogenesis is a multi-stage process that generally consists of at least three steps; initiation, promotion, and progression. If one of these carcinogenic steps were suppressed or delayed, the cancer could be prevented. Cancer chemoprevention is defined to be inhibition or reversal of the carcinogenic process by the specific chemical agents and is a novel approach to cancer management alternative to conventional chemotherapy. Chlorophylln(CHL), a water-soluble derivative of chlorophyll, containing sodium and copper, has been known to be strong antimutagen in several test systems, but its mechanism of antimutagenic action is unknown. In the present experiment, the possibility of CHL as chemopreventive drugs on 7,12-dimethylbenz[a]anthracene(DMBA)-induced hamster buccal pouch carcinogenesis was investigated by mutagenicity test, carcinogenicity test, and frequency or spectrum of H-ras mutations in the both of DMBA-induced and chlorophylln-pretreated-DMBA induced tumor by polymerase chain reaction and non-isotopic restriction fragment length polymorphism. The treatment of CHL reduced the yields and multiplicity of the 0.5% DMBA-induced tumor, 86% to 62.5% and $3.7{\pm}0.6$ to $1.4{\pm}0.3$, respectively. The occurrence of histidine revertant by $20{\mu}mole$ DMBA was inhibited 25.6 to 81.7% by 1 to $5{\mu}M$ CHL in a dose-dependent manner. The mutation rates of H-ras gene in DMBA-induced and CHL-pretreated-DMBA induced tumor were 96%, 94% of which the most mutations were in codon 12/13. These results suggest that CHL inhibits the carcinogenic action of DMBA by the formation of complex between CHL and DMBA or the inhibition of the activation of DMBA in vivo. But CHL did not affect the mutation rates or its spectrum in already formed tumor.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2001년도 학술대회지
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• pp.96-101
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• 2001

단일지역 국내 최대규모의 대형복합건설공사인 인천국제공항 건설사업은 환경 및 특성상 태동단계에서부터 사업관리체계 도입의 필요성이 제기되었고 94년 12원 사업관리용역계약이 체결됨과 더불어 본격적인 사업관리체계 구축 및 운영에 착수할 수 있었다. 사업관리용역계약이 체결될 시점에서는 국내의 건설관련법규가 이를 뒷받침하지 않은 상태여서 도입효과에 대한 논란이 많았으며 또한 CM에 대한 인식 및 인프라가 매우 미흡했기 때문에 실제 사업에 적용시켜 운영하는 과정에서는 적지 않은 문제점이 발견되는 등 매우 어려운 여건이었다. 그럼에도 불구하고 사업목표를 성공적으로 달성할 수 있었던 것은 학계와 산업계의 지대한 관심과 더불어 종사자들의 헌신적인 노력이 있었기에 가능했다. 본 고에서는 인천국제공항의 사업관리체계 적용과정에서 나타난 제반 문제점을 분석하여 보다 현실적이고 바람직한 사업관리체계의 정착방안을 제시함으로써 국내에서 CM제도가 보다 다른 시일 내에 올바르게 정착될 수 있는 환경 조성에 일조 하고자 한다.

• 대한기계학회논문집B
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• 제26권2호
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• pp.288-301
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• 2002

A vacuum freeze drying experiment of skim milk solution in a cylindrical container is conducted to investigate the multi-dimensional drying characteristics of the process during the primary drying stage. Temperature histories at several positions are measured under the same process condition that is carefully controlled. Then the measured temperature histories at different positions are combined to produce instantaneous temperature distribution fields inside the cylindrical container. Along with the temperature measurement, the mass reduction history of the skim milk solution is also measured. From the measured temperature distribution curved configurations of sublimation interfaces and 2-dimensional heat transfer is inferred. The freeze drying under the present experimental setup is simulated with a calculation program that is based on a finite volume method with a moving grid system. Good agreements between the numerical and experimental results are observed. The present experimental results and the numerical approaches can be useful information in developing the analysis tools for practical vacuum freeze drying processes.