• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.82-88
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• 2014

Purpose: The purpose of study was to evaluate radiation dose for pediatric patients by changing tube voltage (kVp) and tube current (mA) at minimum conditions. By evaluating radiation dose, we want to provide dose reduction for pediatric patients and maintain good quality of SPECT/CT images. Materials and Methods: Discovery NM/CT 670 Scanne was used as SPECT/CT. Tube voltages are 80 and 100 kvP. Tube currents are 10, 15, 20, 25 mA. Using PMMA (Polymethyl methacrylate) Phantom, radiation dose which were calculated at center and peripheral dose and SNRD (Signal to Noise Ratio Dose) were evaluated. Using the CT performance phantom, spatial resolution was evaluated as the MTF (Modulation Transfer Function) graph. Jaszczak phantom was used for SPECT image evaluation by CNR (Contrast to Noise to Ratio). Results: Radiation dose using the PMMA phantom was higher peripheral dose than center dose about 7%. SNRD were 7.8, 8.2, 8.3, 8.8, 8.8, 9.9, 9.8, 9.6 for 80 kVp 10, 15, 20, 25 mA, 100 kVp 10, 15, 20, 25 mA. We can distinguish 35, 45, 70, 71, 52, 58, 90, 110 linepair for 80 kVp 10, 15, 20, 25 mA, 100 kVp 10, 15, 20, 25 mA at resolution with MTF. CNR of SPECT images using CT attenuation map were 57.8, 57.7, 57.1, 56.7, 56.6, 56.7, 56.7, 56.7% for 80 kVp 10, 15, 20, 25 mA, 100 kVp 10, 15, 20, 25 mA. Conclusion: In this study, radiation dose for pediatric patients showed decreased low dose condition. And SNRD value was similar in all condition. Resolution showed higher value at 100kVp than 80kVp. for CNR, there was no significant difference. we should take additional study to prove better quality and dose reduction.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.12a
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• pp.169-181
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• 2004

SK Telecom has already constructed GIMS system as the base common framework of LBS/GIS service system based on OGC(OpenGIS Consortium)'s international standard for the first mobile vector map service in 2002, But as service content appears more complex, renovation has been needed to satisfy multi-purpose, multi-function and maximum efficiency as requirements have been increased. This research is for preparation ion of GML3-based platform to upgrade service from GML2 based GIMS system. And with this, it will be possible for variety of application services to provide location and geographic data easily and freely. In GML 3.0, it has been selected animation, event handling, resource for style mapping, topology specification for 3D and telematics services for mobile LBS multimedia service. And the schema and transfer protocol has been developed and organized to optimize data transfer to MS(Mobile Stat ion) Upgrade to GML 3.0-based GIMS system has provided innovative framework in the view of not only construction but also service which has been implemented and applied to previous research and system. Also GIMS channel interface has been implemented to simplify access to GIMS system, and service component of GIMS internals, WFS and WMS, has gotten enhanded and expanded function.

• Korean Journal of Ecology and Environment
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• v.49 no.1
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• pp.42-50
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• 2016

The purpose of this study is to set the direction to manage national parks to cope with climate change, and offer basic data to establish the relevant policies. Towards this end, this study analyzed the current and future climate change vulnerability of national parks using the 24 proxy variables of vulnerability in the LCCGIS program, a tool to evaluate climate change vulnerability developed by the National Institute of Environmental Research. To analyze and evaluate the current status of and future prospect on climate change vulnerability of national parks, the proxy variable value of climate exposure was calculated by making a GIS spatial thematic map with $1km{\times}1km$ grid unit through the application of climate change scenario (RCP8.5). The values of proxy variables of sensitivity and adaptation capability were calculated using the basic statistics of national parks. The values of three vulnerability evaluation items were calculated regarding the present (2010s) and future (2050s). The current values were applied to the future equally under the assumption that the current state of the proxy variables related to sensitivity and adaptation capability without a future prediction scenario continues. Seoraksan, Odaesan, Jirisan and Chiaksan National Parks are relatively bigger in terms of the current (2010s) climate exposure. The national park, where the variation of heat wave is the biggest is Wolchulsan National Park. The biggest variation of drought occurs to Gyeryongsan National Park, and Woraksan National Park has the biggest variation of heavy rain. Concerning the climate change sensitivity of national parks, Jirisan National Park is the most sensitive, and adaptation capability is evaluated to be the highest. Gayasan National Park's sensitivity is the lowest, and Chiaksan National Park is the lowest in adaptation capability. As for climate change vulnerability, Seoraksan, Odaesan, Chiaksan and Deogyusan National Parks and Hallyeohaesang National Park are evaluated as high at the current period. The national parks, where future vulnerability change is projected to be the biggest, are Jirisan, Woraksan, Chiaksan and Sobaeksan National Parks in the order. Because such items evaluating the climate change vulnerability of national parks as climate exposure, sensitivity and adaptation capability show relative differences according to national parks' local climate environment, it will be necessary to devise the adaptation measures reflecting the local climate environmental characteristics of national parks, rather than establishing uniform adaptation measures targeting all national parks. The results of this study that evaluated climate change vulnerability using climate exposure, sensitivity and adaptation capability targeting Korea's national parks are expected to be used as basic data for the establishment of measures to adapt to climate change in consideration of national parks' local climate environmental characteristics. However, this study analyzed using only the proxy variables presented by LCCGIS program under the situation that few studies on the evaluation of climate change vulnerability of national parks are found, and therefore this study may not reflect overall national parks' environment properly. A further study on setting weights together with an objective review on more proper proxy variables needs to be carried out in order to evaluate the climate change vulnerability of national parks.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.162-176
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• 2016

The experience and play activities in forest spaces have played an effective role in children's growth and development, therefore, many studies and projects related to forest activity space have progressed actively. However, the focus of previous research has been merely on the effectiveness of forest activity but little on providing the basis for the spatial design of these types of forest activity spaces. Thus, this study aims to identify the relationship between children's developmental play activity and the physical characteristics of forest activity spaces for evidence-based design. First of all, indicators for Cognitive-Social play(CSP) was selected and forest spaces were categorize into play facility spaces and forest spaces. More detailed environmental characteristics of each space were 'play area' and 'paving materials' for play facilities and 'density of tree and shrub', 'slope', 'paving materials' and 'fixing and type of natural loose parts' for forest space. Through environmental inventory and behavior observation, the types of play behaviors and the occurrence frequency of children aged four to five were collected and analyzed. The results were as follows: 1) In play facility spaces, play behaviors occurred at a high frequency at the facility playground with play facilities and sand area. In terms of CSP, functional-solitary and functional-parallel plays occurred predominantly. 2) In forest spaces, various play behaviors occurred at high frequency in the environment with low density planting and various natural loose parts. For CSP, functional-group and symbolic-group plays occurred at a high frequency. 3) Symbolic-group play appeared to be highly affected by environmental characteristics like tree area of scatter density or less, 10~20 degree slope, and the presence of fixed large stumps. In conclusion, this study provides standards of physical environmental characteristics for forest activity space design through direct observation and analysis of children's play behaviors.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.4
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• pp.121-131
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• 2008

This study was conducted to delineate temporal and spatial patterns of potential risk of cold injury by combining the short-term cold hardiness of Campbell Early grapevine and the IPCC projected climate winter season minimum temperature at a landscape scale. Gridded data sets of daily maximum and minimum temperature with a 270m cell spacing ("High Definition Digital Temperature Map", HD-DTM) were prepared for the current climatological normal year (1971-2000) based on observations at the 56 Korea Meteorological Administration (KMA) stations using a geospatial interpolation scheme for correcting land surface effects (e.g., land use, topography, and elevation). The same procedure was applied to the official temperature projection dataset covering South Korea (under the auspices of the IPCC-SRES A2 and A1B scenarios) for 2071-2100. The dormancy depth model was run with the gridded datasets to estimate the geographical pattern of any changes in the short-term cold hardiness of Campbell Early across South Korea for the current and future normal years (1971-2000 and 2071-2100). We combined this result with the projected mean annual minimum temperature for each period to obtain the potential risk of cold injury. Results showed that both the land areas with the normal cold-hardiness (-150 and below for dormancy depth) and those with the sub-threshold temperature for freezing damage ($-15^{\circ}C$ and below) will decrease in 2071-2100, reducing the freezing risk. Although more land area will encounter less risk in the future, the land area with higher risk (>70%) will expand from 14% at the current normal year to 23 (A1B) ${\sim}5%$ (A2) in the future. Our method can be applied to other deciduous fruit trees for delineating geographical shift of cold-hardiness zone under the projected climate change in the future, thereby providing valuable information for adaptation strategy in fruit industry.

• Korean Journal of Remote Sensing
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• v.23 no.4
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• pp.323-334
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• 2007

We analyzed the ocean environmental data from water sample and automatic measurement instruments with the Incheon-Jeju passenger ship for 18 times during 4 years from 2001 to 2004. The objectives of this study are to monitor the spatial and temporal variations of ocean environmental parameters in coastal waters of the Yellow Sea using water sample analysis, and to compare and analyze the reliability of automatic measurement sensors for chlorophyll and turbidity using in situ measurements. The chlorophyll concentration showed the ranges between 0.1 to $6.0mg/m^3$. High concentrations occurred in the Gyeonggi Bay through all the cruises. The maximum value of chlorophyll concentration was $16.5mg/m^3$ in this area during September 2004. The absorption coefficients of dissolve organic matter at 400 nm showed below $0.5m^{-1}$ except those in August 2001 During 2002-2003, it did not distinctly change the seasonal variations with the ranges 0.1 to $0.4m^{-1}$. In the case of suspended sediment (SS) concentration, most of the area showed below $20g/m^3$ through all seasons except the Gyeonggi Bay and around Mokpo area. In general SS concentration of autumn and winter season was higher than that of summer. The central area of the Yellow Sea appeared to have lower value $10g/m^3$. The YSI fluorometer for chlorophyll concentration had a very low reliability and turbidity sensor had a $R^2$ value of 0.77 through the 4 times measurements comparing with water sampling method. For the automatic measurement using instruments for chlorphlyll and suspended sediment concentration, McVan and Choses sensor was greater than YSI multisensor. The SeaWiFS SS distribution map was well spatially matched with in situ measurement, however, there was a little difference in quantitative concentration.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.21-28
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• 2009

Detailed information on soil characteristics is of great importance for the use and conservation of soil resources that are essential for human welfare and ecosystem sustainability. This paper introduces soil inventory of Korea focusing on national soil database establishment, information systems, use, and future direction for natural resources management. Different scales of soil maps surveyed and soil test data collected by RDA (Rural Development Administration) were computerized to construct digital soil maps and database. Soil chemical properties and heavy metal concentrations in agricultural soils including vulnerable agricultural soils were investigated regularly at fixed sampling points. Internet-based information systems for soil and agro-environmental resources were developed based on 'National Soil Survey Projects' for managing soil resources and for providing soil information to the public, and 'Agroenvironmental Change Monitoring Project' to monitor spatial and temporal changes of agricultural environment will be opened soon. Soils data has a great potential of further application in estimation of soil carbon storage, water capacity, and soil loss. Digital mapping of soil and environment using state-of-the-art and emerging technologies with a pedometrics concept will lead to future direction.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.175-186
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• 2019

Efforts have been made to introduce the climate smart agriculture (CSA) for adaptation to future climate conditions, which would require collection and management of site specific meteorological data. The objectives of this study were to identify requirements for construction of agricultural meteorology information service system (AMISS) using technologies that lead to the fourth industrial revolution, e.g., internet of things (IoT), artificial intelligence, and cloud computing. The IoT sensors that require low cost and low operating current would be useful to organize wireless sensor network (WSN) for collection and analysis of weather measurement data, which would help assessment of productivity for an agricultural ecosystem. It would be recommended to extend the spatial extent of the WSN to a rural community, which would benefit a greater number of farms. It is preferred to create the big data for agricultural meteorology in order to produce and evaluate the site specific data in rural areas. The digital climate map can be improved using artificial intelligence such as deep neural networks. Furthermore, cloud computing and fog computing would help reduce costs and enhance the user experience of the AMISS. In addition, it would be advantageous to combine environmental data and farm management data, e.g., price data for the produce of interest. It would also be needed to develop a mobile application whose user interface could meet the needs of stakeholders. These fourth industrial revolution technologies would facilitate the development of the AMISS and wide application of the CSA.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.5
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• pp.97-111
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• 2021

The purpose of this study was to analyze commemoration characteristics of the United States of America, the Commonwealth, and Germany through representative 14 military cemeteries of World war II in Western Europe. Based on the commemoration characteristics such as spacial characteristic, commemorative elements, and graves and headstone, the commemoration culture among U.S., the Commonwealth. and Germany were studied comparatively. The results are as follows. First, taking geometrical form with mainly square type, rarely circle and spiral patterned, most cemeteries were structured spatial central axis with symmetry, those cemeteries were styled neoclassical, but some of the U.S. cemeteries were modernistic, connecting spaces organically with curved line layout. Second, chapel, the wall of missing, the wall of battle map, and sculpture in the U.S military cemeteries, and 'the cross of sacrifice' and 'the stone of remembrance' as classical monument in the Commonwealth war cemeteries were commonly applied standardized commemorative elements, but commemorative monuments in German military cemeteries were restricted except monumental cross. Third, the symbolic cross of christianism was used all cemeteries to console and cherish the soul of soldiers, specially the Latin crosses in the U.S military cemeteries delivered political message as the american martyr for Western Europe and also the power of the U.S., but the cross in German and the Commonwealth war cemeteries were basically cherish and comfort individual spirit. Fourth, showing the power of victory with national patriotism, the U.S. strongly represented christianism and liberal democracy against communism, the Commonwealth showed imperialistic style, and German military cemeteries were quietly appeared as traditional style forwarding reconciliation and peace. This study suggest the war cemeteries have national identity with typical form and symbolic aesthetics. Further study will be required to materialize sublime commemoration in national cemeteries and to form advanced commemorative culture in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.2
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• pp.63-77
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• 2022

Our aim was to reduce estimation errors of a wind velocity model used as an early warning system for weather risk management in the agricultural sector. The Rural Development Administration (RDA) agricultural weather observation network's wind velocity data and its corresponding estimated data from January to December 2020 were used to calculate linear regression equations (Y = aX + b). In each linear regression, the wind estimation error at 87 points and eight time slots per day (00:00, 03:00, 06:00, 09.00, 12.00, 15.00, 18.00, and 21:00) is the dependent variable (Y), while the estimated wind velocity is the independent variable (X). When the correlation coefficient exceeded 0.5, the regression equation was used as the wind velocity correction equation. In contrast, when the correlation coefficient was less than 0.5, the mean error (ME) at the corresponding points and time slots was substituted as the correction value instead of the regression equation. To enable the use of wind velocity model at a national scale, a distribution map with a grid resolution of 250 m was created. This objective was achieved b y performing a spatial interpolation with an inverse distance weighted (IDW) technique using the regression coefficients (a and b), the correlation coefficient (R), and the ME values for the 87 points and eight time slots. Interpolated grid values for 13 weather observation points in rural areas were then extracted. The wind velocity estimation errors for 13 points from January to December 2019 were corrected and compared with the system's values. After correction, the mean ME of the wind velocities reduced from 0.68 m/s to 0.45 m/s, while the mean RMSE reduced from 1.30 m/s to 1.05 m/s. In conclusion, the system's wind velocities were overestimated across all time slots; however, after the correction model was applied, the overestimation reduced in all time slots, except for 15:00. The ME and RMSE improved b y 33% and 19.2%, respectively. In our system, the warning for wind damage risk to crops is driven by the daily maximum wind speed derived from the daily mean wind speed obtained eight times per day. This approach is expected to reduce false alarms within the context of strong wind risk, by reducing the overestimation of wind velocities.