• Journal of Auto-vehicle Safety Association
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• v.16 no.1
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• pp.55-61
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• 2024

The advancement of autonomous driving technology is expected to transform cars beyond mere transportation into multifunctional spaces for relaxation and entertainment. As autonomous driving technology becomes more sophisticated, with no need for direct driver control, the interior space of vehicles is anticipated to be utilized for various purposes. Consequently, the importance of car seats, the component most frequently interacted with by passengers during travel, is expected to significantly rise. However, existing car seats are designed according to a seated posture, necessitating verification for passenger safety and seat structure considerations in the context of autonomous driving, where comfortable postures may differ. For these reasons, it is anticipated that the seats of future autonomous vehicles will evolve with the incorporation of additional safety and convenience features. In this study, a three-axis car simulator was employed to investigate seat angles for comfortable postures of passengers in autonomous driving scenarios. Representative postures were identified to enhance passenger convenience. Furthermore, functional design factors contributing to passenger comfort were applied to conduct seat design, seat structure, and collision analysis, with an analysis of the interrelationships among design factors.

• Physical Therapy Korea
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• v.11 no.3
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• pp.1-9
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• 2004

Most exercise for Patellofemoral pain syndrome (PFPS) has focused on selectively strengthening the vastus medialis oblique muscle (VMO). Although open chain knee extension exercises are effective for increasing overall quadriceps strength, they are not always indicated for PFPS rehabilitation. This study was designed to identify the effect of combined posture of lower extremity on Electromyographic (EMG) activity of the vastus lateralis muscle (VL) and VMO during static squat exercises. The subjects were twenty young adult males who had not experienced any knee injury and their Q-angle was within a normal range. They were asked to perform static squat exercises in five various postures using their lower extremities. The EMG activity of the VL and VMO were recorded in five exercises by surface electrodes and normalized by %MVC values derived from seated, isometric knee extensions. The normalized EMG activity levels (%MVC) of the VL and VMO for the five postures of the lower extremities were compared using one way ANOVA with repeated measures. Results of repeated measures of ANOVA's revealed that exercise 3 and exercise 5 produced significantly greater EMG activity of VMO/VL ratios than exercise 1 (p<.05). When the static squat exercise was combined with hip adduction and toes pointed outwardly, the EMG activity of VMO/VL rates was increased. The EMG activity of VMO/VL ratio was highest during static squat exercises performed on a decline squat. These results haveimportant implications for progressive and selective VMO muscle strengthening exercises in PFPS patients.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.129.2-129
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• 2001

Visual effects are important cues for providing occupant s with virtual reality in a vehicle simulator which imitates real driving. The viewpoint of an occupant is sensitively dependent upon the occupant´s posture, therefore, the total body motion must be considered in a graphic simulator. A real time simulation is required for the dynamic analysis of complex human body motion. This study attempts to apply a neural network to the motion analysis in various driving situations. A full car of medium-sized vehicles was selected and modeled, and then analyzed using ADAMS in such driving conditions as bump-pass and acceleration. A multibody system analysis software, MADYMO, was used in the motion analysis of an adult male dummy in the seated position. Position data of the head were collected as inputs to the viewpoint movement. Based on these data, a back- propagation neural network was ...

• Journal of International Academy of Physical Therapy Research
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• v.9 no.3
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• pp.1533-1536
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• 2018

The purpose of present study was to investigate the effect of kinesio taping on pulmonary function in stroke patients using manual wheelchairs. Twenty stroke patients were divided into a wood chair group (WCG, n=10), a wheelchairs group (WG, n=10), and a kinesio taping with wheelchairs group (KWG, n=10). Taping with wheelchairs group was applied kinesio taping on back muscles (vertical paraspinal strips and oblique strips). All three groups were trained in upright seated posture for 30 minutes. Pulmonary function tests were performed with forced expiratory volume in one second, forced vital capacity and peak expiratory flow as spirometer. There was a significant increase in forced expiratory volume in one second and forced vital capacity only in KWG. The results of this study demonstrate that kinesio taping has an immediate effect on the improvement of pulmonary function in stroke patients using manual wheelchairs.

• Journal of Biomedical Engineering Research
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• v.32 no.1
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• pp.7-14
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• 2011

This study suggested an optimized algorithm for detecting the loss of balance(LOB) in the seated position. And the sensitivity analysis was performed in order to identify the role of each design variable in the algorithm. The LOB algorithm consisted of data processing of measured signals, an internal model of the central nervous system and a control error anomaly(CEA) detector. This study optimized design variables of a CEA detector to obtain improved values of the success rate(SR) of detecting the LOB and the margin time(MT) provided for preventing the falling. Nine healthy adult volunteers were involved in the experiments. All the subjects were asked to balance their body in a predescribed seated posture with the rear legs of a four-legged wooden chair. The ground reaction force from the right leg was measured from the force plate while the accelerations of the chair and the head were measured from a couple of piezoelectric accelerometers. The measured data were processed to predict the LOB using a detection algorithm. Variables S2, h2 and hd are related to the detector: S2 represents a data selecting window, h2 a time shift and hd an operating period of the LOB detection algorithm. S2 was varied from 0.1 to 10 sec with an increment of 0.1 sec, and both h2 and hd were varied from 0.01 to 1.0 sec with an increment of 0.01 sec. It was found that the SR and MT were increased by up to 9.7% and 0.497 sec comparing with the previously published case when the values of S2, h2 and hd were set to 4.5, 0.3 and 0.2 sec, respectively. Also the results of sensitivity analysis showed that S2 and h2 had considerable influence on the SR while these variables were not so sensitive to the MT.

• Journal of the Ergonomics Society of Korea
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• v.33 no.2
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• pp.135-142
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• 2014

Objective: This study aims to develop a new desk with a built-in bookholder and desktop-mounted sliding drawer for reducing stress of seated reading postures and to analyze its effect. Background: It is general for readers to bend their back and neck when reading books on desks, which may result in high back and neck postural stress. In addition, postures using vertically layered drawers positioned at the side of users may be awkward. Method: For reducing the postural stress, a new desk with a built-in bookholder and sliding drawer was developed based on a standard of KS G 4208 for student desk. The muscle activities of reading postures on both existing and new desks were measured using EMG, in which seven male and three female college students participated. The postural stress, and musculoskeletal discomfort and ease of usage for existing and new drawers were analyzed by RULA and questionnaire survey, respectively. Results: Compared to existing desk, the muscle activity for the new desk with a bookholder was reduced by 47% when reading books. In addition, musculoskeletal discomforts in the shoulder, neck and low back were significantly lower when using the new desk with a bookholder. Although the stresses for postures using the desktop-mounted sliding drawer and general drawer were not significantly different, the questionnaire survey revealed that the new desktop-mounted sliding drawer is easier to use. Conclusion: A new desk developed in this study significantly reduced postural stress and enhanced subjective preference when reading. Application: This would be useful when developing new desks with low postural stress.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.969-975
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• 2002

Visual effects are important cues for providing occupants with virtual reality in a vehicle simulator which imitates real driving. The viewpoint of an occupant is sensitively dependent upon the occupant's posture, therefore, the total human body motion must be considered in a graphic simulator. A real-time simulation is required for the dynamic analysis of complex human body motion. This study attempts to apply a neural network to the motion analysis in various driving situations. A full car of medium-sized vehicles was selected and modeled, and then analyzed using ADAMS in such driving conditions as bump-pass and lane-change for acquiring the accelerations of chassis of the vehicle model. A hybrid III 50%ile adult male dummy model was selected and modeled in an ellipsoid model. Multibody system analysis software, MADYMO, was used in the motion analysis of an occupant model in the seated position under the acceleration field of the vehicle model. Acceleration data of the head were collected as inputs to the viewpoint movement. Based on these data, a back-propagation neural network was composed to perform the real-time analysis of occupant motions under specified driving conditions and validated output of the composed neural network with MADYMO result in arbitrary driving scenario.

• Child Health Nursing Research
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• v.17 no.3
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• pp.167-173
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• 2011

Purpose: This study was conducted to compare the postural habits, body image, and peer attachment of adolescents with idiopathic scoliosis and healthy adolescents, and to examine the correlation between body image and peer attachment in each group. Methods: Eighty-three adolescents with idiopathic scoliosis and 83 healthy adolescents were recruited from 4 middle schools located in W city. Data were collected from November 22 to December 6 2010 using a structured questionnaire including items about postural habits, body image, and peer attachment. Data were analyzed using descriptive statistics, $X^2$-test, independent t-test and Pearson Correlation Coefficient. Results: Compared to healthy adolescents, adolescents with idiopathic scoliosis were more likely to use one hand, to lean back while seated, and to put weight on one leg while standing. The score for body image was significantly lower for adolescents with idiopathic scoliosis compared to healthy adolescents, but peer attachment was not significantly different between the two groups. Body image was significantly correlated with peer attachment only for the adolescents with idiopathic scoliosis. Conclusion: Interventions to promote balanced postural habits in adolescents with idiopathic scoliosis are needed. Information on body image and peer attachment for these adolescents should also be considered when developing interventions.

• Korean Journal of Clinical Laboratory Science
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• v.42 no.2
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• pp.97-102
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• 2010

The two new female cases of Angelman syndrome (AS) were described, which diagnosed on the basis of clinical features (dysmorphic facial features, severe mental retardation with absent speech, peculiar jerky movements, ataxic gait and paroxysms of inappropriate laughter) and neurophysiological findings. Failure to detect the deletion of the long arm of chromosome 15 or the absence of epileptic seizure were not considered sufficient to exclude a diagnosis of AS. Feeding problems, developmental delay and early signs of ataxia, especially tremor on handling objects and unstable posture when seated, proved effective as the clinical markers for early diagnosis of AS. Most of the authors agreed about the existence of three main EEG patterns in AS which may appear in isolation or in various combinations in the same patient. The most frequently observed pattern in children has prolonged runs of high amplitude rhythmic 2-3 Hz activity predominantly over the frontal region with superimposed interictal epileptiform discharges. High amplitude rhythmic 4-6 Hz activity, prominent in the occipital regions, with spikes, which can be facilitated by eye closure, is often seen in children under the age of 12 years. The EEG findings are characteristic of AS when seen in the appropriate clinical context and can be helpful to identify AS patients at an early age when genetic counselling may be particularly important.

• Safety and Health at Work
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• v.8 no.4
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• pp.356-363
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• 2017

Background: The aim of this study was to investigate which physical and psychosocial work demands were associated with excellent work ability in individuals with neck pain, and to investigate age and sex differences in these associations. Methods: The study sample was obtained from the Statistics Sweden cross-sectional Work Environment survey and consisted of workers who reported neck pain after work (N = 3,212). Results: The findings showed an association between excellent work ability and self-reported low exposure to lifting, twisted work posture, working with hands in shoulder level or higher, and leaning forward without support and combination of exposures containing these work demands. Low exposure to seated work and high demands showed a reversed association. The associations were present mainly among older workers and were generally stronger for men than for women. Conclusion: This study indicates that a lower level of physically demanding work is an important element to maintain excellent work ability, especially for the older worker with neck pain.