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991.
In this paper, we present a new learning method using prior information for three-layer neural networks. Usually when neural
networks are used for identification of systems, all of their weights are trained independently, without considering interrelated
weights values. Thus, the training results are usually not good. The reason for this in that each parameter has its influence
on others during learning. To overcome this problem, we first give an exact mathematical equation that describes the relation
between weight values given a set of data conveying prior information. The we present a new learning method that trains part
of the weights and calculates the others using these exact mathematical equations. This method often a priori keeps the given
mathematical structure exactly the same during learning; in other words, training is done so that the network follows a predetermined
trajectory. Numerical computer simulation results are provided to support this approach.
This work was presented, in part, at the Fourth International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–22, 1999. 相似文献
992.
The H∞ almost disturbance decoupling problem is considered. In this paper, a nonlinear design is proposed to find a state feedback controller for bilinear systems. The closed‐loop system is internally stable and achieves disturbance attenuation in nonlinear H∞ sense. We defined a special form of Lyapunov function, which is constructed in terms of one or a set of positive definite constant matrices. If, except of the origin of system, the corresponding polynomial of the positive definite matrix (or several polynomials relevant to the positive definite constant matrices) has (have) no zero on a given subset of state space, then we can construct a controller to solve our problem. It is found that the controller structure could be complicated, but is feasible in computation and may require optimization technique to search the solution. We consider both SIMO and MIMO cases with illustrated examples. 相似文献
993.
994.
水和甲醇存在下MAMS的消失反应动力学研究 总被引:1,自引:0,他引:1
通过实验研究了甲基丙烯酰胺硫酸盐(MAMS)与甲醇、水进行反应的动力学,并对该反应的机理进行了探讨。 相似文献
995.
新铌酸盐化合物K4CuNb8O23及其Cu^2+与Nb^5+的类质同象代换 总被引:5,自引:0,他引:5
1986年Wanklyn等曾报道存在化合物K_5Cu_2Nb_(11)O_(31),并给出其X射线粉晶谱线,但未见进一步指标化和确定其所属晶系及晶胞参数的报道。本研究表明,存在一种新铌酸盐晶体K_4CuNb_8O_(23),其成分及X射线谱异于K_5Cu_2Nb_(11)O_(31)。 用分析纯K_2CO_3、Nb_2O_5及CuSO_4·5H_O按一定比例配制并于1100—1300℃间烧成, 相似文献
996.
Syndiotactic polystyrene (sPS)/nano-CaCO3 composites were prepared on a twin screw extruder for the first time. Differential scanning calorimeter and wide-angle X-ray diffraction were used to investigate the effect of maximum melting temperature (Tmax) and the content of nano-CaCO3 on the crystal forms and melting behavior of sPS for non-isothermal crystallization. The results indicated that the increasing Tmax decreases the crystallization temperature of sPS and facilitates the formation of β-crystal. The addition of nano-CaCO3 changes the melting behavior and crystal form of melt-crystallized sPS and facilitates the formation of β-crystal. The increase in the content of nano-CaCO3 decreases crystallization temperature of sPS and increases the content of β-crystal, which was similar to the effect of increasing Tmax. Pure β-crystal in sPS/nano-CaCO3 composites can be obtained at lower melting temperature due to the effect of nano-CaCO3. 相似文献
997.
998.
立式聚合釜气液传质特性的研究 总被引:2,自引:0,他引:2
本文旨在开发新一代聚四氟乙烯立式反应釜。分别在纯水-氧、乳化剂水溶液-氧两个体系中,用纯氧物理吸收法测定了H/D=1.27的釜的传质容量系数K_La,分析了两体系K_La差别的原因,并对实验结果进行了关联。研究表明,水体系的K_La,是乳液体系的2.5倍,桨型、安装位置等参数对传质有明显影响。在H/D≤1.27的釜中以单层三叶船舶推进器为最佳桨型。 相似文献
999.
ACM/FPM并用胶的性能研究 总被引:2,自引:1,他引:2
对不同比例的国产ACM与FPM的并用胶性能和经济成本进行了研究。并用胶保持了良好的物理机械性能和耐高温老化性能,成本明显低于FPM,加工性能得到改善,具有广阔的应用前景。 相似文献
1000.
Linear relations have been observed between the reciprocal of the noise ratio and the reciprocal of the output power of the He-Cd laser as well as between the noise ratio and the net gain within the laser cavity. By a feedback method with an acoustooptic modulator in the laser cavity at the Brewster angle for low optical loss, a stable laser with high power output and low noise has been obtained. The noise ratio and the output power are 0.8% and 33 mW, respectively, at 4416 A 相似文献