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A GPA diagnostic system foraeroengine applications

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航空动力学报 2007年第6期22卷 898-908页

作者： Yi-Guang Li(School of Engineering,Cranfield University,Cranfield,Bedford MK43 0AL,England) School of Engineering Cranfield University England

In this research,a GPA(Gas Path Analysis) diagnostic system enhanced with GPA Index is described for gas path sensor and component fault diagnosis.A method of measurement correction is used in order that the measurement data obtained at un-standard ambient and operating conditions can be used for diagnostic *** developed diagnostic system has been implemented into a Cranfield University gas turbine performance and diagnostic analysis software PYTHIA for gas turbine performance degradation *** developed method and software have been applied to a model aero gas turbine engine to test the effectiveness of the *** analysis shows that the developed diagnostic system can diagnose degraded sensor and components effectively using performance deviation measured at un-standard ambient and operational ***,the idea of the diagnostic approach can be applied to different gas turbine engines.

关键词：航空发动机燃气涡轮诊断系统气体分解

A Study of the Lithic Assemblage from Zhoukoudian Locality 15

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人类学学报 2002年第S1期21卷 31-52页

作者： GAOXing (Institute of Vertebrate Paleontologyand Paleoanthropology ,Chinese Academy of Sciences P .O .Box 6 43,Beijing 10 0 0 4 4,P .R .China )

Numerical Study of Phase Transition in Thermoviscoelasticity

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 207-212页

作者： The paper was received on Nov. 10 ,1997. Shaoqiang TANG (Dept. of Mech. &Engin. Sci.,Peking University,Beijing 1 0 0 871 ,P.R. China) E- mail:tangsq@*** Department of Mechanics and Engineering Science Peking University Beijing 100871 China

We study the spatially periodic problem of thermoviscoelasticity with nonmonotone structure *** pseudo- spectral method,we demonstrate numerically phase transitions for certain symmetric initial data. Without symmetry... 详细信息

关键词： phase transition. thermoviscoelasticity. mixed- type problem.

Nutrients concentration and changes in decade-scale in the central Bohai Sea

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Acta Oceanologica Sinica 2001年第1期20卷 65-75页

作者： Yu Zhigang 1,Mi Tiezhu 1,Yao Qingzhen 1,Xie Baodong 1,Zhang Jing 11 .CollegeofChemistryandChemicalEngineering ,OceanUniversityofQingdao ,Qingdao 2 6 6 0 0 3 ,China Coll. of Chem. and Chem. Engineering Ocean University of Qingdao Qingdao 266003 China

The nutrients contents and distributions are discussed briefly, based on the data obtained in 1998～1999. Besides explanation of the results,a 20 a time series data of nutrients and biological parameters for central Bohai Sea are reviewed. It is found that both concentration and relative content of nutrients have been changed dramatically. The increase of nitrogen and decrease of phosphate and silicate led to the dramatically increase of N/P ratio and the decrease of Si/N ratio. The situation of nitrogen limiting in central Bohai Sea is gradually changing to that of relative lack of phosphate and silicate. The decrease of the Huanghe River input to the Bohai Sea may be responsible for this change. These in turn may limit the growth of diatom and thus promote the development of pyrrophyta if other conditions (e.g. temperature and hydrodynamics) are suitable. We conclude that this may be the major inducement factor of pyrrophyta red tide in the Bohai Sea.

关键词： The Bohai Sea ecosystem nutrients

How To DetermiHowToDetermine The Meaning Of Strange Words In Reading Comprehension

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东华理工大学学报(社会科学版) 2000年第1期 57-60+102页

作者： HeShulin (EnglishDepartmentofFuzhouTeachersCollege ,LinchuanJiangxi 3 44 0 0 0 )

Moststudentswouldliketostoptolookupnewwordsinthedictionarywhentheyen contertheminreading ,whichwillaffecttheirguessingabilityandreadingspeed .Inthispaper , theauthorintroducesushowtodiscoverthemeaningsofstrangewordsth... 详细信息

关键词： readingcomprehension wordanalysis contextanalysis

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核酸内切酶在细胞凋亡中的作用

生物化学与生物物理进展 1997年第1期24卷 26-31页

作者：邓友平肖培根中国医学科学院中国协和医科大学药用植物研究所北京100094

核酸内切酶在形成细胞凋亡的典型特征———DNA片段化中 ,发挥着直接的重要作用 .介绍了已知的参与细胞凋亡的二价金属离子依赖性和非依赖性核酸内切酶种类 ,其中二价金属离子依赖性主要有nuc1 8、DNaseⅠ、Ca2 +/Mg2 +核酸内切酶、Ca2 ... 详细信息

核酸内切酶在形成细胞凋亡的典型特征———DNA片段化中 ,发挥着直接的重要作用 .介绍了已知的参与细胞凋亡的二价金属离子依赖性和非依赖性核酸内切酶种类 ,其中二价金属离子依赖性主要有nuc1 8、DNaseⅠ、Ca2 +/Mg2 +核酸内切酶、Ca2 +/Mn2 +核酸内切酶、DNaseγ、nuc58和nuc4 0 ;二价金属离子非依赖型主要有DNaseⅡ及类似核酸内切酶 .此外。

关键词：核酸内切酶细胞凋亡

Three dimensional diagnostic,semidiagnostic and prognostic calculations of current in the East China Sea in April of 1994

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Acta Oceanologica Sinica 2001年第1期20卷 15-28页

作者： Wang Huiqun 1,2 ,Yuan Yaochu 1,21 .KeyLaboratoryofOceanDynamicProcessesandSatelliteOceanography ,StateOceanicAdministration ,China　2 .SecondInstituteofOceanography ,StateOceanicAdministration ,POBox .12 0 7,Hangzhou 310 0 12 ,China Key Lab. Ocean Dynamic Processes S. State Oceanic Administration China Second Institute of Oceanography State Oceanic Administration PO Box. 1207 Hangzhou 310012 China

Three dimensional diagnostic,semidiagnostic and prognostic models in the σ coordinate are used to compute the current in the East China Sea with wind and hydrographic data obtained from the investigation of ocean fluxes in the East China Sea during the cruise of April *** computed results show that:the density and velocity fields and so on have been adjusted when time t ≈ 23 d, i.e.,the solution of semidiagnostic calculation has been *** quasi steady state solution also has been reached after about 60 *** the results of diagnostic calculation with those of semidiagnostic and prognostic calculations,it is found that they agree *** example,they all show that:(1)The Kuroshio flows along the shelf break of 200～1 000 m isobaths;(2)In the southeastern part of the computational region there is a stronger counter current with an anticyclonic eddy;(3)The volume transport through Section PN is about 30×10 6m 3/s and so *** there are some quantitative differences between *** example,(1)For the semidiagnostic results the Kuroshio current is stronger and clearer than that for diagnostic results and the Kuroshio width is more narrow than that for diagnostic *** shows that the semidiagnostic calculation can better reflect the topography effect;(2)In most computed region the vertical component of velocity intensifies for semidiagnostic result,especially on the shelf *** the results of semidiagnostic calculation with those of prognostic calculation,they agree qualitatively,and also agree quantitatively in the middle of computed region.

关键词： Circulation in the East China Sea diagnostic calculation semidiagnostic calculation prognostic calculation

ILLUMINATION AND EXPOSITION OF A CONVEX n-DIMENSIONAL BODY DEPENDING ON ITS SHARPNESS

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Acta Mathematica Scientia 2002年第2期22卷 189-198页

作者： Boris V. Dekster Mathematics, Mount Allison University, Sackville, N.B. EOA 3C0, Canada Mathematics Mount Allison University Sackville N.B. E0A 3C0 Canada

A convex n-body C is said to be exposable to a set D of a few directions if there is a linear transformation L : En → En such that L(C) arid each body isometric to L(C) is illuminated by D. Denote by En the minimum integer such that each C is exposable to a (fixed) set D of cardinality En. An upper bound for En is established here.

关键词： Covering illumination Hadwiger conjecture

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氨酰-tRNA合成酶对tRNA的识别

生物化学与生物物理进展 1997年第1期24卷 2-7页

作者：李勇李彤王恩多中国科学院上海生物化学研究所

氨酰 tRNA合成酶 (aaRS)与tRNA的相互作用保证了蛋白质生物合成的忠实性 .氨酰 tRNA合成酶对tRNA识别的专一性依赖于aaRS特定的催化结构域和tRNA分子特异的三级结构构象 .反密码子和接受茎 (包括 73位 )在大多数aaRS对tRNA分子的识别过... 详细信息

氨酰 tRNA合成酶 (aaRS)与tRNA的相互作用保证了蛋白质生物合成的忠实性 .氨酰 tRNA合成酶对tRNA识别的专一性依赖于aaRS特定的催化结构域和tRNA分子特异的三级结构构象 .反密码子和接受茎 (包括 73位 )在大多数aaRS对tRNA分子的识别过程中起着关键作用 ,其他部位如可变口袋、可变 (茎 )环等。

关键词：氨酰-tRNA 合成酶 tRNA 识别