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According to the unsafety exist in the steel cord conveyor belt running, introduces the design of a new steel cord conveyor belt online testing system which based on ARM and sensors array, describes the system hardware, software, and testing results in detail.

The stability control problem is considered for a class of discrete-time T-S fuzzy bilinear system with time-varying delay in both state and input. Based on the parallel distribute compensation (PDC) scheme, some sufficient conditions are derived to guarantee the global asymptotically stability of the overall fuzzy system, which are represented in terms of matrix inequality. The corresponding controller can be obtained by solving a set of linear matrix inequalities. Finally, a simulation example shows that the approach is effective.

In this paper, an open-loop frequency domain analysis based on system identification is introduced. Using model identification tools in Matlab, the open-loop frequency domain characteristic could be derived accurately with the open-loop step response. Then, the closed-loop regulator could be designed with the open-loop frequency domain characteristic to fulfill the steady and dynamic requirements. This method is suitable for most of the systems. An example of Buck converter is proposed to represent the analysis process. Simulation model is built in Matlab software, and some factors which affect the precision of model identification and frequency domain analysis are taken into consideration. Finally, both open- and closed-loop experimental results verify the feasibility of the proposed scheme.

Testis development and ultrastructural features of spermatogenesis in Acrossocheilus fasciatus (Cypriniformes, Barbinae), a commercial stream fish, were studied using light and electron microscopy. The reproduction cycle in A. fasciatus testes is classified into six successive stages from Stage I to Stage VI. Based on an analysis of previous results, May to July can be confirmed as the best breeding season for A. fasciatus males. During this time, the A. fasciatus testes are in Stage V and the sperm in males is most abundant. In the first reproductive cycle, sexually mature male testes return to Stage III in October, subsequently overwintering at this stage. In the lobular-type testes of A. fasciatus, cystic type spermatogenesis occurs with restricted spermatogonia. All spermatogenic cells at different stages are distributed along the seminiferous lobules, which contain spermatogonia, spermatocytes, spermatids and spermatozoa. At the end of spermatogenesis, spermatogenic cysts open to release spermatozoa into the lobule lumen. Ultrastructural observation of A. fasciatus spermiogenesis reveals that electron-dense substances appear at the different stages of germ cells, from primary spermatogonia to secondary spermatocytes. We have termed these dense substances as "nuage" when free in the cytoplasm or adjacent to the nuclear envelope, while those close to the mitochondria are called inter-mitochondrial cement. The spermatozoa in A. fasciatus can be classified as type I due to the presence of nuclear rotation. Although the nuclear chromatin in the head of sperm was highly condensed, no acrosome was formed. The cytoplasmic canal, a common ultrastructural feature of Teleostei spermatozoa, was also present in the midpiece. In addition, numerous fused mitochondria were observed. The distal centriole and proximal centriole constituting the centriolar complex were oriented incompletely perpendicular to each other. The flagellum showed a typical 9+2 arrangement pattern. Conversely, our study on A. fasciatus yielded no information concerning the lateral fins although an enlarged saclike area was present at the end of some flagella.