• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.566-574
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• 2011

Coal gasifier is a key component for achieving high efficiency in integrated gasification combined cycle and indirect coal liquefaction. Although there have been several successful coal gasifiers that were commercially proven, many different design configurations are still possible for a simple and reliable gasifier operation. Four different gasifier design concepts of dry-feeding were compared in terms of residence time, exit syngas temperature and syngas composition. First, cold-flow simulation was applied to pre-select the configuration concepts, and the hot-flow simulation including chemical reactions was performed to compare the concepts at more actual gasifier operating conditions. There are many limitations in applying CFD method in gasifier design, particularly in estimating slag behavior and slag-tap design. However, the CFD analysis proved to be useful in comparing the widely different gasifier design concepts as a pre-selection tool.

• Archives of Craniofacial Surgery
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• v.21 no.6
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• pp.376-379
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• 2020

Supraclavicular lymph node (SCLN) flap is a common donor site for vascularized lymph node transfer for the treatment of lymphedema. Chyle leakage is a rare but serious complication after harvesting SCLN flap in the neck. We report a case of chyle leakage at the SCLN donor site and its successful management. A 52-year-old woman underwent SCLN transfer for treatment of lower extremity lymphedema. After starting a regular diet and wheelchair ambulation on the 3rd postoperative day, the amount of drainage at the donor site increased (8-62 mL/day) with the color becoming milky, which suggested a chyle leak. Despite starting a low-fat diet on the 4th postoperative day, the chyle leakage persisted (70 mL/day). The patient was started on fat-free diet on the 5th postoperative day. The amount of drainage started to decrease and the drain color became more clear within 24 hours. The drainage amount remained less than 10 mL/day from the 8th postoperative day, and we removed the drain on the 12th postoperative day. There was no seroma or other wound complications at follow-up 4 weeks after the operation. The current case demonstrates that a fat-free diet can be a first-line treatment for low output chyle leakage after a SCLN flap.

• Journal of Advanced Navigation Technology
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• v.25 no.3
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• pp.177-184
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• 2021

This paper proposes an assessment method using probability-based index for safe and successful underwater docking of autonomous underwater vehicles(AUVs) to the docking stations(DSs). The proposed method assesses the probability of docking according to the degree to which the state of the AUV is consistent with the state criteria for docking. The assessment is performed within a specific area considering the kinematic constraints and docking plans of the AUV. The assessment process is defining probability density function, calculating probabilities for reaching the docking station according to the difference to position and heading criteria, and computing the probability-based index in real-time. We verify the validity of the proposed method through analyzing the data acquired on operation test.

• The Journal of the Convergence on Culture Technology
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• v.7 no.1
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• pp.202-210
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• 2021

The purpose of this study is to analyze the mediating effect of job-stress in relation to the leadership competency and job-satisfaction of the childcare center principal. This study was to conducted using questionnaires on 212 childcare center principals located in G city and collected data were analyzed using SPSS/PC 21.0. The study results were as follows. First, leadership competency of the childcare center principal showed higher than average degree and job-satisfaction and job-stress showed average degree. Second, there were statistically significant positive correlation between the leadership competency and job-satisfaction of the childcare center principal. And job-stress showed statistically significant negative correlation with leadership competency and job-satisfaction of the childcare center principal. Third, the leadership competency of the childcare center principal affects job satisfaction, and job stress has a partial mediating effect between leadership competency an job satisfaction. For the successful operation of the childcare center, it is necessary to find a variety of policy and institutional measures to reduce job stress of principal of childcare center and increase job satisfaction to demonstrate positive leadership competency.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.1-12
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• 2021

The International Maritime Organization (IMO) is promoting the introduction of e-Navigation that prevents maritime accidents by fusion of Information & Communication Technology (ICT) with ship operation technology. In Korea, Korean e-Navigation is also being developed for fishing vessels and small vessels sailing offshore, which are vulnerable to maritime accidents. However, for the successful development of Korean e-Navigation, it is necessary to develop an indicator that can evaluate the development performance so that the development performance that has been progressed so far can be evaluated and the development direction can be re-established. Therefore, this study attempted to develop an evaluation index tailored to the development goal of e-Navigation service centering on the collision accident, which is a major maritime accident. In this study, a collision accident evaluation index for e-Navigation service was developed by deriving and quantifying the root cause of maritime collision accidents using Root cause analysis(RCA) and fault tree analysis (FTA) techniques. This indicator is considered to be helpful in reducing maritime accidents as it is used as a development indicator for e-Navigation and an indicator for maritime collision accident analysis.

• Korean Journal of Clinical Pharmacy
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• v.31 no.1
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• pp.53-60
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• 2021

Objective: To gather the opinions of hands-on workers for successful introduction of the Development Safety Update Report (DSUR) according to a five-year comprehensive plan for clinical trial development [Ministry of Food and Drug Safety, 2019]. Methods: We conducted a survey on considerations that industry stakeholders may have related to the enforcement of the DSUR. A questionnaire was distributed among pharmacovigilance specialists from 13 pharmaceutical companies in South Korea on June 4, 2020. The questionnaire comprised two sections: 1) current status of the Drug Safety Data Management System and 2) considerations on the implementation and management of the DSUR. Results: All respondents have agreed the introduction of DSUR is inevitable for regulatory harmonization and safety of trial subject. However, most respondents (85%) felt concern about additional workload with DSUR implementation. They answered that format and operation system of DSUR should be harmonized with those of international standards and authorities need to minimize double burden due to related report. Conclusion: All respondents asserted that domestic DSUR should be harmonized with International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) E2F guidelines. Respondents from global companies also suggested regulatory authorities allow DSUR written in English to replace Korean version considering their deadline for submission. Moreover, every respondent agreed regulatory authorities need delicate effort when implementing mandatory submission of DSUR to ensure that even small pharmaceutical companies with no experience in DSUR can comply with the system.

• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.3
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• pp.89-100
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• 2021

This paper deals with the construction of a combustion test facility and preliminary tests for hot-firing tests of a methane engine. First, the combustion test facility for a 1 kN-class thrust chamber using liquid oxygen/gas methane as propellants was designed and built. Before hot-firing tests, the cold-flow tests of each propellant line and the ignition tests of torch igniter/afterburner were performed to verify propellant supply stability of the combustion test facility, operation of the control and measurement system, and successful ignition. Finally, a preliminary hot-firing test was conducted to measure the combustion efficiency, heat flux, and combustion stability of a thrust chamber prototype. The constructed combustion test facility will be helpfully used for basic research and development of methane engine thrust chambers.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.3
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• pp.412-421
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• 2022

All 5G NR devices must first perform the cell search and synchronization process to communicate with the base station. In this process, PSS detection is one of the most important and difficult problems in 5G NR communication because PSS detection must first be successful in order to extract essential information from the following signals. Among the various PSS detection methods, this paper describes a cross-correlation-based detection method, and the implementation methods of the tap delay line hardware with parallelization are introduced and compared in terms of complexity and detection speed. In addition, the interface required for system configuration including the PSS detector and control software for efficient and flexible operation are also explained. In this paper, the resource usages of Xilinx's UltraScale+ FPGA are compared for various PSS detector structures and analyzed according to various parallelization levels.

• The Journal of Engineering Geology
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• v.31 no.4
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• pp.549-559
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• 2021

The Arctic Circle's huge amounts of fossil fuels and mineral resources are being developed and subjected to active construction projects. Global efforts are continuing to actively respond to climate change, but the dependence on fossil fuels remains high. This study reports a preliminary survey conducted in Alberta, Canada, where oil sand resources are actively developed. A land cover map was prepared using satellite imagery to reduce the cost and time of surveying a wide area. Results likely useful to resource development projects such as ground surface temperature and snow cover distribution were derived by using the obtained image classification results. It is expected that the results of the present research and analysis will be used to establish strategies for the successful promotion and operation of projects to develop resources in the Arctic.

• Journal of People, Plants, and Environment
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• v.23 no.6
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• pp.589-602
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• 2020

Background and objective: There are many theories related to the development of agrotourism, and each stakeholder has its own role and function. If it is based on organizational functions, stakeholders need to be coordinated, and the state plays a major administrative role. But in the successful case of Yeongdong County, Chungcheongbuk province, the Republic of Korea, the government played an important role in the development of tourism, which grants us another perspective on the role of the government in promotion and development agrotourism activities. Methods: This article aims to examine the development of agrotourism through a cooperative approach, by clarifying the role of the local authorities in the Yeongdong region in the management and operation of the local agrotourism activities. The qualitative research method is based on a field survey conducted in Yeongdong County in 2019. Results: The study's findings show that in situations where conflicts of interest among stakeholders are prone to occur, the development of local tourism has a limited impact on the cooperative culture, and local governments play an important role. Accordingly, the local governments must actively formulate strategies to maintain and develop traditional agricultural industries and at the same time develop agrotourism activities. The government's ability to coordinate, cooperate, and participate reasonably is a key factor for the success of the sustainable development of the tourism industry. Conclusion: Based on coordination between stakeholders and a reasonable strategic direction, Yeongdong's agrotourism is being effectively deployed. The development of Yeongdong's agrotourism industry has achieved impressive results through an effective strategy, highlighting the important role of localgovernment in the consensus of local communities and collaboration with stakeholders. The role of outstanding local governments has been clearly demonstrated, especially in promoting, establishing, and contacting different organizations to effectively deploy agrotourism in the region.