http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
원심 압축기 베인 디퓨져내 비정상 유동의 수치해석적 연구
황성목(Sung-Mok Hwang),한화택(Wha-Taek Han),김원갑(Won-Kap Kim) 한국유체기계학회 2001 유체기계 연구개발 발표회 논문집 Vol.- No.-
Interaction of flow through an Impeller and a Vaned Diffuser in Centrifugal Compressor was investigated using the 3-dimensional Navier-Stokes solution method. To consider the interaction effect of impeller and vaned diffuser, Inlet boundary conditions are imposed with the results of the steady calculation of the impeller and rotates with time. The results have been compared to steady computation results and experiment. From this, it is discussed about the compatability of the method and the advantage and disadvantage of the steady calculation.
Median HRIR Customization via Principal Components Analysis
황성목(Hwang, Sung-Mok),박영진(Park, Young-Jin) 한국소음진동공학회 2007 한국소음진동공학회 논문집 Vol.17 No.7
A principal components analysis of the entire median HRIRs in the CIPIC HRTF database reveals that the individual HRIRs can be adequately reconstructed by a linear combination of several orthonormal basis functions. The basis functions represent the inter-individual and inter-elevation variations in median HRIRs. There exist elevation-dependent tendencies in the weights of basis functions, and the basis functions can be ordered according to the magnitude of standard deviation of the weights at each elevation. We propose a HRIR customization method via tuning of the weights of 3 dominant basis functions corresponding to the 3 largest standard deviations at each elevation. Subjective listening test results show that both front-back reversal and vertical perception can be improved with the customized HRIRs.
Comparison of Head-related Transfer Function Models Based on Principal Components Analysis
황성목(Hwang, Sung-Mok),박영진(Park, Young-Jin),박윤식(Park, Youn-Sik) 한국소음진동공학회 2008 한국소음진동공학회 논문집 Vol.18 No.6
This study deals with modeling of head-related transfer functions(HRTFs) using principal components analysis(PCA) in the time and frequency domains. Four PCA models based on head-related impulse responses(HRIRs), complex-valued HRTFs, augmented HRTFs, and log-magnitudes of HRTFs are investigated. The objective of this study is to compare modeling performances of the PCA models in the least-squares sense and to show the theoretical relationship between the PCA models. In terms of the number of principal components needed for modeling, the PCA model based on HRIR or augmented HRTFs showed more efficient modeling performance than the PCA model based on complex-valued HRTFs. The PCA model based on HRIRs in the time domain and that based on augmented HRTFs in the frequency domain are shown to be theoretically equivalent. Modeling performance of the PCA model based on log-magnitudes of HRTFs cannot be compared with that of other PCA models because the PCA model deals with log-scaled magnitude components only, whereas the other PCA models consider both magnitude and phase components in linear scale.