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.

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.

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.

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.

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.

Revision of Failed Shoulder Instability Repair

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

Full-scale 저경도 납면진받침의 온도의존성에 대한 실험적 연구

박진영,장광석,이홍표,이영학,김희철,Park, Jin Young,Jang, Kwang-Seok,Lee, Hong-Pyo,Lee, Young Hak,Kim, Heecheul 한국전산구조공학회 2012 한국전산구조공학회논문집 Vol.25 No.6

납코어가 삽입된 적층고무받침은 주요 재료가 온도에 대한 의존성을 보유하고 있으므로 온도 환경이 장치의 성능에 미치는 영향이 적지 않다. 따라서, 본 논문에서는 대표적인 면진장치인 납면진받침에 대하여 실규모 장치를 제작하고 온도변화에 따른 강성 및 감쇠 특성변화에 대하여 실험을 통하여 분석하고 평가하였다. 실물 크기의 납면진받침을 사용하여 $-10^{\circ}C$, $0^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$의 온도 조건에 대하여 ISO22762:2010에서 제시하고 있는 특성시험법을 적용하여 수직강성 및 수평특성에 대하여 의존성 경향을 파악하였다. 또한, 면진받침 설계 시 주요한 평가지표로 사용되는 2차강성 및 특성강도에 대하여 해외 제조사에서 제시하고 있는 온도보정식과 시험결과를 비교하였으며 수직강성에 대한 온도의존 경향을 파악하였다. Rubber laminated bearings with lead core are highly affected by changes in temperature because key materials which are rubber and lead have temperature dependencies. In this study, two full scale LRB(D800, S=5) are manufactured and temperature dependency tests on shear properties are accomplished. The shear properties at the 3rd cycle are used at $-10^{\circ}C$, $0^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$ respectively. The double shear configuration, simultaneously testing two pieces, is applied for compression shear test in order to minimize the friction effects due to the test machine, described in ISO 22762-1:2010. Characteristic strength, post-yield stiffness, effective stiffness, equivalent damping ratio are estimated and presented coefficient due to the temperature changes.

음성구간 검출기의 실시간 적응화를 위한 음성 특징벡터의 차원 축소 방법

박진영,이광석,허강인,Park Jin-Young,Lee Kwang-Seok,Hur Kang-In 한국융합신호처리학회 2006 융합신호처리학회 논문지 (JISPS) Vol.7 No.3

본 논문에서는 다양한 잡음환경에서의 실시간 적응화 기법을 적용하기 위한 선결 과제로 다차원 음성 특정 벡터를 저차원으로 축소하는 방법을 제안한다. 제안된 방법은 특징 벡터를 확률 우도 값으로 매핑시켜 비선형적으로 축소하는 방법으로 음성 / 비음성의 분류는 우도비 검증 (Likelihood Ratio Test; LRT) 을 이용하여 분류하였다. 실험 결과 고차원 특징 벡터를 이용하여 분류한 결과와 대등하게 분류됨을 확인할 수 있었다. 그리고, 제안된 방법에 의해 검출된 음성 데이터를 이용한 음성인식 실험에서도 10차 MFCC(Mel-Frequency Cepstral Coefficient)를 사용하여 분류한 경우와 대등한 인식률을 보여주었다. In this paper, we propose the dimension reduction method of multi-dimension speech feature vector for real-time adaptation procedure in various noisy environments. This method which reduces dimensions non-linearly to map the likelihood of speech feature vector and noise feature vector. The LRT(Likelihood Ratio Test) is used for classifying speech and non-speech. The results of implementation are similar to multi-dimensional speech feature vector. The results of speech recognition implementation of detected speech data are also similar to multi-dimensional(10-order dimensional MFCC(Mel-Frequency Cepstral Coefficient)) speech feature vector.

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.