• Title/Summary/Keyword: routine problem

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Linear Spectral Mixture Analysis of Landsat Imagery for Wetland land-Cover Classification in Paldang Reservoir and Vicinity

  • Kim, Sang-Wook;Park, Chong-Hwa
    • Korean Journal of Remote Sensing
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    • v.20 no.3
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    • pp.197-205
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    • 2004
  • Wetlands are lands with a mixture of water, herbaceous or woody vegetation and wet soil. And linear spectral mixture analysis (LSMA) is one of the most often used methods in handling the spectral mixture problem. This study aims to test LSMA is an enhanced routine for classification of wetland land-covers in Paldang reservoir and vicinity (paldang Reservoir) using Landsat TM and ETM+ imagery. In the LSMA process, reference endmembers were driven from scatter-plots of Landsat bands 3, 4 and 5, and a series of endmember models were developed based on green vegetation (GV), soil and water endmembers which are the main indicators of wetlands. To consider phenological characteristics of Paldang Reservoir, a soil endmember was subdivided into bright and dark soil endmembers in spring and a green vegetation (GV) endmember was subdivided into GV tree and GV herbaceous endmembers in fall. We found that LSMA fractions improved the classification accuracy of the wetland land-cover. Four endmember models provided better GV and soil discrimination and the root mean squared (RMS) errors were 0.011 and 0.0039, in spring and fall respectively. Phenologically, a fall image is more appropriate to classify wetland land-cover than spring's. The classification result using 4 endmember fractions of a fall image reached 85.2 and 74.2 percent of the producer's and user's accuracy respectively. This study shows that this routine will be an useful tool for identifying and monitoring the status of wetlands in Paldang Reservoir.

Reliability Analysis and Utilization of BIM-based Highway Construction Output Volume (BIM기반 고속도로 공사 물량산출 신뢰성 검토 및 활용)

  • Jung, Guk-Young;Woo, Jeong-Won;Kang, Kyeong-Don;Shin, Jae-Choul
    • Journal of KIBIM
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    • v.3 no.3
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    • pp.9-18
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    • 2013
  • In case of applying the BIM method in the civil engineering of irregularly shaped structure, BIM method began to be introduced in the current building engineering area compared with the expected effects of the relatively high construction productivity has been recognized. In this paper, I have developed quantity calculation algorithms applying it to earthwork and bridge construction, tunnel construction, retaining wall construction, culvert construction and implemented BIM based 3D-BIM Modeling quantity calculation. Structure work in which errors occurred in range between -6.28% ~ 5.17%. Especially, understanding of the problem and improvement of the existing 2D-CAD based of quantity calculation through rock type quantity calculation error in range of -14.36% ~ 13.07% of earthwork quantity calculation. It's benefit and applicability of BIM method in civil engineering. In addition, routine method for quantity of earthwork has the same error tolerance negligible for that of structure work. But, rock type's quantity calculated as the error appears significantly to the reliability of 2D-based volume calculation shows that the problem could be. Through the estimating quantity of earthwork based 3D-BIM, proposed method has better reliability than routine method. BIM, as well as the design, construction, maintenance levels of information when you consider the benefits of integration, the introduction of BIM design in civil engineering and the possibility of applying for the effectiveness was confirmed. In addition, as the beginning phase of information integration, quantity document automation program has been developed for activation of BIM. And automatically enter the program code number, linkage and manual volume calculation program, quantity document automation programs, such as the development is now underway, and step-by-step procedures and methods are presented.

A New Application Technique of Genetic Algorithm for Power Flow (전력조류계산을 위한 새로운 유전알고리즘 적용기법)

  • Park, Sun-Jae;Chae, Myung-Suck;Yim, Han-Suck;Shin, Joong-Rim
    • Proceedings of the KIEE Conference
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    • 1997.07c
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    • pp.790-793
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    • 1997
  • The most of conventional power flow(PF) calculations which adopt the well-known numerical methods such as Newton-Raphson method often diverge in certain critical cases like near the voltage collapse point. Some Approaches have been reported for the application of Genetic Algorithm(GA) to PF problem to overcome the disadvantages mentioned above. This paper presents a new application technique of GA for PF problem, in which some improvements and modifications are made ; modification of fitness function, improvements on crossover method, mutation law and convergence criterion, introduction of reactive power check routine. Some case studies with IEEE 5, 6, 14 bus systems are performed to show the performance of proposed algorithm.

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Conceptualization-oriented Spatial Decision Support System for III-structured Problems (비단순문제 해결을 위한 GIS 향상방안)

  • 김은형
    • Spatial Information Research
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    • v.1 no.1
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    • pp.63-72
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    • 1993
  • The purpose of this research is to determine how the present use of Geographic Information Systems (GISs) can be improved for ill-structured problems in planning and design, While information-oriented GIS technology has proven useful for routine and administrative problems, it is not yet capable of providing information and knowledge interactively within a problem solving process that can be characterized as "ill-structured." This suggests that GIS technology must be embedded wi thin a large problem solving process for ill-structured problems. The hypothesis of this research is that implementation of conceptualization-oriented Spatial Decision Support Systems(SDSSs) will significantly improve the use of GIS technology for ill-structured problems.

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Fake News Checking Tool Based on Siamese Neural Networks and NLP (NLP와 Siamese Neural Networks를 이용한 뉴스 사실 확인 인공지능 연구)

  • Vadim, Saprunov;Kang, Sung-Won;Rhee, Kyung-hyune
    • Proceedings of the Korea Information Processing Society Conference
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    • 2022.05a
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    • pp.627-630
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    • 2022
  • Over the past few years, fake news has become one of the most significant problems. Since it is impossible to prevent people from spreading misinformation, people should analyze the news themselves. However, this process takes some time and effort, so the routine part of this analysis should be automated. There are many different approaches to this problem, but they only analyze the text and messages, ignoring the images. The fake news problem should be solved using a complex analysis tool to reach better performance. In this paper, we propose the approach of training an Artificial Intelligence using an unsupervised learning algorithm, combined with online data parsing tools, providing independence from subjective data set. Therefore it will be more difficult to spread fake news since people could quickly check if the news or article is trustworthy.

The Analysis of Axisymmetric Field Problem by C-1 FEM (C-1 유한요소법에 의한 축대칭장 문제의 해석)

  • Jang, I.K.;Kwak, D.S.;Shin, H.K.
    • Proceedings of the KIEE Conference
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    • 1999.11b
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    • pp.21-23
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    • 1999
  • In this paper, the analysis of the electric field in the chamber of high voltage $SF_6$ GCB(Gas Circuit Breaker) is presented by using C-1 FEM. For this purpose, pre-processing program and post-processing program were developed for axisymmetirc 3 dimensional analysis and the electric field in cylindric chamber was analyzed. Important problem is that electric analysis must be considered coronal due to break-down of $SF_6$ when it is cutted off. To solve this problem, a procedure is needed to verify that the solution of Poisson's equation for scalar potential satisfy charge continuos condition because of using first order element os not satisfy the electric continuous condition, C-1 FEM is introduce to obtain electirc potential and electric field at the same time. Analysis of the distribution of electric field on model was done. It is confirmed that the developed program in this paper applicable to design and to analyze of characteristics in total program as electric characteristics analysis routine.

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Optimal Positioning of Heating Lines in a Compression Molding Die Using the Boundary Element Method (경계요소법을 이용한 압축성형다이 가열선의 최적위치 설계)

  • 이부윤;조종래
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.6
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    • pp.1478-1485
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    • 1993
  • A shape optimization problem is formulated to determine the optimal position of heating lines in a compression molding die. The objective of the problem is that the cavity surface would be maintained by a prescribed uniform temperature. A boundary integral equation for the sensitivity of the temperature in terms of hole position is derived using the method of shape design sensitivity analysis. The boundary element method is employed to analyze the temperature and sensitivity field of the die. The sensitivity calculation algorithm is incorporated in an optimization routine. To demonstrate a numerical implementation, an example problem arising in thermal design of a compression molding die is dealt with, showing that the number of heating lines chosen for the die strongly affects the ultimate uniformity of the cavity surface temperature.

The Effects of Teacher's Beliefs about Mathematics on the Method of Class and the Performance of Problem Solving (교사의 수학에 대한 신념이 수업 방법과 학생의 문제해결 수행에 미치는 영향)

  • 김시년
    • Education of Primary School Mathematics
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    • v.3 no.1
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    • pp.79-88
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    • 1999
  • This paper shows how the social tradition and belief of korea on education affects teachers and students and learning. 1 Interview with teacher. During surveying this teacher's class, we knowed that the teacher have accentuated algorism loaming and preparation fur external examination in math class. Teacher's beliefs about mathematics have a strong effect on the method of class and the performance of problem solving 2. Interview with students and short test. 1) Students usually had fine ability of calculation for number. But Many pupils didn't know the meaning of the operations. 2) The most of pupils are good at routine math problem solving but when the question whose the condition don't meet was given, they experienced difficulties.3.Korean sociocultural specialty on education: The korean place high emphasis on education and think of education as the means of success. This emphasis can be traced to the Confucian view. 1) tradition on examination culture. 2) the traditional convention of the learning method. Korean sociocultural specialty on education play role of strengthen role learning and algorism class. The important things to education reformation are getting a balance between practice and understanding. we should make changes not only in national dimension but also in math class.

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A Study of Neutronics Effects of the Spacer Grids in a Typical PWR via Monte Carlo Calculation

  • Tran, Xuan Bach;Cho, Nam Zin
    • Nuclear Engineering and Technology
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    • v.48 no.1
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    • pp.33-42
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    • 2016
  • Spacer grids play an important role in maintaining the proper form of the fuel assembly structure and ensuring the safety of reactor core design. This study applies the Monte Carlo method to the analysis of the neutronics effects of spacer grids in a typical pressurized water reactor (PWR). The core problem used to analyze the neutronics effects of spacer grids is a modified version of Korea Advanced Institute of Science and Technology benchmark problem 1B, based on an Advanced Power Reactor 1400 (APR1400) core model. The spacer grids are modeled and added to this test problem in various ways. Then, by running MCNP5 for all cases of spacer grid modeling, some important numerical results, such as the effective multiplication factor, the spatial distributions of neutron flux, and its energy spectrum are obtained. The numerical results of each case of spacer grid modeling are analyzed and compared to assess which type has more advantages in accuracy of numerical results and effectiveness in terms of geometry building. The conclusion is that the most realistic modeling for Monte Carlo calculation is the "volume-preserving" streamlined heterogeneous spacer grids, but the "banded" dissolution spacer grids modeling is a more practical yet accurate model for routine (deterministic) analysis.

Slope Stability Analysis by Slice Method and Finite Difference Method- A Comparative Study - (절편법과 유한차분법에 의한 사면안정해석 비교연구)

  • 박연준;채영수;유광호;백영식
    • Journal of the Korean Geotechnical Society
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    • v.15 no.6
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    • pp.263-272
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    • 1999
  • Slice method is commonly used in solving slope stability problems since it is easy to use and its computation time is rather short. But depending upon the assumptions on the inter-slice forces, different methods are available. Quite often the difference between methods are so big that it is very difficult to make engineering decisions. This paper describes a method to calculate the factor of safety of a slope using FLAC, a finite difference based program. A FISH routine is developed to calculate the factor of safety, and verified by comparing with Chen's limit equilibrium solution. An example problem was selected from Fredlund and Krhan's paper, and results were compared for different soil and water conditions. The difference was less than 0.01 when the soil is homogeneous, and less than 5 % when a weak layer is embedded. Since most geotechnical application programs are capable of considering complicated ground conditions as well as the effect of ground supports, numerical methods are believed to be very useful in making engineering decisions. The developed routine can be applied to the calculation of the factor of safety of jointed rock slopes or weathered rock slopes where the use of slice method is limited.

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