• Title/Summary/Keyword: Function Representation

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Execution of a functional Logic language using the Dataflow Graph Representation (데이터플로우 그래프 표현 방식을 이용한 함수 논리 언어의 실행)

  • Kim, Yong-Jun;Cheon, Suh-Hyun
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.9
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    • pp.2435-2446
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    • 1998
  • In this paper. We describe a dataflow model for efficient execution of a functional logic language and a method of translation a functional logic language into a dataflow graph. To explore parallelism and intelligent backtracking, we us model in which clause and function are represented as independent dataflow graph. The node denotes basic actions to be performed when the clause and function are executed. The dataflow mechanism allows an operation to be executed as soon as all its operands are available. Since the operations can never be executed earlier, a dataflow model is an excellent base for increasing execution speed. We did decrease a delay time with concurrent execution of dependency analysis and subgoal.

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Accurate Representation of Light-intensity Information by the Neural Activities of Independently Firing Retinal Ganglion Cells

  • Ryu, Sang-Baek;Ye, Jang-Hee;Kim, Chi-Hyun;Goo, Yong-Sook;Kim, Kyung-Hwan
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.3
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    • pp.221-227
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    • 2009
  • For successful restoration of visual function by a visual neural prosthesis such as retinal implant, electrical stimulation should evoke neural responses so that the informat.ion on visual input is properly represented. A stimulation strategy, which means a method for generating stimulation waveforms based on visual input, should be developed for this purpose. We proposed to use the decoding of visual input from retinal ganglion cell (RGC) responses for the evaluation of stimulus encoding strategy. This is based on the assumption that reliable encoding of visual information in RGC responses is required to enable successful visual perception. The main purpose of this study was to determine the influence of inter-dependence among stimulated RGCs activities on decoding accuracy. Light intensity variations were decoded from multiunit RGC spike trains using an optimal linear filter. More accurate decoding was possible when different types of RGCs were used together as input. Decoding accuracy was enhanced with independently firing RGCs compared to synchronously firing RGCs. This implies that stimulation of independently-firing RGCs and RGCs of different types may be beneficial for visual function restoration by retinal prosthesis.

Use of the surface-based registration function of computer-aided design/computer-aided manufacturing software in medical simulation software for three-dimensional simulation of orthognathic surgery

  • Kang, Sang-Hoon;Lee, Jae-Won;Kim, Moon-Key
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.39 no.4
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    • pp.197-199
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    • 2013
  • Three-dimensional (3D) computed tomography image models are helpful in reproducing the maxillofacial area; however, they do not necessarily provide an accurate representation of dental occlusion and the state of the teeth. Recent efforts have focused on improvement of dental imaging by replacement of computed tomography with other detailed digital images. Unfortunately, despite the advantages of medical simulation software in dentofacial analysis, diagnosis, and surgical simulation, it lacks adequate registration tools. Following up on our previous report on orthognathic simulation surgery using computer-aided design/computer-aided manufacturing (CAD/CAM) software, we recently used the registration functions of a CAD/CAM platform in conjunction with surgical simulation software. Therefore, we would like to introduce a new technique, which involves use of the registration functions of CAD/CAM software followed by transfer of the images into medical simulation software. This technique may be applicable when using various registration function tools from different software platforms.

A Study on the Optimum Thickness Distributions of Plate Structures with Different Essential Boundary Conditions (경계조건에 따른 판 구조물의 최적두께분포에 대한 연구)

  • Lee, Sang-Jin;Kim, Ha-Ryong
    • Journal of Korean Association for Spatial Structures
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    • v.5 no.4 s.18
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    • pp.53-59
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    • 2005
  • This paper provides the results of the investigation on the optimum thickness distribution of plate structures with different essential boundary conditions. In this study, the strain energy to be minimized is considered as the objective function and the initial volume of structures is used as the constraint function. The computer-aided geometric design (CAGD) such as Coon's patch representation is used to represent the thickness distribution of plates. A reliable degenerated shell finite element is adopted to calculate the accurate strain energy level of the plates. Robust optimization algorithms provided in the optimizer DOT are adopted to search the optimum thickness values during the optimization iteration. Finally, the square plate is used to find out the optimum thickness distribution of plates according to different essential boundary condition.

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A Study on Deconstructured Space and Visibility in Clothes - Regarding Hussein Chalayan′s Design- (의복에서의 탈구조적 공간과 가시성에 대한 연구 -후세인 칼라얀의 디자인을 중심으로-)

  • 김혜영
    • Journal of the Korean Society of Costume
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    • v.50 no.4
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    • pp.5-20
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    • 2000
  • Through his geometric design, the Cyprus born fashion designer Hussein Chalayan raises intriguing questions about the very fact of wearing clothes. By purposefully displacing the function of each part of the clothing, such as neck line, hem line, seam, sleeve, etc., Chalayan transforms the meaning of the body that wears clothes. of the human subject as a sovereign possessor of the clothing and the visibility related to fashion. This transformation is achieved by distorting the spaces of his clothing in an unorthodox way. This thesis argues that the significance of such a practice can not be properly understood without relation to the current debate on deconstructionism under way in humanities. Instead of immediately negating the modern frame of Ideas and practices, deconstructionism asks what the assumptions for the modern regime of truth is. In this process, things that lead human beings to sovereign master of knowledge and truth such as reason, subject, body and vision are questioned. In the same context, Chalayan's design not only forces us to rethink the very function of dividing inside and outside by the clothing but also the meaning of boundary operating in numerous sites of modern life. As the human subject is not something pre-given but constructed according to the cultural representation, to which the clothing belongs, fashion can be evaluated to be an active ingredient of constructing the subject. Therefore, Hussein Chalayan's design is at the cross road between the modern and the postmodern regime of fashion.

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Design of Robust Load Frequency Controller using Mixed Sensitivity based $H_{\infty}$ norm (혼합강도 $H_{\infty}$ 제어기법을 이용한 강인한 부하주파수 제어기 설계)

  • 정형환;김상효;이정필;한길만
    • Journal of Advanced Marine Engineering and Technology
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    • v.24 no.3
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    • pp.88-98
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    • 2000
  • In this paper, a robust controller using $H_{\infty}$ control theory has been designed for the load frequency control of interconnected 2-area power system. The main advantage of the proposed $H_{\infty}$ controller is that uncertainties of power system can be included at the stage of controller design. Representation of uncertainties is modeled by multiplicative uncertainly. In the mixed sensitivity problems, disturbance attenuation and uncertainty of the system is treated simultaneously. The robust stability and the performance of model uncertainties are represented by frequency weighted transfer function. The design of load frequency controller for each area was based on state-space approach. The comparative computer simulation results for the proposed controller and the conventional techniques such as the optimal control and the PID one were analyzed at the additions of various disturbances. Their deviation magnitude of frequency and tie line power flow at each area were mainly evaluated. Also the testing results of robustness for the cases that the perturbations of the all parameters of power system were amounted to about 20% were introduced. It was approved that the resultant performances of the proposed $H_{\infty}$ controller with mixed sensitivity were more robust and stable than the one of conventional controllers.

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Implementation of an Efficient Service Discovery Protocol for Directory Facilitator Based on CALM Agent (CLAM 에이전트 기반 Directory Facilitator를 위한 효율적인 서비스 디스커버리 프로토콜 구현)

  • Lee, Seung-Hyun;Shin, Dong-Ryeol;Jang, Kyung-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.6
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    • pp.275-282
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    • 2011
  • Current service discovery protocols such as UPnP, Jini, SLP provide the basic function which is message exchange pattern, service representation and description, in service discovery. They does not guarantee service interoperability among service discovery. Therefore, in this paper, we design and implement CLAM (Component-based Autonomic Layered Middleware) agent platform to enable an efficient service discovery through extension of DF agent function in FIPA-compliant specification. Also, we propose an efficient service discovery mechanism using DHT-Chord algorithm to guarantee scalability and interoperability in DF agent.

Identification of Volterra Kernels of Nonlinear System Having Backlash Type Nonlinearity

  • Rong, Li;Kashiwagi, H.;Harada, H.
    • 제어로봇시스템학회:학술대회논문집
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    • 1999.10a
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    • pp.141-144
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    • 1999
  • The authors have recently developed a new method for identification of Volterra kernels of nonlinear systems by use of pseudorandom M-sequence and correlation technique. And it is shown that nonlinear systems which can be expressed by Volterra series expansion are well identified by use of this method. However, there exist many nonlinear systems which can not be expressed by Volterra series mathematically. A nonlinear system having backlash type nonliear element is one of those systems, since backlash type nonlinear element has multi-valued function between its input and output. Since Volterra kernel expression of nonlinear system is one of the most useful representations of non-linear dynamical systems, it is of interest how the method of Volterra kernel identification can be ar plied to such backlash type nonlinear system. The authors have investigated the effect of application of Volterra kernel identification to those non-linear systems which, accurately speaking, is difficult to express by use of Volterra kernel expression. A pseudorandom M-sequence is applied to a nonlinear backlash-type system, and the crosscorrelation function is measured and Volterra kernels are obtained. The comparison of actual output and the estimated output by use of measured Volterra kernels show that we can still use Volterra kernel representation for those backlash-type nonlinear systems.

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Expertise Effects in Situation Awareness Sensitivity : Information Processing Approach (상황인식 민감도에 있어서의 전문성 효과 : 정보처리 접근법)

  • ;Andrew R. Dattel
    • Science of Emotion and Sensibility
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    • v.5 no.1
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    • pp.79-90
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    • 2002
  • The role of memory is viewed as central to developing and maintaining flight situation awareness (SA). The present research examines constituent memory processes that underlie flight SA sensitivity as a function of pilot expertise. In Experiment 1, pilot memory for different forms (spatial or verbal) of cockpit situational information was tested immediately after presentation of the information (immediate recall) or after 30-s delay filled with an intervening task (delayed recall). In Experiment 2, pilot SA sensitivity was examined and correlated with memory measures obtained in Experiment 1. Results suggest that an expertise effect occurs in delayed recall but not in immediate recall and that memory representation of situational information required to develop high levels of SA sensitivity varies as a function of expertise. Theoretical accounts of results are discussed in the context of psychological theories of expertise.

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De Bruijn Sequence Generation Based on D-Homomorphism (D-준동형사상을 바탕으로 한 드브루인 수열 만들기)

  • Song, Iick-Ho;Park, So-Ryoung;Yoon, Seok-Ho;Kim, Hong-Gil
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.6
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    • pp.9-16
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    • 1999
  • In this paper, an efficient algorithm for generation do Lempel's D-homomorphism. This number of exclusive-or operations required to generate the next bit for de Bruijn sequences of order n from a de Bruijm function of order k is shown to be approximately $k(2^{W(n-k)}-1)$where W(r) is the number of one's in the binary representation of r: therefore, the number of required operations can reduced to k if the de Bruijn function is selected appropriately.

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