• Journal of the Korean Association of Geographic Information Studies
• /
• v.27 no.3
• /
• pp.76-86
• /
• 2024

This study sought to introduce smart urban regeneration to solve the problem of aging and substandard housing in large cities that occurred during the rapid industrialization and urbanization of local cities in Korea. Accordingly, this study aims to activative the old downtown through the convergence of the existing urban regeneration project and smart city project and to improve the physical, social, and economic aspects. As a research method, the literature related to smart cities and urban regeneration was systematically reviewed, and the possibility of introducing smart city services in the Samho-dong district of Yangsan City was explored through domestic and foreign case analysis. As a result of the research, the necessity of smart urban regeneration was highlighted, and the conclusion was reached that it is important to improve the efficiency of urban regeneration projects by using information and communication technology and strengthen sustainability by urban regeneration. This study is expected to contribute to the activative the old downtown and the improvement of the quality of life of citizens, and it is necessary to strengthen the interaction between smart city and urban regeneration in the future, and the introduction of smart city services suitable for local characteristics is judged to play an important role in sustainable urban development through local community and citizen participation.

• Spatial Information Research
• /
• v.11 no.3
• /
• pp.261-274
• /
• 2003

The effective probability-based tile pre-fetching algorithm and the collaborative cache replacement algorithm are able to reduce the response time for user's requests by transferring tiles which will be used in advance and determining tiles which should be removed from the restrictive cache space of a client based on the future access probabilities in Web GISs(Geographical Information Systems). The Web GISs have multi-level abstracted data for the quick response time when zoom-in and zoom-out queries are requested. But, the previous pre-fetching algorithm is applied on only two-dimensional pre-fetching space, and doesn't consider expanded pre-fetching space for multi-level abstracted data in Web GISs. In this thesis, a probability-based pre-fetching algorithm for multi-level abstracted in Web GISs was proposed. This algorithm expanded the previous two-dimensional pre-fetching space into three-dimensional one for pre-fetching tiles of the upper levels or lower levels. Moreover, we evaluated the effect of the proposed pre-fetching algorithm by using a simulation method. Through the experimental results, the response time for user requests was improved 1.8%∼21.6% on the average. Consequently, in Web GISs with multi-level abstracted data, the proposed pre-fetching algorithm and the collaborative cache replacement algorithm can reduce the response time for user requests substantially.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.14 no.3
• /
• pp.132-141
• /
• 2012

Climate change impact assessment of cereal crop production in South Korea was performed using land attributes and daily weather data at a farm scale as inputs to crop models. Farmlands in South Korea were grouped into 68 crop-simulation zone units (CZU) based on major mountains and rivers as well as existing land use information. Daily weather data at a 1-km grid spacing under the A1B- and RCP8.5 scenarios were generated stochastically to obtain decadal mean of daily data. These data were registered to the farmland grid cells and spatially averaged to represent climate conditions in each CZU. Monthly climate data for each decade in 2001~2100 were transformed to 30 sets of daily weather data for each CZU by using a stochastic weather generator. Soil data and crop management information for 68 CZU were used as inputs to the CERES-rice, CERE-barley and CROPGRO-soybean models calibrated to represent the genetic features of major domestic cultivars in South Korea. Results from the models suggested that the heading or flowering of rice, winter barley and soybean could be accelerated in the future. The grain-fill period of winter barley could be extended, resulting in much higher yield of winter barley in most CZUs than that of rice. Among the three major cereal grain crops in Korea, rice seems most vulnerable to negative impact of climate change, while little impact of climate change is expected on soybeans. Because a positive effect of climate change is projected for winter barley, policy in agricultural production should pay more attention to facilitate winter barley production as an adaptation strategy for the national food security.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.27 no.2
• /
• pp.78-95
• /
• 2024

For the establishment and comparison of environmental plans across various domains, considering climate change and urban issues, it is crucial to build spatial data at the regional scale classified with consistent criteria. This study mapping the Local Climate Zone (LCZ) of Changwon City, where active climate and environmental research is being conducted, using the protocol suggested by the World Urban Database and Access Portal Tools (WUDAPT). Additionally, to address the fragmentation issue where some grids are classified with different climate characteristics despite being in regions with homogeneous climate traits, a filtering technique was applied, and the LCZ classification characteristics were compared according to the filtering radius. Using satellite images, ground reference data, and the supervised classification machine learning technique Random Forest, classification maps without filtering and with filtering radii of 1, 2, and 3 were produced, and their accuracies were compared. Furthermore, to compare the LCZ classification characteristics according to building types in urban areas, an urban form index used in GIS-based classification methodology was created and compared with the ranges suggested in previous studies. As a result, the overall accuracy was highest when the filtering radius was 1. When comparing the urban form index, the differences between LCZ types were minimal, and most satisfied the ranges of previous studies. However, the study identified a limitation in reflecting the height information of buildings, and it is believed that adding data to complement this would yield results with higher accuracy. The findings of this study can be used as reference material for creating fundamental spatial data for environmental research related to urban climates in South Korea.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.6
• /
• pp.430-438
• /
• 2009

An attempt was made to establish the suitability classes of lands for the cultivation of ginseng(Panax ginseng C. A. Meyer). For this study, the relationships between various soil characteristics and ginseng yields were investigated on altogether 450 ginseng fields (150 sites in paddy and 300 sites in upland), across Kangwon, Kyunggi, Chungbug, Chungnam, Jonbug and Kyungbug Provinces, where ginseng is widely cultivated. In the paddy fields, most influential properties of soil on the ginseng yields was found to be the drainage class. Texture of surface soil and available soil depths affected the ginseng yields to some extents. However, the topography, slope, and the gravel content were found not to affect the ginseng yields. In the uplands, the texture of surface soil was most influential and the topography, slope, and occurrence depth of hard-pan were least influential on the performance of the crop. Making use of multiple regression, by SAS, the contribution of soil morphological and physical properties such as, topography, surface soil texture, drainage class, slope, available soil depth, gravel content, and appearance depth of hard-pan, for the suitability of land for ginseng cultivation was analyzed. Based on the results of above analysis, adding up all of the suitability indices, land suitability classes for ginseng cultivation were proposed. On top of this, taking the weather conditions into consideration, suitability of land for ginseng cultivation was established in paddy field and in uplands. As an example, maps showing the distribution of suitable land for ginseng cultivation were drawn, adopting the land suitability classes obtained through current study, soil map, climate map, and GIS information, for Eumsung County, Chungbug Province. Making use of the information on the land suitability for ginseng cultivation obtained from current study, the suitability of lands currently under cultivation of ginseng was investigated. The results indicate that 74.0% of them in paddy field and 88.3% in upland are "highly suitable" and "suitable".

• Journal of KIISE:Databases
• /
• v.32 no.4
• /
• pp.345-361
• /
• 2005

A transform-space index indexes objects represented as points in the transform space An advantage of a transform-space index is that optimization of join algorithms using these indexes becomes relatively simple. However, the disadvantage is that these algorithms cannot be applied to original-space indexes such as the R-tree. As a way of overcoming this disadvantages, the authors earlier proposed the transform-space view join algorithm that joins two original- space indexes in the transform space through the notion of the transform-space view. A transform-space view is a virtual transform-space index that allows us to perform join in the transform space using original-space indexes. In a transform-space view join algorithm, the order of accessing disk pages -for which various space filling curves could be used -makes a significant impact on the performance of joins. In this paper, we Propose a new space filling curve called the adaptive row major order (ARM order). The ARM order adaptively controls the order of accessing pages and significantly reduces the one-pass buffer size (the minimum buffer size required for guaranteeing one disk access per page) and the number of disk accesses for a given buffer size. Through analysis and experiments, we verify the excellence of the ARM order when used with the transform-space view join. The transform-space view join with the ARM order always outperforms existing ones in terms of both measures used: the one-pass buffer size and the number of disk accesses for a given buffer size. Compared to other conventional space filling curves used with the transform-space view join, it reduces the one-pass buffer size by up to 21.3 times and the number of disk accesses by up to $74.6\%$. In addition, compared to existing spatial join algorithms that use R-trees in the original space, it reduces the one-pass buffer size by up to 15.7 times and the number of disk accesses by up to $65.3\%$.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.7 no.2
• /
• pp.132-140
• /
• 2005

This study was conducted to develop regional site index equations for main tree species in Gangwon, Gyunggi-Chungcheong, Gyungsang, and Jeolla area of Korea, using environmental and soil factors obtained from a digital forest site map. Using the large data set obtained from the digital forest map, a total of 28 environmental and soil factors were regressed on site index by tree species for developing the best site index equations for each of the regions. The selected main tree species were Larix 1eptolepis, Pinus koraiensis, Pinus densiflora, Pinus thunbergii, and Quercus acutissima. Finally, four to five environmental and soil factors by species were chosen as independent variables in defining the best regional site index equations with the highest coefficients of determination $(R^2)$. For those site index equations, three evaluation statistics such as mean difference, standard deviation of difference and standard error of difference were applied to the data sets independently collected from fields within the region. According to the evaluation statistics, it was found that the regional site index equations by species developed in this study conformed well to the independent data set, having relatively low bias and variation. It was concluded that the regional site index equations by species had sufficient capability for the estimation of site productivity.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.2 no.2
• /
• pp.47-61
• /
• 2000

Agroclimatic zoning was done for paddy rice culture in North Korea based on a simulation experiment. Daily weather data for the experiment were generated by 3 steps consisting of spatial interpolation based on topoclimatological relationships, zonal summarization of grid cell values, and conversion of monthly climate data to daily weather data. Regression models for monthly climatological temperature estimation were derived from a statistical procedure using monthly averages of 51 standard weather stations in South and North Korea (1981-1994) and their spatial variables such as latitude, altitude, distance from the coast, sloping angle, and aspect-dependent field of view (openness). Selected models (0.4 to 1.6$^{\circ}C$ RMSE) were applied to the generation of monthly temperature surface over the entire North Korean territory on 1 km$\times$l km grid spacing. Monthly precipitation data were prepared by a procedure described in Yun (2000). Solar radiation data for 27 North Korean stations were reproduced by applying a relationship found in South Korea ([Solar Radiation, MJ m$^{-2}$ day$^{-1}$ ] =0.344 + 0.4756 [Extraterrestrial Solar Irradiance) + 0.0299 [Openness toward south, 0 - 255) - 1.307 [Cloud amount, 0 - 10) - 0.01 [Relative humidity, %), $r^2$=0.92, RMSE = 0.95 ). Monthly solar irradiance data of 27 points calculated from the reproduced data set were converted to 1 km$\times$1 km grid data by inverse distance weighted interpolation. The grid cell values of monthly temperature, solar radiation, and precipitation were summed up to represent corresponding county, which will serve as a land unit for the growth simulation. Finally, we randomly generated daily maximum and minimum temperature, solar irradiance and precipitation data for 30 years from the monthly climatic data for each county based on a statistical method suggested by Pickering et a1. (1994). CERES-rice, a rice growth simulation model, was tuned to accommodate agronomic characteristics of major North Korean cultivars based on observed phenological and yield data at two sites in South Korea during 1995~1998. Daily weather data were fed into the model to simulate the crop status at 183 counties in North Korea for 30 years. Results were analyzed with respect to spatial and temporal variation in yield and maturity, and used to score the suitability of the county for paddy rice culture.

• Korean Journal of Ecology and Environment
• /
• v.43 no.1
• /
• pp.44-54
• /
• 2010

In this study, a comprehensive exploration and evaluation of washland candidate locations by means of field monitoring as well as spatial analysis in six major river system (Han, Nakdong, Nam, Geum, Youngsan, and Seomjin Rivers). Washland(in other words, river detention basin) is an artificial wetland system which is connected to streams or rivers likely to riverine wetlands. Major purpose of washland creation is to control floodings, water supply and purification, providence of eco-cultural space to human and natural populations. Characteristics and functions of riverine wetlands can be expected as well, thus it is believed to be an efficient multi-purpose water body that is artificially created, in terms of hydrology and ecology. Geographical information and field monitoring results for the washland candidate locations were evaluated in 2009, with respect to optimal location exploration, ecosystem connectivity and educational-cultural circumstances. A total of $269\;km^2$ washland candidate locations were found from spatial analysis (main channel of Rivers South Han, 71.5; Nakdong 54.1; Nam, 2.3; Geum, 79.0; Youngsan 46.4; Seomjin 15.7), and they tended to be distributed in mid- to lower part of the rivers to which tributaries are confluent. Field monitoring at 106 sites revealed that some sites located in the Rivers Nam and Geum is appropriate for restoration or artificial creation as riverine wetlands. Several sites in the Nakdong and Seomjin Rivers were close to riverine wetlands (e.g., Upo), habitats of endangered species (e.g., otters), or adjacent to educational facility (e.g., museums) or cultural heritages (e.g., temples). Those sites can be utilized in hydrological, ecological, educational, and cultural ways when evidence of detailed hydrological evaluation is provided. In conclusion, determination of washland locations in the major river basins has to consider habitat expansion as well as hydrological function (i.e. flood control) basically, and further utility (e.g. educational function) will increase the values of washland establishment.

• Korean Journal of Environment and Ecology
• /
• v.30 no.2
• /
• pp.173-184
• /
• 2016

Knowledge of the relationships among interspecific competition, spatial distributions and ecological niches plays an important role in understanding biogeographical distribution patterns of species. In this study, the distributional characteristics and ecological niches of the three Viperidae species (Gloydius ussuriensis, G. brevicaudus, and G. saxatilis) in South Korea were determined based on observation data and species distribution model. The effects of interspecific competition on geographical distribution and the division of the ecological niches of the vipers were also examined based on the models of predicted species distribution. The results showed that altitude was the most important environmental variable for their distribution, and the altitudes at which these snakes were distributed correlated with the climate of that region. Although interspecific ecological niches are quite overlapped, their predicted distribution patternsvary by the Taebaek Mountains. When overlaying the distribution models, most of the overlapping habitats were forest areas, which were relatively less overlapped than were the entire research areas. Thus, a parapatric distribution pattern was expected. The abundance of species occurring sympatrically was positively correlated with each other, indicating the lack of serious interspecies competition in this region. In conclusion, although the three Viperidae species in South Korea occupy similar ecological niches, these snakes exhibit parapatric distribution patterns without direct competition. Further research on various geographic variables (e.g., altitude, microhabitat characteristics) using relatively fine grid sizes, as well as further detailed ecological and behavioral research, is needed to determine the causative factors for the parapatric distribution pattern.