• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.12
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• pp.961-967
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• 2009

A 3-dimensional numerical investigation of a WIG effect vehicle with DUP (direct underside pressurization) is performed to predict aerodynamic characteristics and the static height stability. DUP can considerably reduce take-off speed and minimize the hump drag while the vehicle accelerates on the water to take off. The DUP of the model vehicle, Aircat, consists of a propeller in the middle of the fuselage and an air chamber under the fuselage. The air accelerated by the propeller comes into the camber through the channel in the middle of fuselage and augments lift by changing its dynamic pressure to static pressure dramatically. However, the air accelerated by a propeller produces excessive drag and reduces static height stability.

• The Journal of Korean Academy of Sensory Integration
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• v.3 no.1
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• pp.57-65
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• 2005

Objective : The purpose of this study was to investigate the effect of sensory stimulation for static balance on normal children. Sensory input was consisted of colors, and music tempo stimulation. Methods : Participants were consisted of 20 normal kindergarten children ranging in age from six to seven years. The static balance was tested by a BPM(Balance Performance Monitor). In this study one-way ANOVA was used and the statistical significance level of results was determined at 0.05. Results : 1. According to color stimulation, there was no significant difference in static balance among red, yellow, green(p>0.05). 2. According to music tempo stimulation, there was no significant difference in static balance, among the high music tempo and low music tempo children in a general environment(p>0.05). 3. However, both green color and low music tempo stimulation have a little effect on static balance on normal children. Conclusion : These results indicate the possibility that the application method of green color and low music tempo stimulation may help in the improvement of static balance for the disabled children. This study will be used as the foundational data of therapeutic environment for the disabled children.

• Journal of Biosystems Engineering
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• v.20 no.4
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• pp.360-367
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• 1995

The effect of air vent holes, stacking methods of boxes and clearance between boxes on static pressure drop, were measured to design of pressure cooling system. Static pressure drops in air vent hole of carton box were measured for different hole opening ratio from 1% to 5%. Static pressure drop was expressed as a function of superficial velocity as second-degree polynomial. At given static pressure in plenum chamber, static pressure drop in boxes was shown as second-degree polynomial of the number of carton box in series stacking method, as first-degree polynomial in height and parallel stacking method. In pressure cooling of 24 boxes of Tsugaru apple, air flow rates through clearance between the boxes were shown 1.27 and 1.65 times than those of through the inside of boxes at the plenum pressure of 10mmAq and 20mmAq, respectively.

• Journal of International Academy of Physical Therapy Research
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• v.12 no.2
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• pp.2354-2358
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• 2021

Background: Stroke is a neurological disorder characterized by an impaired static balance. A change in poor posture after stroke may worsen static balance. The balance control through an upright posture may include kinesiology taping of the middle back. Objectives: To investigated the effect of kinesiology taping of middle back on static balance in patients with stroke. Design: A randomized controlled trial. Methods: A total of 10 patients with stroke were divided into two groups. The experimental and control groups received kinesiology taping and placebo taping of the middle back, respectively. After 24 h, static balance (i.e., sway area and path length) was measured in closed eyes condition. Results: The experimental group (kinesiology taping group) showed a significant decrease in sway area and path length after the intervention. In addition, kinesiology taping group showed a significant decrease in sway area and path length compared to the control group. Conclusion: Kinesiology taping of the middle back can improve static balance in stroke patients.

• Steel and Composite Structures
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• v.24 no.5
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• pp.615-633
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• 2017

Fatigue crack initiated in welded tubular joints due to cyclic loading may produce harmful effect on the integrity of the tubular structures. To study such effect, both fatigue and static tests on nine circular tubular T-joint specimens made of carbon steel materials were carried out. The specimens were subjected to tensile loading in both fatigue and static tests. The load-displacement relation, the crack propagation and the failure mode of the specimens are all analyzed. The deterioration of the static strength of the cracked T-joints is also investigated and evaluated through an area reduction factor. Experimental results indicate that the static strength of a tubular T-joint with a surface crack seems to decrease slightly while a through crack has relatively remarkable effect on the reduction of the static strength. Additionally, experimental results also show that the toughness of the materials and the geometry of the specimens play an important role on the failure process of cracked tubular T-joints.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.739-744
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• 2001

The concrete bridge deck is quitely required to be replaced or strengthened due to decreasing load carrying capacity. In this study, to increase load capacity of the reinforced concrete slab, bridge deck is reinforced with the glass fiber sheets. they are examined on the strengthen effect and the static behavior, This paper considers relation of load-displacement and strain-distance. The static behavior of the slab strengthened is represented to maximum load. Owing to that, they are examined on increasing load carrying capacity of reinforced bridge deck and strengthen effect about on the crack.

• Advances in concrete construction
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• v.7 no.2
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• pp.97-105
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• 2019

In this paper, the workability and static stability were evaluated using a proposed test method. Workability and static stability represent a key property of self-compacting concrete (SCC) in fresh state. A number of standardized test methods were developed to assess these properties. However, no accelerated test method reliably predicts both workability and static stability of SCC. In the present work, a modified K-slump test method was developed to evaluate workability and static stability of SCC. In order to take implicit mixture variations of SCC constituents that can affect fresh SCC properties, a central composite design was adopted to highlight the effect of gravel to sand ratio (G/S), gravel 3/8 to gravel 8/15 ratio (G1/G2), water to cement ratio (W/C), marble powder to cement ratio (MP/C) and superplasticizer content (SP) on workability measured with slump and flow time (T50) tests and static stability measured with sieve stability test (Pi), segregation test index (SSI), Penetration test (Pd) and the proposed K-slump test (Km). The obtained results show that G/S ratio close to 1 and G1/G2 ratio close to 60% can be considered as optimal values to achieve a good workability while ensuring a sufficient static stability of SCC. Acceptable relationships were obtained between Slump flow, Pi, Pd and Km. Results show that the proposed K-slump test allow to assess both workability and static stability of fresh SCC mixtures.

• Geophysics and Geophysical Exploration
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• v.27 no.3
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• pp.181-195
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• 2024

This tutorial explains that the static effect in the magnetotelluric (MT) survey is a physical phenomenon caused by charges accumulated on the boundaries of subsurface inhomogeneities. To facilitate understanding of the physical phenomenon, differences between static induction and charge accumulation on the boundary are explained and analyzed with help of schematic illustrations. Subsequently, from the electromagnetic (EM) integral equation formulation, it is clearly shown that the secondary electric field due to charges accumulated on the interface in the presence of the primary field appears as the static effect. Therefore, except in the cases of the layered earth or a two-dimensional earth with transverse magnetic (TM) mode excitation, the static effect always exists in MT responses and further, it is not 'static' but rather frequency dependent. Despite the fact that the static effect is a secondary electric field due to inhomogeneity, inevitable under-sampling in the frequency and spatial domains prevent the effect from being handled properly in numerical inversion. Therefore, considering the practical aspects of the MT survey, which cannot be a continuous measurement covering the entire survey area over a wide frequency band, a three-dimensional (3-D) inversion incorporating the static shift as a constraint with the Gaussian distribution is introduced. To enhance understanding of the integral equation EM modeling, the formulation of the 3-D integral equation and mathematical analyses of the Green tensor and scattering current are described in detail in the Appendix.

• Korean Chemical Engineering Research
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• v.48 no.5
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• pp.638-642
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• 2010

In order to develope anti - static polyester resin which may be employed to dangerous circumstance with high organic vapor content, the effect of anti - static agents on the surface resistance and tensile strength of polyester resin were studied. Three organic anti - static agents and a conductive carbon black were adapted and used separately and together. The effects of anti - static agents, their contents, and synergic effect of anti - static agents were experimentally examined. Surface resistance and tensile strength of the polyester resin were decreased with the content of anti - static agents, and polyester resin with low surface resistance and relatively high tensile strength could be prepared by synergic effect of organic anti - static agent and carbon black.

• Physical Therapy Korea
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• v.10 no.3
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• pp.1-15
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• 2003

The purpose of this study was to assess the effect of visual block (eyes open or closed), mental task type, and participation in an exercise program on static balance in the elderly. The subjects were 34 elderly (>65 years old) residents of a social welfare institute in Gyeonggi-do. We measured the following variables. Berg balance scale, mini mental state examination, balance performance monitor (sway area, path, and maximal sway velocity), age, weight, height and whether the subject participated in an exercise program. Scores for the Berg balance scale and mini mental state examination were evaluated to assess static balance ability either alone (single task paradigm) or while performing a mental task (dual task paradigm). Static balance variables that were measured included sway area, path, and maximal sway velocity. Each test was repeated three times. Multiple regressions analysis was used to examine the effect of each variable on static balance ability. For the dual task paradigm, static balance was affected by whether the subject participated in an exercise program. The Berg balance scale score for subjects with their eyes open was affected by whether they participated in an exercise program, while this variable in addition to the height and weight of subjects were determining variables in subjects with their eyes closed. As a result, whether subjects participated in an exercise program affected their static balance irrespective of whether their eyes open or closed. Therefore, regular exercise is recommended for elderly people and further research is needed to examine the relationship between static and dynamic balance while performing mental tasks such as cognition and attention.