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SAMPLING PRINCIPLE AND TECHNOLOGY IN WAVELET ANALYSIS FOR SIGNALS

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Chinese Journal of Mechanical Engineering 1998年第4期11卷 10-16页

作者： Qin, Shuren Chen, Zhikui Xu, Mingtao Tang, Baoping Chongqing univ China

Sampling principle and characteristics and edge effect of orthogonal wavelet transform of signals are researched. Two samples of signals and wavelet bases must be taken in wavelet transform. In the second sample sampling interval or sampling length in different frequency range will be automatically adjusted. Wavelet transform can detect singular points. Both ends of signals are singular points. Edge effect is not avoidable.

关键词： Signal Sample Wavelet transform Localization Edge effect

STUDY ON THE CUTTING TEMPERATURE IN GEAR HOBBING

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Chinese Journal of Mechanical Engineering 1999年第2期12卷 63-68页

作者： Liu, Dawei Bai, Zhimin Guo, Hongqi Qingdao univ China

According to work tool thermocouple principle,the equipment for measuring hobbing temperature is *** changing character of cutting temperature in gear hobbing,the relation between cutting conditions and hobbing temperature,and the influence of cutting conditions on hobbing temperature are discussed by means of *** these have provided the reference standards for the equitably selecting cutting conditions and geometrical parameter of hob,prolonging the life of gear hobs,and predicting processes of gear hobbing.

关键词： Gear hobbing Cutting temperature Cutting conditions

EXPERIMENT STUDY ON CONSOLIDATING EFFECT OF LOOSE STRUCTURE IN HEAVY INGOT

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Chinese Journal of Mechanical Engineering 1998年第1期11卷 24-29页

作者： Li, Weimin Qin, Siji Xu, Jisheng Yanshan univ China

Experiments on consolidating process and mechanism of internal loose structures in heavy ingots are studied by taking stretching technology as example Considering various detecting indexes,the equivalent relationships of forging ratios which are required by different forging processes with parameters are *** experimental methods and basis can be provided for the studying the of forging heavy ingots

关键词： Consolidation of loose structure Ingot Simulation experiment

ESTIMATION OF REACTIVITY RATIOS OF METHYL ACRYLATE WITH N-ARYLMETHACRYL-AMIDE COPOLYMERS BY ~1H NMR METHOD

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Chinese Journal of Polymer Science 1990年第1期8卷 10-16页

作者： DING Youjun and QI Daquan (De partment of Chemistry, Pekinng university, Beijing) Peking univ China

The copolymerizations of methyl acrylate （MA） with different N- arylmethacrylamide （N-ArMA） were carried out in benzene solution by free radical initiation. The compositions of the copolymers were deter mined by;H NMR method. The monomer reactivity ratios were calculated by the Fineman-Ross （F-R） method. The reactivity ratios and the activity of various N-ArMA with MA were investigated.

关键词： Reactivity Ratios Copolymerization Methyl Acrylate N-Arylmethacrylamide ~1H-NMR Method.

Fuzzy　Consistent　Matrix　and　Its　Application

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Journal of Systems Engineering and Electronics 1997年第1期8卷 57-64页

作者： Yao, Min Zhang, Sen Hangzhou univ China

This paper presents a kind of fuzzy consistent matrix and introduces its application in analytic hierarchy process and adaptive fuzzy reasoning.

关键词： Fuzzy consistent matrix Analytic hierarchy process Fuzzy reasoning.

ANALYSIS OF COEXISTENCE OF TWO KINDS OF MACRO-DEFECTS IN CUP-CUP AXISYMMETRIC COMBINED EXTRUSION

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Chinese Journal of Aeronautics 1990年第1期5卷 58-66页

作者： Li Miaoquan and Wu Shichun Northwestern Polytechnical university Northwestern Polytechnical univ

In this paper, the relationships between the region of the two coexisting kinds of macro-defects and the reduction in area, as well as between the region and the relative residual thickness of the billet are studied for the cup-cup axisymmetric combined extrusion, on the basis of the analytical expression obtained by the upper-bound approach. The presented model and conclusions are confirmed by the experimental results in this paper.

关键词： CUP ANALYSIS OF COEXISTENCE OF TWO KINDS OF MACRO-DEFECTS IN CUP-CUP AXISYMMETRIC COMBINED EXTRUSION

Study on Electrochemical Formation of Neodymium-Iron Alloy

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Rare Metals 1989年第3期9卷 9-14页

作者： Yang, Qiqin Liu, Guankun Fang, Zhongan Sha, Lichang Zhongshan univ China

The cyclic voltammetry was used to investigate the electrode processes of Nd(III) reduced on iron electrode and Nd(III),Fe(II) reduced on molybdenum electrode in molten chlorides. The Nd-Fe and Nd-rich RE-Fe alloys contained rare earth up to 90wt% were prepared by consumable cathode and electrolytic codeposition. The mechanism of electrochemical formation of Nd-Fe alloy had been discussed.

关键词： Electrolytic Analysis Magnets Manufacture Neodymium Compounds Electrolytic Reduction Neodymium Iron Boron Alloys Magnetic Properties Salts Molten

VIBRATION CONTROL AND EXPERIMENT OF THREE-RING REDUCER

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Chinese Journal of Mechanical Engineering 1998年第4期11卷 72-78页

作者： Zhu, Caichao Qin, Datong Li, Runfang Chongqing univ China

The three ring reducer is studied both in theory and experiment. In order to improve the dynamic characteristics and reduce the vibration and noise, based on the sensitivity analysis of design parameters of dynamic characteristics, the system geometry parameters are optimized, and the structure of reducer is developed according to the optimum result, then the specimens of reducer are designed and manufactured. The effect of the structure development has been verified by comparing the original and developed reducer through the vibration tests.

关键词： Three ring reducer Dynamic analysis Vibration control

NUMERICAL CALCULATIONS OF GASEOUS REACTING FLOWS IN A MODEL OF GAS TURBINE COMBUSTORS

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Chinese Journal of Aeronautics 1991年第1期6卷 26-34页

作者： Yan Chuanjun, Tang Ming, Zhu Huiling and Sun HuixianNorthwestern Polytechnical university Northwestern Polytechnical univ

This paper describes the numerical calculations of gaseous reaction flows in a model of gas turbine combustors. The profiles of hydrodynamic and thermodynamic patterns in a three-dimensional combustor model are obtained by solving the governing differential transport equations. The well-established numerical prediction algorithm SIMPLE, the modified k-ε turbulence model and k-ε-g turbulent diffusion flame model have been adopted in computations. The β function has been selected as probability density function. The effect of combustion process on flow patterns has been investigated. The calculated results have been verified by experiments. They are in remarkably good agreement.

关键词： NUMERICAL CALCULATIONS OF GASEOUS REACTING FLOWS IN A MODEL OF GAS TURBINE COMBUSTORS GAS Flow work