Recently, urbanization has become a serious issue, as there is imbalance between regions and various environmental problems occur intensively in cities. Therefore, cities all over the world are promoting the Green New Deal and trying to realize carbon neutrality. Accordingly, the European Union is leading the creation of carbon-neutral cities by promoting policies aimed at rapidly realizing carbon neutrality. In Korea, projects such as U-City and Smart City have also been promoted continuously for many years, and recently, the projects Smart Green City and Carbon Neutral Green City have been introduced. Therefore, this study aimed to derive directions and implications for future projects based on policies to address climate change by analyzing the guidelines for the Smart Green City project and the project plans of Gimhae-si and Gangjin-gun, which are the leading projects in the Smart Green City business model and are equipped with an extensive budget.
This study investigated whether an educational program could alter students’ perceptions of the causes of and solutions to climate change. On October 23, 2020, a 3-hour climate change educational program was provided to 400 high school students in Suncheon City, (Jeonnam Province, South Korea). According to the program, climate change represents a social dilemma, or tragedy of the commons; it also asserts that collective action aimed at strengthening government policy is the optimal solution to climate change, and concludes that motivated citizens should convey their opinions directly to the government through political action. After the program, the students made and shared placards calling for policy-based responses to climate change. Questionnaires completed by the students before and after the program revealed that their perceptions of the causes of and solutions to climate change changed significantly. This case study indicates that education programs have the potential to alter students’ perspectives and promote actions aimed at mitigating and adapting to climate change.
This study reassess safety margin of the current Peak Cladding Temperature (PCT) limit of dry storage in terms of hydrogen migration by predicting axial hydrogen diffusion throughout dry storage with respect to wet storage time and average burnup. Applying the hydride nucleation, growth, and dissolution model, an axial finite difference method code for thermal diffusion of hydrogen in zirconium alloy was developed and validated against past experiments. The developed model has been implemented in GIFT – a nuclear fuel analysis code developed by Seoul National University. Various discharge burnups and wet storage time relevant to spent fuel characteristics of Korea were simulated. The result shows that that the amount of hydrogen migrated towards the axial end during dry storage for reference PWR spent fuel is limited to ~50 wppm. This result demonstrates that the current PCT margin is sufficient in terms of hydrogen migration.
The Gwangju Stream is a major tributary of the Yeongsan River. To maintain environmental and ecological functions in the stream, the flow is secured by natural water from the Mudeung Mountain as well as waters discharged from Lake Juam and the Gwangju sewage treatment plants. A substantial amount of water is supplied into the upper reaches of Gwangju Stream from Lake Juam. To examine the ecological effects of the water input from Lake Juam on the Gwangju Stream, a field survey of phytoplankton community species and an evaluation of water properties was conducted at five stations, from station GJ1 before the inflow to station GJ5 in the lower region. Nutrient levels decreased in the vicinity of the Lake Juam inflow, suggesting that this water inflow can contribute to the reduction of eutrophication in the stream. The phytoplankton community was mainly composed of Bacillariophyceae, Chlorophyceae, and Cyanophyceae, and the community structure was similar to that of the other study sites located near the water inflow regions. The inflow of water from Lake Juam can affect water quality and the phytoplankton community over a limited area, reducingeutrophication and increasing water flow in the Gwangju Stream.
It can take hundreds of thousands of years for decreasing radiological effects of high-level radioactive wastes to those of natural background radiation. Therefore, long-term time scale should be considered in order to demonstrate performance and safety of deep geological disposal of the radioactive wastes. The changes of surface environment for these long-term time scale can have influence on safety analysis by changing transport path of radionuclides from the radioactive wastes. Changes in climate is considered as one of main factors causing the long-term changes of the surface environment. The own effects and interactions of climate with other components of the geological disposal system are organized in features, events, and processes (FEPs). In this study, some natural processes occurred by changes of climate were suggested and the connectivity between each process is proposed based on the relation of the FEPs concerned with the changes of climate and surface environment. The processes were classified into global and regional/local scales and was analyzed, respectively. Then, the influences of the processes on shallow groundwater and surface water body environment, which might be transport path of radioactive nuclides in local/site scales, were expected. As the proposed connection demonstrate the order or hierarchical relations of the natural processes, it can shows that some output by a certain process may be input of other process connected the former process in numerical simulations for interpreting the processes. If the connection may be considered to be suitable to represent longterm changes of the surface environment, it can be evaluated that the expected scenarios based on the connection is also proper. In addition, it can be helpful in selecting factors to be studied more detailed in terms of climate change for expecting long-term changes in the surface environment by analysis on the input and output data. The results of this study can be used as basic approaches to represent the long-term changes in the surface environment caused by specific natural processes from changes of climate. It will be also helpful for formulating scenarios related to long-term evolution in the surface environment required for performance and safety assessments of the deep geological disposal.
With the enhancement of the spatial resolution of satellite imagery (1 m or less), the satellite image analysis has been considered as the indispensable means for remote sensing of nuclear proliferation activities in the restricted access areas such as North Korea. Notably, in the case of an open-pit uranium mine, e.g. the Pyongsan uranium mine, the mining activity can be presumed if detecting the location and extent uranium tailing piles near shafts within temporal images. Several studies have researched on the target detection for minerals of interest such as limestone and coal to evaluate the economic activities by utilizing similarity measures, e.g., a spectral angle mapper and a spectral information divergence (SID). Thus, this paper presented a systematic change detection methodology for monitoring the uranium mining activity in the Pyongsan uranium mine with a similarity measure of SID. The proposed methodology using the target detection results consists of the following five steps. The first step is to acquire stereo images of areas of interest for change detection. The second step is to preprocess the stereo images as following measures: (i) the QUick Atmospheric Correction and the image-to-image registration with ENVI and (ii) the Gram-Schmidt pansharpening. The third step is to extract spectral information for minerals of interest, i.e., uranium tailing piles, by sampling pixels within the reference image. It is based on the satellite analysis report for the Pyongsan uranium mine by CSIS, which specified the location of the uranium tailing piles. As the fourth step, the target detection for uranium tailing piles was performed through the similarity measure of SID between the extracted spectral information and the spectral reflectance of the image. In the fifth step, the change detection was processed using the multivariate alteration detection algorithm, which compares the target detection results by canonical correlation analysis. Furthermore, this paper evaluated the performance of the proposed methodology with the change detection accuracy assessment index, i.e., the area under a receiver operating characteristic curve. In conclusion, this paper suggests the systematic change detection methodology utilizing time series analysis of target detection for uranium tailing piles, which can save time and cost for humans to interpret large amounts of satellite information at the restricted access areas. As future works, the feasibility of the proposed methodology would be investigated by analyzing distribution of minerals of interest regarding nuclear proliferation at Yongbyon, which has the historical events of suspicious nuclear activities.
Better understanding the mechanism of black ice occurrence on the road in winter is necessary to reduce the socio-economic damage it causes. In this study, intensive observations of road weather elements and surface information under the influence of synoptic high-pressure patterns (22nd December, 2020 and 29th January, and 25th February, 2021) were carried out using a mobile observation vehicle. We found that temperature and road surface temperature change is significantly influenced by observation time, altitude and structure of the road, surrounding terrain, and traffic volume, especially in tunnels and bridges. In addition, even if the spatial distribution of temperature and road surface temperature for the entire observation route is similar, there is a difference between air and road surface temperatures due to the influence of current weather conditions. The observed road temperature, air temperature and air pressure in Nongong Bridge were significantly different to other fixed road weather observation points.
지구/행성 내부의 다양한 지질학적 과정을 이해하기 위해서는 고온-고압 환경에서 지구 내부 구성 물질의 특성을 이해하는 것이 필수적이다. 이러한 고압환경을 생성하기 위하여 사용되는 멀티 앤빌 프레스 (multi-anvil press)는 주로 상부맨틀조건의 극한 상황을 재현하는데 사용된다. 멀티 엔빌프레스의 지질학적 사 용을 위한 필수 보정 과정 중 하나는 압력을 생성하기 위한 프레스의 유압과 실제로 시료에 가해지는 압력 사이의 관계인 압력-부하 보정(pressure-load calibration)이다. 압력-부하 보정은 일반적으로 고온-고압 조건에 서는 결정질 물질의 상전이를 이용해서 이루어지는데, 고온에서의 경우와 달리 저온(상온)의 경우 상전이 과 정이 상대적으로 비효율적이므로 압력-부하 보정의 다른 방법론이 요구된다. 본 연구에서는 파이로프 조성 (Mg3Al2Si3O12)의 비정질(비정질 파이로프)의 상온에서의 압축(cold compression)에 따라 발생하는 영구적인 고 밀도화 현상(permanent densification)과 그 기원이 되는 알루미늄 배위 환경의 변화를 고해상도의 27Al MAS 및 3QMAS NMR 분광분석을 통해 정량화하고, 이로부터 압력에 따른 알루미늄의 배위수 변화를 이용해 14/ 8 HT 조립세트(assembly set)와 1,100톤 멀티 앤빌 프레스에 대한 상온에서의 압력-부하 보정을 수행하였다. 본 연구는 NMR분광분석을 이용하여 압력보정을 수행한 최초의 연구결과이며, 비정질 파이로프의 압축-감압에 따른 원자 단위에서의 비가역적 구조 변화는 섭입대 환경과 같은 저온 고압 환경에서 비정질 물질이 겪는 변 화와 그에 따른 지질학적 현상의 이해고양에 실마리를 제공한다.
포항 금광동층 함식물화석층 암석의 효과적인 보존을 위하여 구성암석의 특징과 보존처리제 적용을 인공풍화시험을 통해 살펴보았다. 화석지 구성암석은 규조토성 규질이암으로 팽윤성 광물인 스멕타이트를 약간 함유하고 있으며, 엽층리가 발달되어 있다. 화석지 암석은 물과 반응 후 팽윤성 광물의 d001 층간간격이 증가하 였다. 에틸실리케이트 암석강화제를 적용한 후 시편의 경도는 향상되었으나 팽윤성 광물의 층간간격은 감소하 였다. 팽윤저지제를 선처리한 후 강화제를 처리하였을 때 광물 층간간격의 변화는 강화제만을 처리하였을 때와 유사하여 팽윤저지제의 효과는 거의 없었다. 보존약품이 처리된 암석에 수분이 닿았을 경우, 강화제 또는 팽윤 저지제를 선처리한 후 강화제를 처리한 암석 모두 엽층리 간격이 확대되었으나, 습기만 접했을 때는 변화가 적었다. 또한 보존처리 후 노천에 그대로 위치하여 풍화를 받게 되면, 약품이 처리되지 않은 암석에 비해 약간 느리게 발생하기는 하지만, 매우 빠른 시간 내에 엽층리면의 분리와 암석의 분말화가 발생하는 결과를 보였다. 화석지 암석 의 원활한 보존을 위해서는 보존약품의 처리가 필요하나, 강우를 접하고 동결융해과정을 거치면 그 효과는 매우 빠른 시간에 소멸되기 때문에 약품처리에 상관없이 암석에 직접적인 강우의 접촉을 막는 것이 우선적으로 요구된다.
This study was conducted to investigate the effects of adding Tenebrio molitor L Powder to broiler feed on fatty acid profiles in broiler breast meat. In total, 180 broiler chicks (1-day old Arbor Acres) were included. The birds were randomly divided into control and treatment groups, with 3 replicate subgroups each(30 birds per subgroup), and fed a diet for 35 days without (control) or with 1% Tenebrio molitor L powder (treatment). Among individual fatty acids, addition of Tenebrio molitor L. powder resulted in slightly higher C18:1n-9, C20:3n-3 and C20:3n-6 contents, and lower C18:2n-6 content compared withcontrols (p<0.05). No remarkable differences in total SFA and total USFA contents were found between groups. In conclusion, inclusion of Tenebrio molitor L. in broiler diets did not improve overall fatty acid profiles.
This study analyzed how the impacts of major teleconnection patterns on December mean temperature in Korea have been changed during the period before and after the regime shift of 1986 for the last 61 years from 1958 to 2018. During the period before the regime shift, the teleconnection patterns originating from the North Atlantic mainly affected the temperature variability in Korea, but its influence almost disappeared after the regime shift. On the other hand, the Arctic Oscillation (AO) and warm Arctic and cold Eurasia (WACE) patterns played a more important role in the temperature variability in Korea after the regime shift. Regression analysis showed that the AO could explain about 12% of the total temperature variability before the regime shift, but about 22% after the regime shift. WACE pattern also explained about 4% before the regime shift, but after the regime shift, the importance increased by about 4.5 times to 18%. On the other hand, East Atlantic pattern (EA) and North Atlantic Oscillation (NAO), which are east-west teleconnection patterns, explained 27% and 11%, respectively, before the regime shift, but had little influence within 3% after the regime shift. This means that the influence of east-west teleconnection patterns disappeared after the regime shift, and teleconnection patterns by the Arctic Circle became more important.
본 연구는 사립유치원교사의 셀프리더십과 행복감이 이직의도에 미치는 영향에서 근무환경의 매개효과를 규명하기 위해 실시되었다. 강원도와 경기도, 경상도에 소재한 사립유치원에 재직 중인 261명의 교사를 대상으로 인터넷 및 우편, 직접 방문을 통한 설문조사를 진행하였는데, 셀프리더십 질문지, 행복감 질문지, 이직의도 질문지, 근무환경 질문지를 사용하였다. 수집된 자료는 SPSS 25.0과 AMOS 25.0 통계프로그램을 사용하여 분석하였으며, 결과처리를 위해 빈도와 백분율 산출, 신뢰도 검증, 적률상관분석, 경로분석과 Sobel test를 실시하였다. 연구결과 첫째, 사립유 치원교사의 셀프리더십과 이직의도의 관계에서 근무환경은 완전매개역할을 하는 것으로 나타났다. 둘째, 사립유치원교사의 행복감과 이직의도의 관계에서 근무환경은 완전매개역할을 하는 것으로 나타났다. 본 연구결과를 통해 사립유치원교사의 이직의도를 낮출 수 있는 다양한 방안과 보다 질 높은 근무환경을 모색하기 위한 기초자료를 제시하였다는데 연구의 의의가 있다.
Climate change is considered as a major threat for agricultural production in Vietnam, particularly for coffee production, one of the most important agricultural sectors of the country. To effectively cope with the negative impacts of climate change on coffee production, the ways of understanding and also adequate responses by farmers on the climate change are very important. This paper aims to provide empirical insights into the farmers’ perception of climate change and their adaptation practices to its impacts on coffee production. The results from the questionnaire survey of 151 smallholder coffee farmers in Dak Nong province reveal the fact that the farmers understood the progress and impact of climate change through their observation into their surrounding areas. Coffee growers’ observation about the climate variability is remarkably consistent with the statistical data from the meteorological authority. However, this research revealed that their capacity to cope with climate change was relatively limited, mostly based on their own resources. This research suggests that more studies are required to examine the application of environmentally sustainable approaches to cope with climate changes.
This study was undertaken to find out national level changes in area, production and yield of two major staple crops wheat and potato in Bangladesh. The time series of secondary data was collected from yearbook of agricultural statistics under Bangladesh Bureau of Statistics (BBS) and used for the statistical analysis during the thirty-year period of 1989/90-2018/19. Moreover, selected data were divided into two groups and regarded as segment (1989/90-2003/04, 2005/06-2018/19) to examine the significant level in each crop. The results of different statistical techniques showed that wheat cultivated area and production were satisfactory level but yield was not too much standard in context of country demand. In the case of potato, yield as well as cultivated area and production were crossed the significant level and fulfilled the demand of population. In recent few years, the ratio of potato production rapidly increased, compared with the cultivation area. Based on segment (period) analysis, at the first half wheat production was always below, compared with the area but second half nine years saw slightly improved. On the other hand, in both segment potato growth rate in area, production and yield were increased throughout the study period. The highest instability was also shown in area, production and yield of potato during whole as well as segmented period. There was always a positive relationship between country’s demand and supply. Both wheat and potato are considered as staple crops and based on the productive capability over cultivated area, potato showed the higher productivity for the country of Bangladesh. In consequences, potato consuming demand also rapidly increased all over the country, compared with past respectively.
This paper has presented not only the spatial coverage change of climate extreme events in summer and winter seasons during the period of 2000-2017, but also their future projections in 2021-2100, South Korea through analysis of a Combined Climate Extreme Index (CCEI). The CCEI quantifies the spatial coverage of climate extreme events based on a set of five indicators. MK (Modified Korean)-PRISM (Parameter-elevation Regression on Independent Slopes Model)v1.2 (1×1km) and RCP scenario data (1×1km) were applied to CCEI. Results indicated that in average, 21.7% of the areas in the summer and 23.6% in the winter experienced climate extremes from 2000 to 2017 regardless of types of climate extreme events in South Korea. The summer of 2003 and 2009 was relatively cool and humid, while the summer of 2014 and 2015 was cool and dry and the summer of 2016 was warm and dry. The extreme events with much above normal maximum and minimum temperature during the study period were detected but not much below normal maximum and minimum temperature after 2015. For RCP2.6 and RCP8.5 scenarios, there were statistically significant trends with spatial coverage expansion of climate extreme events in the future. It might be concluded that climate extreme events in the summer and winter seasons were affected simultaneously by two or more indicators than a single indicator in South Korea.