• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.990-994
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• 2003

When the low cost IMU is used, the result of the stationary self alignment is not suitable for navigation. In this paper, an in-motion alignment method is proposed to obtain an accurate initial attitude of a low cost IMU based GPS/INS integration system. To design Kalman filter for alignment, large heading error model is introduced. And then Kalman filter is designed to estimate initial attitude error as the indirect feedback filter. In order to assess performance of the alignment method, computer simulations are carried out. The simulation results show that initial attitude error rapidly reduces.

• 산업기술연구
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• 제21권B호
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• pp.91-98
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• 2001

In this paper, center detection and motion analysis of a moving object are studied. Kohonen's self-organizing neural network models are used for the moving objects tracking and time delay neural networks are used for dynamic characteristic analysis. Instead of objects brightness, neuron projections by Kohonen Networks are used. The motion of target objects can be analyzed by using the differential neuron image between the two projections. The differential neuron image which is made by two consecutive neuron projections is used for center detection and moving objects tracking. The two differential neuron images which are made by three consecutive neuron projections are used for the moving trajectory estimation. It is possible to distinguish 8 directions of a moving trajectory with two frames and 16 directions with three frames.

• 한국멀티미디어학회논문지
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• 제14권12호
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• pp.1517-1527
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• 2011

This paper presents a motion capture based rehabilitation training system for a lower-limb paretic patient. The system evaluates the rehabilitation status of the patient by using the bend posture of the knees and the weight balance of the body. The posture of both legs is captured with a single camera using the planar mirror. The weight distribution is obtained by the Wii Balance Board. Self-occlusion problem in the tracking of the legs is resolved by using k-nearest neighbor based clustering with body symmetry and local-linearity of the posture data. To do this, we present data normalization and its symmetric property in the normalized vector space.

• 소음진동
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• 제4권2호
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• pp.221-230
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• 1994

This paper deals with the dynamic stability and the nonlinear behavior of a check valve system. The nonlinear equations of motion of fluid-valve interation model are derived, which are composed of the unsteady Bernoulli's equation included the jet flow mechanism and equation of motion of a check valve formulated by one degree of freedom. Also, the derived equations of motion are nondimensionalized. According to the change of the nondimensional parameters, the stabilities of the system are analyzed, and the nonlinear interaction responses of the check valve and the passing flow rate are obtained. As the results, the stability charts are constructed for the variation of nondimensional parameters. It is shown that self-excited vibrations exist in a check valve system. And also the Hopf bifurcation and the periodic doubling are found. The presented theoretical model of a check valve system can be utilized to the design and operation of a piping system with the check valve.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.62-66
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• 2010

This study presents velocities of bedload sediment transport in both longitudinal and lateral directions and applied in considering morphological change of straight open channel. The velocities of particle motion have obtained by considering the forces balance acting on particles on the bed between the drag, tangential component of the immersed weight of the particle, and Coulomb's resistive forces. Numerical profiles of particle motion velocities reveals good agreement in comparison between this study and Kovacs and Parker (1994). The evaluated velocities components of particle transport are get used to estimate bedload transport rate in considering morphological change of straight open channel. For the application, numerical solution is applied to laboratory experiment which shows very close solution profiles between this study and observed data of a self-formed straight channel.

• 대한조선학회지
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• 제24권2호
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• pp.36-46
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• 1987

This paper presents the results of seakeeping tests in a container ship model in irregular head waves. A time domain signal generating procedure is devised so that the wave maker behaves in accordance with the specified wave spectrum. The surface elevation of generated waves is measured and analysed to render the recorded wave spectrum for comparison with the specified one. Correction is made to the time domain signal until the differences between the two spectra become negligible. The motion responses and vertical acceleration of the self-propelled ship model are measured and analysed by both the spectral and the double amplitude methods. The two methods give nearly same statistical values. Finally the recorded spectra are compared with those calculated from the frequency domain motion analysis to show the credibility of the experimental results.

• 대한물리의학회지
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• 제9권4호
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• pp.455-463
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• 2014

PURPOSE: The purpose of this study was to compare the effects of Graston and self-myofascial release (SMR) techniques on knee joint flexibility, hamstring, and quadriceps strength. METHODS: Twenty subjects with hamstring shortness participated in this study. The subjects were assigned randomly to one of two groups: The Graston technique (GT) group received intervention using a Graston instrument for one minute, and the SMR group performed self-exercises using a foam roll for one minute. The range of motion (ROM) of the knee joint was measured by active knee extension test, and a handheld dynamometer was utilized to collect the hamstring and quadriceps muscle strength. This experiment was performed by two physical therapists. The significant level was set at ${\alpha}$=0.05. RESULTS: The results were as follows: 1) The ROM of the knee joint and quadriceps muscle strength were significantly increased in both groups. 2) Hamstring muscle strength was significantly reduced in both groups. 3) There were no significant differences between the GT group and SMR group for any variable. CONCLUSION: The results of this study suggest that SMR is an effective and easy technique for restoring proper muscle length and strength in subjects with hamstring shortness. We recommend that SMR technique be used for treat hamstring shortness in clinical setting and home-program.

• 한국전자통신학회논문지
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• 제14권3호
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• pp.619-626
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• 2019

나노 공정기술을 이용한 반도체 및 회로기술의 발전은 의료용 삽입형 기기(MID)의 소형화, 감도, 수명, 신뢰성을 더욱 향상했지만, 최근 MID의 지속적인 동작을 위한 전원의 지속적인 제공 여부가 중요한 도전과제 중 하나이다. 이러한 이유로 신체 내에서 다양한 생체 역학 에너지를 활용하는 자체 전원 이식형 의료기기가 최근에 많이 연구되고 있다. 본 논문에서는 TENG를 이용한 자가발전을 통해 재충전이 가능한 심장박동기를 개발하였다. 그리고 우리는 대형동물의 동작에 따라 삽입된 심장박동기에 내장된 TENG의 발전을 검증하였다. 동물의 움직임으로부터 수집되는 전력은 2.47V로 심장박동기에 센싱을 위해 필요한 전압(1.35V)보다 높은 전원을 획득할 수 있었다.

• 대한조선학회논문집
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• 제60권5호
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• pp.320-331
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• 2023

In this study, a model test was conducted using the soft-mooring technique to evaluate the added resistance of the ship in waves. The study also examined the specific factors that should be considered during the soft-mooring test. The main purpose of soft-mooring is to prevent drifting caused by waves by providing horizontal restoring forces. However, it can also create undesired restoring forces in the vertical direction. Therefore, we examined the restoring force of the ship's 6-DOF motion based on the arrangement of the soft-mooring and the height of the mooring connection point. We also checked the corresponding resonance period and drift distance. The soft-mooring test was conducted twice, once with self-propulsion and once without self-propulsion, allowing us to review the advantages and disadvantages of each test technique. The main parameters measured in these model tests were 6DOF motion and added resistance on the ship. We compared these measurements obtained from two different techniques (with and without self-propulsion). Additionally, we also compared the measurements based on the types of measuring sensors used (2D load cells on FP, AP, and 1D load cells on each mooring line) as well as the height of the mooring connection point.

• 재활간호학회지
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• 제13권2호
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• pp.140-150
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• 2010

Purpose: This study aims to find the factors that affect the degree of self-care performance in Parkinson's disease (PD) patients. Method: This study used a descriptive correlational design. The data were collected using a sample of 80 PD patients, from the university affiliated Parkinson Center in Busan. Pearson's correlations and multiple regression analyses were conducted using the SPSS 18.0. Results: The mean score of the self-care performance was 3.61 (${\pm}0.40$). The highest score observed of self-care performance subscale was medication subscale ($4.55{\pm}0.50$) and the lowest score was observed in the exercise subscale ($3.03{\pm}0.64$). The self-care performance had significant correlations with depression (r=-.32, p<.01), self-care knowledge (r=.28, p<.05), function of motion (r=.25, p<.05), ability of daily activity (r=.22, p<.05), self-efficacy (r=.24, p<.05), and support from medical staff (r=.24, p<.05). The significant predictors of self-care performance included depression (${\beta}=-.28$), status of employment (${\beta}=-.27$), self-care knowledge (${\beta}=-.21$), support from medical staff (${\beta}=-.28$), and educational level (${\beta}=-.28$), accounting for 34% of the variance in the self-care performance. Conclusion: Depression, self-care knowledge, medical support are significant predictors which affect the self-care performance with PD patients.