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In order to overcome the premature convergence defect of the basic particle swarm optimization (PSO) algorithm and provide an effective method for shape and sizing optimization of truss structure, an improved PSO was proposed. The random direction method was employed to produce high-quality initial population, the fuzzy system was applied in the dynamic adaptive adjustment of parameters of the PSO, and the Metropolis criteria were used to improve the performance of PSO. Then, the improved PSO was introduced to the truss structure shape and sizing optimization design. Engineering practice and comparison with the other optimization algorithms show that the algorithm has good convergence and global searching capability. The study provides a promising algorithm for the structural optimization.

OBJECTIVE: To evaluate whether teicoplanin could be an alternative to vancomycin for treatment of MRSA infection in Chinese population using a meta-analysis in randomized controlled trials. METHODS: THE FOLLOWING DATABASES WERE SEARCHED: Chinese Biomedical Literature database (CBM), Chinese Journal Full-text database (CNKI), Wanfang database, Medline database, Ovid database and Cochrane Library. Articles published from 2002 to 2013 that studied teicoplanin in comparison to vancomycin in the treatment of MRSA infected patients were collected. Overall effects, publishing bias analysis and sensitivity analysis on clinical cure rate, microbiologic eradication rate and adverse events rate were performed by using Review Manager 5.2 and Stata 11.0 softwares. RESULTS: Twelve articles met entry criteria. There was no statistically significant difference between the two groups regarding the clinical cure rate (risk ratio [RR], teicoplanin vs vancomycin, 0.94; 95% CI, 0.74~1.19; P=0.60), microbiological cure rate (risk ratio [RR], teicoplanin vs vancomycin, 0.99; 95% CI, 0.91~1.07; P=0.74) and adverse event rate (risk ratio [RR], teicoplanin vs vancomycin, 0.86; 95% CI, 0.40~1.84; P=0.70). CONCLUSIONS: The meta-analysis results indicate that the two therapies are similar in both efficacy and safety, thus teicoplanin can act as an effective alternative to vancomycin for treating patients infected by MRSA.

According to the fact that the sites of wired video monitoring system cannot move, wiring is not flexible and high network bandwidth is required to transmit video data stream. H.264 video compression standard is adopted, WiFi is introduced as the wireless transmission network, and video coding and compression are produced on embedded S3C6410-based platform, which makes compressed data streams transmitted via WiFi. Based on the above, a wireless video monitoring system is built. It is proved that the site amount of the monitoring system could be increased or decreased in demand and moved arbitrarily through the experiment. Monitor image is clear and stable, and the system could be actually applied in petroleum exploitation, geological exploration, and so on.

Hammer crusher is widely used in cement, ceramic, mining and electricityother industries, hammer head is one of important parts in crusher, its abrasion performance directly affects the service life of hammer crusher and economic cost. According to bimetalcomposite hammer head is often appear “Hammer handle wear and tear”,“Composite difficult” and the set of casting alloy block hammer head set piece of “come off” phenomenon, which design a set piece type bimetal composite casting straight diagonal hammer, make full use of high chromium cast iron wear resistance and the toughness of low alloy steel. Design a protect block structure reasonably that solve the hammer when the actual production of composite interface is difficult to control and “the problem of hammer head wear” for use. Solve the problem of hammer head wear actively, achieve “energy saving, emission reduction and environmental protection”.

The title compound, a GaII dimer, [Ga2Br4(C12H23P)2], was synthesized by reaction of GaBr(THF)n (THF is tetrahydrofuran) with dicyclohexylphosphine in toluene. At 150 K the crystallographically centrosymmetric molecule exhibits disorder in which one of the two independent cyclohexyl groups is modelled over two sites in a 62 (1):38 (1) ratio. In d6-benzene solution, the compound exhibits virtual C2h symmetry as determined by 1H NMR. The coordination environment of the GaII atom is distorted tetrahedral.

This paper studies a novel robotic warehousing system called the overhead robotic compact storage and retrieval system, which can free up the floor space occupation at a low cost. Bins, as basic storage containers, are stacked on top of each other to form a bin stack. Along overhead tracks, bin-picking robots transport bins between storage/retrieval positions and workstations with the aid of track-changing robots. Little research has been done to study operational policies and performance analysis for this new robotic compact warehousing system. We propose a nested queuing network model that considers two transportation resources and performs reinforcement learning using real data to improve the reshuffling efficiency. We find that reinforcement learning based reshuffling policy greatly reduces the reshuffling distance and saves computation time compared to existing policies. We find that the storage policy of stacks affects the optimal width/length ratio regardless of the system height. Interestingly, we obtain the number of robots that can stabilise the system to avoid an explosion of the order queue; two more robots than that number will produce relatively low throughput times. Compared to an AutoStore system, using our system reduces cost by 30% with a slight increase in throughput time. [ABSTRACT FROM AUTHOR]