• Korean Journal of Ecology and Environment
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• v.55 no.2
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• pp.156-166
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• 2022

Understanding the characteristics of reservoir water quality is fundamental in reservoir ecosystem management. The water quality of reservoirs is affected by various factors including hydro-morphology of reservoirs, land use/cover, and human activities in their catchments. In this study, we classified 83 major reservoirs in South Korea based on nine physicochemical factors (pH, dissolved oxygen, chemical oxygen demand, total suspended solid, total nitrogen, total phosphorus, total organic carbon, electric conductivity, and chlorophyll-a) measured for five years (2015~2019). Study reservoirs were classified into five main clusters through hierarchical cluster analysis. Each cluster reflected differences in the water quality of reservoirs as well as hydromorphological variables such as elevation, catchment area, full water level, and full storage. In particular, water quality condition was low at a low elevation with large reservoirs representing cluster I. In the comparison of eutrophication status in major reservoirs in South Korea using the Korean trophic state index, in some reservoirs including cluster IV composed of lagoons, the eutrophication was improved compared to 2004~2008. However, eutrophication status has been more impaired in most agricultural reservoirs in clusters I, III, and V than past. Therefore, more attention is needed to improve the water quality of these reservoirs.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6D
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• pp.761-770
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• 2009

The energy efficiency and environment-friendly aspect of the railway system would be superior to other on-land ransportation systems. In a preliminary feasibility study stage and selection of optimal railway route, the energy efficiency and problems related to environment are usually considered. For the selection of optimal railway route, geographical features and facility of management are generally considered. Environment effect factors for the selection of environment-friendly railway router are focused and studied in this paper. In this study, various analysis of opinion of specialists (railway, environment, transport, urban planning, survey) and the guideline for construction of environment-friendly railway were accomplished. From these results of various analysis, 7 major categories (topography/geology, flora and fauna, Nature Property, air quality, water quality, noise/vibration, visual impact/cultural assets) were extracted. To select environment friendly railway route, many alternatives should be compared optimal route must be selected by a comprehensive assessment considering these 7 categories. To solve this problem, the selected method was AHP which simplifies the complex problems utilizing hierarchy, quantifying qualitative problems through 1:1 comparison, and extracting objective conclusions by maintaining consistency. As a result, a GUIbased program was developed which provides basic values of weighted parameters of each category defined by specialists, and a quantification of detailed assessment guidelines to ensures consistency.

• The Korean Journal of Archival Studies
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• no.78
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• pp.5-42
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• 2023

Since presidential overseas trips are carried out as the head of state representing the Republic of Korea, the resulting records of such trips have high academic and historical significance and value both in contemporary times and for future generations. This study analyzes the status of production and service of overseas trip records, focusing on whether the records of the president's overseas trips are being produced properly and provided sufficiently to the public, and examines development plans for improvement. Currently, as a result of examining a total of 282 overseas trips provided by the Presidential Archives website, it is difficult for users to understand which records are being produced for even the basic records regarding the trips are not posted. In addition, the website is provider-centered, making users feel alienated rather than being considered in terms of search and provided records. In this study, for the production of high-quality overseas travel records, the "Presidential Overseas Trip Records Production Guidelines" established during the 'Participatory Government' will be supplemented, improved and applied. This archive policy will not be subject to any external variables, including changes in the government, and is suggested that it be consistent and unaffected. In addition, in order to improve the service provided, the following is proposed: first, provision of 'comprehensive information' that allows users to understand the overall context of the trip; second, use of the "file-record" layer and hyperlink function; third, a system that allows the stages of production and service of overseas trip records to be interconnected. In order to carry out these tasks, it would be essential to establish and operate an organization dedicated to records, such as the Secretariat of Archives and Records Management during the 'Participatory Government' period.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.430-436
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• 2023

Study on Changes in Vessel Traffic Services Due to Introduction of Maritime Autonomous Surface ShipsThe development of technologies related to Maritime Autonomous Surface Ships (MASS) has been actively progressing since the mid-2010s, focusing on themes such as collision avoidance, route planning, digital twin, and communication technologies. On the other hand, research on land-based infrastructure connected with MASS, such as logistics systems, port facilities, and vessel traffic services, has relatively received less attention. This study analyzed impact of emergence of MASS on existing vessel traffic service operations and proposed changes in control operations to prepare for its impact. To do this, current vessel traffic service operations were analyzed and elements of MASS technology that could affect vessel traffic control were identified. A survey was conducted among vessel traffic controllers to identify items related to the control of MASS. Results analyzed using the AHP method showed that preparation for emergency response and communication methods with MASS were the most important. Based on this, we were able to derive detailed plans for basic MASS control procedures and emergency response procedures based on data communication within maritime traffic control areas. MASS control procedures proposed in this study are expected to be used as a solution to resolve issues related to traffic safety of MASS in coastal areas.

• The Transactions of the Korea Information Processing Society
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• v.13 no.4
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• pp.199-207
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• 2024

Local reservoirs are crucial sources for agricultural water supply, necessitating stable water level management to prepare for extreme climate conditions such as droughts. Water level prediction is significantly influenced by local climate characteristics, such as localized rainfall, as well as seasonal factors including cropping times, making it essential to understand the correlation between input and output data as much as selecting an appropriate prediction model. In this study, extensive multivariate data from over 400 reservoirs in Jeollabuk-do from 1991 to 2022 was utilized to train and validate a water level prediction model that comprehensively reflects the complex hydrological and climatological environmental factors of each reservoir, and to analyze the impact of each input feature on the prediction performance of water levels. Instead of focusing on improvements in water level performance through neural network structures, the study adopts a basic Feedforward Neural Network composed of fully connected layers, batch normalization, dropout, and activation functions, focusing on the correlation between multivariate input data and prediction performance. Additionally, most existing studies only present short-term prediction performance on a daily basis, which is not suitable for practical environments that require medium to long-term predictions, such as 10 days or a month. Therefore, this study measured the water level prediction performance up to one month ahead through a recursive method that uses daily prediction values as the next input. The experiment identified performance changes according to the prediction period and analyzed the impact of each input feature on the overall performance based on an Ablation study.

• Journal of Korean Elementary Science Education
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• v.43 no.2
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• pp.219-232
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• 2024

This study aims to determine the perspectives of pre-service elementary school teachers on the science curriculum in the fourth industrial revolution era. In this study, 128 pre-service elementary school teachers were asked to express their perspectives on the Saber-toothed Tiger Curriculum through photovoice activities. The resulting images were classified into three types: conservative, progressive, and radical perspectives. The number of both conservative and progressive perspectives was similar and high, whereas the number of radical perspectives was l ow. Those who had conservative perspectives on the Saber-toothed Tiger curriculum regarded "Inquiry" as the basis of the science curriculum, which should be maintained regardless of the time period and environment. Similarly, older teachers believed that this curriculum was based on eternal truth, which should be protected. Those who showed progressive perspectives on the Saber-toothed Tiger curriculum regarded a progressive person as someone succeeding to the blood of "New fist," and they showed positive attitudes toward AI-based education such as coding and meta-verse, regarding these practices as part of the teaching and learning method that could replace the existing inquiry-based education. Those who showed radical perspectives on the Saber-toothed Tiger Curriculum assumed critical attitudes toward the rapidly changing political circumstances of science education and criticized conflicts between different social classes formed through progressive curriculum. Based on these results, this study found that pre-service elementary school teachers needed to consider the science curriculum from several different perspectives rather than just one.

• Journal of The Korean Association For Science Education
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• v.26 no.6
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• pp.675-690
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• 2006

This study investigated students' views in relation to a career in science as a first step towards developing science career education programs and materials. The instrument was developed through preliminary surveys. The questionnaire was sent to, administered and returned by 3608 students including 1036 primary, 1137 middle, and 1435 high school students, who were selected through stratified cluster sampling from all over the country. The results were analyzed using statistical package program. The students' image view of science, preference for science and science learning, perception of science achievement, career hope for oneself, degree of hope in getting science-related job, perception about science-related career, important factors of science career choice, and their hope for science/non-science career and the reason for their choice in the past and present were investigated. The results show that "science as an experimentation activity" was the most frequent image view of science. The preference for science and science learning was more positive than the perception of science achievement. The percentage of total students who want to have science career was 21%, and this percentage of middle school students was especially low. The most frequent answers for advantages of science career were 'useful for national development', 'possible to get new knowledge', and those for disadvantages were 'dangerous', and 'too much to study'. The most frequent reason for students' choice of a science career was 'interest in science and science learning'. Judging from these results, the basic direction for science career education should be in raising the students' preference for and interest in science learning. The positive awareness for a career in science and vision for a science job in the future should be given through a science career education and science career education proper to the students' developmental stage and characteristics is more important.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.101-116
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• 2018

Sustainability science is an emerging transdisciplinary research which necessitates not only the communication and collaboration of scientists, practitioners and stakeholders from different disciplines and interests, but also the paradigm shift from deterministic and reductionist approaches to the old basic. Ecological-societal systems (ESS) are co-evolving complex systems having many interacting parts (or agents) whose random interactions at local scale give rise to spontaneous emerging order at global scale (i.e., self-organization). Here, the flows of energy, matter and information between the systems and their surroundings play a key role. We introduce a conceptual framework for such continually morphing dynamical systems, i.e. self-organizing hierarchical open systems (SOHOs). To understand the structure and functionality of SOHOs, we revisit the two fundamental laws of physics. Re-interpretation of these principles helps understand the destiny and better path toward sustainability, and how to reconcile ecosystem integrity with societal vision and value. We then integrate the so-called visioneering (V) framework with that of SOHOs as feedback/feedforward loops so that 'a nudged self-organization' may guide systems' agents to work together toward sustainable ESS. Finally, example is given with newly endorsed Sustainable Development Goals (SDG) Lab (i.e., 'Rural systems visioneering') by Future Earth, which is now underway in rural villages in Tanzania.

• Journal of Agricultural Extension & Community Development
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• v.6 no.2
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• pp.75-84
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• 1999

Minnesota state law requires County Extension Committees (CECs). The County Board of Commissioners appoints committee members. Extension Educators are responsible for using CECs to assure the value of Extension work in the County. This paper will explore underlying values, principles and practices that can effect the utilization of CECs in ways that benefit the work of Extension and make the process a good experience for CEC members and Extension Educator. The paper is based primarily on readings in the Journal of Extension, interviews with two Extension Educator, and information provided by the University of Minnesota Extension Service for CEC members.

• Journal of the Korean Geographical Society
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• v.29 no.1
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• pp.65-83
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• 1994

Sevaral problems of administrative area sysem in Korea have been brought up for a long time. Because its frame has remained since Chosun and Japanese colonial period in spite of changing local administrative environment in accordance with rapid industrialization and urbanization. Recent reform of city (Shi)- county (Gun) integration is derived from this argument. But problems which permeate deeply overall system cannot be solved by partial reorganization of Shi-Gun. They may be rationalized only through the reform of the whole system. The aims of this study are to analyze problems of administrative area system entirelr and to discuss the direction of its reform from that point of view. Major problems of administrative area system are summed up into the followings. Firstly, it is found that administrative hierarchies are too many levels. Contemporary administrative hierarchical structure is 4 levels: regional autonomous government (Tukpyolshi, Jik'halshi, Do), local autonomous government (Shi, Gun), two leveis of auxiliary administrative area (Up, Myun and Ri). These hierarchies were established in late period of Chosun which transportation was undeveloped and residential activity space was confined. But today developing transportion and expanding sphere of life don't need administrative hierarchical structurl with many levels. Besides developing administrative technology reduces administrative space by degrees. Many levels of contemporary administrative hierarchical structure are main factor of administrative inefficency, discording with settlement system. Second problem is that Tukpyolshi and Jik'halshi - cities under direct control of the central government as metropolitan area - underbounded cities. Underbounded city discomforts residential life and increases external elects of local pulic services. Especially this problem is Seoul, Pusan and Daegu. Third problem is that Do-areas are mostly two larger in integrating into single sphere of life. In fact each of them consistes of two or three sphere of life. Fourth Problem is metropolitan government system that central city is seperated from complementary area, i.e. Do. It brings about weakening the economic force of Do. Fifth problem is that several cities divided single sphere of life. It is main factor of finantial inefficency and facing difficult regional administration. Finally necessity of rural parish (Myun.) is diminished gradually with higher order center oriented activty of rural residents. First of all administrative area system should corresponds with substantial sphere of life in order to solve these problems. Followings are some key directions this study proposes on the reform of administrative area system from that standpoint. 1. Principles of reorgnization -- integration of central dty with complementary area. -- correspondence of administrative hierarchical structure with settlement system. -- correspondence of boundary of administrative area with sphere of life. 2. Reform strategy -- Jik'halshi is integrated with Do and is under the contol of Do. -- Small Seoul shi (city) which have special functions as captal is demarcated in Seoul tukpyolshi and 22 autonomous distrcts of Seoul tukpyolshi is integrated into 3-4 cities. -- Neighboring cities (Shies) in single sphere of life are intrgrated into single city (Shj). -- Myun and Ri are abolished in rural region and new unit of local administrative area on the basis of lowest order sphere of life into which 3-4 Ries are integrated replaces them.