• 제목/요약/키워드: new approaches

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시스템이론 기반의 안전사고 모델의 해석과 응용사례 소개 (An Introduction to Systems Theory Approach to Accident Modeling AND Its Applications)

  • 박철호;박영원
    • 시스템엔지니어링워크숍
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    • 통권4호
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    • pp.151-154
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    • 2004
  • This paper presents the general system theory and its applications to the safety analysis method that is a recent trend over the traditional event-driven model. This new model is known as STAMP(Systems Theory Accident Modeling and Process)proposed by Nancy G. Leveson in MIT. The new model has benefits of systemic approaches concerning the system safety as a whole including the context it is in, its stimulants and outcomes, and its parts as well as the relationships among them in a holistic manner. The method consists of a hierarchical control structure, a process model, and the safety constraints governing the control. This paper demonstrates an example the contrasts the differences between the approaches of STAMP and the traditional safety models.

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완화된 Non-Quadratic 안정화 조건을 기반으로 한 이산 시간 Takagi-Sugeno 퍼지 시스템의 최적 제어 (Optimal Control for Discrete-Time Takagi-Sugeno Fuzzy Systems Based on Relaxed Non-Quadratic Stabilization Conditions)

  • 이동환;박진배;양한진;주영훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1724_1725
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    • 2009
  • In this paper, new approaches to optimal controller design for a class of discrete-time Takagi-Sugeno (T-S) fuzzy systems are proposed based on a relaxed approach, in which non-quadratic Lyapunov function and non-parallel distributed compensation (PDC) control law are used. New relaxed conditions and linear matrix inequality (LMI) based design methods are proposed that allow outperforming previous results found in the literature. Finally, an example is given to demonstrate the efficiency of the proposed approaches.

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다물체계의 자려진동 구현을 위한 마찰 모델링 (Friction Model to Realize Self-Excited Vibration of Multi-body Systems)

  • 노현영;유홍희
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 춘계학술대회논문집
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    • pp.103-108
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    • 2007
  • This paper presents a friction model to realize self-excited vibration of multi-body systems. The friction coefficient is modeled with a spline function in most commercial codes. Even if such a function resolves the problem of discontinuity in friction force, it cannot realize self-excited vibration phenomena. Furthermore, as the relative velocity approaches zero, the friction coefficient approaches zero with the conventional model. So, slip occurs when small force is applied to the system. To avoid these problems a new friction model is proposed in this study. With the new friction model, the self-excited vibration can be realized since the friction coefficient changes with the relative velocity. Furthermore, the slip phenomena could be reduced significantly with the proposed model.

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초저황 디젤 생산을 위한 탈황 기술 동향 (Review of Desulfurization Technology for Ultra Low Sulfur Diesel Production)

  • 박조용;김재곤;임의순;정충섭
    • 한국응용과학기술학회지
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    • 제30권3호
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    • pp.431-443
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    • 2013
  • Sulfur content of diesel fuel has been cut down to under 10 ppm ULSD (ultra low sulfur diesel) level by environmental regulation with the aim of reducing exhaust emissions. This review discusses the methods and principles of sulfur reduction in diesel and presents an overview of new approaches for ultra-deep desulfurization. The deep HDS (hydrodesulfurization) problems of diesel streams is exacerbated by the inhibiting effect of co-existing aromatics, nitrogen compounds and $H_2S$. The new approaches to deep desulfurization includes non-HDS type processing schemes such as adsorptive, extractive and oxidative desulfurization.

종양 표적 유전자 치료 (Tumor targeted gene therapy)

  • 강주현
    • Nuclear Medicine and Molecular Imaging
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    • 제40권5호
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    • pp.237-242
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    • 2006
  • Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy based on the transfer of genetic material to an organism with the aim of correcting a disease. The application of gene therapy to the cancer treatment has led to the development of new experimental approaches such as suicidal gene therapy, inhibition of oncogenes and restoration of tumor-suppressor genes. Suicidal gene therapy is based on the expression in tumor cells of a gene encoding an enzyme that converts a prodrug into a toxic product. Representative suicidal genes are Herpes simplex virus type 1 thymidine kinase (HSV1-tk) and cytosine deaminase (CD). Especially, physicians and scientists of nuclear medicine field take an interest In suicidal gene therapy because they can monitor the location and magnitude, and duration of expression of HSV1-tk and CD by PET scanner.

2차 통계값과 절대평균을 이용한 비최소 위상 FIR 시스템의 미상 식별 (Blind identification of nonminimum phase FIR systems from second-order statistics and absolute mean)

  • 박양수;박강민;송익호;김형명
    • 한국통신학회논문지
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    • 제21권2호
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    • pp.357-364
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    • 1996
  • 이 논문에서는 고차통계값을 쓰지 않고 비최소 위상 FIR 시스템을 미상 식별(blind identification)할 수 있는 새로운 방법을 제안한다. 제안하는 방법은 2차 백색 신호의 절대평균으로 그 신호의 고차 백색성 여부를 판단할 수 있다는 관찰에서 얻어진다. 제안한 방법은 고차통계값을 쓰는 방법의 새로운 대안이 될 수 있다. 컴퓨터 모의실험을 통해서, 절대평균이 정확히 추정됨을 알 수 있었고 제안한 방법이 고차통계값을 쓰는 방법의 여러 단점을 해결할 수 있음을 보였다.

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시스템 이론 기반의 안전사고 모델의 해석과 응용사례 소개 (An Introduction to Systems Theory Approach to Accident Modeling and Its Applications)

  • 박철호;박영원
    • 시스템엔지니어링학술지
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    • 제1권1호
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    • pp.20-25
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    • 2005
  • This paper presents the general system theory and its applications to the safety analysis method that is a recent trend over the traditional event-driven model. This new model is known as STAMP(Systems Theory Accident Modeling and Process) proposed by Nancy G. Leveson in MIT. The new model has benefits o f systemic approaches concerning the system safety as a whole including the context it is in, its stimulants and outcomes, and its parts as well as the relationships among them in a holistic manner. The method consists of a hierarchical control structure, a process model, and the safety constraints governing the control. This paper demonstrates an example that contrasts the differences between the approaches of STAMP and the traditional safety models.

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The Use of MSVM and HMM for Sentence Alignment

  • Fattah, Mohamed Abdel
    • Journal of Information Processing Systems
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    • 제8권2호
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    • pp.301-314
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    • 2012
  • In this paper, two new approaches to align English-Arabic sentences in bilingual parallel corpora based on the Multi-Class Support Vector Machine (MSVM) and the Hidden Markov Model (HMM) classifiers are presented. A feature vector is extracted from the text pair that is under consideration. This vector contains text features such as length, punctuation score, and cognate score values. A set of manually prepared training data was assigned to train the Multi-Class Support Vector Machine and Hidden Markov Model. Another set of data was used for testing. The results of the MSVM and HMM outperform the results of the length based approach. Moreover these new approaches are valid for any language pairs and are quite flexible since the feature vector may contain less, more, or different features, such as a lexical matching feature and Hanzi characters in Japanese-Chinese texts, than the ones used in the current research.

Novel computational approaches characterizing knee physiotherapy

  • Kim, Wangdo;Veloso, Antonio P.;Araujo, Duarte;Kohles, Sean S.
    • Journal of Computational Design and Engineering
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    • 제1권1호
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    • pp.55-66
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    • 2014
  • A knee joint's longevity depends on the proper integration of structural components in an axial alignment. If just one of the components is abnormally off-axis, the biomechanical system fails, resulting in arthritis. The complexity of various failures in the knee joint has led orthopedic surgeons to select total knee replacement as a primary treatment. In many cases, this means sacrificing much of an other-wise normal joint. Here, we review novel computational approaches to describe knee physiotherapy by introducing a new dimension of foot loading to the knee axis alignment producing an improved functional status of the patient. New physiotherapeutic applications are then possible by aligning foot loading with the functional axis of the knee joint during the treatment of patients with osteoarthritis.

Design Parameters of Polymers for Tissue Engineering Applications

  • Lee, Kuen-Yong
    • Macromolecular Research
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    • 제13권4호
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    • pp.277-284
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    • 2005
  • The loss or failure of an organ or tissue can occur because of accident or disease, for which tissue or organ transplantation is a generally accepted treatment. However, this approach is extremely limited due to donor shortage. Tissue engineering is a new and exciting strategy, in which patients who need a new organ or tissue are supplied with a synthetic organ or tissue. In this approach, tissues are engineered using a combination of the patient's own cells and a polymer scaffold. The polymer scaffold potentially mimics many roles of extracellular matrices in the body. Various polymers have been studied and utilized to date in tissue engineering approaches. However, no single polymer has been considered ideal for all types of tissues and approaches. This paper discusses the design parameters of those polymers potentially useful in tissue regeneration.