This paper presents the results of a study to evaluate the performance of a number of recently proposed semi-active control algorithms for use with multiple MR dampers. A variety of control algorithms used in recent semi-active control studies are considered including the Lyanpunov controller, decentralized bangbang controller, modulated homogeneous friction algorithm, and a clipped optimal controller. Each algorithm is formulated for use with the MR damper. Additionally, each algorithm uses measurements of the absolute acceleration and device displacements for determining the control action to ensure that the algorithms would be implementable on a physical structure. The performance of the algorithms is compared through a numerical example, and the advantages of each algorithm are discussed. The numerical example considers a six story structure controlled with MR dampers on the lower two floors. In simulation, an El Centro earthquake is used to excite the system, and the reduction in the drifts, accelerations, and relative displacements throughout the structure is examined.

Stereoselective glycosylation remains the main challenge in the chemical synthesis of oligosaccharides. Herein we report a simple method to convert thioglycosides into β-sulfonium ions via an intramolecular alkylation reaction, leading to highly α-selective glycosylations for a variety of glycosyl acceptors. The influence of the thioglycoside substituent and the protecting group pattern on the glycosyl donor was investigated and showed a clear correlation with the observed stereoselectivity.

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Automatic VoltageNAR Control (AVC) refers to controlling available reactive resources to correct VoltageNAR problems in Transmission or Distribution systems. Topological connectivity determination is a major component of any AVC application. In general, distribution systems are gigantic, and modeling the whole network is not practical. Therefore, calculating the connectivity of monitored points to available reactive resources in real-time has not been practical. In this paper a template-based modeling is proposed. Using templates it is possible to determine connectivity information with the least amount of modeling and efforts. The connectivity information is then used to calculate proper values of controls to correct the voltage problems identified for the monitored points.