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1.
The interacting multiple model algorithm is used to solve the vehicle's tracking problems in automated highway system.It has multiple models,each of which matches to a particular mode such as uniform motion with constant velocity and maneuvering motion with acceleration.Combined with the target maneuvering models,the current acceleration of the target and its covariance are simulated.Significant noise reduction is achieved during the uniform motion.And it does better in maintaining the accuracy of the state estimates than the unfiltered radar measurements during the maneuver.A rapid detection of the maneuver is also obtained.The Monte Carlo simulation results show that the IMM algorithm will improve the target's tracking performance and enhance the vehicle's safety and reliability.  相似文献   

2.
An improved Mean shift based rocket target tracking algorithm is presented. The traditional Mean shift tracker is difficult in tracking fast moving rocket target and suffers in cumulating error. To overcome the limitation of the traditional Mean shift tracking algorithm, three frame difference method is employed to detect the rough position of rocket target. Based on the rough position, Mean shift algorithm is used to achieve precise tracking. Simulation experiments show that the proposed algorithm can effectively track fast moving rocket target and overcome the tracking error cumulating problems.  相似文献   

3.
After analyzing target recognition and tracking technique, a method of developing specifically target tacking system is proposed, which uses digital image manipulation to target recognition. Software and hardware design of intelligent vehicle are presented in detail. The system uses digital image manipulation technology to cognize the certain target through a pickup camera installed on the front of the intelligent vehicle. When the target is moving, singlechip receives the commands from the computer and then control the vehicle to trace target. The system can run by itself, regardless of artificial control. This design provides a platform for the research of Growing Machine Intelligence system.  相似文献   

4.
Intelligent buildings are more convenient and comfortable, however, their energy consumption during the operation arouses a big concern in society. In this article air - conditioning system operation control is studied mainly, meanwhile, to develop a kind of energy - saving air - conditioning system and put forward a strategy of energy conservation in air - conditioning, based on the calculation of the target on - line optimized function.  相似文献   

5.
Aim at the problem that the EO imaging tracking system is inconsistent with the model of probabilistic data association with amplitude information (PDA AI), which supposes that the greater the amplitude value is, the greater the probability of being the tracked target will be, a modified PDA AI (MPDA AI) is presented . Based on the fact that the amplitude and the motion of the interested target are consistent in a short period, the MPDA AI models the amplitude information and the motion information of the target as well as their consistency with Markov stationary signal to analyze the association procedure of motion and amplitude. The lower bounds of Cramer Rao estimation error for PDA AI and MPDA AI are calculated and discussed in detail. The theoretical analysis and experimental results show that estimating the target motion with the MPDA AI will be more accurate and more reliable than estimating with the original PDA AI.  相似文献   

6.
棉花产量目标和产量结构的动态知识模型   总被引:3,自引:3,他引:3  
通过分析和提炼棉花皮棉产量及产量结构的最新研究资料,在综合考虑气候条件、土壤肥力和栽培技术水平等影响因子的基础上,建立了棉花产量目标和产量结构的动态知识模型。该模型可用于精确定量不同气候条件、不同土壤肥力和不同栽培技术条件下的产量目标以及基于品种特性的产量结构。利用不同生态点资料对知识模型进行了验证,结果表明模型具有较好的决策性和适用性。  相似文献   

7.
Due to very large scale of general contract projects, the scope of projects is always uncertain when the contractor bids and the difference between the planned and actual volumes of projects is very large. If a lump sum contract is used to establish the price, contractors thus must take high risks. The contract price is always high, and both owners and contractors show unwillingness to optimize technology under lump sum contract conditions. Owners are inclined to extend the norm and scope of projects. Such situations may result in additional costs. As a new pricing contract, a target contract fits the situation when project scope is not fully defined or the forecasting risks are high. Such a contract can bring both sides enthusiasm for technology optimization and substantially reduces project cost. Therefore, a target contract is suitable for EPC general contract pricing.  相似文献   

8.
An algorithm of incremental model predictive control is proposed to solve a class of industrial production process real-time tracking problems. The basic idea is to establish a predictive model by adopting speed response on the basis of tracking error, and realize the optimization of the second time performance by using the soft constraint of the increment of control quantity and the online rolling optimization method. The theoretical analysis and Matlab simulation results show that the control algorithm can obtain good tracking performance, smooth dynamic response of the controlled object and strong robustness of the closed-loop system.  相似文献   

9.
In order to improve the long-playing frequency tracking ability in the signal processing for coriolis mass flowmeter (CMF) , a new IIR adaptive notch filter (ANF) is developed via steiglitz-mcBride method (SMM) and applied to filter the sensor output signal whose frequency, amplitude and phase are time-varying following the random walk model. The proposed method can detect the signal frequency fleetly and track the frequency variations continuously. The tracking performances of the proposed method and the adaptive lattice notch filter (LANF) method are investigated with computer simulations. Simulations demonstrate the superiority of the proposed method and show it has advantages of fast convergence rate, insensitivity to initial phase variations, and higher long-playing tracking stability and accuracy than LANF method.  相似文献   

10.
A fuzzy adaptive tracking control scheme is proposed for MIMO nonlinear time-varying delay systems. A fuzzy T-S model-based adaptive time-varying delay fuzzy logic systems is developed to approximate the unknown nonlinear time-varying delay functions.Thus, the modeling to nonlinear systems is implemented. The update laws for parameters of the fuzzy logic systems are derived by the tracking error. A Hcompensator is designed to eliminate fuzzy approximation errors and external disturbances. Based on Lyapunov stability theorem, the proposed control scheme can guarantee the stability of the closed loop systems and obtain anticipant Htracking performance as well. Simulation results of the manipulator demonstrate the effectiveness of the control scheme.  相似文献   

11.
We propose an estimation method for aircraft target direction based on histograms of oriented gradients (HOG), and then use the improved active shape model (ASM) to model the deformation between the different types of targets. Finally, we use kernel density estimation method (KDE) global statistical shape constraint to obtain the target to achieve the target recognition, and design a semi-automatic image feature point detection strategy for aircrafts, which improves the efficiency of training samples for calibration feature points. Recognition experiments on aircraft remote sensing images show the proposed method can better recognize aircraft targets than the existing methods.  相似文献   

12.
A mono-liquid model is established according to formative character of the premixed abrasive water jet. The hydraulic structure is analyzed by the model. The relationship that is obtained between the axial shaft line velocity and the forget distance by the law of conservation of momentum is verified with the experiment.  相似文献   

13.
This paper analyzes the principle of THS(Traditional Holo-Spectrum) technique,and in allusion to the deficiency of THS that only can be used in stationary signal,a new holo-spectrum technique based on order tracking is proposed.By order tracking sampling technology,non-stationary signal in the time domain is transformed into stationary signal in the angle domain,then the THS technique can be applied.Through this way,the influence of non-stationary to THS is reduced and the application of THS is extended.The paper researches the principle of order tracking holo-spectrum and verified by a simulation experiment.The simulation result and error analysis demonstrate that this method can be valid used to analyze the non-stationary signal.The spectrum is distinct and the effect is apparent.  相似文献   

14.
An improvement method is given to detect small weak targets. It predicts the background gray and the actual gray of the current pixel molded by two predicting windows. The method can not only solve the edge blur problem of the traditional method, but fit for the detection of the bipolar targets. It can perform at a high calculation speed, which is an important improvement in the filed. In the process of real-time missile-tracking. The reliability and stability of detection require that the method cannot only solve the edge blur problem of the traditional method, but work well with the background no matter it is bright or dark. According to the experiment using the images provided by DX-1 missile-tracking project, the method is proved effective.  相似文献   

15.
The mass flowrate of Coriolis mass flowmeter in practical application has slow changes with time. To solve the problem, an improved time-varying signal model whose frequency, amplitude and phase are time-varying based on the random walk model is established firstly. A new algorithm of adaptive notch filter with the capability of tracking frequency variation is applied to filter the sensor output signal of Coriolis mass flowmeter and its frequency is calculated next. An adaptive line enhancer based on the mentioned notch filter extracts fundamental frequency signal from noisy data. Then, by short window intercepting, the revised sliding DTFT recursive algorithm is introduced to calculate the real-time phase difference between two enhanced signals. With the frequency and phase difference obtained, the time interval between the two signals is calculated and then the mass flowrate is derived. The simulations and field test results show that the proposed method can not only track the change of frequency and phase, but also ensure the calculation accuracy when measuring small phase difference. The computational load of the algorithm is simple so that it can be applied to real-time signal processing for Coriolis mass flowmeter.  相似文献   

16.
Solar tracking has been described in several agronomic and wild species, yet variation within a given species has not been reported. To address that issue, photoperiod leaflet reorientation in response to vectorial light was measured in three alfalfa ( Medicago sativa L.) germplasm pools selected from the cultivar Ladak 65. Dark-leaf germplasm responded to all photosynthetic photon flux densities (PPFD) (100 to 700 μmol/m2/s) with no detectable lag period. Following a 24-h dark treatment only high PPFD (600 to 700μmol/m2/s) elicited reorientation. Pale-leaf germplasm responded to intermediate (300 to 400 μmol/m2/s) and high PPFD in a similar manner; however, the low (100-125μmol/m2/s) PPFD treatment had little effect on reorientation. The 24-h dark treatment decreased reorientation at all PPFD. Small-leaf germplasm responded equally to all PPFD and was not affected by the 24-h dark treatment. The results suggest that available energy levels may influence the reorientation response. Carbonyl cyanide m -chlorophenylhydrazone, an inhibitor of photophosphorylation, and 3-(3,4-dichlorophenyl)-1,1-dimethylurea, an inhibitor of non-cyclic photosynthetic electron transport, reduced reorientation only in the pale-leaf type. These results suggest that stored energy reserves were adequate to maintain leaflet reorientation in the absence of photosynthesis in all but the pale-leaf germplasm. In that germplasm photosynthetically generated energy may be required to support reorientation.  相似文献   

17.
玉米单交种冀单18号及其选育   总被引:1,自引:0,他引:1  
冀单18号是由“黄早_4×CB_5”组配的玉米单交种,丰产,适应性广,抗病性强,对肥水反应敏感,对光温气反应迟钝,稳产.在冀中南种植,生育期93天左右,麦田套种与夏播皆可.本项研究以亲本种质基础分析和生态型演变进化的有关理论作指导,探讨了现玉米生态阶段关键生态性状因素的选择指标.  相似文献   

18.
近几十年来,随着电子计算机技术的发展和应用,计算机自动控制被广泛地应用于国民生产生活的各个方面.虽然传统的方法可以绘制根轨迹,但各有其劣势.阐述了绘制根轨迹的基本思想、基本算法并给出了根轨迹仿真实例.对如何有效地进行根轨迹仿真做了进一步的探讨,就其中参数的设定做了进一步的分析和讨论.用计算机绘制根轨迹克服了传统方法的缺点,有效地提高了精度和速度.  相似文献   

19.
20.
棉花高产群体质量栽培技术   总被引:12,自引:2,他引:12  
根据多年的试验研究结果和大面积高产实践经验,总结出了反映棉花群体质量的六项指标以及高产群体质量栽培的配套技术措施,从而在高产理论和实践上丰富了棉花栽培学内容。  相似文献   

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