• Journal of the Korean Wood Science and Technology
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• v.11 no.3
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• pp.14-22
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• 1983

The purpose of this study was to evaluate the effect of short-term paraquat treatment without insecticides on the enhancement in oleoresin of pitch pine (Pinus rigida M.) at various distances from the wound height. The trees were treated with 0.5, 2 and 4% paraquat solutions using the bore-hole technique. Duplicate cores from treated and untreated sides of treated trees were made at 5 height levels (-0.3, 0.0, 0.3, 0.9 and 1.5 m above the wound height) at 3 months after treatment. The alcohol-benzene extractives based on unextracted oven-dry cores were taken as oleoresin contents. The results were as follows: 1. The effect of oleoresin enhancement at wound height were not affected by paraquat concentration. 2. Ascending distance of the enhancing effects above the wound height was directly related to paraquat concentration. Only in 4% paraquat treated trees, the effect extended to 1.5 m above the wound height. 3. As a result of examining descending distance of the enhancing effects at 0.3 m below the wound height, the effects extended to there in 4% and 2% paraquat treated trees.

• 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.

• International Journal of Highway Engineering
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• v.18 no.5
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• pp.31-37
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• 2016

PURPOSES : The purpose of this study is to evaluate the effect of the quiet pavement on reducing a barrier height by using a prediction tool called SoundPLAN. METHODS : Firstly, the prediction was carried out to evaluate the difference in the maximum noise level at a building facade between the normal and the quiet pavements without a barrier. After calculating the noise reduction effect by the quiet pavement, a comparable barrier height to obtain the same noise reduction effect with it was predicted according to designable factors including road-building distance(10 m, 20 m, 40 m) and road-barrier distance(5 m, 10 m, 20 m, 30 m). RESULTS : The result showed that within the considered designable factors, the maximum barrier height was 37 m, 52 m, and 55 m to have the same noise reduction effect by the quiet pavement reducing 1 dBA, 3 dBA, and 5 dBA, respectively. It was evaluated that the barrier height increased with the increase of the road-building and road-barrier distances. To simulate the real situation in urban areas and to evaluate the combined effect of the normal/quiet pavement and barrier, the barrier height was fixed as 6 m. It was predicted that the noise level would reduce to as low as 0.2 dBA by the combination of normal pavement and barrier. On the other hand, the combination of the quiet pavement and barrier reduced 1.2 dBA, 3.2 dBA, and 5.2 dBA, respectively, for quiet pavement reducing 1 dBA, 3 dBA, and 5 dBA. CONCLUSIONS : A guideline needs to be suggested to select appropriate noise abatement schemes by considering factors such as the roadbuilding and road-barrier distances.

• Structural Engineering and Mechanics
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• v.41 no.2
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• pp.299-312
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• 2012

Stiffened coupled shear walls (SCSW) are under axial load resulting from their weight and this axial load affects the behavior of walls because of their excessive height. In this paper, based on the continuum approach, the optimal position of the stiffening beam on the stiffened coupled shear walls is investigated considering the effect of uniformly distributed axial loads. Moreover, the effect of the height of stiffened coupled shear walls on the optimal position of the stiffening beam has been studied with and without considering the axial force effect. A computer program has been developed in MATLAB and numerical examples have been solved to demonstrate the reliability of this method. The effects of the various flexural rigidities of the stiffening beam on the internal forces and the lateral deflection of the structure considering axial force effect have also been investigated.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.6
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• pp.479-484
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• 2009

The effect of anode gas channel height on gas diffusion and cell performance in a 100 $cm^2$ class molten carbonate single cell is investigated. Single cell separators with three different channel height are used. The effect of the gas channel height on the distribution of the reactive gas concentration is evaluated by the two-dimensional concentration diffusion equation. The overpotential caused by concentration drop with different channel height is estimated by the voltage decay related to diffusion of reactants, well known as concentration polarization, using limiting current density. The estimation could have the possibility to identify the reactant mass transfer polarization in the complicate factors of the overall electrodes.

• Earthquakes and Structures
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• v.8 no.3
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• pp.779-799
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• 2015

The slosh height and the possibility of water spill from rectangular Spent Fuel Storage Bays (SFSB) and Tray Loading Bays (TLB) of Nuclear power plant (NPP) are studied during 0.2 g, Safe Shutdown Earthquake (SSE) level of earthquake. The slosh height obtained through Computational Fluid dynamics (CFD) is compared the values given by TID-7024 (Housner 1963) and American concrete institute (ACI) seismic codes. An equivalent amplitude method is used to compute the slosh height through CFD. Numerically computed slosh height for first mode of vibration is found to be in agreement the codal values. The combined effect in longitudinal and lateral directions are studied separately, and found that the slosh height is increased by 24.3% and 38.9% along length and width directions respectively. There is no liquid spillage under SSE level of earthquake data in SFSB and TLB at convective level and at free surface acceleration data. Since seismic design codes do not have guidelines for combined excitations and effect of higher modes for irregular geometries, this CFD procedure can be opted for any geometries to study effect of higher modes and combined three directional excitations.

• The Journal of Pediatrics of Korean Medicine
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• v.25 no.1
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• pp.119-127
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• 2011

Objectives: The purpose of this study is to evaluate the parents' awareness on the oriental medical treatment and their expectation on children's growth. Methods: The survey was conducted on 78 Health Kids Fair visitors, and 87 children's height and weight were measured in this study. Results: 1. Compare to other treatment, 62.82% of the parents responded that herbal medicine is relatively effective in treating weakness, followed by 'Allergic disease'(46.15%) 'Growth disturbance'(26.92%) 'Obesity'(26.92%) 'Respiratory disease'(26.92%) 'Digestive disease'(19.23%) 'Precocious puberty'(8.97%) 'Neurologic & psychologic disease'(6.41%) 'Urogenital disease'(3.85%). 2. Parents recognize that 'Oriental medicine have an effect on children's height mostly'(25.64%) 'Oriental medicine have an effect on children's height partially'(64.10%) 'Oriental medicine have no effect on children's height'(10.26%) 25.64% of the parents responded that herbal medicine would be helpful in increasing height, 64.10% of the parents said they would be helpful to the certain extent, and 10.26% said they would not play any roles. 3. Expected average weight, height, and BMI score for the boys were 71.8kg, 179.6cm and 22.10. For the girls, however, they were 53.4kg, 168.7, and 18.74. 4. Survey on parents' awareness on benefits of different treatments for challenged growth, Herbal medicine'(48.72%) 'Acupuncture'(7.69%), 'Moxibustion'(3.85%), 'Electronic acupuncture and Aqua acupuncture'(1.28%), 'Massage on acupuncture point'(19.23%), 'Consultation of eating habits'(61.54%), 'Consultation of exercise'(47.44%) were measured. Conclusions: Considering the collected results, we realized that the parents' expected height on their children was, in fact, higher than the standard height. In addition, for treatments for their children's growth improvement, parents expected that 'Herbal madicine' 'Massage on acupuncture point' 'Consultation of eating habits' 'Consultation of exercise would be beneficial.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.605-613
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• 2003

In order to make use of the protection effect against wind by the vegetation, it examined whether it should make what vegetation form and arrangement using the 2-dimensional non-hydrostatic model. When the foliage shielding factor increases, it becomes hard to take in protection effect against wind in a residential section. When it makes height of vegetation high, it becomes hard to take in protection effect against wind with height. In the comparison in the case where vegetation high is gradually made low toward wind-stream from a vegetation, and the case of making it low gradually, although former tends to receive the protection effect against wind by the vegetation, attenuation of wind velicity becomes large. In the comparison in the case where foliage shielding factor and distribution of density of leaf are gathered gradually toward wind-stream from a vegetation. It has been understood to evaluate to height the influence that the vegetation multi-layer model by which the heat revenue and expenditure in the direction of the vegetation height is considered is used, and to characterize the vegetation group by the parameter setting.

• Earthquakes and Structures
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• v.25 no.2
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• pp.135-148
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• 2023

The structure-soil-structure interaction (SSSI) effect in adjacent structures may affect the liquefaction-induced damage of shallow foundation structures. The existing studies only analysed the independent effects on the structural dynamic response but ignored the coupling effect of height difference and distance of adjacent structures (F) on liquefied foundations on the dynamic response. Therefore, this paper adopts finite element and finite difference coupled dynamic analysis method to discuss the effect of the F on the seismic response of shallow foundation structures. The results show that the effect of the short structure on the acceleration response of the tall structure can be neglected as F increases when the height difference reaches 2 times the height of the short structure. The beneficial effect of SSSI on short structures is weakened under strong seismic excitations, and the effect of the increase of F on the settlement ratio gradually decreases, which causes a larger rotation hazard. When the distance is smaller than the foundation width, the short structure will exceed the rotation critical value and cause structural damage. When the distance is larger than the foundation width, the rotation angle is within the safe range (0.02 rad).

• Korean Journal of Applied Biomechanics
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• v.16 no.4
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• pp.31-38
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• 2006

The purpose of this study was to investigate the effect of changing the steps height on the joint moment of lower extremity in stair-descent activity of elderly persons. Data were collected by 3-D cinematography and force platform. 9 male elderly subjects in the 60s and 70s participated in this study. All subjects performed a stair-descent in four different heights of stairs (10, 14, 18, 22cm) having 5 step staircase. The results were as follows. 1. For the step height of 22cm the maximum. plantarflexion moment was the smallest and the largest for the step height of 14cm. 2. There was not a statistical difference shown for the extension moment of the knee joint for the different height of steps. 3. There was not a statistical difference shown for the flexion moment of the hip joint for the varying height of steps but on average for the 18cm step this increased rapidly. 4. The smallest maximum. value for inversion moment was revealed for the step height of 10cm and this increased significantly for the step height of 22cm. 5. The smallest maximum. value for abduction moment of the hip joint was revealed for the step height of 10cm and this increased significantly for the step height of 22cm. 6. There was no significant difference shown for the maximum. abduction moment for the hip joint. The main conclusion is that there is a huge difference in the moment of the lower extremities for the elderly while walking down a stairs with a step height above 18 cm and that this moment increased or decreased rapidly under a condition of step height being 22cm. With the results from this research and related research of elderly walking upstairs it can be shown that the step height has a large role in the safety for the elderly.