• Title/Summary/Keyword: Feasible region

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A Study on the Optimization of Stowage Planning for Container Terminal Considered by Hatch (Hatch를 고려한 컨테이너 터미널 적재순서 최적화 연구)

  • Lee, Sang-Heon;Kim, Moon-Gyu;Ahn, Tae-Ho
    • IE interfaces
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    • v.19 no.4
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    • pp.270-280
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    • 2006
  • The shipping plan for an efficient augmentation of terminal is NP-hard problem which is subordinate to a shipping quantity. The load location problem and stowage planning problem are two important tactical problems for the efficient operations of container terminals. This paper is concerned with reduction of feasible region in constraints for stowage planning. After designing model which minimizes the number of shifting and the travel distance of the transfer crane, the simulated annealing algorithm is employed to search optimal solution quickly and accurately. In order to apply more realistic approach, the partial restriction through adding hatch is complemented to stowage planning decision problem applied in cluster. A variety of numerical experiments demonstrated that solutions by simulated annealing algorithm are useful and applicable in practice.

Site-Specific Growth of Width-Tailored Graphene Nanoribbons on Insulating Substrates

  • Song, U-Seok;Kim, Yu-Seok;Jeong, Min-Uk;Park, Jong-Yun;An, Gi-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.145.2-145.2
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    • 2013
  • The band-gap opening in graphene is a key factor in developing graphene-based field effect transistors. Although graphene is a gapless semimetal, a band-gap opens when graphene is formed into a graphene nanoribbon (GNR). Moreover, the band-gap energy can be manipulated by the width of the GNR. In this study, we propose a site-specific synthesis of a width-tailored GNR directly onto an insulating substrate. Predeposition of a diamond-like carbon nanotemplate onto a SiO2/Si wafer via focused ion beam-assisted chemical vapor deposition is first utilized for growth of the GNR. These results may present a feasible route for growing a width-tailored GNR onto a specific region of an insulating substrate.

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Mathematical Programming Models for Establishing Dominance with Hierarchically Structured Attribute Tree (계층구조의 속성을 가지는 의사결정 문제의 선호순위도출을 위한 수리계획모형)

  • Han, Chang-Hee
    • Journal of the military operations research society of Korea
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    • v.28 no.2
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    • pp.34-55
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    • 2002
  • This paper deals with the multiple attribute decision making problem when a decision maker incompletely articulates his/her preferences about the attribute weight and alternative value. Furthermore, we consider the attribute tree which is structured hierarchically. Techniques for establishing dominance with linear partial information are proposed in a hierarchically structured attribute tree. The linear additive value function under certainty is used in the model. The incompletely specified information constructs a feasible region of linear constraints and therefore the pairwise dominance relationship between alternatives leads to intractable non-linear programming. Hence, we propose solution techniques to handle this difficulty. Also, to handle the tree structure, we break down the attribute tree into sub-trees. Due to there cursive structure of the solution technique, the optimization results from sub-trees can be utilized in computing the value interval on the topmost attribute. The value intervals computed by the proposed solution techniques can be used to establishing the pairwise dominance relation between alternatives. In this paper, pairwise dominance relation will be represented as strict dominance and weak dominance, which ware already defined in earlier researches.

Analytical design of constraint handling optimal two parameter internal model control for dead-time processes

  • Tchamna, Rodrigue;Qyyum, Muhammad Abdul;Zahoor, Muhammad;Kamga, Camille;Kwok, Ezra;Lee, Moonyong
    • Korean Journal of Chemical Engineering
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    • v.36 no.3
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    • pp.356-367
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    • 2019
  • This work presents an advanced and systematic approach to analytically design the optimal parameters of a two parameter second-order internal model control (IMC) filter that satisfies operational constraints on the output process, the manipulated variable as well as rate of change of the manipulated variable, for a first-order plus dead time (FOPDT) process. The IMC parameters are designed to minimize a control objective function composed of the weighted sum of the error between the process variable and the set point, and the rate of change of the manipulated variable, and to satisfy the desired constraints. The feasible region of the constrained IMC control parameters was graphically analyzed, as the process parameters and the constraints varied. The resulting constrained IMC control parameters were also used to find the corresponding industrial proportional-integral controller parameters of a Smith predictor structure.

Dynamic evaluation of water source safety based on fuzzy extension model

  • Ou, Bin;Gong, Aimin;He, Chunxiang;Fu, Shuyan
    • Membrane and Water Treatment
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    • v.10 no.2
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    • pp.149-154
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    • 2019
  • The information matter-element system was built to assess safety of water source. Based on the thought of multiindex fusion, fuzzy matter-element model evaluating water source behavior was constructed by matter-element transform. This model can process comprehensively hydrogeological data, ecological environment, water pollution, surface disturbance, and so on. Water source safety behavior can be described by the qualitative and quantitative manners. According to the development trend of quantitative results, water source safety behavior can be expressed dynamically. As an example, the proposed method was used to assess safety status of 7 water sources in the region. The numerical example shows that the proposed method is feasible and effective, and the evaluation results are reasonable.

Resource Assessment of Theoretical Potential of Ocean Energy in Korea (국내 해양에너지 이론적 잠재량 산정 연구)

  • HWANG, SUJIN;JO, CHULHEE
    • Transactions of the Korean hydrogen and new energy society
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    • v.30 no.5
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    • pp.465-472
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    • 2019
  • This paper describes the resource assessment of theoretical potential of ocean energy including tidal current energy, tidal range energy, wave energy and ocean thermal energy in Korea to provide reliable basis for feasible development plan of ocean energy. Because of different characteristics of each ocean energy resources, the resource assessment methods were established considering characteristics of each ocean energy resources. The coastal region of Korea has been divided into 10 regions. The results show that tidal current energy is abundant in Incheon-Gyunggi and Jeollanam-do and tidal range energy is abundant in Incheon-Gyunggi. And wave energy is abundant in Jeollanam-do, Jeju and Gyeongsangbuk-do and there is ocean thermal energy in Gangwon-do and Gyeongsangbuk-do.

The feasibility of immediately loading dental implants in edentulous jaws

  • Henningsen, Anders;Smeets, Ralf;Wahidi, Aria;Kluwe, Lan;Kornmann, Frank;Heiland, Max;Gerlach, Till
    • Journal of Periodontal and Implant Science
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    • v.46 no.4
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    • pp.234-243
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    • 2016
  • Purpose: Immediate loading of dental implants has been proved to be feasible in partially edentulous jaws. The purpose of this retrospective investigation was to assess the feasibility of immediately loading dental implants in fully edentulous jaws. Methods: A total of 24 patients aged between 53 and 89 years received a total of 154 implants in their edentulous maxillae or mandibles. Among the implants, 45 were set in fresh extracted sockets and 109 in consolidated alveolar bones. The implants were provisionally managed with chair-side made provisional resin bridges and exposed to immediate loading. Implants were followed up for 1-8 years, including radiographic imaging. Marginal bone levels were evaluated based on radiographic imaging. Results: A total of 148 out of the 154 implants survived over the follow-up period of 1 to 8 years, giving a survival rate of 96%. The time or region of the implantation, the pre-implant augmentation, and the length and diameter of the implants had no statistically significant influence on the survival or the success rate. The marginal bone level remained stable with only minimal loss of 0.3 mm after 60 months of loading. Conclusions: Within the limitations of this study, immediate loading is feasible for dental implants in edentulous jaws.

Real-time path replanning in dynamic environments (동적 환경에서의 실시간 경로 설정 방법)

  • Kwak, Jae-Hyuk;Lim, Joon-Hong
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.43 no.6 s.312
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    • pp.1-8
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    • 2006
  • Many researches on path planning and obstacle avoidance for the fundamentals of mobile robot have been done recently. Informations from various sensors can be used to find obstacles and plan feasible path. In spite of many solutions of finding optimal path, each can be applied in only a constrained condition. This means that it is difficult to find university good algorithm. An optimal path with a complicated computation generates a time delay which cannot avoid moving obstacles. In this paper, we propose an algorithm of path planning and obstacle avoidance for mobile robot. We call the proposed method Random Access Sequence(RAS) method. In the proposed method, a small region is set first and numbers are assigned to its neighbors, then the path is selected using these numbers and cumulative numbers. It has an advantage of fast planning time and completeness of path if one exists. This means that new path selection may be possible within short time and that helps a robot to avoid obstacle in dynamic environments. Using the information of the start and destination position, the RAS can be performed for collision-free navigation by reforming feasible paths repeatedly in dynamic environments.

AN EXPERIMENTAL STUDY FOR ESTABLISHMENT OF ORTHOTOPIC SALIVARY TUMOR MODELS IN MICE (마우스에서 타액선암 동위종양 모델 제작을 위한 실험적 연구)

  • Park, Young-Wook;Chung, Seong-Hoon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.2
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    • pp.81-93
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    • 2007
  • Purpose: Adenoid cystic carcinoma (ACC) is a relatively rare tumor that arises in glandular tissues of the head and neck region and sometimes has a protracted clinical course with perineural invasion and delayed onset of distant lung metastasis. Treatment failure of salivary ACC is most often associated with perineural and hematogenous tumor spread. However, very little has been known about the cellular and molecular mechanisms of perineural invasion and hematogenous distant metastasis of parotid ACC. This study was designed to develop an orthotopic tumor model of parotid adenoid cystic carcinoma in athymic nude mice. Experimental Design: A melanoma cell line was injected into the parotid gland of athymic mice to determine whether such implantation was technically feasible. A parotid ACC cell line was then injected into the parotid gland or the subcutaneous tissue of athymic mice at various concentrations of tumor cells, and the mice were thereafter followed for development of tumor nodule. The tumors were examined histopathologically for perineural invasion or regional or distant lung metastasis. We used an oral squmous cell carcinoma cell line as control. Results: Implantation of tumor(melanoma) cell suspension into the parotid gland of nude mice was technically feasible and resulted in the formation of parotid tumors. A parotid ACC cell line, ACC3 showed no significantly higher tumorigenicity, but showed significantly higher lung metastatic potential in the parotid gland than in the subcutis. In contrast, mucosal squmous cell carcinoma cell line doesn’t show significantly higher lung metastatic potential in the parotid gland than in the subcutis. The ACC tumor established in the parotid gland seemed to demonstrate perineural invasion of facial nerve, needs further study. Conclusion: An orthotopic tumor model of salivary ACC in athymic nude mice was successfully developed that closely recapitulates the clinical situations of human salivary ACC. This model should facilitate the understanding of the cellular and molecular mechanisms of tumorigenisis and metastasis of salivary ACC and aid in the development of targeted molecular therapies of salivary ACC.

Robust Real-time Face Detection Scheme on Various illumination Conditions (다양한 조명 환경에 강인한 실시간 얼굴확인 기법)

  • Kim, Soo-Hyun;Han, Young-Joon;Cha, Hyung-Tai;Hahn, Hern-Soo
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.7
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    • pp.821-829
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    • 2004
  • A face recognition has been used for verifying and authorizing valid users, but its applications have been restricted according to lighting conditions. In order to minimizing the restricted conditions, this paper proposes a new algorithm of detecting the face from the input image obtained under the irregular lighting condition. First, the proposed algorithm extracts an edge difference image from the input image where a skin color and a face contour are disappeared due to the background color or the lighting direction. In the next step, it extracts a face region using the histogram of the edge difference image and the intensity information. Using the intensity information, the face region is divided into the horizontal regions with feasible facial features. The each of horizontal regions is classified as three groups with the facial features(including eye, nose, and mouth) and the facial features are extracted using empirical properties of the facial features. Only when the facial features satisfy their topological rules, the face region is considered as a face. It has been proved by the experiments that the proposed algorithm can detect faces even when the large portion of face contour is lost due to the inadequate lighting condition or the image background color is similar to the skin color.