Blackbody radiation source is used as a standard device for infrared thermometer, it plays increasingly important roles in the field of calibration. Through experiment discoveries that it is a typical nonlinear system...
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Blackbody radiation source is used as a standard device for infrared thermometer, it plays increasingly important roles in the field of calibration. Through experiment discoveries that it is a typical nonlinear system and has a large transport delay when the blackbody is rise temperature or cooling in order to reach set temperature points. Based on the temperature control of blackbody is a kind of typical multi-variable, strong coupling and time-varying nonlinear controlsystem. The paper proposes applying the theory of active disturbance rejection controller (ADRC) to suppress various disturbances and improve the dynamic performance of blackbody radiation source. First of all, describing the working principle of blackbody radiation source and building its mathematical model. Secondly, introducing the control method of ADRC, which is applied to the temperature controlsystem of blackbody radiation source. Finally, through MATLAB/SIMULINK platform to simulate and compare the temperature control performances of blackbody among ADRC, PID and Smith predictor(SP) control strategies. The simulation results show that proposed ADRC algorithm improves the abilities of anti-interference of system and it is without overshoot. In addition, the results also indicated that the control method of ADRC shortens plant stable time and has a strong prospect for practical applications.
With the extensive use of distributed generation, the traditional demand response analysis cannot meet the current *** paper proposes a NSGA-II based peak load shifting optimization method for customers with distribut...
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With the extensive use of distributed generation, the traditional demand response analysis cannot meet the current *** paper proposes a NSGA-II based peak load shifting optimization method for customers with distributed generators considering time-of-use price. Firstly, a fuzzy classification method divides the daily power into three time segments,peak hours, flat hours and valley hours. Secondly, on the basis of the time-of-use price, a peak load shifting optimization model is built with constraints and the objectives of minimizing the peak load, maximizing the valley load, and minimizing the peakvalley difference. Then, a NSGA-II based optimization method solves the optimal model and obtains the optimal electricity prices of different time segments to shift the peak load and the valley load. Finally, the simulation results shows the effectiveness of the proposed method.
In the process of image acquisition, non-uniform illumination images are common due to poor lighting, surface reflection, or a combination of these two factors. In order to improve the quality of image segmentation, a...
In the process of image acquisition, non-uniform illumination images are common due to poor lighting, surface reflection, or a combination of these two factors. In order to improve the quality of image segmentation, an image threshold segmentation method is proposed for non-uniform illumination images. First, the brightness of different regions in the image is compensated to make the brightness background of the whole image consistent. Second, the gradation histogram of the processed image is obtained and simulated into Gaussian distribution curve, then the inflection points of the curve are calculated. Finally, the two inflection points are set as thresholds to segment the image after brightness equalization. This method eliminates the influence of non-uniform illumination to a certain extent and gets a better segmentation effect. Experiments were carried out on images containing several different types of non-uniform illumination. The results demonstrate that the proposed method outperforms the compared enhancement algorithms in threshold segmentation.
Image retrieval is a hot research topic in the field of computer vision image processing, and the user queries the image database for similar images and produces a list of recommendations. The paper firstly sets forth...
Image retrieval is a hot research topic in the field of computer vision image processing, and the user queries the image database for similar images and produces a list of recommendations. The paper firstly sets forth the research status of image retrieval, then the convolution neural network is briefly introduced. Due to the traditional image retrieval and recommendation system use manual extraction of image features is relatively cumbersome, and the retrieval accuracy is not high research status, the paper proposes an image retrieval method based on the improved convolutional neural network and linear discriminate analysis. Caltech256 and CIFAR-10 datasets were trained using the model in this paper, experimental, results show that the proposed method can effectively improve the performance of retrieval.
Disturbance rejection performance for rolling hydraulic position controlsystem has always been a knotty issue. To guarantee the transient performance and improve disturbance rejection performance of the rolling hydra...
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Cells in organisms are surrounded by fluid environment, and the fluid shear force produced by this fluid affects the morphology and behaviour of cells. The stimulation of cells in a bioreactor is a key area of researc...
Cells in organisms are surrounded by fluid environment, and the fluid shear force produced by this fluid affects the morphology and behaviour of cells. The stimulation of cells in a bioreactor is a key area of research in tissue engineering and regenerative medicine. This paper introduces a fluid shear system for cell culture in vitro. The main component of system is a perfusion chamber, which consists of an inoculation room and a perfusion cap. The inoculation room is used for the common laboratory consumables of microorganism or cell culture, such as petri dish, six-well plate and so on. It can realize to six independent experiments of fluid shear; the new type of perfusion cap was designed to obtain a reasonable cavity by hydrodynamic simulation. The cap was produced by casting technology. It not only has the function of cap with nozzles, but also has the function of sealing. With peristaltic pumps, nozzles, liquid storage bottles and so on, the fluid shearing system which can provide uniform, controllable and up to 60 dyn/cm2 shear stress along the bottom surface is constructed, and is easy to operate and can be personalized.
The load sensing steering system of wheel loaders,driven by a constant displacement hydraulic pump,commonly leads to the large overflow and throttling loss during steering *** order to improve
The load sensing steering system of wheel loaders,driven by a constant displacement hydraulic pump,commonly leads to the large overflow and throttling loss during steering *** order to improve
The zero-magnetic-field oscillation behavior of spin torque nano-oscillator (STNO) with a perpendicularly mag- netized free layer with second-order uniaxial anisotropy is studied theoretically based on the Landau-Li...
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The zero-magnetic-field oscillation behavior of spin torque nano-oscillator (STNO) with a perpendicularly mag- netized free layer with second-order uniaxial anisotropy is studied theoretically based on the Landau-Lifshitz- Cilbert-Slonczewski equation. It is demonstrated numerically that the second-order uniaxial anisotropy plays a significant role in the occurrence of a zero-magnetic-field steady-state precession, which can be understood in terms of the energy balance between the energy accumulation due to the spin torque and the energy dissipation due to the Gilbert damping. In particular, a relatively large zero-magnetic-field-oscillation current region, in which the corresponding microwave frequency is increased while the threshold current still maintains an almost constant value, can be obtained by modulating the second-order uniaxial anisotropy of the free layer. These results suggest a tunable zero-magnetic-field STNO, and it may be a promising configuration for STNO's applications in future wireless communications.
Organic-inorganic hybridized perovskites have attracted more and more attention due to their advantages such as high absorption coefficients, direct band-gap, long carrier lifetimes, balanced electron/hole mobility, *...
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Organic-inorganic hybridized perovskites have attracted more and more attention due to their advantages such as high absorption coefficients, direct band-gap, long carrier lifetimes, balanced electron/hole mobility, ***-scaled perovskites, which possess naturally-formed optical feedback, can excite resonance under certain incident light and realize the precise light management as *** 2014, Ha et *** lead halide perovskite nanoplatelets with regular triangular or hexagonal morphologies by vapor phase deposition techniques on mica plate [1].Later, they realized lasing based on the whispering-gallery modes at the near-infrared range using the prepared perovskite nanoplatelets [2].Here, we first synthesized lead iodide nanoplatelets with well-defined crystal boundaries and then successfully conversed the pre-grown lead iodide template into perovskite nanoplatelets by placing the substrate exactly above the methyl iodide amine powder in Ar gas condition with all valves of the quartz tube *** a continuous-wave laser at 325 nm, we measured the photoluminescence spectra of different perovskite nanoplatelets and observed the whispering gallery modes over the spontaneous emission band.
This paper investigates the problem of Synchronous control of Fractional gene regulatory *** on the Lyapunov stability judgment method,we apply two kinds of control method,adaptive projection control and adaptive slid...
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ISBN:
(纸本)9781538629185
This paper investigates the problem of Synchronous control of Fractional gene regulatory *** on the Lyapunov stability judgment method,we apply two kinds of control method,adaptive projection control and adaptive sliding mode control,for making system ***,a numerical simulation example is provided to verify the effectiveness and the benefit of the proposed synchronicity criterion.
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