http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
국부가압 다이캐스팅 공정에서 3차원 유동 및 응고해석을 통한 자동차 변속기 Gear Housing의 주조방안 설계 최적화
박진영,김억수,박용호,박익민,Park, Jin-Young,Kim, Eok-Soo,Park, Yong-Ho,Park, Ik-Min 한국재료학회 2006 한국재료학회지 Vol.16 No.11
In the partial squeeze casting process, the filling behavior of liquid metal and solidification pattern in thick area have significant influence on the quality of casting products and die life. For the optimal casting design of automobile transmission gear housing, various analyses were performed in this study by using computer simulation code, MAGMAsoft and the simulation results were compared and analyzed with experimental results. By air pressure criteria, internal porosities caused by air entrap during the mold filling were predicted and reduced remarkably by modification of gating system. Also, optimal squeeze-time lag to apply partial squeeze pin in thick area was calculated and the castings was free from shrinkage defects with the result of solidification analysis. Consequently, casting design for automobile transmission gear housing was optimized and approved by Computer Tomography.
Al고압주조공법에서 사출슬리브 온도 조절을 통한 Chill layer의 최적 제어
박진영,김억수,박용호,박익민,Park, Jin-Young,Kim, Eok-Soo,Park, Yong-Ho,Park, Ik-Min 한국재료학회 2006 한국재료학회지 Vol.16 No.11
In this study, the effect of chill layers occurred in shot sleeve on the molten metal filling was analyzed through computer simulation. The behavior of chill layers with temperature variation of shot sleeve set from 200 to $280^{\circ}C$ was also investigated. The simulation results showed the chill layers set in the in-gates during the injection process change the main filling direction and cause turbulent flow pattern, resulting in porosities inside the castings. The amount of chill layers with the increasing temperature of shot sleeve was considerably reduced. Particularly, at the setting temperature of $280^{\circ}C$ by heat control unit, the biggest reduction in chill layers, excellent trimmed surface and the highest density were achieved, suggesting that as the optimal sleeve condition in aluminum high pressure diecasting, especially for highly complex parts like valve body.
박진영,Park Jin-Yong 대한정형외과스포츠의학회 2003 대한정형외과스포츠의학회지 Vol.2 No.2
The motions used in throwing place tremendous stresses on the soft tissues about the player's shoulder. In order to throw successfully, the shoulder complex must be capable of excessive motion, while maintaining stability of the glenohumeral joint. Injuries to the throwing player can result from acute trauma, but more commonly can be a result of overuse injuries from the repetitive throwing activity. Inbalance in the muscles and soft tissue about the shoulder can result in an injury secondary to abnormal biomechanics of the glenohumeral complex. The preventive measure a throwing player can take in order to maintain a healthy throwing shoulder is to participate in a regular shoulder strengthening program. It is when the muscles about the shoulder become imbalanced, secondary to either injury or relative weakness, that instability and injury can occur. By understanding the pitching motion and the relative contribution of the muscles, the treating physician has a framework on which to build knowledge regarding physical findings and diagnosis of shoulder injuries in throwing players. Once a diagnosis is made. a successful treatment plan may be developed for the player, including both conservative and , at time surgical means. 투구 동작은 선수 견관절의 연부 조직이 심한 스트레스를 주며 이와 같은 투구 동작을 성공적으로 시행하기 위해서는 안정된 와상완 관절 위에 좋은 운동 범위를 가지는 것이 필수적이다. 투수의 견관절 손상은 급성 외상에 의하여 발생하는 경우도 있으나 흔히 반복적인 투구에 의한 과사용 손상의 결과로 발생한다. 견관절 주위의 근육이나 연부 조직의 균형이 깨진다면 이는 와상완 관절에 생역학을 변화시켜 이차적으로 손상을 유발할 수 있다 투수가 건강한 견관절을 유지하기 위해 선행되어야 하는 것은 정기적인 견관절 강화 프로그램이지 만 근육의 손상이나 약화로 잘 맞은 균형상태가 깨진다면 견관절의 불안정성과 손상이 발생된다. 치료를 시행하는 의사는 먼저 투구 동작과 각각의 근육 연부 조직의 기능을 이해해 야 하고 이를 바탕으로 투수의 견관절 손상에 대한 이학적 검사와 진단을 시행해야 한다 진단이 시행된 후에는 보존적 치료와 수술적 치료의 장단점을 잘 이해하고 이에 대한 치료 방법을 선택해야 좋은 치료 결과를 기대할 수 있다.
박진영,안정용,허륭,최훈규,이병희,신문수,정봉섭,Park, Jin Young,Ahn, Jung Yong,Huh, Ryoong,Choi, Hun Kyu,Lee, Byung Hee,Shin, Moon Soo,Chung, Bong Sub 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.11
Objectives : Embolization of intracranial aneurysms by using Guglielmi detachable coils(GDC) is proving to be a safe method of protecting aneurysms from rupture. Occasionally, patients with unruptured intracranial aneurysms present with symptoms related to the aneurysm's mass effect on either the brain parenchyma or cranial nerves. In the present study, the authors conducted a retrospective review to evaluate the response to GDC embolization in a series of 6 patients presenting with cranial nerve dysfunction due to mass effect. Patients and Methods : Aneurysms were classified by size, shape, and amount of intraluminal thrombus. Patients were classified by duration of symptoms prior to GDC treatment(range<1 month to>4 years). Clinical assessment was performed within days of the GDC procedure and at later follow-up appointments(range 5-16 months, mean 9 months). Results : In the immediate post-GDC embolization period, one of the five patients had transient worsening of third nerve palsy, which later improved to better than baseline status. Two patients who presented with third nerve deficit from a internal carotid artery-posterior communicating artery junction aneurysm had complete recovery. One patient who presented with hemiparesis and dysarthria from a giant mid-basilar aneurysm showed improvement of these symptoms. One patient who presented with sixth cranial nerve deficit from a cavernous aneurysm showed no change at the 8-months follow-up examination. Conclusion : The endovascular treatment of intracranial aneurysms by using GDC is suggested as an alternative therapeutic method for improving or alleviating neurological deficits produced by mass effect.
수리동력학적 캐비테이션을 이용한 전자폐수 처리수에 함유된 칼슘저감에 관한 연구
박진영(Jin Young Park),김선집(Sun Jip Kim),이용우(Yong Woo Lee),이재진(Jae Jin Lee),황규원(Kyu Won Hwang),이원권(Won Kwon Lee) 大韓環境工學會 2007 대한환경공학회지 Vol.29 No.6
전자산업 중 반도체 및 LCD 공장과 같이 폐수에 불소가 다량 함유되어 있는 경우, 불소처리를 위하여 과잉으로 사용되는 소석회에 의하여 처리수의 잔류 칼슘농도가 높으며, 높은 잔류칼슘 농도는 폐수의 재이용 시 일반적으로 채택되는 membrane 공정의 불안정한 운전을 초래하게 된다. 따라서, 전자폐수의 재이용을 위하여 신뢰성 있으며, 경제적인 칼슘제거기술의 개발이 절실히 필요한 실정이다. 본 연구에서는 캐비테이션을 이용한 Hyperkinetic Vortex Crystallization(HVC) 공정을 적용하여 폐수중의 칼슘 이온의 calcification 속도를 촉진하였으며, HVC 공정 적용 시 기존 소다회법에 비하여 동일 약품 주입농도에서 31% 높은 칼슘제거효율을 보였다. 또한, 전자산업 폐수의 재이용을 위한 경제적인 칼슘제거효율인 70%를 달성하기 위한 최적 소다회 주입농도는 유입수 대비 530 mg/L였다. 반응조 내 동질의 반응 핵인 calcite seed 농도가 칼슘제거효율에 큰 영향을 주며, 최대 칼슘제거효율을 달성하기 위한 calcite seed 농도는 800∼1,200 mg SS/L이였다. 또한, 소다회 주입에 따른 calcite 발생량은 평균 0.30 g SS/g NA₂CO₃였다. HVC 케비테이션 생성장치의 설계 시 HVC 장치 통과횟수를 2∼5회 범위에서 안전율을 고려하여 용량선정을 하여야 한다. HVC 공정을 이용한 연속회분식 운전 결과, 유입수 칼슘농도 변화폭은 74∼359 mg/L(평균 173 mg/L)로 매우 컸던 반면, 처리수 칼슘농도는 30∼72 mg/L(평균 49 mg/L)로 비교적 안정적인 처리효율을 보여주었다. 본 연구결과 HVC 공정은 화학약품 사용량의 절감 및 이에 따른 화학슬러지 발생량의 감소를 기대 할 수 있는 친환경기술로 유지관리비를 최소화할 수 있는 장점이 있었다. Residual calcium concentration is high, in general, at the effluent of the fluoride removal process in the electronics industry manufacturing semiconductor and LCD. To increase the stability of the membrane process incorporated for reuse of wastewater, the residual calcium is required to be pre-removed. Hyperkinetic Vortex Crystallization(HVC) process was installed in the electronics industry manufacturing semi conductor as a pilot scale for accelerating calcification of calcium ion. Compared to the conventional soda ash method, the 31% higher calcium removal efficiency was achieved when HVC was applied at the same sodium carbonate dosage. In order to maintain the economic calcium removal target of 70% preset by manufacturer, the dosing concentration of the soda ash was 530 mg/L based on influent flowrate. The seed concentration in the reactor was one of the critical factors and should be maintained in the range of 800∼1,200 mg SS/L to maximize the calcium removal efficiency. The calcite production rate was 0.30 g SS/g NA₂CO₃ in the average. The economic HVC passing time of the mixture was in the range of 2∼5 times. Relatively, stable calcium concentration was maintained in the range of 30∼72 mg/L(average 49 mg/L) although the calcium concentration in the feed was severely fluctuated with 74∼359 mg/L(average 173 mg/L). The HVC process was characterized as environment-friendly technology reducing chemical dosage and chemical sludge production and minimizing maintenance cost.