Abstract:System identification is the theory and methods of establishing the mathematical models of systems.This paper discusses some basic issues involved in system identification,including the identification accuracy,the identification methods,the input signal design,the parameter identifiability and system identifiability,the open-loop identifiability and closed-loop identifiability,the identifiability and the controllability and observability,the identifiability and the input signal,and the excitation signal and the excitation conditions relate to the convergence of identification methods,and the convergene theorems of some typical identification algorithms.

Abstract:The satellite remote sensing data of the Yangtze River Delta in 1993 and 2004 were taken to analyze land use changes and urban growth of Nanjing,Shanghai,and Suzhou-Wuxi-Changzhou regions in the Yangtze River Delta.The land surface temperature (LST) in 2004 was selected as the indicator to estimate the difference of thermal characteristics between urban and rural area.The relationship of spatial characteristics of LST and types of land-use had also been analyzed.Conclusions were drawn as follows:the changes of the urbanized and cultivated lands were great during the past 11 years.The amount of cultivated land was decreasing,while the amount of construction and building land was rapidly increasing.The dynamic degrees of construction and building land among Shanghai,Suzhou-Wuxi-Changzhou and Nanjing regions were 204.0%,354.3% and 99.2%,respectively.The expansion of construction land was the largest in Suzhou-Wuxi-Changzhou region.The LST of urban area was the largest among all land-use.The seasonal LST differences between urban and rural regions were maximum in winter andminimum in autumn.

Abstract:Due to its different acquisition methods,meteorological data has characteristics of various kinds,formats and numerous data amount.Besides observation data,radar data,satellite image,meteorological data includes derivativeouts products,such as numerical forecast,radar rainfall estimation,typhoon track prediction,etc.With its rapid development,GIS has played an important role in meteorological field,and the combination of GIS and meteorological application model is becoming more and more close.However,the diversification of the meteorological data's storage format,storage method and data display,as well as the widely involved field of meteorological service industry,cause difficulty in the widespread use of GIS in meteorological domain.In this study,meteorological data were divided into discrete data,grid data and element data.On this basis,a meteorological database,includes meteorological information,social information,fundamental geographic data and meteorological spatial information,were put forward,and the general structure,display and processing of meteorological data were described in detail.Finally,a GIS-based treatment scheme of data management and expression was proposed,which has been used in meteorological departments now and can meet meteorological service requirement.

Abstract:In order to improve the quality of meteorological data and provide reliable data sources for weather forecasts and other meteorological applications,the paper presents a quality check method of meteorological observational data based on rule engine.The method is able to decode and translate accurately the routine meteorological message in real time.It can check and revise the message which does not meet the norms published by the WMO and the CMA.It also has flexible ability in man-machine interaction,by which to satisfy the developing and changing requirements about meteorological observational data.This method may replace the traditional quality control method,which use the meteorological extreme value examination.It can enhance the processing efficiency of real-time data,and can also promote the accuracy of result produced by meteorology applications.The practical applications prove that this method is effective and efficient.

Abstract:Electric field mills play an important role in measuring near-ground electric field,whose observation accuracy is prone to be influenced by many factors.Based on experiments with upright and inverted probes,this paper demonstrates that the orientationouts of the probes makes no difference to the results,while inverted probes couldminimize impacts of charged raindrops in the perennial and all-weather observation.In addition,it puts up a calibration method to get the electric field value on the ground in different weathers and different amplitudes of atmospheric electric field,which can eliminate impacts of the surroundings to realize uniformity and comparability of data from multiple sites.

Abstract:The basic method of collecting data for benefit evaluation of public meteorological services is public questionnaire."Shadow Price" is one of the most frequently used methods in benefit evaluation of public meteorological services.Based on 10 430 valid questionnaires from public meteorological service centre of CMA,the benefits of public meteorological services in Beijing,Shanghai and Guangzhou were compared and analyzed using "Shadow Price" method.The results showed that the most significant effect of public meteorological services on the society and economics development was in Beijing,followed by Guangzhou and the last was in Shanghai.Parameter selection of "Shadow Price" and quality of the questionnaires are the two key factors influencing the benefit evaluation result of the public meteorological services.

Abstract:For the complex dynamics modelling process,low computational efficiency accuracy of large scale multibody system,an efficient and precise dynamics modelling method is proposed based on spatial operator algebraic.The method combines transformation operators,which include recursive relations of system topology structure,motion and strength,with recursive dynamics of Newton-Euler through the dynamics variables expressed by screw.This method achieves forward backward recursion of generalized velocity,acceleration force,strength and mass,and avoids cross operation and unnecessary integrals.It is valuable in scientific and engineering aspects for its brief modeling process,clear physical meaning,and suitability in computer programming and calculation.An example is given to verify this method.

Abstract:Edge detection is one of most important fields in computer vision,and lots of algorithms have been proposed by former scholars.Based on properties of image and detector,and taking relevances as criterion,this paper proposes an algorithm which use genetic algorithm to select optimal wavelet transform scales to form an adaptive Gaussian wavelet scale space.By fusing image's edges detected at different scales in this scale space,image will be improved in edge details and noise immunity.Experiments show that this adaptive scale wavelet algorithm has advantage in terms of noise removing and corner points positioning over Canny algorithm,single-scale wavelet algorithm,binary scale wavelet algorithm or multi-scale wavelet a algorithm.

Abstract:Currently local area network is one of the most prevalent networks.There are multiple virtual local networks and many switches in real local area network,thus it is necessary to implement uniform virtual local area network management and redundant link setting.Trunking protocol is applied to realize the consistency of virtual local area network configuration in view of uniform management.Setting redundant links will bring about loops and broadcast storm,so spanning tree protocol is applied to avoid loops for smooth communication.Simulation can be used for configurating network protocol and realizing communication under lack of experiment funds.DynamipsGUI was applied to simulateminiature local area network,which simplified the network analysis and design.The simulation process was detailed through the configuration of virtual local area network trunking protocol and spanning tree protocol.In virtual environment,application of multiple network protocols is helpful to network configuration learning,and accords with the real network environment as well.

Abstract:Power grid is an important factor in the development of distributed energy,so the research on the relationship between them is very necessary.If Win-Win cooperation for power supply in the region can be achieved,it will provide an effective way to relieve the energy crisis and the pressure of power supply.In this paper,distributed energy systems and power grid in a certain region are Abstracted as two types of Agent by using the approach of Agent modeling.The model of regional cooperation is established to simulate the decision-making behavior with the guidance of expected annual profit.By the iterative process of "adjusting the strategy and calculating the profit ",the simulation illustrates the boundary conditions and the adjustment track of win-win cooperation.Finally an example of the Energy Center of Shanghai Pudong International Airport is put forward to prove the effectiveness of the method.

Abstract:This paper explains that refraction reflection coefficients will change at different time when the lightning wave comes,as a result,the shape of lightning wave will change when they get through the series inductance.Voltage amplitude of lightning wave will reduce as long as the gradient of lightning wave decreases.According to this basic principle,a large scale of tests were carried out on ICGS.Comparative analysis shows that the residual voltage could be reduced by adding of the series inductance,thus enhance the tolerance capacity and improve the protection effect of multi-stage SPD.The application of series inductance in SPD is of great significance to the lightning protection in the power distribution system.

Abstract:In this article,the oscillation of certain high-order neutral hyperbolic functional partial differential equation is considered.By using Green formula,Jensen inequlity,and eigenvalue method,we obtain some new oscillatory criteria on two boundary conditions that ensure the oscillation of solutions.The results obtained extend and improve a number of existing criteria in the literature.

Abstract:For a ring endomorphism α,we generalize the concept of symmetric rings,introduce the notation of α-symmetric rings and investigate some properties of them.