• 한국전기전자재료학회논문지
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• 제21권8호
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• pp.738-748
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• 2008

In this study, it has been investigated on the changing behavior of electrical properties in $ZnO-Bi_2O_3-Sb_2O_3$ (Sb/Bi=2.0, 1.0 and 0.5) ceramics. The samples were prepared by conventional ceramic process, and then characterized by I-V, C-V curve plots, impedance and modulus spectroscopy (IS & MS) measurement. The electrical properties of ZBS systems were strongly dependent on Sb/Bi. In ZBS systems, the varistor characteristics were deteriorated noticeably with increasing Sb/Bi and the donor density and interface state density were increased with increasing Sb/Bi. On the other hand, we observed that the grain boundary reacted actively with the ambient oxygen according to Sb/Bi ratio. Especially the grain boundaries of Sb/Bi=0.5 systems were divided into two types, i.e. sensitive to oxygen and thus electrically active one and electrically inactive intergranular one with temperature. Besides, the increased pyrochlore and $\beta$-spinel phase with Sb/Bi ratio caused the distributional inhomogeneity in the grain boundary barrier height and the temperature instability. To the contrary, the grain boundary layer was relatively homogeneous and more stable to temperature change and kept the system highly nonlinear at high Bi-rich phase contents.

• Journal of Preventive Medicine and Public Health
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• 제42권6호
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• pp.392-402
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• 2009

Objectives : The aims of this paper were to develop the composite deprivation index (CDI) for the sub-district (Eup-Myen-Dong) levels based on the theory of social exclusion and to explore the relationship between the CDI and the standardized mortality ratio (SMR). Methods : The paper calculated the age adjusted SMR and we included five dimensions of social exclusion for CDI; unemployment, poverty, housing, labor and social network. The proxy variables of the five dimensions were the proportion of unemployed males, the percent of recipients receiving National Basic Livelihood Security Act benefits, the proportion of households under the minimum housing standard, the proportion of people with a low social class and the proportion of single-parent household. All the variables were standardized using geometric transformation and then we summed up them for a single index. The paper utilized the 2004-2006 National Death Registry data, the 2003-2006 national residents' registration data, the 2005 Population Census data and the 2005-2006 means-tested benefit recipients' data. Results : The figures were 115.6, 105.8 and 105.1 for the CDI of metropolitan areas (big cities), middle size cities and rural areas, respectively. The distributional variation of the CDI was the highest in metropolitan areas (8.9 - 353.7) and the lowest was in the rural areas (26.8 - 209.7). The extent and relative differences of deprivation increased with urbanization. Compared to the Townsend and Carstairs index, the CDI better represented the characteristics of rural deprivation. The correlation with the SMR was statistically significant and the direction of the CDI effects on the SMR was in accordance with that of the previous studies. Conclusions : The study findings indicated mortality inequalities due to the difference in the CDI. Despite the attempt to improve deprivation measures, further research is warranted for the consensus development of a deprivation index.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제4권4호
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• pp.159-176
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• 2023

The conservation of the raccoon dog (Nyctereutes procyonoides) in South Korea requires the protection and preservation of natural habitats while additionally ensuring coexistence with human activities. Applying habitat map modeling techniques provides information regarding the distributional patterns of raccoon dogs and assists in the development of future conservation strategies. The purpose of this study is to generate potential habitat distribution maps for the raccoon dog in South Korea using geospatial technology-based models. These models include the frequency ratio (FR) as a bivariate statistical approach, the group method of data handling (GMDH) as a machine learning algorithm, and convolutional neural network (CNN) and long short-term memory (LSTM) as deep learning algorithms. Moreover, the imperialist competitive algorithm (ICA) is used to fine-tune the hyperparameters of the machine learning and deep learning models. Moreover, there are 14 habitat characteristics used for developing the models: elevation, slope, valley depth, topographic wetness index, terrain roughness index, slope height, surface area, slope length and steepness factor (LS factor), normalized difference vegetation index, normalized difference water index, distance to drainage, distance to roads, drainage density, and morphometric features. The accuracy of prediction is evaluated using the area under the receiver operating characteristic curve. The results indicate comparable performances of all models. However, the CNN demonstrates superior capacity for prediction, achieving accuracies of 76.3% and 75.7% for the training and validation processes, respectively. The maps of potential habitat distribution are generated for five different levels of potentiality: very low, low, moderate, high, and very high.

• 한국지리정보학회지
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• 제18권4호
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• pp.100-118
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• 2015

본 연구는 위성영상을 이용하여 객체기반 토지피복 분류도를 구축하고 공간통계기법을 통하여 토지피복의 분류항목별 분포패턴을 파악하였다. 객체기반 분류는 분광정보, 질감정보, 분광정보와 질감정보의 조합에 의하여 각각의 토지피복 분류도를 구축하였으며, 정확도 평가를 통하여 최적의 토지피복 분류도를 선정하였다. 또한, 토지피복의 분류항목별 공간적 분포패턴을 파악하기 위하여 핫스팟 분석을 실시하여 정량화하였다. 객체기반 분류를 위한 최적의 가중치는 Scale 52, Shape 0.4, Color 0.6, Compactness 0.5, Smoothness 0.5로 선정하였다. 토지피복 분류도는 분광정보와 질감정보의 조합을 사용하였을 때, 전체 분류정확도가 가장 높았으며, 특히 밭과 시설재배지, 나지의 경우 분광정보만을 사용하였을 때 보다 정확도가 약 12% 이상 증가하였다. DMZ일원의 분류항목별 면적비율은 산림 > 논 > 교통시설 > 초지 > 밭 > 나지 > 건물 > 수역 > 시설재배지 순으로 높았으며, 특히, 양구군의 밭과 교통시설은 민간인통제선 이북지역, 철원군의 밭, 인제군의 산림과 교통시설은 민간인통제선 이남지역에서 주로 분포하는 것으로 나타났다. 분류항목별 분포 패턴의 경우, 농업과 관련된 논, 밭, 시설재배지의 핫스팟(hot spot)은 철원군의 평야 지역과 양구군의 분지 지역에 집중 분포하였다. 나지, 수역, 건물, 도로의 핫스팟 지역은 농업과 관련된 핫스팟 지역과 분포 패턴이 유사한 반면, 산림과 초지의 핫스팟 지역과는 분포 패턴이 상이하였다.

• Journal of Preventive Medicine and Public Health
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• 제20권2호
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• pp.301-311
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• 1987

의사들의 지역간 분포양상 및 불균형 정도를 체계적으로 측정하여, 장기적이고 합리적인 의사인력의 배분정책 수립을 위한 기초자료로 제시하고자 1980년과 1985년의 인구센서스 통계자료와 정기의사 신고자료를 이용하여 의사, 일반의, 전문의의 지역간 불균형정도를 분석한 결과는 다음과 같다. 1980년에는 전체의사의 10.4%가 군지역에 위치하고 있었으나 1985년에는 9.6%로 군지역 분포율이 낮아졌고, 인구 100,000명당 의사수는 1980년에는 군지역에 9.18명이던 것이 1985년에는 12.95명으로 증가했다. 일반의는 1980년에 군지역에 14.7% 분포되어 있었으나 1985년에는 12.7%로 낮아졌고, 인구 100,000명당 의사수는 7.13에서 7.29명으로 증가했다. 전문의의 경우 1980년에는 5.1%가 군지역에 위치하고 있었으나 1985년에는 7.3% 증가되었고, 인구 100,000명당 의사수도 2.05명에서 5.66명으로 증가했다. 군지역에의 분포비율이 10%를 초과한 전문과목별 전문의는 일반외과와 예방의학과 뿐이었으며, 1980년에 비해 1985년에 군지역 분포비율이 흉부외과 전문의를 제외하고는 모든 전문과목에서 높아졌다. Gini계수의 1980년$\sim$1985년간 변화율은 의사 -15.40%, 일반의 18.01%, 전문의 -10.43%로서 일반의의 불균형 정도가 심화되었고, 구지역간과 군지역간에는 모든 의사의 분포가, 시지역간에는 일반의의 분포만 더 불균형하게 된 것으로 나타났다. 전문의 중에서는 소아과 전문의의 변화율이 -12.24%로 가장 높았으며, 신경외과, 흉부외과, 성형외과, 안과, 결핵과, 예방의학과, 해부병리과 전문의는 1980년보다 1985년에 Gini계수가 더 높아졌다. 그리고 1985년 기준으로 일반외과 전문의의 Gini계수만 0.4369로 0.5이하였고, 0.8이상인 전문과목은 성형외과, 결핵과, 임상병리과, 해부병리과, 재활의학과 등이었다. 의사의 지역간 균형분포를 위해서는 의사의 지역간 분포요인 분석 연구를 통해, 이를 기초로 적절한 배분정책을 수립해야 할 것이며, 공공의료인력의 효과적인 활용이 필요할 것으로 보인다.

• 한국해안·해양공학회논문집
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• 제27권4호
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• pp.274-279
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• 2015

동해 중부에 위치한 속초항 연안에서 약 11년간 취득한 파랑자료를 스펙트럼법과 파별분석법을 사용하여 분석하고 대표적인 파랑 특성을 검토하였다. 유의파고는 동계에 크고 하계에 작으며, 첨두주기도 동계에 길고 하계에 짧은 특성을 나타내었다. 관측된 최대 유의파고는 8.95 m 였으며 동해선풍에 의하여 발생되었다. 유의파고와 첨두주기 모두 그 분포 형태를 Generalized Gamma 및 Generalized Extreme Value 분포함수보다는 Kernel 분포함수가 보다 잘 재현하였다. 한편, 인근 해역에서의 설계 및 시공에 도움을 줄 수 있도록 파고 자료를 월별 및 파고 구간별로 세분하고 누적출현율을 제시하였다.

• 한국환경복원기술학회지
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• 제23권2호
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• pp.33-47
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• 2020

With population losses and stagnant or depressed economies, the local governments embrace shrinkage and accept having a significantly smaller population. Both the initial and ongoing causes of shrinkage hold dramatic effects on the city and its remaining residents. In this context, vacant land increases as an overabundance of unused infrastructure is demolished and municipalities become burdened with increasing maintenance costs of this land. The result is that vacant land often experiences minimal management relative to social norms and have chance to provide a setting for ecological processes with urban rightsizing strategy. Therefore, urban ecosystems undergo major shifts in structure and function. We need to better understand the possibilities of where and how much of houses and land will be abandoned to assist land planners and policymakers to mitigate conflict between optimal ecological and sociological outcomes. This article, therefore, aims to identify distributional characteristics of vacant houses and lands with case study of Mokpo. The study found and verified affecting factors of vacant houses and lands by type through the use of a Maxent model and spatial data that explained housing choice and preference theory. We can predict the vacancies with the spatial variables such as land price, the population ratio over 65, and the distance from security facility. Based on the analysis, the ways of managing housing and land vacancy for sustainable development and ecological restoration method are discussed.

• 한국주거학회논문집
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• 제24권5호
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• pp.57-67
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• 2013

The purpose of this study is to find out distributional principles of the shop-houses in residential district through physical composition of residential area. Through the research that are based on literature and field survey, it analysed the relation between physical composition of residential area and the shop-houses of selected four sites under similar urban condition where land readjustment project were held. The consequences of this study are summarized as follows; 1) A road that is not penetrating the inside a residential area is seemed to have low occupancy of shops comparing to other roads with similar hierarchy. And the shops functions as convenience facilities. It can be inferred from the statement above that even a road with higher hierarchy is not easy to form commercial area if without penetrating the residential area. 2) According to the size and the arranged method of Inner blocks of residential area towards major roads, distribution of shop-houses appear to be different. In other words, when shop-houses are located along the roads, the proportion of shop was higher than when located perpendicular to the roads. 3) When the number of average lots are little and the size of block is small, usually, street ratio and the number of corners gets higher, which eventually increases the number of shop-houses.

• 한국수산과학회지
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• 제9권2호
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• pp.111-119
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• 1976

Discoloration of canned boiled oyster namely greening, yellowing and browning often occur separately or associatively in the storage of the product. Greening is mainly caused by the appearance of chlorophyll and its derivatives on the surface around the digestive diverticula of the oyster and yellowing by dispersion of carotenoid. Browning reactions by sugar amino condensation or enzymatic action, tyrosinase, also cause an undesirable color development. In this paper, the stability and the changes in distributional or partitional ratio of chlorophyll and carotenoid pigment of meat vs viscera in raw and canned oyster during six month storage in order to measure the dispersion rate of both pigments between meat and viscera, and to evaluate the feasibility of discoloration of oyster meat. The development of brownish pigment and the toss of free tyrosine in oyster were also determined to compare the readiness of color development. In addition the influence of processing and storage conditions to the dispersion rate and the tendency of discoloration, and finally the effect of inhibitor were discussed. The results showed that greening or yellowing was initiated by the dispersion of chlorophyll or carotenoids from viscera to the meat of oyster, and the dispersion rate of carotenoid was much higher than the chlorophyll's, so that, yellowing appeared a leading reaction of discoloration. The dispersion rate was obviously fastened by raising the temperature in the process of sterilization and storage. Consequently, the low temperature storage could largely retard the occurance of yellowing or greening of oyster meat. The pH control of canned oyster did not seem to affect the dispersion of pigment but significantly did on the stability of the piqments. Browning by the reaction of sugar-amino condensation and enzymatic oxidation of tyrosine was positively detected in canned oyster meat. The development of brownish color was influenced rather by the storage temperature than the heating process. Addition of sodium sulfite in can or treating the boiled oyster with sulfite solution prior to filling seemed possibly inhibit the color development particularly in cold-storaged oyster meat.

• 환경영향평가
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• 제20권5호
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• pp.685-695
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• 2011

Through the analyses of the distribution characteristics and management practices of the wildlife protection areas, this study intends to present basic data for improving the management of protected areas. 1) Based on the aggregate results of the protected areas, the average ratio of the metro-city and provincial areas to the designated protected areas was 1.49%; except for Chungcheongbuk-do (8.83%) and Gyeongsangnam-do (3.43%), most regions showed specified percentages of about 1%, whereby the analysis suggested that the designated protected areas were too small. 2) Considering the fact that most (86.16%) of the wildlife protection areas are in the regions that are of ecological nature level of grade 1, green nature level of grade 8 or better, and of legal conservation regions and districts, it was shown that these reserves are distributed in regions with excellent natural environmental conditions. 3) Designation of protected areas for the protection of wildlife and fish is deemed to be necessary. Although there are 588 wildlife & plant reserves, there are absolutely no designated areas for protecting plant and fish species. 4) Based on the results of an analysis of the current distribution by types, 92.47% of protected areas were concentrated in the mountains, 0.24% in the agricultural lands, and 7.29% distributed in the lakes/rivers/costal areas. 5) As major improvement projects, proposed were: advancement of management systems for protected areas, expanded designation of protected areas, overhaul of managed areas, designation of protected areas for the protection of wild plants and fish, need for management measures for private property and the surrounding areas, need to secure appropriate management personnel and collaboration, locally-adapted management, eco-information-based management, total management of protected areas, etc.