Letπbe a set of primes number.Isaacs first proposed the concept of Bπ′-character and successed in the extension of Fong-Swan theorem to characterπ-theory.Bπ′-character can be considered as the extension of Brauer character.Based on Isaacs work,Mπ-group is definited.It is proved that if Gis finiteπ-seperable group,then Gis Mπ-group if and only if a direct factor of Gis Mπ-group.
Based on the data the exchange rate from 2005 August to 2014 July,the vector auto regression model was constructed to study the effect of nominal exchange rates on the import price index and the consumer price index.Research results show that the effect of RMB nominal effective exchange rate on the import price index and the consumer price index is partial pass-through,and a certain time lag.The passthrough effect of nominal effective exchange rate of RMB to import price index is bigger than the consumer price index.
针对资源约束项目计划的内在稳健性受多种因素影响的问题,本研究采用16种优先规则,对Kolisch的j30算例集中的480个算例分别制定项目计划,计算出各项目计划的最少关键序列总数、资源使用效率及项目计划工期比项目最短工期长出的百分比L,并通过仿真得到各项目计划的内在稳健性值;同时应用多元统计方法,建立项目计划内在稳健性与各影响因素之间的回归方程。统计检验结果表明,回归方程是显著有效的,最少关键序列数、资源使用效率与内在稳健性呈负相关,项目计划的工期比项目的最短工期长出的百分比L与内在稳健性呈正相关;交叉项检验结果表明,关键序列较多时,L的增大可以有效地提高项目计划的稳健性,这与实际状况一致。该研究可为具有稳健性项目计划的制定、预测和控制提供决策依据。
To better determine parameters of defectsu0027location and the size in the concrete,using the method of IART,a new weighted CG algorithm,its weight is added on the imaging unit instead of equation,is proposed.The way of obtaining weighting value and initial iterative value in iterative process of curve tomography is given.The results of simulation and concrete examples show that accuracy of computation and the quality of image reconstruction can be improved by Weighted CG algorithm
In order to research the effect factors for county financial development in Shandong Province,choosing the data form seventy-nine counties and county-level cities in 2008—2012,the factor analysis was used to extract four principal-component factors such as economic development factor,industry structure factor,urbanization factor,urban-rural income gap factor.By the comparison of similarity and difference of the principal-components factors extracted in three regions,results show that county economic development is the main factor of county financial development in Shandong province,and the influence of industry structure,urbanization and urban-rural income gap in three regions isdifferent.
For the three-phase voltage-type PWM converter using energy shaping and port controlled Hamiltonian to design controller,the power model of three-phase PWM rectifier is established in this paper and the PCH controller of rectifier is designed,and it changes damper by the tracking-differentiator to realize the variable damping control.Simulation results show that when the value of damper injection is small,the system starts slow.While the injection is too big,it induces a lot of the output voltage overshoot.Therefore,by selecting appropriate input function and parameter values,damper values can be achieved by expectations.The method can make rectifier run with unit power factor,the output voltage quickly reaches the set value and keeps stable to meet control requirements,and provides a new approach for the power electronic converter.
In view of non-salient pole permanent magnet synchronous motor using state errors in PCH only the location of the system response having the problem of steady-state errorwhen system exists load torque disturbance,this paper puts forward a method of combining the state error and the L2 gain.Firstly based on dq coordinate system was established by the PCH system mathematical model of permanent magnet synchronous motor.Secondly using the stateerror PCH and L2 gain theory based on maximum torque/current principle,we determine the equilibrium of the system when the load torque is known.Finally using the state error PCH system theory,we calculate the controller of the system and usingthe state error PCHsystem theory and the L2 gain principle,we calculate the controller when the presence of the system load torque disturbance.Through the Matlab/Simulink simulation,the simulation results show that the system contains the L2 gain,can quickly arrive at a given location,and can effectively restrain the load torque disturbance,reduce the static error.The study shows that the L2 gain and state error PCH can inhibit the combination of load torque disturbance,and so the controller has a certain practical value.
A 3Dracing game was designed by means of a new cross platform development toll—XNA Game Studio.The method of the collision detection in game was analyzed.A component model that surrounded by combinational balls was presented.Through reloading the processing method of framework class library file under the different scenes,the collision detection of the XNA camera was realized in 3Dgame.
In order to solve the low heat transfer efficiency and the scaling problem in a tube,numerical simulation of turbulent pulsating flow and heat transfer was done with standard k-eturbulent model.The flow characteristics and the regional boundary conditions were given.And then it analyses the influence of the oscillation flow to the surface heat transfer coefficient and the wall shear stress.The results show that when the fluid is unclean,there would be impurities deposit in the wall of the tube and produce fouling resistance and severely decrease the heat transfer efficiency.The oscillation flow can make the wall shear stress increased dramatically.The wall shear stress can not only block the impurities deposit and keep the heat transfer equipment in a high heat transfer efficiency condition but also can impact the schmutzband make them fall off from the wall of the tube which can decrease the fouling resistance and improve the heat transfer efficiency.The oscillation flow has a good preventing and removing fouling effect when the fluid is unclean and can improve the heat transfer efficiency and keep the heat transfer equipment in a high heat transfer efficiency condition.This research provides theoretical reference for solving the deposit problem in the process of unclean water heat transfer.
Aiming at the problems of a running power system such as the high voltage or low voltage of bus bars,a typical power system model with three generators and nine nodes is adapted and its simulating model is set up.Theoretical analysis is conducted about the factors influencing the amplitude and angle of voltage and the methods are found out for the voltage adjustment aiming to these factors.Then the simulation result is testified by the ETAP.It is shown that the mainly influences the angle of voltage and the influences the amplitude of the voltage.Therefore,the bus voltage can be adjusted by changing the arrangement of the and the taps of the transformer to improve the quality of the bus voltage.The research provides theoretical basis for the design and operation of power system.
In order to realize the communication between Android client and C++server on the mobile intelligent control system,which can control the mosaic screen,a Socket communication between Android and C++ Server based on TCP will be presented in this paper.It has realized the command interaction,Data transmission between the server and client.It also realized the image transmission function based on Base 64 Coding technology.The XML technology has been introduced to transfer the data.The technology of DOM4 Jhas been used to parse the XML data.The using of encryption algorithm has guaranteed the system security in the process of Wireless communication.
It is important to study the stability issue for time-delay systems as time-delay is often the main cause of instability and poor performance of dynamic systems.This paper is concerned with the problem of delay-dependent stability for neutral systems with interval time-varying delays.Based on the LyapunovKrasovskii stability theory,a new type of augmented Lyapunov-Krasovskii functional is constructed and a new delay-dependent stability criterion is established in terms of linear matrix inequalities.The Wirtingerbased integral inequality and the reciprocally convex method are used to deal with the delay term.A numerical example is given to illustrate the improvement of the upper bounds of time-varying interval and the effectiveness of the present results.
In order to improve the adhesion performance between Marine anti-fouling paint and anti-corrosive primer and anti-fouling paint bactericidal performance,in this paper,the side chain containing triadimenol disinfectant bactericidal resin 1 and bactericidal resin 2 were prepared by using self-made ester monomers and its structures were confirmed using infrared spectrometer;And with the prepared anti-fouling resin for the based resin,two kinds of anti-fouling coatings were prepared,and testing its various performance respectively.Results show that the preparation of 2 bactericidal resin and its mixed with bactericidal resin 1 of anti-fouling resin,the epoxy coating has a good bonding performance;The preparation of anti-fouling coatings has good anti-fouling and polishing performance;The problem which triadimenol was lose in the form of additives in the Marine coatings application of loss was solved;term anti-fouling controllable can be adjusted by the proportion of the dosage of the two kinds of resin.The study of new type of Marine anti-fouling coatings is of great significance.
The stable crystal structure of Au-rich Au3 Si systems was predicted using agenetic algorithm in combination with first-principles calculations.The results show that the lowest-energy structure is an Au6Si2 cell with space group Amm2.The newly discovered structure is further shown to be energetically stable.The properties of Au6Si2 crystal were compared with single phases of pure Au and pure Si.Density of States and band structure show that the d electrons of Au atom hybridize with the p electrons of Si atom,lowering the p electronu0027s energy level,reducing the band gap and even vanishing.The Au6Si2 crystal can exist thermodynamically due to its larger entropy than that of pure Au or pure Si phase.
This paper focuses on the problems of warehouse management process and different warehouse management level,and optimized methods of warehouse management in the industrial seedling nursery process are developed based on warehouse division manage methods.The stock products in the warehouse can be divided into three groups.They are raw seeds,being cultivated crops and finished crops.According to different type of the warehouse material,the time-driven method,the economic method and the eventdriven compensation method was suggested.In addition,the classified and optimized methods in the nursery industry were suggested in this paper.The application shows that these methods mentioned in this paper can dramatically solve the actual problem in the warehouse management process.Result mentioned in this article can be applied to any other agriculture manufacturing industry.
In view of the leakage and friction problems on the excavator load sensitive pump hydraulic system,this paper establishes the mathematical model of load sensitive valve work,based on the principle of load sensitive.At the same time using AMESim software,the establishment of load sensitive pump hydraulic system simulation model,and the simulation analysis was carried out on the LS.The simulation results show that:by changing the control system of the load sensitive valve spring stiffness,and his mouth shape,diameter of the valve core and valve core quality,can make the system more and more quickly reach the steady state,and small overshoot quantitative change,gradually reduce the oscillation frequency;different mouth shapes different flow gain;When the spool diameter is 6mm,the outlet pressure dynamic curve is the most stable,the overshoot is the most ideal,which coincides with the most cases;When the valve core quality is set to 0.5kg,system response is fast,and the pressure fluctuation is more ideal.The research has a certain reference value on the designing,using,and maintaining of the load sensing pump.
Mathematical model of binocular vision method for measuring the contact line geometry is established.The binocular measurement system structure parameters and camera optical parameters and the measurement error and the relationship between the sensitivity were systematically analyzed,and simulated by use of MATLAB.The results show that the binocular visual system sensitivity to changes in contact wire height is much lower than the sensitivity of the stagger values change,so the measuring error of contact wire's height is far more than the error of stagger value.In order to raise the measuring accuracy for both height and stagger value,one method is to achieve sub-pixel resolution;the second is appropriate to increase 2L,the distance between the two cameras CCD photosensitive surface center,to increase the angle of camera optical axis relative to the vertical plane,and to increase the camera focal length to improve measurement sensitivity,reduce the measurement error.
Yttrium oxide(Y2O3)dielectric films were grown on heavily-doped silicon(100)substrates by sol-gel process.This paper describes the effects of annealing temperatures on the microstructural and electrical properties of sol-gel derived Y2O3 thin films.These thin films were annealed at different temperature,ranging from 300℃ to 600℃,for one hour.The X-ray diffraction studies indicated no diffraction peaks of Y2O3 were observed after 600℃ annealing.The Y2O3 thin films showed lowest leakage current density of~10-9 A/cm2 at an applied voltage of 2V.The capacitance density of Y2O3 dielectric is 526.8nF/cm2,and a relatively high dielectric constant of 14.9at 1kHz.Our results demonstrate that solution-processed Y2O3 thin film is a promising gate dielectric potential candidate for high-performance oxide TFT.
With respect to the fact that an electric vehicle lithium-ion battery′s uneven heat dissipation can affect the performance,reliability,and security of the battery,this paper made vehicle lithium-ion battery of a domestic company as the research object,cooling systemscentered around an air amplifier utilizing the Coanda effect of hydrodynamics.It used a small amount of highly pressurized air as a power source in order to form a high-speed,high-pressure flow of surrounding air that cools the battery effectively.It used fluent to simulate and the results showed that the maximum temperature within batteries using the air amplifier-based cooling system was 315 Kand the maximum temperature difference between individual batteries within each grouping was 6K.This shows that the cooling effect of the air amplifier-based system is good,and with the increase in the number of air amplifiers,and with an expansion to multiple air amplifiers,the cooling effect of this system can be further enhanced.Under similar conditions the maximum temperature within batteries of the fan-based cooling system is 317 Kand the maximum temperature difference between the batteries within each grouping is 7K.This system is easy to use and the cooling effect is good and has apromotion application value.
The alkali method was used to dissolve waste human hair for preparing keratin solution.Taking the dissolution rate of human hair and the mass fraction of keratin solution as test indexes,the optimum process conditions were determined by varying the dosage of sodium hydroxide amount,reaction temperature and time.The results showed that the dissolution rate was up to 90.42% and the mass fraction was5.66% when sodium hydroxide 0.4mol/L,reacting at 80 ℃for 3hours.SDS-PAGE analysis illustrated that the molecular weight of keratin was less than 15 kDa.From FITR and XRD analyses,the molecular structure of keratin was transformed fromα-helix toβ-sheet.The dissolution of human hair by alkali method caused the degradation of the polypeptide chains and the molecular weight of keratin was reduced.Furthermore,the secondary structures of keratin were also changed.Compared with the reduction method,the molecular weight of extracted keratin by alkali method is lower,but the dissolution rate of human hair and the mass fraction of keratin solution are higher.The study can meet the requirements of high efficiency and environmental protection.
