• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1659-1663
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• 1991

A new control design methodology is presented here which is based on a nonlinear time-series reference model. It is indicated by highly nonlinear simulations that such designs successfully stabilize troublesome aircraft maneuvers undergoing large changes in angle of attack as well as large electric power transients due to line faults. In both applications, the nonlinear controller was significantly better than the corresponding linear adaptive controller. For the electric power network, a flexible a.c. transmission system (FACTS) with series capacitor power feedback control is studied. A bilinear auto-regressive moving average (BARMA) reference model is identified from system data and the feedback control manipulated according to a desired reference state. The control is optimized according to a predictive one-step quadratic performance index (J). A similar algorithm is derived for control of rapid changes in aircraft angle of attack over a normally unstable flight regime. In the latter case, however, a generalization of a bilinear time-series model reference includes quadratic and cubic terms in angle of attack. These applications are typical of the numerous plants for which nonlinear adaptive control has the potential to provide significant performance improvements. For aircraft control, significant maneuverability gains can provide safer transportation under large windshear disturbances as well as tactical advantages. For FACTS, there is the potential for significant increase in admissible electric power transmission over available transmission lines along with energy conservation. Electric power systems are inherently nonlinear for significant transient variations from synchronism such as may result for large fault disturbances. In such cases, traditional linear controllers may not stabilize the swing (in rotor angle) without inefficient energy wasting strategies to shed loads, etc. Fortunately, the advent of power electronics (e.g., high-speed thyristors) admits the possibility of adaptive control by means of FACTS. Line admittance manipulation seems to be an effective means to achieve stabilization and high efficiency for such FACTS. This results in parametric (or multiplicative) control of a highly nonlinear plant.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.149-152
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• 2005

A new methodology to detect forest fire burnt scars at near real time using MODIS (Moderate-resolution Imaging Spectroradiometer) data is presented here with a goal of introducing a new and improved capability to detect forest fire burnt scars in Thailand. This new technology is expected to increase the efficiency and effectiveness of the forest fire tackling resources distribution and management of the country. Using MODIS data in burnt scars detection has two major advantages - high availability of data and high resolution per performance ratio. Results prove the near real time algorithm suitable and working well in order to monitor the forest fire dynamic movement. The algorithm is based on the threshold separated linear equation of burnt and un-burnt. A ground truth experiment confirms the burnt and un-burnt? areas characteristics (temperature and NDVI). A threshold line on a scatter plot of Band I and Band 2 is determined to separate the burnt from un-burnt pixels. The different threshold values of NDVI and temperature use to identify pixels' anomaly, abnormal low NDVI and high temperature. The overlay (superimpose) method is used to verify burnt pixels. Since forest fire is a dynamic phenomenon, MODIS burnt scars information is suiting well to fill in the missing temporal information of LANDSAT for the forest fire control managing strategy in Thailand. This study was conducted in the Huai-Kha-Kaeng (HKK) Wildlife Sanctuary, Thailand

• 한국실내디자인학회논문집
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• 제21권2호
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• pp.3-13
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• 2012

With the emergence of the smart era, interest in future society and new dwelling spaces is growing. This research analyzes the planning items applied to future house pavilions in Korea to examine which functions will be more emphasized and considered importantly in the dwelling spaces. This research paper aims to identify those dwelling functions that will occupy greater importance from the users' point of view. As for the research methodology, it comprised a literature review and an analysis of case studies. The results of this research were as follows; 1) It was arranged that the dwelling functions were safety, amenity, convenience, independence, economics, society, relaxation, aesthetic appearance. 2) For future dwelling environments, environment-friendly technology for conservation of energy was important in addition to intellectual cutting edge technologies, 3) Safety was most basic among all dwelling functions, 4) Planning items related to amenity and economics were found to be most common, indicating that they were important functions in future dwelling environments, 5) With regard to convenience, planning items related to increasing efficiency of household chores through the application of ubiquitous technology were found to be most common, 6) There was no indication of planning items related to independence and society, 7) Cutting edge technology and emotional technology appear to be integrated in planning items related to relaxation and aesthetic appearance, and 8) Each future dwelling pavilion suggested that over 80% of the planning items were related to amenity, convenience, and economics. We expect that the results from our research will be useful in creating a life-centered design of future dwelling spaces that account for dwelling functions.

• Smart Structures and Systems
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• 제4권2호
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• pp.209-220
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• 2008

A methodology for the seismic vulnerability assessment of historical monuments is presented in this paper. The ongoing work has been conducted in Tunisia within the framework of the FP6 European Union project (WIND-CHIME) on the use of appropriate modern seismic protective systems in the conservation of Mediterranean historical buildings in earthquake-prone areas. The case study is the five-century-old Zaouia of Sidi Kassem Djilizi, located downtown Tunis, the capital of Tunisia. Ambient vibration tests were conducted on the case study using a number of force-balance accelerometers placed at selected locations. The Enhanced Frequency Domain Decomposition (EFDD) technique was applied to extract the dynamic characteristics of the monument. A 3-D finite element model was developed and updated to obtain reasonable correlation between experimental and numerical modal properties. The set of parameters selected for the updating consists of the modulus of elasticity in each wall element of the finite element model. Seismic vulnerability assessment of the case study was carried out via three-dimensional time-history dynamic analyses of the structure. Dynamic stresses were computed and damage was evaluated according to a masonry specific plane failure criterion. Statistics on the occurrence, location and type of failure provide a general view for the probable damage level and mode. Results indicate a high vulnerability that confirms the need for intervention and retrofit.

• 물과 미래
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• 제10권1호
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• pp.53-70
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• 1977

The analysis performed here is aimed to increase the familiarity of hydrologic process especially for the small basins which are densely gaged. Kyung An and Mu Shim river basins are selected as a representative basin according to the criteria which UNESCO has established back in 1964 and being operated under the auspice of Ministry of Construction. The data exerted from these basins is utilized for the determination of characteristics of procipitation and runoff phenomena for the small basin, which is considered as a typical Korean samall watershed. The study found that the areal distribution of preciptation did not show any significant deviation from the point rainfall. Since the area studied is less than 20 km#, the pointrainfall may be safely utilized as a representative value for the area. Also the effect of elevation on the precipitation has a minor significance in the small area where the elevation difference is less than 200m. The methodology developed by Soil Conservation Service for determination of runoff value from precipitation is applied to find the suitability of the method to Korean river basin. The soil cover complex number or runoff curve number was determined by comsidering the type of soil, soil cover, land use and other factors such as antecedent moisture content. The average values of CN for Kyung An and Mushim river basins were found to be 63.9 and 63.1 respectively under AMC II, however, values obtained from soil cover complex were less than those from total precipitation and effective precipitation about 10-30%. It may be worth to note that an attention has to be paid in application of SCS method to Korean river basin by adjusting 10-30% increase to the value obtained from soil cover complex. Finally, the design flood hydrograph was consturcted by employing unit hydrograph technique to the dimensionless mass curve. Also a stepwise multiple regression was performed to find the relationship between runoff and API, evapotranspiration rate, 5 days antecedentprecipitation and daily temperature.

• 건축역사연구
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• 제20권1호
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• pp.61-75
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• 2011

This study aims to investigate the changing aspects about research methodology of stone pagoda from the period of Japanese colonial to now. There were the differences in purpose, method and analysis of the research according to each period. In Japanese colonial period, the purpose of research was to make lists of almost stone pagodas in Korea. Following this, Japanese researchers conducted detailed research for academic purpose. They took measurements of stone pagodas and made drawings. After liberation the research was focused on the relics contained in pagodas. They proceeded to investigate the inner relics in order to attract the attention of the people. In the late 1900's, the repair works of cultural heritages were increased. Many reports of the repair works were released and sent to administration offices. The reports contained the change aspects of situation between before work and after with drawings or simple investigation documents. In the 1990's, the restoration works for important stone pagodas were started by the National Research Institute of Cultural Heritage. Since then, researches from various way - architectural and conservational researches about historical interpretation, shape, structure, proportion, technique, etc. - progressed for careful restoration and accurate study. In Recent years, various professional organizations(in the field of structure, physics, chemistry, biology, lithology, etc.) started to join the researches. Researches conducted studies directly with the stone pagodas, as well as conducting indirect studies with the stone pagodas, such as the structural stability of stone pagodas, the characteristics of rock, and conservation chemicals. Today the research project 'The preservation project of stone cultural property' is being conducted by the National Research Institute of Cultural Heritage. The purpose of this project is to gain more detailed and accurate investigation documents to be provided for the people. In conclusion, researches from various fields must be included in the research. Furthermore, a synthetic study should be done through comparing similar characteristics or different characteristics among many research results.

• 한국환경교육학회지:환경교육
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• 제23권2호
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• pp.46-64
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• 2010

The purpose of this study is to analyze how the contents of education for sustainable development are reflected in the middle school environment curriculum revised in 2007, and to propose how to integrate content for improving sustainable development education. For this, I analyzed the 2007 Revised Environment Curriculum for Middle Schools by using social network analysis which is the useful methodology to understand the relations of contents. Social Network analysis is a useful tool to excavate the forms of structure or relationship and to explain the characteristics of the system that arise through relationships or to explain the units composing the system. When sustainable development education was examined from 3 points of view, it included environmental sustainability, economical sustainability, and social sustainability. I used the 2007 Revised Environment Curriculum for Middle Schools and manual of curriculum for analysis. The results are 1) The biodiversity conservation and energy efficiency have taken most important positions. 2) In case of economical sustainability pillar, sustainable production had been emphasized. 3) In the case of the social sustainability pillar, health improvement are considered significant. 4) The efforts of trying to approach sustainable development education as an integrated curriculum is week. Integrated themes based on the results were developed. Five main themes were the energy and climate change, water resource and environmental pollution, sustainable village and sustainable food production, sustainable city and sustainable production, sustainable tourism and biodiversity. I hope these could function as theme of integrated-content. Based on the results of study, I propose joint researches on scope of sustainable development for environmental education.

• 자원ㆍ환경경제연구
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• 제20권4호
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• pp.761-796
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• 2011

본 연구는 발전부문에서 에너지 정책의 목표인 에너지 안보와 기후변화 대책 간의 상호보완성을 고려하면서 최저 비용을 기준으로 도출된 발전 구성비를 나타내었다. 에너지 안보의 수준을 측정하기 위해 에너지 안보 가격지수를 도입하여 화석연료의 공급 집중도에서 비롯된 안보 위협을 평가하였다. CSC 방법론의 적용을 통해 원자력과 육상풍력이 석탄가스화 복합발전 및 미분탄 화력발전을 대체하는 경우가 비용효율적인 대체안으로 나타났으며, 잠재적인 탄소 감축 가능량 및 안보 개선폭을 확인하였다. 또한 이러한 대체안이 탄소 감축뿐만 아니라 에너지 안보의 개선을 달성하는 상호보완성을 확인하였다. 추가적인 에너지 안보의 개선을 위해서는 화석연료의 해외자원개발을 통한 에너지 자급률을 제고하는 것이 최선의 대안으로 나타났으며, 이를 기반으로 2020년의 특정 목표치를 달성하기 위해 최저 비용을 나타내는 발전구성비를 도출하였다.

• Structural Engineering and Mechanics
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• 제68권6호
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• pp.747-760
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• 2018

In the present study, a methodology for developing fragilities of arch concrete dams to assess their performance against seismic hazards is introduced. Firstly, the probability risk and fragility curves are presented, followed by implementation and representation of the way this method is used. Amirkabir arch concrete dam was subjected to non-linear dynamic analyses. A modified three dimensional rotating smeared crack model was used to take the nonlinear behavior of mass concrete into account. The proposed model considers major characteristics of mass concrete. These characteristics are pre-softening behavior, softening initiation criteria, fracture energy conservation, suitable damping mechanism and strain rate effect. In the present analysis, complete fluid-structure interaction is included to account for appropriate fluid compressibility and absorptive reservoir boundary conditions. In this study, the Amirkabir arch concrete dam is subjected to a set of 8 three-component earthquakes each scaled to 10 increasing intensity levels. Using proposed nonlinear smeared crack model, nonlinear analysis is performed where the structure is subjected to a large set of scaled and un-scaled ground motions and the maximum responses are extracted for each one and plotted. Based on the results, fragility curves were plotted according to various and possible damages indexes. Discrete damage probabilities were calculated using statistical methods for each considered performance level and incremental nonlinear analysis. Then, fragility curves were constructed based on the lognormal distribution assumption. Two damage indexes were introduced and compared to one another. The results indicate that the dam has a proper stability under earthquake conditions at MCE level. Moreover, displacement damages index is more conservative and impractical in the fragility analysis than tensional damage index.

• 농촌계획
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• 제27권2호
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• pp.1-11
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• 2021

In this study, in order to induce landscape-friendly various development plans established at the district level, the contents of landscape plans appearing in domestic laws and systems and related previous studies are reviewed and comparative analysis is performed to advance the district-level landscape plan. The main focus was to explore the institutional methodology for this. The summary of the research results is as follows. First of all, as a result of analysis of the landscape plan content prescribed in the National Territory Planning Act and the enforcement decree of the same Act, the landscape plan content for natural elements and the landscape plan content for artifacts appeared mixed. Next, looking at the analysis results of the landscape plan contents in the Landscape Act, the Enforcement Decree of the same Act, and the landscape plan establishment guidelines, it is analyzed that the content mainly intended to improve the artificial landscape in terms of aesthetics, such as color, lighting, and buildings. Became. As a result of analysis of the landscape plan contents in the district unit plan establishment guidelines, it was found that the contents of the landscape plan for the skyline, night view, color, advertisements, and viewpoints were presented. As a result of the analysis of the landscape plan contents in the preceding study, the plan contents for ecological, recreational, and micro-visual aspects were revealed, and all three aspects aim to establish a landscape plan within the range of minimizing damage to nature. there was. Appeared to be. The results of this study are considered to be able to induce more landscape and nature-friendly district unit plans being conducted at the district level.