• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.1
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• pp.55-64
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• 1995

This paper presents analytic results of energy sequestered for the forcing cultural Cu- cumber and the others production system with the input-output tables method in the suthern parts of Korea. In this study an attempt is made to evaluate input of direct and indirect energy, output of yield energy and net energy in order to achieve increased energy productivity under P E greenhouse. Cultural practices were grouped soil and soilless with perlite for vegetable production. The results from this study are summarized as follows : 1. Total energy inputs in cucumber production were calculated to be 510 GJ/l0a(di- rect energy : 480 GJ/lOa, indirect energy : 30 GJ/lOa) from soil culture and 440 GJ/ 10a(direct energy : 420 GJ/lOa, indirect energy : 20 GJ/lOa) from soilless culture in perlite hydroponics. 2. Energy outputs from cucumber and biomass were 7 GJ/lOa and 120 GJ/lOa at a uniform rate respectively. 3. Heating fuel as diesel is a major energy inputs approaching 90% of the total energy requirements for cucumber production. 4. Net energy in cucumber production was calculated to be 503 GJ/lOa from soil cul- ture and 431 GJ/lOa from soilless culture. Net energy productivity was maintained costantly as 0.98. 5. Energy productivity in cucumber was calculated to be 0.029 kg/MJ from soil culture and 0.043kg/MJ from soilless culture, while energy efficiency was 0.012 and 0.015 respectively. It is expected that a soilless cultural production system seems to be reduc- tive in seguestered energy input by 13%.

• Journal of Environmental Science International
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• v.18 no.2
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• pp.187-195
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• 2009

This study was investigated to control the corrosion and scale at the cooling water system in steel works. Laboratory and field tests were performed for the indirect cooling water system of plate mill. Throughout the experiment, various factors such as leakage of pipes, heating rate and capacity, and the reaction between existing and substitute inhibitors were carefully monitored. The results showed that the harmful effect of high temperature could be minimized, and satisfactory corrosion/scale controls were effectively achieved using inhibitor, even at the increased temperature of $80^{\circ}C$. The batch and field tests in the gas scrubbing cooling water system of blast furnace and cooling water system of corex plant indicated that the new inhibitor was more effective for the prevention of corrosion and scale than the existing one.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.06a
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• pp.93-98
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• 2006

Warm forming technology was classified into hot gas forming of using compressible fluid as a nitrogen gas and warm hydroforming of using the incompressible fluid as a thermal oil by using medium fluid. In this study, the aluminum side-rail part was developed with warm hydroforming technology. For the warm hydroforming system, top and bottom die was designed to insert heating cartridge in die cavity and special indirect fluid heating system was designed to heat the thermal oil. As increase the temperature, hydroformability was increased linearly. Aluminum side-rail center part was formed 90% at the internal pressure of 100bar and perfectly formed at 300bar within a moderate temperature. The tube material used for warm hydroforming was a aluminum 6000 series alloy with the diameter of 120mm, thickness of 5mm, length of 1,300mm. Warm hydroformed side-rail center part had 20% of maximum expansion ratio and below 20% of maximum thinning ratio at corner radius. This results were provided to show warm hydroforming possibility for aluminum automotive components.

• Proceedings of the Korean Environmental Health Society Conference
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• 2002.04a
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• pp.84-90
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• 2002

In 1995 we licensed pyrolysis gas melting technology of indirect heating type (using kiln) from Siemens AG, and built its demonstration facility in 1998 at Clean-Park-East of Fukuoka City to demonstrate the technology for municipal solid waste (MSW). In 1997 we were awarded an order from Kanemura Co., Ltd. to build a pyrolysis gas melting and power generation plant, specifically for treating residue from car shredder. The latter was launched in 1998, and is currently in commercial operation. The operation of these plants have proven the following facts. (1) The system is capable for performing a stable operation with a wide variety of waste. (2) Pyrolysis is achieved steadily regardless of the variation in the quality of waste. (3) The system can be operated under low excess air ratio (1.2∼1.3). (4) The concentration of dioxins at the furnace outlet is 0.062ng-TEQ/㎥$\_$N/, and 0.002ng-TEQ/㎥$\_$N/, at the stack. (the value is corrected to dryO$_2$ 12％) (5) The purity of recovered metals exceeds 90%.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.4
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• pp.531-536
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• 2016

The worldwide research and development for high-efficiency power generation system is progressing steadily because of the growing demand for reducing greenhouse gas emissions. Many countries have spurred the research and development of supercritical $CO_2$ power generation technology since 2000 because it has the advantage of compactness, efficiency, and diversity. Supercritical $CO_2$ power generation system can be classified into an indirect heating type and a direct heating type. As of now, most studies have concentrated on the development of indirect type supercritical $CO_2$ power generation system. In the United States, NREL(National Renewable Energy Lab.) is developing supercritical $CO_2$ power generation system for Concentrating Solar Power. In addition, U.S. DOE(Department of Energy) also plans to start investing in the development of the supercritical $CO_2$ power generation system for coal-fired thermal power plant this year. GE is developing not only 10MW supercritical $CO_2$ power generation turbomachinery but also the conceptual design of 50MW and 450MW supercritical $CO_2$ power generation turbomachinery. In Korea, the Korean Atomic Energy Research Institute has constructed the supercritical $CO_2$ power generation test facility. Moreover, KEPRI(Korea Electric Power Research Institute) is developing a 2MW-class supercritical $CO_2$ power generation system using diesel and gas engine waste heat with Hyundai Heavy Industries.

• Journal of the Speleological Society of Korea
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• no.85
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• pp.1-14
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• 2008

Electroluminescent Display(ELD) will be the innovative ideas to replace existed electricity illumination systems that consider to under effectiveness and environmental pollution generators in the commercial caves because ELD has less heat and low electricity consumption by the new illumination materials. Characteristics of the ELD are as following: it is a proper matter for the small merchandise ads due to its thickness is only below 3oo micoron, electricity consumption of ELD is less (1/3) than LED, ELD that is a whole face illumination system is much brighter than LED that is a dot illumination system, ELD is longer life than others due to its less light generation systems, ELD is any problems to bend, and it is a best device to use a light board ads. ELD has advantages on conservation of cave biosystems and reduce pollution when ELD is installed in touring spots and emergency corridors of weak illuminated cave internal areas by less heating and low electricity consumption using the indirect illumination of the ELD. Therefore when the high technologic ELD is installed in the commercial caves in Korea, it will be innovating cave environmental systems, saving budgets, and increasing tours.

• Journal of Aerospace System Engineering
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• v.10 no.2
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• pp.41-45
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• 2016

Statistical data show that a large aircraft(transport category) is struck by lightning once a year or once per 1,000 ~ 20,000 flight time. The protection design for lightning must be applied to the aircraft because an aircraft is developed on condition that it is absolutely struck by lightning. For the proper protection design, we need to understand direct effect and indirect effect of lightning. This paper described the direct effect of lightning on aircraft's structures and systems.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.19-22
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• 2003

In this paper are described the indirect induction heated boiler and induction heated hot air producer using the voltage-fed series resonant high-frequency inverter which can operate in the frequency range from 20 [kHz] to 50 [kHz]. A specially designed induction heater, which is composed of laminated stainless assembly with many tiny holes and interconnected spot welding points between stainless plates, is inserted into the ceramic type vessel with external working coil. This working coil is connected to the inverter and turbulence fluid through this induction heater to moving fluid generates in the vessel. The operating performances of this unique appliance in next generation and its effectiveness are evaluated and discussed from a practical point of view.

• Solar Energy
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• v.2 no.2
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• pp.29-36
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• 1982

The Solar Energy R&D Department of KIER under the auspice of the Korean government is pushing hard on the development of the passive solar technology with high priority for the expeditious widespread use of solar energy in Korea, since the past few years of experiences told us that the active solar technology is not yet ready for massive commercialization in Korea. KIER has completed the construction of the Solar Energy Research & Test Center in Seoul, which houses the major facilities for its all solar test programs. The Center was designed as a passive solar building with great emphasis on the energy conserving ideas. The Center is not only the largest passive building in Korea, but also the exhibit center for the effective demonstration of the passive heating and cooling technology to the Korean public. The Center was designed to satisfy the requirements based on the technical and economical criteria set by the KIER. Careful considerations, therefore, were given in depth in the following areas to meet the requirements. 1) Passive Heating Concepts The Center employed the combination of direct and indirect gain system. The shape of the Center is Balcomb House style, and it included a large built-in sunspace in front. A partition, consists of transparent and translucent glazings, separates the sunspace and the living space. Since most activities in the Center occur during the day time, direct utilization of the solar energy by the living spaces was emphasized with the limited energy storage capacity. 2) Passive Cooling Concepts(for Summer) Natural ventilation concept was utilized throughout the building. In the direct gain portion of the system, the front glazing can be openable during the cooling season. Natural convection scheme was also applied to the front sunspace for the Summer cooling. Reflective surfaces and curtains were utilized wherever needed. 3) Auxiliary Heat ing and Cooling System As an auxiliary cooling system, mechanical means(forced convection system) were adopted. Therefore forced air heating system was also used to match the duct work requirements of the auxiliary cool ing system. 4) Effect ive Insulation & Others These included the double glazed windows, the double entry doors, the night glazing insulation, the front glazing-frame insulation as well as the building skin insulation. All locally available construction materials were used, and natural lightings were provided as much as possible. The expected annual energy savings (compared to the non-insulated conventional building)of the Center was estimated to be about 80%, which accounts for both the energy conservation and the solar energy source. The Center is being instumented for the actual performance tests. The experimental results of the simplified tests are discussed in this paper.

• Journal of the Korean Home Economics Association
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• v.18 no.1
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• pp.67-82
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• 1980

The objectives of the study were to determine 1) energy uses for residential requirements, 2) if energy consumption and adoption of energy conservation attitudes and practices vary with independent variables family size, stage of family life cycle, homemaker's level of education, income, heating system, and number of electrical household items, and 3) if there is a correlation between energy conservation attitudes and practices. Questionnaires were given to the randomly selected homemakers I Seoul in the summer (September, 1979) and the winter (February, 1980). Analysis of variance and correlation were used to analyzed the data which consisted of 537 usable responses of 895 returned in the summer and 554 responses of 794 returned in the winter. The results are as follows: 1) The order of consumption rate of the direct energy uses for residential requirements was found to be heating and air conditioning, cooking, refrigeration, T.V., lighting, and miscellaneous. 2) Energy consumption and adoption of energy conservation attitudes and practices were significantly related to family size, homemaker's level of education, and the stage of family life cycle. (1) Families of five members revealed higher scores in attitudes and practices than families less than five or more than six. (2) The higher the homemaker's level of education, the more energy consumption and the higher scores I attitudes and practices were found. (3) Families in the middle stage of family life cycle tend to use more energy than younger or older families, but their scores in attitudes and practices were high. 3) There was a significant correlation between energy conservation attitudes and practices. However, the scores of the conservation practices were not as good as the attitudes. It may be attributed to either a lack of knowledge and/or financial difficulties, or a dissonance between the concept and implementation of energy conservation. 4) Recommendations for the energy-saving and energy-related public policies are: (1) to use such human resources as attitudes, values, feelings of agreement, and cooperation, as well as nonhuman resources for the energy conservation, (2) to develop a educational program and a creative system I order to implement energy conservation programs, and (3) to consider direct as well as indirect energy uses I selecting goods and services.