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991.
The solubility and processability of polyaniline can be increased through aniline copoly with o-anisidine. Poly(aniline-co-o-anisidine) have good electrochromism .On condition that mole ratio between aniline and anisidine is 3:1,better reaction conditions of synthesizing poly(aniline-co-o-anisidine) with good solubility ,electrochromism and high yield was gotten through researches for effects of monomer ratio,monomer concentration,the amount of oxidant ,reaction times,reaction temperature,acid concentration on properties of poly(aniline-co-o-anisidine).The structure of polymers were characterized by IR spectrum.  相似文献   
992.
993.
汽车是人机协同控制的复杂系统,基于NI PXIe8108实时控制器、PXI7842R数据采集卡、模拟驾驶输入设备及相关软硬件搭建了驾驶模拟仿真系统;用LabVIEW编程语言建立了车辆动力学模型;用虚拟引擎Unity3D软件开发了视景系统;并通过数据库技术使仿真过程与视景系统相结合,实现仿真过程与三维动画实时视景系统的数据交互。结果表明:通过人在环路模拟驾驶仿真实验,使仿真过程中引入了驾驶模拟操纵,实现了人在环路的人机交互式仿真,得到汽车相关性能仿真结果,为驾驶过程中人和汽车协同控制仿真和极端工况下的仿真,提供了一种安全、可靠的人车协同控制仿真环境。  相似文献   
994.
Compared with the traditional full-bridge(FB)zero-voltage-switched(ZVS) pulsewidth-modulated(PWM) converter, the FB-ZVS-PWM converter with a saturable inductor has a wider load range with ZVS and smaller circulating energy as well as smaller duty cycle loss. By analyzing the operation principle of the converter, this paper studies design considerations of the parameter bringing about ZVS and dead time of the switch, and gives out the design method, finally simulation testing has been carried out.  相似文献   
995.
This article presents an implement of component using COM technology for collecting environmental monitoring data in environment monitoring system. The component makes the separation of data collection and data analysis available.Simultaneously by using the interface of connectable object in COM,itmakes the cooperation of the environment monitoring software with other parts of fault management software available,and also the seamless connection.It improves the system's performance by adding extensibility and potential cooperatibility.  相似文献   
996.
997.
A novel edge detection algorithm is proposed by implementing fuzzy image enhancement at different scales.The implement of this algorithm can reduce the negative influence bring from the non-maximum suppression algorithm which select only one threshold.The success of the approach depends on the selection of a general fuzzy operator(GFO) for the enhancement of contrast of region after smoothing of image at different scales.Consequently,it is more obvious that coarse intensity changes are obtained at a large scale whereas the fine details of intensity changes are obtained at a small scale.A pretty performance is obtained by used this work.  相似文献   
998.
In this paper, the machine( physical) parameters of the alternator system are on-line estimated on the basis of the derived system continuous-tims model, using Recursive Least-squares Estimation and Inverse Calculation Method proposed by Authors. Therefore, the estimated machine parameters can effectively track the changes of their true values and accomplish the fault detection for the alternator system. This paper gives a new way for machne parameter estimation and fault detection of the alternator systems.  相似文献   
999.
《保鲜与加工》1997,(6):7-14
This paper discusses practical methods of investment risk analysis at a construction project,applying the Xifang Economics Principle and the Mathematical statistics etc, It has reference value for improving the Feasibility Research(FR)and Investment Decisions.  相似文献   
1000.
In general, the process of synthesis the refractory nanoparticles Is classified as solid state, liquid state and gaseity. The new progress and development in the study of refractory nanoparticles are investigated. The synthesis technology of the refrectory nanoparticle in liquid state is discussed mostly. The refrectory nanoparticles is synthesized by the liquid state. The characteristics and the structure of the refrectory nanoparticles have been studied in this paper.  相似文献   
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