• Journal of the Mineralogical Society of Korea
• /
• v.24 no.1
• /
• pp.31-36
• /
• 2011

Meteorites are extraterrestrial solid rock fragments that fell from the outer space. Investigating mineral magnetic properties of the Meteorites is essential in understanding the evolution of planets and asteroids in the Solar System. In particular, magnetic characterization of magnetic mineral can provide constraints on the progress of differentiation in ancient planetary bodies. In the present study, ratio of thermoremanent magnetization (TRM) over saturation isothermal remanent magnetization (SIRM) was applied to diagnose the magnetic minerals in meteorites and igneous rocks. Distinctive classification of TRM/SIRM suggests that kamacite, tetrataenite, magnetite, and (Cr,Ti)-rich iron oxide are responsible for the magnetization of H5 Richardton, LL6 St. Severin, ALH84001, and DaG476, respectively. The TRM/SIRM ratio could be an efficient tool in identifying magnetic minerals especially when rocks or meteorites contain unstable material under heating.

• 한국방재학회:학술대회논문집
• /
• 2011.02a
• /
• pp.112-112
• /
• 2011

오늘날 우리 사회의 생활과 문화의 질이 향상됨에 따라 공공 및 개인의 안전과 건강에 대한 관심이 증대되고 있다. 특히, 재난과 비상사태는 생명에 대한 희생뿐만 아니라 훨씬 더 심각한 경제적인 결과를 초래한다. 이러한 응급사태에 개비하여 적절히 준비되지 않았거나 재난의 예방 및 완화시킬 방법을 가지고 있지 못한다면 도시의 발전적인 프로젝트는 예고 없이 도시를 강타하는 재난 및 비상사태에 의해 무산되고 만다. 이러한 여건 하에 재난과 응급사고를 효율적으로 대처하는 응급처치와 서비스에 대한 급격한 관심과 함께 일정한 결정적 대응시간 내에 각종사고와 재해로부터 방어할 수 있는 공공서비스에 대한 필요성이 크게 증가되었다. 본 연구에서는 신고, 응급구조, 환자이송 등 도시의 병원 전 단계 의료환경에 대해서 조사하였다. 본 연구의 목적은 반응시간과 출동거리를 분석함으로써, 응급사고에 즉시 응급구조서비스를 제공하기 위해 안전센터(119센터)의 최적 입지를 확인하는 것이다. 이를 위해서 사고발생, 반응시간, 출동거리 등을 응급의료 활동과 관련된 연구논문, 대상지 전역의 소방기록물과 출동일지 등의 통계자료를 활용하여 신속한 응급의료 서비스를 위한 패턴을 분석 하였다. 또한 응급구조대의 조직과 활동의 분석을 통해 응급의료시설의 최적 입지설정을 위한 제도적 개선대안을 마련해 보았다. 대상지 연구를 위해, 구조활동 및 소방서비스의 최근 통계자료의 조사를 통해 진주시의 모든 119센터의 입지와 응급의료서비스 및 사고발생 현황을 나타내었다. 자료 분석을 위해서 SPSS14.0을 사용하였으며, 지역의 특성 분포, 안전센터별 대응시간, 이송시간 등을 소방 GPS시스템과 입지할당모형 중 Center Point Model(CPM)을 적용하였다. 결과적으로 본 연구를 통해 대상지역의 119안전센터의 서비스 질이 나쁜 지역을 지리학적인 관점에서 최적 입지/배분 패턴의 설정을 통해 확인할 수 있었으며, 이를 통해 미래 응급의료서비스의 효율적인 입지/배분을 통해 공공 및 개인의 안전과 건강에 기여할 수 있을 것으로 기대된다.

• 한국HCI학회:학술대회논문집
• /
• 2008.02a
• /
• pp.749-753
• /
• 2008

Proprioception defined it as the ability to detect, the spatial position or movement of joints using balance, power of the muscle, agility in the internal parts of the body. In existing study for improvement of proprioception, reaching task training provided a feedback; the assessment was not provided a feedback. But, this has problem that it can not guide a proprioception from situation with visual feedback. Virtual reality technique can solve the problem of way providing feedback during training. In this study, we developed proprioception training program using virtual reality and pilot study is performed. VR task were composed three modes. In mode 1, real-time movement of the body was provided using visual feedback. In mode 2, body position was provided using visual feedback when participant have specific response. And in mode 3, body position was not provided. VR task is performed five sessions at each mode and one session performed one by one a three target. In the result of this study, the moving time toward the target from mode 3 was smaller than the moving time toward the target from mode 1 (p= 0.001). The correlation was statistically significant between mode 2 and mode 3 while be offering visual feedback position of mode 2 1session. But, the correlation was not statistically significant between mode 2 and mode 3 after be offered visual feedback position of mode2 1session (p = 0.012). Training environment of mode 1 shows which training used visual feedback than proprioception. Mode2 can execute training of proprioception because first session acquires visual feedback by proprioception. The next study will be verification of the system for training or assessment by clinical experiment.

• Korean Journal of Soil Science and Fertilizer
• /
• v.22 no.3
• /
• pp.163-172
• /
• 1989

In order to study spatial variability of soil physical properties accross the land-partitioned boundary on Hwadong silt clay loam soil (Fine clayey, mixed, mesic family of Aquic Hapludalfs), all measured data were analyzed by means of kriging, fractile diagram, smooth frequency distribution, and autocorrelation. Sampling for soil particle size distribution analysis was made at 225 intersections of $15{\times}15$ grid with 10m interval. Field capacity, bulk density and saturated hydraulic conductivity were measured in situ at 594 intersections of $33{\times}18$ grid with 2.5m interval in only $6,000m^2$ reselected from $22,500m^2$ of sampling area for particle size distribution analysis. Sampled or measured soil depths were 0 to 10cm 25 to 35cm and 50 to 60cm at each intersections. The results are summarized as follows: 1. The coefficient of variance (CV) of various physical properties ranges from 4.8 to 128.8%. Saturated hydraulic conductivity is classified into the high variation group with CV greater than 100%, while the low variation group with CV smaller than 10% consists of bulk density. Other properties belong to the medium variation group with CV between 10 and 100%. 2. The appropriate number of soil samples for the determination of various physical properties with error smaller than 10% are calculated as one for bulk density, six for field moisture capacity, 16 for silt, 19 for clay, 69 for sand and 686 for saturated hydraulic conductivity. 3. Smooth frequency distribution and fractile diagram show that saturated hydraulic conductivity is in lognormal distribution while other physical properties are in normal distribution. 4. Serial correlation analysis reveals that the soil physical properties have spatial dependence between two nearest neighbouring grid points. Autocorrelation analysis of physical properties measured between the serial grid points in the direction of south to north following section boundary shows that the zone of influence showing stationarity ranges from 7.5 to 40m. In the direction of east to west across section boundary, the autocorrelogram of many physical properties shows peaks with the periodic interval of 30m, which are similar to the partitioned land width. This reveals that the land-partitioned boundary causes soil variability.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.43 no.2
• /
• pp.175-185
• /
• 2023

As drought risk increases due to climate change, various research works are underway around the world to respond to drought so as to minimize drought damage. In particular, in recent years, many studies are focused on analyzing regional patterns of drought in a comprehensive manner, however there is still insufficient to quantitatively identify drought-risk areas in a large river basin considering climate change in Korea. In this study, we calculated the Standardized Precipitation Index (SPI) and the Modified Standardized Precipitation Index (M_SPI) as representative meteorological drought index, and performed spatial autocorrelation analysis to identify the drought hotspot region under climate change scenarios of Representative Concentration Pathway (RCP) 4.5 and RCP 8.5. The SPI was calculated by estimating parameters for each observation station within the study area, whereas the M_SPI was calculated by estimating parameters for the entire study area. It is more reasonable to use the M_SPI for assessing meteorological drought from an overall perspective within the study area. When the M_SPI was used, long-term droughts showed drought hotspot areas clearly larger than short-term droughts. In addition, the drought hotspot area moved from the center of the Nakdong River basin to the Seomjin River basin over time. Especially, the moving patterns of the short-term/long-term drought were apparent under the RCP 4.5, whereas the moving patterns of the long-term drought were distinct under the RCP 8.5 scenarios.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.23 no.4
• /
• pp.251-267
• /
• 2021

Remotely sensed vegetation indices (VIs) are empirically related with gross primary productivity (GPP) in various spatio-temporal scales. The uncertainties in GPP-VI relationship increase with temporal resolution. Uncertainty also exists in the eddy covariance (EC)-based estimation of GPP, arising from the partitioning of the measured net ecosystem CO2 exchange (NEE) into GPP and ecosystem respiration (RE). For two forests and two agricultural sites, we correlated the EC-derived GPP in various time scales with three different near-surface remotely sensed VIs: (1) normalized difference vegetation index (NDVI), (2) enhanced vegetation index (EVI), and (3) near infrared reflectance from vegetation (NIRv) along with NIRvP (i.e., NIRv multiplied by photosynthetically active radiation, PAR). Among the compared VIs, NIRvP showed highest correlation with half-hourly and monthly GPP at all sites. The NIRvP was used to test the reliability of GPP derived by two different NEE partitioning methods: (1) original KoFlux methods (GPP_Ori) and (2) machine-learning based method (GPP_ANN). GPP_ANN showed higher correlation with NIRvP at half-hourly time scale, but there was no difference at daily time scale. The NIRvP-GPP correlation was lower under clear sky conditions due to co-limitation of GPP by other environmental conditions such as air temperature, vapor pressure deficit and soil moisture. However, under cloudy conditions when photosynthesis is mainly limited by radiation, the use of NIRvP was more promising to test the credibility of NEE partitioning methods. Despite the necessity of further analyses, the results suggest that NIRvP can be used as the proxy of GPP at high temporal-scale. However, for the VIs-based GPP estimation with high temporal resolution to be meaningful, complex systems-based analysis methods (related to systems thinking and self-organization that goes beyond the empirical VIs-GPP relationship) should be developed.

• Management & Information Systems Review
• /
• v.37 no.3
• /
• pp.27-47
• /
• 2018

In this study, we examine how land use zoning affects the land price controlling other variables such as road-facing condition of the land, land form, land age after its development and land size. We employ geographically weighted regression analysis which reflects spatial dependency as methodology with a data sample of land transaction price data of Jangyu, a new town, in Korea. The results of our empirical analysis show that the respective coefficients of traditional regression and geographically weighted regression are not significantly different. However, after calculating Moran's Index with residuals of both OLS and GWR models, we find that Moran's Index of GWR decreases around 26% compared to that of OLS model, thus improving the problem of spatial autoregression of residuals considerably. Unlike our expectation, though, in both traditional regression and geographically weighted regression where residential exclusive area is used as a reference variable, the dummy variable of the residential land for both housing and shops shows a negative sign. This may be because the residential land for both housing and shops is usually located in the level area while the residential exclusive area is located at the foot of a mountain or on a gentle hill where the residents can have good quality air and scenery. Although the utility of the residential land for both housing and shops is higher than its counterpart's since it has higher floor area ratio, amenity which can be explained as high quality of air and scenery in this study seems to have higher impact in purchase of land for housing. On the other hand, land for neighbourhood living facility seems to be valued higher than any other land zonings used in this research since it has much higher floor area ratio than the two land zonings above and can have a building with up to 5 stories constructed on it. With regard to road-facing condition, land buyers seem to prefer land which faces a medium-width road as expected. Land facing a wide-width road may have some disadvantage in that it can be exposed to noise and exhaust gas from cars and that entrance may not be easy due to the high speed traffic of the road. In contrast, land facing a narrow road can be free of noise or fume from cars and have privacy protected while it has some inconvenience in that entrance may be blocked by cars parked in both sides of the narrow road. Finally, land age variable shows a negative sign, which means that the price of land declines over time. This may be because decline of the land price of Jangyu was bigger than that of other regions in Gimhae where Jangyu, a new town, also belong, during the global financial crisis of 2008.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.18 no.2
• /
• pp.174-189
• /
• 2015

The objective of this study was to reconstruct spatial information using the results of the investigation and evaluation of the health of the living organisms, habitat, and water quality at the investigation points for the aquatic ecosystem health of the Nakdong River basin, to support the rational decision making of the aquatic ecosystem preservation and restoration policies of the Nakdong River basin using spatial analysis techniques, and to present efficient management methods. To analyze the aquatic ecosystem health of the Nakdong River basin, punctiform data were constructed based on the position information of each point with the aquatic ecosystem health investigation and evaluation results of 250 investigation sections. To apply the spatial analysis technique, the data need to be reconstructed into areal data. For this purpose, spatial influence and trends were analyzed using the Kriging interpolation(ArcGIS 10.1, Geostatistical Analysis), and were reconstructed into areal data. To analyze the spatial distribution characteristics of the Nakdong River basin health based on these analytical results, hotspot(Getis-Ord Gi, $G^*_i$), LISA(Local Indicator of Spatial Association), and standard deviational ellipse analyses were used. The hotspot analysis results showed that the hotspot basins of the biotic indices(TDI, BMI, FAI) were the Andong Dam upstream, Wangpicheon, and the Imha Dam basin, and that the health grades of their biotic indices were good. The coldspot basins were Nakdong River Namhae, the Nakdong River mouth, and the Suyeong River basin. The LISA analysis results showed that the exceptional areas were Gahwacheon, the Hapcheon Dam, and the Yeong River upstream basin. These areas had high bio-health indices, but their surrounding basins were low and required management for aquatic ecosystem health. The hotspot basins of the physicochemical factor(BOD) were the Nakdong River downstream basin, Suyeong River, Hoeya River, and the Nakdong River Namhae basin, whereas the coldspot basins were the upstream basins of the Nakdong River tributaries, including Andong Dam, Imha Dam, and Yeong River. The hotspots of the habitat and riverside environment factor(HRI) were different from the hotspots and coldspots of each factor in the LISA analysis results. In general, the habitat and riverside environment of the Nakdong River mainstream and tributaries, including the Nakdong river upstream, Andong Dam, Imha Dam, and the Hapcheon Dam basin, had good health. The coldspot basins of the habitat and riverside environment also showed low health indices of the biotic indices and physicochemical factors, thus requiring management of the habitat and riverside environment. As a result of the time-series analysis with a standard deviation ellipsoid, the areas with good aquatic ecosystem health of the organisms, habitat, and riverside environment showed a tendency to move northward, and the BOD results showed different directions and concentrations by the year of investigation. These aquatic ecosystem health analysis results can provide not only the health management information for each investigation spot but also information for managing the aquatic ecosystem in the catchment unit for the working research staff as well as for the water environment researchers in the future, based on spatial information.

• Journal of Korean Society of Forest Science
• /
• v.90 no.4
• /
• pp.565-572
• /
• 2001

The spatial genetic structure of Needle fir(Abies holophylla Max.) seedlings on forest gap within a Needle fir forest at Mt. Odae in Korea was analyzed on the basis of ISSR(inter-simple sequence repeats) marker analysis. The gap size was $1,500m^2(50m{\times}30m)$, and we sampled 416 one- or two-year-old seedlings by 2m intervals. Some trees at the upper crown layer except Needle firs and all trees at the middle and lower crown layers were removed, and Needle firs at the upper crown layer showed very weak growth strength or to be withering to death. The results of spatial autocorrelation using 31 polymorphic ISSR markers revealed that it was genetically homogeneous within spatial distance of 15.6m and the randomness of genetic distribution was from 15.6m to 31.2m. The genetic patch size of seedlings in forest gap might be restricted by the density of mother trees, making allow for the average height of adult Needle firs, the seed dispersal area, and the average distance between adults. For the directionality of seedling distribution, we investigated the variography using 'genetic configuration' which was the value of configuration in Multidimensional Scaling by genetic distance. In directional variogram, the increment of spatial distance from East to West direction was inversely proportional to genetic homogeneity. We presumed that this anisotrophy of seedling distribution at this forest gap resulted from the directionality of seed dispersal rather than the difference of fecundity between mother trees or the microhabitat variation, taking the evenness of forest floor condition, a vast seed production and the random distribution of seedlings at the studied site into consideration.

• International Area Studies Review
• /
• v.21 no.4
• /
• pp.159-172
• /
• 2017

In a typical trend-cycle decomposition of GDP, the trend component is usually assumed to follow a random walk process. This paper considers an ARIMA trend and assesses the validity of the ARIMA trend model. I construct univariate and bivariate unobserved-components(UC) models, allowing the ARIMA trend. Estimation results using U.S. data are favorable to the ARIMA trend models. I, also, compare the forecasting performance of the UC models. Dynamic pseudo-out-of-sample forecasting exercises are implemented with recursive estimations. I find that the bivariate model outperforms the univariate model, the smoothed estimates of trend and cycle components deliver smaller forecasting errors compared to the filtered estimates, and, most importantly, allowing for the ARIMA trend can lead to statistically significant gains in forecast accuracy, providing support for the ARIMA trend model. It is worthy of notice that trend shocks play the main source of the output fluctuation if the ARIMA trend is allowed in the UC model.