• Journal of Korean Society of Rural Planning
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• v.3 no.2
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• pp.36-49
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• 1997

The drastic change of mountain community, which have led existing villages to a size reduction or an extinction, makes this study concentrate on finding out the new community unit as a spatial zone of dayily life and agricultural production. The communality which has played a key role in a aura settlement consistency has been focused on the socio-economic aspect till now, neglecting the spatia] nature. The settlement-communality( SC) putting a stress on the spatial aspect can be, therefore, shapec as being multi-dimensional, composed of both a horizontally areal coverage on the surface of the residential place and a vertically hierarchial relationship between settlements, by analyzing thro( elements of communality that are the economic, socio -cultural and spatial activities. The research site is located administratively in Milan-Myoun, Pyoungchang-Gun, Gangwon-Do that ha: the characteristics as a typical mountain community. The results of field survey of which the method i: to draw the activity zone from an interview with every village's head and some residents with th( prepared questionaire can be summarized as followings. Firstly, the SC in almost all villages tended to be weakened or extincted, none the less, the spatia zone of that overally enlarged and got out of natural village unit(hamlet). However the areal coverall on which the SC has an influence reaches up to the alliant domain of a few villages generally congruen with the lowest level administrative district, Secondly, the economic and social activity pattern in village life has a tendency to be directly linked with a upper central place, so that has induced the function of a central village in the middle-low settlement hierarchy to be largely shrinked. Not only the conventional residents'access to goods service but also the recent service-delivers'access to residents has gradually formed the vertical communality with direct linkage between the upper and the bottom level settlements Lastly, the enfeeblement of the SC in the lowest settlement level tends to be supplemented by enlarging the horizontal zone of the SC or especially by strengthening the vertical direct linkage system. The very this point makes the mountain community open to the external world and also makes the spatial unit of community be multi-dimensional just like a cubic.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.200-214
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• 1994

In order to clarify the benthic environmental properties as a part of a study on the macrobenthic community in the Chinhae Bay System, water temperature, salinity and dissolved oxygen (DO) in surface and bottom water layers, mean grain size (${\phi}$) and sediment organic carborn (SOC) in surface sediment were analyzed at twelve stations during the period from June 1987 to May 1990. A high sediment organic carbon and hypoxic condition in bottom water due to the development of summer stratification and fine sediment texture toward the inner bay were important environmental characteristics of Chinhae Bay. Hypoxic conditions began to develop in the inner bay from May, and gradually spread toward the outer bay in summer with a peak in September when half the bay was affected by this oxygen deficiency. Recovery from this hypoxic condition in the bottom layer was observed from the beginning of autumn together with a disappearance of the summer stratification. Principal component analyses were carried out from the following five environmental variables:mean water temperature, salinity, dissolved oxygen in the bottom layer and mean grain size, sediment organic carbon in surface sediment. The twelve stations were classified into four areal groups based on the analyses. The division of the areal groups had high correlations to the sediment organic carbon content.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.432-432
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• 2017

국내에서 설계홍수량 산정시, 실무 적용성이 높은 설계강우-유출 모형을 채택하고 유출모형으로는 단위도 방법을 적용하여 설계홍수량을 산정한다. 설계홍수량을 산정함에 있어 설계강우-유출관계 모형을 적용하기 위한 필수요소로 확률강우량 산정이 선행되어야 한다. 확률강우량은 유역면적이 25.9 m를 초과할 경우 면적평균확률강우량을 사용하여야하나 지점평균확률강우량을 주로 사용하고 있다. 이는 해당 유역 강우의 공간적 분포를 고려하고 있지 않기 때문에 각 강우관측소에서 관측되는 지점 강우자료를 면적평균확률강우량으로 산정하는데 매번 복잡한 자료처리과정을 거쳐야 하는데 있다. 따라서 비교적 산정이 간편한 지점평균확률강우량을 사용하여 면적평균확률강우량으로 손쉽게 전환할 수 있는 각 유역별 ARF(Areal Reduction Factor) 의 필요성이 대두된다.(이등, 정등 2002) 본 연구에서는 일반적으로 유역의 강우 빈도해석시 이용되는 면적고정형 방법을 사용하여 표본면적에 대하여, 설계홍수량 산정요령(국토부, 2012)에 제시 된 4대강 유역의 ARF와 제주도 한천유역의 수문학적 특성을 반영한 ARF를 산정하여 비교 하였다. 표본면적($100km^2$)에 대하여 기존 4대강 유역의 ARF와 본 연구에서 산정된 ARF 비교 결과 권역별, 빈도별, 지속시간에 따른 ARF는 제주 도심지 유역 기준 최대 18.63%(영산강유역) 작게 산정되었음을 확인하였다. 이러한 결과는 향후 해당유역의 수문학적 특성 미반영으로 인해 설계홍수량이 과다 및 과소 산정되어 안정적인 수공구조물 결정을 저해하는 중요 요소로 작용 될 수 있어 제주도 전 유역에 적용 가능한 ARF 산정 및 기준 설정 등의 조치가 요구된다.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3855-3863
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• 2022

An evaluation of the radiation shielding performance of high-Z-particle-loaded polylactic acid (PLA) composite materials was pursued. Specimens were produced via fused deposition modeling (FDM) using copper-PLA, steel-PLA, and BaSO₄-PLA composite filaments containing 82.7, 75.2, and 44.6 wt% particulate phase contents, respectively, and were tested under broad-band flash x-ray conditions at the Sandia National Laboratories HERMES III facility. The experimental results for the mass attenuation coefficients of the composites were found to be in good agreement with GEANT4 simulations carried out using the same exposure conditions and an atomistic mixture as a model for the composite materials. Further simulation studies, focusing on the Cu-PLA composite system, were used to explore a shield design parameter space (in this case, defined by Cu-particle loading and shield areal density) to assess performance under both high-energy photon and electron fluxes over an incident energy range of 0.5-15 MeV. Based on these results, a method is proposed that can assist in the visualization and isolation of shield parameter coordinate sets that optimize performance under targeted radiation characteristics (type, energy). For electron flux shielding, an empirical relationship was found between areal density (AD), electron energy (E), composition and performance. In cases where ${\frac{E}{AD}}{\geq}2MeV{\bullet}cm{\bullet}g^{-1}$, a shield composed of >85 wt% Cu results in optimal performance. In contrast, a shield composed of <10 wt% Cu is anticipated to perform best against electron irradiation when ${\frac{E}{AD}}<2MeV{\bullet}cm{\bullet}g^{-1}$.

• Transactions of the Society of Information Storage Systems
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• v.5 no.2
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• pp.70-75
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• 2009

Most hard disk drives uses load/unload technology because of benefits as like an increased areal density, a reduced power consumption and an improved shock resistance. However, ramp tilt induced by ramp manufacture and assembly causes mechanical problems such as unload fail in case of exceeding ramp tolerance. In this paper, we focus on experimental analysis for unloading characteristics affected by ramp tilt. We repeatedly perform load/unload test as 500,000 cycles for original model and ramp tilt model. This paper shows that it is possible to analyze unload characteristics through measuring scratch and wear of suspension lift-tab, ramp, suspension dimple-flexure and disk. We also identify structural relation between suspension lift-tab and ramp through scratch and wear of suspension lift-tab and ramp. As the result of measurement and analysis, we can investigate decrease of unloading performance in ramp tilt model.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.1
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• pp.120-132
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• 2022

Recently, the rapid increase in vacant houses in urban areas has caused various problems such as worsening urban landscape, causing safety accidents, crime accidents, and hygiene problems. According to the Statistics Korea Future Population Estimation results, the growth rate of Korean population and households is expected to continue to decrease, which is likely to lead to an increase in the occurrence of vacant houses. If the problem caused by the occurrence of vacant houses is neglected, it causes not only a physical decline such as a deterioration of the residential environment but also a social and economic decline. In order to solve this problem, it is necessary to grasp the spatial distribution characteristics of vacant houses at the local level considering the existence of regional characteristics and spatial influence. Therefore, in this study, in order to measure global spatial autocorrelation, the analysis was conducted centering on the old downtown area of Busan, where there are many vacant houses through Moran's I and Geographically Weighted Regression(GWR). In addition, the distribution of vacant houses in different spatial units in Eup_Myeon_Dong and Census was analyzed to evaluate the possibility of Modifiable Areal Unit Problem(MAUP), which differ in the results of spatial analysis as the spatial analysis units change. As a result of the analysis, the occurrence of vacant houses by Eup_Myeon_Dong in the old downtown area of Busan had spatial heterogeneity, and the spatial analysis results of vacant houses were different as the spatial analysis units were different. Accordingly, in order to understand the exact distribution characteristics of vacant house occurrence, spatial dimensions using the GWR model should be considered, and it is suggested that consideration of the MAUP is necessary.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.243-243
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• 2009

Bi2O3 doped ZnO nanostructures structure were successfully synthesized by a thermal evaporatiion process and their structural characteristics were investigated. It is demonstrated that the growth condition such as the areal density, pretreatment of the substrates and growth temperature have great influence on the morphology and the alignment of the nanorods arrays. The density of Bi2O3 doped ZnO nanostructures is controlled by the gold (Au) nanoparticle density deposited on the silicon substrates. Relatively homogenous size and shape were observed by introducing gold(Au) seed-layer as nucleation centers on the substrates prior to the VLS reaction. The samples were characterized by X-ray diffraction, scanning electron microscopy.

• Economic and Environmental Geology
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• v.33 no.1
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• pp.51-59
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• 2000

As a part of natural hazard assessment, regional slope stability analysis was conducted using Geoscientific Information System (GIS) in the northern area of Chungju Lake. Selected factors which affect the slope stability in the study area were lithology, soil, density of lineament, groundwater level, dip of slope, aspect of slope, and geological engineering properties. Geological structural domains were determined by collected data of joint orientation from about 200 sites in order to produce a slope instability map. Potential type of failure and its direction could be expected through the domains. And a slope instability map was produced, comparing the representative orientations of the domains with the orientations of the slopes which were made through TIN module in ARC/INFO. Under the consideration of environmental geological characteristics of the study area, rating and weighting of each factor of slope stability analysis were decided and spatial analysis of regional slope stability was couducted through overlaying technique of GIS. The result of areal distribution of slope stability showed that the most unstable area was the area between Mt. Pudae and Mt. Jubong, and the northern area of the railway station, Samtan.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.319-320
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• 2008

This paper introduces remote-sensing data which can be practically applied for offshore wind resource assessment. Development of offshore wind energy is inevitable for Korea to achieve the national dissemination target of renewable energy, i.e., 5% uptil 2010. However, the only available offshore in-situ measurement, marine buoy data would not represent areal wind characteristics. Consequently, remote-sensing technology has been started to apply to offshore wind resource assessment and is actively developing. Among them, NCAR/NCEP reanalysis dataset, QuikSCAT blended dataset, and offshore wind retrieval from SAR imagery are briefly summarized in this paper.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.198-203
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• 1998

This study, a sub-one of comprehensive research works titled under “Rural Resources Evaluation System”, tried to verify utility/applicability of the developed model system through the case study works on 3 sample villages, Backya, Uyan and Suyu, representing the lowland, upland and seashore villages respectively. From the various surveying and collecting works including the official/statistical data collection, map analysis, insitu investigation, field survey and written material review, the original data set were obtained and manipulated into final input data for resources grading. After then, by the automatized calculation procedure of “Rural Resources Evaluation System”, score results for resources evaluation were finally produced with the total maximum score being 1,000. Through comparing works among score results of 3 case villages and between score results and areal characteristics of each case village, the applicability of the system developed in this study was well confirmed.