Optimal operation of hydrothermal systems with Hydrological Scenario Generation through Bootstrap and Periodic Autoregressive Models

In electrical power systems with strong hydro generation, the use of adequate techniques to generate synthetic hydrological scenarios is extremely important for the evaluation of the ways the system behaves in order to meet the forecast energy demand. This paper proposes a new model to generate natural inflow energy scenarios in the long-term operation planning of large-sized hydrothermal systems. This model is based on the Periodic Autoregressive Model, PAR (p), where the identification of the p orders is based on the significance of the Partial Autocorrelation Function (PACF) estimated via Bootstrap, an intensive computational technique. The scenarios generated through this new technique were applied to the operation planning of the Brazilian Electrical System (BES), using the previously developed methodology of Stochastic Dynamic Programming based on Convex Hull algorithm (SDP-CHull). The results show that identification via Bootstrap is considerably more parsimonious, leading to the identification of lower orders models in most cases which retains the statistical characteristics of the original series. Additionally it presents a closer total mean operation cost when compared to the cost obtained via historic series.     

Convex Parametric Programming in Abstract Spaces

This article studies stability and optimality for convex parametric programming models in abstract spaces. Necessary conditions for continuity of the feasible set mapping are given in complete metric spaces. This continuity is characterized for models in which the space of decision variables is reflexive Banach space. The main result on optimality characterizes locally optimal parameters relative to stable perturbations of the parameter. The result is stated in terms of the existence of a saddle-point for a Lagrangian that uses a finite Borel measure. It does not hold for unstable perturbations even if the model is finite dimensional. The results are applicable to various formulations of control and optimal control problems.     

Optical design and multi-objective optimization with fuzzy method for miniature zoom optics

In this paper a thinning L-type zoom lens design was proposed to exploit the reflecting and refracting surfaces connected by a prism. However, in the L-type designs, the modulation transfer function (MTF) value is comparatively low compared with that in its coaxial counterparts. If we increase the MTF, that would cause the relative illuminace (RI) degradation. We propose a combination of the Taguchi method and fuzzy approach to improve both the RI and MTF in L-type zoom systems. The resulting experimental values of orthogonal array L9 of the Taguchi method were used as inputs for fuzzy approach to obtain the MPCI value. The MPCI value was then analyzed by variance, revealing that the two most significant factors were (1) the surface 7 to image length and (2) the semi-aperture of the front element. In our proposed method, the appropriate weight of MTF and RI for the inputs of fuzzy controllers increased the MTF by 3.74%, but the RI only reduced by 0.13% in the systematic wide-angle end, respectively.     

Automated prover for attribute dependencies in data with grades

We present a new axiomatization of logic for dependencies in data with grades, which includes ordinal data and data over domains with similarity relations, and an efficient reasoning method that is based on the axiomatization. The logic has its ordinary-style completeness characterizing the ordinary, bivalent entailment as well as the graded-style completeness characterizing the general, possibly intermediate degrees of entailment. A core of the method is a new inference rule, called the rule of simplification, from which we derive convenient equivalences that allow us to simplify sets of dependencies while retaining semantic closure. The method makes it possible to compute a closure of a given collection of attributes with respect to a collection of dependencies, decide whether a given dependency is entailed by a given collection of dependencies, and more generally, compute the degree to which the dependency is entailed by a collection of dependencies. We also present an experimental evaluation of the presented method.     

Generalized valuations on MTL-algebras

In this paper, we study some kinds of generalized valuations on MTL-algebras, discuss the relationship between the cokernel of generalized valuations and types of filters on MTL-algebras. Then, we give some equivalent characterizations of positive implicative generalized valuations on MTL-algebras. Finally, we characterize the structure theory of quotient MTL algebras based on the congruence relation, which is constructed by generalized valuations. The results of this paper not only generalize related theories of generalized valuations, but also enrich the algebraic conclusion of probability measure, on algebras of triangular norm based fuzzy logic.     

地下工程围岩分类模糊推理系统设计

将现场获取的影响地下工程围岩分类的几种主要因素视为判别围岩类别论域上的模糊子集,利用建立的地下工程围岩分类模糊逻辑推理系统对围岩类别进行模糊逻辑推理运算,获得与实际情况相一致的围岩类别的判定,直接为地下工程的信息化设计和施工提供依据。     

求解非线性规划的序列有理规划SRP方法

基于分子、分母皆线性的两点有理逼近，本文对于非线性规划提出了序列有理规划ＳＲＰ方法，按两种情况进行了研究。第一种为ＳＲＰ－Ｌ方法，将原问题化为等效的ＬＰ问题求解；第二种为ＳＲＰ－Ｑ方法，将原问题化为等效的ＱＰ问题求解。本文的工作说明，两点有理逼近函数对于改进优化方法是有益的。     

空化起始的理论预测——模糊空化系统

木文建立了一个模糊空化系统、运用模糊数学的理论对空化起始问题进行了理论预测、根据反映空化核群空化行为的四个空化特征值和由试验得出的一些定性规律,用模糊理论的方法得出控制系统空化状态的模糊状态转移矩阵,从而估算出系统的空化状态。用本文所提出的方法对两种轴对称头体的空化起始进行了预测。所得的结果与相应的试验结果相当满意地符合。     

极限分析的无搜索数学规划算法

本文研究理想刚塑性介质极限载荷因子的计算方法。根据极限分权理论的上限定理,建立了计算极限载荷因子的一般数学规划有限元格式。针对这种格式的特点,提出了一个求解极限载荷因子的无搜索迭代算法。这个算法中采用逐步识别刚性、塑性分区,不断修正目标函数的方案,克服了目标函数非光滑所导致的困难。本文提出的算法建立于位移模式有限元基础上,有较广的适用范围,且具有计算效率高,稳定性好,格式简单易于程序实现等优点。