• Title/Summary/Keyword: 구획 모델

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Simplified Approximation Method of the Multi-Compartments Model on the Migration of Contaminant through Unsaturated Zone (불포화대에서 오염물질 이동현상에 대한 다중구획 모델의 단순 근사방법)

  • Cheong, Jae-Hak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.1
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    • pp.29-37
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    • 2007
  • A conventional single compartment model cannot simulate reasonably the migration phenomenon of contaminants through unsaturated zone, due to the intrinsic unrealistic assumption of the compartment model that contaminants entering a compartment are immediately and uniformly mixed. Although, a multi-compartments model, in which even physically identical layer is divided into multiple compartments, may be used for explaining the retardation of contaminant mass flux along with increasing number of compartments, its numerical modeling is usually time-consuming and appropriate analytical solutions have not been reported yet. In order to improve the conventional compartment models on contaminant migration through unsaturated zone, a series of analytical solutions for multi-compartments model were derived and a generalized constraint under which the results from multi-compartments model can be simply approximated by single compartment model was proposed. The simplified approximation method was verified by a simple numerical analysis on the constraint under hypothetical conditions. It was also proved that the influent contaminant transfer rate from the bulk unsaturated zone can be generally represented into a time-dependent nominal transfer rate rather than a constant. In addition, the nominal transfer rate turned out to be very sensitive to the contaminant transfer rate between compartments in unsaturated zone, but to be almost insensitive to the transfer rate from contaminated zone. It is expected that the simplified approximation method developed in this study can be used for rapid and reasonable estimation of the migration phenomenon of contaminant through unsaturated zone, instead of time-consuming multi-compartments modeling.

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A Study on the Interactive Ship Compartmentation Modelling Technique Using Graphical User Interface (그래픽 지원 대화식 구획배치 모델링에 관한 연구)

  • W.S. Kang;K.Y. Lee
    • Journal of the Society of Naval Architects of Korea
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    • v.31 no.4
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    • pp.23-31
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    • 1994
  • The compartmentation model is represented by the characteristics and geometric information of the spaces defined by the structural members which are used for the boundary planes of the compartment. For the efficient compartment modeling a program performing the compartmentation design by the chopping and merging method was presented by authors. In this research, the development of an interactive ship compartmentation modeller is introduced. It is natural that the value of the program lessens if the input process is complicated and uneasy, even though the internal techniques for the compartmentation modeling are superior. In this paper, a method for the convenient input is proposed and implemented with the help of a graphical user interface technique. The modeling method introduced in this paper performs an efficient compartmentation modeling fast and conveniently by the solid modeling concept and the graphical user interface.

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Modeling Study on Nuclide Transport in Ocean - an Ocean Compartment Model (해양에서의 핵종이동 모델링 - 해양구획 모델)

  • Lee, Youn-Myoung;Suh, Kyung-Suk;Han, Kyong-Won
    • Nuclear Engineering and Technology
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    • v.23 no.4
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    • pp.387-400
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    • 1991
  • An ocean compartment model simulating transport of nuclides by advection due to ocean circulation and intertaction with suspended sediments is developed, by which concentration breakthrough curves of nuclides can be calculated as a function of time. Dividing ocean into arbitrary number of characteristic compartments and performing a balance of mass of nuclides in each ocean compartment, the governing equation for the concentration in the ocean is obtained and a solution by the numerical integration is obtained. The integration method is specially useful for general stiff systems. For transfer coefficients describing advective transport between adjacent compartments by ocean circulation, the ocean turnover time is calculated by a two-dimensional numerical ocean model. To exemplify the compartment model, a reference case calculation for breakthrough curves of three nuclides in low-level radioactive wastes, Tc-99, Cs-137, and Pu-238 released from hypothetical repository under the seabed is carried out with five ocean compartments. Sensitivity analysis studies for some parameters to the concentration breakthrough curves are also made, which indicates that parameters such as ocean turnover time and ocean water volume of compartments have an important effect on the breakthrough curves.

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On a Compartment Layout Computer Model and Associated Data Structure (선박 구획배치 전산모델과 그 자료구조에 관한 연구)

  • Yong-Chul,Kim;Kyu-Yeul,Lee
    • Bulletin of the Society of Naval Architects of Korea
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    • v.27 no.3
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    • pp.117-126
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    • 1990
  • In the early stage of ship design process large number of alternative compartment layout designs are generated and examined iteratively. Therefore, the design efficiency will be considerably enhanced if a tool is available to perform this kind of iterative design process effectively in a relatively short time. This paper describes a method for generating and evaluating various alternative compartment layout designs in a personal computer. In this method, computer model of a compartment layout is generated by establishing the hierarchical structure of the entities forming a compartment and defining clearly the relationships among the entities. The evaluation of the design alternatives are effectively performed utilizing the computer model generated. The data structure for storing the defined compartment layout is explained and an illustrative example is given showing the application of the method to the design and evaluation of compartment layout of an Oceanographic Research Vessel.

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Interregional Epidemic Model with Multi-Group Compartmental Model (다 집단 구획모델을 적용한 지역 간 감염모델)

  • Gwak, Seung Hyun
    • Journal of the Korea Society for Simulation
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    • v.30 no.3
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    • pp.19-29
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    • 2021
  • To explain the interregional infections in COVID-19, we designed a multi-group compartmental model by applying the SEIQRD model, a compartmental model of a single group. The model is segmented by compartments to account for hidden infections, such as latent periods and asymptomatic cases, and is capable of comparing infection indices and test rates between regions. Through this, it estimated which region was centered during the second wave in August 2020 and the third wave in November 2020. Subgroups were set up in Seoul, Gyeonggi (including Incheon), and a non-metropolitan area. We fit the model to the Ministry of Health and Welfare's data to estimate the average infection index between regions, average rate of rT-PCR test by region, and the expected number of hidden infections by region.

A Study on Analysis of Atmospheric Behavior of PCBs by an One-compartment Box Model (단일 구획상자모델을 이용한 PCBs의 대기 중 거동 해석에 관한 연구)

  • Kim, Kyoung-Soo
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.7
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    • pp.713-720
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    • 2006
  • To analyze atmospheric fate of PCBs in the Kanto region, Japan, an one-compartment box model was used and the relationship between behavior of each PCB homologue and air temperature was simulated. In addition, the emission rates and the deposition fluxes in the overall Kanto region were estimated by the model. The total emission rate and deposition flux was 3,320 kg/yr and 1,480 kg/yr, respectively. The contribution of advection was ranged from 22 to 38% among elimination processes(advection, dry & wet deposition and degradation) of PCBs from atmosphere. The rates of degradation(OH radical process) for PCBs in the Kanto region would be negligible. This study showed that one-compartment box model can be available to understand the overall atmospheric behavior of PCBs.

Development of Robust Semantic Segmentation Modeling on Various Wall Cracks (다양한 외벽에 강인한 균열 구획화 모델 개발)

  • Lee, Soo Min;Kim, Gyeong-Yeong;Kim, Dong-Ju
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2022.07a
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    • pp.49-52
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    • 2022
  • 건물 외벽에 발생하는 균열은 시설물 구조 안전에 영향을 미치며 그 크기에 따라 위험도가 달라진다. 이에 따라 전문검사관의 현장 점검을 통해 발생 균열 두께를 정밀하게 측정할 필요가 있고 최근에는 이러한 현장 안전점검에 인공지능을 도입하려는 추세다. 그러나 기존의 균열 데이터셋은 주로 콘크리트에만 한정되어 다양한 외벽에 강인한 모델을 구축하기 어렵고 균열 두께를 측정하기 위해 정확한 마스크(Mask) 정보가 필요하나 이를 만족하는 데이터셋이 부재하다. 본 논문에서는 다양한 외벽에 강인한 균열 구획화 모델을 목적으로 2,744장의 이미지를 촬영하고 매직 완드 기법으로 라벨링을 진행해 데이터셋을 구축 후, 이를 바탕으로 딥러닝 기반 균열 구획화 모델을 개발했다. UNet-ResNet50을 최종모델로 선정 및 개발 결과, 테스트 데이터셋에 대해 81.22%의 class IoU 성능을 보였다. 본 연구의 기술을 바탕으로 균열 두께를 측정하여 건축물 안전점검에 활용될 수 있기를 기대한다.

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A Case Study of Spatial Allocation of Cut Blocks Using a Timber Harvest Simulator HARVEST (산림수확 시뮬레이터 HARVEST 응용에 의한 벌채지 공간배치 사례연구)

  • Song, Jungeun;Jang, Kwangmin;Han, Hee;Seol, Ara;Chung, Woodam;Chung, Joosang
    • Journal of Korean Society of Forest Science
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    • v.101 no.1
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    • pp.96-103
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    • 2012
  • In this study, we used HARVEST, a timber management strategy assessment tool, to evaluate alternative forest planning strategies on spatial pattern of cutting blocks. We applied the tool to the Gwangreung Experimental Forest (GEF) as a case study. The harvest schedules developed for GEF using a linear programming model was used to assess spatial patterns of cutting blocks under different management constraints. The results show that the allowable maximum harvest size largely affects the number, size, and distribution of cutting blocks. We also found that spatial dispersion methods and adjacency constraints could be used as an effective means to control spatial allocation of cutting blocks in order to meet certain forest ecosystem management goals.

An Optimization Model Based on Combining Possibility of Boundaries for Districting Problems (경계 결합 가능성 기반 구역설정 최적화 모델)

  • Kim, Kamyoung
    • Journal of the Korean Geographical Society
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    • v.49 no.3
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    • pp.423-437
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    • 2014
  • Districting is a spatial decision making process to make a new regional framework for affecting human activities. Natural barriers such as rivers and mountains located within a reorganized district may reduce the efficiency of reorganized human activities. This implies that it is necessary to consider boundary characteristics in a districting process. The purpose of this research is to develop a new spatial optimization model based on boundary characteristics for districting problems. The boundary characteristics are evaluated as continuous value expressing the possibility of combining adjacent two basic spatial units rather than a dichotomous value with 1 or 0 and are defined as an objective function in the model. In addition, the model has explicitly formulated contiguity constraints as well as constraints enforcing demand balance among districts such as population and area. The boundary attributes are categorized into physical and relational characteristics. Suitability analysis is used to combine various variables related to each boundary characteristic and to evaluate the coupling possibility between two neighboring basic units. The model is applied to an administrative redistricting problem. The analytical results demonstrate that various boundary characteristics could be modeled in terms of mixed integer programming (MIP).

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The Representation Methodology for Object-Oriented Ship Compartmentation (객체 지향 선박 구획 정의 표현 방법론)

  • W.S. Kang;S.W. Suh;K.Y. Lee
    • Journal of the Society of Naval Architects of Korea
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    • v.30 no.3
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    • pp.16-28
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    • 1993
  • The object-oriented paradigm is being recognized as the most effective technique to develope the complex, large software system. In this paper, we propose the modeling methodology using object-oriented technology for the ship compartmentation design(OO _COMDEF) based on the proposed modeling methodology. Illustrative examples to show the application of the prototype system are given.

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