http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
高次스펙트럼을 利用한 機關 排氣系의 非線型 脈動壓力 解釋에 관한 硏究
이준서(J.S.Lee),이민호(M.H.Lee),김명균(M.G.Kim),김봉각(B.K.Kim),임인권(I.G.Lim),차경옥(K.O.Cha) 한국자동차공학회 1998 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1998 No.5_1
The engine exhaust noise is mainly made of the pulsating gas flow and pulsating pressure at a very high pressure level. Frequently, this pulsating pressure level is out of the pressure level range which the linear acoustic theory is applicable. The conventional prediction method which is based on the linear acoustic theory gives an overestimate in comparison with results measured in operating engines. This paper, as the first step for solving this problem, proposes a non linear effect of pulsating pressure waves. The phenomenon proposed here is identified by using of higher order spectrum(bicoherence),<br/>
이민호(M.H.Lee),이준서(J.S.Lee),김봉각(B.K.Kim),임인권(I.G.Lim),차경옥(K.O.Cha) 한국자동차공학회 1997 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1997 No.11_1
A pulsating flow is studied experimentally through a pipe and the results are compared with the numerical ones obtained by a one-dimensional numerical scheme. The numerical scheme is utilized the method of characteristics to solve the general equations of one-dimensional unsteady gas flow. This analysis is then combined with boundary models. based on quasi-steady flow approach. to give a complete treatment of the flow behavior in the exhaust system. The noise characteristics of exhaust systems is analyze through radiated noise analysis. The predictions are compared with measured results and show a high degree of correlation in amplitude and phasing.<br/>
線形系와 2乘特性系의 結合 모델에 대한 스펙트럼 解析에 관한 硏究
李焌瑞,張宇種,金鳳珏,車京玉 明知大學校 産業技術硏究所 1998 産業技術硏究所論文集 Vol.17 No.-
This Paper describes a number of theoretical formulas to analyze the frequency domain properties of Gaussian input data passing through non-linear square-law systems. From measurement of input data and output data only, results are obtained to identify the separate frequency response functions for two models of linear systems in parallel with non-linear square-law systems. This formulas indicates also how to analyze other types of non-linear models by employing similar techniques.