• Wind and Structures
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• 제23권6호
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• pp.595-613
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• 2016

Large amplitude oscillation of steepled main cables usually presents during construction of a long-span bridge. To study this phenomenon, six typical main cables with different cross sections during construction are investigated. Two main foci have been conducted. Firstly, aerodynamic coefficients of a main cable are obtained and compared through simulation and wind tunnel test: (1) to ensure the simulation accuracy, influences of the numerical model's grid size, and the jaggy edges of main cable's cross section on main cable's aerodynamic coefficients are investigated; (2) aerodynamic coefficients of main cables at different wind attack angles are obtained based on the wind tunnel test in which the experimental model is made by rigid plastic using the 3D Printing Technology; (3) then numerical results are compared with wind tunnel test results, and they are in good agreement. Secondly, aerodynamic coefficients of the six main cables at different wind attack angles are obtained through numerical simulation. Then Den Hartog criterion is used to analyze the transverse galloping of main cables during construction. Results show all the six main cables may undergo galloping, which may be an important reason for the large amplitude oscillation of steepled main cables during construction. The flow structures around the main cables indicate that the characteristic of the airflow trajectory over a steepled main cable may play an important role in the galloping generation. Engineers should take some effective measures to control this harmful phenomenon due to the big possibility of the onset of galloping during the construction period.

• Physical Therapy Rehabilitation Science
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• 제8권2호
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• pp.99-110
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• 2019

Objective: The aim of the present study was to develop a valid and reliable scale that measures the healthy life styles among young adults. Design: A methodological study design was employed to develop and validate the Healthy Lifestyle Screening Tool (HLST). Methods: The validity and reliability of the HLST were established in accordance with DeVellis' 8 steps guideline for tool development. The question items were generated based on literature reviews and interviews, which were then classified into 12 categories. The HLST was administered to 272 students attending a Korean university. The reliability was tested using Cronbach's alpha. The validity of the scale was examined with the mean inter-item correlations (MIIC) and factor analysis, and was also examined for content validity by experts. Results: The reliability of the HLST was found to be acceptable, as indicated by a Cronbach's alpha of 0.71. In the validity test, items with less than 80% "agreement" ratings on the content validity index by experts were revised. The MIIC values were greater than 0.25. A factor analysis of 36 items extracted 9 factors (i.e., four items per factor), which together explained 50.4% of the variance. The HLST consists of 36 items that measure 9 factors based on a 4-point Likert rating scale, with 4 items per factor, as follows: sunlight, water, air, rest, exercise, nutrition, temperance, trust, and general physical condition. High scores on the HLST are indicative of a healthy lifestyle (HL). Conclusions: The HLST is a valid and reliable scale that can be used to measure HL among young adults. Identification of HL by using the HLST can provide guidance to integrated therapeutic approaches along with conventional physical therapy.

• 환경정책연구
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• 제1권1호
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• pp.111-128
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• 2002

The Ministerial Declaration of the 4th WTO Ministerial Meeting at Doha in November 2001 announced the launch of the New Round and a completion date of January 1st, 2005. It agreed to eventually negotiate trade and environment linkage issues, such as the relationship between the WTO rules and Multilateral Environment Agreements and the reduction or elimination of tariff and non-tariff barriers to environmental goods and services. The Committee on Trade and Environment was instructed to pursue work on all items on its agenda within the current terms of reference and to give particular attention to the effects of environmental measures on market access, relevant provisions of the TRTPS Agreement, and labelling requirements for environmental purposes. This means that far the first time, the members of the WTO will discuss and negotiate trade and environment linkage in the framework of multilateral trade negotiation. Korea, from the standpoint of a smaller open economy heavily dependent on international trade, is obliged to overcome the challenges imposed by the environment agenda in the Doha declaration. This study examined the linkage among environment, economic growth and international trade in order to review the possible trade and environment policy implications in Korea. Mutual supportiveness of trade and environment depends much on the effectiveness of trade and environment policy coordination. In this regard, we conclude that the Korean government should provide an appropriate institutional framework to promote closer cooperation among policy makers engaged in negotiations. Trade and environment policy review and environmental impact assessment of trade negotiation should be considered as a work programme of this institutional policy coordination framework.

• 한국의학물리학회지:의학물리
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• 제32권3호
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• pp.59-69
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• 2021

Purpose: The relationship between computed tomography (CT) number and electron density (ED) has been investigated in previous studies. However, the role of these measures for guiding cancer treatment remains unclear. Methods: The CT number was plotted against ED for different imaging protocols. The CT number was imported into ED tables for the Pinnacle treatment planning system (TPS) and was used to determine the effect on dose calculations. Conversion tables for radiation dose calculations were generated and subsequently monitored using a dosimeter to determine the effect of different CT scanning protocols and treatment sites. These tables were used to retrospectively recalculate the radiation therapy plans for 41 patients after an incorrect scanning protocol was inadvertently used. The gamma index was further used to assess the dose distribution, percentage dose difference (DD), and distance-to-agreement (DTA). Results: For densities <1.1 g/cm³, the standard deviation of the CT number was ±0.6% and the greatest variation was noted for brain protocol conditions. For densities >1.1 g/cm³, the standard deviation of the CT number was ±21.2% and the greatest variation occurred for the tube voltage and head and neck (H&N) protocol conditions. These findings suggest that the factors most affecting the CT number are the tube voltage and treatment site (brain and H&N). Gamma index analyses for the 41 retrospective clinical cases, as well as brain metastases and H&N tumors, showed gamma passing rates >90% and <90% for the passing criterion of 2%/2 and 1%/1 mm, respectively. Conclusions: The CT protocol should be carefully decided for TPS. The correct protocol should be used for the corresponding TPS based on the treatment site because this especially affects the dose distribution for brain metastases and H&N tumor recognition. Such steps could help reduce systematic errors.

• Journal of Preventive Medicine and Public Health
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• 제54권4호
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• pp.221-229
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• 2021

Objectives: The Indonesian government issued large-scale social restrictions (called Pembatasan Sosial Berskala Besar, or PSBB) at the beginning of the coronavirus disease 2019 (COVID-19) pandemic to control the spread of COVID-19 in Jakarta, Bogor, Depok, Tangerang, and Bekasi (Greater Jakarta). Public compliance poses a challenge when implementing large-scale social restrictions, and various factors have contributed to public non-compliance with the regulation. This study aimed to determine the degree of non-compliance and identify the factors that contributed to public non-compliance with the PSBB in Greater Jakarta, Indonesia. Methods: This was a quantitative study with a cross-sectional design. A total of 839 residents of Greater Jakarta participated in this study. Data were collected online using a Google Form, and convenience sampling was undertaken. Univariate and multivariate analyses were performed to explore the relationships between public non-compliance with the PSBB regulation and socio-demographic variables, respondents' opinion of the PSBB, and social capital. Results: A total of 22.6% of subjects reported participating in activities that did not comply with the PSBB. The variables that most affected non-compliance with the PSBB were age, gender, income, opinion of the PSBB, and social capital. Conclusions: Strengthening social capital and providing information about COVID-19 prevention measures, such as washing one's hands with soap, wearing masks properly, and maintaining social distancing, is essential. Robust public understanding will foster trust and cooperation with regard to COVID-19 prevention efforts and provide a basis for mutual agreement regarding rules/penalties.

• 한국포장학회지
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• 제5권2호
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• pp.42-58
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• 1999

Packaging materials and articles that are used in food contact applications can transfer constituents in the foodstuffs. This kind of risk of possible health hazards to consumers has been generally recognized for a long time with the consequence of establishing corresponding food regulations in most developed countries. However, the language of these laws, their interpretation, and their level of enforcement vary from country to country. Accordingly, the actual migrating levels from packaging materials can be varied depending on the migration testing methods as prescribed in the national legislation in each countries. Therefore, there are needs of elimination of non-tariff trade barriers raised by sanitary and phytosanitary or technical measures under the Final Act of the UR Agreement. In this connection, the EU and USA are currently in an ongoing process of legislation harmonization to overcome potential barriers to free trade. In general, regulations governing component transfer in the USA are more complicated and comprehensive than similar regulations in Europe. In future, standard migration testing procedures for microwave heat susceptor materials and for the use of fatty food simulant should be established and also harmonized among countries. The objective of this investigation is to compare the current regulations for migration testing for plastic containers and packaging materials in USA, EU and Korea or Japan. For those regulations, Korean standards are required to be kept up with the international standards. By doing this, the related Korean regulation could be amended along with the worldwide progress for harmonization.

• 무역상무연구
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• 제39권
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• pp.59-85
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• 2008

An independent bank guarantee(aka an independent guarantee) is provided as an security on a principal obligor's performance of his obligation, and a guarantor should pay the guaranteed amount only upon a beneficiary's written demand. A standby letter of credit has been used in the United States, since it was construed that a bank should not issue a guarantee. There was wide misunderstanding that a standby letter of credit differs from an independent bank guarantee. However, a standby letter of credit is the same security as an independent bank guarantee, and in international business a standby letter of credit is not differentiated from a independent bank guarantee. An independent bank guarantee are independent from the underlying contract, unconditional, and irrevocable. And a guarantor should pay upon written demand without proving a principal obligor breaches the underlying contract. These features of an independent bank guarantee has been abused in international transactions. Thus it has been proposed that some exceptions to the features of an independent bank guarantee should be allowed. United Nations Convention on Independent Guarantees and Standby Letter of Credit(1995) stipulates some exceptions to payment obligation. Export bond insurance, a part of export insurances, operated by the Korea Export Insurance Corporation under the Export Insurance Act, is used as a security for unfair calling by a beneficiary under an independent bank guarantee. Most of the export subsides by the government are prohibited under WTO's Agreement on Subsidies and Countervailing Measures. However, as export insurance is allowed under the WTO, it operates a significant role in enhancing the export. In the event that export bond insurance is provided for a guarantor, an obligor who is subject to recourse by a guarantor, can be exempt from the recourse in case of unfair calling. The Korea Export Insurance Corporation, an insurer, bears unfair calling risk by a beneficiary. Generally it is understood that a demand shall be made before the expiry of an independent bank guarantee. However this is not absolutely true, it shall be decided by URDG, ISP98, the governing law.

• 한국건설관리학회논문집
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• 제6권1호
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• pp.186-194
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• 2005

본 연구는 건설공사 하도급계약의 당사자인 수급인과 하수급인간의 하도급계약금액 조정과 관련하여 발생하는 원인을 검토하고, 분쟁을 예방하기 위한 하도급대금조정 관련 법규의 개선방안을 제시하는 것을 목적으로 한다. 본 연구는 문헌연구, 하도급계약 법규에 관한 구조와 맥락의 분석 그리고 설문조사의 방법에 의하여 진행되었으며, 주요한 연구결과는 다음과 같다. (1) 발주자와 수급인의 계약금액 조정이 이루어지는 경우 그 내용을 하수급인에게 통지하도록 하는 절차에 관한 조항을 하도급법과 건설표준하도급계약조건에 규정하여야 한다. (2) 하수급인이 하도급계약 내용의 변경 및 그에 수반되는 하도급대금 조정을 청구할 수 있도록 하는 절차를 건설표준하도 급계약조건에 규정하여야 한다. (3) 하도급대금 조정에 관한 기준을 명확히 하기 위하여 건설표준하도급계약조건에서 사용되고 있는 불확정 개념인 단가, 낙찰률 등 용어의 정의를 명확히 하였다. (4) 수급인의 귀책으로 인해 발생하는 연장비용의 부담은 수급인이 부담하도록 하여 부담의 주체를 명확히 하고 연장비용의 산정기준으로 재정 경제부 제정 실비산정규정을 적용하여야 한다.

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2410-2414
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• 2020

Heavy ions have a high potential for destroying deep tumors that carry the highest dose at the peak of Bragg. The peak caused by a single-energy carbon beam is too narrow, which requires special measures for improvement. Here, carbon-12 (¹²C) ion with different energies has been used as a source for calculating the dose distribution in the water phantom, soft tissue and bone by the code of Monte Carlobased FLUKA code. By increasing the energy of the initial beam, the amount of absorbed dose at Bragg peak in all three targets decreased, but the trend for this reduction was less severe in bone. While the maximum absorbed dose per bone-mass unit in energy of 200 MeV/u was about 30% less than the maximum absorbed dose per unit mass of water or soft tissue, it was merely 2.4% less than soft tissue in 400 MeV/u. The simulation result showed a good agreement with experimental data at GSI Darmstadt facility of biophysics group by 0.15 cm average accuracy in Bragg peak positioning. From 200 to 400 MeV/u incident energy, the Bragg peak location increased about 18 cm in soft tissue. Correspondingly, the bone and soft tissue revealed a reduction dose ratio by 2.9 and 1.9. Induced neutrons did not contribute more than 1.8% to the total energy deposited in the water phantom. Also during ¹²C ion bombardment, secondary fragments showed 76% and 24% of primary 200 and 400 MeV/u, respectively, were present at the Bragg-peak position. The combined treatment of carbon ions with neutron or electron beams may be more effective in local dose delivery and also treating malignant tumors.

• 설비공학논문집
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• 제29권5호
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• pp.239-248
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• 2017

At the $21^{st}$ Conference of the Parties (COP) of the United Nations Climate change Conference, representatives of the 195 member countries reached an agreement requiring all participating countries, including Korea, to establish proactive measures to fight climate change. Under this vision, energy network technologies are deemed as a key site of research towards meeting this goal. Herein, the headquarters of the Korea Institute of Energy Research (KIER) is a worthy site for carrying out energy network technology research insofar as it contains various heat sources. To prepare for this research, a study was conducted analyzing the heat sources at KIER based on measured data. The study also consisted of developeding simulation models to predict the amount of energy savings that could be derived by replacing an absorption chiller/heater with an absorption heat pump during winter seasons. In our simulation results, we observed a primary energy saving ratio of 65~72% based on the water temperature from the heat source of a coal power plant.