• Title/Summary/Keyword: resistance management

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동결/해동 열사이클이 PEFC의 GDL/MEA에 미치는 영향 (Freeze/Thaw cycle effects on GDLs and MEAs of PEFC)

  • 임남윤;박구곤;박진수;윤영기;이원용;임태원;김창수
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 춘계학술대회
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    • pp.96-98
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    • 2006
  • Proper water management is vital to achieve high performance and durability of PEFC (Polymer Electrolyte Fuel Cell). The effects of the residual water from PEFC after purge in shut-down processes on GDL/MEAs were investigated with freeze/thaw cycles Freeze/thaw cycle tests were conducted with single cells which were designed from transparent acryl plates. Single cells which contain several amount of residual water were cycles from $80^{\circ}C$ to $-28^{\circ}C$. The resistance changes of the single cells which have various amount of residual water were evaluated by ac-impedance analysis with 24 times of freeze/thaw cycles. Also, after the freeze/thaw cycles, the property changes were characterized by visual methods such as SEM, EPMA. Though it was difficult to observe noticeable property changes in the visual characterizations, the resistance of cells dramatically increased with the amount of remained water.

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Cultivar Evaluation for Red Pepper under Organic Crop Management in Korea

  • Won, J.G.;Jang, K.S.;Hwang, J.E.;Kwon, O.H.;Jeon, S.G.;Park, S.G.
    • 한국유기농업학회지
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    • 제19권spc호
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    • pp.195-198
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    • 2011
  • To screen several promising red pepper cultivars, may be adaptable to organic cultivation conditions, seventy six F1 hybrids commercial and eight local purebred red pepper cultivars were tested. Comparing the infection rate of phytophthora blight between commercial (F1 hybrid) and local (Purebred) cultivars, average infection rate of commercial cultivars was 9.8% and that of local cultivars was 17.8%. But the infected fruits rate of anthracnose in field were similar as 3.3% in commercial (F1 hybrid) and 3.1% in local (Purebred) cultivars. In yield characteristics, average yield of commercial cultivars was 2.89 t $ha^{-1}$ and that of local cultivars was 2.22 t $ha^{-1}$. For organic pepper farmers it is more favourable to cultivation purebred cultivars because they can save to the same quality plant next year's crop. In this study among the local purebred cultivars, two cultivars are promising that their yield near to 3 t $ha^{-1}$ and have disease field resistance.

활성탄소계 섬유포 전극을 이용한 전기이중층 커패시터용 유기 전해액의 제조 (Fabrication of Organic Electrolytes for Electric Double Layer Capacitor with Activated Carbon Cloth Electrode)

  • 강안수
    • 대한안전경영과학회지
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    • 제2권2호
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    • pp.95-108
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    • 2000
  • Electrochemical charateristics of activated carbon fiber cloth(ACFC) electrode were studied with propylene carbonate(PC), ${\gamma}$-butyrolactone(GBL) and N,N-dimethyl-formamide(DMF) as a solvent and tetraethylammoniumtetrafluoroborate(TEABF$_4$), tetraethylammoniumhexafluorophosphate(TEABF$_{6}$), tetrabutylammoniumtetrafluoroborate(TBABF$_4$) and tetrabutylammonium hexafluorophosphate(TBAPF$_6$) as an electrolytes(active material). The concentrations of electrolytes were in the range of 0.2~1.2 N, the volume ratios of PC and DMF as a mixed solvent system, were 90:10, 80:20, 70:30, 60:40, 50:50, and 40:60 vol%. Electrochemical characteristics such as electric conductivity, internal resistance, and electric capacitance of fabricated unit cells were measured after the moisture of activated material was removed with molecular sieve. Electrochemical characteristics were better in mixed solvents system than in mono solvent system. The mono solvent system of 1.0 N electrolyte of GBL/TEABF$_4$ with activated carbon cloth electrodes showed better result but the mixed solvent system with PC and DMF/TEABF$_4$(50:50 vol%) and the concentration of 1.0 N electrolyte showed the best characteristics. Internal resistance was 3.47 $\Omega$ and specific capacitance was 19.1 F/g respectively.y.

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REQUIREMENTS FOR AUTOMATED CODE CHECKING FOR FIRE RESISTANCE AND EGRESS RULE USING BIM

  • Jiyong Jeong;Ghang Lee
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.316-322
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    • 2009
  • The more repetitive, complex and objective the work, the more effective automation is. Code checking is an example of this. Checking building codes through a thick set of drawings is error-prone and time-consuming. In order to overcome this problem, several organizations have initiated efforts to automate building-code checking. Initiated study mainly focused on checking codes for invalidation, required size and crash, and then area of checkable codes have been expanding. But, it has not been considered for codes regarding anti-disaster/egress, which is also issued these days. This study is about how to automatically check codes for anti-disaster and egress based on Korea building codes. The codes can be categorized as five sections: egress way, material/capability, principals of evacuation, evacuation stairway and fire protection partition. To check automatically, there are problems, such as expression of codes for egress and limitation of extractable information from the BIM model. This paper shows what problems exist and assignments to be resolved. Also, current developing processes are presented, and suggestions are made about the direction for the work that remains.

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Combination of oxaliplatin and β-carotene suppresses colorectal cancer by regulating cell cycle, apoptosis, and cancer stemness in vitro

  • Junghyeun Lee;Seung Chul Heo;Yuri Kim
    • Nutrition Research and Practice
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    • 제18권1호
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    • pp.62-77
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    • 2024
  • BACKGROUND/OBJECTIVES: Colorectal cancer (CRC) is the third most common cancer worldwide with a high recurrence rate. Oxaliplatin (OXA) resistance is one of the major reasons hindering CRC therapy. β-Carotene (BC) is a provitamin A and is known to have antioxidant and anticancer effects. However, the combined effect of OXA and BC has not been investigated. Therefore, this study investigated the anticancer effects and mechanism of the combination of OXA and BC on CRC. MATERIALS/METHODS: In the present study, the effects of the combination of OXA and BC on cell viability, cell cycle arrest, and cancer stemness were investigated using HCT116, HT29, OXA-resistant cells, and human CRC organoids. RESULTS: The combination of OXA and BC enhanced apoptosis, G2/M phase cell cycle arrest, and inhibited cancer cell survival in human CRC resistant cells and CRC organoids without toxicity in normal organoids. Cancer stem cell marker expression and self-replicating capacity were suppressed by combined treatment with OXA and BC. Moreover, this combined treatment upregulated apoptosis and the stem cell-related JAK/STAT signaling pathway. CONCLUSIONS: Our results suggest a novel potential role of BC in reducing resistance to OXA, thereby enhances the anticancer effects of OXA. This enhancement is achieved through the regulation of cell cycle, apoptosis, and stemness in CRC.

근감소성 비만에 대하여 근육량을 보존할 수 있는 체중 감량 중재에 대한 고찰 (Review on Weight Loss Interventions that Can Prevent Muscle Mass Loss in Sarcopenic Obesity)

  • 박민정;임영우;김은주
    • 대한한의학회지
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    • 제45권1호
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    • pp.80-99
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    • 2024
  • Objectives: The objective of this study was to review clinical studies conducted over the last ten years that investigated weight or fat loss interventions that can preserve muscle or fat-free mass in Sarcopenic obesity Methods: PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), Research Information Sharing Service (RISS) and Korea Studies Information Service (KISS) were searched for Randomized clinical trials that had investigated all-type of interventions on the management of sarcopenic obesity from October 2013 to September 2023. Results: A total of 14 studies met all the inclusion criteria. Interventions that increase muscle mass while reducing body fat at the same time included resistance training (including using elastic bands) and whole-body electromyostimulation(WB-EMS) in exercise intervention and Hypocaloric high-protein diet in nutritional intervention, exercise and nutritional combined intervention, and combination intervention of electrical acupuncture and amino acid supplementation. Among them, the most positive method of changing the body composition in sarcopenic obesity was the electric acupuncture and amino acid supplements. Conclusion: Varying diagnostic criteria and management interventions for sarcopenic obesity in the included studies made it hard to maintain homogeneity across the studies. Well-defined criteria for diagnostic sarcopenic obesity should be considered. In addition, since all of the interventions examined did not show sufficient clinical effectiveness, follow-up studies are needed to confirm effective interventions for sarcopenic obesity patients in the future.

우리나라 생강 뿌리썩음병의 연구현황과 향후과제 (Review of Researches on Rhizome Rot of Ginger and Future Tasks for Its Management in Korea)

  • 김충회
    • 식물병연구
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    • 제10권2호
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    • pp.87-93
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    • 2004
  • Rhizome rot of ginger, caused by Pythium myriotylum, a major limiting factor for its production, has occurred annually, but become severe, especially in hot and humid years with frequent rainfalls in Korea. Most studies on rhizome rot have been carried out since 1980s in the National Institute of Agricultural Sciences and Technology, Honam Crop Experimental Station and Choongnam Provincial Rural Development Administration. Many aspects of rhizome rot, such as survey of the disease incidence, taxonomy, pathogenicity and physiology of pathogen, and ecology of soilborne inocula have been studied in the researches. However, intensive studies have been concentrated on management technologies of the disease including seed-rhizome disinfection, soil sterilization, evaluation of cultivar resistance, and fungicide application, and most developed technologies have been used in commercial farmings. In future, development of resistant varieties and simple soil disinfection technologies applicable in Korean condition and economically feasible fungicide application technology have to be developed for better management.

Business Process Reengineering of an Information Exchange Management System for a Nationwide Cyber Threat Intelligence

  • Pramadi, Yogha Restu;Rosmansyah, Yousep;Kim, Myonghee;Park, Man-Gon
    • 한국멀티미디어학회논문지
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    • 제20권2호
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    • pp.279-288
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    • 2017
  • Nowadays, nations cyber security capabilities play an important role in a nation's defense. Security-critical infrastructures such as national defenses, public services, and financial services are now exposed to Advanced Persistent Threats (APT) and their resistance to such attacks effects the nations stability. Currently Cyber Threat Intelligence (CTI) is widely used by organizations to mitigate and deter APT for its ability to proactively protect their assets by using evidence-based knowledge. The evidence-based knowledge information can be exchanged among organizations and used by the receiving party to strengthen their cyber security management. This paper will discuss on the business process reengineering of the CTI information exchange management for a nationwide scaled control and governance by the government to better protect their national information security assets.

개인과 법인사업자 간 부가가치세 인식차이 분석 (The Study On The Differences of Recognition Between Self-management and Cooperative, and the Improvement About Value Added Tax)

  • 심준섭;정용태
    • 벤처창업연구
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    • 제1권2호
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    • pp.135-155
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    • 2006
  • 본 연구는 현행 부가가치세제에 대한 개인사업자와 법인사업자간의 인식의 차이를 설문 조사하여 분석하는데 있다. 조사결과를 요약하면 다음과 같다. 첫째, 현행 부가가치세법상 세율이 높은 것으로 인식하고 있는 것으로 나타났다. 그러나 개인과 법인기업체 간의 인식차이는 보이지 않았다. 둘째, 부가가치세의 정확한 신고시 경영에 미칠 영향에 관해 개인은 영향이 어느 정도 있는 것으로 인식한 반면, 법인의 경우 대체로 영향이 없는 것으로 인식하여 차이를 보였다. 셋째, 현행 세금계산서 작성 및 교부시기의 경직성에 대해 대체로 현행 세금계산서 작성 및 교부시기의 경직성이 어느 정도 있는 것으로 나타났으며, 개인과 법인기업체 간의 의미 있는 인식차이는 보이지 않았다. 넷째, 간이과세자의 매입세금계산서 등에 대해 개인의 경우 간이과세자의 매입세금계산서 등에 대한 세액공제 유지가 대체로 바람직한 것으로 인식한 반면, 법인의 경우 보통정도로 인식하고 있는 것으로 나타났다.

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가스터빈 패키지 내충격 성능평가에 관한 연구 (Evaluation of the Shock Resistance of a Gas Turbine Package)

  • 김재부;박윤기;박민석;이종환;안성찬
    • 대한기계학회논문집A
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    • 제41권10호
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    • pp.1005-1009
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    • 2017
  • 본 연구에서는 수중폭발에 의한 가스터빈 패키지에 작용하는 충격하중을 평가하고, 충격하중에 대한 가스터빈 패키지의 내충격 안전성을 검토하였다. 이를 위해 먼저 BV043에 따른 시간이력 충격하중을 산출하고, 산출된 충격하중을 바탕으로 이상화된 WEM(Whole Engine Model, 전체시스템)에 대한 시간영역에서의 과도응답해석을 수행하였다. 이를 통해 가스터빈 패키지의 주요구성품에 전달되는 하중을 평가하였으며, 평가된 전달하중을 바탕으로 주요구성품의 상세모델에 대한 내충격 안전성 검토를 수행하였다. 검토결과 가스터빈 패키지는 기준응력 대비 최소 1.0 이상의 안전율을 가지는 것을 확인하였다. 그리고 실물테스트를 통해 가스터빈 패키지 엔진제어시스템(EMS : Engine Management System) 구조 및 제어기능의 내충격 건전성을 검증하였다.