• International Journal of Control, Automation, and Systems
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• v.4 no.3
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• pp.325-332
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• 2006

The dynamic responses of human standing postural control were investigated when subjects were exposed to long-term horizontal vibration. It was hypothesized that the motion of standing posture complexity mainly occurs in the mid-sagittal plane. The motor-driven support platform was designed as a source of vibration. The AC Servo-controlled motors produced anterior/posterior (AP) motion. The platform acceleration and the trunk angular velocity were used as the input and the output of the system, respectively. A method was proposed to identify the complexity of the standing posture dynamics. That is, during AP platform motion, the subject's knee, hip and neck were tightly constrained by fixing assembly, so the lower extremity, trunk and head of the subject's body were individually immovable. Through this method, it was assumed that the ankle joint rotation mainly contributed to maintaining their body balance. Four subjects took part in this study. During the experiment, the random vibration was generated at a magnitude of $0.44m/s^2$, and the duration of each trial was 40 seconds. Measured data were estimated by the coherence function and the frequency response function for analyzing the dynamic behavior of standing control over a frequency range from 0.2 to 3 Hz. Significant coherence values were found above 0.5 Hz. The estimation of frequency response function revealed the dominant resonance frequencies between 0.60 Hz and 0.68 Hz. On the basis of our results illustrated here, the linear model of standing postural control was further concluded.

• Journal of Engineering Education Research
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• v.24 no.4
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• pp.21-29
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• 2021

The objective of this research is to devise a BARS evaluation system as a performance evaluation plan for non-face-to-face capstone design and to verify the validity through the expert FGI as the remote education is highlighted as a new normal standard in the post corona epoch. The conclusion of this research is as follows. First, the non-face-to-face capstone design is a competency centered subject that allows you to develop the engineering and majoring knowledge and its function and attitude, and the achievement of program outcome is the objective competency, and the researcher proposes the BARS method evaluation, one of competency evaluation method, as a new performance evaluation plan. Second, for the evaluation of PO achievement of non-face-to-face capstone design, the researcher deduced 20 behavior identification standard(anchor) of BARS evaluation system, and developed the achievement standard per 4 levels. Third, as the evaluation tool of non-face-to-face capstone design, the presentation data(PPT), presentation video, product such as trial product(model), non-face-to-face class participation video, discussion participating video, team activity report, and result report for the evidential data of BARS evaluation were appeared as proper. Finally, the BARS evaluation plan of non-face-to-face capstone design would be efficiently made through the establishment of evaluation plan, the establishment of grading standard of BARS evaluation scale, the determination of evaluation subject and online BARS evaluation site.

• The Journal of the Society of Stroke on Korean Medicine
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• v.12 no.1
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• pp.61-67
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• 2011

Background : Prevalence of spasticity because of stroke are 40% patients after 12 month. Spasticity caused decrease of range of motor, motor function, and active daily living. Electroacupuncture widely used stroke. But it is been studied by systematic review between spasticity and electroacupuncture. This study is aimed to efficacy of electroacupuncture for spasticity because of stroke. Methods : We had used pubmed(www.pubmed.com) and cochrane library(www.thecochranelibrary.com) database. Limits are'human','randomized controlled trial'and'all adult 19+ years'in pubmed. The period was until 15, september, 2011. We used MeSH(Medical Subject Headings terms. The search words were'stroke'[mesh],'muscle spasticity'[mesh and 'electroacupuncture'[mesh]. In cochrane library, we used spasticity and electroacupuncture in cochrane library. We found 19 studies. But only 3 studies were included for inclusion criteria. Results : The appropriate 3 studies were different from subject, acupoint, duration of treatment, endpoint and etc. But these studies were effective for spasticity because of stroke. Conclusion : These studies were not meta analysis because of heterogeneity. But the above results might explain the electroacupuncture were effective for spasticity and further study needed to verify and standard electroacupuncture study for spasticity.

• Journal of Korean Academy of Nursing
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• v.33 no.2
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• pp.179-188
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• 2003

Purpose: This study was designed to create the job description of Korean transplantation nurse practitioner and examine performance frequencies, criticality, and difficulties of task elements. Method: The sample consisted of 63 nurses and coordinators who performed duties related to transplantation at medical center in Korea. A survey method was used, and the questionnaire included frequencies, criticality, and difficulties of task elements in job description by the DACUM method. Using SPSS WIN 10.0, descriptive statistics such as frequency distribution, means, and standard deviations were conducted to examine the subject's general characteristics, the frequencies, criticality, and difficulties of task performance. Result: The job description of transplantation nurse practitioners revealed 5 duties, 22 tasks, and 85 task elements. On the all five duties, the averages of the performance frequency, criticality, and difficulty were 2.41, 3.38, and 2.78, meaning that the respondents rarely perform the 5 duties, but consider them critical and easy to perform. Conclusion: The job description of the transplantation nurse practitioner included duty, task, and task element and definition of job completed. Thus we recommended a data based trial to confirm and validate the information gathered.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.61-68
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• 1991

The system such as railway bridge can be modelled as the restrained beam with intermediate supports. This kind of structures are subject to the moving load, which has a great effect on dynamic stresses and can cause sever motions, especially at high velocities. Therefore, to analyze the dynamic characteristics of the system due to the moving load is very important. In this paper, the governing equation of motion of a restrained beam subjected to the moving load is derived by using the Hamilton's principle. The orthogonal polynomial functions, which are trial functions and satisfying the geometric and dynamic boundary conditions, are obtained through simple procedure. The dynamic response of the system subjected to the moving loads is obtained by using the Galerkin's method and the numerical time integration technique. The numerical tests for various constraint, velocity and boundary conditions were preformed. Furthermore, the effects of mass of the moving load are studied in detail.

• Korean Journal of Applied Biomechanics
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• v.12 no.1
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• pp.125-133
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• 2002

The purpose of this study was to develop a method for estimating 3-D coordinates of lower trunk muscles using orientation angles during a motion. Traditional 3-D motion analysis system with DLT technique was used to track down the locations of eight reference markers which were attached on the back of the subject. In order to estimate the orientations of individual lumbar vertebrae and musculoskeletal parameters of the lower trunk muscle, the rotation matrix of the middle trunk reference frame relative to the lower trunk reference frame was determined and the angular locations of individual lumbar vertebrae were estimated by partitioning the orientation angles (Cardan angles) that represent the relative angles between the rotations of the middle and lower trunks. When the orientation angles of individual intervertebral joints were known at a given instant, the instantaneous coordinates of the origin and insertion for all selected muscles relative to the L5 local reference frame were obtained by applying the transformation matrix to the original coordinates which were relative to a local reference frame (S1, L4, L3, L2, or L1) in a rotation sequence about the Z-, X- and Y-axes. The multiplication of transformation matrices was performed to estimate the geometry and kinematics of all selected muscles. The time histories of the 3-D coordinates of the origin and insertion of all selected muscles relative to the center of the L4-L5 motion segment were determined for each trial.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.283-287
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• 1993

We constructed morphological filter for single sweep records of event-related potential (ERP), especially P300 waveform. By combining 4 basic operations; erosion, dilation, opening and closing, we can derive any desired filters whose property fits the current objectives. The morphological filter for single sweep records of ERP was constructed by taking account of the features of the signal and noise components. The morphological filter has superior properties of separating the signal ancl the noise even existing within a same frequency band. The constructed morphological filter was tested by using simulation data of ERP and then applied to actual ERP data of a normal subject. The results proved that the constructed morphological filter was an appropriate tool for single sweep records of ERP.

• Journal of Engineering Education Research
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• v.15 no.4
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• pp.8-13
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• 2012

The Engineering school of Tohoku University has been offering a Team-based Engineering Design Course to its first year students since 1996 in order to increase the level of both motivation and interest in engineering. Freshmen are required to select one of approximately 150 topics and do some research on this topic. This course also provides opportunities for students to participate in exchange programs with the University of Washington (UW) and the University of Science and Technology Beijing (USTB). In the Tohoku-UW exchange program, which began in 1999, between 10 and 25 students of Tohoku visit the UW annually to present the results of the subjects the school has appointed in advance in the Team-based Engineering Design Course. In the Tohoku-USTB exchange program, which began in 2007, about 15 students from each university participate in a one day meeting organized by the students themselves. They give a presentation on either the results of the subject they selected in the course, or on an engineering related topic both groups have agreed to in advance. In this paper, a detailed history, the objectives, a schedule and the budget in these unique exchange programs is introduced together with an outline of the course and its contribution to the engineering design education.

• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.253-259
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• 2012

The purpose of this study was to determine how smartphone use posture affects biomechanical variables and muscle activities. Eleven university students(age: $22.2{\pm}2.6$ yrs, height: $176.6{\pm}4.7$ cm, weight: $69.5{\pm}7.5$ kg) who have no musculoskeletal disorder were recruited as the subject according to having experience in using the smartphone for more than one year. Angular velocity, muscle activity, and thumb finger pressure were determined for each trial. For each dependent variable, a one-way analysis of variance (ANOVA) with repeated measures was performed to test if significant difference existed among different three conditions (p<.05). The result showed that rotational angular velocity of the first metacarpal were increased in DESK posture compared with STAND posture during SU phase. The average nEMG values of FDI(First dorsal interosseous) were less in SIT and DESK posture compared with STAND posture during SR phase. These indicated that smartphone postures may effect the thumb ROM(Range of motion) and muscle activity. This has led to suggestions of the need for further kinetic and EMG analyses to evaluate best assess and characterize with smartphone use.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.7
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• pp.142-149
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• 2009

The aim of this study was to identify both the mechanical and reflex properties associated with spasticity in hemiplegic patients. Ten hemiplegic patients were included in this study. Multiple pendulum tests were executed for each subject, and knee joint angle and EMG of Rectus Femoris muscle were measured. The neuromusculoskeletal system model was developed from generally accepted mechanism and identified through minimization of the error in the model-predicted pendulum trajectories. The identification was successful in terms of small error in simulated kinematics and high sensitivity and precision of simulated torque against EMG activity. The reflex threshold showed significant difference between different clinical scores (p<0.01) and significant negative correlation (r=-0.93) with the EMG duration. It is expected that the suggested method may help in understanding mechanisms underlying spasticity.