• Title/Summary/Keyword: Deformed

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A Study on the Side Collision Accident Reconstruction Using Database of Crush Test of Model Cars (모형자동차 충돌시험의 데이터베이스를 이용한 측면 충돌사고 재구성)

  • Sohn, Jeong-Hyun;Park, Seok-Cheon;Kim, Kwang-Suk
    • Transactions of the Korean Society of Automotive Engineers
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    • v.17 no.2
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    • pp.49-56
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    • 2009
  • In this study, a side collision accident reconstruction using database based on the deformed shape information from the collision test using model cars is suggested. A deformation index and angle index related to the deformed shape is developed to set the database for the collision accident reconstruction algorithm. Two small size RC cars are developed to carry out the side collision test. Several side collision tests according to the velocity and collision angles are performed for establishing the side collision database. A high speed camera with 1000fps is used to capture the motion of the car. A side collision accident reconstruction algorithm is developed and applied to find the collision conditions before the accident occurs. Two collision cases are tested to validate the database and the algorithm. The results obtained by the reconstruction algorithm show good match with original conditions with regard to the velocity and angle.

A Study on the Failure Behavior of the Reinforced Earth Wall Structures according to the Deformed Types of the Face (전면부 변형형태에 따른 보강토 벽체 구조물의 파괴거동에 관한 연구)

  • 김준석;이상덕
    • Journal of the Korean Geotechnical Society
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    • v.15 no.4
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    • pp.167-173
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    • 1999
  • In this paper the failure behavior of the reinforced earth retaining wall structures according to the deformed types of the face was studied by model test using carbon rods. In model test the behavior of the face for the model of the reinforced earth wall was divided into three cases : the displacement of the top part(case 1), the lateral displacement(case 2) and the displacement of the lower part (case 3). The photographic method was applied to examine the failure line of the deformed wall with the naked eye. The failure line shows a parabolic shape for case 1, a large circular arc for case 2 and a logarithmic spiral for case 3 in the experimental results. The design failure line for the coherent gravity structure hypothesis was most similar to the failure line for the case of the lower part displacement.

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Numerical and Experimental Flow Visualization on Nasal Airflow (비강 내 공기유동에 대한 실험 및 전산 유동가시화)

  • Kim, Sung-Kyun;Park, Joon-Hyung;Huynh, Quang Liem
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.6
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    • pp.461-467
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    • 2009
  • Knowledge of airflow characteristics in nasal cavities is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. In our laboratory, there have been a series of experimental investigations on the nasal airflow in normal, abnormal, and deformed nasal cavity models by PIV under both constant and periodic flow conditions. In this time normal and several deformed nasal cavity models, which simulate surgical operation, Turbinectomy, are investigated numerically by the FVM general purpose code and PIV analysis. The comparisons of these results are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticated cavity models. The Davis (LaVision Co.) code is used for PIV flow analysis. Average and RMS distributions have been obtained for inspirational and expirational nasal airflows in the normal and deformed nasal cavities.

Schistosomus reflexus in Korean native calf (한우 송아지의 반전성열체)

  • Kim, Chong-sup;Huh, Chan-kwen;Lee, Jong-hwan;Lee, Jong-han
    • Korean Journal of Veterinary Research
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    • v.36 no.2
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    • pp.289-296
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    • 1996
  • A case of schistosomus reflexes in Korean native female calf was observed macroscopically and radiographically. The results were summarized as follows. 1. The abdominal visceral organs were exposed. 2. The vertebral column bent laterally to the left, and the sacrum approached to the cranium by reflected caudal lumber vertebrae, presenting S-shaped lateral twisting of the vertebrae. 3. The right ribs reflected laterally and dorso-cranially from the 7th rib to 13th rib. The left ribs bent caudally from 8th rib to 13th rib. 4. The length of rudimentary 6th right rib was one half of normal size and the 7th right rib was one third. 5. The sternum was bifid split from the fourth sternebra through the xyphoid cartilage. 6. The diaphragm was intact and thoracic cavity was reduced in size. The lung and heart severely deformed in shape and size. 7. The liver markedly deformed in shape and thickness. 8. The pelvic cavity was reduced in size by compression laterally to the left. 9. The uterus horn, ovary, urinary bladder, and urethra were severely deformed in the shape and position.

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Bond of Deformed Bars to Concrete : Effects of Confinement and Strength of Concrete (철근 콘크리트 보-기둥 접합부의 부착거동에 대한 콘크리트 강도 및 보강철근의 효과)

  • 최기봉
    • Magazine of the Korea Concrete Institute
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    • v.3 no.2
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    • pp.115-121
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    • 1991
  • Slippage of beam longitudinal reinforcement at beam-column connections is an important cause of damage to reinforced concrete frames under static and dynamic loads, This paper summarizes the results of an experimen¬tal study on the effects of confinements and compressive strength of concrete on the local bond stress-slip cha¬racteristics of deformed bars. I t is concluded from experimental results that, as far as the bond splittmg cracks are restrained by the vertical column reinforcement, confinement of concrete by transverse reinforcement has insignigicant direct effect on the local bond behavior. The ultimate bond strength, however, Increases pro¬portionally with the square root of concrete compressive strength. An empirical model was developed for local bond st ressslip relationslip of deformed bars in confined concrete of different compressive strengths.

Finite Element Analysis of Punch Forming of Superplastic Materials (초소형재료의 펀치성형에 관한 유한요소해석)

  • Huh, Hoon;Lee, Ki-Seok;Choi, Yeong-Jun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.2
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    • pp.440-449
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    • 1996
  • Superplastic punch forming of sheets is simulated by a finite element method to obtain the optimal punch speed and the related deformed shapes. The punch forming has an advantage of guaranteeing the desired accuracy inside a product and controlling the thichness of a deformed sheet more accurately than blow forming. The finit element code developed is associated with the contact algorithm and the control algorithm of punch speed for the optimum forming. The simulation demonstrates that the variation of the thichness in a blank sheet affects the punch speed and the final distribution of the thichness in a product. The analysis proposes that a ring-typed thichness controller is very effective in controlling the thichness of a deformed sheet appropriately.

A Study on the Cooling Effects of Mist in the Grinding (연삭 가공시 Mist의 냉각효과에 관한 연구)

  • 이석우;최헌종;김대중
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.918-921
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    • 2001
  • In grinding process, the heat of $1200^{\circ}$~$1500^{\circ}$ on the grinding area between grinding wheel and workpiece is generated. It decreases the surface integrity of workpiece and causes the thermal damages such as the deformed layer, residual stress and grinding burn. Generally coolant is widely used for preventing the heat generation on the grinding area, but it deteriorates the working condition by polluting the atmosphere of workplace and in the end pollutes the environment. The grinding methods using the compressed cold air and mist are the cooling methods to substitute conventional coolant. They can decrease the environmental pollution through not using coolant any more or minimizing it. In this study, the cooling effects of grinding methods using the compressed cold air and mist have been investigated. The grinding system equipped with the water bathe and mist spray nozzle was developed. The energy partition to workpiece through measuring the temperature on the workpiece surface was calculated. The surface integrity of workpiece and thermal damage like the deformed layer were analyzed.

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A Study on Interlayer Dielectric CMP Using Diamond Conditioner (다이아몬드 컨디셔너를 이용한 ILD CMP에 관한 연구)

  • 서헌덕;김형재;김호윤;정해도
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.86-89
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    • 2003
  • Chemical Mechanical Planarization(CMP) has been accepted as the most effective processes for ultra large scale integrated (ULSI) chip manufacturing. However, as the polishing process continues, pad pores get to be glazed by polishing residues, which hinder the supply of new slurry. And pad surface is ununiformly deformed as real contact distance. These defects make material removal rate(MRR) decrease with a number of polishied wafer. Also the desired within-chip planarity, within wafer non-uniformity(WIWNU) and wafer to wafer non-uniformity(WTWNU) arc unable to be achieved. So, pad conditioning in CMP Process is essential to overcome these defects. The eletroplated or brazed diamond conditioner is used as the conventional conditioning. And. allumina long fiber, the jet power of high pressure deionized water, vacuum compression. ultrasonic conditioner aided by cavitation effect and ceramic plate conditioner are once used or under investigation. But. these methods arc not sufficient for ununiformly deformed pad surface and the limits of conditioning effect. So this paper focuses on the characteristics of diamond conditioner which reopens glazed pores and removes ununiformly deformed pad away.

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Micro Forming of Bulk Metallic Glass using the Deformation Behavior in the Supercooled Liquid Region (과냉각 액체 영역에서의 변형거동을 이용한 벌크 비정질 합금의 미세성형 기술 개발)

  • 옥명렬;서진유;홍경태
    • Transactions of Materials Processing
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    • v.13 no.1
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    • pp.9-14
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    • 2004
  • Recently, various bulk metallic glasses (BMG's) having good mechanical and chemical properties were developed. BMG's can easily be deformed in the supercooled liquid region, via viscous flow mechanism. By using the viscous flow, the very low pressure is needed to deform the materials. In this study, we investigated the structural transition and deformation behavior of Vitreloy 1 (Zr/sub 41.2/Ti/sub 13.8/Cu/sub 12.5/Ni/sub 10/Be/sub 22.5/) using TMA and DSC. We applied the results to the micro forming process. The forming condition was chosen based on the viscosity data from TMA, and Si wafer with micro patterns on the surface was used as a forming die. The deformed surface was analyzed by SEM and 3D Surface Profiling System. The alloy showed good replication of the patterns. Quantitative measurement of roughness was useful to evaluate the replication. Surface condition of the deformed surface was determined by the initial surface condition.

A CASE REPORT OF SEVERE FACIAL ASYMMETRY WITH TMD (악관절 장애를 동반한 심한 안모 비대칭 환자의 치험례)

  • Kim, Yeo-Gab;Lee, Sang-Chull;Ryu, Dong-Mok;Oh, Sung-Hwan
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.14 no.4
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    • pp.255-268
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    • 1992
  • There are various modalities in the treatment of facial asymmetry, but in severe case with TMD by actively growing deformed condyle, the treatment choice is removing the condyle growth center and TMD symptom such as click or muscular discomfort. In our one case, the patient was complain of facial asymmetry. There are severe deformed condyle head with bird-head fashion and enlarged mandibular ramus and body vertically about 18 mm, overgrowthed Rt. mandible body horizontally about 20 mm. She had intermittent Lt. TMJ clicking and muscular discomfort. The author diagnosed it as Lt. hemimandibular hyper-plasia & R, hemimandibular elongation, a combination form with TMD. the condyle was in active growing state in scintigraphic analysis. So we extirpated the deformed condyle by intrasoral sagittal split ramus osteotomy and reshaped the condyle and mandibular distal fragment extraorally. The distal fragment was readapted in glenoid fossa and fixated. In Rt. mandibular body area, autogenous onlay bone graft on the inferior border of mandible was performed to correct the asymmetry. The clicking and facial asymmetry was corrected and we report this results with other literature findings.

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