• 제목/요약/키워드: IS1081

검색결과 204건 처리시간 0.021초

공압형 인공근육을 이용한 상극구동의 동적 특성 (Dynamic Characteristics of an Antagonistic Actuation with Pneumatic Artificial Muscles)

  • 강봉수;송승
    • 대한기계학회논문집A
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    • 제33권10호
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    • pp.1081-1086
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    • 2009
  • This paper presents dynamic characteristics of pneumatic artificial muscles. Since the actuating performance of a pneumatic muscle is closely related to the input pressure of a pneumatic muscle, the air flow model on a valve orifice and an elastic bladder of the muscle is formulated to estimate precisely the pressure variance of pneumatic muscles during deflating and inflating process. Frequency response experiments are performed with an antagonistic system consisting of two pneumatic muscles and fast pneumatic control valves. Comparing with experimental results, the proposed model yielded good performance in estimating dynamic motions of the antagonistic system as well as the pressure variance of the pneumatic artificial muscles

Taylor Vortex의 구조에 대한 연구 (On the Structures of Taylor Vortices.)

  • 황종연;양경수
    • 대한기계학회논문집B
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    • 제27권8호
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    • pp.1081-1088
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    • 2003
  • Numerical investigation on the structures of various Taylor vortices induced in the flow between two concentric cylinders, with the inner one rotating and with a pressure-driven axial flow imposed, is carried out, and compared with the experiments of Wereley and Lueptow [Phys. fluid, 11(12), 1999] who studied the Taylor vortices using PIV in detail. Especially, the properties of helical vortices and random wavy vortices are discussed, and their three-dimensional structures are visualized using the numerical data. Our simulation also predicts that random wavy vortices have quasi-periodic movement which can be explained by traveling waves formed in the azimuthal direction. The numerical results are well consistent with the experimental findings of Wereley and Lueptow.

Two Dimensional Electronic Spectroscopy

  • Fleming, Graham R.;Yang, Min-O;Agarwal, Ritesh;Prall, Bradley S.;Kaufman, Laura J.;Neuwahl, Fred
    • Bulletin of the Korean Chemical Society
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    • 제24권8호
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    • pp.1081-1090
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    • 2003
  • Two different electronically resonant two-dimensional spectroscopies are described. The first, two-color photon echo peak shift spectroscopy, is sensitive to correlations in transition frequency between the initial and probed (final) states. It provides new insight into the mechanism of ultrafast solvation and should prove useful for characterizing dynamics in inhomogeneous systems in general. The second technique, fifth order threepulse scattering, contains two coherence periods whose durations are controlled. The entire two-dimensional surface was recorded for a dye molecule in dilute solution and a photosynthetic light-harvesting complex. The data provide insight into the short-time dynamics of solvation and exciton relaxation, respectively.

Study of Commercial Business Men and Employers' Recognition on the Existence Effect of the Roadside Trees

  • Kim Bum-Soo;Oh Jeong-Soo
    • 한국환경과학회지
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    • 제14권12호
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    • pp.1081-1085
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    • 2005
  • This study is carried out for obtaining the basic materials for presentation of creation and desirable management of urban roadside trees through analyse the existence effect of trees on people who operate th commercial areas along the streets. Roadside tree and green areas are recognized comfort space in addition to simple planting area. Therefore various trees and flowering plants should be introduced in addition to roadside facilities for convenience. Planted roadside trees should be maintained. We will propose an method that residents plant and manage the trees and flowering plants on the two lane of one way road. However main lines more than four lane of one way have more public property beside the residents space. Therefore these should be maintained mainly by related government agencies.

파이버 브래그 격자를 이용한 곡률 측정 (Curvature Measurement Using Fiber Bragg Gratings)

  • 정진호;이종윤
    • 한국산학기술학회논문지
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    • 제9권4호
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    • pp.1081-1085
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    • 2008
  • 본 논문에서는 곡률을 측정하기 위해 파이버 브래그 격자를 이용한 곡률 센서에 대해 연구하고자 한다. 곡률의 변화를 측정하기 위해 브래그 공진파장의 이동 변화를 측정하였다. 실험견과로부터 곡률이 $0\;m^{-1}$에서 $10\;m^{-1}$까지 증가함에 따라 반사 스펙트럼은 감소하나. 브래그 공진 파장의 변화량은 선형적으로 증가함을 알 수 있었으며, 기울기는 대략 $8.8\;pm/m^{-1}$ 이었다. 한편, 반사 스펙트럼은 곡률이 증가함에 따라 감소하였다.

MOM 서비스에 의한 HLA 페더레이션 연동 성능 분석 (Performance Analysis of Interoperated HLA Federations for MOM Service)

  • 유민욱;김탁곤
    • 한국군사과학기술학회지
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    • 제14권6호
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    • pp.1081-1090
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    • 2011
  • High Level Architecture(HLA) is a specification for interoperation among heterogeneous simulators which are executed in a distributed environment. HLA originally allows a number of federates to join in a federation using a single RTI(Run-Time Infrastructure). To interoperate federations without modifying RTI, agent federate, which represents behavior of a federation, can be used. Agent federate can use MOM(Management Object Model) service or agent-user protocol to acquire information of a federation. This paper performs various experiments to measure performance of two architectures. MOM service shows a loss of performance but can be applied without modifying user federates. Experiment results can be used to determine appropriate architecture for interoperation of federations.

VIBRATIONAL SPECTROSCOPY IN INDUSTRIAL CHEMICAL QUALITY CONTROL

  • Siesler, H.W.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1081-1081
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    • 2001
  • The constant need for quality improvement and production rationalization in the chemical and related industries has led to the increasing replacement of conservative control procedures by more specific and environmentally compatible analytical techniques. In this respect, vibrational spectroscopy has developed over the last yews - in combination with new instrumental accessories and statistical evaluation procedures - to one of the most important analytical tools for industrial chemical quality control and process monitoring in a wide field of applications. In the present communication this potential is demonstrated in order to further support the implementation of mid-infrared (MIR), near-infrared (NIR) and Raman spectroscopy Primarily as industrial on-line tools. To this end the data of selected feasibility studies will be discussed in terms of the individual strengths of the different techniques for the respective application.

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폐에 발생한 경화성 혈관종 (Sclerosing Hemangioma of the Lung - A case report -)

  • 조은희
    • Journal of Chest Surgery
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    • 제25권10호
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    • pp.1076-1081
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    • 1992
  • The sclerosing hemangioma of the lung is rare, benign neoplasms, which are usually solitary, Althoughh their histologic apperances are distinct and well-defined, their histogenesis is uncertain. We experienced a typical lesion of pulmonary sclerosing hemangioma clinically and histologically, which was removed from the right lobe of 64-year-old female. We disccused histogenesis, microscopic feature and progress of the sclerosing hemangioma.

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Feedforward actuator controller development using the backward-difference method for real-time hybrid simulation

  • Phillips, Brian M.;Takada, Shuta;Spencer, B.F. Jr.;Fujino, Yozo
    • Smart Structures and Systems
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    • 제14권6호
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    • pp.1081-1103
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    • 2014
  • Real-time hybrid simulation (RTHS) has emerged as an important tool for testing large and complex structures with a focus on rate-dependent specimen behavior. Due to the real-time constraints, accurate dynamic control of servo-hydraulic actuators is required. These actuators are necessary to realize the desired displacements of the specimen, however they introduce unwanted dynamics into the RTHS loop. Model-based actuator control strategies are based on linearized models of the servo-hydraulic system, where the controller is taken as the model inverse to effectively cancel out the servo-hydraulic dynamics (i.e., model-based feedforward control). An accurate model of a servo-hydraulic system generally contains more poles than zeros, leading to an improper inverse (i.e., more zeros than poles). Rather than introduce additional poles to create a proper inverse controller, the higher order derivatives necessary for implementing the improper inverse can be calculated from available information. The backward-difference method is proposed as an alternative to discretize an improper continuous time model for use as a feedforward controller in RTHS. This method is flexible in that derivatives of any order can be explicitly calculated such that controllers can be developed for models of any order. Using model-based feedforward control with the backward-difference method, accurate actuator control and stable RTHS are demonstrated using a nine-story steel building model implemented with an MR damper.

Robotic Surgery in Cancer Care: Opportunities and Challenges

  • Mohammadzadeh, Niloofar;Safdari, Reza
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권3호
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    • pp.1081-1083
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    • 2014
  • Malignancy-associated mortality, decreased productivity, and spiritual, social and physical burden in cancer patients and their families impose heavy costs on communities. Therefore cancer prevention, early detection, rapid diagnosis and timely treatment are very important. Use of modern methods based on information technology in cancer can improve patient survival and increase patient and health care provider satisfaction. Robot technology is used in different areas of health care and applications in surgery have emerged affecting the cancer treatment domain. Computerized and robotic devices can offer enhanced dexterity by tremor abolition, motion scaling, high quality 3D vision for surgeons and decreased blood loss, significant reduction in narcotic use, and reduced hospital stay for patients. However, there are many challenges like lack of surgical community support, large size, high costs and absence of tactile and haptic feedback. A comprehensive view to identify all factors in different aspects such as technical, legal and ethical items that prevent robotic surgery adoption is thus very necessary. Also evidence must be presented to surgeons to achieve appropriate support from physicians. The aim of this review article is to survey applications, opportunities and barriers to this advanced technology in patients and surgeons as an approach to improve cancer care.