• 한국구조물진단유지관리공학회 논문집
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• 제6권1호
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• pp.193-203
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• 2002

The results of an experimental study on Saemangeum dredged sands are presented. Undrained triaxial compression tests were performed with there different initial relative densities, namely 18, 34, and 50%, intend to evaluate undrained Behavior. All undrained triaxial compression tests were performed under static loading conditions. Undrained triaxial compression tests were exhibited complete static liquefaction, zero effective confining pressure and zero stress difference at lower confining pressures. As confining pressures were increased, the effective stress paths indicated increasing resistance to static liquefaction by showing increasing dilatant tendencies. The fines and larger particles create a particle structure with high compressibility at lower confining pressure. The effect of increasing relative density was to increase the resistance of the sand against static liquefaction by making the sand more dilatant.

• Wind and Structures
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• 제7권6호
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• pp.359-372
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• 2004

Wind tunnel model studies were carried out to determine the wind load distribution on tributary areas near the gable-end of large, low-rise buildings with high pitch planar and curved roof shapes. Background pressure fluctuations on each tributary area are described by a series of uncorrelated modes given by the eigenvectors of the force covariance matrix. Analysis of eigenvalues shows that the dominant first mode contributes around 40% to the fluctuating pressures, and the eigenvector mode-shape generally follows the mean pressure distribution. The first mode contributes significantly to the fluctuating load effect, when its influence line is similar to the mode-shape. For such cases, the effective static pressure distribution closely follows the mean pressure distribution on the tributary area, and the quasi-static method would provide a good estimate of peak load effects.

• Journal of Advanced Marine Engineering and Technology
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• 제30권1호
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• pp.65-72
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• 2006

Heat transfer augmentation in heat exchangers has received much attention in recent years, mainly due to energy efficiency and environmental considerations. Many active and Passive techniques are currently being employed in heat exchangers, with some inserts providing a cost-effective and efficient means of augmenting heat transfer. The Purpose of this paper is to determine the pressure loss and heat transfer characteristics of a heat exchanger using static mixing technology. Experimental measurements were taken on two set-ups: a single tube heat exchanger and a shell-tube heat exchanger with two static mixing inserts. It was concluded that the static mixing inserts resulted in an increase in the pressure loss and heat transfer characteristics as can be expected.

• International Journal of Internet, Broadcasting and Communication
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• 제11권4호
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• pp.11-17
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• 2019

Plantar pressure data can be used not only for walking patterns in daily life, but also for eating, health care, and disease prevention. For this reason, the importance of plantar pressure measurement has recently increased. However, most systems that can measure both static and dynamic plantar pressure at the same time are expensive, not portable, and not universal. In this study, we propose a system that effectively reduces the number of sensors in plantar pressure system. Through this, we want to increase the economics and practicality by reducing the size and weight of the system, as well as the power consumption. First, for static plantar pressure and dynamic plantar pressure, the values measured by existing precision instruments are analyzed to determine how many measurement parts the insole is divided into. Next, for the divided measuring parts, the position of the sensor is determined by calculating the Center of Pressure (COP) for each part with the values of all dynamic and static plantar pressure sensors. Finally, in order to construct a personalized plantar pressure measurement system, we propose a weighting method for the static plantar pressure COP and the dynamic plantar pressure COP for each part.

• 유공압시스템학회논문집
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• 제8권2호
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• pp.17-22
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• 2011

The analysis of an air spring characteristics is necessary to design and control automotive air suspension system properly. A mathematical model of an air spring was derived in light of energy conservation first. Then static and dynamic experiments of the air spring have been fulfilled. The static stiffness with various initial pressures and effective areas were obtained from the static experimental results. Theoretical static stiffness obtained by using the mathematical model and effective area data is in close accordance with the experimental estimation. The dynamic experimental results show that the hysteresis in displacement-force cycle decreases when the frequency of the harmonic displacement excitation signal increases, but it does not change too much as the frequency is higher than 1Hz. And the dynamic stiffness goes up with increasing of the initial pressure and the excitation frequency.

• 대한물리치료과학회지
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• 제18권4호
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• pp.59-64
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• 2011

Purpose : The purpose of this study was to evaluate the effects of the stretching of the calf muscles on foot pressure and contact area in young adult. Participants stood on a wedge board that was sloped between 15~25 degree for 15min. After stretching participants stood quietly on force plate, result was recorded. Participants stood on a force plate for 1 min in eye closed condition, and them the foot pressure and area was recorded. The following variables were calculated off-line: anterior and posterior foot pressure and contact area, medial and lateral foot pressure and contact area. Results showed that anterior pressure change due to stretch, but mediolateral was not significant. This result suggested that stretching of the calf muscle has the effect of increasing anterior pressure by flexibility change on calf muscle, so this effects might be effective intervention for reduce of serious problem to neurologic patients in therapy session.

• 한국운동역학회지
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• 제26권3호
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• pp.285-292
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• 2016

Objective: This study collected data on muscle fatigue and ground reaction force during walking to provide a basis for development of custom-fitted outdoor walking shoes. The study analyzed an upright body exercise program using spine stabilization technique to determine the effect on foot plantar pressure in archers, demonstrate the effectiveness of upright body exercise, and develop a new, effective, and efficient training program. Method: A 12-week upright body exercise program was evaluated for the effect on plantar pressure in archers. Ten prize-winning archers (3 men, 7 women) in B metropolitan city, each with ${\geq}10years$ of experience, were given an explanation of the content and purpose of the program, and provided informed consent. Upright body exercise was performed 3 times a week for 12 weeks. A resistive pressure sensor was used to measure foot plantar pressure distribution and analyze quantitative information on variation in postural stability and weight shifting in dynamic balance during shooting, as well as plantar pressure in static balance with the eyes open and closed. Results: There were no significant differences in foot plantar pressure before and after participation in the exercise program. There was no statistically significant difference in foot plantar pressure in static balance with the eyes open or closed, or in foot plantar pressure in dynamic balance during shooting. Conclusion: An upright body exercise program had positive effects on foot plantar pressure in static and dynamic balance in archers by reducing body sway and physical imbalance during shooting and with eyes closed. This program is expected to help archers improve their posture and psychological state, and thereby improve performance.

• 대한정형도수물리치료학회지
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• 제23권2호
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• pp.27-32
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• 2017

Background: The purpose of this study was to compare the effects of IASTM and static stretching techniques on ankle joint range of motion (ROM), static foot pressure. Methods: Twenty four subjects with gastrocnemius shortness participated in this study. The subjects were assigned randomly to one of two groups: The soft tissue mobilization technique (IASTM) group received intervention using a IASTM instrument for two minutes, and the stactic stretching group performed self stretching for 30 seconds, four times. The ROM of the ankle joint was measured by active ankle dorsi-flexion test, and a TPScan was utilized to collect the plantar foot pressure. This experiment was performed by two physical therapists. The significant level was set at ${\alpha}=.05$. Results: The results were as follows: 1) The ROM of the ankle joint and was significantly increased in both groups. 2) Plantar foot pressure was no significant in both groups. 3) There were no significant differences between the IASTM group and static stretching group for any variable. Conclusions: The results of this study suggest that static stretching is an effective and easy technique for restoring proper muscle length in subjects with gastrocnemius shortness. We recommend that static stretching technique be used for treat gastrocnemius shortness in clinical setting and home program.

• 대한정형도수물리치료학회지
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• 제28권1호
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• pp.61-69
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• 2022

Background: This study aimed to investigate the effect of maitland mobilization and mobilization with movement (MWM) applied to the ankle joint on ankle dorsiflexion range of motion (ROM), static and dynamic balance, plantar pressure, and gait ability. Methods: A total of 24 individuals were assigned to either the maitland mobilization group (n=12) or the MWM group (n=12). Dorsiflexion ROM, static and dynamic balance, plantar pressure, 10-meter walk test were measured before and 4 weeks after the intervention. Results: Both groups showed a significant difference in the evaluation after 4 weeks as the dorsiflexion ROM of the ankle increased (p<.05), and the sway length and sway area indicating static balance decreased (p<.05). Furthermore, the movement area showing dynamic balance showed a significant increase (p<.05), the plantar pressure difference between both feet significantly decreased (p<.05). In the 10-meter walk test, there was a significant difference as the time decreased (p<.05). However, no significant difference between the two groups was observed (p>.05). Conclusion: According to the results of this study where, maitland mobilization and MWM were applied to the ankle joint of hemiplegic patients for 4 weeks, we found no difference between the two groups. However, each technique was found to be effective for dorsiflexion ROM, static and dynamic balance, plantar pressure, and gait.

• 동력기계공학회지
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• 제19권1호
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• pp.19-23
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• 2015

The swirling flow fields of a gun-type gas burner(GTGB) without a combustion chamber were measured by a straight-type five-hole pressure probe(FHPP) under the cold flow condition. The three kinds of velocity components and the static pressure were calculated by using a non-nulling calibration method covering the velocity reduction performance of the effective flow attack angle of ${\pm}80^{\circ}$. As a result, the velocity and static pressure measured by a FHPP comparatively shows the better performance on the swirling flow of a GTGB than those measured by X-probe.