• Title/Summary/Keyword: Approach-Avoidance

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A Study on the Identification and Countermeasure of Singing Phenomenon in Ships (선박 명음(Singing) 현상의 규명과 대책에 관한 연구)

  • Joo, W.H.;Kim, D.H.;Bae, J.G.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.797-803
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    • 2000
  • Recently, the singing phenomenon was encountered during the sea trials of high speed catamaran and 46,000 TDW product carrier and remedied after various treatments, which were based on the reduction of vortex shedding strength and the avoidance of resonance, respectively. And, the numerical approach for structure-acoustical problem like singing phenomenon was established using MSC/NASTRAN and SYSNOISE. In this paper, the effectiveness of numerical approach was verified through the control of singing noise. And the results according to the modification were also discussed. Finally, the future works were described to enhance the numerical approach pattern for singing phenomenon.

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A New Approach to the Evaluation of Collision Risk using Sech Function (Sech 함수를 이용한 새로운 충돌위험도 평가법)

  • Jeong, Tae-Gweon
    • Journal of Navigation and Port Research
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    • v.27 no.2
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    • pp.103-109
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    • 2003
  • Evaluating the risk of collision quantitatively plays a key role in developing the expert system of navigation and collision avoidance. This study analysed the existing methods of appraising the collision risk, examined the problem that are intrinsic to them, and developed a new approach to its evaluation by using the sech function as an alternative to them. This paper applied the new method in appraising the collision risk and suggested how to decide the safe range of ownship's action.

Autonomous Wall-Following of Wheeled Mobile Robots using Hybrid Control Approach (차륜형 이동로봇의 자율 벽면-주행을 위한 하이브리드 제어)

  • Lim, Mee-Seub;Lim, Joon-Hong;Oh, Sang-Rok
    • Proceedings of the KIEE Conference
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    • 1999.07g
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    • pp.3105-3107
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    • 1999
  • In this paper, we propose a new approach to autonomous wall-following of wheeled mobile robots using hybrid control system. The hybrid control approach IS introduced to the motion control of nonholonomic mobile robots in the Indoor navigation problems. In hybrid control architecture, the discrete states are defined by the user-defined constraints, and the reference motion commands are specified In the abstracted motions. The hybrid control system applied to motion planning and autonomous navigation with obstacle avoidance In indoor navigation problem. Simulation results show that it is an effective method for the autonomous navigation in indoor environments.

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The Analysis of Relationships among Self-Handicapping Tendency, Goal Orientation, Self-Efficacy and Learning Strategies in Chemistry Education (화학교과에서 자아핸디캡경향, 목표지향성, 자기효능감 및 학습전략 사이의 관계분석)

  • Ko, Young-Chun
    • Journal of the Korean Chemical Society
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    • v.51 no.5
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    • pp.459-470
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    • 2007
  • The structural equation modeling techniques were used to assess a model of chemistry learning strategy based on self-handicapping tendency and goal orientation. Data were collected during chemistry lessons in two high schools. In the optimal model II-2 of this research, the self-handicapping tendency was negatively related to the use of self-efficacy. The learning goal was positively related to the use of self-efficacy and to learning strategy. The performance- approach goal was positively related to self-efficacy but presented an negative relationship to learning strategy. The performance-avoidance goal was negatively related to self-efficacy but presented an positive relationship to learning strategy. Besides affecting the learning strategy through self-efficacy indirectly, the learning goal, performance-approach goal, and performance-avoidance goal affected learning strategy directly. The self-handicapping tendency and performance- avoidance goal were a negative predictors of self-efficacy, but the learning goal and performance-approach goal were a positive predictors. And the self-efficacy affected learning strategy positively. The implications of these findings for learning strategy in chemistry are discussed. Although the paths model of relationships of the motivations to learn and learning strategies in chemistry education as mentioned above is established, the more systematic search for the higher self-efficacy and learning strategy in different courses and curriculums may be needed.

A Study of the Effects of Toddler's Temperament and Mother's Parenting Behavior on the Development of Vocabulary Ability (걸음마기 영아의 기질과 어머니의 양육행동이 영아의 어휘발달에 미치는 영향력에 관한 연구)

  • Kim, Ki Cheoul
    • Korean Journal of Childcare and Education
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    • v.12 no.1
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    • pp.1-17
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    • 2016
  • The objective of the study is to find out the effects of toddler's temperament and mother's parenting behavior on the development of vocabulary ability. The study was conducted with 299 infants between the ages of 18 and 24 months and their mothers in 47 day care centers in I city, Jeollabukdo. The results of the study are as follows. First, according to the correlation between infant's temperament and vocabulary based on the composition of temperament, approach-avoidance, adaptability, and mood showed a negative correlation with receptive and expressive vocabulary, and response intensity showed a positive correlation with receptive vocabulary. Second, according to the relation between mother's parenting behavior and infant's vocabulary ability based on the sub-factors of mother's parenting behavior, instructional parenting behavior and setting-limits parenting behavior showed a positive correlation with receptive and expressive vocabulary. Third, according to the effects of infant's temperament and mother's parenting behavior on the development of infant's vocabulary ability, as for the understanding of vocabulary, the explanation power of approach-avoidance is the highest, followed by instructional parenting behavior, response intensity, and mood. As for expressive vocabulary, the explanation power of instructional parenting behavior is the highest, followed by mood, response intensity and activity. In the development of infant's vocabulary ability, it was found that receptive vocabulary was affected the most by approach-avoidance, and expressive vocabulary was affected the most by instructional parenting behavior. Mothers will have to have interrelation skills suitable for temperament for the development of infant's receptive vocabulary, and have parenting behavior expressing the traits of things and events for the development of expressive vocabulary.

A Study on the Risk Evaluation in Two Dimensions at Sea with Even Risk Contour (등위험곡선을 이용한 해상의 2차원 위험도 평가에 관한 연구)

  • 공성호;이은방
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 1998.10b
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    • pp.1-9
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    • 1998
  • In the decision of a collision avoidance action for navigators and intellignet ships, it is necessary to evaluate the degree of surrounding risks effectively. We propose the new risk evaluation technique in two dimensions using Even Risk Contour on the basis of the concept of contour line. In this paper, we introduce the algorithms ofERC and Approach Velocity(AV) and show their application for avoiding traffic collision at sea.

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A simple and efficient planning of robot motions with obstacle avoidance (장애물이 있는 경우의 효율적인 로보트 동자계획)

  • 정봉주;이영훈
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1995.04a
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    • pp.880-885
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    • 1995
  • This paper deals with the efficient planning of robot motions in the Cartesian space while avoiding the collision with obstacles. The motion planning problem is to find a path from the specified starting robot configuration that avoids collision with a known set of stationary obstacles. A simple and efficient algorithm was developed using "Backward" approach to solve this problem. The computational result was satisfactory enough to real problems. problems.

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Research of Ideal Communication Methodology among Fault Tolerance System (결함 허용 시스템 간 이상적 통신방안 연구)

  • 구철회
    • Proceedings of the IEEK Conference
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    • 2003.07a
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    • pp.398-401
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    • 2003
  • In this paper, the basic concept and approach method of ideal communication among fault tolerance system has been studied and suggested. Fault tolerance should not be treated like Fault Avoidance and Fault Prevention. In this paper, Key specifications of mechanical and electrical characteristics of communication methods for fulfilling the requirements to meet the general purpose of fault tolerance system has been analyzed and presented.

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Collision Avoidances of an Autonomous Mobile Robot Hilt Unknown Obstacles (알려지지 않은 장애물 존재시 자율주행 운반체의 장애물 회피)

  • Won, Ji-Uk;Lee, Kee-Seong
    • Proceedings of the KIEE Conference
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    • 1994.11a
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    • pp.345-348
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    • 1994
  • A real-time collision avoidance algorithm for an AMR (Autonomous Mobile Robot) using the Distance Transform and Vector Field Histogram is studied. This approach enables AMR to find a collision-free path with the unknown obstacles. All system parameters including positions of the obstacles can be accepted using a mouse icon and all the obtained trajectories can be displayed on a computer monitor in graphics.

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Relationships of Achievement Goal Orientation with Academic Self-efficacy of Specialized High School Students (특성화고등학교 학생의 성취목표지향성과 학업적 자기효능감의 관계)

  • Yang, Jin-Sik;Song, Nak-Hyun;Lee, Chang-Hoon
    • 대한공업교육학회지
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    • v.43 no.2
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    • pp.79-96
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    • 2018
  • In this study, we look at the effect that the achievement goal of specialized high school students has on academic self-efficacy and the difference in academic self-efficacy depending on achievement goal orientation. The purpose of this research is to help students to efficiently increase their academic self-efficacy, develop research and study life guidance measures to improve negative factors, and select professors and learning methods. To achieve the purpose, survey was conducted with achievement goal orientation measurement tools(26 questions) and academic self-efficacy measurement tools(28 questions) for 745 students of 18 specialized technical high school students in 5 districts. The results of this study are as follows. First, preference to task difficulty and self-controlling efficacy have highly positive correlations with mastery goal orientation and confidence and mastery avoidance goal orientation have highly negative correlations each other. Second, achievement goal orientation form of specialized high school students were divided into 5 forms; 'execution avoidance(34.8%)', 'mastery orientation(20.8%)', 'approach(17%)', 'avoidance competition(14.9%)', and'mastery avoidance(12.5%)'. In preference to task difficulty, 'approach'group showed the highest average point and 'mastery avoidance'showed the lowest average point. The average point of 'approach' group was higher than other groups in confidence, but 'mastery orientation' group showed the highest average point. Through the results of this study, academic self-efficacy makes an effect by a certain direction in accordance with achievement goal orientation and it's necessary to access academic problems differently according to student's goal directivity. Therefore, it's necessary to provide educational method by student type based on explanation about academic self-efficacy of achievement goal orientation of specialized high school students and analysis on achievement goal orientation form.