• 제목/요약/키워드: baseline length

검색결과 235건 처리시간 0.026초

Effects of Motor Imagery Training and Balance Training on Static Balance: A Quasi-Experimental Study

  • Gim, Mina;Choi, Junghyun;Ga, Heayoung
    • 국제물리치료학회지
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    • 제11권1호
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    • pp.1999-2004
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    • 2020
  • Background: Although studies on physical motor learning through motor imagery training have been conducted in various fields, studies on its effectiveness are still considered insufficient. Objective: To investigate the effect of motor imagery training and balance training on static balance of asymptomatic adults in their 20s. Design: A quasi-experimental study. Methods: Thirty-six adults in their 20s who passed the tandem stance test were randomized to the motor imagery training group (MIG, n=12), motor imagery with balance training group (MIBG, n=12), and balance training group (BG, n=12). Each group underwent their respective interventions three times a week for four weeks, and changes in static balance were analyzed using multivariate analysis of variance. Results: Trace length was significantly lower in the MIBG than in the MIG and BG (P<.05), and a significant reduction in trace length in the MIBG was observed after the intervention as compared to the baseline (P<.05). Furthermore, a significantly lower velocity was observed in the MIBG than in the MIG and BG (P<.05), and a significant reduction of velocity in the MIBG was more observed after the intervention compared to the baseline (P<.05). Conclusion: These results suggest that motor imagery training enhance static balance in healthy college students.

HD급 영상을 효율적으로 복호하기 위한 CAVLC 복호화기 VLSI 설계 (Efficient CAVLC Decoder VLSI Design for HD Images)

  • 오명석;이원재;김재석
    • 대한전자공학회논문지SP
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    • 제44권4호통권316호
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    • pp.51-59
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    • 2007
  • 본 논문에서는 H.264/AVC 엔트로피 부호화기의 베이스라인(Baseline)과 익스텐디드(Extended) 프로파일에서 사용되는 내용 기반 가변 길이 부호화(CAVLC: Context-based Adaptive Variable Length Coding)의 하드웨어 기반 복호화기 구조를 제안한다. 기존에 제안되었던 CAVLC 복호화기 하드웨어 구조는 5단계의 블록으로 설계되어 있고, 각 블록들이 유효비트를 얻기 위해서는 컨트롤러블록과 Accumulator블록을 거쳐 구해진다. 이때 레지듀얼 계수가 많을수록 이 과정을 여러 번 반복하게 되기 때문에 복호화 효율이 떨어진다. 본 논문에서는 이러한 유효비트를 구하는 과정을 줄이기 위해 2가지 방법을 제안한다. 한 가지 방법은 5단계로 이루어져 있던 블록을 4단계의 블록으로 줄이는 것이고 다른 한 가지 방법은 컨트롤러에 의한 덧셈 연산단계를 생략함으로써 블록별 유효비트를 효율적으로 구하는 것이다. 제안된 방법을 적용한 구조에 실험한 결과 하드웨어의 크기는 비슷하면서 하나의 매크로블록을 처리하는데 요구되는 평균 사이클 수가 기존의 방식보다 약 26% 줄었고 0.18um 표준 셀 라이브러리로 합성한 결과 14.2K 게이트를 가졌다.

슬랙스 형태 적합성 평가의 정량적 평가 기준 설정 (Establishing Quantitative Evaluation Standards for the Shape Fitness test of Slacks)

  • 김선영
    • 한국의류산업학회지
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    • 제18권5호
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    • pp.695-707
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    • 2016
  • This study presents quantitative evaluation standards for the shape fitness test, conducted in the process of the slacks fit test. This study aims to quantify appearance sensory test of slacks for the objectification of qualitative evaluation methods in existing shape fitness tests. The subjects were women of standard body type between the ages of 18 and 24. Slacks differing in their ease in waist girth, hip girth, crotch length and knee length were designed to test their shape fitness. The gap volume distribution between the body and slack, angle of the baseline by body part, and ratio of total thickness from the sideline using 3D human body scan data (which reflect the results of the appearance sensory test) were presented as quantitative evaluation standards. There were less wrinkles in the wrinkle/overstretch and ease categories of the appearance sensory test; in addition, ease was adequate and small enough to comfortably perform basic human activities in the standing upright posture. The gap volume distribution analysis between body and slacks showed that curves increased in the slacks surface along with an increase of ease in slacks and suggested that wrinkles also increased. In the baseline's horizontal categories in terms of a $0^{\circ}$ horizontal angle, the range of angles were evaluated as adequate by the clothing expert group. The total thickness ratio of 0.5:0.5 divides into the sideline from the baseline.

Wing Design Optimization of a Solar-HALE Aircraft

  • Lim, JaeHoon;Choi, Sun;Shin, SangJoon;Lee, Dong-Ho
    • International Journal of Aeronautical and Space Sciences
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    • 제15권3호
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    • pp.219-231
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    • 2014
  • We develop a preliminary design optimization procedure in this paper regarding the wing planform in a solar-powered high-altitude long-endurance unmanned aerial vehicle. A high-aspect-ratio wing has been widely adopted in this type of a vehicle, due to both the high lift-to-drag ratio and lightweight design. In the preliminary design, its characteristics need to be addressed correctly, and analyzed in an appropriate manner. In this paper, we use the three-dimensional Euler equation to analyze the wing aerodynamics. We also use an advanced structural modeling approach based on a geometrically exact one-dimensional beam analysis. Regarding the structural integrity of the wing, we determine detailed configuration parameters, specifically the taper ratio and the span length. Next, we conduct a multi-objective optimization scheme based on the response surface method, using the present baseline configuration. We consider the structural integrity as one of the constraints. We reduce the wing weight by approximately 25.3 % from that in the baseline configuration, and also decrease the power required approximately 3.4 %. We confirm that the optimized wing has sufficient flutter margin and improved static longitudinal/directional stability characteristics, as compared to those of the baseline configuration.

3차원 기선벡터망 조정기법에 의한 국가기본점의 성과산정(KTRF94) (Adjustment Computation of the National Fundamental Stations Using 3-D Baseline Vectors(KTRF94))

  • 이영진
    • 한국측량학회지
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    • 제16권1호
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    • pp.85-94
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    • 1998
  • 국립지리원에서는 정밀측지망측량 사업의 일환으로 국가기본망의 구축을 위한 사업에 착수하였으며, 1996년도에는 전국 31점 규모의 GPS망을 관측한바 있다. 이 망은 변장 40 km-120 km(평균 67.4 km) 인 220개의 기선으로서 구성되었다. 본 연구에서는 3차원 기선벡터로 조합된 3차원망을 최소제곱법에 의해 조정하고 산정된 한국측지 기준좌표계94(KTRF94)성과를 제시하였다. VLBI관측점과의 편심관측에 의해 결정된 경위도원점의 ITRF94 좌표를 고정점으로 사용하였으며 조정정확도는 수평위치 1 cm, 높이 3 cm 인 것으로 분석되었다. 아울러 WGS84좌표와 KGS95좌표와의 차이에 대해서도 분석되었다.

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The Suggestion of Effective Measurement Techniques for Positioning Under Poor GPS Reference Network Condition

  • Park, Joon-Kyu;Jung, Kap-Yong
    • 한국측량학회지
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    • 제31권6_2호
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    • pp.539-547
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    • 2013
  • This research is suggesting the most effective positioning method for GPS based positioning when no GPS reference point is available in the neighborhood. For this purpose, we carried out positioning of the IGS realtime observatories in Australia in various conditions. According to the research, we were certainly assured the one reference point with a short baseline length is more effective for differential positioning than multiple reference points with a long baseline distance beyond 1,000km and suggested the precise point positioning based positioning method can be an excellent substitute when no reference point is available around an unknown point. The research result may be used as the basic data for accurate positioning in poor reference point environments, especially in Antarctica.

GPS를 이용한 자세 측정 시스템의 미지정수 결정기법 (An Integer Ambiguity Resolution Method for GPS Attitude Determination)

  • 박찬식;김일선
    • 제어로봇시스템학회논문지
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    • 제5권1호
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    • pp.62-68
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    • 1999
  • The attitude of a vehicle can be precisely determined using GPS carrier phase measurements from more than two antennas attached to a vehicle and an efficient integer ambiguity resolution technique. Many methods utilizing the known baseline length as a constraint of independent elements of integer ambiguities are proposed to resolve integer ambiguity at real time. Three-dimensional search space is reduced to two-dimensional search space with this constraint. Thus the true integer ambiguity can be easily determined with less computational burden and fewer number of measurements. But there are still strong requirements for the real time integer ambiguity resolution, which uses single epoch measurement of long baseline. In this paper, a new constraint from the geometry of multiple baselines is derived. With this new constraint, two-dimensional search space is further reduced to one-dimensional search space. It makes possible to determine integer ambiguity with single epoch measurement. The proposed method is applied to real data to show its effectiveness.

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GNSS 자세결정시스템의 오차해석 (Error Analysis of GNSS Attitude Determination System)

  • 황동환;이상정;박찬식
    • 제어로봇시스템학회논문지
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    • 제12권3호
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    • pp.300-306
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    • 2006
  • In this paper an error analysis of 3-dimensional GNSS attitude determination system is given. The attitude error covariance matrix is derived and analyzed. It implies that attitude errors are affected by the baseline length and configuration, the satellites numbers and geometry, receiver measurement noises and the nominal attitude of the vehicle. By defining Euler Angle Dilution Of Precision (EADOP) which is analogous to GDOP, roll, pitch and yaw errors can be efficiently analyzed. However the expression of the attitude error is too complex to get some intuitions. Therefore with a commonly adopted assumption, new expressions for attitude error are derived. The formulas are easy to compute and represent the attitude error as a function of the nominal attitude of a vehicle, the baseline configuration and the receiver noise. Using the formula, the accuracy of the attitude can be analytically predicted without the computer simulations. Applications to some widely used configurations reveal the effectiveness of the proposed method.

Analysis of success rate of GPS carrier phase ambiguity resolution in Korea peninsula

  • Soo, Son-Ji;In, Jee-Gyu
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.114.1-114
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    • 2001
  • GPS Receiver gives pseudorange Doppler and integrated carrier phase for measurements to compute navigation information. Thought the integrated carrier phase can be transfer to the equal domain as pseudorange by multiplying the wave length of the received signal, in order to get position information from the carrier phase measurements the integer ambiguity should be resolved. And differencing technique is generally used to eliminate the common error terms of the integrated carrier phase measurements between robber and server. In short baseline double-differencing operation has effect on elimination the common biases for both stations and thus ambiguity resolution are to be reliable. But the baseline increases, the integer ambiguity resolution is hardly, due to the correlated common error is increase ...

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GPS를 이용한 자세결정에서 Unscented Kalman Filter를 이용한 성능 향상 (Performance Improvement in GPS Attitude Determination Using Unscented Kalman Filters)

  • 천세범;이은성;강태삼;지규인;이영재
    • 제어로봇시스템학회논문지
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    • 제11권7호
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    • pp.621-626
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    • 2005
  • With precise GPS carrier positioning result, we can get attitude information if GPS antenna has adequate attaching position on the vehicle. In this case, baseline length information can be bandied as an additional measurement or constraint. In this paper, we have proposed a method to improve the attitude accuracy. To overcome nonlinearity of baseline observation model, we analyze attitude estimation result using existing estimation method like a least square method and Kalman filter, and apply a new nonlinear estimation method an unscented Kalman filter Finally we confirm the improvement of attitude estimation result in the case of appling the unscented Kalman filter.