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Human perception of an object is modeled in
and simulated in
. A colorimetric package incorporating CIE color representation standards is defined in
. The colorimetric system under foggy, thermal, and electrical conditions is considered and analyzed as a multi-technological system when the light source is perceived to the eyes of people. Our
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translator compiles models which reference the package. The results of this work can be useful for the pilots of an aircraft guided by runway display systems after landing or before taking-off under severe conditions. 相似文献
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《Solid-State Circuits, IEEE Journal of》1986,21(4):555-560
A theoretical explanation for fixed pattern noise (FPN) is given for the MOS-CCD image sensor with the use of external bias charge. The FPN is ascribed to the fluctuation of the bias charge which is returned from the coupler between the vertical transport line and the horizontal CCD (H-CCD) shift register. It is shown that the FPN is eliminated below -60 dB with respect to the maximum output signal in the case of vertical transfer efficiency of 97% or more. 相似文献
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运营支撑系统是IPTV平台的一个重要组成部分,对它的建设必须坚持高起点、严要求.运营支撑系统应该具备:先进性、实时性、安全性、可用性、可靠性、可维护性、可操作性、开放性和可扩充性.IPTV运行支撑系统功能结构如图1所示. 相似文献
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A vision-based system is described for adaptive cruise control to track road signs from within a moving vehicle. The proposed system has the standard architecture with a particle filter due to its robust tracking performance in a complex environment. In the case of tracking road signs in a real environment, it has great difficulty in predicting time series data by reason of its nonlinear characteristics. To overcome this problem, proposed is a state transition model to which the differences of affine parameters and a fuzzy-autoregressive model are applied. Also, to make an observation model, the Parzen window is used at a measurement step in the particle filter. 相似文献
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Scheme EJ Englehart KB Hudgins BS 《IEEE transactions on bio-medical engineering》2011,58(6):1698-1705
Recent literature in pattern recognition-based myoelectric control has highlighted a disparity between classification accuracy and the usability of upper limb prostheses. This paper suggests that the conventionally defined classification accuracy may be idealistic and may not reflect true clinical performance. Herein, a novel myoelectric control system based on a selective multiclass one-versus-one classification scheme, capable of rejecting unknown data patterns, is introduced. This scheme is shown to outperform nine other popular classifiers when compared using conventional classification accuracy as well as a form of leave-one-out analysis that may be more representative of real prosthetic use. Additionally, the classification scheme allows for real-time, independent adjustment of individual class-pair boundaries making it flexible and intuitive for clinical use. 相似文献
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借用宏观领域中双线性系统的研究成果,结合量子系统数学模型所具有的双线性系统形式的特点,通过对含有两点边值条件的最优控制器的推导,对量子力学系统进行最优迭代控制器的设计,并通过仿真实验对设计的量子控制系统的状态转移控制进行系统仿真实验,分别对控制参数的不同取值对控制结果的影响进行了详细的分析. 相似文献
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A. A. Strotsev I. V. Shcherban’ S. A. Funtikov V. A. Bertenev 《Radioelectronics and Communications Systems》2007,50(9):491-496
Mathematical model of the aircraft optimal control ensuring the probability maximization of its undetection by a group of measuring and search points forming part of a multiposition complex information-search system was obtained. To solve the problem, a model of search efforts specification was used where the control of each measuring and search terminal was assumed to be known. 相似文献
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Hong-Seok Song Kwanghee Nam 《Industrial Electronics, IEEE Transactions on》1999,46(5):953-959
Voltage unbalance in a three-phase system causes performance deterioration of PWM power converters by producing 120 Hz voltage ripples in the DC link and by increasing the reactive power. To eliminate the DC link voltage ripple and the DC component of the reactive power, both positive- and negative-sequence currents should be controlled simultaneously, according to the paper by Rioual et al (1996). The authors used two synchronous reference frames: a positive-sequence current regulated by a proportional integral (PI) controller in a positive synchronous reference frame (SRF); and a negative-sequence current regulated by a PI controller in a negative SRF. In the positive SRF, which rotates counterclockwise, the positive sequence appears as DC, while the negative sequence appears as 120 Hz. In contrast, in the negative SRF, which rotates clockwise, the negative sequence appears as DC, while the positive sequence appears as 120 Hz. By deleting 120 Hz components using a notch filter in each SRF, one can measure positive- and negative-sequence currents separately, and use them for constructing two feedback controllers. Since the negative-sequence current is also controlled in its own SRF by a DC command, this approach yields better performance without increasing the control gain. Note that, since the controller is implemented by a software routine in the digital signal professor chip, using two SRFs does not require additional hardware. The authors demonstrated the effectiveness of the proposed control scheme by using computer simulation and experiments 相似文献
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This paper deals with the stochastics behaviour of a man-machine system which is affected by the operator physical conditions. Operator physical condition is subject to a Markov process with two states - good and poor and is independent of the system state. Operating unit fails either due to operator error or system fault. Using Markov reneval process several characteristics such as mean time to system failure (MTSF), pointwise availability in (0,t], expected busy period of the repairman in (0,t] and expected profit earned by the system in (0,t] have been obtained. 相似文献
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Ghijselen J.A.L. Van den Bossche A.P.M. Melkebeek J.A.A. 《Power Electronics, IEEE Transactions on》2001,16(1):118-124
A three-phase, sinusoidal, active rectifier is presented, based on the classical inverter topology. The switches are governed by a fixed pulse width modulation (PWM) pattern, and the control strategy is extremely simplified as compared with many active rectifiers. General equations describing the steady-state operation of fixed pattern rectifiers are given. A dynamic model of the simplified control rectifier is presented, based on the nonlinear equations describing the system. Based on the analytical model, the classical PI-controller yields poor dynamic results, especially at low load conditions. However, the dynamic performance of the prototype is much better, due to the effects of commutation dead time of the rectifier switches. It is shown that a small modification to the classical PI-controller yields a remarkable increase in amplitude and phase margin, without slowing down the response. The obtained dynamics show a clear improvement over the classical PI-controller and are adequate for most applications 相似文献
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电信运营商业务支撑系统投资巨大,在项目可行性研究阶段使用合理方法精确估算投资显得非常重要.本文分析了现有投资估算存在的问题,通过对历史数据进行统计分析,提出了优化思路. 相似文献
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本文在两种接地条件(即共地情况和隔离地情况)下分别设计制作了两个片上变压器,并对这两个片上变压器的不同特性进行了相应的测试与比较。借助于电磁场仿真软件,本文分别从电场和磁场两方面对两种接地条件下片上变压器的不同性能进行深入分析。从等效电路模型的角度考虑,片上变压器在这两方面(即电场和磁场方面)的差异可以归结为集总电容和集总电感的差异。基于物理意义,本文为两种接地条件下的片上变压器提供了等效电路模型。另外,针对相应等效电路模型的简单参数提取方法同样呈现在文中。本文对模型中的所有参数均进行提取,提取结果与前文的分析相吻合。为了检验所提出模型的有效性和准确性,本文比较了模型仿真和实际测试下的散射参数,发现两者在很宽的频率范围内均吻合得很好。 相似文献
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为了减小激光雷达散射截面(LRCS)测量过程中激光能量和大气状态不稳定带来的测量误差,提高LRCS测量准确度,采用基于多个探测单元同时测量的多站对比误差校正方法,推导了一个新的LRCS计算公式,讨论了传统对比方法测量LRCS的适用范围和局限性,分析了在非理想条件下激光器的能量起伏和大气状态的变化对LRCS计算带来的误差,并通过实验对两种方法的测量结果进行了分析比对。结果表明,设计的多站比对测量方法科学可行,采用多站对比公式计算的LRCS值准确度高,可以有效减小或消除测量过程中激光能量和大气状态的不稳定带来的测量误差。 相似文献