• 터널과지하공간
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• 제4권1호
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• pp.24-30
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• 1994

Although a dry-system tunnel is not good for reasons fo economy and construction, it has been applied to some tunnels under construction owing to the advantages of good long-term maintenance of tunnel, prevention of consolidation settlement due to the drawdown of groundwater, preservation of the ecosystem, cutailment of operation cost, and so on. The stability of groundwater and the change of the applied water pressure after water proofing were analysed by the finite element method. Using this result, an example of designing the secondary lining for the dry-system tunnel which is to be constructed in low-permeability hard rock was presented.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.426-428
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• 2003

Optical and microwave remote sensing data have been widely used in land cover and land use classification. Thanks to the spectral absorption characteristics of ground object in visible and near infrared region, optical data enables to extract different land cover types according to their material composition like water body, vegetation cover or bare land. On the other hand, microwave sensor receives backscatter radiance which contains information on surface roughness, object density and their 3-D structure that are very important complementary information to interpret land use and land cover. Separate use of these data have brought many successful results in practice. However, the accuracy of the land use / land cover established by this methodology still has some problems. One of the way to improve accuracy of the land use / land cover classification is just combination of both optical and microwave data in analysis. In this paper for the research, the author used LANDSAT TM scene 127/45 acquired on October 21, 1992, JERS-1 SAR scene 119/265 acquired on October 27, 1992 and aerial photographs taken on October 21, 1992. The study area has been selected in Hanoi City and surrounding area, Vietnam. This is a flat agricultural area with various land use types as water rice, secondary crops like maize, cassava, vegetables cultivation as cucumber, tomato etc. mixed with human settlement and some manufacture facilities as brick and ceramic factories. The use of only optical or microwave data could result in misclassification among some land use features as settlement and vegetables cultivation using frame stages. By combination of multitemporal JERS-1 SAR and TM data these errors have been eliminated so that accuracy of the final land use / land cover map has been improved. The paper describes a methodology for data combination and presents results achieved by the proposed approach.

• 전기학회논문지
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• 제60권6호
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• pp.1274-1279
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• 2011

The purpose of this paper is to present the manufacturing defect and damage pattern of a 3 phase 22.9/3.3kV oil immersed transformer, as well as to present an objective basis for the prevention of a similar accident and to secure data for the settlement of PL related disputes. It was found that in order to prevent the occurrence of accidents to transformers, insulating oil analysis, thermal image measurement, and corona discharge diagnosis, etc., were performed by establishing relevant regulation. The result of analysis performed on the external appearance of a transformer to which an accident occurred, the internal insulation resistance and protection system, etc., showed that most of the analysis items were judged to be acceptable. However, it was found that the insulation characteristics between the primary winding and the enclosure, those between the ground and the secondary winding, and those between the primary and secondary windings were inappropriate due to an insulating oil leak caused by damage to the pressure relief valve. From the analysis of the acidity values measured over the past 5 years, it is thought that an increase in carbon dioxide (CO2) caused an increase in the temperature inside the transformer and the increase in the ethylene gas increased the possibility of ignition. Even though 17 years have passed since the transformer was installed, it was found that the system's design, manufacture, maintenance and management have been performed well and the insulating paper was in good condition, and that there was no trace of public access or vandalism. However, in the case of transformers to which accidents have occurred, a melted area between the upper and the intermediate bobbins of the W-phase secondary winding as well as between its intermediate and lower bobbins. It can be seen that a V-pattern was formed at the carbonized area of the transformer and that the depth of the carbonization is deeper at the upper side than the lower side. In addition, it was found that physical bending and deformation occurred inside the secondary winding due to non-uniform pressure while performing transformer winding work. Therefore, since it is obvious that the accident occurred due to a manufacturing defect (winding work defect), it is thought that the manufacturer of the transformer is responsible for the accident and that it is lawful for the manufacture to investigate and prove the concrete cause of the accident according to the Product Liability Law (PLL).

• 농촌계획
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• 제23권1호
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• pp.53-63
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• 2017

Although some indicators for evaluating rural settlement conditions have been offered, these indicators could not reflect unique characteristics that rural has its own peculiarities. The rural area is identified with central districts functioned as service provision and hinterlands used its service. The aim of this study is to find a central district of rural villages and define range of its hinterlands using various physical characteristics of rural areas. Targeting areas are Yongsan and Hwanggan in Yeongdong-gun. The physical characteristics are represented by building density, number of shops among secondary and tertiary industries, official land price, and density of bus line. The rural central district is estimated by linear programming using defined the physical characteristics. Also its hinterlands used Huff model and social accessibility. The results of this study are as follows; (1) The physical characteristics in Hwanggan myeon is higher than Yongsan myeon because Hwanggan area has a large floating population for using Hwanggan station and ticket office; (2) The central district in Hwanggan has wider regional range than Yongsan. When central district estimate in rural areas, we suggest a grid diameter of Hexagon for controlling errors; (3) Considering accessibility, the life zone of 4 districts defined legally in Hwanggan use Yongsan and 2 legal districts in Hwanggan are possible to take advantage of Yongsan's life zone; (4) The results of survey targeting boundary villages between Yongsan and Hwanggan, individual drivers use central districts both Yongsan and Hwanggan, however users by public transportation (especially bus) go more to Hwanggan because bus lines to Hwanggan have many routes than to Yongsan. Evaluating the rural settlement conditions by national unit through grasping central districts and its hinterlands, these results can use as base line data and the evidence for regional development projects.

• 분석과 대안
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• 제2권1호
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• pp.31-69
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• 2018

This study examines the role of science in resolving trade disputes. After the Great East Japan Earthquake of 11 March 2011 that not only jeopardized the people of Japan, but also put the safety of an entire region at risk, the Republic of Korea (Korea) has imposed import bans as well as increased testing and certification requirements for radioactive material on Japanese food products. Japan has challenged these restrictions at the World Trade Organizations Dispute Settlement Body (DSB). This study aims to explain how international trade agreements and previous DSB rulings have dealt with different scientific viewpoints provided by confronting parties. In doing so, it will contrast the viewpoints espoused by Korean and Japanese representatives, and then analyzes the most similar case studies previously ruled on by the DSB, including the case of beef hormones and the case of genetically modified crops including biotech corn, both between the United States and the European Communities (EC). This study finds that science is largely subordinate to national interests in the case of state decision-making within the dispute settlement processes, and science has largely been relegated to a supportive role. Due to the ambiguity and lack of truly decisive decisions in the Appellate Body in science-based trade disputes, this study concludes that the Appellate Body avoids taking a firm scientific position in cases where science is still inconclusive in any capacity. Due to the panel's unwillingness to establish expert review boards as it has the power to do, instead favoring an individual-based system so that all viewpoints can be heard, it has also developed a system with its own unique weaknesses. Similar to any court of law in which each opposing party defends its own interests, each side brings whatever scientific evidence it can to defend its position, incentivizing them to disregard scientific conclusions unfavorable to their position. With so many questions that can arise, combined with the problems of evolving science, questions of risk, and social concerns in democratic society, it is no wonder that the panel views scientific information provided by the experts as secondary to the legal and procedural issues. Despite being ruled against the EC on legal issues in two previous cases, the EC essentially won both times because the panel did not address whether its science was correct or not. This failure to conclusively resolve a debate over whose science is more scientific enabled the EC to simply fix the procedural issues, while continuing to enforce trade restrictions based on their scientific evidence. Based on the analysis of the two cases of disputes, Korea may also find itself guilty of imposing an unwarranted moratorium on Japan's fish exports, only to subsequently pass new restrictions on labelling and certification requirements because Japan may have much scientific evidence at its disposal. However, Korea might be able to create enough uncertainty in the panel to force them to rule exclusively on the legal issues of the case. This will then equip Korea, like the EC in the past, with a way of working around the ruling, by changing whatever legal procedure they need to while maintaining some, if not most, of its restrictions when the panel fails to address its case on scientific grounds.

• 정보교육학회논문지
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• 제22권1호
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• pp.71-80
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• 2018

본 연구의 목적은 매년 우리나라의 전체 초중등학교를 대상으로 주기적으로 조사되고 있는 '교육정보화 실태조사'의 기초 데이터를 활용하여 2018년부터 필수화를 앞두고 있는 국내 SW 교육 준비 현황을 객관적으로 분석하는 데 있다. 이를 위해 교육정보화 실태조사 지표인 인적, 물적, 활용 지표 중 SW 교육과 관련된 지표를 추출하고 2014년부터 2016년까지 3개년 간의 국내 교육정보화 수준의 추이 변화를 분석하였다. 주요 연구 결과를 살펴보면 다음과 같다. 첫째, 정보교과를 담당하는 전체적인 교사 수는 3개년 간 지속적으로 늘어나고 있는 것을 알 수 있다. 하지만, 중학교의 정보 교과 담당교사 중 정보 컴퓨터 정교사 자격증 소지자 비율은 2014년(71%)부터 2016년(54%)까지 지속적으로 줄어들고 있으며, 타교과로 이동하는 정보 컴퓨터 전공 교사 수는 지속적으로 증가하는 역설적인 상황이 발생하고 있다. 둘째, 예산 및 인프라와 관련한 추이 분석 결과, 2014년부터 초 중등 학교운영비 대비 교육정보화 예산의 총액이 지속적으로 감소하는 것을 확인할 수 있었다. 셋째, 초등학교의 정보(컴퓨터) 관련 창의적 체험활동 운영 비율은 2015년 87.7%, 2016년 84.6%로 낮아졌으며, 중학교의 정보(컴퓨터) 교과 교육 운영 학교 비율 또한 2014년 34.8%, 2015년 30.8%, 2016년 28.2%로 점차 낮아지는 경향을 보이고 있다. 본 연구에서는 이러한 분석 결과를 토대로 초 중등 공교육 현장에 SW 교육의 안정적인 정착을 위한 방안을 제언하였다.

• 한국지반공학회논문집
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• 제24권8호
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• pp.99-109
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• 2008

본 연구는 군산 새만금지역의 점성토를 소성지수 15%, 30%, 45%, 60%가 되도록 벤초나이트를 첨가한 인공의 시료를 이용하여 하중재하기간을 1일, 2일, 4일, 8일 등으로 달리한 표준압밀시험을 실시하였다. 그리고 인천, 광양, 울산지역의 불교란 시료에 대한 압밀시험도 같이 수행하여 소성지수와 압밀하중재하기간이 2차 압밀에 어떤 영향이 있는지를 밝혔다. 그리고 각 소성지수에 따른 하중과 침하특성, 압밀계수특성, 압축지수 및 2차 압축지수특성, 간극수압특성을 밝히고 압축지수, 압밀계수, 2차 압축지수 등을 소성지수, 하중에 관하여 정식화하였다. 또한 정식화한 식을 이용한 1차 및 2차 압밀침하량 예측결과와 탄소성 구성모델인 수정 Cam-Clay모델과 탄 점소성 모델인 Sekiguchi모델을 이용한 예측결과를 모형시험 결과와 같이 비교하였다. 그 결과, 2차 압밀특성을 고려한 Sekiguchi모델이 매우 정도 높게 결과를 예측할 수 있음을 알 수 있었다.

• 한국사회복지학
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• 제62권2호
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• pp.187-208
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• 2010

본 논문의 목적은 1980, 90년대 독일의 '경과적 일자리 중심 노동통합형 사회적기업'이 공공부문의 재정건실화라는 의도를 통해 확대되는 현상을 분석하는 데 있다. 이를 위해 우선 독일 2차 노동시장의 개념과 유형을 고찰하고 2차 노동시장이 80년대 이 후 공공부문의 일자리창출 인프라로 지역사회에 정착되게 되는 과정을 분석하였다. 다음으로 2차 노동시장의 사회적기업이 공공부문의 재정건실화에 기여하고 있는 바를 기이센의 사례를 통해 <비용-편익> 분석으로 시도하였다. 마지막으로 독일의 경과적 일자리 중심 노동통합형 사회적 기업이 실업자 사회안전망으로 갖는 한계와 잠재력을 '공공부문으로의 종속화'와 '과도(過渡)노동시장의 형성'이라는 측면에서 논의하였다.

• 한국농공학회지
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• 제20권3호
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• pp.4750-4770
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• 1978

Under the various variations of the sample thickness, the load increment ratio and the load increment duration, this consolidation test of the clay in the Asan Bay was tried for the comparison with the standard consolidation test. The results gained are as follows; 1. The void ratio variations of the leached-clay samples were increasingly high, according as the sample thickness thinned and the load increment duration and the laod increment ratio increased. 2. The coefficient of consolidation were increased with the increment of the sample thickness, of the load increment ratio and of the load increment duration. Near the pre-consolidation load, the coefficient of secondary consolidation had the maximum value and lessened with the increment of the sample thicknss, and of the load increment duration 3. The value of the pre-consolidation load increased in proportion to the increment of the sample thickness and the decrease of the load increment ratio and the load increment duration. 4. The compression indices increased as the increment of load increased and decreased as the sample thickness increased. 5. The initial compression ratio increased as the sample thickness, the load increment ratio and the load increment duration decreased. The ratio of primary compression to the secondary decreased with the increment of the sample thickness and of the load increment ratio. 6. The time at the completion of psimary consolidation increased with the increment of the sample thickness and of the consolidation load, and with the decrease of the load increment ratio. 7. The compression indicses increaed as the sample thickness lessened and decreased as the load increment ratio increased. The coefficient of consolidation increased according as the sample thickness, the load increment ratio and the load increment duration went up. The settlement at the construction site should be calculated highly in proportion as the sample thickness lessened and the load increment ratio increased. The consolidation ratio is thought to be accelerated if the sample thickness and the load increment ratio becomes higher and the load increment duration longer.

• 상하수도학회지
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• 제32권1호
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• pp.47-53
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• 2018

This study investigated phosphorus removal from secondary treated effluent using coagulation-membrane separation hybrid treatment to satisfy strict regulation in wastewater treatment. The membrane separation process was used to remove suspended phosphorus particles after coagulation/settlement. Membrane separation with $0.2{\mu}m$ pore size of micro filtration membrane could reduce phosphorus concentration to 0.02 mg P/L after coagulation with 1 mg Al/L dose of polyaluminum chloride (PACl). Regardless of coagulant, the residual concentration of phosphorus decreased as the dose increased from 1.5 to 3.5 mg Al/L, while the target concentration of 0.05 mg P/L or less was achieved at 2.5 mg Al/L for the aluminum sulfate (Alum) and 3.5 mg Al/L for PACl. Moreover, alum showed better membrane flux as make bigger particles than PACl. Alum showed a 40% of flux decrease at 2.5 mg Al/L dose, while PACl indicated a 50% decrease of membrane flux even with a higher dose of 3.5 mg Al/L. Thus, alum was more effective coagulant than PACl considering phosphorus removal and membrane flux as well as its dose. Consequently, the coagulation-membrane separation hybrid treatment could be mitigate regulation on phosphorus removal as unsettleable phosphorus particles were effectively removed by membrane after coagulation.