• Title/Summary/Keyword: Concept models

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Virtual Path Routing Optimization in ATM Network (ATM 망의 가상경로 루팅 최적화)

  • 박구현
    • Journal of the Korean Operations Research and Management Science Society
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    • v.20 no.1
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    • pp.35-54
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    • 1995
  • Routing in ATM network is set up by combination of both virtual path routing and virtual channel routing. While virtual channel is similar concept to virtual circuit of data networks, virtual path is a special concept which is not used in traditional data networks. Virtual path can rearrange in structure and size by simply changing virtual path routing tables and giving the network the capability to eash allocate network resources according to the demand needs. This paper provides reconfiguration models of virtual path network which give the bandwidth of link and the routing path for each traffic class. The reconfiguration models are network optimization problems of multicommodity network flow type. The numerical examples are also included.

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The comparative study of Chinese Design Higher Education before and after the Reform and Opening-up

  • Jiang, Zheng-Qing;Lee, Dong-Hun
    • International Journal of Contents
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    • v.6 no.4
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    • pp.43-48
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    • 2010
  • Because of the social and political reasons, Chinese design higher education has come a long and difficult road. Before and after the Reform and Opening-up, Chinese design higher education system has gone through two different models: "Arts and Crafts" and "Arts & Design". By comparing external environment and Education Concept of two models, this paper points out that the correct direction of design higher education reform is to understand and learn the advantages of two education systems.

An application of damage detection technique to the railway tunnel lining (철도터널 라이닝에 대한 손상도 파악기법의 현장적용)

  • Bang Choon-seok;Lee Jun S.;Choi Il-Yoon;Lee Hee-Up;Kim Yun Tae
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.1142-1147
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    • 2004
  • In this study, two damage detection techniques are applied to the railway tunnel liner based on the static deformation data. Models based on uniform reduction of stiffness and smeared crack concept are both employed, and the efficiency and relative advantage are compared with each other. Numerical analyses are performed on the idealized tunnel structure and the effect of white noise, common in most measurement data, is also investigated to better understand the suitability of the proposed models. As a result, model 1 based on uniform stiffness reduction method is shown to be relatively insensitive to the noise, while model 2 with the smeared crack concept is proven to be easily applied to the field situation since the effect of stiffness reduction is rather small. Finally, real deformation data of a rail tunnel in which health monitoring system is in operation are introduced to find the possible damage and it is shown that the prediction shows quite satisfactory result.

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A Prediction of DI Diesel engine Performance using the Multizone Model (Multizone 모델을 이용한 직접분사식 디젤엔진 성능 예측에 관한 연구)

  • ;Liu Shenghua
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.1
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    • pp.40-47
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    • 2000
  • A model for the prediction of combustion and exhaust emissions of DI diesel engine has been formulated and developed. This model is a quasi-dimensional phenomenological one and is based on multi-zone combustion modelling concept. This model is developed based on the concept of Hiroyasu's multizone combustion models. It takes nozzle injection (spray) parameters, induction swirl into consideration and the models of zone velocity, air entrainment, fuel droplet evaporation and mixture combustion are upgraded. Various parameters, such as cylinder pressure, heat release rate, Nox and soot emission, and these parameters in the zone are simulated. The results are compared with the experimental ones, too.

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Models and Modeling Behavior: A Look at the Critical Thinking Skills of Biology Majors

  • Partosa, Jocelyn D.
    • Journal of The Korean Association For Science Education
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    • v.32 no.8
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    • pp.1281-1294
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    • 2012
  • This paper describes the types of models that biology majors use and how they go about making their models in learning key concepts in biology such as the cell membrane, cytoskeleton and cell structure. Initially, a total of 44 biology students from all year levels enrolled in the second semester of calendar year 2008-2009 were asked to make their respective models of the cell membrane, cytoskeleton and cell structure. They were also asked to answer an open-ended questionnaire. Of the 44, only 20 (five from each year level) were randomly selected for a one-on-one interview. Results showed that the student-generated models from all year levels were mostly analogies, some textbook definitions and occasional drawings. In making their model, students first read the text; second, outline similarities in structure and function or both; and third, make the model. Data suggest that models are good diagnostic tools for identifying critical thinking skills of students. In this case, students mostly demonstrate the ability to recognize similarities in structure and function between the concept and their model. Some senior students demonstrated integration and reflective thinking in making their models. Thus, more opportunities for student-generated models must be available if students were to develop integration and reflective thinking in their models.

Trends of Concept Development in Nursing Published in Korean Journals (국내 학술지에 게재된 간호개념개발 연구의 동향)

  • Lee, Sumi;Lee, Jinhae;Hwang, Yugyeong;Ko, Il Sun
    • Journal of Korean Academy of Nursing
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    • v.50 no.2
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    • pp.178-190
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    • 2020
  • Purpose: The purpose of this study was to identify trends of nursing concept development in Korean journal papers to improve accurate understanding of nursing concepts. Methods: A systematic review of 216 concept development articles published from 1970 to 2018 that met the inclusion criteria was conducted using Research Information Sharing Service (RISS) databases. Results: The most common method of concept development was Walker and Avant's concept analysis method, identified in 139 (64.3%) of the 216 studies, followed by 48 examples of hybrid models (22.2%) and 15 examples of evolutionary methods (6.9%). Chinn and Kramer's method, Norris's clarification, Wilson's method, and others were also used. The concepts of "spirituality" and "fatigue" were most frequently analyzed. Among the 139 studies that used Walker and Avant's concept analysis method, 127 studies (91.4%) applied all the recommended steps; the others applied the recommended steps partially, omitting description of model cases/additional cases, antecedents/consequences, and empirical indicators. Among the studies using the hybrid model, among two (5.7%) did not describe attributes, three (8.5%) did not provide definitions, and 16 (45.7%) did not present empirical indicators in the final stage. Conclusion: Among concept development studies published in Korean journals, Walker and Avant's concept analysis method is most commonly used. In case of most studies using Walker and Avant's method a suitable concept analysis process is applied, but in case of other studies using the other concept development method, a suitable concept analysis process is not applied. Therefore, a suitable concept analysis process must be applied for concept development in nursing research.

A SCORM-based e-Learning Process Control Model and Its Modeling System

  • Kim, Hyun-Ah;Lee, Eun-Jung;Chun, Jun-Chul;Kim, Kwang-Hoon Pio
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.11
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    • pp.2121-2142
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    • 2011
  • In this paper, we propose an e-Learning process control model that aims to graphically describe and automatically generate the manifest of sequencing prerequisites in packaging SCORM's content aggregation models. In specifying the e-Learning activity sequencing, SCORM provides the concept of sequencing prerequisites to be manifested on each e-Learning activity of the corresponding tree-structured content organization model. However, the course developer is required to completely understand the SCORM's complicated sequencing prerequisites and other extensions. So, it is necessary to achieve an efficient way of packaging for the e-Learning content organization models. The e-Learning process control model proposed in this paper ought to be an impeccable solution for this problem. Consequently, this paper aims to realize a new concept of process-driven e-Learning content aggregating approach supporting the e-Learning process control model and to implement its e-Learning process modeling system graphically describing and automatically generating the SCORM's sequencing prerequisites. Eventually, the proposed model becomes a theoretical basis for implementing a SCORM-based e-Learning process management system satisfying the SCORM's sequencing prerequisite specifications. We strongly believe that the e-Learning process control model and its modeling system achieve convenient packaging in SCORM's content organization models and in implementing an e-Learning management system as well.

Development of Empirical Space Weather Models based on Solar Information

  • Moon, Yong-Jae;Kim, Rok-Soon;Park, Jin-Hye;Jin, Kang
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.90.1-90.1
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    • 2011
  • We are developing empirical space weather (geomagnetic storms, solar proton events, and solar flares) forecast models based on solar information. These models have been set up with the concept of probabilistic forecast using historical events. Major findings can be summarized as follows. First, we present a concept of storm probability map depending on CME parameters (speed and location). Second, we suggested a new geoeffective CME parameter, earthward direction parameter, directly observable from coronagraph observations, and demonstrated its importance in terms of the forecast of geomagnetic storms. Third, the importance of solar magnetic field orientation for storm occurrence was examined. Fourth, the relationship among coronal hole-CIR-storm relationship has been investigated, Fifth, the CIR forecast based on coronal hole information is possible but the storm forecast is challenging. Sixth, a new solar proton event (flux, strength, and rise time) forecast method depending on flare parameters (flare strength, duration, and longitude) as well as CME parameter (speed, angular width, and longitude) has been suggested. Seventh, we are examining the rates and probability of solar flares depending on sunspot McIntosh classification and its area change (as a proxy of flux change). Our results show that flux emergence greatly enhances the flare probability, about two times for flare productive sunspot regions.

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Development of Boolean Operations for CAD System Kernel Supporting Non-manifold Models (비다양체 모델을 수용하는 CAD 시스템 커널을 위한 불리안 조직의 개발)

  • 김성환;이건우;김영진
    • Korean Journal of Computational Design and Engineering
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    • v.1 no.1
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    • pp.20-32
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    • 1996
  • The boundary evaluation technique for Boolean operation on non-manifold models which is regarded as the most popular and powerful method to create and modify 3-D CAD models has been developed. This technique adopted the concept of Merge and Selection in which the CSG tree for Boolean operation can be edited quickly and easily. In this method, the merged set which contains complete information about primitive models involved is created by merging primitives one by one, then the alive entities are selected following the given CSG tree. This technique can support the hybrid representation of B-rep(Boundary Representation) and CSG(Constructive Solid Geometry) tree in a unified non-manifold model data structure, and expected to be used as a basic method for many modeling problems such as data representation of form features, and the interference between them, and data representation of conceptual models in design process, etc.

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Two Uncertain Programming Models for Inverse Minimum Spanning Tree Problem

  • Zhang, Xiang;Wang, Qina;Zhou, Jian
    • Industrial Engineering and Management Systems
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    • v.12 no.1
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    • pp.9-15
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    • 2013
  • An inverse minimum spanning tree problem makes the least modification on the edge weights such that a predetermined spanning tree is a minimum spanning tree with respect to the new edge weights. In this paper, the concept of uncertain ${\alpha}$-minimum spanning tree is initiated for minimum spanning tree problem with uncertain edge weights. Using different decision criteria, two uncertain programming models are presented to formulate a specific inverse minimum spanning tree problem with uncertain edge weights involving a sum-type model and a minimax-type model. By means of the operational law of independent uncertain variables, the two uncertain programming models are transformed to their equivalent deterministic models which can be solved by classic optimization methods. Finally, some numerical examples on a traffic network reconstruction problem are put forward to illustrate the effectiveness of the proposed models.