• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.1101-1116
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• 1996

It is desirable to use the renewable energy for the greenhouse heating in winter season, it makes possible not only to save fossil fuel and conserve green farm environment but also to promote the quality of agricultural products and reduce the agricultural production cost. In this study the heat pump system was developed to use the natural energy as thermal energy resource for the thermal environment control of the greenhouse.

• Journal of Environmental Science International
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• v.9 no.3
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• pp.185-191
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• 2000

Sustainable development has been the key concept, both in economic policies and in environmental management since 1970s. In the view of systems ecology, sustainable resource use strategies are considered to be essential in achieving sustainable development. During the last three decades, the discipline of systems ecology has applied ecological energetic analysis to the evaluation of the contribution of natural environments to economic systems. ENERGY analysis of main energy flows driving the economy of humans and life support systems of a city was made including environmental energies, fuel, and inputs, all expressed as solar emjoules. Total EMERGY use of Pusan was 3.89 E22 sej/yr, about 90 percent of it was purchased sources from outside during eleven years from 1985 to 1995. EMERGY flows from the environment were less than 10 percent. EMERGY yield ratio and environmental loading ratio were 1.10 and 10.45, respectively. EMERGY sustainability index is there(ore less than one, which is indicative of highly developed consumer oriented economies. Development of a city has been achieved in the short run by the economic growth, but it can be sustained in the long run by the use of renewable resource systems.

• Journal of Family Resource Management and Policy Review
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• v.19 no.4
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• pp.55-70
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• 2015

This study aims to clarify the difference between scores for time management practice and the self-evaluation of time use according to time rules in families. This study used data obtained from the first survey on after-school activities in 2008, conducted by the Benesse Educational Research and Development Institute in Japan. The study sample consists of 3,372 middle school students. First, scores for independence and planning were highest in third grade, yet the score for regularity was also lowest in third grade. There will be different lifestyles even among middle school students of the same grade, so it is necessary to consider their characteristics and family rules. Second, the scores for independence, regularity and planning were lowest in groups whose families had rules about time (time rules for curfew, time rules for watching television, time rules for playing games), but in which those rules were not kept. These results were similar for both boys and girls and show that it is more important keep rules rather than to make rules.

• Resources Recycling
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• v.29 no.6
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• pp.15-26
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• 2020

In recent years, there is an increasing interest in environmental friendly treatment of waste-plastics in terms of the generation of microplastics. Accordingly, the recycling of waste-plastics is very important because it provides advantages of volume reduction, mitigation of carbon dioxide emission, and reproduction of value-added products. In particular, in order to recycle the eco-friendly waste-plastics, it is necessary to use a physical separation methods, and among them, flotation separation, which can separate material (i.e., polymer component) in waste-plastics is well known as a very effective separation method in terms of material recycle. Therefore, in this review, the research trend of flotation separation for effective separation of mixture waste-plastics was investigated. In addition, through the reported research results, approaches to use as new functional materials from polymers, which are raw materials for waste-plastics, are summarized.

• Journal of Environmental Science International
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• v.24 no.8
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• pp.1003-1013
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• 2015

The Ministry of Trade, Industry and Energy is now placing emphasis on the importance of a new and renewable energy resource map service as an essential means of promoting the dissemination and adoption of renewable energy and other related industrial activities. To raise satisfaction with the new and renewable energy resource map service and promote its utilization, a survey was conducted on a sample group with an academic research background, i.e. employees of the Korea Institute of Energy Research (KIER) who have a thorough understanding of the technological concepts behind the new and renewable energy resource map. Statistical analysis of the survey results showed a high level of overall satisfaction with the web service for the new and renewable energy resource map. Therefore, it was concluded that the development of practical contents rather than the enhancement of web service convenience is required. A statistically significant trend was also observed whereby, the longer the professional career of the survey respondents, the greater their perception and utilization of, and satisfaction with, the enhanced service, which indicates that their level of understanding and utilization of technological concepts corresponds to their research experience record. In addition, the results obtained from the questionnaires regarding the evaluation of the utilization value of the resource map service indicated that use of the service was equally high in terms of political, business and academic applications. The results confirmed the need to develop multidimensional resource map contents that can be applied to as many fields as possible, rather than focusing on a specific terrain.

• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.692-700
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• 2018

In this study, the results of PBDEs and HBCDs of the products and waste that contain BFRs such as domestic electronic products, automobiles and textile products were compared with international management standards, and their excess rates were calculated. Deca-BDE was detected among the PBDEs in TV rear cover plastics, car seats, automotive interior plastics, and automobile shredding residues of products and waste containing BFRs. The comparison with Basel Convention management standards (1,000 mg/kg) for PBDE-containing wastes (4 types in total) shows that the excess rate of all samples was less than 1.5%. The estimated excess rate compared to the EU and Basel convention management standards (1,000 mg/kg) for PBDEs (4 species + deca-BDE) and TV rear cover plastics was 37.5% (30 of 80 samples exceeded the standards). The estimated excess rate compared to the Basel convention management standards (1,000 mg/kg) for HBCD, building materials products and waste was 15.7% (17 of 108 samples exceeded the standards). In the case of PBDEs, it is necessary to remove only the rear cover of CRT TV among the electric and electronic products and treat it in the flame retardant treatment facility to improve the recycling collection system. In the case of HBCD, it is necessary to appropriately dispose of the recycled materials, heat insulation materials, TV plastics, and styrofoam in marine fishery among construction materials and restrict the use as recycled raw materials.

• Journal of Korean Society of Rural Planning
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• v.11 no.3 s.28
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• pp.19-27
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• 2005

Rural Korea has been becoming heavily aged societies from the end of 20th century due to the massive depopulation of young generation and extension of the average span of human beings. Although rural communities in Korea had been traditionally based on closely webbed social relations, almost all of community self-help organizations disappeared in recent time with very strong urbanization trend. However, almost all rural villages in Korea have the village seniors' union -'NO-IN-HOE' in Korean speaking- of which members usually use, operate and maintain community facilities in terms of voluntary base. Using these facilities, most of public/common/private services and community activities have been being served or provided. So, the purpose of this study is to investigate the usage tendency of community facilities and needs of the rural elderly and to propose the improvement strategies for their optimum usage. For this purpose, data was gathered both from community (107 villages) and individual level surveys(881 older people). The statistical method used for data analysis was descriptive statistics. The major findings were as follows : It was found that the dominant family type of the rural elderly was elderly-only household (75%) with very limited economic capability. There are 2$\sim$3 common community facilities with village including the seniors' center -'KYOUNG-RO-DANG' in Korean speaking. Many of the elderly (74%) use the center once or twice per week. There are several rooms in the center, like as kitchen bathroom and health room, of which usage frequency differs respectively. Many rural elderly want assistance from out-of-village for good maintenance and free use of these facilities.

• International Journal of Contents
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• v.14 no.2
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• pp.1-6
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• 2018

In a wireless mobile communication system, a pilot signal has been considered to be a necessary signal for estimating a changing channel between a base station and a terminal. All mobile communication systems developed so far have a specification for transmitting pilot signals. However, although the pilot signal transmission is easy to estimate the channel,(Ed: unclear wording: it is easy to use the pilot signal transmission to estimate the channel?) it should be minimized because it uses radio resources for data transmission. In this paper, we propose a pilotless channel estimation scheme (PCE) by introducing the clustering method of unsupervised learning used in our deep learning into channel estimation.(Ed: highlight- unclear) The PCE estimates the channel using only the data symbols without using the pilot signal at all. Also, to apply PCE to a real system, we evaluated the performance of PCE based on the resource block (RB), which is a resource allocation unit used in LTE. According to the results of this study, the PCE always provides a better mean square error (MSE) performance than the least square estimator using pilots, although it does not use the pilot signal at all. The MSE performance of the PCE is affected by the number of data symbols used and the frequency selectivity of the channel. In this paper, we provide simulation results considering various effects(Ed: unclear, clarify).

• KIPS Transactions on Computer and Communication Systems
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• v.3 no.7
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• pp.219-230
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• 2014

In the cloud computing environment, cloud service users purchase and use the virtualized resources from cloud resource providers on a pay as you go manner. Typically, there are two billing plans for computing resource allocation adopted by large cloud resource providers such as Amazon, Gogrid, and Microsoft, on-demand and reserved plans. Reserved Virtual Machine(VM) instance is provided to users based on the lengthy allocation with the cheaper price than the one of on-demand VM instance which is based on shortly allocation. With the proper mixture allocation of reserved and on-demand VM corresponding to users' requests, cloud service providers are able to reduce the resource allocation cost. To do this, prior researches about VM allocation scheme have been focused on the optimization approach with the users' request prediction techniques. However, it is difficult to predict the expected demands exactly because there are various cloud service users and the their request patterns are heavily fluctuated in reality. Moreover, the previous optimization processing techniques might require unacceptable huge time so it is hard to apply them to the current cloud computing system. In this paper, we propose the cloud brokering system with the adaptive VM allocation schemes called A3R(Adaptive 3 Resource allocation schemes) that do not need any optimization processes and kinds of prediction techniques. By using A3R, the VM instances are allocated to users in response to their service demands adaptively. We demonstrate that our proposed schemes are able to reduce the resource use cost significantly while maintaining the acceptable Quality of Service(QoS) of cloud service users through the evaluation results.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.10
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• pp.1101-1108
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• 2015

In this paper, to provide a method and system for providing a network separation virtual machine environment. How to provide this virtual machine environment include phase generating necessary virtual resource requirement for the perform of virtual function and transfer to network changing protocol about request of registration virtual resource. For this reason, Registration procedure is to use a virtual machine for a virtual computing resource allocation and separation combined network any time, it became possible between servers and clients, or mobile phone. At any time, it is possible to process the work in the same environment as in a computer to access the Internet.