• Title/Summary/Keyword: 1 자유도

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Control Net Generation for Parametric control of freeform shape (자유형상의 파라메트릭 변형을 위한 조정 다각형 생성)

  • 박현풍;이관행
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.10b
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    • pp.667-669
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    • 2003
  • 특징 형상의 조합으로 표현될 수 없는 자유 형상을 가진 제품이 늘어남에 따라 자유형상을 효율적으로 변형시키는 기법이 필요하다. 여러 가지 자유형상 변형기법(FFD) 가운데에서 자유 형상을 파라메트릭하게 컨트롤하기 위해서는 조정 다각형 기반의 형상 변형 기법이 적합하다. 이에 따라 본 연구에서는 FFD 기법을 적용하여 자유형상 모델을 파라메트릭하게 컨트롤하기 위해 입력 모델에 대한 조정 다각형을 자동으로 생성하는 알고리즘을 제안하였다. 제안된 알고리즘은 크게 기본 조정 다각형 생성과 조정 다각형 최적화 단계로 나누어진다. 기본 다각형 생성에서는 1)입력모델을 직교 3방향에 투영, 2)투영된 결과에 대해 2차원 조정 다각형을 생성, 3)2차원 조정 다각형을 조합하여 3차원 기본 조정 다각형 생성의 단계를 거친다. 조정 다각형 최적화 단계에서는 기본 조정 다각형에 에지 및 면 연산자를 적용하여 입력 모델에 더욱 근사하는 최종 조정 다각형을 생성한다. 예제에서는 제안된 알고리즘을 통해 자동으로 생성된 조정다각형을 자동차 모델에 적용하여 모델의 형상을 변화시킨 결과를 보였다.

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Teacher Perception and Practice on Free Semester Science Assessment (자유학기제 과학과 평가에 대한 교사의 인식과 실제)

  • Kim, Yura;Choi, Aeran
    • Journal of The Korean Association For Science Education
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    • v.39 no.1
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    • pp.143-160
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    • 2019
  • This study investigated 15 science teachers' perception and practice on free semester and science assessment. We analyzed frequencies of teacher choice for closed questions and used constant comparative method for teacher description and individual interview. Most teachers determined a low ranking for changes in assessment methods and mentioned a lack of objectivity on free semester assessment, unsystematic free semester assessment, and more importance on student activity and interest in science instruction. Most teachers understood process-based assessment as a direction of free semester assessment and teachers mentioned positive aspects for students or teacher difficulties dependent on their perception on process-based assessment. Half of the teachers failed to implement student self-assessment and student peer-assessment due to subjectivity and complexity. Some teachers did not provide feedbacks to students due to a lack of time and did not use certain assessment methods due to a lack of knowledge of the assessment. Teachers who did not have an experience of discussions in a teacher learning community mentioned reasons regarding a small number of the same grade teachers and inactive attitude of colleagues. Teachers who did not participate in professional development programs mentioned a lack of teacher understanding of free semester, participation of the teacher in charge, and teacher choice of participation as reasons.

The Impact of the Incheon Free Economic Zones on Regional Disparities in Incheon (인천 경제자유구역이 인천시 자치구(군)간 지역불균형에 미치는 영향분석)

  • Kim, Bora;Choi, Jinmu
    • Journal of the Economic Geographical Society of Korea
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    • v.17 no.1
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    • pp.86-97
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    • 2014
  • Incheon Free Economic Zone is the first free economic zone specified in 2003 in Korea. Previous research on the Free Economic Zone has focused on the activation of the free economic zone or foreign investment issue at the level of the national economic plan. Related to the development of a free economic zone, studies are currently insufficient on the relevance of the local economy, the development of linkages with hinterland, and the balanced regional development. Therefore, this study tried to investigate the impact of Incheon Free Economic Zone to the local economy through analyzing the causes and characteristics of the imbalance between the regions in Incheon by comparing before (1996~2002) and after (2003~2009) of the Incheon Free Economic Zone legislation (2003). The result shows that development of the free economic zone has not been connected to the local economy activation and the ripple effect on the old town in Incheon. Further, the construction of a large apartment and infrastructure in the free economic zones have increased the disparity between the free zones and the old town.

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3DOF Force-Reflection Interface (3자유도 힘 반향 역감장치)

  • 강원찬;김동옥;신석두;김영동
    • The Transactions of the Korean Institute of Power Electronics
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    • v.4 no.5
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    • pp.455-461
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    • 1999
  • In this paper, we present the 3DOF force-rei1ecting interface which allows to acquire force of objc'Ct within a a virtual environment. This system is comlxlsed of device, virtual environment model, and force-rei1ecting r rendering algorithm. We design a J DOF force reflecting device using the pc$\alpha$allel linkage, torque shared by W wire, and the controller of system applied by impedance control algorithm. The force reflecting behaviour i implemented as a function position is equivalent to controlling the mechanical impedance felt by the user. E Especially how force should be supplied to user, we know using a God-Object algorithm As we experiment a system implement$\varepsilon$d by the interface of 3D virtual object and 3DOF force reJll'Cting i interface, we can feel a contact, non contact of :)D virtual object surface and sensin앙 of push button model.utton model.

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Trajectory Optimization for Nonlinear Tracking Control in Stratospheric Airship Platform (비선형 추종제어를 위한 성층권비행선의 궤적 최적화)

  • Lee, Sang-Jong;Bang, Hyo-Choong;Chang, Jae-Won;Seong, Kie-Jeong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.37 no.1
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    • pp.42-54
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    • 2009
  • Contrast to the 6-DOF nonlinear dynamic modeling of nonlinear tracking problem, 3-DOF point-mass modeling of flight mechanics is efficient and adequate for applying the trajectory optimization problem. There exist limitations to apply an optimal trajectory from point-mass modeling as a reference trajectory directly to conduct the nonlinear tracking control, In this paper, new matching trajectory optimization scheme is proposed to compensate those differences of mismatching. To verify performance of proposed method, full ascent three-dimensional flight trajectories are obtained by reflecting the real constraints of flight conditions and airship performance with and without jet stream condition. Then, they are compared with the optimal trajectories obtained from conventional method.

Dynamic Interaction Analysis of Train and Bridge According to Modeling Methods of Maglev Trains (자기부상열차의 모델링방법에 따른 열차-교량의 동적상호작용 해석)

  • Jung, Myung-Rag;Min, Dong-Ju;Lee, Jun-Seok;Kwon, Soon-Duck;Kim, Moon-Young
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.24 no.2
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    • pp.167-175
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    • 2011
  • The purpose of this study is to examine the impact that change in speed and modeling methods has on maglevs' runnability. The study constructed equations of motion on 4-DOF, 6DOF, and 10-DOF vehicles respectively and carried out numerical analysis, applying 4th Runge Kutta method, in order to run six different model maglev as changing the vehicles speed on the same bridge that had 2000 to 1 deflection. The analysis revealed that maglev's runnability improved as speed was lower and the specific model had higher number of bogey and EMS.

Effects of Feeding Type of Concentrates During Growing Period and Slaughter Age on Growth Performance, Feed Efficiency and Carcass Characteristics in Growing-Fattening Holstein Steers (홀스타인 거세우에 대한 육성기 농후사료 급여형태 및 출하월령이 성장발육, 사료이용성 및 도체특성에 미치는 효과)

  • Kang, S.W.;Jeong, H.Y.;Ahn, B.S.;Oh, Y.K.;Son, Y.S.
    • Journal of Animal Science and Technology
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    • v.46 no.6
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    • pp.989-998
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    • 2004
  • The objectives of this work was to investigate the effects of feeding type of concentrates during growing period and slaughter age on growth performance, feed efficiency and carcass characteristics in growing-fattening Holstein steers. Treatments were two concentrates feeding types(ad libitum or restricted 1.9% of BW) and three slaughter ages(at 19, 22 or 25 mo). Body weight at slaughter was numerically higher(approx. 8.3%) for the restricted than the ad libitum feeding groups. TDN intake rate was higher(8.4%) for the restricted than the ad libitum feeding groups. One mo slaughter delay increased TDN intake by 4%. Despite the lack of significances, higher back fat thickness and rib-eye area appeared in the restricted feeding or the late slaughter groups compared with the ad libitum feeding or the early slaughter groups. Marbling score(mean 2.46) numerically increased when the steers were restrictively fed concentrates compared with the ad libitum feeding groups. In addition, significant increases in the marbling score were associated with the slaughter age delay. In economic analysis, increases in total income were associated with the restricted feeding and the slaughter age delay. Whereas the highest monthly income appeared in the restricted feeding-and-slaughter at 22 mo group. In conclusion, the optimal feeding system may be 1) the restricted concentrates feeding(1.9% of BW) during growing period and 2) the late slaughter age(22${\sim}$25 mo of age) in growing-fattening Holstein steers fed rice straw.

Recognition of Free Inquiry Activity and its Effects on the Science Inquiry Ability of Middle School Students (자유 탐구 활동에 대한 중학생들의 인식 및 자유 탐구 활동이 중학생들의 과학 탐구능력에 미치는 영향)

  • Byun, Sun-Mi;Kim, Hyun-Joo
    • Journal of The Korean Association For Science Education
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    • v.31 no.2
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    • pp.210-224
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    • 2011
  • The purpose of this study is to analyze students' recognition of the free inquiry activity and to investigate what effect the free inquiry activity of the 2007 Revised Educational curriculum revision has on the science inquiry ability of middle school students. To conduct the research we worked with 262 female students, 8 classes of first graders in a middle school. Among them, 4 classes were taught in free inquiry activity and the remaining 4 classes were taught in the traditional way. The results of Likert-questionnaire indicate that students were learning about cooperative spirit through group investigation activities and discussions and did not take the free inquiry activity as a hard activity. Also they showed positive reaction agreeing that this activity is both a helpful method in learning science and interesting. However, it seemed that the investigation tends to flow between the leading 1~2 members of the group and showed difficulty in carrying out the investigation as a group after school hours. It showed there are few problems and obstacles in operating the free inquiry activity. The free inquiry activity did not give any meaningful influence on the improvement of science inquiry ability of students. Integrative inquiry process skills did not give a relevant influence, however, it showed a meaningful influence on the improvement of basic inquiry process skills. Especially, among the low-ranking element of basic inquiry process skills, it enhanced the capacity for prediction.

Validation of the Korean Version of Free Will and Determinism Scale (FAD-Plus) using Confirmatory Factor Analysis - The Relationship Between Belief in Free Will and Correspondence Bias - (확인적 요인분석을 통한 한국판 자유의지와 결정론 척도(FAD-Plus)의 타당화 - 자유의지에 대한 믿음과 귀인편향의 관계 -)

  • Ahn, Jaekyung;Han, Sanghoon;Choi, Yimoon
    • Korean Journal of Forensic Psychology
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    • v.12 no.1
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    • pp.35-51
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    • 2021
  • People's belief in free will is important in determining the causes and responsibilities of human behavior. Over the past decades, there has been debate about belief in free will in the fields of neuroscience, philosophy, ethics, and criminal law. The Free Will and Determinism Scale (FAD-Plus; Paulhus & Carey, 2011) is a test tool that measures the components related to the belief in an individual's free will. This study conducted a confirmatory factor analysis of 1,000 ordinary people of various age groups and socio-economic backgrounds based on previous studies that conducted an exploratory factor analysis (Study 1). The author has secured the reliability and validity of a number of measures. Furthermore, it was examined how the sub-item of the FAD-Plus scale, 'belief in free will,' was related to correspondence bias and locus of control (Study 2). As a result of analyzing a total of 83 subjects, high belief in free will had a positive correlation with punishment judgment for negative behavior and internal attribution, but there was no significant relationship in reward judgment for positive behavior. Based on the study results, it was proven that the FAD-Plus is valid for the general public as well, and the relationship between belief in free will, attribution bias, locus of control and behavior judgment was examined. The limitations of this study, policy implications, and research directions are discussed.

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