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81.
To form a high-performance video quality predictor, we developed a framework for full-reference (FR) video quality assessment that integrates Spatio-temporal slice analysis (STS) to create a high-performance predictor of video quality. However, both gradient and Gabor are spatial–temporal structural capturers used for the simultaneous extraction of both spatial and temporal features. In this paper, we proposed a novel VQA algorithm via a joint model of gradient magnitude and Gabor features (JMG) between the STS images of the reference videos and their distorted counterparts to assess the degradation of video quality effectively. Firstly, gradient magnitude and the Gabor filter were constructed to extract the spatiotemporal features of the video sequence. However, the two-feature model combined to predict the perceptual quality of frames. This new proposed VQA model is known as the horizontal and time STS (HT-JMG) model. To further investigate the influence of spatial dissimilarity, we combined the frame-by-frame spatial T-JMG(S) factor with the HT-JMG and propose another VQA model, called the time, horizontal, and vertical STS (THV-JMG) model. Finally, the results of the experiment showed that the proposed method has a strong correlation with subjective perception and is competitive with state-of-the-art full reference VQA models. 相似文献
82.
The aim of this study is to reduce the phosphate concentration in treated wastewater using a small amount of the reactive filter media, Filtralite P. Biologically treated wastewater was passed through a filter with 215 g of Filtralite P. In the laboratory, the phosphate removal efficiency was 51% at a flow speed of 0.87 m/h. Under real conditions, in an experimental stand filled with 0.5 m3 of Filtralite P, the phosphate removal efficiency was 85% and the removal efficiency of total suspended solids was 57% after a 5‐month period. The residual phosphate concentration in the filtrate from the experimental stand was 1 mg/L of PO4‐P after the 5‐month period. The experimental filtration plant was buried in the ground, and it did not freeze and worked well under winter conditions. The results of this study can be useful in the design and development of tertiary wastewater treatment plants in view of their sustainability potential. 相似文献
83.
Hicham El Aiss Taha Zoulagh Ahmed El Hajjaji Abdelaziz Hmamed 《International Journal of Adaptive Control and Signal Processing》2021,35(5):748-768
This article addresses the issue of delay-dependent H∞ filtering design for TakagiŮSugeno fuzzy time-varying delay systems using the input–output approach. A three-term approximation model has been used to transform the original system into two interconnected subsystems. Since the nonquadratic Lyapunov–Krasovskii functional requires to deal with the membership function's (MF) time derivative, upper-bound inequalities have been added to the obtained conditions. Based on the scaled small gain theorem, nonquadratic Lyapunov–Krasovskii functional approach and considering the bounds of the MF time-derivative, the H∞ full- and reduced-order filters are designed and then formulated in terms of linear matrix inequalities. Finally, illustrative examples are presented to demonstrate the validity of the proposed methods. 相似文献
84.
《全球能源互联网(英文)》2021,4(2):184-192
This paper presents an effective and feasible method for detecting dynamic load-altering attacks (D-LAAs) in a smart grid. First, a smart grid discrete system model is established in view of D-LAAs. Second, an adaptive fading Kalman filter (AFKF) is designed for estimating the state of the smart grid. The AFKF can completely filter out the Gaussian noise of the power system, and obtain a more accurate state change curve (including consideration of the attack). A Euclidean distance ratio detection algorithm based on the AFKF is proposed for detecting D-LAAs. Amplifying imperceptible D-LAAs through the new Euclidean distance ratio improves the D-LAA detection sensitivity, especially for very weak D-LAA attacks. Finally, the feasibility and effectiveness of the Euclidean distance ratio detection algorithm are verified based on simulations. 相似文献
85.
Fuyi Qu Shaocheng Tong 《International Journal of Adaptive Control and Signal Processing》2019,33(4):567-585
This paper focuses on consensus quantized control design problem for uncertain nonlinear multiagent systems with unmeasured states. Every follower can be denoted through a system with unmeasurable states, hysteretic quantized input, and unknown nonlinearities. Fuzzy state observer and Fuzzy logic systems are employed to estimate unmeasured states and approximate unknown nonlinear functions, respectively. The hysteretic quantized input can be split into two bounded nonlinear functions to avoid chattering problem. By combining adaptive backstepping and first‐order filter signals, an observer‐based fuzzy adaptive quantized control scheme is designed for each follower. All signals exist in closed‐loop systems are semiglobally uniformly ultimately bounded, and all followers can accomplish a desired consensus results. Finally, a numerical example is employed to elaborate the effectiveness of proposed control strategy. 相似文献
86.
Muhammad Shamrooz Aslam 《International Journal of Adaptive Control and Signal Processing》2021,35(7):1336-1353
This article concerns the event-triggered fuzzy filter design for Takagi-Sugeno (T-S) fuzzy systems subject to deception attacks under the stochastic multiple time-varying delays. A sequence of random variables, which are mutually independent but obey the Bernoulli distribution, is introduced to account for the randomly occurring communication delays. In order to efficiently utilize limited network communication bandwidth resources, the event-triggering scheme is adopted. A fuzzy filter with the attacked input signal is presented. Moreover, due to communication delays caused by event-triggering schemes and transmission, the filter adopts non-synchronous premise variables with the system. Then, by utilizing a model transformation technique, the fuzzy systems are developed. Furthermore, using the piecewise Lyapunov functional method technique, the resulting criterion provides sufficient conditions to ensure that fuzzy systems under deception attacks are stochastically stable with an H∞ performance. Accordingly, the conditions for the co-design of the fuzzy filter and event-triggering schemes are given. Finally, numerical simulation with the industrial process provided to verify the proposed event-triggered design. 相似文献
87.
地磁图是影响地磁匹配导航性能的重要因素,其中地磁图的随机误差严重影响匹配定位精度,甚至导致误匹配。 为提
高地磁匹配性能,提出了地磁图数据随机误差建模与补偿方法。 该方法在对地磁图数据随机误差特性分析的基础上,建立数据
的非平稳时间序列模型,并将此模型作为状态方程,以实时数据为量测量,采用 Kalman 滤波方法对地磁图数据进行滤波,补偿
地磁图数据的随机误差。 通过基于滤波前后地磁图数据的导航定位实验,间接证明滤波方法的有效性。 对实际地磁图数据处
理结果表明,应用该方法滤波后的地磁图数据进行导航,其定位精度提高了 54. 7%。 相似文献
88.
对工程中求取可靠的插值节点提出一种基于数理统计的方法。对足够的稳态数据进行卡尔曼滤波处理,把经过滤波后的稳态数据进行概率分布分析后,通过拟合优度检验判定测量数据的分布类型并求出合理值(数学期望)作为插值节点。以此方法处理检测区间内的采样点,得出传感器特性曲线。对某种CO2数字传感器进行实验验证,通过与传统的求均值方法进行比较,结果表明:该方法能够更加精确地估计出真实值,比普通均值拟合精度提高13%。 相似文献
89.
采用热压技术将熔体静电纺纤维与传统非织造织物在线复合,制备熔体静电纺热压复合过滤材料,探讨热压压力、热压温度和收集速度对复合过滤材料过滤性能、剥离强力与断裂强力的影响。结果表明,熔体静电纺纤维经热压后良好贴附在非织造基材表层;随着热压压力的增加,复合过滤材料的过滤性能得到一定提高,剥离强力随之增大,断裂强力先增大后急剧减小;热压温度对复合过滤材料的过滤性能影响不大,但对其力学性能有较大影响,复合过滤材料的剥离强力和断裂强力随着热压温度的增加而增大;随着收集速度的减小,复合过滤材料的过滤效率、剥离强力和断裂强力均有所提高。 相似文献
90.