• Journal of Information Technology Applications and Management
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• v.24 no.4
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• pp.25-39
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• 2017

This research conducted empirical and comparative study following interview concerning the relationship of acceptance attitudes and expected effects of the teleworking between Korean and Canada organizations. Independent variable was acceptance attitude, and the expected effect as dependent variable. Totally, 201 responded questionnaires (Korea : 118, Canada : 83) were analyzed for multiple regression and mean difference between groups. On January 1, 2015, Canada had agreed FTA (free trade agreement) with Korea. Therefore, many organizations can have opportunities for sharing hands in social infrastructures and business area. As a result, the research found out that teleworking can positively improve employee's quality of life, efficiency of works. Moreover, respondents informed us that it may give us national and social cost saving. The BYOD (bring your own device) will be helpful to make employees do more active communication. This comparative research expects that two countries have some insights to cooperate in smart work or teleworking. In addition, several Korean companies can have chances to export IT technologies to Canada market.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.5
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• pp.212-217
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• 2014

Recently, the use of renewable energy has been increased due to growing concern on the energy-saving at buildings and the reduction of $CO_2$ emission. In the field of architecture, to reduce the energy consumption of heating, cooling and hot water supply, heat pump systems with renewable energy has been developed and used in various applications. However, there have been many of researches on the large-scale commercial heat pump systems, but the research and the field application of a compact heat pump system is rare. Therefore, in order to develop the compact heat pump for the small-scale residential building, this study conducted the performance test and feasibility study for a hybrid heat pump using the heat source of air, solar and ground. In the results of experiments through a trial product, the average COP of cooling mode with ground heat source was 4.75, and it of heating mode was 4.03. Furthermore, the average COP of cooling mode with air heat source was 2.60, and it of heating mode was 2.92. Finally, payback period of the system was calculated as 9.2 years.

• Journal of the Semiconductor & Display Technology
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• v.19 no.1
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• pp.42-48
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• 2020

As global warming accelerates, eco-friendly electric cars are being developed to reduce carbon dioxide emissions, and power conversion inverters are used to drive motors. Among inverter components, DC-link capacitor is heated by high current usage, which causes problems such as performance and life-saving of inverter. Although metal cases with good thermal performance have been used to solve this problem, it is difficult to apply them in practice due to insulation problems with other parts. In this paper, the Heat-Generation influence factor of DC-link capacitor is analyzed. Variables on heat-generation are set at 3 levels for film width, inductance, and film thickness. Box-Behnken to 13 tests using the design and minimal deviations, e.g. through the experiment three times by each level. The surface of the film k type by attaching the sensor current is measured temperature. Capacitance was set to a minimum level of 200 ㎌ and had a frequency of 16 kHz with Worst case, ambient temperature of 85℃ and a ripple current of 50 Ams was applied. The temperature at the measurement point was collected in the data logger after sampling at 1 minute intervals for 2 hours after saturation with the ambient temperature. This experiment confirmed that setup factors are correlated with heat-generation.

• Korean Journal of Human Ecology
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• v.20 no.6
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• pp.1135-1151
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• 2011

This study examined green consumption behavior according to the lifestyles of college students. The data were collected from 314 college students in Yeungnam region by a self-administered questionnaire. Frequencies, Cronbach's alpha, factor analysis, cluster analysis, chi-square tests, one-way analysis of variance, Duncan's multiple range tests, Pearson's correlation analysis, and multiple regression analyses were conducted by SPSS Windows V.18.0. According to the result of factor analysis, lifestyles were categorized into six factors: thrift-saving type, enthusiastic activity type, brand ostentation type, freedom-seeking type, material oriented type, and practice-seeking type. Cluster analysis showed respondents belonged to one of four groups: thrift practice group, indifference group, freedom-seeking group, and material ostentation group. The levels of green purchase behavior, green usage behavior and green disposal behavior of the respondents was not high. The thrift practice group showed higher levels of green purchase behavior, green usage behavior, and green disposal behavior. Finally, according to multiple regression analyses, environmental consciousness, knowledge about green consumption, lifestyle groups were the significant factors affecting green consumption behaviors. These results imply that green consumption education for college students should be activated to induce green life.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.4
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• pp.42-48
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• 2014

Sewage treatment facilities can purify sewage enough to be send to river or sea water, that discharged from human life and industrial activities. In the sewage treatment process, we can get large amount of by-product energy resources and materials such as heat of sewage, digester gas and purified water etc., it can be utilized by applying various technologies thereby we can reduce energy consumption in the process. In this paper, it was analyzed using the data collected from the operational case study for the energy savings effect that can be obtained when using the digester gas, one of the by-product materials of sewage treatment process, for electric power generation. Cost of 623million won is an annual reduction of 4,032MWh corresponding 9% of the annual electricity consumption of the sewage treatment plant, such an alternative power generation using digester gas was proposed in this paper has been verified the feasibility of the proposed reduction of energy.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.4
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• pp.35-42
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• 2014

This study aimed to explore the methods to provide life service for hinterland villages, which is the biggest function of the seat of myeon in rural areas, and enhance central functions/roles. This study also aimed to provide basic information to establish a direction of the future projects of the seat of myeon through empirical study on the comprehensive improvement projects of the seats of eup and myeon and related demanders' perception for sustainable rural area. Based on the results, a variety of hardware manuals are correspondent with present rural situations in the comprehensive improvement projects of the seats of eup and myeon. Therefore, community-based welfare facilities should be expanded. Also, village infrastructure facilities and village landscape projects should be promoted to improve pedestrian environment. Finally, switching into an ecological environment project should be considered to improve village environment as well as supply energy saving facilities.

• KIEAE Journal
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• v.12 no.6
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• pp.39-47
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• 2012

Recently, the green building and energy connection system are establishing. But, National certification system for environment-Friendly Buildings is indicated hangup about energy efficiency of building. Commissioning, energy conservation, renewable energy, carbon dioxide emissions, it is determined that the energy associated with LEED and GBCC four items of the comparative analysis showed the following results. First, on the practical performance of the system after the completion of commissioning of the energy associated with the system completed until after the final performance for secure operation from the planning stage to verify and document systematically how to perform, but the domestic review and verification is incomplete. Second, the use of energy-saving and renewable energy is directly related to the energy consumption of the building, but GBCC the strengthening of standards on how to evaluate it is deemed necessary. Finally, the evaluation of the reduction of carbon dioxide emissions, LEED Unlike GBCC the life-cycle of the system without considering the global warming index only because a substantial step in the operating efficiency can not be assessed. Based on this study GBCC energy savings through efficiency to actively carry out research through a systematic analysis of the basic guidelines to proceed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.5
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• pp.483-490
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• 2009

The objective of this development project is to localize an automatic molten metal supplier that has been distributed by WESTOMAT, Germany, throughout the world. To achieve this purpose, an energy-saving pressurized dosing furnace and molten metal differential pressure control system that Is able to automatically supply a determined quantity of aluminum molten metal were developed. The localized equipment was installed in a site. Also, the results of the test operation of this equipment can be summarized as follows: It was able to improve the productivity because there were small decreases in supplying speeds and small losses in wastes compared to the existing mechanical molten metal supplier. Also, it was able to minimize the cost in maintenances due to the direct application of high temperature molten metals to molds. In addition, there were small energy losses due to the use of high thermal insulators compared to the existing reverberating furnace and able to prolong the life-time of furnaces and produce good quality nonferrous metals because it represented small carbon refractories and alumina in applied molten metals. Furthermore, it demonstrated no particular differences by objectively comparing it with the product by WESTOMAT.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.1
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• pp.15-24
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• 2009

The energy usage and the economical feasibility of the typical two story office building in the three urban locations of South Korea are evaluated as the eight orientations. The smallest energy consume is shown at the true south. The ranges of the low energy consume are $-3l5^{\circ}{\sim}0^{\circ}\;and\;-135^{\circ}{\sim}-180^{\circ}$. There are obvious advantages of passive solar designs such as using a fully glazed facade at the true south in the building. The General Low voltage plan is the effective way for the office building when does not required the high voltage electricity. The energy cost of KEPCO is compared to that of XCEL ENERGY. The portion of the customer charge of XCEL ENERGY is about 10% but it is about 50% of the total tariff of KEPCO. The effective way to save the energy cost is by reducing the operating energy of XCEL ENERGY plane but the most effective way is reduce the contracting energy of KEPCO plane.

• Aerospace Engineering and Technology
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• v.1 no.1
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• pp.97-105
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• 2002

The mission life of a satellite determines the amount of fuel required on-board, while the total mass requirement limits the fuel to be loaded. Hence, for the design of thruster control loop, not only the satellite pointing accuracy but the saving of fuel is to be considered. In this paper, a two-step fuzzy controller is proposed for the thruster control loop to save fuel consumption. This approach combines requirements for pointing control accuracy with minimum fuel consumption into a fuzzy controller design. To demonstrate this approach, we have designed a fuzzy controller for the Sun Pointing Mode of KOMPSAT-1. The performance of this fuzzy controller design is compared with that of PD controller used for KOMPSAT-1.