• Journal of the Korean Ceramic Society
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• v.39 no.10
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• pp.1007-1010
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• 2002

Alpha alumina platelet particles were synthesized from the powder mixture of ${\gamma}-Al_2O_3and\;Na_2SO_4$ with the use of microwave heating. The characteristics of the particles such as particle size and particle size distribution were compared with those of particles obtained from the same mixture without the use of microwave. Sample with the use of microwave showed small particle size and narrow particle size distribution compared to that without the use of microwave.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.61-73
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• 2023

As smartphone use is increasing within the middle-aged population, society should pay closer attention to the mental health problems associated with smartphone addiction. This study examines the possibility that depression, anxiety, and ADHD can be interpreted not only as negative aspects, but also as positive aspects, in an addiction-related individual. We used habitual and addictive smartphone behavior as the dependent variables; anxiety, ADHD, depression, and habitual smartphone use as the independent variables; and self-control as a moderating variable. Depression and ADHD in smartphone users were found to be associated with higher levels of addictive smartphone use. Anxiety was having negative effect on addictive smartphone use. However, habitual smartphone use didn't significantly affect addictive smartphone use. Further analysis indicated that depression, anxiety, and ADHD have mediating effects on habitual smartphone use. This study confirmed that psychological factors in adults, as well as habitual/addictive smartphone use and self-control, significantly influence smartphone overdependence.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.27-39
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• 2006

The purpose of this study was to present a guideline for the construction of children park that can create a quality of dwelling and be easily approached and utilized by residents. In order to present a direction of planning, the investigator examined the actual state of children park in low-rise house residential area, and analyzed its general characteristics. And the discriminative characteristics according to the standpoints of planning of children park. The analytic standpoints were classified into the size and disposition of park, the nature of adjacent street and the utilization of park, and the satisfaction and requirement for the internal space of park. The guideline of planning of children park are as follow: (1) The disposition and size of children park: the children park must be disposed convenient use of all the residents. (2) The environment around including approaching streets and facilities around: residents' recognition and access in their everyday life must be considered in relation to the neighborhood streets and surrounding facilities. (3) The composition and utilization of internal space: the internal space must support all the activities of users, and reflect users' requirements in order to induce them to use it continuously.

• Journal of Environmental Science International
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• v.30 no.6
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• pp.441-454
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• 2021

This study intended to propose an improvement plan to improve user satisfaction by establishing a park and green space masterplan by comparing its current status and surveying the residents' perception of green park services in two regions. The study results showed that the residents are aware of the physical and qualitative aspects of the green park environment. In addition, the quality level of the green park that people may actually use in everyday life was considered a factor for evaluation of satisfaction. In addition, it was found that the residents, who are actual users of the green park services, evaluated the satisfaction of use considering the qualitative characteristics of the green park, such as 'quality of green park' and 'availability of green park.' As a result, efforts are required to create and improve the quality of green parks efficiently based on establishing qualitative indicators, a survey of residents' perception, and quantitative analysis to develop policy directions and guidelines of the park and green space masterplan.

• Korean Journal of Environment and Ecology
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• v.9 no.2
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• pp.211-220
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• 1996

5 major trails of Odaesan National Park were selected to investigate the use impacts on environmental deterioration of trail accreding to the different amunt of use. The entire width, bare width, maximum depth and slope of trail as the trail comdition surveyed at the total of 120 points were significantly greater on the more heavily-used trail. Major deterioration types of trail were root-exposure, rock-exposure, deepening and divergence in order of frquency and trail conditions of deteriorated points were significantly different from those of non-deteriorated points. The damaged area more severe than Class 4 on trail reached about 379m$^{2}$/km in total, and especcially about 1,196m$^{2}$/km in the section between Chodmyolbogung and Pirobong of Sangwonsa trail. The dominant trees of trail edge vegetation could be Quercus mongolica in upper layer, but in lower layer Rhododecdron schilipenbachii for slope and Actinidia arguta for ridge. Coverage and number of individuals of lower vegetation in trail edge were the lowest on the Sangwonsa trail of the largest use amount, and each trail was dissimilar in species composition of lower layer of edge vegetation.

• Journal of Korean Society on Water Environment
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• v.24 no.6
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• pp.806-816
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• 2008

In recent years, increases in impervious areas with rapid urbanization and land use changes are causing numerous hydrologic and environmental problems. In this study Low Impact Development (LID) was applied to investigate changes in runoff and peak runoff with LID plans. SWMM 5.0 was used to simulate LID Integrated Management Practices (IMPs) at study area. The SWMM estimated total runoff volume with conventional land use planning is (82.3%, 46.44 mm), (99%, 73.16 mm) greater than total runoff before urbanization, while total runoff with LID is (11.1%, 46.44 mm), (49%, 73.16 mm) greater than those before urbanization. With the LID adoption in land use planning, pervious area increases by 49.8% compared with that from the conventional urban land use planning, resulting in (32.7%, 46.44 mm), (23.6%, 73.16 mm) decrease in total runoff, and (32.6%, 46.44 mm), (18.5%, 73.16 mm) decreases in peak rate runoff. The results obtained from this study indicate that peak rate runoff, time to peak, and total runoff can be reduced with the LID in urban land use planning because the LID secures pervious areas with various LID IMPs. The SWMM simulated result using design storm data and the US EPA suggested CN values for various LID IMPs implies that how environment-friendly urban land use planning with the LID adoption is important for sustainable development at urbanizing watershed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.3
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• pp.1-17
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• 2023

Korea's natural parks are managed by dividing them into four use districts: nature preservation district, natural environment district, cultural heritage district, and park village district within the park under the goal of 'conservation and sustainable use of natural parks'. However, the use districts divided in this way are designated by reflecting the results derived from the simple drawing overlapping method, and there is a limit in that objective and scientific evidence for this is insufficient. In addition, in Taeanhaean National Park, the case of this study, only a very small area of less than 1% of the nature preservation district is designated, and the natural environment district that serves as a buffer space is designated on an excessively wide scale, making it difficult to efficiently manage the national park. Therefore, the use district is not fulfilling its role. In this study, the purpose of this study was to present a method for analyzing the spatial characteristics of natural parks using environmental indicators and unsupervised learning analysis methods to set the use districts of natural parks. In this study, evaluation indicators that can evaluate the natural and human environments were derived, and the distribution patterns for each indicator were analyzed. Afterwards, by applying Self-Organizing Map (SOM) analysis, one of the unsupervised learning analysis methods, districts with similar characteristics were derived in Taeanhaean National Park, and the characteristics of each district were analyzed. As a result of the study, 7 districts with different characteristics were derived in Taeanhaean National Park, and by examining the contribution of each indicator together, it was possible to reveal that each district had different representative characteristics even though it was an adjacent area. This study evaluated natural parks by comprehensively considering the indicators of the natural and human environments. In addition, the SOM method used in the study is meaningful in that it can provide scientific and objective grounds for the existing zoning and apply it to the management plan.

• Management Science and Financial Engineering
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• v.21 no.2
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• pp.9-11
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• 2015

This note is concerned with the use of incomplete weights in multiple criteria decision making. In an earlier study, an optimistic use of incomplete weights is developed to prioritize decision alternatives, which applies the most favorable set of weights to the alternative to be evaluated. In this note, we develop a method for a pessimistic use, thereby applying the least favorable weight set to the evaluated alternative. This development makes possible a more detailed prioritization of competing alternatives, and hence enhances decision-making powers.

• Proceedings of the KIEE Conference
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• summer
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• pp.680-682
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• 2004

수요관리 프로그램의 개발과 시행을 위해 서는 End-Use별로 수요예측과 잠재량 평가가 필수적이다. 업무용 전력수요는 건물용도에 따라 수요패턴이 상이하다. 여기서는 건물용도별 기준수요 예측을 위한 알고리즘과 절차를 제시하였으며, 이를 토대로 시산분석을 하였다. 용도별 전력수요는 사무실, 호텔, 병원, 도소매, 학교, 창고, 식당, 식료품, 체육시설 둥 건물용도로 구분하였으며, End-Use는 이중 6개 용도에 대해 조명, 동력, 공조, 사무, 기타 등 5개로 나누어 추정하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.667-672
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• 2007

Land-use in Cheongju region is changing rapidly because of the increased interactions of human activities with the environment as population increases. We used multi-temporal Landsat images (1991 and 2000) and DEM data in a post-classification analysis with GIS to map land-use distribution and to analyse factors influencing the land-use changes for Cheongju City. Land-use statistics revealed that substantial land-use changes have taken place and that the built-up areas have expanded by about $17.57km^2(11.47%)$ over the study period (1991-2000). Agricultural lands and forests have decreased substantially while urban and barren lands have been on the increase. Rapid economic developments together with the increasing population were noted to be the major factors influencing rapid land use changes. Urban expansion has replaced urban and barren lands, thereby affecting habitat quality and leading to serious environmental degradation.