• Title/Summary/Keyword: resistance management

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A Study on the Electrical Properties of Ethylene Propylene Rubber by Thermal Treatment and Irradiation (방사선 및 열처리에 의한 에틸렌프로필렌 고무의 전기적 특성에 관한 연구)

  • 이성일
    • Journal of the Korea Safety Management & Science
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    • v.4 no.4
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    • pp.137-146
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    • 2002
  • In order to investigate the effect of irradiation by $^{60}Co-\gamma$rays as well as the e thermal treatment on the dielectric deterioration in ethylene propylene rubber, insulating material for electric cables used in atomic power plants, charging discharging current, residual built- up voltage and dielectric properties are measu discussed in this study. Variance in the characteristic of relative dielectric constant as a function of tem was observed in relatively high dose of irradiation. Since glass transition tem appeared at tens of degree Celsius below zero, the characteristic is attributed orientation polarization. Dielectric loss is generally increased, with increasing d irradiation in the characteristic of dielectric loss as a function of temperature, No d loss by thermal treatment was observed. Dielectric resistance decreases with increa of irradiation in the characteristic of charging current as a function of temperature be considered that dielectric resistance seems to be recovered by thermal treatm characteristic of discharging current as a function of time in the specimen less ir become similar to that of the unirradiated, when thermal treated. A peak is shown residual built- up voltage as a function of time, and the corresponding time of the shorten as increasing dose of irradiation. It is also observed that the corresponding the peak is lengthened by thermal treatment.

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

  • Lim, Nam-Yun;Park, Gu-Gon;Park, Jin-Soo;Yoon, Young-Gi;Lee, Won-Yong;Lim, Tae-Won;Kim, Chang-Soo
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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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.
    • Korean Journal of Organic Agriculture
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    • v.19 no.spc
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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.

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

  • 강안수
    • Journal of the Korea Safety Management & Science
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    • v.2 no.2
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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
    • International conference on construction engineering and project management
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    • 2009.05a
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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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    • v.18 no.1
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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.

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

  • Min-jeong Park;Young-Woo Lim;Eunjoo Kim
    • The Journal of Korean Medicine
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    • v.45 no.1
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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.

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

  • Kim, Choong-Hoe
    • Research in Plant Disease
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    • v.10 no.2
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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
    • Journal of Korea Multimedia Society
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    • v.20 no.2
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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.

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

  • Shim, Joon-Sup;Jung, Yong-Tae
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.1 no.2
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    • pp.135-155
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    • 2006
  • The purpose of this paper IS to examine the differences of cognition between self-management and corporation in report and payment of Value Added Tax. And then We want to suggest the policy of improvements to reduce the resistance of tax-payer in V.A.T. Data was collected for 250 firms' samples from the self-employed and corporation in Daegu Seongseo Industry District. The main results of empirical study are as follows. First, Value Added Tax is not fair in all companies. But It couldn't find the differences between self-employed a d corporation in statistical meaning. Second, It was found the cooperatives generally think to pay the taxes in rule, but self-employed not do it in the report and payment of Value Added Tax. But we couldn't find the important differences between self-employed and corporation in statistical meaning. We propose to improve the polices of introduction of tax rates of multiples in the charging and to redesign the definition of a tax-payer of value added tax to reduce the resistance in report and payment.

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