http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
김병주(Byungjoo Kim),노근제(Keunje Noh),김혁수(Hyuksoo Kim),박기홍(Kihong Park) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11
This paper proposes an Intelligent Torque Distribution(ITD) algorithm for enhancing the driving performance and cornering stability of a vehicle. In the vehicle’s longitudinal maneuver, the ITD logic improves the acceleration performance by the front/rear torque distribution. In the cornering maneuver, the ITD logic tries to maintain the vehicle’s lateral stability by using the combined torque distribution strategies at for wheels. For the control logics, the PID and the sliding mode control methods were adopted for the longitudinal and lateral controls, respectively. The performance of the ITD system was validated using and independent four wheel drive vehicle model developed with CarSim and Simulink. The simulation results are to be presented and discussed in this paper.
백중철,김병주,Paik, Joongcheol,Kim, Byungjoo 한국수자원학회 2023 한국수자원학회논문집 Vol.56 No.-
보와 저낙차 댐과 같은 하천횡단구조물을 통과하는 흐름은 도수 현상을 동반하는 급변류가 지배적이다. 구조물 하류에서 도수로 인한 유속과 수면의 강한 비정상성은 수공구조물의 안정에 영향을 줄 수 있다. 특히, 높은 Froude 수 조건에서 발생하는 정상도수는 공기연행이 현저하게 발생하여 흐름 특성은 더욱 복잡해진다. 이 연구에서는 Froude 7.3 조건에서 발생하는 정상도수를 모의하기 위해서 큰와모의 기법과 하이브리드 VoF 기법을 이용한 수치모의를 수행하였다. 수치모의 결과는 구조물 하류 바닥면에서 계측된 순간최대압력과 시간평균압력 분포를 유사하게 재현하는 것으로 나타났다. 단, 구조물 직하류에서의 순간최소압력 분포는 대상으로 하는 실험 계측값과 반대의 양상을 보이지만, 유사한 다른 시험과는 같은 양상을 보임으로써 본 연구에서 수행한 수치모의는 합리적으로 압력변동을 예측하는 것으로 판단된다. 도수 중앙부에서의 연직방향 유속분포와 공기농도분포는 유사한 조건의 실험 결과들과 자기상사성을 보이면서 양호하게 일치하는 것으로 나타났다. 이러한 결과는 본 연구에서 적용한 큰와모의 기법과 하이브리드 VoF 기법이 높은 Froude 수 조건에서 강한 공기연행을 동반하는 도수현상을 양호하게 재현할 수 있음을 보여준다. The flow passing through river-crossing structures such as weirs and low-fall dams is dominated by rapidly varied flow including hydraulic jump. The intense unsteadiness of flow velocity and free surface profile affects the stability of such hydraulic structures. In particular, the steady hydraulic jump generated at high Froude number conditions includes remarkably air entrainment, making the flow characteristics more complicated. In this study, a large-eddy simulation was performed for turbulence effect and the hybrid VoF technique to simulate the steady hydraulic jump at the Froude number of 7.3 and the Reynolds number of 15,700. The results of the numerical simulation showed that the instantaneous maximum pressure and time-average pressure distribution calculated on the bottom surface downstream of the structure could be reasonably well reproduced being in good agreement with the experimental values. However, the instantaneous minimum pressure distribution in the direct downstream of the structure shows the opposite pattern to the target experimental measurement value. However, the numerical simulation performed in this study is considered to reasonably predict the minimum pressure distributions observed in various experiments conducted at similar conditions. The vertical distributions of flow velocity and air concentration computed in the center of the hydraulic jump were found to be in good agreement with the experimental results measured under similar conditions, showing self-similarity. These results show that the large eddy simulation and hybrid VoF techniques applied in this study can reproduce the hydraulic jump with strong air entrainment and the resulting intense free surface and pressure fluctuations at high Froude number conditions.
김혁수(Hyuksoo Kim),김병주(Byungjoo Kim),박기홍(Kihong Park) 한국자동차공학회 2009 한국자동차공학회 학술대회 및 전시회 Vol.2009 No.11
The ESP system is a chassis control module that improves the vehicle’s lateral stability by generating a compensating yaw moment with asymmetric brake force distribution among four wheels. The reference vehicle model can affect the overall control performance since the ESP system judges the vehicle stability based upon the model. Currently a 2 DOF bicycle model is most widely used for this purpose due to its simplicity and moderate capability of describing lateral vehicle motions. In this paper, feasibility study of using a 3 DOF vehicle model with roll motion as an ESP reference vehicle model has been conducted. Through simulation, the performance of ESP was compared and discussed when using the reference vehicle models with and without roll motions.
Mass balance법에 의한 농약 표준물질의 순도 분석
김승환 ( Seung-hwan Kim ),김병주 ( Byungjoo Kim ),주광국 ( Kwangguk Joo ),지수언 ( Su-eon Ji ),정대원 ( Dae-won Chung ),이석기 ( Seok-ki Lee ) 한국환경분석학회 2021 환경분석과 독성보건 Vol.24 No.3
Imazamox, a widely used herbicide, is currently managed by the Pesticide MRLs and Positive List System of the Ministry of Food and Drug Safety, and the development of reliable standard materials for analysis is urgently required. To confirm the reliability of the mass balance method, we measured the purity of the imazamox reference material (RM) certified by an RM producer accredited with ISO Guide 34 and estimated measurement uncertainty. According to this method, the content of structurally similar organic impurities was measured using high-performance liquid chromatographic coupled with ultraviolet (HPLC-UV), and the moisture, volatile impurities, and non-volatile impurities were quantitatively analyzed using a thermogravimetric analyzer (TGA). Purity and measurement uncertainty were calculated based on analysis of the HPLC-UV and TGA results obtained, and the validity of these values was confirmed by comparing with the values provided in the RM certificate.