• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3672-3681
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• 2022

This study investigates the environmental footprint impacts of nuclear energy consumption in the presence of environmental technology and globalization of the ten largest ecological footprint countries from 1990 up to 2017. By considering a set of methods that can help solve the issue of cross-sectional dependence, we employ the Lagrange multiplier bootstrap cointegration method, Driscoll-Kraay standard errors for long-run estimation and feasible generalized least squares (FGLS) and panel-corrected standard errors (PCSE) for robustness. The finding revealed significant negative effects of nuclear energy consumption, environmental-related technology, population density and significant positive effects of globalization and economic growth on ecological footprint. These results are also robust by assessing the long-run impacts of predictors on carbon footprint and CO₂ emissions as alternate ecological measures. These conclusions provide the profound significance of nuclear energy consumption for environmentally sustainable development in the top ten ecological footprint countries and serve as an important reference for ecological security for other countries globally.

• KIEAE Journal
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• 제14권6호
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• pp.87-92
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• 2014

The objectives of this study are to investigate input variables of photovoltaic generation programs and to compare their prediction to actual generation of photovoltaic system in the C city hall and the C city sewage treatment plant. We investigated the actual amount of generation, the forecast amount of generation, the amount of solar radiation data, and calculated the relative errors. We simulated the photovoltaic system of C city hall and the C city sewage treatment plant located in Chungju using existing programs, such as SAM, RETSCREEN, HOMER, PV SYST, Solar Pro. The result of this study are as follows : Through examining the relative errors of monthly predicted and actual generation data, monthly generation data showed big errors in winter season?. Except winter season, actual amount of generation and the predicted amount of generation showed no large errors.

• 한국지역지리학회지
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• 제14권3호
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• pp.189-198
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• 2008

본 연구의 목적은 2011년 세계육상선수권대회 개최지로 선정된 대구시의 도시 이미지 제고에 필요한 대구의 문화생태환경 복원과 활용을 위한 기초자료를 제공하는 데 있다. 본 연구를 통해 얻은 주된 결과는 다음과 같다. 첫째, 잘못 알려져 있는 대표적인 자연경관은 신천과 입암으로 이에 대한 수정이 시급히 요구되며, 이 외에도 지명의 오기에 대한 수정이 필요하다. 둘째, 고문헌에 전해지는 대구의 두 바위 중 하나인 입암은 이미 사라진 상태이지만, 화암은 최근에 그것의 실체가 밝혀진 만큼 이에 대한 충분한 보존방안이 마련되어야 할 것이다. 셋째, 사라질 위기에 처한 주요 자연경관의 보존을 위해 이들을 대구 문화생태관광 자원으로 활용하는 방안을 제시한다. 넷째, 연구자는 본 연구에서 중요하게 다루고 있는 지형경관 중에서도 문화 또는 역사와 관련된 지형경관을 특별히 '문화지형(Cultural landform)'으로 부를 것을 제안한다.

• 한국환경복원기술학회지
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• 제18권1호
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• pp.127-133
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• 2015

Interests in ecosystem services have increased and a number of attempts to perform a quantitative valuation on them have been undertaken. To classify the ecosystem types landcover classification maps are generally used. However, some forest types on landcover classification maps have a number of errors. The purpose of this study is to verify the forest types on the landcover map by using a variety of field survey data and to suggest an improved method for forest type classifications. Forest types are compared by overlaying the landcover classification map with the 4th forest type map, and then they are verified by using National Forest Inventory, 3rd National Ecosystem Survey and field survey data. Misclassifications of forest types are found on the forest on the forest type map and farm and other grassland on the landcover map. Some errors of forest types occur at Daegu, Busan and Ulsan metropolitan cities and Gangwon province. The results of accuracy in comprehensive classification show that deciduous forest is 76.1%; coniferous forest is 54.0%; and mixed forest is 22.2%. In order to increase the classification accuracy of forest types a number of remote sensing images during various time periods should be used and the survey period of NFI and the National Forest Inventory and National Ecosystem Survey should be consistent. Also, examining areas with wide forest patch should be prioritized during the field survey in order to decrease any errors.

• KIEAE Journal
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• 제16권1호
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• pp.89-94
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• 2016

This study is part of three-dimensional(3D) heat transfer analysis program developmental process. The program is being developed without it's own built in 3D-modeller. So 3D-model must be created from another 3D-modeller such as generic CAD programs and imported to the developed program. After that, according to the 3D-geometric data form imported model, 3D-mesh created for numerical calculation. But the 3D-model created from another 3D-modeller is likely to have errors in it's geometric data such as mismatch of position between vertexes or surfaces. these errors make it difficult to create 3D-mesh for calculation. These errors are must be detected and cured in the pre-process before creating 3D-mesh. So, in this study four kinds of filters and functions are developed and tested. Firstly, 'vertex error filter' is developed for detecting and curing for position data errors between vertexes. Secondly, 'normal vector error filter' is developed for errors of surface's normal vector in 3D-model. Thirdly, 'intersection filter' is developed for extracting and creating intersection surface between adjacent objects. fourthly, 'polygon-line filter' is developed for indicating outlines of object in 3D-model. the developed filters and functions were tested on several shapes of 3D-models. and confirmed applicability. these developed filters and functions will be applied to the developed program and tested and modified continuously for less errors and more accuracy.

• 한국환경복원기술학회지
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• 제20권1호
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• pp.25-34
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• 2017

The objective of this study is to seek for improvement measures to make the Ecosystem and Nature Map by analyzing causes for grade changes and distributional characteristics of areas with public objections to the Ecosystem and Nature Map notified by e-official gazette from 2014 to June 2016. The receipt of public appeals has been recently increased from average 23 cases a year(2007-2013) to average 33 cases a year(2014-June 2016) while there were 42 areas with public appeals for less than the minimum area($62,500m^2$) for the evaluation of grade of the Ecosystem and Nature Map. Most of the public appeals focused on the 1st grade zone of the Ecosystem and Nature Map. Before grade changes by public appeals, the 1st grade zone of the Ecosystem and Nature Map were 76.0% of the whole areas with public appeals. However, after grade changes by public appeals, it was rapidly decreased to 25.2%, which means that a lot of the 1st grade zone with public appeals were lowered. In the results of analyzing the distributional characteristics of areas with public appeals, they were mostly distributed in lowland(less than 250m altitude), section with $10{\sim}20^{\circ}$ slope, and areas close to or within 100m from built-up area. Regarding areas with public appeals, the biggest time difference between the period of the existing research by National Ecosystem Survey and the period of notice after completing the treatment of public appeals was 18 years while areas showing 6-15 years of time difference were about 70%. Thus, there were huge differences in time of research and notice. Also, the biggest causes for grade changes were boundary errors caused by small-scale survey, and then followed by changes in evaluation of endangered species and occurrence of built-up area and damaged land. Analyzing areas with public appeals in each evaluation item of the Ecosystem and Nature Map, vegetation part was 73.0%, and endangered species area was 23.1% while topography and wetland was less.

• Asian-Australasian Journal of Animal Sciences
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• 제15권5호
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• pp.643-649
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• 2002

Availability of feeds and fodder and amount of their intake by large ruminants in eight different agro-ecological zones (AEZ) of Bangladesh were recorded over a year. Roughages such as straw, naturally grown green grass, water hyacinth, tree leaves, legumes and sugarcane tops were the major feedstuffs fed to the large ruminants. Amount of intake of these ingredients differed (p<0.01) across AEZ studied, but did not differ across seasons or farmers' categories (p>0.05) except for green grasses (p<0.01). Byproduct concentrates offered to animals in the studied areas were rice bran, wheat bran and different oil cakes. The amount of intake of concentrates by the animals also differed (p<0.01) across AEZs, but did not differ across seasons or farmers' categories (p>0.05), except for rice bran and wheat bran which differed between season and farm category, and season respectively (p<0.01). The large standard errors of mean indicate that there are wide variations in intake of roughages and concentrates across AEZ's, seasons and farmers' categories and even across days. This further indicates that the feeding practices of large ruminants are largely heterogeneous. In addition to feeding roughage and concentrates, the animals were allowed to graze for six hours a day. Grazing hours also differed (p<0.01) across AEZ, but not by farmers' categories or seasons.

• 한국환경과학회지
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• 제27권11호
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• pp.1155-1167
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• 2018

We developed a small sensor observation system (SSOS) at a relatively low cost to observe the atmospheric boundary layer. The accuracy of the SSOS sensor was compared with that of the automatic weather system (AWS) and meteorological tower at the Korea Meteorological Administration (KMA). Comparisons between SSOS sensors and KMA sensors were carried out by dividing into ground and lower atmosphere. As a result of comparing the raw data of the SSOS sensor with the raw data of AWS and the observation tower by applying the root-mean-square-error to the error, the corresponding values were within the error tolerance range (KMA meteorological reference point: humidity ${\pm}5%$, atmospheric pressure ${\pm}0.5hPa$, temperature ${\pm}0.5^{\circ}C$. In the case of humidity, even if the altitude changed, it tends to be underestimated. In the case of temperature, when the altitude rose to 40 m above the ground, the value changed from underestimation to overestimation. However, it can be confirmed that the errors are within the KMA's permissible range after correction.

• Journal of Forest and Environmental Science
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• 제39권3호
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• pp.119-127
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• 2023

In this study, quantitative models were applied to case parks to estimate the carbon reduction by trees, which was compared and analyzed at the tree and park levels. At the tree level, quantitative models of carbon storage and uptake differed by up to 7.9 times, even for the same species and size. At the park level, the carbon reduction from quantitative models varied by up to 3.7 times for the same park. In other words, carbon reduction by quantitative models exhibited considerable variation at the tree and park levels. These differences are likely due to the use of different growth environment coefficients and annual diameter at breast height growth rates and the overestimation of carbon reduction due to the substitution of the same genus and group model for each tree species. Extending the annual carbon uptake per unit area of the case park to the total park area of Chuncheon a carbon uptake ranging from a minimum of 370.4 t/yr and a maximum of 929.3 t/yr, and the difference can reach up to 558.9 t/yr. This is equivalent to the carbon emissions from the annual household electricity consumption of approximately 2,430 people. These results suggest that the indiscriminate application of quantitative models to estimate carbon reduction in urban trees can lead to significant errors and deviations in estimating carbon storage and uptake in urban greenspaces. The findings of this study can serve as a basis for estimating carbon reduction in urban greening research, projects, and policies.

• KIEAE Journal
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• 제6권4호
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• pp.25-32
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• 2006

Mock-up model can be applied to measure accurate performance data but difficult to apply the variables in experiment. There can be a slight experiment errors in Scale model, but various parameters can be applied for a objective experiment. This paper aims to compare the daylighting performance in 1, 1/5, 1/10 scale model of offices and analyze the experiment errors to certificate the influence of model experiment. To analyse daylighting performance, a comparison of a Mock-up model, sized $12.0m(w){\times}7.2m(l){\times}3.7m(h)$, designed for experimentation of daylighting systems and its 1:5, 1:10 scale model. It has an identical configuration of reference room and the test room. For the test room, the lightshelf system was designed as Micro-4 reflective material. To assess work plane illuminance and light factor, photometric sensors of each room were installed at work-plane(6 points) and exterior horizontal illuminance (1 point). And luminance of window, rare of the room was measured under clear sky. It is to be monitored by Agilent data logger, photometric sensor Li-cor and the Radiant Imaging ProMetric 1400. Comparisons with a light factor, increase-decrease ratio and luminance are discussed.