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This study considers the observer-based consensus tracking problem of linear multi-agent systems with input saturation. Existing observer-based consensus protocols are designed based on an undirected graph, and need global information, such as the network size or eigenvalue information of the Laplacian matrix. In this study, based on only the agent dynamics and the relative outputs of neighbouring agents, an adaptive consensus protocol is proposed by assigning a time-varying coupling weight to each node, and this protocol is independent of any global information and hence is fully distributed. Under the assumptions that each agent is asymptotically null controllable with bounded controls and detectable, and the topological graph has a directed spanning tree with the leader as the root node, semi-global observer-based consensus tracking of multi-agent systems can be reached despite actuator saturation occurring. The results are applied to consensus tracking control of two-mass-spring systems, which are well-known models for vibration in many mechanical systems. [ABSTRACT FROM AUTHOR]

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A new spike sorting method based on the support vector machine (SVM) is proposed to resolve the superposition problem. The spike superposition is generally resolved by the template matching. Previous template matching methods separate the spikes through linear classifiers. The classification performance is severely influenced by the background noise included in spike trains. The nonlinear classifiers with high generation ability are required to deal with the task. A multi-class SVM classifier is therefore applied to separate the spikes, which contains several binary SVM classifiers. Every binary SVM classifier corresponding to one spike class is used to identify the single and superposition spikes. The superposition spikes are decomposed through template extraction. The experimental results on the simulated and real data demonstrate the utility of the proposed method. [ABSTRACT FROM AUTHOR]

The electrophilic cyclization of 1,2-allenic phosphonates with in-situ-generated PhTeX to afford 4-(phenyltelluro)-2-methoxy-2,5-dihydro[1,2]-oxaphosphole 2-oxides was studied. Good yields were observed when PhTeBr was used as the electrophilic reagent. The stereochemistry of the reaction is also discussed in the paper. [ABSTRACT FROM AUTHOR]

A macrokinetic model for a myeloma cell line is proposed. The model describes the dynamic balances of lactate, alanine, ATP and NADH during the metabolsim of glucose, glutamine and other amino acids. The metabolic pathways mainly include glycolysis, glutaminolysis, the trcicarboxylic acid cycle, the formation and utilization of amino acids, the respiratory chain, cell growth and cell death. The metabolic shift of glucose is especially considered because of a change in the rate of glycolysis. Thus the model functions in three modes to describe the behaviour of the myeloma cell line. On the basis of this model the macrokinetic bioreaction rates such as the specific substrate consumption rate, the specific growth rate, the specific acetyl-CoA formation rate, as well as the specific oxygen uptake rate, are estimated. The specific substrate consumption rate and the specific growth rate are then coupled into a bioreactor model such that the key variables, i.e., the cell density, the substrate and metabolite concentrations, are obtained. Experiments with batch and fed-batch cultures of a myeloma cell line (X63-Ag8.653) were used to validate the model. The prediction of the model was simulated by the rolling prediction approach. [ABSTRACT FROM AUTHOR]

In the polymerase chain reaction (PCR), the reference temperature profiles of thermal cycling must be tracked rapidly and precisely so as to amplify DNA in samples, strictly following the exponential function of 2n (n: thermal cycles) as quickly as possible. For this purpose, a model based hybrid controller to follow up setpoint changes is developed which is easily implemented with a microcomputer ADuC834 for its simple configuration and low cost of computation. The hybrid control strategy combines feedforward, feedback, and Bang‐Bang actions to achieve better setpoint response and steady state behavior. Based on the steady state model of the thermocycler, the feedforward action serves as the model predictive control for each setpoint, while the feedback controller is used as the local control action to accelerate ramp rates and reduce the tracking errors. The model of the thermocycler is identified with step response data at different operation regions. Experimental results demonstrate that, besides the improvement of the tracking accuracy, both the rise time and the decay time of each thermal cycle have been reduced significantly with the hybrid control strategy, compared with the conventional PID. Therefore, improved efficiency and accuracy of the polymerase chain reaction is achieved. [ABSTRACT FROM AUTHOR]