• Title/Summary/Keyword: the Information Poor

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The Content Structure of the Navigation Course Using Learning Hierarchy (학습위계에 의한 항해교과의 내용 구조화)

  • Yoon, Hyun-Sang
    • Journal of Fisheries and Marine Sciences Education
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    • v.6 no.2
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    • pp.198-216
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    • 1994
  • The problem of promoting instructional effect using reorganizing the content of textbook is one of the major concerns of many education theorists and teachers. The results of many researches about above problem reveal that reorganizing the content of textbook promotes the ability of recall and problem solving of learners. The content structure of current navigation textbook revealed a categorical structure as its basic framework, though it seems to be a poor one. A categorical structure is known as providing an inferior information processing mechanism for learners than a learning hierarchy content structure is. Furthermore current content structure hasn't given any considerations to navigation in practice, spatial contexts and sequential events of ships from a harbor to another harbor. The learning hierarchy content structure has an advantage of giving learners more systematic and stronger knowledge networks than a categorical structure.

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A Theoretical Study and Implementation of Spinal Traction System (척추견인 시스템의 인체 역학적 견인력에 대한 이론적 고찰 및 구현에 관한 연구)

  • Chang, Hojong;Lee, Song Jae
    • Journal of Biomedical Engineering Research
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    • v.35 no.2
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    • pp.19-25
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    • 2014
  • According to recent data more than 80% of people suffer from back pain, due to an aging and a poor posture, at least once in their life time, and 7~10% of them have chronic spine illness. Researchers over the years have studied on various spinal traction devices that utilize the force of traction, and have also reported clinical test results. However, most existing devices are too complicated and too expensive. In order to solve these problems, we have developed a new device in which the frame moves up and down and at the same time tilting angle of the frame is adjusted. We have analyzed the forces applied on the body as a function of tilting angle. And the result shows that the new device has achieved the force of traction, which is known to be effective for spinal rehabilitation.

Effect of Slip System Transition on the Deformation Behavior of Mg-Al Alloy: Internal Variable Based Approach (비탄성 변형 이론을 바탕으로 한 Mg-Al 합금의 슬립기구 천이 현상 해석)

  • Lee H.S.;Chang Y. W.;Bang W.
    • Transactions of Materials Processing
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    • v.13 no.6 s.70
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    • pp.535-539
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    • 2004
  • Although magnesium has high potential for structural material due to the lightweight and high specific strength, the structural application has been limited by the low ductility at room temperature. The reason of the poor ductility is few activated slip systems of magnesium (HCP structure) during deformation. As temperature increases, however, additional non-basal slip systems are incorporated to exhibit higher ductility comparable to aluminum. In the present study, a series of tensile tests of Mg-Al alloy has been carried out to study deformation behavior with temperature variation. Analysis of load relaxation test results based on internal variable approach gave information about relationship between the micromechanical character and corresponding deformation behavior of magnesium. Especially, the material parameter, p representing dislocation permeability through barriers was altered from 0.1 to 0.15 as the non-basal slip systems were activated at high temperature.

Usefulness of Multiphase Scaffolds for Improving Tendon to Bone Healing for Rotator Cuff Tears in Shoulder (회전근개파열에서 힘줄뼈부착부 개선을 위한 다상 스캐폴드의 유용성)

  • Lee, Sang Chul
    • Clinical Pain
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    • v.19 no.2
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    • pp.59-63
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    • 2020
  • Rotator cuff tear is often cited as a reason for shoulder pain and dysfunction in patients > 40 years of age. Surgical repair of rotator cuff tear is one of the most commonly performed orthopedic surgical procedures. Until now, the success rate of surgical repair for rotator cuff tear has not been satisfactory. Many factors influence the process of rotator cuff repair such as the presence of tendinosis and fatty infiltration, but the main factor is the difficulty in achieving healing at the tendon to bone interface. There is a clinical need for bioengineering approaches to promote regeneration of the native enthesis and reduce the poor outcomes after surgical repair. Toward this end, the design and fabrication of multiphasic or hierarchically structured scaffolds have received great attention. This manuscript deals with information on the tendon to bone interface and tries to find out why a multiphasic scaffold is necessary to reproduce it and considerations that need to be taken into to make an ideal scaffold.

A Study on Adaptive Random Signal-Based Learning Employing Genetic Algorithms and Simulated Annealing (유전 알고리즘과 시뮬레이티드 어닐링이 적용된 적응 랜덤 신호 기반 학습에 관한 연구)

  • Han, Chang-Wook;Park, Jung-Il
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.10
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    • pp.819-826
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    • 2001
  • Genetic algorithms are becoming more popular because of their relative simplicity and robustness. Genetic algorithms are global search techniques for nonlinear optimization. However, traditional genetic algorithms, though robust, are generally not the most successful optimization algorithm on any particular domain because they are poor at hill-climbing, whereas simulated annealing has the ability of probabilistic hill-climbing. Therefore, hybridizing a genetic algorithm with other algorithms can produce better performance than using the genetic algorithm or other algorithms independently. In this paper, we propose an efficient hybrid optimization algorithm named the adaptive random signal-based learning. Random signal-based learning is similar to the reinforcement learning of neural networks. This paper describes the application of genetic algorithms and simulated annealing to a random signal-based learning in order to generate the parameters and reinforcement signal of the random signal-based learning, respectively. The validity of the proposed algorithm is confirmed by applying it to two different examples.

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Stereotactic radiotherapy for early stage non-small cell lung cancer

  • Ricardi, Umberto;Badellino, Serena;Filippi, Andrea Riccardo
    • Radiation Oncology Journal
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    • v.33 no.2
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    • pp.57-65
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    • 2015
  • Stereotactic body radiotherapy (SBRT) represents a consolidated treatment option for patients with medically inoperable early stage non-small cell lung cancer (NSCLC). The clinical evidence accumulated in the past decade supports its use as an alternative to surgery with comparable survival outcomes. Due to its limited toxicity, SBRT is also applicable to elderly patients with very poor baseline pulmonary function or other severe comorbidities. Recent comparative studies in operable patients raised the issue of the possible use of SBRT also for this subgroup, with quite promising results that still should be fully confirmed by prospective trials with long-term follow-up. Aim of this review is to summarize and discuss the major studies conducted over the years on SBRT and to provide data on the efficacy and toxicity of this radiotherapy technique for stage I NSCLC. Technical aspects and quality of life related issues are also discussed, with the goal to provide information on the current role and limitations of SBRT in clinical practice.

Earliest Virtual Deadline Zero Laxity Scheduling for Improved Responsiveness of Mobile GPUs

  • Choi, Seongrim;Cho, Suhwan;Park, Jonghyun;Nam, Byeong-Gyu
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.17 no.1
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    • pp.162-166
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    • 2017
  • Earliest virtual deadline zero laxity (EVDZL) algorithm is proposed for mobile GPU schedulers for its improved responsiveness. Responsiveness of user interface (UI) is one of the key factors in evaluating smart devices because of its significant impacts on user experiences. However, conventional GPU schedulers based on completely fair scheduling (CFS) shows a poor responsiveness due to its algorithmic complexity. In this letter, we present the EVDZL scheduler based on the conventional earliest deadline zero laxity (EDZL) algorithm by accommodating the virtual laxity concept into the scheduling. Experimental results show that the EVDZL scheduler improves the response time of the Android UI by 9.6% compared with the traditional CFS scheduler.

Energy-Efficient and High Performance CGRA-based Multi-Core Architecture

  • Kim, Yoonjin;Kim, Heesun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.3
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    • pp.284-299
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    • 2014
  • Coarse-grained reconfigurable architecture (CGRA)-based multi-core architecture aims at achieving high performance by kernel level parallelism (KLP). However, the existing CGRA-based multi-core architectures suffer from much energy and performance bottleneck when trying to exploit the KLP because of poor resource utilization caused by insufficient flexibility. In this work, we propose a new ring-based sharing fabric (RSF) to boost their flexibility level for the efficient resource utilization focusing on the kernel-stream type of the KLP. In addition, based on the RSF, we introduce a novel inter-CGRA reconfiguration technique for the efficient pipelining of kernel-stream on CGRA-based multi-core architectures. Experimental results show that the proposed approaches improve performance by up to 50.62 times and reduce energy by up to 50.16% when compared with the conventional CGRA-based multi-core architectures.

3-D position estimation for eye-in-hand robot vision

  • Jang, Won;Kim, Kyung-Jin;Chung, Myung-Jin;ZeungnamBien
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10b
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    • pp.832-836
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    • 1988
  • "Motion Stereo" is quite useful for visual guidance of the robot, but most range finding algorithms of motion stereo have suffered from poor accuracy due to the quantization noise and measurement error. In this paper, 3-D position estimation and refinement scheme is proposed, and its performance is discussed. The main concept of the approach is to consider the entire frame sequence at the same time rather than to consider the sequence as a pair of images. The experiments using real images have been performed under following conditions : hand-held camera, static object. The result demonstrate that the proposed nonlinear least-square estimation scheme provides reliable and fairly accurate 3-D position information for vision-based position control of robot. of robot.

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RPEM Algorithm for Adaptive Bilinear Filter (적응 쌍선형 필터의 RPEM 알고리즘)

  • 백흥기;황지원;안봉만
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.3
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    • pp.10-21
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    • 1993
  • Bilinear models are attractive for adaptive filtering applications because they can approximate a large class of nonlinear systems adequately, and usually with considerable parsimony in the number of coefficients compared with Volterra models. But bilinear filters have stability problem because they involve nonlinear feedback. Adaptive algorithms for bilinear filters may be diverge and have poor convergence characteristics when input signal is large In this paper, necessary and sufficient condition for mean square stability of bilinear filters for given input signal statistics is briefly described, and the method obtaining the input bound to guarantee the stability of bilinear filters is presented. New RPEM algorithm, which does not diverge and has the superior convergence characteristics compared with the conventional RPEM algorithm when input signal is large, is derived by applying the time-varying Kalman filtering concept to the conventional RPEM algorithm.

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