首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
High precision parameter estimation is very important for control system design and compensation. This paper utilizes the properties of chaotic system for parameter estimation. Theoretical analysis and experimental results indicated that this method has extremely high sensitivity and resolving power. The most important contribution of this paper is apart from the traditional engineering viewpoint and actualizing parameter estimation just based on unstable chaotic systems.  相似文献   

2.
IntroductionMostoftheenterprisesmightusesomekindsofisolatedITsystems ,suchasEnterpriseResourcePlanning(ERP )systems,CustomerRelationshipManagement(CRM )systems,SupplyChainManagement (SCM )systems,OfficeAutomation (OA )suitesandsoon ,toautomatedistinctbusinesspractices .Thesesystemsoftencoexistwithawidevarietyofin houseapplications[1] .Inordertoimprovebusinessbyautomatingbusinessprocessesthatspantheseisolatedsystems,theenterpriseneedstointegratetheisolatedsystemsandapplicationswithEnt…  相似文献   

3.
The dewaterability of activated sludge conditioned by chitosan flocculant was studied. The effects of chitosan characteristics such as molecular weight, degree of deacetylation, and dose on the dewaterability were investigated. The sludge dewaterability is evaluated in terms of specific resistance to filtration, residual turbidity of supernatant, moisture content of cake, and settling rate. Sludge dehydrating behaviors conditioned with CTS, PAM and PAC flocculants were compared. The conditioning was also carried out with dual flocculants in two stages. It is found that the sludge conditioned with CTS has better dewaterability than that with PAC. The optimum conditions with chitosan are: dose 0.8 - 1.2 g per 100 g dry cake, molecular weight 300,000, and degree of deacetylation 70%. The conditioning in two stages with dual flocculants is found to be more effective than that with single flocculant.  相似文献   

4.
The Application of Tea Dyeing to Silk   总被引:2,自引:0,他引:2  
Vegetable dyes are eco-friendly throughout the full production process. A study is conducted with the purpose of assessing the properties of dye extracted from green tea, black tea and the tea tree cultivated and used in Jiang Nan area of China. The extracted dyes are applied with and without mordants on silk fabric and the dyeing properties are evaluated.  相似文献   

5.
Cathodoluminescence (CL) image analysis of zircon is a key step of mineral micro?area compositional investigation and U-(Th)-Pb dating. We introduce a system consisting of field emission ESEM and high performance cathodoluminescence. This system has obvious advantages in imaging resolution and CL spectrum. We acquired some zircon CL images and spectra to demonstrate the ability of this system. Our results show that this system has a great potential application to characterize and identify the genesis of zircon.  相似文献   

6.
0 IntroductionTheStokesequationhaswide rangingphysicalbackgrounds.Tillnow ,ManypapersfornumercialsolutionsofStokesequationhavebeenpresented .Brezzietal[1] havealreadyusedthreestablizedmixedmethodsandobtainedtheapporximatesolu tionoftheStokesequationandthee…  相似文献   

7.
The structure of ZNF191(243-368), the zinc finger region protein of zinc finger protein ZNF191, and its structural change upon thermal and EDTA-induced denaturation were investigated by the Raman spectroscopy. It was demonstrated that the coordination between Zn^2 and His/Cys in ZNF191(243-368) is the essential factor to the stability of zinc finger, which plays an important role in maintaining the hydrophobic core and the secondary structure in zinc finger, and the Raman spectroscopy is a powerful tool for investigating the structure of ZNF191(243-368).  相似文献   

8.
Evidence for the existence of primitive life forms such as lichens and fungi can be based upon the formarion of oxalates. Oxalates are most readily detected using Raman spectroscopy. A comparative study of a suite of natural oxalates including weddellite, whewellite, moolooite,humboldtine, glushinskite, natroxalate and oxammite has been undertaken using Raman spectroscopy. The minerals are characterised by the Raman position of the CO stretching vibration which is cation sensitive. The band is observed at 1468 cm^-1 for weddellite, 1489 cm^-1 for moolooite, 1471cm^-1 for glushinskite and 1456 cm^-1 for natroxalate. Except for oxammite, the infrared and Raman spectra are mutually exclusive indicating the minerals are bidentate. Differences are also observed in the water OH stretching bands of the minerals. The significance of this work rests with the ability of Raman spectroscopy to identify oxalates which often occur as a film on a host rock. As such Raman spectroscopy has the potential to identify the existence or pre-existence of life forms on planets such as Mars.  相似文献   

9.
The rapid development of computer modeling in recent years offers opportunities for materials preparation in a more economic and efficient way. In the present paper, a practicable route for research and development of advanced materials by applying the visual and quantitative modeling technique on the mesoscale is introduced. A 3D simulation model is developed to describe the microstructure evolution during the whole process of deformation, recrystallization and grain growth in a material containing particles. In the light of simulation optimization, the long-term stabilized fine grain structures ideal for high-temperature applications are designed and produced. In addition, the feasibility, reliability and prospects of material development based on mesoscale modeling are discussed.  相似文献   

10.
This paper presents a nonlinear finite element method to resolve the problem of the nonlinear contact between the drillstring and hole by using a Multi-directional Contract Gap Element(MCGE) contacting at approprizte positions in each beam element.The method was successfully applied to the Daqing Oil Field GP1 well.It was shown that the drillstring‘s contact resistance at any well depth could be obtained by calculations and that as the enor in the calculation of the hole top load is below 10%,the calculation result can provide theoretical basis for the design and operation of drillstrings.  相似文献   

11.
The air-flow's states and ways acted on the technological process of chemical fiber are summed up, which includes chip drying, spinning quenching as well as airjet texturing (air texturing, tangling texturing and bulked continuous filament (BCF)),and the effect of air-flow on the process and quality of chemical fiber is studied,and the action of mechanics and heat on the bulked continuous filament are calculated.  相似文献   

12.
The paper discussed the synthesis and application of sodium benzoylthioglycollate (BTG) to cotton cellulose. The main product was proved to be BTG. Dyeing substantivity of modified cotton fibre by BTG with disperse dye were improved. The effect of modification conditions, such as the property of alkali and its using amount, curing temperature and time were discussed. Colour yield and resistance to wash fastness were also measured.  相似文献   

13.
Hamiltonian of an O3 molecule is classicized by using coherent states, and its potential energy surface is obtained. The surface and the contours are plotted. The calculated force constants and dissociation energies are in good agreement with experimental values.  相似文献   

14.
A nonlinear optimization method is applied to sensitivity analysis of a numerical model. Theoretical analysis and numerical experiments indicate that this method can give not only a quantitative assessment whether the numerical model is able to simulate the observations or not, but also the initial field that yields the optimal simulation. In particular, when the simulation results are apparently satisfactory, and sometimes both model error and initial error are considerably large, the nonlinear optimization method, under some conditions, can identify the error that plays a dominant role.  相似文献   

15.
This paper introduces the pragmatic basis of politeness principle and analyzes the practical application of politeness principle in College English teaching,according to Leech's six maxims of politeness principle.  相似文献   

16.
A kind of PH gradient microfluidic chips through soft-lithography microfabrication for isoelectric focusing (IEF) and high performance liquid chromatography (HPLC) is introduced here. These pH gradient chips have the advantages such as easy fabrication, controllable pH range and precision, isoelectric focusing and separation at the same time, low voltage for isoelectric focusing, and time stable pH gradient. This method has potential application to sample preparation, separation and analysis of microfluidic chips.  相似文献   

17.
The influence of gravity waves on the sodium layer is studied by using a linear photochemical-dynamical coupling gravity wave model. The model includes the back-ground photochemistry and the photochemical reactions in the sodium layer. The amplitude and phase difference of the response of sodium mixing ratio to gravity waves are calculated. The results indicate that the lower part of sodium layer is the most sensitive region responding to gravity waves. The perturbation of sodium mixing ratio is in phase with temperature in the lower part of the layer. However, it is out of phase with temperature fluctuation in the upper part.  相似文献   

18.
19.
The assessment of water security is an important content in the security management of water resources due to the fact that the state of water security directly affects both the sustainable development of regional economy and the improvement on the living quality of mankind. Grey associative analysis is introduced and applied to assessment of water security on the basis of grey characteristics of the assessment index system of water security. As a case study shows, grey associative analysis is used for evaluating water security of some provinces in China, and the satisfactory assessment results are obtained. The sequence of provinces in China with regard to water security from good to poor is obtained and, moreover, the water security level of each region is also confirmed. The results obtained accord with the actual state of each region. They are of practical significance and can be used to guide the management of regional water security and a sustainable development of the economy therein. At the same time, the results demonstrate that grey associative analysis provides a new method for assessing water security  相似文献   

20.
0IntroductionLand resourceis the material basis of people’s existence.Land protectionis a persistent national problembecausethat it is serving national sustainable development.Moreover,land evaluation and land gradation are of great i mportance inguiding decisions onland uses andland explorations.Shortageof land resource becomes serious,which attracted the specialattention and recognitionin various countries.And so,manyscholars triedtofind novel approaches of landresource evalua-tion.Kalogir…  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号