• Journal of Mechanical Science and Technology
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• v.20 no.9
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• pp.1475-1482
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• 2006

Wet compression means the injection of water droplets into the compressor of gas turbines. This method decreases the compression work and increases the turbine output by decreasing the compressor exit temperature through the evaporation of water droplets inside the compressor. Researches on wet compression, up to now, have been focused on the thermodynamic analysis of wet compression where the decrease in exit flow temperature and compression work is demonstrated. This paper provides thermodynamic and aerodynamic analysis on wet compression in a centrifugal compressor for a microturbine. The meanline dry compression performance analysis of centrifugal compressor is coupled with the thermodynamic equation of wet compression to get the meanline performance of wet compression. The most influencing parameter in the analysis is the evaporative rate of water droplets. It is found that the impeller exit flow temperature and compression work decreases as the evaporative rate increases. And the exit flow angle decreases as the evaporative rate increases.

• Environmental and Resource Economics Review
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• v.9 no.4
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• pp.621-639
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• 2000

High population and economic growth leads to ever increasing demand for water resources, prompting many regional conflicts for the water. With the observation, this paper examines the allocation problem of flowing water between upstream and downstream regions, We offer a two- region model in which the downstream region pays a portion of product to the upstream region in order to induce the upstream region to share the water. Our model shows that the "side-payment" does not always work, because the ex post income of the downstream region could be lower than the income without the side-payment This happens when the externality the upstream region imposes on the downstream region is small. The paper derives the condition under which the incentive mechanism like side-payment is likely to fail (or work). The model also shows that the higher the degree of externality is, the less amount of side-payment should be. The results of the paper suggest that the incentive scheme can help the regional conflicts be solved if the externality effect generated by the water use of upstream region is big enough, which is in fact the case where the conflict is severe.

• Journal of the Korean housing association
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• v.25 no.2
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• pp.37-44
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• 2014

The Gallery of Casa del Agua in Jeju Island was demolished by Jeju local government on March 6 in the last year. In the meanwhile, a lot of people including the architectural field had denied the demolition. Regardless of sustained efforts in order that the building could be preserved as a work, Jeju government ended up with demolishing the gallery. The Gallery of Casa del Agua was a temporary building constructed as a model house of Casa del Agua. As the remaining period of the temporary building had passed, it was on the verge of demolition by Jeju government. Casa del Agua is 'dwelling of water' in Korean, and the building was the last posthumous work of Mexican architect Ricardo Legorreta. Knowing from the expression of 'dwelling of water', this house is a dwelling work of him. Through this work, his architecture languages that he had pursued contained in dwelling could be looked into. This study examined the background and course of demolition of the Gallery of Casa del Agua, 'dwelling of water' and arranged problems in the course of demolition. Then, the fact that the Gallery of Casa del Agua as an architecture work of Ricardo Legorreta included his architecture languageswas analyzed. For this, his universalarchitecture languages were examined and how the architecture languages were applied to the Gallery of Casa del Agua was analyzed. As a result, it could be known that languages of composition and languages of emotion consistently shown in his works were represented in the Gallery of Casa del Agua.

• The Journal of Korea Robotics Society
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• v.15 no.1
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• pp.32-38
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• 2020

This paper describes a method for tracking attitude and position of underwater robots. Underwater work with underwater robots is subject to differences in work efficiency depending on the skill of the operator and the utilization of additional sensors. Therefore, this study developed an underwater robot that can operate autonomously and maintain a certain attitude when working underwater to reduce difference of work efficiency. The developed underwater robot uses 8 thrusters to control 6 degrees of freedom motion, IMU (Inertial Measurement Unit), DVL (Doppler Velocity Log) and PS (Pressure Sensor) to measure attitude and position. In addition, the thruster allocation algorithm was designed to follow the control desired value using 8 thrusters, and the motion control experiments were performed in the engineering water basin using the thruster allocation method.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.2
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• pp.21-32
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• 2005

Questionnaire survey from 101 visitors and 77 specialists was carried out to establish the management plan on landscapes of the artificial structure constructed in valley within Bughansan National Park. When comparison was made between ground sill work structure and valley landscape, visitor group responded to the highest scores in valley landscape after planting of vine species in the bottom of the constructure, while specialist group responded to valley landscape after the removal of the constructure. When it made a comparison between revetment work constructure and valley landscape, visitor group responded to highest scores in valley landscape after planting of vine species in the top of the constructure, while specialist group responded to valley landscape after replacing concrete revetment by stone revetment constructure. When it made a comparison between fall work constructure and valley landscape, both groups responded to the highest scores in valley landscape after the removal of the constructure. According to the valley landscape analysis, artificial constructures built in water channel should be matched to adjacent landscape with the removal of concrete constructure. The slope of water channel should be considered to build fall work constructure.

• Journal of Power System Engineering
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• v.17 no.6
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• pp.102-107
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• 2013

In this paper, the performance analysis for evaporation capacity, total work and efficiency of the ocean thermal energy conversion(OTEC) power system using mixed refrigerant(R32,R152a) is conducted to find the effect of hot wasted water on OTEC power system. The system in this study is applied with two stage turbine, regenerator, cooler and separator on Organic Rankine Cycle. The commercial program HYSYS is used for the performance analysis. The main results were summarized as follows : The efficiency of the OTEC power cycle has a largely effect on the evaporation capacity and total work. As increasing temperature of heat source water, evaporator's capacity is decreased but total work increase. Otherwise, using hot wasted water bring effects not only increasing system efficiency but also declining evaporator's capacity. Thus With a thorough grasp of these effect, it is necessary to find way to use hot wasted water emitted by power plant and so on.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.827-832
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• 2009

Exergy is the amount of reversible work obtainable when some matter is brought to a state of thermodynamic equilibrium with ambient. This exergy is availability or useful work induced from carnot cycle, and this can calculate the irreversible loss work which occurs within any thermal or power cycle. The exergy ratio is the value of exergy divided by enthalpy of ambient reference, where the quality of energy or enthalpy in substances is evaluated by exergy ratio. Exergy is very important in optimal design method of thermal system or each component, and the value of exergy at given state is calculated by equation. Here, designer can easily understand and find the value of enthalpy because enthalpy is graphically drawn in chart, however exergy did not. In this paper, exergy and exergy ratio of air were drawn on temperature-entropy chart, and we wish to this chart is a help to design, analysis and education.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.2
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• pp.111-120
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• 2000

Water, waste, electric and gas facilities are urban based facilities that needed in our life and are often located in underground. Therefore, underground facilities are more difficult to manage efficiently than ground facilities. It is needed to carry out survey/probe into underground facilities and to build database in order to prevent city-misfortunes being occurred because of negligent management and in order to minimize budget-waste and a traffic jam according to repetition of road excavation constructions. Also, the development of application system is required to manage efficiently underground facility. Chonju city has launched underground water supply facility computerizing project as a part of National Geographic Information System project until December 1998 and executed survey/probe into 402.89 km water supply that is 80 mm up inside central town area 39.6 $km^2$. Also, chonju city built database into 537 km water supply that is 80 mm below based on water supply card without other survey/probe works. Also, existing work process each department is changed into GIS applied work process and underground water supply facility management system is developed by its work process basis. Water supply underground facility management system that is developed is composed of sub-system like base-map management, water supply inspect, water supply management and water supply inquiry, construction work management, administration management and map management. This research presents the procedure and method of underground water supply facility survey/probe and problem being occurred during survey/probe procedure and also show the functions of each sub-systems composing underground water supply facility management system.

• Journal of the Korean Institute of Gas
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• v.28 no.1
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• pp.27-34
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• 2024

In accordance with the clean hydrogen-centered hydrogen industry development plan, technology development and demonstration operation of water electrolysis devices are being actively carried out. Risk assessments are performed on newly developed hydrogen-using facilities and supplies to identify potential hazard factors. However, in general, most industrial accidents are caused by operator's human error or incorrect work practices. Additionally, the possibility of accidents occurring during operation control, maintenance, and inspection increases. For this reason, for equipment developed for demonstration operation, the correct work methods for the main jobs of operator must be reviewed and work procedures must be prepared. Accordingly, in this study, we conducted a job safety analysis (JSA) on major jobs in the operation of water electrolysis facilities to study safe work methods and necessary measures.

• Journal of Industrial Convergence
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• v.22 no.1
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• pp.85-93
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• 2024

The purpose of this study was to examine the relationship between high-intensity physical activity (work) and beverage intake frequency among Koreans. The data used in this study were obtained from the 8th Korea National Health and Nutrition Examination Survey(KNHANES) conducted in 2021. Statistical analyses, including χ²-test, and binary logistic regression, were conducted to examine group differences(p<0.05). It was found that 63.6% of the group consumed carbonated water once a week or less, and 68.6% consumed energy drinks once a week or less. These results indicated that carbonated water and energy drinks were more frequently consumed among individuals engaging in high-intensity physical activity(work), and that the majority of beverages were consumed once a week or less. Based on the findings of this study, it was hoped that the results can serve as a basis for the development of healthier alternative beverages to replace carbonated water and energy drinks during high-intensity physical activity(work). Additionally, it highlights the importance of exploring new approaches that promote health and the need for intervention programs aimed at improving health.