• Title/Summary/Keyword: Macroscopic Model

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Conceptual Models for Evaluation of Urban Logistics Improvement (도시물류 개선 대안 평가를 위한 개념적 모형 정립)

  • 허윤수;남기찬;윤항묵
    • Journal of Korean Society of Transportation
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    • v.19 no.5
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    • pp.7-18
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    • 2001
  • This study is concerned with theoretical aspects of urban logistics with the aim of revealing limitations of the literature, suggesting directions for further studies and developing a conceptual model for evaluating policy alternatives. Several limitations have been revealed and, based on these, the directions for further studies were suggested as more effort needs to be put on microscopic aspects of urban logistics ; and integrated conceptual evaluation models need to be developed. For the models it defined microscopic evaluation factors by the subject of urban logistics activities, and with these factors it established a conceptual model. Especially it introduced the simulation models developed recently to predict the route of freight vehicles and suggested how both microscopic and macroscopic aspects of urban logistics could be evaluated.

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Optimal Design of Process-Inventory Network Considering Exchange Rates and Taxes in Multinational Corporations (다국적 기업에서 환율과 세금을 고려한 공정-저장조 망구조의 최적설계)

  • Yi, Gyeong-Beom;Suh, Kuen-Hack
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.9
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    • pp.932-940
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    • 2011
  • This paper presents an integrated analysis of supply chain and financing decisions of multi-national corporation. We construct a model in which multiple currency storage units are installed to manage the currency flows associated with multi-national supply chain activities such as raw material procurement, process operation, inventory control, transportation and finished product sales. Core contribution of this study is to quantitatively investigate the influence of macroscopic economic factors such as exchange rates and taxes on operational decisions. The supply chain is modeled by the Process-Storage Network with recycle streams. The objective function of the optimization is minimizing the opportunity costs of annualized capital investments and currency/material inventories minus the benefit to stockholders interpreted by home currency. The major constraints of the optimization are that the material and currency storage units must not be depleted. A production and inventory analysis formulation, the periodic square wave (PSW) model, provides useful expressions for the upper/lower bounds and average levels of the currency and material inventory holdups. The expressions for the Kuhn-Tucker conditions of the optimization problem are reduced to a subproblem and analytical lot sizing equations. The procurement, production, transportation and financial transaction lot sizes can be determined by analytical expressions after the average flow rates are already known. We show that, when corporate income tax is taken into consideration, the optimal production lot and storage sizes are smaller than is the case when such factors are not considered typically by 20 %.

Invirto alternatives to photosensitization Test (광감작성 시험에서의 동물대체 시험법)

  • Lee, Ho;Nam, Ki-Taek;Koh, Jae-Sook;Park, Won-Jae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.22 no.1
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    • pp.84-101
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    • 1996
  • To minimize the use of animals in toxicity testing, and to reduce the cost in vivo test, more rational test method was described which determines, in the same animal, photoxic and photoallergic potential of a substance, and is daptable to routine testing. The other purpose of this study was to investigate the usefulness of in vivo alternatives ; photostability and spectrophotometric carbonyl assay. In this modified photosensitization model, animal numbers and resting periods, the number and method of topical application were simplified. Two positive photoreactive agents, Benzocaine and 6-methyl coumarine, showed a similar photoallergic potential to that of Ichikawa's method. Two sunscreens, Octyl methoxy cinnamate, Butyl methoxyl dibenzoyl methane, hardly showed photoallergic potentials. The photostability test could be used in the step of prescreening of photosensitization potential because most of the photoreactive agents represented the reduction of more than 20% in the absorbance. And photoreactive agents have a high potential of photosensitization in the sddessment of spectrophotometric carbonyl level although two sunscreens have a low possibility of photosensitization. Therefore this method was assumed as a valuable in vivo alternatives in the respect even in the very low concentrations which phototoxicity test using almonella showed no phototoxic potential.

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Analysis of Characteristics of the Dynamic Flow-Density Relation and its Application to Traffic Flow Models (동적 교통량-밀도 관계의 특성 분석과 교통류 모형으로의 응용)

  • Kim, Young-Ho;Lee, Si-Bok
    • Journal of Korean Society of Transportation
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    • v.22 no.3 s.74
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    • pp.179-201
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    • 2004
  • Online traffic flow modeling is attracting more attention due to intelligent transport systems and technologies. The flow-density relation plays an important role in traffic flow modeling and provides a basic way to illustrate traffic flow behavior under different traffic flow and traffic density conditions. Until now the research effort has focused mainly on the shape of the relation. The time series of the relation has not been identified clearly, even though the time series of the relation reflects the upstream/downstream traffic conditions and should be considered in the traffic flow modeling. In this paper the flow-density relation is analyzed dynamically and interpreted as a states diagram. The dynamic flow-density relation is quantified by applying fuzzy logic. The quantified dynamic flow-density relation builds the basis for online application of a macroscopic traffic flow model. The new approach to online modeling of traffic flow applying the dynamic flow-density relation alleviates parameter calibration problems stemming from the static flow-density relation.

Ideal Housing in the Home Exposition Under the Japanese Colonial Rule (일제강점기 가정박람회에 나타난 이상주거)

  • Yang, Se-Hwa;Ryu, Hyun-Joo;Eun, Nan-Soon
    • Journal of the Korean Home Economics Association
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    • v.47 no.1
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    • pp.45-54
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    • 2009
  • The purpose of the study is to examine the characteristics of the ideal housing for the modern family suggested by the Home Exposition (September, 1915) under the Japanese colonial rule in the macroscopic context of social change and the microscopic context of family. Through this research, we expect to have a partial understanding not only of changes in the outward appearance of traditional housing spaces during the civilization period and the early Japanese colonial rule when foreign cultures began to be introduced but also of families'residential lives and the patterns of change in people's consciousness of housing. Major conclusions from the current analysis are as follows. First, there were some changes in family paradigm induced through a home exhibition. Second, the most important factor for an ideal housing was that it must be the source of harmonic and healthy family life. Third, the importance of an appropriate space norm should be emphasized by providing the minimum size of each room. Fourth, the significance of the housing values of the economy, convenience, and hygiene should be emphasized for the ideal housing. Lastly, it was implied that for an ideal housing, the social and psychological aspects of housing must be satisfied along with the physical aspects. The limitation was that the model of ideal family housing presented in the Home Exposition cannot exclude the characteristics of the colonial perspectives in that it was followed by the model for the Japanese families.

Framework of Ship PLM System Based Upon Four-Tier Model (4-계층 모델 기반의 선박 수명주기관리 시스템 프레임워크)

  • Kim, Seung-Hyun;Lee, Jang-Hyun;Lee, Kyung-Ho;Suh, Heung-Won
    • Korean Journal of Computational Design and Engineering
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    • v.15 no.5
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    • pp.362-374
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    • 2010
  • Product Lifecycle Management (PLM) is an integrated business approach to manage the creation and distribution of product information throughout the product development process. From the product perspective, PLM encompasses a holistic approach to product development and product information management. It supports the integrated product information in conjunction with the efficient product structures and BOM (Bill Of Material), user interfaces, proper functions, design processes and enterprise integration. Therefore, PLM should not only satisfy required functions as an enterprise software but also offer a systematic method for the efficient application from the initial stage of its development. Recently, many shipyards have been considering the PLM as a strategic solution to get the efficient management of product information such as 3-D models, BOM, drawings, documents, and the other product data. Though many studies on PLM are performed, most of them are performed in a function-based approach adequate for mass productive assembly industries. It could not help having limitations on applying the proper PLM system to the shipbuilding business since the requirements of shipbuilding PLM are too diverse and huge to design the architecture. This study presents the PLM framework which effectively reflects the diverse requirements of shipbuilding PLM. In order to get the macroscopic architecture of shipbuilding PLM, authors suggest the four-tier architecture model which considers the various requirements collected from shipyards. Entities of ship design data are modeled BOM in terms of product structure and hierarchical class diagram. Applicable functions of shipbuilding PLM are also investigated by analysis of issues of ship design. Finally, by reflecting the design process of shipbuilding, To-Be ship design procedure cooperated with the suggested PLM framework has been summarized.

Granulocyte Colony Stimulating Factor (G-CSF) Attenuates 2,4,6-Trinitrobenzene Sulfonic Acid (TNBS)-induced Colitis in Mice (마우스 염증성 장 질환 모델에서 G-CSF (Granuocyte Colony Stimulating Factor)에 의한 염증 완화)

  • Choi, Eun-Young;Jun, Chang-Duk;Oh, Jae-Min;Kim, Yu-Rim;Lee, Soo-Teik;Kim, Sang-Wook
    • IMMUNE NETWORK
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    • v.6 no.1
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    • pp.13-19
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    • 2006
  • Background: Granulocyte colony stimulating factor (G-CSF) is known as a cytokine central to the hematopoiesis of blood cells and to modulate their cellular functions. Besides granulocytes and their precursors, monocytes/macrophages and endothelial cells are direct target cells of G-CSF action. G-CSF influences immune cells in an anti inflammatory way. Methods: To evaluate whether G-CSF has a potential for preventing or ameliorating diseases characterized by mucosal inflammation, we used a mouse model with trinitrobenzene sulfonic acid (TNBS)-induced inflammatory colitis. To the mice model G-CSF was administrated daily by intraperitoneal injection. Macroscopic evaluation and immunohistochemical analysis of colonic tissues were performed. Results: Re combinant human G-CSF significantly inhibited LPS-induced TNF-${\alpha}$ mRNA expression in THP-1 cells. As for in vivo relevance, G-CSF dramatically reduced the weight loss of mice, colonic damage, and mucosal ulceration that characterize TNBS colitis. Moreover, G-CSF suppressed the expression of tumor necrosis factor-${\alpha}$, interleukin-$1{\beta}$, and intercellular adhesion molecule-1 in TNBS colitis. Conclusion: Current results demonstrate that G-CSF may be an effective agent for the treatment of diseases characterized by mucosal inflammation.

Application of the HELIOS-MASTER Code System on the Criticality Analysis for the SMART-P Spent Fuel Storage (SMART연구로 사용후 연료 저장조의 임계해석에 HELIOS-MASTER계산체계의 적용)

  • Kim, Ha-Yong;Koo, Bon-Seung;Kim, Kyo-Youn;Lee, Chung-Chan;Zee, Sung-Quun
    • Journal of Radiation Protection and Research
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    • v.30 no.2
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    • pp.61-67
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    • 2005
  • The criticality analysis method using HELIOS-MASTER code system, which is the nuclear core analysis code system, was developed for the spent fuel storage of SMART-P reactor. We generated the macroscopic cross section of the geometric model with HELIOS and estimated the criticality of the 3-dimensional model with MASTER for SMART-P spent fuel storage. The validity of criticality analysis method for SMART-P spent fuel storage with the HELIOS-MASTER code system by 3-D MCNP calculation was also verified. The result of the criticality analysis with the HELIOS-MASTER code system is more conservative than that with the MCNP and the accuracy of this result is within the range of an allowable error. Because HELIOS-MASTER can perform the 3-D depletion calculation lot a spent fuel storage, it will be useful to perform the criticality analysis including a burnup credit in future.

Multiscale Analysis on Vibration of the Photo Responsive Polymer (광변형 고분자의 동적 진동에 관한 멀티스케일 해석)

  • Yun, Jung-Hoon;Li, Chenzhe;Chung, Hayoung;Choi, Joonmyung;Cho, Maenghyo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.29 no.6
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    • pp.571-575
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    • 2016
  • Photo responsive polymer(PRP) is well known for its photo deformation under UV light, and goes back to its original shape in visible light due to the photoisomerization of the azobenzene inside the PRP. In this paper, dynamic study of the vibration in PRP is discussed. In order to predict photo-deformation of the PRP a multiscale modeling is introduced which covers quantum level photo excitation, microscopic morphology, and macroscopic deformation of the PRP. A simple 1D beam model is introduced to model dynamic bending behavior of the PRP. Through fast Fourious transformation analysis, we identify that vibration frequency of the PRP can be controlled by light polarization angle.

Hysteresis Loops, Critical Fields and Energy Products for Exchange-spring Hard/soft/hard Trilayers

  • Chen, B.Z.;Yan, S.;Ju, Y.Z.;Zhao, G.P.;Zhang, X.C.;Yue, M.;Xia, J.
    • Journal of Magnetics
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    • v.20 no.1
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    • pp.31-39
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    • 2015
  • Macroscopic hysteresis loops and microscopic magnetic moment distributions have been determined by a three-dimensional (3D) model for exchange-coupled Sm-Co/${\alpha}-Fe$/Sm-Co trilayers with in-plane collinear easy axes. These results are carefully compared with the popular one-dimensional (1D) micromagnetic models and recent experimental data. It is found that the results obtained from the two methods match very well, especially for the remanence and coercivity, justifying the calculations. Both nucleation and coercive fields decrease monotonically as the soft layer thickness $L^s$ increases while the largest maximum energy product (roughly 50 MGOe) occurs when the thicknesses of hard and soft layers are 5 nm and 15 nm, respectively. Moreover, the calculated angular distributions in the thickness direction for the magnetic moments are similar. Nevertheless, the calculated nucleation and pinning fields as well as the energy products by 3D OOMMF are systematically smaller than those given by the 1D model, due mainly to the stray fields at the corners of the films. These demagnetization fields help the magnetic moments at the corners to deviate from the previous saturation state and facilitate the nucleation. Such an effect enhances as $L^s$ increases. When the thicknesses of hard and soft layers are 10 nm and 20 nm, respectively, the pinning field difference is as large as 30%, while the nucleation fields have opposite signs.