• The Research Journal of the Costume Culture
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• v.28 no.3
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• pp.299-312
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• 2020

The purpose of this study is to create a shirt sloper suitable for an elderly male body shape by producing virtual models using a 3D-virtualization program, making a torso prototype using the Yuka CAD system, and employing 3D simulation to virtualize and calibrate the model. First, the following three types of obese dummies are implemented through the CLO 3D program: Type 1 exhibits body fat in the lower body; Type 2 exhibits an obese abdomen; and Type 3 displays a balanced form of obesity. Second, for the design of the shirt pattern, the waist back length (measured value+1), back armhole depth (C/10+12+3+0.5~1.5), front armhole depth (back armhole depth 0~1), front interscye (2C/10-1+0.5-0.5), armscye depth (C/10+2+3.5+ 0.5), back interscye (2C/10-1+1), front chest C (C/4+2.5+1), back chest C (C/4+2.5-1), front hem C (C/4+2.5+1(+2)), back hem C (C/4+2.5-1(+2)), cap height (AH/3-5), and biceps width (Front AH-1, Back AH-1) are calculated. Third, the virtual attachment of the shirt pattern is resolved by increasing the front and back armhole depths, and the front and rear wrinkles are improved by adding a back armhole dart. The front hem lift and lateral pull caused by the protrusion of the abdomen are amended by increasing the margin of the chest, waist C, and hip C, with the appearance improved by balanced margin distribution in the front, back, and side panels. The improved retail pattern with an increase in the front armholes C was balanced on the torso plate.

• Wind and Structures
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• v.30 no.5
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• pp.533-546
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• 2020

Large Eddy Simulation (LES) is used to study the effects of steady slot suction on the aerodynamic forces of and flow around a wall-mounted finite-length square cylinder. The aspect ratio H/d of the tested cylinder is 5, where H and d are the cylinder height and width, respectively. The Reynolds number based on free-stream oncoming flow velocity U_∞ and d is 2.78×10⁴. The suction slot locates near the leading edge of the free end, with a width of 0.025d and a length of 0.9d. The suction coefficient Q (= U_s/U_∞) is varied as Q = 0, 1 and 3, where U_s is the velocity at the entrance of the suction slot. It is found that the free-end steady slot suction can effectively suppress the aerodynamic forces of the model. The maximum reduction of aerodynamic forces occurs at Q = 1, with the time-mean drag, fluctuating drag, and fluctuating lift reduced by 3.75%, 19.08%, 40.91%, respectively. For Q = 3, all aerodynamic forces are still smaller than those for Q = 0 (uncontrolled case), but obviously higher than those for Q = 1. The involved control mechanism is successfully revealed, based on the comparison of the flow around cylinder free end and the near wake for the three tested Q values.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.637-640
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• 2005

The mechanical properties of bellows, such as the extensibility and the strength can be changed depending on the shape. For the shipbuilding material, it is favorable that the fatigue lift is long due to the elastic property and the reduction of thermal stress in piping system. Nowadays, the domestic production and design of bellows are based on the E.J.M.A Code. Therefore, the design standard is in need because of much errors and lack of detailed analysis. In this study, it is attempted to find out the optimal shape of U-type ship's bellows that is applied to design of experiment using the finite element method. The effective factors, mountain height, length, thickness, and number of mountains and the length of joint are considered and the proper values are chosen for the simulation. The number of mountains are increased, the volume increases above the standard volume and the stress obviously increases. In addition, the effect of the thickness of bellows on the stress is very large. Both of the volume and stress are decreasing at a certain lower value region.

• Wind and Structures
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• v.29 no.1
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• pp.75-84
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• 2019

A steady slot suction near the free-end leading edge of a finite-length square cylinder was used to control its aerodynamic forces and vortex-induced vibration (VIV). The freestream oncoming flow velocity ($U_{\infty}$) was from 3.8 m/s to 12.8 m/s. The width of the tested cylinder d = 40 mm and aspect ratio H/d = 5, where H was the height of the cylinder. The corresponding Reynolds number was from 10,400 to 35,000. The tested suction ratio Q, defined as the ratio of suction velocity ($U_s$) at the slot over the oncoming flow velocity at which the strongest VIV occurs ($U_{\nu}$), ranged from 0 to 3. It was found that the free-end slot suction can effectively attenuate the VIV of a cantilevered square cylinder. In the experiments, the RMS value of the VIV amplitude reduced quickly with Q increasing from 0 to 1, then kept approximately constant for $Q{\geq}1$. The maximum reduction of the VIV occurs at Q = 1, with the vibration amplitude reduced by 92%, relative to the uncontrolled case. Moreover, the overall fluctuation lift of the finite-length square cylinder was also suppressed with the maximum reduction of 87%, which occurred at Q = 1. It was interesting to discover that the free-end shear flow was sensitive to the slot suction near the leading edge. The turbulent kinetic energy (TKE) of the flow over the free end was the highest at Q = 1, which may result in the strongest mixing between the high momentum free-end shear flow and the near wake.

• Wind and Structures
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• v.30 no.5
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• pp.525-532
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• 2020

This work numerically investigates the effects of Reynolds number Re_D (= 100 - 150), cross-sectional aspect ratio AR = ( 0.25 -1.0), and attack angle α (= 0° - 90°) on the forces, Strouhal number, and wake of an elliptical cylinder, where Re_D is based on the freestream velocity and cylinder cross-section height normal to the freestream flow, AR is the ratio of the minor axis to the major axis of the elliptical cylinder, and α is the angle between the cylinder major axis and the incoming flow. At Re_D = 100, two distinct wake structures are identified, namely 'Steady wake' (pattern I) and 'Karman wake followed by a steady wake (pattern II)' when AR and α are varied in the ranges specified. When Re_D is increased to 150, an additional wake pattern, 'Karman wake followed by secondary wake (pattern III)' materializes. Pattern I is characterized by two steady bubbles forming behind the cylinder. Pattern II features Karman vortex street immediately behind the cylinder, with the vortex street transmuting to two steady shear layers downstream. Inflection angle α_i = 32°, 37.5° and 45° are identified for AR = 0.25, 0.5 and 0.75, respectively, where the wake asymmetry is the greatest. The α_i effectively distinguishes the dependence on α and AR of force and vortex shedding frequency at either Re_D. In Pattern III, the Karman street forming behind the cylinder is modified to a secondary vortex street. At a given AR and α, Re_D = 150 renders higher fluctuating lift and Strouhal number than Re_D = 100.

• Journal of the Korean Geotechnical Society
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• v.19 no.1
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• pp.5-19
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• 2003

A series of centrifuge model tests were conducted to investigate the behavior of piled bridge abutments subjected to lateral soil movements induced by approach embankments. The effect of clay layer depth and the rate of embankment construction on piled bridge abutments are the main focus of this study. Tests were performed for two loading types: (1) incremental loading applied in six lifts to the final embankment height; (2) instant loading corresponding to the final embankment height applied in one lift quickly. A variety of instrumentations such as LVDTs, strain gauges, earth pressure transducers, and pore pressure transducers are installed in designed positions in order to clarify the soil-pile interaction and the short- and long-term behavior for piled bridge abutments adjacent to surcharge loads. Based on the results of a series of centrifuge model tests, the distribution of lateral flow induced by staged embankment construction has trapezoidal distribution. The maximum lateral soil pressure is about 0.75$\gamma$H at surcharge loading stage, and about 0.35 $\gamma$H at over 80% consolidated stage.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.240-246
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• 2009

Statement of problem: Insertion of endosseous implants in the atrophic maxilla is often complicated because of lack of supporting bone. Augmentation of the floor of the maxillary sinus with autogenous bone & bone substitute graft has been proven to be a reliable treatment modality, at least in the short term. The aim of this study is to evaluate the factors of implant survival rate associated with maxillary sinus lift with grafts. Material and methods: The sinus floor was augmented with bone grafts derived from modified Caldwell-luctechnique(71 subject, 93 sinus, 180 implants), the autogenous bone or autogenous+Bio-oss. Before implant installation the width and height of the alveolar crest were increased in the first stage procedure in 10 patients while in the other 61 patients augmentation and implant installation could be performed simultaneously width and height of the alveolar crest > 4 mm) or delayed installation. Results: In all case bone volume was sufficients for implant insertion. 14 of 180 inserted implants were lost during follow up and the healing period Patient received implant supported overdenture(5 patients) or fixed bridge(62 patients). Conclusion: Within the limit of the result of this study, we conclude that bone grafting of the floor of the maxillary sinus floor with bone for the insertion of implants might be a reliable treatment modality and the autogenous bone graft and delayed installation method might be the factors for good results.

• Aerospace Engineering and Technology
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• v.12 no.2
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• pp.99-107
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• 2013

Local dust storm and lifting to dust frequently occurs in Mars. But it is known to lift dust is associated with atmospheric circulation, the cause of dust lifting is not find yet. The height of dust storm is more than the Himalayas, and the large size dust storm covers half of hemisphere or hemisphere. The kind of dust storm is risk factor to land and to carry out a mission. In this paper, we carry out analysis on the season and place of dust storm, and construct a map with the place of dust storm. We expect that the season and place of dust storm are able to be predicted with being based on the results. And this paper can be utilized as preliminary for selection of landing site and time of launching and landing.

• Wind and Structures
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• v.34 no.4
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• pp.355-369
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• 2022

Section model test, as the most commonly used method to evaluate the aerostatic and aeroelastic performances of long-span bridges, may be carried out under different conditions of incoming wind speed, geometric scale and wind tunnel facilities, which may lead to potential Reynolds number (Re) effect, model scaling effect and wind tunnel scale effect, respectively. The Re effect and scale effect on aerostatic force coefficients and aeroelastic characteristics of streamlined bridge decks were investigated via 1:100 and 1:60 scale section model tests. The influence of auxiliary facilities was further investigated by comparative tests between a bare deck section and the deck section with auxiliary facilities. The force measurement results over a Re region from about 1×10⁵ to 4×10⁵ indicate that the drag coefficients of both deck sections show obvious Re effect, while the pitching moment coefficients have weak Re dependence. The lift coefficients of the smaller scale models have more significant Re effect. Comparative tests of different scale models under the same Re number indicate that the static force coefficients have obvious scale effect, which is even more prominent than the Re effect. Additionally, the scale effect induced by lower model length to wind tunnel height ratio may produce static force coefficients with smaller absolute values, which may be less conservative for structural design. The results with respect to flutter stability indicate that the aerodynamic-damping-related flutter derivatives 𝘈^*₂ and 𝐴^*₁𝐻^*₃ have opposite scale effect, which makes the overall scale effect on critical flutter wind speed greatly weakened. The most significant scale effect on critical flutter wind speed occurs at +3° wind angle of attack, which makes the small-scale section models give conservative predictions.

• Korean Journal of Construction Engineering and Management
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• v.15 no.6
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• pp.53-62
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• 2014

Recently, the number of super high-rise building projects have been increased after recovering from international financial crisis. In super high-rise building project, vertical lifting is critical to overall project productivity, due to its limited lifting equipments. Also for projects which buildings' height are higher than 400m, transfer operation in lifting is inevitable because of lifts' maximum lifting height. In transfer operation, setting a transfer floor is essential for saving lifting time of resources. In this research, using discrete event simulation modeling with AnyLogic 7.0 software and metaheuristic optimization with OptQuest software, the method of optimizing a transfer floor for workers during the morning peak time is proposed. Comparing to the result of the case which transfer floor is designated to the middle floor, setting optimized transfer floor significantly decrease the total lifting time of workers. By using proposed simulation and optimization tool, saving budget and time through increasing available working hour is expected.