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As an economic and reliable transportation system, rounding autonomous guided vehicle is widely researched and implemented in logistics. However, higher automation implies less involving of manual control, which makes the unattended workshop prone to malicious attacks. Since the operation of rounding autonomous guided vehicle system largely depends on the accuracy of scheduling strategy, authenticity of rounding autonomous guided vehicle position must be preserved to avoid collision, priority breach, steal, etc. In order to ensure the correctness of positioning, a novel location acquisition and authentication scheme is proposed in this paper, with the help of message authentication code and verifiable threshold secret sharing. According to security and performance analysis, our scheme is resistant against chosen plaintext attack and feasible in rounding autonomous guided vehicle environment.

A novel method based on Hilbert Transform (HT) and Empirical Mode Decomposition (EMD) algorithm is proposed in this paper, which separates time series into intrinsic mode functions (IMFs) with different time scales and applies the Hilbert transformation for every IMF to obtain the Hilbert spectrum. Firstly, relevant theories of the proposed method are introduced. Then, based on these theoretical introductions, the fault vibration signals of rolling bearing are dealt with related algorithm. The research results demonstrate that the characteristic frequency of bearing fault can be obtained by proposed method, which is more effective compared with existing algorithm.

An accurate wind power forecasting model has great significance in wind farm operation and electric power system dispatching and operation. An auto regressive integrated moving average (ARIMA) time series model with Markov residual correction is proposed to forecast the wind power in this paper. After establishing ARIMA model, random residual sequence with Markov property can be proved through chi-square statistics. The residual correction model based on Markov chain is then established. The prediction results of wind power of two wind turbines and the wind farm are achieved. The results with the assessment of accuracy rate and qualification rate show that the proposed model has excellent performances and precision. Compared with time series and artificial neural network model, the accuracy is improved by 6–10%, and qualification rate is improved by 2–7%. The proposed method implements more simply than some combined models, which has better practical value.

The phenomenon of direct current (DC) magnetic bias is main cause of the increased noise and vibration of the transformer core and the magnetostriction is main cause of noise and vibration. This paper studies the magnetostriction characteristics of grain-oriented (GO) electrical silicon steel sheets. Especially the anisotropic magnetostriction along the rolling direction (RD) and transversal direction (TD) deviating from RD 90° was measured based on a standard single sheet measurement system, and the single-valued curves of magnetostriction were obtained to applied in the calculation of finite element (FEM). The vibration and noise of a 160KVA transformer caused by magnetostriction was calculated at no load under DC magnetic bias, are studied in detail.

A novel wastewater biological treatment process, internal-loop Anaerobic/Oxic/double Intermitted Aerobic Tank (A/O/IAT-IAT), was investigated for simultaneous removal of nitrogen and phosphorus. Satisfactory nitrogen and phosphorus removal performance was achieved in both lab scale reactor and pilot plant. Over 90% removal efficiencies were accomplished in the experiments with average effluent concentration of NH 4 +-N and PO 4 3−-P being 2.5 mg/L and 0.1 mg/L receptively.

Smart grid is a hot topic about the future development trend of power grid in recent years, as an important component of smart grid, smart automatic voltage control (AVC) has been given more and more attention. This paper starts with the construction ideas of smart grid, put forward the concept of Smart AVC, and by comparing the Smart AVC system and traditional AVC system, from the building background, technical features, construction process and benefit analysis etc sides described the design concept of Smart AVC.

This paper presents that when power/voltage automatic control system (AVC) is being applied in provincial dispatching centre, in order to implement reactive power/voltage optimization control on condition of ensuring limited on-line voltage stability margin, monitoring module of on-line voltage stability should be introduced to realize the coordinated closed loop control of on-line voltage stability monitoring and AVC system. It defines the concepts of voltage lower limit of on-line voltage stability constraint and dynamic reactive power reserves of generator and considered them for AVC system as constraints to enhance the reliability and security of AVC system. The successful application in Fujian power grid indicate that the proposed method can reduce system active power loss based on ensuring limited on-line voltage stability margin.

Combining with the characteristic of medium voltage power distribution grid, this paper puts forward a simplifying partition algorithm of reliability evaluation to medium voltage power distribution network. At first, the system is simplified; branch sub-feeder is made to be equivalent to an element, so the system is simplified. Then the construction method of adjacency matrix is presented. Finally, the partition algorithm of power distribution network is come into being. Considering that the common tree operating of medium voltage distribution network, so the adjacency matrix is stored by making use of sparse technique. During the fault is analyzed and simulated, the fault enumeration time and repeated searching time of switching element is saved greatly. Reliability evaluation has been taken on the bus of the testing system RBTS-4 presented in the literature by applying the algorithm, and the calculating example has shown that the algorithm has high efficiency and engineering practicability.

The problem of energy-to-peak control for a class of continuous time-varying delay systems with Markovian switching parameters is discussed. In this paper, such control problem requires that the resulted closed-loop system is exponentially stable in mean square sense with given L2-Hinfindisturbance attenuation. The Markovian switching considered here forms a continuous-time discrete-time homogeneous Markov process. In terms of stochastic Lyapunov function method and linear matrix inequality, sufficient criterion for such control problem is proposed. Additionally this note also corrects some previous results. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

The exponential stability of nonlinear Ito differential systems with time-delay and Markovian switching is studied. According to the theory of stability of stochastic systems and Ito differential formula, by choosing proper stochastic Lyapunov function, applying generalized Ito formula, some sufficient conditions of exponential stability of such system was obtained, which improved existed results, with less conversations.

There are some problems in comprehensive evaluation of maintenance quality. For example, the evaluation is invisible, the importance of each factor is unclear, and especially the appraisal results ordering of several appraisal objects with similar maintenance quality performance is difficult. For this, this paper presents an improved radar chart model and studies the fuzzy comprehensive evaluation of maintenance quality based on this model. At first, the maintenance quality index system is set up. Then the preliminary evaluation on the first layer index is made using the multi-attribute fuzzy comprehensive evaluation method, and the index weight is calculated according to AHP. Finally, the improved radar chart model of maintenance quality is constructed for comprehensive evaluation. With analysis of a case study, the result shows the validity of the model in maintenance quality evaluation.

Sparse-array synthetic impulse and aperture radar (SIAR) adopts the isotropic radiation scheme, thus can perform the long-time coherent integration. However, there are some problems in the process. In this paper, an effective method for long-time coherent integration is presented, which includes a simply implemented motion compensation and time-frequency analysis. The result shows that the novel method has good performance for weak target detection.