• 한국항행학회논문지
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• 제25권1호
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• pp.78-83
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• 2021

급속도로 증가하는 항공 교통량으로 인한 공역 과밀화와 공역제한으로 인해 국제민간항공기구(ICAO) 에서는 공역 수용 증대를 위한 performance-based navigation 을 실시하기 위해 2025년 까지 모든 항공기들을 대상으로 하여 SBAS 사용을 촉구하고 있는 실정이다. 이에 맞춰 국내 역시 한국의 공역환경 특성을 반영한 한국형 SBAS의 연구 개발을 지속중이다. 국내에서는 아직 SBAS의 성능 시험 및 검증을 위한 비행검사 절차 및 이에 필요한 탑재장비 구성방안이 수립되어 있지 않으므로 본 논문에서는 FAA, ICAO 규정집, 그리고 국토교통부가 제정한 법령을 분석하여 향후 수립될 한국형 SBAS의 필수 평가 사항들과 파라미터들을 도출하고, RTCA 규정집을 참고하여 RTK-DGPS 위치고정 시스템을 이용한 비행검사 최적 장비 구성방안에 대해 제시하였다.

• 한국환경과학회지
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• 제30권5호
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• pp.391-397
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• 2021

This study aims to establish the measures required for strengthening the internal stability of and executing the systematic plan for Gangwon-do in relation to the "urban regeneration preliminary project" launched by the Ministry of Land, Infrastructure, and Transport. The results of this study are as follows. The unit project carried out via the Gangwon-do urban regeneration preliminary project presented the tendency for the standardization of the H/W and S/W projects such as the establishment of the community anchor space and the resident competency reinforcement project. Further, rather than focusing on the contents that could objectively measure the effects of the project, it concentrated more on the performance indicators that are required for verifying the execution of unit projects like the establishment of buildings and operating programs. It was found to be insufficient with regard to the practicality of the project, the correlation with the New Deal Project, and the validity of the project contents. To improve these aspects, Gangwon-do would be required to highlight its distinguishability from the other regions and increase its practicality by operating the field-centered urban regeneration educational program, inducing the participation of experts in each of the areas in case there is a need to execute a project plan and discover a project with placeness. It also needs to focus on strengthening its connection with the urban regeneration new deal project by discovering the resident leaders and professional manpower, and establishing the performance indicators needed for systematically monitoring the regional changes in accordance to the urban regeneration preliminary project.

• Journal of Korea Trade
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• 제23권6호
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• pp.113-130
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• 2019

Purpose - This paper investigates applicability of blockchain based bill of lading under the current legal environment. Legal requirements of electronic bill of lading will be analyzed based on the Rotterdam Rules and recently enacted UNCITRAL Model Law on Electronic Transferable Records. Using comparative analysis with the previous registry model for electronic bill of lading, this paper examines the advantages of blockchain based bill of lading. Design/methodology - This research reviewed previous efforts for dematerializing bill of lading with its limitation. Main features of blockchain technology which can make up for deficiencies of registry model also be investigated to analyze whether these features can satisfy the requirements for the legal validity of the negotiable electronic transport record or electronic transferable records under the Rotterdam Rules and the MLETR. Findings - Main findings of this research can be summarized as follows: Blockchain system operated in an open platform can improve transparency and scalability in transfer of electronic bill of lading by assuring easy access for transaction. Distributed ledger technology of blockchain makes it more difficult to forge or tamper with transactions because all participants equally shares identical transaction records. Consensus mechanism and timestamp in a blockchain transaction guarantee the integrity and uniqueness of a transaction. These features are enough to satisfy the requirements of electronic transferable records under the Rotterdam Rules and MLTER. Originality/value - This study has significance in that it provided implications for the introduction of electronic bill of lading by analyzing whether the blockchain based electronic bill of lading model meets the legal requirements under the current legal system prepared prior to the introduction of blockchain technology, and by presenting the advantages of the blockchain based bill of lading model through comparative analysis with the existing registry model.

• 화약ㆍ발파
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• 제40권3호
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• pp.1-18
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• 2022

수소 경제 시대의 도래로 인해 수소 운송, 저장을 하기 위해 다양한 연구들이 진행되고 있으며, 그로 인한 수소 폭발의 위험성이 대두되고 있다. 수소 에너지와 관련된 최신 기술 현황을 파악하기 위하여 국내외 다양한 수소 에너지와 관련된 전체적인 연구동향을 파악하는 것이 필요하다. 이와 관련하여 본 논문에서는 국제 학술지에서 게재된 전체 논문을 대상으로 VOSViewer를 이용한 계량서지분석을 실시하였다. 수소 폭발, 수소 파이프라인, 수소 저장의 시기별 핵심단어 분석 결과, 수치해석 시뮬레이션을 활용한 논문들이 많이 게재되고 있었으며, 2000-2010년에 비해 2011-2022년에는 수소 저장, 수소 파이프라인 연구 분야에서 안전성과 수소 폭발에 대한 연구가 더욱 더 많이 진행되고 있었음을 알 수 있다.

• 한국환경과학회지
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• 제31권9호
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• pp.743-755
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• 2022

This study aims to review the differences in urban regeneration independently implemented by the government (Ministry of Land, Infrastructure, and Transport, MOLIT) and Seoul based on related laws and ordinances, and to draw out the implications of Korean urban regeneration's directions. The results are as follows. First, Seoul has constantly responded to the revision of the Urban Regeneration Act by adjusting and specifying the contents of ordinances, and especially, there have been efforts to enhance regional characteristics suitably for the circumstances of Seoul. Second, in the urban regeneration of Seoul, the budgets including the matching ratio of national and local subsidies shall be changed according to the standards of the MOLIT in changing designating places after the selection of the urban regeneration by the ministry, and this procedure and these implementation methods cause confusion to Seoul and local governments. Third, there were differences in the results of comparing the budgets and support methods of the "Gaggum Housing Project" of Seoul and "New Deal Housing Repair Project" of the MOLIT, which caused conflicts due to the differences in the project implementation and support standards, and the arbitrary interpretation of the guidelines. Although the urban regeneration greatly contributed to the revelation and conservation of regional characteristics, it might be necessary to establish systems that can enhance citizens' awareness and compensate the efficient contents needed for each region in the future.

• 한국항공우주학회지
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• 제50권9호
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• pp.647-655
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• 2022

러시아 정부는 세계 3위의 민간항공기 생산 강국을 목표로 민간항공기 제작기술 및 첨단 소재 확보를 위해 외국과 생산 제휴 등 전략적 협력을 확대하는 중이다. 또한 러시아 정부는 항공기 제작산업의 발전을 지원하고 항공 인증 조직을 개편하여 체계적인 항공안전 확보를 추구하고 항공제품 수출을 위한 국제협력과 인증활동에 많은 노력을 기울이고 있다. 국가 간에 민간항공기 안전 및 인증분야의 협력체계를 구축하기 위해서는 전반적인 인증시스템에 대한 상호간의 이해와 신뢰를 구축하는 과정이 요구된다. 따라서 본 연구에서 러시아의 항공기 인증조직, 법령체계, 인증절차를 분석하여 러시아의 항공기 인증체계에 대한 이해를 돕고자 하였다.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.242-249
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• 2009

High-rise construction sites, especially those situated in spatially constrained urban areas, have difficulties in timely delivery of materials. Modern techniques such as Just-in-time delivery, and use of information technology such as Project Management Information System (PMIS), are targeted to improve the efficiency of the logistics. Such IT-driven management techniques can be further benefited from state-of-the-art devices such as Radio Frequency Identification (RFID) tags and Ubiquitous Sensor Networks (USN), which has resulted in notable achievements in automated logistics management at the construction sites. Based on those achievements, this research develops USN hardware toolkits for construction lifts, which aims to be automated the vertical material delivery by sensing the material information and routing it automatically to the right place. The gathered information from the sensors can also be used for monitoring the overall status. The developed system will be tested in the actual high-rise construction sites to assess the system's feasibility. The proposed system is being implemented using Zigbee communication modules and RFID sensor networks which will communicate with the intelligent palette system (previously developed by the authors). To support the system, a lift-mountable intelligent toolkit is under development. Its feasibility test will be conducted by applying the implemented system to a test bed and then analyzing efficiency of the system and the toolkit. The collected test data will be provided as a basis of autonomous vertical transport equipment development. From this research, efficient management of the material lift is expected with increased accuracy, as well as better management of overall construction schedule benefited from the system. Further research will be expected to develop a smart construction lift, which will eliminate the need for human supervision, thus enabling a real 'autonomous' operation of the system.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.238-244
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• 2022

Civil projects are associated with many uncertainties because they involve a long duration, many resources, a large area, and many supply chains. Therefore, the price of a civil project is not simply proportional to the quantity and unit price of the item but has a variable value, including uncertainty risk. This study investigates the influence of the uncertainty factors in the pre-bid clarification document on bid price formation during the project bidding phase. To this end, civil projects from the California Department of Transportation (Caltrans) were used as research data. This study randomly selected fifty sample data from each of twelve counties from 2008-to 2020: six hundred. The authors observed that each project sample had 0 to n query cases due to uncertainty. Then, this study examined the project uncertainty cases and categorized them into the following four uncertainty factors: 'conflict' (UF1), 'impossibility' (UF2), 'lack' (UF3), and 'missing' (UF4). Under the extracting process, the cases are classified into four uncertainty factors. With the project not containing any uncertainty factors as a control group, the project containing these uncertainty factors was designated as an experimental group. After comparing the bidder's price, the experimental group's bid price was higher than the control group's. This result suggests that uncertainty factors in bid documents induce bidders to set a high bid price as a defense against uncertainty.

• Journal of Radiation Protection and Research
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• 제48권1호
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• pp.44-51
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• 2023

Background: Aptamers are currently being used in various fields including medical treatments due to their characteristics of selectively binding to specific molecules. Due to their special characteristics, the aptamers are expected to be used to remove radionuclides from a large amount of liquid radioactive waste generated during the decommissioning of nuclear power plants. The radiological effects on the aptamers should be evaluated to ensure their integrity for the application of a radionuclide removal technique. Materials and Methods: In this study, Monte Carlo N-Particle transport code version 6 (MCNP6) and Monte Carlo damage simulation (MCDS) codes were employed to evaluate the radiological effects on the aptamers. MCNP6 was used to evaluate the secondary electron spectrum and the absorbed dose in a medium. MCDS was used to calculate the DNA damage by using the secondary electron spectrum and the absorbed dose. Binding experiments were conducted to indirectly verify the results derived by MCNP6 and MCDS calculations. Results and Discussion: Damage yields of about 5.00×10^-4 were calculated for 100 bp aptamer due to the radiation dose of 1 Gy. In experiments with radioactive materials, the results that the removal rate of the radioactive ⁶⁰Co by the aptamer is the same with the non-radioactive ⁵⁹Co prove the accuracy of the previous DNA damage calculation. Conclusion: The evaluation results suggest that only very small fraction of significant number of the aptamers will be damaged by the radioactive materials in the liquid radioactive waste.

• 한국환경과학회지
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• 제31권12호
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• pp.1069-1078
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• 2022

This study investigated the weather conditions, fine particle concentration, and ion components in PM_2.5 when two cold fronts passed through Busan in succession on February 1 and 2, 2021. A analysis of the surface weather chart, AWS, and backward trajectory revealed that the first cold front passed through the Busan at 0900 LST on February 1, 2021, with the second cold front arriving at 0100 LST on February 2, 2021. According to the PM₁₀ concentration of the KMA, the timing of the cold front passage had a close relationship with the occurrence of the highest concentration of fine particles. The transport time of the cold front from Baengnyeongdo to Mt. Gudeok was approximately 11 hours . The PM₁₀ and PM_2.5 concentrations in Busan started to increase after the first cold front had passed, and the maximum concentration occurred two hours after the second cold front passed. The SO₄^2-, NO₃^-, and NH₄⁺ concentration in PM_2.5 started to increase from 1100 to 1200 LST on February 1, after the first cold front passed, and peaked at 0100 LST to 0300 LST on February 2. However, the highest Ca²⁺ concentration was recorded 2-3 hours after the second cold front had passed.