• 제목/요약/키워드: analysis and design

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A Study on the Effect of Pro-Environmental Consumers on Environmental Education Utilizing Value-Attitude-Behavior Model (가치-태도-행동모델(VAB)을 활용한 친환경 소비자의 환경교육의 조절효과 연구)

  • Hwang, Youn-Sung;Seo, Yong-Mo
    • Journal of the Korea Convergence Society
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    • v.8 no.7
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    • pp.273-282
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    • 2017
  • This empirical study is to verify the moderating effects of environmental education on pro-environmental consumers. For this purpose, we used Value-Attitude-Behaviro Model(VAB). In addition, as an environmental education method, the environmental education method using 7 environmental movies by the multimedia with excellent learning effect in order to increase the interest and educational commitment of the learners was utilized. A total of 116 subjects were divided into experimental group and control group, and the experiment was designed based on Pretest-Posttest Control Group Design to grasp the effect of environmental education after conducting environmental education to the experiment group. The results of the analysis showed that environmental education had no effect on environmental values but it had a positive effect on improving the attitude and the pro-environmental behavior. This study proved that the sustainable environmental education could form pro-environmental behavior, even though the environmental sense of values had not been formed in adolescence, and furthermore, the earlier researches had been mainly focused on the effect of the environmental education for the adolescent.

Analysis of Oxygen Combustion Characteristics of a Low Grade Coal Using IEA-CFBC Model (IEA-CFBC 모델을 이용한 저급탄의 순산소 연소 특성 분석)

  • Gwak, You Ra;Kim, Ye Bin;Keel, Sang In;Yun, Jin Han;Lee, See Hoon
    • Korean Chemical Engineering Research
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    • v.56 no.5
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    • pp.631-640
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    • 2018
  • The application of an oxy-combustion circulating fluidized bed combustor (Oxy-CFBC) for low grade coals has recently developed in the world to meet the continuous increase of energy demand and to achieve the reduction of greenhouse gases. Since demo plants for Oxy-CFBC have been developed, the combustion properties of Oxy-CFBC in various operation conditions, such as gas flow rates, combustion temperature, fuel, and so on, should be investigated to develop design criteria for a commercial Oxy-CFBC. In this study, a computational simulation tool for Oxy-CFBC was developed on the basis of the IEA-CFBC (International Energy Agency Circulating Fluidized Bed Combustor) model. Simulation was performed under various conditions such as reaction temperature ($800^{\circ}C{\sim}900^{\circ}C$), oxygen contents (21%~41%), coal feeding rate, Ca/S mole ratio (1.5~4.0), and so on. Simulation results show that the combustion furnace temperature is higher in oxy 1 than air fired. However, the temperature gradient tended to decrease with increasing oxy mixing percent. In case of $SO_x$, the higher the Ca/S mole ratio and oxy mixing percent, the higher the desulfurization efficiency.

Development of numerical model for estimating thermal environment of underground power conduit considering characteristics of backfill materials (되메움재 특성을 고려한 전력구 열환경 변화 예측 수치해석모델 개발)

  • Kim, Gyeonghun;Park, Sangwoo;Kim, Min-Ju;Lee, Dae-Soo;Choi, Hangseok
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.19 no.2
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    • pp.121-141
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    • 2017
  • The thermal analysis of an underground power conduit for electrical cables is essential to determine their current capacity with an increasing number of demands for high-voltage underground cables. The temperature rises around a buried cable, caused by excessive heat dissipation, may increase considerably the thermal resistance of the cables, leading to the danger of "thermal runaway" or damaging to insulators. It is a key design factor to develop the mechanism on thermal behavior of backfilling materials for underground power conduits. With a full-scale field test, a numerical model was developed to estimate the temperature change as well as the thermal resistance existing between an underground power conduit and backfill materials. In comparison with the field test, the numerical model for analyzing thermal behavior depending on density, moisture content and soil constituents is verified by the one-year-long field measurement.

Performance Characteristics of Organic Rankine Cycle Using Medium Temperature Waste Heat with Different Working Fluids (중온 배기열을 이용한 유기랭킨사이클 작동유체별 성능특성)

  • Kwon, Dong-Uk;Heo, Ki-Moo;Yoon, Sung-Hoon;Moon, Yoon-Jae;Yoo, Ho-Sun;Lee, Jae-Heon
    • Plant Journal
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    • v.10 no.2
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    • pp.38-47
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    • 2014
  • Renewable Portfolio Standards was introduced into the system in Korea in 2012. Interest in the unutilized and renewable energy sources is increasing. and these being actively investigated. An organic rankine cycle has emerged as an alternative in order to take advantage of bio-gas engine heat of sewage treatment plants whose capacity is 1500 kW. The organic rankine cycle power system was simulated by a simulator which is a commercial program of power plant design and performance analysis. The biogas engine is operated by $460^{\circ}C$ and 2.7 kg/s flow rate in the sewage treatment plant. Working fluids(R-601a, R-123, R-245fa) are selected to use in ORC power system in this temperature range. It was the isopentane that is the best performance among three working fluids. It could be obtained net power of 163.1 kW and efficiency of 13.66% from isopentane in the simulation.

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Analysis on Entry and Exit Behaviors at the Weaving Section of a Continuous Auxiliary Lane: Focused on Clover-shaped Interchanges (연속 부가차로 엇갈림 구간 진출입 행태분석에 관한 연구: 클로버형 입체교차로를 중심으로)

  • Park, Je-Jin;Ha, Tae-Jun;Oh, Jae-Chul;Choi, Heung-Seob
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.16 no.6
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    • pp.79-89
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    • 2017
  • Current intersection with collectors allow entry and exit in the relevant sections just as defined by the pertinent design criteria without considering driving behavior of the vehicles coming in and out of the intersection. This study analyzed the roads in the weaving sections to review driving behavior. As a result, vehicles entering a main line are found to try to change a driving lane at a section 50~55m away from a nose part, while those entering a ramp from a main line try to change it at 35~40m from a nose part. Accordingly vehicles exiting to a connecting road from a main line were found to take prior action to change a lane earlier than those entering a main line. Conflict took place intensively at 35~40m section from the nose part entering a main line. Consequently, such conflict at an weaving section may be controlled by adjusting the length of driving lane making use of a double line (solid and dotted line) that can control changing a lane. Outcome of this study may be used as a basic data for operating and maintaining an weaving section of a intersection of a road and improving traffic safety.

Compensation Committee Quality and Managers' Pay-Performance Sensitivity (보상위원회의 품질과 성과-보상민감도)

  • Choi, Won-Ju
    • Management & Information Systems Review
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    • v.35 no.1
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    • pp.173-188
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    • 2016
  • The introduction and operation of compensation committee can affect managers' incentive-compensation system. In this context, The purpose of this paper examines whether managers' pay-performance sensitivity is affected by the quality of the compensation committee(compensation committee size, the proportion of outside directors on the compensation committee, the proportion of directors with 2 or more non additional board seats on the compensation committee) To test this hypothesis, we use a sample of 260 firm-year observations between 2001-2013. The results are as follows. Firstly, we find that no significant relevance between the compensation committee size and pay-performance sensitivity. But the proportion of outside directors on the compensation committee and the proportion of directors with 2 or more non additional board seats on the compensation committee is positively associated with both pay-earnings based performance sensitivity and pay-stock based performance sensitivity. Secondly, we find that the integration quality of the compensation committee is positively associated with both pay-earnings based performance sensitivity and pay-stock based performance sensitivity. Overall, our analysis suggests that compensation committee are important mechanism in the design of efficient incentive-compensation system.

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An Analysis of the Locational Motives for the Korean Auto Industry′s Investment in the U.S. - Case Study of Hyundai Motor Manufacturing Alabama - (우리나라 자동차산업의 미국투자 입지동기 분석 - 현대자동차 미 앨라배마 투자 사례를 중심으로 -)

  • 서정욱
    • Journal of the Economic Geographical Society of Korea
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    • v.7 no.1
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    • pp.65-81
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    • 2004
  • Foreign direct investment (FDI) by firms has various motives in terms of the strategy for firms' long-term growth. This research uses the case study of Hyundai Motor Manufacturing Alabama to analyze the motives of the Korean auto industry's FDI in the U.S. and the locational factors that determined the selection of the site. This paper starts from the question of why Hyundai made the decision to invest in the U.S., which is not favorable in terms of production cost, especially considering that its exports to the U.S. have been on the increase. The results indicate that the strongest motive for the decision to invest in the U.S. was to ameliorate the trade friction between Korea and the U.S. Given that Hyundai depends on the U.S. market to a large extent for its exports, the foremost motive was to use local production in order to reduce the serious trade imbalance in the automobile sector between Korea and the U.S. in order that trade friction with the U.S. may be avoided and causes for trade disputes may be reduced. Other motives such as improving the access to local consumers were of secondary importance. After the selection of the country in which to invest, however, various factors were considered in the decision regarding the location of the plant, and incentives by local governments ultimately played a key role in this decision. The results imply that the Korean manufacturing industry's investment in the U.S. cannot be explained by traditional FDI theories and instead was greatly driven by a strategic defensive motive. In addition, the results confirm that the design of an appropriate incentive structure by host governments is important for attracting FDI.

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A Experimental Analysis on the Relationship between the Angle of a Locker and the Clamping Force of Wedge Type Rail Clamp (Locker의 물림각과 쐐기형 레일클램프의 압착력에 관한 실험적 고찰)

  • Han Dong-Seop;Shim Jae- Joon;Han Geun- Jo;Lee Kwon-Hee
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2005.10a
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    • pp.247-252
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    • 2005
  • The wedge type rail clamp has the operating mechanism: First, the jaw pad clamps a rail with small clamping force Next as the wind speed increases, the clamping force of the jaw pad is increased by the wedge. In order to design the wedge type rail clamp, we need to determine the proper wedge angle to minimize the sliding distance of a roller and the proper clamping angle of a locker to generate the initial clamping force of a jaw pad. The researches for the proper wedge angle have conducted, and in this study we conducted the investigation to determine the proper clamping angle of a locker in the rail clamp with wedge angle of $10^{\circ}$. Because the initial damping force of the jaw pad was determined by the clamping angle of the locker, in order to carry out the clamping force of a jaw pad, we measured the locking force applied to a locker with respect to the clamping angle of a locker, such as $3^{\circ},\;4^{\circ},\;5^{\circ},\;6^{\circ},\;$ using a pressure gauge, and compared the results with the FEA results.

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The evaluation of image guide system in case of rectal cancer (직장암 치료시 영상유도 시스템의 유용성 평가)

  • Jang, Sewuk;Ahn, Seungkwon;Lee, Sangkyoo;Kim, Jooho;Lee, Wonju;Cho, Jeonghee
    • The Journal of Korean Society for Radiation Therapy
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    • v.29 no.1
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    • pp.85-92
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    • 2017
  • purpose: Image Guide System offers therapy precise, especially Intensity Modulated Radiation Therapy. However, organs at pelvis have variation and uncertainties each therapy. it brings IG system for verifying patient's position. In this study, analysis the variation at pelvis during rectal cancer radiation therapy. Moreover design the patient re-setup technique and apply to patients. Material and Method: 40 rectal cancer patient who have radiation therapy. The 530 image which acquired from IG system are analyzed. The bone structure, bladder, gas in the rectum, small bowel, soft tissue, weigh loss are evaluated by the criterion. The criterion are classified by best, good, bad and figure out the ratio with count. The re-setup proceed in case of one or over the two get the bad criterion and figure out the ratio of re-setup results: The ideal of therapy ratio is 19.2 % each criterion. And the good for therapy ratio is 54.9 %, the cases of bad for therapy is 25.8 %. The bad cases are have therapy after re-setup with post process. conclusion: Each pre-treatment image that acquired IG system has different results despite of same patients. The 25.8 % need to re-setup in order to unsuitable therapy. It is implies that the IG system is necessary establishing precise treatment plan like IMRT especially rectal cancer.

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XML Schema Evolution Approach Assuring the Automatic Propagation to XML Documents (XML 문서에 자동 전파하는 XML 스키마 변경 접근법)

  • Ra, Young-Gook
    • The KIPS Transactions:PartD
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    • v.13D no.5 s.108
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    • pp.641-650
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    • 2006
  • XML has the characteristics of self-describing and uses DTD or XML schema in order to constraint its structure. Even though the XML schema is only at the stage of recommendation yet, it will be prevalently used because DTD is not itself XML and has the limitation on the expression power. The structure defined by the XML schema as well as the data of the XML documents can vary due to complex reasons. Those reasons are errors in the XML schema design, new requirements due to new applications, etc. Thus, we propose XML schema evolution operators that are extracted from the analysis of the XML schema updates. These schema evolution operators enable the XML schema updates that would have been impossible without supporting tools if there are a large number of XML documents complying the U schema. In addition, these operators includes the function of automatically finding the update place in the XML documents which are registered to the XSE system, and maintaining the XML documents valid to the XML schema rather than merely well-formed. This paper is the first attempt to update XML schemas of the XML documents and provides the comprehensive set of schema updating operations. Our work is necessary for the XML application development and maintenance in that it helps to update the structure of the XML documents as well as the data in the easy and precise manner.