Variable step-size affine projection algorithm based on global speech absence probability for adaptive feedbackcancellation简

A novel approach is proposed for improving adaptive feedback cancellation using a variable step-size affine projection algorithm（VSS-APA） based on global speech absence probability（GSAP）.The variable step-size of the proposed VSS-APA is adjusted according to the GSAP of the current frame.The weight vector of the adaptive filter is updated by the probability of the speech absence.The performance measure of acoustic feedback cancellation is evaluated using normalized misalignment.Experimental results demonstrate that the proposed approach has better performance than the normalized least mean square（NLMS） and the constant step-size affine projection algorithms.     

Performance improvement using time delays in multivariable controller design

A new controller for linear multivariable ordinary systems is suggested in which distributed delays are included in the feedback loop. A general design approach to obtain this type of controller is suggested. It is shown that the resulting closed-loop system is asymptotically stable under some sufficient conditions. Sufficient conditions are derived under which the disturbance attenuation, the robustness against parameter variations, and the time-delay stability margins are improved by the proposed controller. The state feedback tracking controller and the dual-state observer are obtained by modification of the proposed controller.     

FROM ARTIFICIAL LIFE TO REAL LIFE: COMPUTER SIMULATION OF PLANT GROWTH∗

Artificial life is by itself an important area of scientific investigation. However, this scientific discipline will be more effective if it can also help one to understand how natural living systems really work. It is argued that plant growth is an area where the studies in artificial life lend themselves to computer modeling of what really happens in nature. An approach for such modeling is described, and the initial results of implementing this approach for a corn plant growth are presented.     

New results for the stability of uncertain time-delay systems

In this paper, based on the Lyapunov stability theorem associated with matrix measure techniques, some new delay-independent criteria for asymptotic stability of linear perturbed time-delay systems are proposed. Furthermore, the stability degree testing problem of the above systems is also investigated. From the given examples, we demonstrate the superiority of these quantitative results by comparing them with other approaches presented in the literature     

Impact of JIT on organizational performance of U.S. firms

This empirical study utilized concrete financial/accounting data concerning measures of organizational performance, as reported in Standard & Poors Compustat, to examine the impact of Just-in-Time production on organizational performance. Matching groups of JIT implementing and non-implementing firms were formed from a cross sectional survey, and a comparative analysis was made for the two groups. The result of the study shows that JIT firms have not achieved better organizational performance in terms of sales in $/employee, operating profit margin, and return on investment than non-JIT firms; but achieved better performances in terms of finished goods inventory turnover, raw materials inventory turnover, and work in process inventory turnover. In addition, this study ascertained that JIT firms have achieved much better performance in terms of quality and flexibility than non-JIT firms.     

Efficiency enhancement of dye-sensitized solar cells with addition of additives (single/binary) to ionic liquid electrolyte

The effect of addition of single and binary additives on the performance of dye-sensitized TiO₂ solar cells based on electrolytes containing an ionic liquid (IL), 1,2-dimethyl-3-propylimidazolium iodide (DMPII) has been studied. Among the seven additives used, the addition of 2-(dimethylamino)-pyridine (DMAP) to IL resulted in best cell efficiency, which showed further enhancement with the addition of 5-chloro-1-ethyl-2-methylimidazole (CEMI) as second additive. The efficiency of the dye-sensitized solar cell (DSC) based on an electrolyte containing binary additives (DMAP and CEMI in equal molar ratios) has been found to increase by 62·5% from 4·35 to 7·07%. The dependence of different photovoltaic performance parameters (V _oc, J _sc, ff, η) of DSC upon temperature has been studied over a 30–120°C range and only a small decrease in conversion efficiency has been observed. The electrolyte containing binary additives (DMAP and CEMI) shows best cell performance up to 120°C.     

SMT production scheduling: a generalized transportation approach

A generalized transportation model is first formulated for the scheduling of Surface Mount Technology (SMT) production. Its dual form is next discussed. By specially coding the SMT scheduling problem, it is unnecessary to develop the constraint matrix for the dual. The simplex method is not applicable for this problem due to its sparse data structure. An efficient algorithm for the dual model is then developed from the idea of the revised simplex method. To illustrate the algorithm, a numeric example is presented.