• Title/Summary/Keyword: 전체기술효율성

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A study on efficient management of the drainages of underground tunnels for environmentally friendly urban railway systems (도시철도 친환경 지하터널 배수형식의 효율적인 유지관리 방안 검토)

  • Baek, Jong-Myeong;Hong, Jong-Hun;Kim, Han-Bae
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.1982-1990
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    • 2010
  • Excepting tunnel of dorimstream - ccachimountain station section, the subway line No.2th section was build using ASSM and NATM methods because of soil pressure and land condition. The way of dealing underground water was selected without sufficient preconsideration of geographical features, ground condition, influence of lowing underground water, and long-term cost of running maintenance so that the form of undrained tunnel was build having decreased construction characteristics and technically improper elements. The form of partial drainage is very difficult to manage structures of tunnel, because water leakage, water pressure causing cracks of lining concretes and scaling are constantly happened. so partial drainage suggest that setting reinforced Anchor Bolt to prevent buoyancy and should increase center drainage way up to height of railroad. Partial drainage suggest that holey pipe(${\phi}$350mm) manhole, drainage checking pipe manhole are should be regularly dredged, when changing roadbed(gravel${\rightarrow}$concrete) drainage checking pipe manhole should be build and setting a limitation of entering underground water's quantities. Beside drainage degree in changed section of structures causing instability of structures is continuous degree. so if efficient drainage way and the patterns of flaws, problems are considered in survey, it will be expected to have a advantage condition in maintenance part.

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A Study on Multi-modal Transport Logistics Network Buildup of Harbors in Gangwon in the North Pole Route Era (북극해 항로시대와 강원권 항만의 복합운송 물류네트워크 구축전략에 관한 연구)

  • Kim, Jae-jin;Lee, Kwang-keun;Jo, Jin-haeng
    • Journal of Korea Port Economic Association
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    • v.32 no.4
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    • pp.109-126
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    • 2016
  • This study investigates the initiatives of Gangwon sea routes based on precedent studies on the North Pole route to suggest a multi-modal buildup of transport logistics network of Gangwon harbors for the strengthening of logistics efficiency in the Korean Peninsula. The findings were: First, the government should expand railway infrastructure in Gangwon. Second, harbors in Gangwon should each have one speciality to strengthen connection with other harbors by using railway oriented background transportation network. Third, the government should develop industries of EFEZ(East coast Free Economic Zone) in the East Sea Coast in Gangwon to connect resources from the North Pole Sea. Fourth, the government should invite the base of Araon Ho's polar research vessel to play the role of the North Pole Sea route in the near future. Fifth, the government should strengthen the role of the Samcheock LNG base under construction. SIxth, environment-friendly transportation technology should be introduced to reduce carbon emission as much as possible. Lastly, an optimum North Pole logistics route should be developed to connect the Metropolitan area(Metropolitan Economic Zone), Gangwon roads and railway, Gangwon habor, Trans-Siberian Railway and thw North Pole route, and Europe, to strengthen national foreign trade power in the near future.

A Productivity Analysis Method of Curtain Wall Works Using Construction Simulation (건설 시뮬레이션을 활용한 커튼월 적층공법의 생산성 분석방안)

  • Park, Dong-Geun;Lee, Kyung-Suk;Yu, Byung-In;Kim, Young-Suk;Han, Seung-Woo
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • 2008.11a
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    • pp.256-261
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    • 2008
  • The curtain-wall work has been more frequently applied in the construction industry since demand of high-rise buildings has been increased. The curtain-wall work is usually performed with the frame work simultaneously for reducing construction period, but it might be delayed because of several problems caused by interference of process. However, there is not an appropriate tool which can be used by a work manager for adjusting quantity of the construction equipments or the workers when the curtain-wall work was delayed. To resolve this problem a construction simulation anticipating and analyzing potential problems before starting the work can be applied in the curtain wall work. This research suggests a general model for the curtain-wall work by using construction simulation and produces a combination of construction equipments and workers which can estimate optimum work productivity.

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Comparing Attitudes to Emergency Grant for all Citizen in the News Articles (전국민재난지원금에 대한 신문기사 보도태도 차이·변화 연구)

  • Bae, Hwa-Sook
    • The Journal of the Korea Contents Association
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    • v.21 no.9
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    • pp.806-816
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    • 2021
  • This study aims to describe the reporting patterns of articles on the Emergency Grant for all citizens(EGAC) and compare the reporting attitudes by newspaper companies. The main results are as follows: First, conservative newspapers reported more than four times as much coverage of EGAC as liberal newspapers. Newspaper articles reported during the week of the National Assembly Election Day accounted for about a quarter of the total, and 79.1% of the articles were reported in the political realm of newspapers, and only 2.8% in the social realm. Second, a conservative newspaper reported a critical attitude toward EGAC at 52.6% and favorable articles at 5.3%. On the other hand, in a liberal newspaper, critical articles were 17.1% and favorable articles were 37.1%. The inefficiency of selectivism was reported as the basis for the argument in favor, and concerns about the burden of deterioration in the financial soundness of the opponents were reported the most. Politicians are the most cited sources of information in articles. Finally, in prior to policymaking, the proportion of the media in favor of and against the news was similar, and the proportion of articles with a neutral attitude accounted for more than half. And in the specific method discussion stage, the articles in favor of the article exceeded the proportion of articles on the opposite side.

A Comparative Study of University Students' Satisfaction on the Online Courses between Primary & Secondary Teachers' University: Focused on the English-Related Subjects (온라인 영어강좌에 대한 대학생들의 수업만족도 분석연구: 초등예비교사와 중등예비교사의 비교)

  • Lee, Seungbok;Yoon, Tecnam
    • The Journal of the Korea Contents Association
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    • v.21 no.2
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    • pp.386-394
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    • 2021
  • This study aims to investigate the class satisfaction of the students enrolled in between a primary and secondary teacher's college, and to identify any statistical differences among the class satisfaction factors. In order to answer these questions, a survey of 50 questionnaires were distributed to 54 primary teachers' college students and 50 secondary teacher's college ones, respectively. A survey consisted of 5 categories including class contents, instruction results, class environment, instructional supports and efficiency. To analyze data, the descriptive analysis and independent sample t-test were administerd using Jamovi statistical program. The results revealed that there was no significant difference between two groups in terms of the overall class satisfaction, even though the mean score from the secondary teachers' college students was higher than that of the primary teachers' college students. However, there was a significant difference in the class satisfaction's sub categories: class environment, instructional supports and efficiency.

Causes of accidents and preventive measures due to defects in pump car booms (펌프카의 붐대 결함에 의한 사고원인과 방지대책)

  • Cho Choonhwan
    • Journal of the Korea Institute of Construction Safety
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    • v.6 no.1
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    • pp.7-11
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    • 2024
  • Pump car is an equipment that transports concrete products as needed to the place where they are poured. In order to pour a large amount of concrete in a short period of time, using a pump car is the most efficient in terms of economic efficiency and quality control. However, recently, many casualties have occurred due to boom damage during concrete pouring, so this study suggests that improvements are needed in the equipment manufacturing stage, inspection standards for old equipment, and equipment rental system. The reason is that, as a result of the finite element analysis of the pump car, the significant stress acting at the second stage of the boom and the maximum stress at the top of the boom were found to be 895.39 MPa, and M.S. Since it was evaluated the lowest at 0.04, the need for reinforcement was recognized. And it was confirmed that the 2nd stage boom was the most stressful and vulnerable part of the 1st to 5th stage booms. Therefore, it is necessary to increase the thickness and rigidity of members at the design and manufacturing stage, and to reinforce the steel plates of currently used equipment. In addition, it is urgent to establish a system that makes non-destructive testing mandatory for all general construction machinery and holds inspection agencies responsible for missing boom defects during non-destructive testing and regular inspections.

World Logistics Evolution & Marketing Strategy for Korea's Enhanced Port Competition (세계물류발전과 한국의 항만경쟁력 강화를 위한 마케팅 전략)

  • Gim, Jin-Goo
    • Journal of Korea Port Economic Association
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    • v.24 no.4
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    • pp.363-384
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    • 2008
  • This study aims at improving Korea's competitiveness in port logistics through marketing strategy with integrating the conceptual approach into the empirical one and combining both the oldest military treatise and the newest evaluating model in social science that was applied by the HFP(hierarchical fuzzy process) model enhanced by the KJ method. The empirical results of this study show Busan in the middle among subject ports. At present, Korea plays a reciprocal role in the port market in East Asia, but in the medium- and long-term, Korea's ports will vie together with most major ports in the East Asian region. A descriptive investigation shows that Korea's developing tasks in port logistics must be considered in the context of the direction for developing port policies, the necessity of expanding port facilities in the capital region, securing the sufficient traffic volume through the establishment of the hinterland linking system and its positive utilization, and reforming the direction for developing the global logistics through increased port competitiveness. In the short- and medium-term, Korea must use the opportunity factor of 'Growth and open door policy of China' as a geoeconomic advantage and to utilize Korea's ports as a gate to Chinese foreign trade. With the rise of China's economy, China also plays a significant role in both port and airport markets. Hence, the linking system between the two must be established to meet the expanding traffic volume, especially in the capital area. Moreover, it is necessary for Korea to secure port logistics through the establishment of the hinterland linking system and its positive utilization. The great accomplishment of this paper is to present strategies to increase Korea's port competitiveness in the rapidly changing environments of world logistics with the focus on both the oldest military strategic treatise and the newest empirical method in social science. In order to reinforce this study, it needs further compensative research because the evaluation structure could be subdivided with more extensive and precise criteria.

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A novel cold-active lipase from Psychrobacter sp. ArcL13: gene identification, expression in E. coli, refolding, and characterization (새로운 Psychrobacter sp. ArcL13 유래 저온활성 지질분해효소 : 유전자 분리동정, 대장균에서의 발현, refolding 및 특성 연구)

  • Koo, Bon-Hun;Moon, Byung-Hern;Shin, Jong-Suh;Yim, Joung-Han
    • Korean Journal of Microbiology
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    • v.52 no.2
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    • pp.192-201
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    • 2016
  • Recently, Psychrobacter sp. ArcL13 strain showing the extracellular lipase activity was isolated from the Chuckchi Sea of the Arctic Ocean. However, due to the low expression levels of the enzyme in the natural strain, the production of recombinant lipase is crucial for various applications. Identification of the gene for the enzyme is prerequisite for the production of the recombinant protein. Therefore, in the present study, a novel lipase gene (ArcL13-Lip) was isolated from Psychrobacter sp. ArcL13 strain by gene prospecting using PCR, and its complete nucleotide sequence was determined. Sequence analysis showed that ArcL13-Lip has high amino acid sequence similarity to lipases from bacteria of some Psychrobacter genus (84-90%) despite low nucleotide sequence similarity. The lipase gene was cloned into the bacterial expression plasmid and expressed in E. coli. SDS-PAGE analysis of the cells showed that ArcL13-Lip was expressed as inclusion bodies with a molecular mass of about 35 kDa. Refolding was achieved by diluting the unfolded protein into refolding buffers containing various additives, and the highest refolding efficiency was seen in the glucose-containing buffer. Refolded ArcL13-Lip showed high hydrolytic activity toward p-nitrophenyl caprylate and p-nitrophenyl decanoate among different p-nitrophenyl esters. Recombinant ArcL13-Lip displayed maximal activity at $40^{\circ}C$ and pH 8.0 with p-nitrophenyl caprylate as a substrate. Activity assays performed at various temperatures showed that ArcL13-Lip is a cold-active lipase with about 40% and 73% of enzymatic activity at $10^{\circ}C$ and $20^{\circ}C$, respectively, compared to its maximal activity at $40^{\circ}C$.

The Evaluation of Usefulness of Two Times Elution a Day of $^{99m}Tc$ Using $^{99}Mo$-$^{99m}Tc$ Generator ($^{99m}Tc$ 발생기의 24시간 내 2회 용출의 유용성 평가)

  • Kim, Jeong-Ho;Seo, Han-Kyung;Jeong, Yeong-Hwan;Kim, Yeong-Su;Kim, Byung-Cheol;Gwon, Yong-Ju;Lee, Jeong-Ok;Park, Yeong-Sun;Kim, Dong-Yun
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.2
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    • pp.83-86
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    • 2010
  • Purpose: The Molybdenum which is the raw material of $^{99}Mo$-$^{99m}Tc$ generator (generator) is produced from the nuclear reactor. However, output has dwindled as the two nuclear reactors supplying the bulk of radioactive material-one in Chalk River, Ontario and the other in Petten, the Netherlands-have been closed for repairs or maintenance. This resulted in the enhancement of its price. Therefore we have tried to seek the new method which could run generator to increase activity of $^{99m}Tc$ in this study. Materials and Methods: The $^{99m}Tc$ activity obtained from 5 times elution for 5 days from Monday to Friday using two generators was compared with 10 times elution. Appearance test, pH test, LAL test, sterility test, chemical impurity(Al) test, radio chemical purity test, ratio of $^{99}Mo$/$^{99m}Tc$ activity test have been done to check the stability of $^{99m}Tc$ eluting from generator respectively. Results: The $^{99m}Tc$ activity obtained from 5 times elution for 5 days was 168.2 GBq (4545 mCi) and 10 times was 230.5 GBq (6230 mCi). All quality control tests were within normal limit. Conclusion: We got to know that 2 times elution a day obtained more $^{99m}Tc$ activity than one time elution in this study.

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Study on the establishment of an efficient disaster emergency communication system focused on the site (현장중심의 효율적 재난통신체계 수립 방안 연구)

  • Kim, Yongsoo;Kim, Dongyeon
    • Journal of the Society of Disaster Information
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    • v.10 no.4
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    • pp.518-527
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    • 2014
  • Our society is changed and diversified rapidly and such tendency is accelerated day after day and has made a lot of problems in the many fields. The important thing we have to recognize is such tendency has a bad effect recently on the safety system in Korea. So it is time to enhance the national safety system and moreover recently Sewol-ho(passenger ship) went down in the sea, it made people remind the importance of national safety system. With this incident, Korean government decided to establish the national safety communication network against the disaster. At this time, I will propose several ideas about the national safety communication network. 1. It must to be established an unified network to contact people who is on a disaster site anytime and anywhere. This is most important element on all disaster sites. 2. PS-LTE technology must to be adopted to the network because it has many advantages including various multimedia services compared to the TETRA in the past. 3. 700MHz is the most efficient band for the network because it has wide cell sites coverage compared to 1.8GHz. 4. Satellite communication system is needed to the network for back-up. 5. It will be effective to adopt Social Media to the communication network system like a Twitter or Facebook for sharing many kinds of information and notifying people of warning message. 6. It can make the network more useful to introduce the latest technology like a sensor network. And Korean government has to improve the system related to the disaster including law and operating organization.