• Nuclear Engineering and Technology
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• v.39 no.1
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• pp.1-8
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• 2007

Hydrogen and electricity are expected to dominate the world energy system in the long term. The world currently consumes about 50 million metric tons of hydrogen per year, with the bulk of it being consumed by the chemical and refining industries. The demand for hydrogen is expected to increase, especially if the U.S. and other countries shift their energy usage towards a hydrogen economy, with hydrogen consumed as an energy commodity by the transportation, residential and commercial sectors. However, there is strong motivation to not use fossil fuels in the future as a feedstock for hydrogen production, because the greenhouse gas carbon dioxide is a byproduct and fossil fuel prices are expected to increase significantly. An advanced reactor technology receiving considerable international interest for both electricity and hydrogen production, is the modular helium reactor (MHR), which is a passively safe concept that has evolved from earlier high-temperature gas-cooled reactor (HTGR) designs. For hydrogen production, this concept is referred to as the H2-MHR. Two different hydrogen production technologies are being investigated for the H2-MHR; an advanced sulfur-iodine (SI) thermochemical water splitting process and high-temperature electrolysis (HTE). This paper describes pre-conceptual design descriptions and economic evaluations of full-scale, nth-of-a-kind SI-Based and HTE-Based H2-MHR plants. Hydrogen production costs for both types of plants are estimated to be approximately $2 per kilogram.

• The Korean Journal of Emergency Medical Services
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• v.23 no.1
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• pp.125-134
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• 2019

Purpose: The aim of this study was to evaluate the usefulness of video communication with medical staff located at a remote location, through a communication application connected to a long term evolution (LTE) mobile communication network in a moving ambulance. Methods: In this study, we recruited patients who were transferred by mobile intensive care unit ambulance from one hospital to another. In the moving ambulance, the information of the patient was transferred to a physician using the application in real time. Recorded video files were evaluated by emergency physicians with experience in video direct medical control. Results: A total of 18 patients were evaluated, and the average score was 5.9 out of a possible 9. It was expected that applying the use of the technology to actual clinical sites would enable the sites to provide assistance. Conclusion: In this study, we confirmed the possibility of benefiting from the clinical field when using the video-audio communication application which is connected to the remote location in real time through the current LTE mobile communication network in the ambulance.

• Journal of Navigation and Port Research
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• v.46 no.5
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• pp.449-457
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• 2022

The Port of Busan is currently ranked as the seventh largest container port worldwide in terms of cargo throughput. However, port competition in the Far-East region is fierce. The growth rate of container throughput handled by the port of Busan has recently slowed down. In this study, we analyzed how economic conditions and multiple external shocks could influence cargo throughput and identified potential implications for port business. The aim of this study was to build a model to accurately forecast port throughput using the ARIMA model, which could incorporate external socio-economic shocks, and the VEC model considering causal variables having long-term effects on transshipment cargo. Findings of this study suggest that there are three main areas affecting container throughput in the port of Busan, namely the Russia-Ukraine war, the increased competition for transshipment cargo of Chinese ports, and the weaker growth rate of the Korean economy. Based on the forecast, in order for the Port of the Port of Busan to continue to grow as a logistics hub in Northeast-Asia, policy intervention is necessary to diversify the demand for transshipment cargo and maximize benefits of planned infrastructural investments.

• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.127-134
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• 2022

Scholars and companies have made a lot of effort to increase customer loyalty to achieve long-term customer retention and sustainable profitability. The author proposes a conceptual model with the purpose of understanding the antecedent variables which have impact on customer attitudinal/behavioral loyalty. In addition, this article examines the mediating effects of perceived value between self-congruity and customer loyalty. The results show that self-congruity has significant, direct, and positive effects on perceived value and customer loyalty. Meanwhile, self-congruity indirectly affects attitudinal and behavioral loyalty, that is, the mediating effects of perceived value are significant. The author proposes the implications of these findings for practitioners and related industries.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.380-387
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• 2009

In the past, many state Departments of Transportation (DOTs) in the U.S. managed their highway assets on a "worst first" basis and planned their highway projects in a tactical rather than strategic fashion. Due to increasingly tight highway budgets and recognition of long term benefits of asset management systems, the Federal Highway Administration (FHWA) has strongly pushed and encouraged state DOTs to implement asset management for managing their highway assets and highway projects. Currently, many DOTs have actively implemented and are in the process of applying this asset management concept for their highway infrastructure. However, different DOTs are developing different asset management systems because of their different organizational structures, data management structures, relationship with the legislature, and investment priorities. This study first identifies asset management indicators which are essential to successfully implementing asset management systems for State highway assets. The research team conducted a survey of asset management experts and reviewed the practices and policies of leading DOTs in asset management. Based on these indicators, this study develops an Asset Management Assessment Model (AM²) for different asset management systems. This model can be used by different DOTs to evaluate their current asset management systems and identify their strong areas and also their weak areas to improve in order to fully benefit from the advanced concept of asset management.

• Journal of Wellbeing Management and Applied Psychology
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• v.6 no.4
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• pp.63-68
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• 2023

Purpose: This study aims to investigate the national obligation of public health support for residents in medically vulnerable areas in Korea, and to propose a suitable model for public health institutions in this region. Research design, data, and methodology: A survey targeting residents was conducted from August 10 to August 17, 2021, with a sample size of 177 general citizens. The survey utilized a structured questionnaire administered online through Google, employing convenience random sampling. After an editing process to ensure data accuracy, the final dataset of 174 valid samples underwent encoding, coding, and cleaning using the IBM SPSS Statistics 22.0 program for analysis. Results: Health status revealed a moderate level, and 63.8% reported having chronic diseases, particularly prevalent among the elderly. External healthcare institutions were commonly utilized, with proximity and competence of doctors being primary reasons. Respondents expressed a need for improving the public health and medical system, emphasizing the establishment of a County Health Centre and expanding medical departments. Conclusions: In this region, the region's unique challenges, including education, employment, population decline, aging, and transportation, require multidimensional efforts and urgent intervention by public entities. Long-term strategies involve considering the establishment of a health and medical institute, adjusting health centre resources to local realities, and fostering a cooperative system for collaboration among residents and institutions.

• Journal of Korean Society of Transportation
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• v.32 no.2
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• pp.93-105
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• 2014

This study evaluated the relative efficiency of mobile emission reduction countermeasures through a Data Envelopment Analysis (DEA) approach and determined the priority of countermeasures based on the efficiency. Ten countermeasures currently applied for reducing greenhouse gases and air pollution materials were selected to make a scenario for evaluation. The reduction volumes of four air pollution materials(CO, HC, NOX, PM) and three greenhouse gases($CO_2$, $CH_4$, $N_2O$) for the year 2027, which is the last target year, were calculated by utilizing both a travel demand forecasting model and variable composite emission factors with respect to future travel patterns. To estimate the relative effectiveness of reduction countermeasures, this study performed a super-efficiency analysis among the Data Envelopment Analysis models. It was found that expanding the participation in self car-free day program was the most superior reduction measurement with 1.879 efficiency points, followed by expansion of exclusive bus lanes and promotion of CNG hybrid bus diffusion. The results of this study do not represent the absolute data for prioritizing reduction countermeasures for mobile greenhouse gases and air pollution materials. However, in terms of presenting the direction for establishing reduction countermeasures, this study may contribute to policy selection for mobile emission reduction measures and the establishment of systematic mid- and long-term reduction measures.

• Clean Technology
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• v.18 no.1
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• pp.69-75
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• 2012

In this study, we executed an environmental impact assessment about recycling of ITO (Indium Tin Oxide), used for touch panel. ITO is mainly used to make transparent conductive coatings for touch and flat screen LCD (Liquid Crystal Display), ELD (Emitting Light Device), PDP (Plasma Display Panel). This demand is increasing little by little. but form current status, ITO is discarded than recycling. It is important to recycling ITO for national strategies about resource conservation, and reduce environmental burden. Also Landfill or incineration of ITO cloud be harmful to the human health in the long-term. Material Life Cycle Assessment method (MLCA) was conducted for comparison landfill and recycling of ITO. MLCA would provide more information for environmental issues and potential environmental impacts of ITO. The study includes two scenarios, the basic scenario is recycling of ITO (10, 20, 30%) and the other scenario is landfill of ITO. In addition, amount of carbon dioxide and energy were calculated.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.434-441
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• 2010

'Wonhwang' pear ($Pyrus$ $pyrifolia$ Nakai) often showed physiological disorder and quality deterioration during long-term storage and shelf life although this cultivar has the advantage of a good appearance and better taste for overseas exportation. This study was conducted to investigate the effect of temperature during transportation and continuing market temperature on fruit quality, and the occurrence of physiological disorder to set up the appropriate transportation and distribution temperatures in the fruits harvested at different times. Unripe fruits harvested 120 days after full bloom maintained higher firmness until 21days of shelf life at both 18 and $25^{\circ}C$ than late harvested ones. Otherwise, ripe fruits harvested 130 days after full bloom showed high incidence of mealiness breakdown of flesh tissues in 21 days of shelf-life at $25^{\circ}C$ of market temperature, but not in the fruits stored at $18^{\circ}C$. Late harvested fruits showed much severe physiological disorders when compared with early harvested ones that showed relatively lower respiration rates. Fruit quality parameters were more highly affected by market temperature than transportation temperature. Results showed that unripe fruits harvested at 120 days after full bloom maintains high marketability until 21 days of shelf-life, while the maximum shelf-life of ripe fruits harvested 130 days after full bloom will be considered at within 7 days.

• Geomechanics and Engineering
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• v.32 no.1
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• pp.111-123
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• 2023

The slope of an open cut tunnel is located above the exit of the Leijia tunnel on the Changgan high-speed railway. During the excavation of the open cut tunnel foundation pit, the slope slipped twice, a large landslide of 92500 m³ formed. The landslide body and unstable slope body not only caused the foundation pit of the open cut tunnel to be buried and the anchor piles to be damaged but also directly threatened the operational safety of the later high-speed railway. Therefore, to study the stability change in the slope of the open cut tunnel under heavy rain and excavation conditions, a 3D numerical calculation model of the slope is carried out by Midas GTS software, the deformation mechanism is analyzed, anti-sliding measures are proposed, and the effectiveness of the anti-sliding measures is analyzed according to the field monitoring results. The results show that when rainfall occurs, rainwater collects in the open cut tunnel area, resulting in a transient saturation zone on the slope on the right side of the open cut tunnel, which reduces the shear strength of the slope soil; the excavation at the slope toe reduces the anti-sliding capacity of the slope toe. Under the combined action of excavation and rainfall, when the soil above the top of the anchor pile is excavated, two potential sliding surfaces are bounded by the top of the excavation area, and the shear outlet is located at the top of the anchor pile. After the excavation of the open cut tunnel, the potential sliding surface is mainly concentrated at the lower part of the downhill area, and the shear outlet moves down to the bottom of the open cut tunnel. Based on the deformation characteristics and the failure mechanism of the landslides, comprehensive control measures, including interim emergency mitigation measures and long-term mitigation measures, are proposed. The field monitoring results further verify the accuracy of the anti-sliding mechanism analysis and the effectiveness of anti-sliding measures.