A generalization of the potential function method to multiclass pattern classification†

A generalization of the potential function method is made for multi-class pattern classification. Based on the construction of a set of separation functions an algorithm is proposed for teaching automata to classify various classes of input patterns. Using a basic assumption that the potential functions are bounded and the separation functions can be represented by a linear combination of a set of certain real scalar functions, the convergence of the algorithm is proved.     

A computational method for optimal control problems with a free final time using the modified quasilinearization and the gradient method†

This paper presents a computational method for the solution of a class of optimal control problems with a free final time. The method is based on the combination of the modified quasilinearization and the gradient method. A numerical example is included for illustration.     

THE CURRENT DISTRIBUTION IN THROUGH-HOLE ELECTRODEPOSITION.I:MASS TRANSFER

A realistic representation of through-hole geometry consists of a cylindrical tube with an abrupt decrease in the radius in the middle section of the tube. Fluid flow, mass transfer, and geometric effects were included in modeling through-hole electrodeposition process. The current distribution under mass-transfer limited conditions was computed for both the inside and outside surfaces of a through-hole.     

The effect of in-stent restenosis on hemodialysis access patency

Endovascular stents have recently been shown to extend access patency in thrombosed and stenotic arteriovenous grafts (AVG). Concern remains over the frequency and severity of in-stent restenosis, though this has not been rigorously defined to date. The study was a retrospective analysis of hemodialysis patients referred for access dysfunction during a 2-year period. Using a prospectively collected, vascular access database, we identified 76 patients seen for follow-up angiography due to access dysfunction after stent placement. We compared the effect of in-stent restenosis vs. de novo lesions in patients with previously placed endovascular stents. Measured outcomes were primary assisted patency and frequency of in-stent and de novo lesions. Thirty-five (46.1%) patients had de novo lesions, while 41 (53.9%) had in-stent restenosis. In-stent restenosis was found to be the only factor associated with severity of luminal stenosis (β=0.35, 95% confidence interval 2.21–15.48, P=0.01). In-stent restenosis was associated with increased primary patency among AVGs (hazards ratio 3.10; 95% confidence interval 1.35–7.10; P=0.008). Primary patency of in-stent restenosis vs. de novo lesions for AVGs were respectively: 78% vs. 94% at 1 month, 56% vs. 42% at 3 months, 33% vs. 6% at 6 months. For arteriovenous fistulae, the difference in primary patency of in-stent vs. de novo lesions was not statistically significant. In-stent restenosis is associated with higher percent luminal diameter lesions, while de novo lesions rather than in-stent restenosis are associated with higher risk of AVG access failure and reduced primary patency.     

燃料电池型反应器生产过氧化氢的研究进展

燃料电池型反应器合成过氧化氢是一种环境友好的制备方法.详细地介绍了其工作原理和特点,并阐述了催化剂、电极制备、反应工艺的研究进展,提出了今后工作重点,展望了其发展前景.     

Characterization of three-dimensional multipotent adipose-derived stem cell spheroids

Human adipose stem cells (hADSCs) are reliable sources for cell therapy. However, the clinical applications are limited by the decrease in activity during in vitro culture. We used a knockout serum replacement (KSR) medium, Eppendorf (EP) tube culture, and a simulated microgravity (SMG) culture system to establish hADSC spheroids. We found that hADSCs aggregated and formed spheroids in the KSR culture medium. The EP tube culture method revealed many biological cell characteristics, such as good cell viabilities, rough surfaces, polar growth, fusion phenomenon, and injectability. The findings show its advantages for hADSCs spherical cultures. When cultured in SMG, hADSC spheroids produced large-scale spheroids. Additionally, confocal examination and viability assays revealed that SMG-cultured hADSC spheroids had higher cell viabilities and looser spherical structures, relative to those cultured in EP tubes. hADSC spheroids in static EP tube culture had tighter structures and more dead cells with rough and irregular surfaces, while hADSC spheroids in dynamic SMG condition exhibited looser structures and better cell viabilities with flat and regular surfaces. Therefore, the KSR media promotes spherical formation by hADSCs, which showed polar growth, fusion, and injectability in vitro. The dynamic SMG culture enhances the formation of a looser structure and better cell viabilities for hADSC spheroids.     

THE CURRENT DISTRIBUTION IN THROUGH-HOLE ELECTRODEPOSITION.II: TERTIARY CURRENT DISTRIBUTION

Tertiary current distribution was computed on both the inside and the outside surfaces of a through-hole during electrodeposition. Experiments were conducted in copper deposition at two different copper sulfate solutions. Results were compared with the theoretical calculation.     

A characteristic vector matrix method for multicategory pattern classification†

An algorithm of classifying multicategory patterns using a characteristic vector matrix is described. It is shown that, if the training patterns are linearly separable, the algorithm will guarantee convergence. Furthermore, if the training patterns are not linearly separable, then a method for testing the existence of a limit cycle in the iteration procedure is developed. Examples indicate that the algorithm has rapid convergence and its usefulness is promising. Also a comparison of the convergence condition of the algorithm with that of the fractional correction rule is made.     

Function restoration using linear programming†

This paper presents a method for function restoration using linear programming. It is shown that by defining a suitable error function the function restoration problem can be transformed into a linear programming problem. Furthermore, the error correction algorithms reported in the literature can be derived by minimizing the error function by the steepest-descent method. Numerical examples are given for illustration.     

Multi-model parameter estimation scheme for self-tuning controllers

A multi-model parameter estimation scheme (MMPES) based on a modification of the gaussian sum approach is proposed and its application in self-tuning it-incremental controllers is presented. As shown in the simulation examples, the MMPES gives a fast retuning of the estimated parameters when there is a parameter change; and by preserving the optimal model, it avoids the corruption of the estimated parameters when there is a load change. Thus it is more robust than existing techniques such as the variable forgetting factors. The only penalty in the MMPES is the increase in computing load, yet the proposed MMPES requires substantially less computing effort than that proposed by Andersson (1985).