• 제목/요약/키워드: Position Change

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Servo system에 대한 fuzzy control algorithm의 연구 (Development of fuzzy control algorithm for servo systems)

  • 이수흠;정원용;이현우;박창대
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.563-566
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    • 1991
  • This paper discusses the possibility of applying fuzzy logic controller in a microprocessor - based servomotor controller, such as servomotor position controller, which requires faster and more accurate response compared with other industrial processes. According to the fuzzy control rule made by tie analysis of error and error change, one Look-up table that contains various quantized step is made and appropriate initial error change is selected to the good responses.

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BLDC 모터의 구동방법과 정밀 반복제어 (A Driving Method and Precise Repetitive Control of BLDC Motor)

  • 이충환
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권6호
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    • pp.928-934
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    • 1998
  • This paper describes a fully digitalized driver for BLDC motors which is realized by a single chip microprocessor. The speed change can be done by using the signal obtained from the position detecting sensor and adjusting the pulse width at the input channel of power module. In order to establish a speed control system a repetitive control method is adopted to track a periodic refer-ence change in the BLDC motor system. The experimental results show accurate reference track-ing performance under the given periodic reference in the repetitive controller design.

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환자 자세가 간의 방사선 치료 시 선량에 미치는 영향 (The effect of patient position on dose in radiation therapy of liver cancer)

  • 정원석;김주호;김영재;신령미;오정훈;정건아;조준영;김기철;최태규
    • 대한방사선치료학회지
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    • 제26권1호
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    • pp.1-9
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    • 2014
  • 목 적 : 간암 치료 시 호흡으로 인한 움직임을 최소화하기 위해 환자 체위 변화에서 종양의 움직임과 용적 변화를 분석하고자 하였다. 대상 및 방법 : 간 세포암종(Hepatocellular Carcinoma) 환자 14명의 환자를 대상으로 시행하였다. 바로 누운 자세(Supine position)와 엎드린 자세(Prone position)에서 2가지 방법으로 환자 고정기구를 제작하고 영상을 획득하여 간 종양의 움직임과 용적 그리고 선량을 분석하였다. 결 과 : 바로 누운 자세(Supine position)와 엎드린 자세(Prone position) 에서 표적의 왼쪽-오른쪽(LR, Left-right) 움직임은 평균 $2.76{\pm}1.25mm$, $2.21{\pm}0.93mm$이고, 앞-뒤(AP, Anterior-posterior)와 상하(SI. Superior-inferior) 방향의 움직임은 각각 $4.02{\pm}1.63mm$, $11.56{\pm}3.08mm$, $3.36{\pm}1.17mm$, $7.45{\pm}1.96mm$이었다. 이를 이용한 엎드린 자세(Prone position)에서 치료 용적(Treatment volume)은 감소하였고, 이에 따라 정상간 용적은 증가 하였다. 결 론 : 호흡에 의한 간의 움직임을 최소화함으로써 치료 용적(Treatment volume)의 경계여유를 감소시킬 수 있었다. 즉 환자 자세 변화 특히 엎드린(Prone) 자세는 간의 움직임을 감소 시켜주고 정상 간의 용적을 증가 시킬 수 있을 것으로 사료된다.

교근 비대 환자에서 보툴리눔 A형 독소 주사 효과의 장기적 평가 (Long Term Evaluation of the Effect of Botulinum Toxin A Injection on the Masseteric)

  • 홍희숙;강승철;김종열;김성택
    • Journal of Oral Medicine and Pain
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    • 제30권1호
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    • pp.121-129
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    • 2005
  • 실험 대상자는 좌우측 교근에 보툴리눔 A 형 독소를 주입한 후 15개월 간 추적 조사가 시행된 11명이었다. 지원자들은 양측 교근에 보툴리눔 A형 독소를 주입하기 전, 주입 후 3개월, 주입 후 15개월 경과 후 각각 전산화 단층촬영을 시행하여 교근의 위축 정도를 관찰하였다. 측정은 하악골 하연을 기준면으로 하여 이 기준면의 상방 10 mm(position 1), 20 mm(position 2), 40 mm(position 3)의 세 위치에서 각각 두께와 면적을 측정하였다. 자입 지점은 position 1에 가장 근접했다. 먼저 교근의 두께 변화를 살펴보면 술후 3개월에 측정한 교근의 두께는 모든 position에서 감소하였으나 술후 15개월에는 술전과 비교할 때 유의한 두께 감소는 보이지 않았다. 반면에, 술후 3개월에 측정한 교근의 면적은 모든 position에서 감소하였으나 술후 15개월 경과 후에는 독소 주입 위치에서 가까운 position 1, 2에서는 면적 감소를 인정할 수 있었으나(position 1에서 10.7%, position 2에서 4.4%) 상대적으로 먼 position 3 에서는 면적 감소를 보이지 않았다. 이와 같은 연구 결과로 보아 독소 주입 15개월 후에도 약간의 교근 위축 효과가 남아 있는 것으로 판단되며, 위축량의 측정 시 일차원적인 두께 측정보다는 이차원적인 면적 측정이 더 정밀성이 있는 것으로 사료된다.

유엔기후변화협약의 농업부문 동향과 시사점 (Agriculture Under UNFCCC and Its Policy Implications)

  • 명수정
    • 한국기후변화학회지
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    • 제5권4호
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    • pp.313-321
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    • 2014
  • Agriculture is a vulnerable sector to climate change because it is a primary industry directly exposed to climate. At the same time, it is a sector emitting greenhouse gases during agricultural activities, thereby affecting climate change. However, agriculture is a nascent subject under the UNFCCC. The agriculture sector needs both adaptation and mitigation. Currently, co-benefit of adaptation and mitigation is emphasized during climate change negotiation. Developing country parties are in a position to focus on adaptation rather than mitigation. As a result, mitigation is not being addressed enough during climate negotiation. Agriculture has been addressed through Nairobi Work Programme and NAPA. Since current efforts for greenhouse gas reduction are not sufficient for stabilizing the atmospheric system of the Earth to prevent climate change, the agriculture sector should also be considered for greenhouse gas reduction. For this, MRV for small farmers in developing countries and incentives for their mitigation efforts should be developed in agriculture sector. In addition, it is necessary to strengthen international cooperation for developing capacities for vulnerable countries and people to climate change.

Discrepancies in Soft Tissue Profile of Patients for Orthognathic Surgery between Preoperative Lateral Facial Photograph, Lateral Cephalogram and Supine Position on Operation Table

  • Jung, Young-Eun;Yang, Hoon-Joo;Hwang, Soon-Jung
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제34권3호
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    • pp.180-185
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    • 2012
  • Purpose: An accurate preoperative analysis of the patient is essential in orthognathic surgery in order to acquire superior results. In profile, the location of the chin's position may change according to the neck's inclination. This may ultimately affect the amount of surgical movement. During acquisition of cephalometric radiographs, or in supine position, there is a discrepancy in the neck's inclination. This means that there are also various discrepancies between the actual profile and the various preoperative profile images. In the clinical situation, the decision in performing genioplasty usually lies in the analysis of the patient's profile on the operating table at the final stages of orthognathic surgery. This study aims to analyze the different preoperative profile images and to compare their discrepancies. Methods: Fifty eight patients undergoing orthognathic surgery were chosen. These patients were divided into three groups according to angle's classification of malocclusion, as class I, II or III. The right profile of these patients in centric occlusion was taken in natural head position (NHP). This was set as the 'actual profile image.' Another right profile image was taken on the operating table after insertion of the nasotracheal intubation and with muscle relaxants in effect. This was also taken in centric occlusion. The angle (denoted 'A') between the soft tissue glabella-pognion and the true vertical plane was found in the above-mentioned profile images and in the cephalometric radiographs. The differences of these values were analyzed. Results: There were differences in Angle 'A' in all of the preoperative images. These values were however, not statistically significant. Conclusion: In order to gain an esthetic profile during orthognathic surgery, the NHP is shown to be the most reliable position. Images reproducing such head positions should be used in the treatment planning process.

후두위치의 변화에 따른 Singer's Formant와 성대접촉률의 변화 연구 (Analysis of Singer's Formant & Close Quotient During Change of the Larynx Position)

  • 남도현;최성희;최재남;전석필;최홍식
    • 대한후두음성언어의학회지
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    • 제15권2호
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    • pp.98-111
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    • 2004
  • Background and Objectives : The purpose of this study is to analyze the difference of Fundamental Frequency(Hz), Closed Quotient(Qx ; %), Intensity(dB), Vocal tract length and width(cm), formant frequency(Hz), level of formant frequency(dB) depending on the larynx position. Materials and Methods : One professional male singer(career : 28 years) produced sustained vowel /a/,/e/,/i/,/o/,/u/ in two larynx position (higher, lower) with Dr. Speech and video fluoroscopy was used to quantify the vocal tract morphology. Results : In lower larynx position, CQ is increased 9.8% and Intensity is increased about 10% and level of Formant Frequency is increased. And also Vocal tract length is longer 2.4cm, Vocal tract width(Anterior width : 0.4cm, lateral width : 0.2cm) is wider than in higher larynx position. Conclusions : Singer's formant has a prominent spectrum envelope peak near 2400-2600Hz by clustering of F3, F4 and F5 near 3400Hz in lower larynx position.

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인체 무게 중심 분할에 따른 500m 숏트트랙 스피드 스케이팅 출발 기술 분석 (Analysis of the 500M Short track speed skating starting motion according to the center of gravity position ratio)

  • 백진호;정남주;한기훈;이용구;윤동섭;이용식
    • 한국운동역학회지
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    • 제13권3호
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    • pp.199-215
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    • 2003
  • The purpose of this study was to attempt new starting motion and supply present starting motion in the 500M short track speed skating according to the center of gravity position. The center of gravity position ratio was divided starting motion into five(type A : front 80%-back 20%, type B front 70%-back 30%, type C : front 50%-back 50%, type D : front 30%-back 70%, type E : front 20%-back 80%). The three dimension motion analysis with DLT(direct linear transformation) method was executed using two video cameras. The following conclusion was that It was appear that reaction and execution time in starting motion was the most short in type B. It was characteristic that step of skaters was shorten and center of gravity position ratio was not effect to change of the step in each event. It was appear that the displacement of type D and type E were longer than that type A and type B during the starting motion. It was appear that skill types of center of gravity position ratio to the front were lower than that to the back and contract a posture. Observing the above, it was conclusion that skill type B of center of gravity position ratio to the tent was more effect than that to the back. But it is important that these skill type was most used to the competition and estimate the result.

Evaluation of proximal contact strength by postural changes

  • Kim, Hee-Sun;Na, Hyun-Joon;Kim, Hee-Jung;Kang, Dong-Wan;Oh, Sang-Ho
    • The Journal of Advanced Prosthodontics
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    • 제1권3호
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    • pp.118-123
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    • 2009
  • STATEMENT OF PROBLEM. Proper proximal contact is important for maintaining and stabilizing the dental arch. However, the proximal contact strength (PCS) is not a constant value and can be affected by a variety of factors. PURPOSE. This study examined the influences of postural changes on the posterior PCS. MATERIAL AND METHODS. Twelve adults with a normal occlusion and had not undergone prosthetic treatment or proximal restoration were participated in this study. A metal strip was inserted into the proximal surface and removed at a constant velocity. The contact strength was measured in every contact point between canine to second molar in both arches. The PCSs were obtained initially in the upright position, secondly in the supine position and finally in the upright position again. All measurements were repeated after a 2 hour period. Statistical analysis was carried out using the Friedman test (P < .05). RESULTS. Generally, a decrease in PCS occurred when the posture was changed from the initial upright to supine position, while it increased when the posture was changed from the supine to upright position. A significant change was observed in all areas except for between the canine-first premolar in the maxilla and between the first molar-second molar in the mandible areas. CONCLUSION. The posterior PCS, which dentists generally believe to be a static feature of occlusion, is affected significantly by posture.

다중센서 융합 기반 무인잠수정 위치추정 개선 (Improvement of Position Estimation Based on the Multisensor Fusion in Underwater Unmanned Vehicles)

  • 이경수;윤희병
    • 한국지능시스템학회논문지
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    • 제21권2호
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    • pp.178-185
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    • 2011
  • 본 논문은 상태변수 평준화 및 되먹임구조를 이용하여 무인잠수정의 위치추정을 개선하기 위한 다중센서 융합 기반의 위치추정 알고리즘을 제안한다. 이를 위해 먼저 상대적으로 오차가 큰 주 센서인 INS와 오차가 작은 보조센서인 DVL에서 측정되는 상태변수를 예측단계 이전에 융합하여 상태변수 평준화 과정을 수행한다. 그 다음, 평준화된 상태변수를 각 필터에 입력하여 예측 및 수정단계의 칼만 필터링 과정을 통해 최종 수정된 상태변수를 융합시키며, 마지막으로 이를 다시 주센서에 되먹임함으로서 무인잠수정의 위치추정을 개선한다. 평가를 위해 무인잠수정의 기동모델에 대한 시뮬레이션을 실시하여 기동경로를 생성하고 제안 알고리즘을 적용하여 위치추정 성능을 확인한다. 평가 결과, 제안 알고리즘이 다중센서 융합 알고리즘 중 가장 우수한 위치추정 성능을 보였으며, 또한 기동침로가 변경되는 구간에서도 강인한 위치추정이 가능하다는 것이 증명되었다.