• 제목/요약/키워드: delayed measurement

검색결과 151건 처리시간 0.02초

시간지연을 고려한 간접 되먹임 구조 칼만필터의 수치안정성 향상 기법 (Numerical Stability Improvement Technique for Indirect Feedback Kalman Filter in Delayed-Measurement Systems)

  • 남성호;성창기;김태원
    • 한국군사과학기술학회지
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    • 제20권1호
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    • pp.25-32
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    • 2017
  • Most of weapon systems use aided navigation system which integrates inertial navigation and aiding sensors to compensate the INS errors increasing with the passage of time. Various aid sensors can be applied such as Global Navigation Satellite System (GNSS), radar, barometer, etc., but there might exist time delay caused by signal processing or transferring aid information. This time delay leads out-of-sequence measurements (OOSM) systems. Previously, optimal and suboptimal measurment update method for OOSM systems, where the time delay length are known, are proposed. However, previous algorithm does not guarantee the positive definite property of covariance matrix. In order to improve numerical stability for aided navigation using delayed-measurement, this paper proposes a new measurement covariance update algorithm be similar to Joseph-form in Kalman filter. Futhermore, we propose how to implement it in indirect feedback Kalman filter structure, which is commonly used in aided navigation systems, for time-delayed measurement systems. Simulation and vehicle test results show effectiveness of a proposed algorithm.

지연성근육통 예방을 위한 준비운동과 정리운동이 통증과 근활성도에 미치는 효과 (Effects of Warm-up and Cool-down Exercises for Preventing Delayed Onset Muscle Soreness on Pain and Muscle Activation)

  • 오덕원
    • 한국전문물리치료학회지
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    • 제20권1호
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    • pp.28-35
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    • 2013
  • The purpose of this study was to determine the effects of warm-up and cool-down exercises on pain and muscle activation of delayed onset muscle soreness after intense exercise. Delayed onset muscle soreness was caused by the eccentric exercise in the elbow flexor muscle of the non-dominant upper limb. Forty-four subjects volunteered to participate in this study and were randomly assigned to one of the following groups: warm-up and cool-down group, only warm-up group, only cool-down group, or control group with no intervention. The level of perceived pain using the visual analogue scale and electromyographic activation change in maximal voluntary isometric contraction were measured 4 times at the following times: 10 min, 24 hr, 48 hr, and 72 hr after the exercise. The results revealed the main effect between the groups and interaction effect between the group and measurement session (p<.05). The warm-up and cool-down group showed most favorable results with respect to reduced perceived pain level and increased muscle strength in most measurement sessions, and the only warm-up group showed significantly more decreased pain level than the control group at 24 hr and 48 hr and more increased muscle activation than the cool-down group at 48 hr (p<.05). However, there were no significant differences in pain level and muscle activation between the only cool-down group and control group at all measurement sessions (p>.05). The findings suggest that the warm-up exercise performed before an intense exercise had beneficial effects on the symptoms of delayed onset muscle soreness, whereas cool-down exercise performed after the intense exercise did not.

Effect of Vibratory Stimulation on Recovery of Muscle function from Delayed Onset Muscle Soreness

  • Koh, Hyung-Woo;Kim, Cheol-Yong;Kim, Gye-Yoep;Kim, Kyung-Yoon;Kim, Soo-Geun;Lee, Hong-Gyun
    • 운동영양학회지
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    • 제16권1호
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    • pp.43-50
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    • 2012
  • This study was designed to investigate the effect of vibratory stimulation on recovery of muscle function from delayed onset muscle soreness (DOMS). Volunteers performed 3 set of 70 % maximal voluntary eccentric muscle contraction and induced DOMS. volunteers were allocated to one of three treatment group after DOMS : group I (control), group II (ultrasound), group III (vibration). Maximal Voluntary Isometric Contraction (MVIC), Visual Analog Scale (VAS), Range Of Motion (ROM), Root Mean Square (RMS), Median frequency (MDF), Blood Serum Creatine Kinase (CK), Lactic dehydrogenase (LDH) were recorded at baseline, and 24, 48, 72 hours post-exercise. In MVIC measurement, there was a statistically significant difference in group III compared to group I (p < .05). In VAS measurements, there were a statistically significant difference in group II and III compared to group I (p < .05). In ROM measurement, there was a statistically difference in group II and III compared to group I (p < .05). In Muscle Volume with Ultrasonography measurement, there was no statistically significant difference in any groups (p > .05). In RMS and MDF measurement, there were a statistically significant difference in group II and III compared to group I (p < .05). In Blood samples of CK and LDH measurements, There were no statistically significant difference in any groups (p > .05). From the above result, Vibratory stimulation had a positive effect on recovery of muscle function from delayed onset muscle soreness. Further studies should be undertaken to ascertain the more effectiveness of vibratory stimulation and may be a promising treatment modality.

Kalman Filtering for Linear Time-Delayed Continuous-Time Systems with Stochastic Multiplicative Noises

  • Zhang, Huanshui;Lu, Xiao;Zhang, Weihai;Wang, Wei
    • International Journal of Control, Automation, and Systems
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    • 제5권4호
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    • pp.355-363
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    • 2007
  • The paper deals with the Kalman stochastic filtering problem for linear continuous-time systems with both instantaneous and time-delayed measurements. Different from the standard linear system, the system state is corrupted by multiplicative white noise, and the instantaneous measurement and the delayed measurement are also corrupted by multiplicative white noise. A new approach to the problem is presented by using projection formulation and reorganized innovation analysis. More importantly, the proposed approach in the paper can be applied to solve many complicated problems such as stochastic $H_{\infty}$ estimation, $H_{\infty}$ control stochastic system with preview and so on.

Optimal Filtering for Linear Discrete-Time Systems with Single Delayed Measurement

  • Zhao, Hong-Guo;Zhang, Huan-Shui;Zhang, Cheng-Hui;Song, Xin-Min
    • International Journal of Control, Automation, and Systems
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    • 제6권3호
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    • pp.378-385
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    • 2008
  • This paper aims to present a polynomial approach to the steady-state optimal filtering for delayed systems. The design of the steady-state filter involves solving one polynomial equation and one spectral factorization. The key problem in this paper is the derivation of spectral factorization for systems with delayed measurement, which is more difficult than the standard systems without delays. To get the spectral factorization, we apply the reorganized innovation approach. The calculation of spectral factorization comes down to two Riccati equations with the same dimension as the original systems.

원격조종을 위해 불확실한 시간 지연 측정값을 고려한 모션 추정 방법 (Motion Estimation Considering Uncertain Time Delayed Measurements for Remote Control)

  • 최민용;정완균;최원섭;이상엽;박종훈
    • 제어로봇시스템학회논문지
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    • 제14권8호
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    • pp.792-799
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    • 2008
  • Motion estimation is crucial in a remote control for its convenience or accuracy. Time delays, however, can occur in the problem because data communication is required through a network. In this paper, state estimation problem with uncertain time delayed measurements is addressed. In dynamic system with noise, after taking measurements, it often requires some time until that is available in the filter algorithm. Standard filters not considering this time delays cannot be used since the current measurement is related with a past state. These delayed measurements are solved with augmented extended Kalman filter, and the uncertainty of delayed time is also resolved based on an explicit formulation. The proposed method is analyzed and verified by simulations.

지연성 근육통(delayed onset muscle soreness)에 대한 경피선경자극(transcutaneous electrical nerve stimulation)의 효과 (Effects of Transcutaneous Electrical Nerve Stimulation on Delayed Onset Muscle Soreness)

  • 남기석;이윤주;김종만
    • 한국전문물리치료학회지
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    • 제4권3호
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    • pp.70-83
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    • 1997
  • The purpose of this study was to determine the effects of transcutaneous electrical nerve stimulation(TENS) on delayed onset muscle soreness(DOMS). Twenty males performed eccentric exercise of the elbow flexor. Subjects were randomly assigned to one of three groups: 1) a group ($n_1$=7) that received low frequency TENS (7 Hz), 2) a group ($n_2$=7) that received high frequency TENS (500 Hz), 3) a control group ($n_3$=6) that received no treatment. DOMS was induced in a standardised fashion in the non-dominant elbow flexor of all subjects by repeated eccentric exercise. Treatments were applied immediately following exercise and again at 24 hours and at 48 hours after. Subjects attended on three consecutive days for treatment and measurement of elbow flexion, extension and resting angle(universal goniometer), and pain(Visual Analogue Scale; VAS) on a daily basis. Measurements were taken after treatment. Analysis of results using repeated measures analysis of variance(ANOVA) and post hoc tests were as follows: 1) there were between groups differences in pain value at 48 hours after (p<0.05), 2) one-way ANOVA with repeated measurement for pain, resting angle, flexion angle and extension angle revealed significant differences within low frequency TENS group, 3) one-way ANOVA with repeated measurement for flexion angle revealed significant difference within high frequency TENS group.

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타이타늄 합금에서 산소발생전위 지연이 부동태 피막 특성과 국부부식 저항성에 미치는 영향 (Effect of Delayed Oxygen Evolution in Anodic Polarization on the Passive Film Characteristic and Localized Corrosion Resistance of Titanium Alloys)

  • 오유수;서동일;이재봉
    • Corrosion Science and Technology
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    • 제19권3호
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    • pp.156-162
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    • 2020
  • The objective of this study was to investigate delayed oxygen evolution and localized corrosion resistance of titanium alloys by performing potentiodynamic polarization, potentiostatic polarization, and Mott-Schottky measurements. Delayed oxygen evolution was compared among titanium alloys, 316 stainless steel, and platinum. Difference in delayed oxygen evolution between titanium alloys and other metals was attributed to specific surface characteristic of each metal. Delayed oxygen evolution of titanium alloys resulted from the predominant process of ionic conduction over electronic conduction. The effect of oxygen evolution on localized corrosion of titanium alloys was investigated using electrochemical critical localized corrosion temperature (E-CLCT) technique. Mott-Schottky measurement was performed to clarify the difference in film properties between titanium alloys and stainless steels. Titanium alloys were found to have much lower donor density than stainless steels by 1/28. These results indicate that delayed oxygen evolution has little influence on the concreteness of passive film and the resistance to localized corrosion of titanium alloys.

CHARACTERISTICS OF A NEW PNEUMATIC TRANSFER SYSTEM FOR A NEUTRON ACTIVATION ANALYSIS AT THE HANARO RESEARCH REACTOR

  • Chung, Yong-Sam;Kim, Sun-Ha;Moon, Jong-Hwa;Baek, Sung-Yeol;Kim, Hark-Rho;Kim, Young-Jin
    • Nuclear Engineering and Technology
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    • 제41권6호
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    • pp.813-820
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    • 2009
  • A rapid pneumatic transfer system (PTS) for an instrumental neutron activation analysis (INAA) is developed as an automatic irradiation facility involving the measurement of a short half-life nuclide and a delayed neutron counting system. Three new PTS designs with improved functions were constructed at the HANARO research reactor in 2006. The new system is composed of a manual system and an automatic system for both an INAA and a delayed neutron activation analysis (DNAA). The design and basic conception of a modified PTS are described, and the functions of system operation and control, radiation protection and emissions of radioactive gas are improved. In addition, a form of capsule transportation of these systems is tested. The experimental results pertaining to the irradiation characteristics with variation of the neutron flux and the temperature of the irradiation position with the irradiation time are presented, as is an analysis of the reference material for analytical quality control and uncertainty assessments.