Catálogo de publicaciones - libros

During the experiment for thick test piece with laser coating under multi-impact loads. We discover that the margin of stress force with the form of Total covering is lower than that with the form of partial covering. However, the life of the former is longer than the latter when they are under the same multi-impact stress force action. There will be an intensely deformative hardening and material floating phenomena on the lower part of the edge of covered coating on the basal body of the latter. And the same time, flaw is more easily to come into being and spread at this place, then cause abscission of coat.

A tensile test was carried out for continuous SiC fiber reinforced aluminum matrix composites (SiC/Al), which have different specimen width and length. A Monte Carlo simulation using finite element method was also performed with changing the width and length of composite model. The size effect of strength reliability was examined and discussed. The results showed that composite strength does not appear to have a large change but its reliability is improved with increasing in width of the composite specimen. Also, the composite strength decreases, but Weibull shape parameter has an increase tendency with increasing the gauge length. Effect of specimen width and length on composite strength and its reliability is dependent on the both factors, that is, the incidence of accumulating fracture process, the mean fiber strength and the strength scatter of weaker fibers. The accumulation of the fracture process is related to the fiber stress distribution in the composite.

This study presents a hybrid intelligent approach to model and optimize a seed cleaning/separating process, which separates seeds varying with different types, varieties and lots in a seed cleaner system (5XZW-1.5). In this controlling scheme, the nonlinear system is modeled by Artificial Neural Network, and optimized by Genetic Algorithms. The uniform design is used to sample datasets. Control results suggest that the intelligent approach is useful for the optimization of such a complex process.

In order to improve the mechanical properties of the parts fabricated by Laser Direct Metal Shaping (LDMS), it is of great significance to understand the distribution regularities of transient temperature field during LDMS process. Based on the “element birth and death” technique of finite element method, a three-dimensional multi-track and multi-layer model for the transient temperature field analysis of LDMS is developed by ANSYS Parametric Design Language (APDL) for the first time. In the fabricated model, X-direction parallel reciprocating scanning paths is introduced. Using the same process parameters, the results of simulation show good agreement with the microstructure features of samples which fabricated by LDMS.

Crude oil in the pipeline evaporation is one of hidden safety trouble for directly-fired kiln, which maybe be caused by severe flame deflecting. According to redundancy between technology parameters of furnace, redundancy select majority strategy was proposed, and used as the inference rule of fuzzy observer, the output of the fuzzy observer was tendency of furnace working condition, then it compared with deviation of other local input parameters to diagnose effectively fire deflect and sensors fault. Thus safety and fault-tolerant capacity of furnace are improved, and stronger robustness is also obtained.

Manufacturing Grid (MG) emerges as a new manufacturing model to provide a general platform for networked-manufacturing. The reliability is a significant and complex issue in MG system as resources in it are geographically distributed, heterogeneous and information dynamic in nature, owned by different enterprises or organizations with their own policies. In order to make MG work efficiently, the reliability for MG had been analyzed; a hierarchical evaluation model was proposed. In the end, the use of the model was also presented in system recovery policies.

The risk evaluation is a very important step of decision process of venture capital. This article constructs forewarning risk index systems of venture capital, and applies Artificial Neural Network (ANN) to forecast the latent risk level of venture capital. Empirical analysis indicates that this model could predict the latent risk of venture capital very well.

In order to evaluate accurately the comprehensive performance of assembly packaging ammunition using small samples, a new test and evaluate method is presented. Firstly carry out the consistency test on the performance parameters of electronic parts of ammunition before and after the experiment, which are liable to the influence of various environmental factors, if the result of test is consistent, then firing test is carried out in order to check the reliability of whole ammunition. In the course of the consistency test, according to the difference of electric parameters rank sum test and T-test is used, and the Bayes method is applied in the whole ammunition’s reliability evaluation, and an example is demonstrated in order to verify the validity of this test and evaluation method.

Recently, Support Vector Regression (SVR) has been a popular tool in financial time series forecasting. This study deals with the application of Support Vector Regression in stock composite index forecasting. A preprocessing method for accelerating support vector regression training is presented in this paper. Then we propose a method of support vector regression by modifying the regularized risk function. A data set from Shanghai Stock Exchange is used for the experiments to test the validity of our methods.

In order to apply Manufacturing Grid technology to manufacturing field and provide resource-sharing and collaborating for the distributed manufacturing companies on a common platform, Manufacturing Grid system should resolve the problem brought by non-technical factors in manufacturing. Extending the requirement of product quality and regarding it as a kind of provided service which is required in the process of manufacturing. Then importing the idea of QoS (Quality of Service) to Manufacturing Grid and merging it into the manufacturing’s characteristics. Based on it, making QoS management as the key research contents of Manufacturing Grid and create Manufacturing Grid-QoS (MG-QoS) system. Furthermore, proposing a kind of preliminary solution based on QoS management to Manufacturing Grid’s practical application. It provides quality guarantee for the application of Manufacturing Grid and resolves the issue of prerequisite for Manufacturing Grid’s practice from theoretical research.