According to the characteristics of picking working in automated warehouse, a storage/retrieval scheduling optimization problem of a stacker crane is studied. The mathematic model of the order picking optimization is given based on two operation modes of a stacker crane, i.e. single access mode and combined access mode, and realized by means of the optimized Dijkstra algorithm, which makes it more intellectually to search path approaching to the target node and reduces traversing nodes. Experimental results show that this strategy can reduce the working distances of the stacker crane and promotes the efficiency of the automated warehouse.

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In the trust management scheme of the distributed cognitive radio networks, the absence of the central control devices cause many problems such as a lack of standardized control for trust computation, and the absence of the decision makers in trust evaluation and collaborative decision making. A trust management mechanism based on the jury system for distributed cognitive radio networks is proposed in this paper. The "jury user" is designed to collaboratively examine the reputation of the cognitive user in the networks and to perform data fusion and spectrum allocation for distributed cognitive radio networks. Simulation analysis results show that the proposed scheme can ensure accuracy and fairness in trust evaluation and improve effectiveness and flexibility of spectrum allocation.

With the reversible data hiding method based on pixel-value-ordering, data are embedded through the modification of the maximum and minimum values of a block. A significant relationship exists between the embedding performance and the block size. Traditional pixel-value-ordering methods utilize pixel blocks with a fixed size to embed data; the smaller the pixel blocks, greater is the embedding capacity. However, it tends to result in the deterioration of the quality of the marked image. Herein, a novel reversible data hiding method is proposed by incorporating a block merging strategy into Li et al.'s pixel-value-ordering method, which realizes the dynamic control of block size by considering the image texture. First, the cover image is divided into non-overlapping 2×2 pixel blocks. Subsequently, according to their complexity, similarity and thresholds, these blocks are employed for data embedding through the pixel-value-ordering method directly or after being emerged into 2×4, 4×2, or 4×4 sized blocks. Hence, smaller blocks can be used in the smooth region to create a high embedding capacity and larger blocks in the texture region to maintain a high peak signal-to-noise ratio. Experimental results prove that the proposed method is superior to the other three advanced methods. It achieves a high embedding capacity while maintaining low distortion and improves the embedding performance of the pixel-value-ordering algorithm.

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This work introduced the structural characteristic and working principle of cylinder offset oil-free lubricated wobble-reciprocating compressor. A mathematical model of crank-link mechanism was setup. The influence of cylinder offset to side clearance, side pressure and friction power were discussed. It revealed that when the offset applied on suction stroke side, the peak value of side pressure in suction stroke was relatively low in comparison to that of the compression stroke. Low friction loss was hereby achieved; meanwhile the system’s sealability was deteriorated, due to the larger backlash between piston and cylinder during the compression process. Reverse trend was found when the offset moved to compression stroke side. The side pressure in suction stroke and the friction power increased, with the decrease of side pressure of compression process and the improvement of sealability.

Because of automated guided vehicles (AGVs) routing flexibility, they have been used in many manufacturing systems, especially those in which parts with diverse and complex processing routes are made. This paper introduces the design of an material handling flow path control system in a partitioned zone through the timed Petri Nets. The initial requirements of a system specified with sequence diagrams are translated into a single timed Petri net model representing the route behavior of the system. Refer to the specifically part scheduling route for processing, setup a extended material flow matrix, then establish the corresponding timed Petri Net graphs to control a vehicle guide path tracks and location of the pickup (P) and dropoff (D) stations. The flowchart of control system design has its general-purpose modes considering all kind of circular routes with the dwell places, allowing easy adaptations to features corresponding to specific applications is highly desirable.

In this paper, we analyze the influencing factors of the customer loyalty and set up the relational assess model， then apply analytic hierarchy process to establish the relation weights which influence the customer loyalty. At last, by means of applied instances in telecommunication industry, we represent the internal relations between the influencing factor weights and the customer loyalty and put forward marketing strategies on product and customer divergences to develop the customer loyalty.