• International Journal of Advanced Culture Technology
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• v.9 no.1
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• pp.22-27
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• 2021

Morphology of contemporary city streets is composed of overlapping infrastructures corresponding to the new street within the established organization, contemporary system, future circumstance, and population. As well, two overlaid organizations and morphological, historical, social and physical development lead to sharp acute algle(triangular) site, and the architecture in this site has a restriction on the availability of the internal space and the external design due to outside shape sharpness. We want to have a positive effect on the internal and external design of the architecture in the future by categorization of the shape and processing characteristics of the acute angle corner of the trilateral site. The characteristics and design categorization shown in this case study are as follows. Constitution a unique and independent form, lead streets and shape a exclusive image of the landscape, alleviate sharpness by configuring a acute angle point as a plane, use void to give reserve character, replace roundness for companionability to induce ambience in the road, embrace the characteristics of the site and create internal spaces and functions, emphasize the characteristics of each stairs, retain of uniqueness and highlight the characteristics of a vertical elements.

• Korean Journal of Applied Biomechanics
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• v.20 no.4
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• pp.429-436
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• 2010

The purpose of this study was to analyze the kinematic factors and throwing variables for the 3-turn and 4-turn techniques and for release as well as to provide technical advice for improving athletic performance in hammer throwing. Data analysis led to the following conclusions: To increase the rotation speed for the 3-turn and 4-turn techniques, the time elapsed during the 1-foot support period should be decreased the distance between the rotating foot and the rotation axis should be small and the height of the hip joint should be increased at the times of release The throwing angle at the moment of release should be more than 40 degrees, and the throwing position should be taken vertically high at the shoulder joints. To accelerate the motion of the hammer, the speed should not be reduced during the 1-foot support period but should be increased during the 2-foot support period for much greater acceleration. In the 3-turn technique, the angles of the shoulder axis and hummer string should be dragged angle at the maximum point and lead angle at the minimum point, and dragged angle at the maximum and minimum points in the 4-turn at the time of relase The upper body should be quickly bent backward, the knee angle should be extended, and the angles of the shoulder axis and hammer string should be dragged angle close to 90 degrees.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.723-724
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• 2009

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.07a
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• pp.691-694
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• 2021

The malalignment of the trunk causes abnormal stress in a specific area and lead to trunk instability. The purpose of this study was to investigate the correlation between the angle between the infrasternal angle and the trunk side shift distance. The participants in this study 22 subjects were participated. The infrasternal angle and trunk side shift distance were measured using a camera and analyzed using the Image J program. The correlation between the asymmetry of the infrasternal angle and trunk side shift distance was moderate (r=-0.413; p=0.028). According to the asymmetry of the infrasternal angle, it was confirmed that trunk lateral shift appeared in a specific direction. Based on result, it suggests that infrasternal angle and trunk side shift should be considered in the intervention plan of patients with asymmetry of the infrasternal angle.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.1081-1090
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• 2024

The liquid Lead-bismuth eutectic is used as the coolant for Gen-IV reactor concepts. However, due to its strong corrosive and high operating temperature, it is difficult to accurately measure the flow rate in long-term operating conditions. Venturi flowmeter is a simple structured flowmeter, which plays a very important role in the flow measurement of high-temperature liquid metals, especially since the existing flowmeters are difficult to be competent. It has the advantages of easy maintenance and stable operation. Therefore, it is necessary to study the operating conditions of the venturi flowmeter under high-temperature conditions. This work performs a series of simulations of the fluid-solid interaction between the flow liquid metal and venturi flowmeter with COMSOL software, including the dimensional sensitivity analysis of the venturi flowmeter to explore the most suitable structure and parameters for liquid heavy metal, the sensitivity analysis of the geometric parameters of the venturi tube on the varying conditions. It shows that when the contraction angle of the venturi flowmeter is 33°, the diffusion angle is 13°, the diameter of the throat is 8 mm, and the temperature of the lead-bismuth eutectic is 733.15 K, it is most suitable for the measurement in the lead-bismuth circuit.

• IEIE Transactions on Smart Processing and Computing
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• v.2 no.5
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• pp.310-316
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• 2013

This paper reports a sinusoidal $180^{\circ}$ drive for a permanent magnet (PM) brushless motor employing automatic angle compensator to suppress the driving loss during the wide-range load operation. The proposed drive of the sinusoidal $180^{\circ}$ PM Brushless motor reduced the amplitude of the 3-phase current by compensating for the lead-angle of the fundamental waves of the 3-phase PWM signal. The conventional lead-angle method was implemented using the fixed angle or memorized table, whereas the proposed method was automatically compensated by calculating the angle of the current and voltage signal. The algorithm of the proposed method was verified in a 30 W PM brushless motor system using a PSIM simulator. The efficiency of the conventional method was decreased 90 % to 60 %, whereas that of proposed method maintained approximately 85 % when the load shift was 0 to $0.02N{\cdot}m$. Using an FPGA prototype, the proposed method was evaluated experimentally in a 30 W PM brushless motor system. The proposed method maintained the minimum phase RMS current and 79 % of the motor efficiency under 0 to $0.09N{\cdot}m$ load conditions. The proposed PM brushless motor driving method is suitable for a variety of applications with a wide range of load conditions.

• Structural Engineering and Mechanics
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• v.16 no.1
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• pp.47-62
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• 2003

The nonlinear dependence aspect of various conical tool indentation parameters leading to an optimum tool semi angle value for easiest perforation is plotted and discussed explicitly in this work with the conclusion that tool angle has an optimum response towards most of the indentation parameters. Around this optimum angle, the aluminium sheets showed minimum fracture toughness as well as minimum work input to overcome the offered resistance. At the end, the mechanism leading to this phenomenon is presented with the conclusion that plastic flow dominates as the dimple semi cone angle reaches 35 and both pre and post plastic flow perforations lead the tool semi cone angle value towards this dimple cone semi angle of plastic flow initiation for its optimum performance. It is also concluded that specimen material failure is solely under tensile hoop stress and hence results into radial cracks initiation and propagation.

• Journal of Adhesion and Interface
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• v.23 no.4
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• pp.108-115
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• 2022

In this study, we synthesized poly(itaconic acid-co-acrylamide) (IAcAAM) used as a novel polymer adhesion promoter to improve the adhesion strength of surface-treated Cu lead frames and epoxy composites. IAcAAM comprising itaconic acid, acrylamide was prepared through radical aqueous polymerization. The chemical structure and properties of IAcAAM was analyzed by FT-IR, ¹H-NMR, GPC, and DSC. The surface of the copper lead frame was treated with high temperature, alkali, and UV ozone to reduce the water contact angle and increase the surface energy. The adhesive strength of Cu lead frame and epoxy composite increased with the decrease of contact angle. The adhesive strength of Cu lead frame/epoxy composite increased with the addition of IAcAAM in epoxy composite. As silica content increased, the adhesive strength of Cu lead frame and epoxy composite tended to slightly decrease.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.14 no.2
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• pp.39-44
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• 2006

The unsteady vortex lattice method is used to model lead-lag in flapping motions of a rectangular flat plate wing. The results for plunging and pitching motions were compared with the limited experimental results available and other numerical methods. They show that the method is capable of simulating many of the features of complex flapping flight. The lift, thrust and propulsive efficiency of a rectangular flat plate wing have been calculated for various lead-lag motion and reduced frequency with an amplitude of flapping angle(20o). To describe a motion profile of wing tip such as elliptic, line and circle, the phase difference of flapping and lead-lag motion was changed. And the effects of the motion profile on the aerodynamic characteristics of the flapping wing are discussed by examination of their trends.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.2
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• pp.224-227
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• 2000

Gunshot wounds to the face are often dramatic at the time of presentation. Although care must be individualized, protocol approach helps the clinician rapidly evaluate patient and plan treatment. Early X-ray films help to determine the precise trajectory. Rapid neurologic assessment and early CT scanning based on physical examination ot trajectory will allow for identification of even occult injuries early. Lead poisoning arising from bullet lead in the synovial cavity of the hip, synovial cavity of the chest and pleural space have been reported. A combination of surgical debridement and chelation therapy with oral succimer produce a satisfactory outcome. We have managed a patient with Lt facial gunshot wound and Lt mandible angle fracture by open reduction of angle fracture and surgical removal of remnant bullet and medially advanced cheek skin flap. We have obtained good result and report this case with review of literatures.