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.

퉁퉁마디를 가해하는 퉁퉁마디뿔나방 Scrobipalpa salinella (Zeller) (나비목, 뿔나방과)의 재발견 및 피해

박진영,박규택,Park, Jin-Young,Park, Kyu-Tek 한국응용곤충학회 2008 한국응용곤충학회지 Vol.47 No.4

전남 신안군의 퉁퉁마디 재배지에서 대 발생하여 피해를 초래한 해충이 뿔나방과의 Scrobipalpa salinella (Zeller)로 확인되었다. 본 종은 Park & Ponomarenko (2006)에 의해 국내에서 처음 보고된 바 있다. 그러나 동정이 어려운 암컷 한 개체를 대상으로 하였으며, 염생식물이 없는 산간지역에서 발견된 점 등으로 분포에 대한 의문점이 상존해 왔었으나 금번 조사결과로 국내 분포가 재 확인되었다. 종의 분류동정을 위한 성충과 생식기의 사진 제공과 함께 유충의 발생 및 피해에 대해 조사된 내용을 기술하였다. In a cultivated field of Salicornia europae in the Jeonam Province, Korea, Scrobipalpa salinella (Lepidoptera, Gelechiidae) which feeds and leads to a serious damage was found. The discovery of this species is to reconfirm its distribution in Korea because the first report by Park and Ponomarenko (2006) was based on a single female and it was collected in a montane area far from seaside where its host plants, halophytes, are planted. For identification, photos of imago and genitalia are given, and the damage by larvae on Salicornia europae are noted.

진동 자극 유무에 따른 호흡 저항 훈련 시 폐 기능과 호흡근의 즉각적인 차이가 있을까?

박진영,김예슬,박현주,이명모,Park, Jin-Young,Kim, Ye-Seul,Park, Hyun-Ju,Lee, Myung-Mo 대한물리치료과학회 2018 대한물리치료과학회지 Vol.25 No.3

Purpose: The purpose of this study was to investigate the effect of whole body vibration combined breathing resistance on lung capacity and respiratory muscle and to suggest a mediation method for improvement of respiratory function and lung function in the future. Methods: This study was a preliminary study design of two groups of 54 healthy young adults who were randomly assigned to an experimental group (n=27) with core exercise combined with respiratory resistance and whole body vibration and a control group with respiratory resistance and core exercise (n=27). All interventions consisted of 6 core exercises every 40 seconds and rest for 20 seconds. To compare the effects of intervention, we measured spirometry and respiratory muscle strength. Results: Both the experimental group and the control group showed a significant increase in Forced vital capacity (FVC) and Maximum voluntary ventilation (MVV) (p<.05). However, FEV1 and FEV1% were significantly increase only in the experimental group (p<.05). FVC, FEV1%, Maximum Inspiratory Pressure (MIP), Maximum Expiratory Pressure (MEP) showed more significant increase in the experimental group than the control group. Conclusion: These findings indicate that whole-body vibration combined breathing resistance is an effective intervention for people, with FVC, FEV1%, MIP, MEP increase.

아동기에 주의력결핍 과잉행동증상을 경험한 성인의 정신병리와 기질 성격 요인

송열매(Yul-Mai Song),이건석(Kounseok Lee),한덕현(Doug Hyun Han),이영식(Young Sik Lee),민경준(Kyung Joon Min),박진영(Jin Young Park),김준원(Jun Won Kim) 대한소아청소년정신의학회 2013 소아청소년정신의학 Vol.24 No.4

Objectives:The objective of this study is to find out the differences in psychopathology, temperament, and character factors between young adults with and without childhood attention-deficit hyperactivity disorder (ADHD) symptoms. Methods:The subjects consisted of 314 university students (male=72, female=242) in Gongju. They were divided into childhood ADHD group (N=54) and normal group (N=260) to the Wender-Utah Rating Scale. Participants were assessed using Korean Adult ADHD Scale, Beck Depression Inventory-II, Beck Anxiety Inventory, Kimberly Young’s Internet Addiction Test, Barratt Impulsiveness Scale, Paranoia Scale, Korean-Schizotypal Ambivalence Scale, Lubben Social Network Scale, and Temperament and Character Inventory-Revised. Descriptive statistics, t-test, chi-square, spearman correlation, and stepwise multiple regression were applied to analyze the data. Results:Participants with childhood ADHD symptoms had high level of adult ADHD symptoms (p<.001), impulsiveness(p=.001), depression (p<.001), anxiety (p<.001), internet addiction (p<.001), paranoia tendency (p<.001) and low level of selfesteem (p<.001) compared to normal group. Self-directedness (p<.001) was lower, Harm avoidance (p=.001) and Self-transcendence (p=.029) were higher in the childhood ADHD group. In correlation and stepwise multiple regression, childhood ADHD symptoms were significantly associated with cooperativeness (r=-0.515 and β=-0.547, p<.001 respectively). Conclusion:This result showed that young adults with childhood ADHD symptoms had various forms of psychopathology and childhood ADHD symptoms were influenced by character such as cooperativeness. Therefore, more thorough evaluation regarding childhood ADHD symptoms is needed.

초기 설계단계의 가용정보를 활용한 도로 배수공종의 LCA기반 환경부하량 산정모델

박진영,김병수,Park, Jin-Young,Kim, Byung-Soo 한국건설관리학회 2018 건설관리 : 한국건설관리학회 학회지 Vol.19 No.3

기후변화에 대한 우려가 커지면서 건설산업에서도 환경부하를 줄이기 위해 지속적으로 노력하고 있으며, 환경부하를 산정하기 위한 효과적인 방법론으로써 LCA (life cycle assessment)가 제시되고 있다. 그러나, LCA는 환경부하량 산정을 위해 작업에 투입되는 자원량에 대한 정보가 필요하기 때문에 이러한 정보의 확보가 어려운 초기 설계단계의 환경적 검토에는 활용되지 못하고 있다. 이 연구에서는 도로의 배수시설물을 대상으로 표준단면에 기반한 작업물량산출체계를 개발하고 환경부하량을 산출할 수 있는 모델에 활용하였다. 이 모델은 초기 설계단계의 가용정보만으로 LCA에 필요한 자원량을 산정함으로써 환경부하량을 산출할 수 있다. 모델의 유효성을 검증하기 위해 5개의 검증사례를 적용하였으며 원단위추정모델 및 회귀모델과 비교하였다. 그 결과 평균 9.94%의 절대오차율평균을 나타내 다른 모델보다 상대적으로 정확하며 초기 설계단계에서 사용할 수 있는 유효한 모델이라는 점이 확인되었다. Due to the increasing concern about climate change, efforts to reduce environmental load are continuously being made in construction industry, and life cycle assessment (LCA) is being presented as an effective method to assess environmental load. Since LCA requires information on construction quantity used for environmental load estimation, however, it is not being utilized in the environmental review at the initial design stage where it is difficult to obtain such information. In this study, a construction quantity computation system based on the standard section was developed for the drainage facilities of the road and utilized in the model to calculate the environmental load. This model can estimate the environmental load by calculating the amount of resources required for LCA using only the information available at the initial design stage. To verify the validity of the model, five validation cases were applied and compared with the unit estimation model and the multiple regression analysis model. As a result, it is confirmed that the mean absolute error rate is 9.94%, which is relatively accurate and effective model in the initial design stage.

고속 고밀도 WDM 광전송 시스템에서의 ASK-SSB와 PSK-SSB 변조 방식의 성능 분석

박진영,최윤희,박상규,Park Jin-Young,Choi Yoon-Hee,Park Sang-Gyu 대한전자공학회 2004 電子工學會論文誌-TC (Telecommunications) Vol.41 No.12

This research investigates the performance of the optical transmissions systems using the SSB modulation format The focus was on the spectral efficiency of the WDM systems and the transmission penalties due to the fiber nonlinearities. By investigating the performance obtained with ideal SSB signal, we set the upper limit of the performance which can be obtained by SSB technology. Furthermore, we investigated the performance obtainable with SSB signals which can be generated with realizable devices. Since SSB formats are more susceptible to the fiber nonlinearities, SSB formats exhibited inferior transmission performances compared to the DSB format. However, within the 500~1000 km transmission range, which is the focus of this research, it was found that the WDM systems with 12.5 GHz channel spacings might benefit from the SSB modulation techniques. 본 논문에서는 SSB 변조를 이용한 광전송 시스템의 주파수 효율성 및 비선형성에 대한 저항성 등을 규명하였다. 이상적인 SSB 신호를 사용하여 도달할 수 있는 성능의 한계를 확인하는 한편, 실제 제작이 가능한 SSB 변조기가 생성할 수 있는 신호에서 얻을 수 있는 성능을 컴퓨터 시뮬레이션을 통하여 살펴보았다. 이를 통해 SSB 변조된 신호는 일반적으로 DSB 변조된 신호에 비해서 광섬유의 비선형성에 취약하나 본 연구에서 목표로 삼고 있는 전송거리가 500~1000 km 미만인 12.5 GHz 채널 간격의 WDM 시스템에서는 SSB 신호가 DSB 신호에 비해 우수한 성능을 보일 수 있음을 확인하였다.

Revision of Failed Shoulder Instability Repair

박진영,최진형,Park, Jin-Young,Choe, J.H. 대한관절경학회 2006 대한관절경학회지 Vol.10 No.1

Laser-Induced Breakdown Spectroscopy (LIBS)를 이용한 방사성 스트론튬 오염물질에 대한 신속한 모니터링 기술

박진영,김현아,박기홍,김경웅,Park, Jin-young,Kim, Hyun-a,Park, Kihong,Kim, Kyoung-woong 대한자원환경지질학회 2017 자원환경지질 Vol.50 No.5

Cs-137 (반감기 : 30.17년)과 더불어 중요한 원자력발전소 주변 환경감시대상 방사성 핵종 가운데 하나인 순수한 베타방출체인 Sr-90 (반감기 : 28.8년)에 대한 신속하고 용이한 모니터링 방법을 연구하였다. 스트론튬은 칼슘과 같은 2족 알칼리 토금속에 속해 있어서 전자배치나 크기가 비슷하며 최외각전자를 2개 가지고 있기 때문에 화학적으로 칼슘과 치환될 수 있다. 이러한 유사한 화학적 성질로 인해서 환경으로 유출시 물, 토양 및 농작물을 통한 먹이사슬을 거쳐서 인체로 쉽게 유입될 수 있으며, 인체 유입 시 뼈에 쉽게 침적되어 장기간 (생물학적 반감기 : 약 50년) 동안 독성을 유발한다. 스트론튬은 매우 환원성이 있고 특이 반응으로 습식분석이 어려우며, 특히 원자력발전소에서 감시하고 있는 방사성 스트론튬은 복잡한 분석절차, 고가의 분석 장비 사용 및 화학 전처리약품 다량 사용 등으로 분석의 정확도 저하는 물론 고비용에 따른 문제를 안고 있다. 따라서 펄스에너지를 사용하여 시료에 플라즈마를 생성시켜 고유 스펙트럼을 이용해 시료내 원소를 분석하는 Laser-Induced Breakdown Spectroscopy (LIBS) 분석기법을 도입하여 전처리 과정 없이 수 초 내에 분석이 가능하고 현장에서 실시간으로 측정 가능한 스트론튬 원소의 정량분석 방법을 도출하였다. 다양한 분석에 필요한 시료기판을 개발하여 레이저, 파장 및 시간분해능의 최적화로 분석 감도를 향상시키고 방해이온에 대한 영향 평가로 액체시료의 정량분석을 가능하게 하여 신속한 모니터링 체계를 구축하게 하였다. 이는 원자력발전소로부터 방출되고 있는 방사성 폐수의 실시간 모니터링에 효과적으로 적용될 수 있으며, 더 나아가 후쿠시마 원전사고와 같은 비상시 모니터링 수단으로 적용 될 수 있다. Along with Cs-137 (half-life: 30.17 years), Sr-90 (half-life: 28.8 years) is one of the most important environmental monitoring radioactive elements. Rapid and easy monitoring method for Sr-90 using Laser-Induced Breakdown Spectroscopy (LIBS) has been studied. Strontium belongs to a bivalent alkaline earth metal such as calcium and has similar electron arrangement and size. Due to these similar chemical properties, it can easily enter into the human body through the food chain via water, soil, and crops when leaked into the environment. In addition, it is immersed into the bone at the case of human influx and causes the toxicity for a long time (biological half-life: about 50 years). It is a very reductive and related with the specific reaction that makes wet analysis difficult. In particular, radioactive strontium should be monitored by nuclear power plants but it is very difficult to be analysed from high-cost problems as well as low accuracy of analysis due to complicated analysis procedures, expensive analysis equipment, and a pretreatment process of using massive chemicals. Therefore, we introduce the Laser-Induced Breakdown Spectroscopy (LIBS) analysis method that analyzes the elements in the sample using the inherent spectrum by generating plasma on the sample using pulse energy, and it can be analyzed in a few seconds without preprocessing. A variety of analytical plates for samples were developed to improve the analytical sensitivity by optimizing the laser, wavelength, and time resolution. This can be effectively applied to real-time monitoring of radioactive wastewater discharged from a nuclear power plant, and furthermore, it can be applied as an emergency monitoring means such as possible future accidents at a nuclear power plants.

국내 건설공사 시공 VE 제도 인식조사에 기반한 개선방안

박진영,서호형,김병수,Park, Jin-Young,Seo, Ho-Hyong,Kim, Byung-Soo 한국건설관리학회 2018 건설관리 : 한국건설관리학회 학회지 Vol.19 No.3

건설사업 VE는 크게 설계단계 VE와 시공단계 VE로 분류되며, 적용 시기가 빠를수록 그 효과가 향상된다. 이에 따라 설계단계 VE가 2000년에 법제화되어 활발하게 적용되고 있다. 하지만 설계 VE 제도와 상호보완적일 수 있는 시공 VE의 활성화가 절실하다. 그동안 시공 VE 제도의 필요성, 기술개발보상제도의 개선, 시공 VE의 구체적인 실천방안 등을 제시하여 시공 VE의 활성화를 위해 많이 노력하였지만, 관련 법 규정의 미비로 인하여 효과적이지 못하였다. 본 연구는 이러한 국내 현실을 인식하고 시공 VE의 활성화를 위해 국내외 시공 VE 제도를 비교 및 분석하고, 건설산업 각 분야 전문가 설문조사를 실시하여 국내 건설산업에 적합한 시공 VE 제도의 개선방안을 제안하였다. Construction business VE is classified into design stage VE and construction stage VE. The faster the application, the better the effect. Therefore, the design stage VE was legislated in 2000 and actively applied. However, it is urgent to activate the construction VE, which is complementary to the design VE system. In the meantime, we have made a lot of efforts to activate construction VE by suggesting the necessity of construction VE system, improvement of technology development compensation system, concrete implementation method of construction VE, but it was not effective due to lack of related laws. This study compares and analyzes construction VE system in Korea and abroad for the activation of construction VE after recognizing such domestic reality. A survey of experts in each field of the construction industry was conducted and suggestions for improvement of construction VE system suitable for domestic construction industry were suggested.