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SOME CONVERSE RESULTS ON ONESIDED APPROXIMATION: JUSTIFICATIONS

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Analysis in Theory and Applications 2003年第3期19卷 280-288页

作者： WangJianli ZhouSongping ShaoxingArtsandScienceCollge China zhejianginstituteofscienceandtechnology China

The present paper deals with best onesided approximation rate in L p spaces n(f) L p of f∈C 2π. Although it is clear that the estimate n(f) L p≤C‖f‖ L p cannot be correct for all f∈L ... 详细信息

The present paper deals with best onesided approximation rate in L p spaces n(f) L p of f∈C 2π. Although it is clear that the estimate n(f) L p≤C‖f‖ L p cannot be correct for all f∈L p 2π in case p<∞, the question whether n(f) L p≤Cω(f,n -1) L p or n(f) L p≤CE n(f) L p holds for f∈C 2π remains totally untouched. Therefore it forms a basic problem to justify onesided approximation. The present paper will provide an answer to settle down the basis.

关键词： onesided approximation L p space modulus of continuity

ON A CLASS OF BESICOVITCH FUNCTIONS TO HAVE EXACT BOX DIMENSION: A NECESSARY AND SUFFICIENT CONDITION

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Analysis in Theory and Applications 2004年第2期20卷 175-181页

作者： ZhouSongping HeGuolong zhejianginstituteofscienceandtechnology ChinaNingboUniversityChina ZhejiangNormalUniversity China

This paper summarized recent achievements obtained by the authors about the box dimensions of the Besicovitch functions given bywhere 1 tends to infinity as k→∞ and λk satisfies λk+1/λk≥λ>1. The results show thatis a necessary and sufficient condition for Graph(B(t)) to have same upper and lower box dimensions. For the fractional Riemann-Liouvtlle differential operator Du and the fractional integral operator D-v, the results show that if A is sufficiently large, then a necessary and sufficient condition for box dimensionof Graph(D-v(B)), 0 < v < s - 1, to be s - v and box dimension of Graph(Du(B)), 0 < u < 2 - s, to bes + u is also lim.

关键词： Weierstrass function Besicovitch function fractal dimension box dimension Hard- mard condition

MODELING AND PERFORMANCE ANALYSIS FOR THE SERIAL AND PARALLEL PRODUCTION SYSTEM BASED ON GSPN

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Chinese Journal of Mechanical Engineering 2004年第3期17卷 427-432页

作者： GaoJianhua HuXudong YangRuqing SchoolofMechatronicEngineering ZhejiangInstituteofScienceandTechnologyHangzhou310033China ResearchInstituteofRobotics ShanghaiJiaotongUniversityShanghai200030China

Differed from the existed applications of generalized stochastic Petri net(GSPN) theory in machine-tool manufacturing system, reliability computation of FMS, testabilityparameters determination and fault analysis, a new idea of applying GSPN to model and performanceanalysis for the serial and parallel production system is proposed. And one typical discrete eventdynamic system (DEDS), turner-unit of palletizing system, is taken as a real case to research. Basedupon the established GSPN models, the working performances of serial and parallel layout arecompared. Furthermore, their differences of working mechanisms including feeding mechanism,coordinating mechanism and monitoring mechanism are discussed. Thus the theoretical basis which ishelpful to appraise layout plan and its reasonableness is provided. Meanwhile, the research resultsshow that parallel layout is more advantageous to greatly improve the operational speed ofproduction system than serial one.

关键词： Serial and parallel production system Generalized stochastic Petriv net Discrete event dynamic system Palletizing system

State Fusion Estimation for Multilevel Multisensor System

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Journal of Systems Engineering and Electronics 2003年第4期14卷 77-83,89页

作者： JinXuebo SunYouxian CollegeofInformaticsandElectronics ZhejiangInstituteofScienceandTechnologyHangzhou310033P.R.China NationalLaboratoryofIndustrialControlTechnology ZhejiangUniversityHangzhou310027P.R.China

Based on the single sensor Kalman filtering equations, this paper presents two-level and three-level optimal centralized and distributed estimation algorithms for hierarchical multisensor systems. The solution shows that when the correlated matrix, the mean of noise, the control input, and the measurement error are all zero, the result in this paper turns out to be the standard algorithm discussed. Simulation shows that the mean of noise, the control input, and the measurement error will not change the estimation covariance and the estimation covariance fluctuates greatly when the cross-correlated matrix is similar to the covariance of process noise.

关键词： data fusion hierarchical estimation multilevel filtering correlated noise.

Non-Noether Conserved Quantity for Relativistic Nonholonomic System with Variable Mass

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Communications in Theoretical Physics 2005年第2期43卷 197-200页

作者： QIAOYong-Fen LIRen-Jie MAYong-Sheng DepartmentofMechanicalEngineeringandAutomation ZhejiangInstituteofScienceandTechnologyHangzhou312207China／／FacultyofScienceLaiyangAgriculturalCollegeLaiyang265200China FacultyofScience LaiyangAgriculturalCollegeLaiyang265200China EngineeringCollege NortheastAgriculturalUniversityHarbin150030China

Using form invariance under special infinitesimal transformations in which time is not variable, the non-Noether conserved quantity of the relativistic nonholonomic system with variable mass is studied. The differential equations of motion of the system are established. The definition and criterion of the form invariance of the system under infinitesimal transformations are studied. The necessary and sufficient. condition under which the form invariance is a Lie symmetry is given. The condition under which the form invariance can be led to a non-Noether. conserved quantity and the form of the conserved quantity are obtained. Finally, an example is given to illustrate the application of the result.

关键词： analytical mechanics relativity nonholonomic system variable mass non-Noether conserved quantity

Non-Noether Conserved Quantity of Nonholonomic System Having Variable Mass and Unilateral Constraints

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Communications in Theoretical Physics 2004年第6X期42卷 801-804页

作者： QIAOYong-Fen LIRen-Jie MAYong-Sheng DepartmentofMechanicalEngineeringandAutomation ZhejiangInstituteofScienceandTechnologyHangzhou310027China//PhysicsTeachingDivisionLaiyangAgriculturalCollegeLaiyang265204China// PhysicsTeachingDivision LaiyangAgriculturalCollegeLaiyang265204China EngineeringCollege NortheastAgriculturalUniversityHarbin150030China

Using the Lie Symmetry under infinitesimal transformations in which the time is not variable, the nonNoether conserved quantity of nonholonomic system having variable mass and unilateral constraints is studied. The differential equations of motion of the system are given. The determining equations of Lie symmetrical transformations of the system under infinitesimal transformations are constructed. The Hojman's conservation theorem of the system is established. Finally, we give an example to illustrate the application of the result.

关键词：质量变化单边约束不完整系统决策函数解析力学

Non-Noether symmetrical conserved quantity for nonholonomic Vacco dynamical systems with variable mass

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Chinese Physics B 2004年第11期13卷 1790-1795页

作者：乔永芬李仁杰赵淑红 DepartmentofMechanicalEngineeringandAutomation ZhejiangInstituteofScienceandTechnologyHangzhou310027China FacultyofScience LaiyangAgriculturalCollegeLaiyang265200China EngineeringCollegeofNortheastAgriculturalUniversity Harbin150030China

Using a form invariance under special infinitesimal transformations in which time is not variable, the non-Noether conserved quantity of the nonholonomic Vacco dynamical system with variable mass is studied. The differential equations of motion of the systems are established. The definition and criterion of the form invariance of the system under special infinitesimal transformations are studied. The necessary and sufficient condition under which the form invariance is a Lie symmetry is given. The Hojman theorem is established. Finally an example is given to illustrate the application of the result.

关键词： variable mass nonholonomic constraint Vacco dynamical system non-Noether con served quantity

FRICTION PROPERTIES OF OIL-INFILTRATED POROUS AAO FILM ON AN ALUMINUM SUBSTRATE

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 249-253页

作者： C.X.Jiang J.P.Tu S.Y.Guo M.F.Fu X.B.Zhao DepartmentofMaterialsScienceandEngineering ZhejiangUniversityHangzhou310027China／／DeparunentofMechanicalandElectronicEngineeringNanchangUniversityNanchang330029China DepartmentofMaterialsScienceandEngineering ZhejiangUniversityHangzhou310027China DepartmentofMechanicalEngineering ZhejiangInstituteofScienceandTechnologyHangzhou310012China DepartmentofMechanicalandElectronicEngineering NanchangUniversityNanchang330029China

The porous anodic aluminum oxide (AAO) film on a pure aluminum substrate was pre pared by a two-step anodization in a 0.3M oxalic acid solution and pore-enlargem ent treatment in the phosphoric acid aqueous solution at 50℃. The diameter of h ighly ordered pore on the AAO film was about 90nm, and the thickness of the AAO film was 3μm. The mineral oil was infiltrated in the ordered nanometer sized po res of AAO film on an aluminum substrate due to the capillarity effect. The fric tion coefficient was measured using a ball-on-disk tribotester. The tests were c onducted at loads range from 490 to 2450mN and at sliding velocities between 0.1 and 0.5m·s-1. Oil infiltration in porous AAO film modified friction and consid erably improved the wear resistance. As compared to the porous AAO film, the oil -infiltrated specimen had low friction coefficient. With increasing the applied load and sliding velocity, the friction coefficient of the oil-infiltrated film decreased. It indicates that the oil-infiltrated AAO film produced a new way to modify the friction and wear of aluminum alloy.

关键词： friction coefficient oil-infiltrated AAO film aluminum substrate

FRACTIONAL INTEGRALS WITH VARIABLE KERNELS ON HARDY SPACES

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Applied Mathematics(A Journal of Chinese Universities) 2003年第4期18卷 461-466页

作者： ZhangPu DingYong Dept.ofInformationandComputingScience ZhejiangInstituteofScienceandTechnologyHangzhou310033China Dept.ofMath. BeijingNormalUniversityBeijing100875China

The fractional integral operators with variable kernels are *** is proved that if the kernel satisfies the Dini-condition,then the fractional integral operators with variable kernels are bounded from Hp(Rn) into Lq(Rn... 详细信息

关键词： fractional integral variable kernel Dini-condition Hardy space