• 제목/요약/키워드: technical change

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종합열차운행제어의 병행 운전(교체) 방안에 관한 고찰 (A Study on the Parallel Control(Change) at the Total Traffic Control)

  • 김정수;이재남;이기승;안현준
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.675-682
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    • 2006
  • The command of Subway is intended to adjust and control the train operation, and to play a key role of the total passenger transport and all kinds of affairs related to the safe train operation. Also, this can be considered as affairs to be controlled and operated by Total Traffic Control. For the purpose of developing the ATO system in using the new control technology by substituting the conventional ATS equipment, this technical document includes the technical points resulted from doing the replacement construction in the entire section of Subway Line 2 by Seoul Metro. The replacement work with the new ATO System should neither stop nor affect the system under operation while operating the current ATS System. The different systems should not interfere with each other while performing their individual affairs, and be composed to share the important data for the parallel operation. This technology is needed to proceed in assurance of a high degree of reliability.

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친환경주거의 계획 및 기술요소에 대한 한.일 사례비교 (A Case Study on Planning Factors and Technical Elements of the Environment-Friendly Apartment Complex in Korea and Japan)

  • 정유선;신수영;유복희;남규현;윤정숙
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2002년도 추계학술발표대회
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    • pp.215-221
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    • 2002
  • The purpose of this study is to accumulate basic data to establish planning direction and planning factors for the environment-friendly apartment complex by clarifying general concept and mark of it. For this purpose, the field study has been conducted to the environment-friendly apartment complex in Korea and Japan. The major findings of this study are as follows; 1) The basic concept of planning factors for environment-friendly apartment complex are natural harmony, improvement of residents' health & amenity, energy & resources saving and response to the social change. 2) For Japan, the planning factors and technical elements for the environment-friendly apartment complex were applied in the whole range of apartment complex with various and positive methods. For Korea, on the other hand, application of the planning factors of energy saving, resources saving and minimizing environment pollution was insufficient.

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지방의료원의 효율성에 대한 정태적 및 동태적 분석 (Static and Dynamic Analysis of Efficiency of Korean Regional Public Hospitals)

  • 김종기;전진환
    • 한국병원경영학회지
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    • 제15권1호
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    • pp.27-48
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    • 2010
  • The purpose of this paper is to analyze the efficiency change and its determinants of the regional public hospitals. We utilize 34 regional public hospital's panel data for 6 years from 2003 to 2008. We use DEA(Data Envelopment Analysis)-CCR, BCC model, DEA/Window model, and DEA Profiling. The empirical results show the following findings. First, technical efficiency shows that approximately 3.6% of inefficiency exists on the regional public hospitals and it reveals that the cause for technical inefficiency is due to scale inefficiency. Second, DEA/Window results show that the stable dissimilarity by standard deviation, LDP of CCR. Third, the results of partial efficiency by DEA Profiling show that increase efficiency depends on the number of beds, doctors, and nurses.

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Effect of Fluorescent Whitening Agent and Tinting Dye on Optical Properties of Paper

  • Wang Li-Jun;Yoon Byung-Ho
    • 펄프종이기술
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    • 제37권5호통권113호
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    • pp.8-14
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    • 2005
  • The difference of whiteness, brightness and lightness was clearly explained in this paper by use of a tinting dye and a fluorescent whitening agent which are commercially widely used to make paper look whiter. Other optical properties such as tint, color shade, and color difference were also discussed. It is concluded that in comparing two tinting dyes, lightness (L*) is the most important property to be compared, while whiteness data should be used in caution in order not to surpass its significant range, and a*, b* values can also be used to find the change of color shades together with ${\Delta}E$ as color difference. In comparing two fluorescent whitening agents, whiteness or brightness values are most important to be compared, but lightness values are not suitable for this purpose; a*, b* and color difference ${\Delta}E$ can also be referred, but with less significance.

목질계 Biomass의 변환이용(제1보)-기계펄프로부터 용해용펄프의 제조- (Conversion of Woody Biomass for Utilization( I )-The Preparation of Dissolving Pulp from Mechanical Pulp-)

  • 양재경;임부국;이종윤
    • 펄프종이기술
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    • 제29권3호
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    • pp.51-59
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    • 1997
  • Dissolving pulp is a low yield(30∼35%) bleached chemical pulp that has a high cellulose content (95% or higher) suitable for use in cellulose derivatives such as rayon, cellulose acetate. This research was studied for dissolving pulp preparation as the raw material of viscose rayon from commertial pulps. (TMP, CP, DIP) In the change of pulp(cellulose) characteristics after sodium hypochlorite and solvolysis treatment. the following results were obtained In the case of sodium hypochlorite pretreatment, we have obtained pulp that high purity cellulose, but degree of polymerization was inclined to decrease less than 170∼240. Comparing sodium hypochlorite pretreatment and solvolysis pretreatment, solvolysis pretreatment is superior to sodium hypochlorite process for making dissolving pulp. We think that the low degree of polymerization of cellulose because of increasing degradation of cellulose during delignification treatment.

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White ledger의 오존 탈묵 기구 (Ozone Deinking Mechanism of White Ledger)

  • 원종명;노국일
    • 펄프종이기술
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    • 제33권3호
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    • pp.24-28
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    • 2001
  • The utilization of wastepaper as a papermaking raw material is everlastingly required for the environmental protection of earth. However the recycling of wastepaper for this purpose cause another problem such as the increasing of the load of wastewater treatment, lower strength properties of paper, and poor printability, etc. The interest in the development of the environmentally friendly deinking technology is increased continuously. Thus, our research team have tried to apply the ozone to the deinking of white ledger and ONP, and obtained the positive results which can be considered as an alternative method for the conventional deinking method. The purpose of this study is to investigate the mechanism of ozone deinking. Styrene acrylate and polystyrene were treated with ozone and measured the change of molecular weight with the GPC. The molecular weight distribution obtained with GPC showed only slight increase by the ozone treatment, and gel formation by the polymerization was observed. Therefore the removal of ink particles with ozone treatment seems to be facilitated by the increase of the brittleness and decrease of adhesive property.

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국내 바이오에너지 보급에 따른 온실가스 저감 평가 (Reduction of Green House Gases by Bioenergy Supplying in Korea)

  • 홍연기
    • 융복합기술연구소 논문집
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    • 제4권1호
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    • pp.15-20
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    • 2014
  • Recently, the development of renewable energy sources in Korea has been needed due to climate change. One of powerful alternative energy resources to mitigate emission is to switch conventional fuels to renewable energy, such as bioenergy. In this study, current status of bioenergy conversion technology and its supply in Korea was investigate. Based on theoretical, technical and realizable potential of biomass in Korea, the amount of reduction of green house gases was estimated. The results shown that the contribution of biomass on 2020 reduction target of green house gases emission in power generation was $513,000\;tCO_2/yr$ and utilization ratio of technical potential of biomass was 6.4%. For the effective supply of bioenergy in Korea, more exact estimation of realizable potential of biomass in Korea and stable supply sources are needed.

Post-buckling analysis of Timoshenko beams made of functionally graded material under thermal loading

  • Kocaturk, Turgut;Akbas, Seref Doguscan
    • Structural Engineering and Mechanics
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    • 제41권6호
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    • pp.775-789
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    • 2012
  • This paper focuses on post-buckling analysis of functionally graded Timoshenko beam subjected to thermal loading by using the total Lagrangian Timoshenko beam element approximation. Material properties of the beam change in the thickness direction according to a power-law function. The beam is clamped at both ends. The considered highly non-linear problem is solved by using incremental displacement-based finite element method in conjunction with Newton-Raphson iteration method. As far as the authors know, there is no study on the post-buckling analysis of functionally graded Timoshenko beams under thermal loading considering full geometric non-linearity investigated by using finite element method. The convergence studies are made and the obtained results are compared with the published results. In the study, with the effects of material gradient property and thermal load, the relationships between deflections, end constraint forces, thermal buckling configuration and stress distributions through the thickness of the beams are illustrated in detail in post-buckling case.

경쟁력 있는 리모델링 공사에 대한 기술적 요소 (Technical Elements for a Competitive Remodeling Construction)

  • 전의연;김규용
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 봄 학술논문 발표대회
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    • pp.157-158
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    • 2023
  • Building Information Modeling (BIM) design has been mandatory in Korea since 2016, and it has been gradually expanding in the industry, with a slow attempt to apply it in remodeling constructions. This is because Korea is facing a situation where many buildings are over 30 years old and require remodeling or reconstruction. The remodeling industry is also a growing market, as it saves construction time and cost compared to reconstruction. BIM is an ideal technology element for a competitive remodeling construction, as remodeling constructions face a complicated construction process from the start, including demolition, maintenance, and reinforcement to save the change process. However, there are still limitations in applying BIM to remodeling constructions, due to considerations of the existing building and the complicated requests of the inhabitants. BIM still has technical and environmental limitations for general use. In this study, I analyzed BIM application cases from existing studies and suggest what improvement points should be strengthened.

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방글라데시 해안지대 기후변화에 따른 영세 어업인 생계 위험 경감 방안 (Livelihood Risk Reduction for Artisanal Fisheries Communities due to Climate Change in Coastal Area of Bangladesh)

  • 강경미
    • 한국수산과학회지
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    • 제56권3호
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    • pp.341-346
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    • 2023
  • This study aimed to suggest an alternative income generation (AIG) for local artisanal fisheries communities in the southern coastal area of Bangladesh, which is vulnerable to climate change. To analyze the problems of local artisanal fisheries caused by climate change, field surveys and in-depth interviews with fishermen and government officials were conducted. Livelihood risk factor (LRF) in the marine fishing sector included reduction of fishing days and fish production and damage to fishing vessels and fishing gear due to cyclone and sea-level rise. LRF in the aquaculture sector included cultured fish escape, reduction of aquaculture production, and water pollution due to Monsoon flood. A common challenge for two sectors was high interest rate on commercial loans. Small-scale tank aquaculture is recommended as AIG for securing income of artisanal fisheries communities. In the early stages of dissemination of small-scale tank aquaculture technology, it is necessary to prevent fishermen from struggling to repay high-interest rate loans through technology transfer and facility support by official development assistance. The aquaculture training center, along with the technical education, will also contribute toward expansion of local distribution network and marketing support to establish a value chain for local artisanal fisheries communities.