一类二阶不定权特征值问题结点解的全局结构

该文运用分歧方法研究二阶非线性不定权特征值问题u″+rh(t)f(u)=0,0<t<1,u(0)=u(1)=0结点解的全局结构,这里r∈R是参数,权函数h∈C[0,1]可变号.

一类带不定权拟线性椭圆方程组的解

利用临界点理论中的山路引理,讨论一类带不定权拟线性椭圆方程组的Dirichlet问题.借助相应带不定权特征值问题的第一特征值建立了其非平凡解的存在性定理,其中方程组中特征值参数小于某已知常数.

R^2中带不定权与临界位势的非线性椭圆问题

该文讨论了R^2中一类带不定权且含临界位势的二阶椭圆方程的特征值问题,然后,借此特征值问题的第一特征值性质,利用临界点理论及Trudinger-Moser不等式,证明了R^2中一类带不定权且含临界位势的二阶非线性椭圆方程非平凡解的存在性.

一类带不定权函数的奇型Sturm-Liouville算子的局部可定性(英文)

研究一类带不定权函数的奇型Sturm-Liouville算子,给出相应自伴算子在无穷点邻域的局部可定性.

基于GM-RBF不定权组合模型的输电线塔杆倾斜预测分析与应用

为了解决目前输电线塔杆倾斜姿态监测中出现的预测不准确、不及时和预测误报率高等问题,文章提出一种基于灰色模型-径向基函数(grey model-radial basis function,GM-RBF)不定权组合模型的输电线塔杆倾斜姿态预测方法,对昆明市某地区一处输电塔杆200 d的北斗逆向网络载波相位差分技术(real-time kinematic,RTK)数据,使用GM-RBF不定权组合预测模型对铁塔姿态进行预测。该方法不仅能有效规避灰色模型(grey model,GM)自身误差大的缺点,减弱神经网络中训练样本随机性对建模精度的影响,还可以消除因最小二乘定权组合影响整体模型精度的问题。实验表明:对于短期塔杆倾斜预测,GM-RBF不定权组合预测模型在X、Y、P向和倾斜角的预测精度与GM预测精度相当,优于径向基函数(radial basis function,RBF)神经网络模型和GM-RBF定权组合模型的精度;对于长期塔杆倾斜预测,GM-RBF不定权组合模型在X、Y、P向和倾斜角的预测精度分别优于GM预测模型约57.28%、48.07%、43.02%、42.08%,优于RBF预测模型约2.04%、2.31%、3.60%、2.02%,优于GM-RBF最小二乘定权组合模型约2.97%、2.36%、6.23%、4.73%。

一类不定权弹性梁方程的正解

用Leray-Schauder不动点定理,讨论两端简单支撑弹性梁方程u″″+βu″-αu=λa(t)f(u),0<t<1,u(0)=u″(0)=u(1)=u″(1)=0正解的存在性,其中λ是一个正参数,α,β∈R且β<2π2,α≤-β2/4,权函数a:[0,1]→ℝ连续且不定号,f:R^(+)→R连续且f(0)>0.

不定权三阶周期边值问题正解的存在性

本文研究了不定权三阶周期边值问题{u″′(x)+k_(2)u″(x)+k_(1)u′(x)+k_(0)u(x)=λa(x)f(u),x∈(0,1),u^((i))(0)=u^((i))(1),i=0,1,2正解的存在性,其中的参数λ>0,k_(1)∈(0,π^(2)),k_(2)∈(0,+∞),k_(0)=k_(1)k_(2),权函数a∈C([0,1],R)允许变号,f∈C([0,∞),R)且f(0)>0.主要结果的证明基于Leray-Schauder不动点定理.

拆卸与或图生成及其权重不定问题研究

为了高效地规划装配体的拆卸序列,首先利用生成完备可行子装配体的算法构造所有可行的拆卸操作,并以与或图的形式将所有可行的拆卸操作加以表达,对该与或图进行简约,从而构建能够表达所有可行拆卸序列的拆卸与或图;为了基于该拆卸与或图规划拆卸序列,利用广义权重解决了拆卸与或图中有向边上权重不确定的问题,并给出了广义权重的计算方法;最后,通过实例验证了这种拆卸与或图表达拆卸序列的高效性和用于拆卸序列规划的可行性和有效性.结果表明拆卸与或图是一种可用于拆卸序列规划的高效模型.

不定权特征值问题的一个通有性结果

本文应用通有性理论,讨论不定权特征值问题-u″=λ(a(t)u+uf(t,u)),0<t<1,u(0)=u(1)=0的解集结构.这里λ∈R是参数,a∈C[0,1]变号,f:[0,1]×R→R是C^k函数,k≥2,且f(t,0)=0,t∈[0,1].

Approach to obtaining weights of uncertain ordered weighted geometric averaging operator

The ordered weighted geometric averaging（OWGA） operator is extended to accommodate uncertain conditions where all input arguments take the forms of interval numbers. First, a possibility degree formula for the comparison between interval numbers is introduced. It is proved that the introduced formula is equivalent to the existing formulae, and also some desired properties of the possibility degree is presented. Secondly, the uncertain OWGA operator is investigated in which the associated weighting parameters cannot be specified, but value ranges can be obtained and the associated aggregated values of an uncertain OWGA operator are known. A linear objective-programming model is established; by solving this model, the associated weights vector of an uncertain OWGA operator can be determined, and also the estimated aggregated values of the alternatives can be obtained. Then the alternatives can be ranked by the comparison of the estimated aggregated values using the possibility degree formula. Finally, a numerical example is given to show the feasibility and effectiveness of the developed method.

Performance enhancement of IMC-PID controller design for stable and unstable second-order time delay processes

An IMC-PID controller was proposed for unstable second-order time delay system which shows the characteristics of inverse response(RHP zero). A plot of Ms versus λ was suggested to calculate the suitable tuning parameter λ, which provides a trade-off between performance and robustness. Six different forms of process models were selected from literature to show the applicability of the present method. Performance of controller was calculated by ITAE and total variation TV and compared with recently published tuning rules. Undesirable overshoot was removed by using a set-point weighting parameter. Robustness was tested by introducing a perturbation into the various model parameters and closed-loop results show that the designed controller is robust in the case of model uncertainty. The proposed method shows an overall better closed-loop response as compared to other recently reported methods.

Human rights and political and economic instability

The purpose of this paper is to use cross country regression analysis on a large set of countries from around the world for the year 2007 to test the hypothesis that greater instability, political or economic leads to reduced levels of human rights. The results of the paper＇s econometric analysis tend to support the hypothesis that increased levels of either political instability or economic instability are detrimental to human rights within countries.

Reserve estimation of an open pit mine under price uncertainty by real option approach

Reserve estimation is a key to find the correct NPV in a mining project. The most important factor in reserve estimation is the metal price. Metal price fluctuations in recent years were exaggerated, and imposed a high degree of uncertainty to the reserve estimation, and in consequence to the whole mine planning procedure. Real option approach is an efficient method of decision making in the uncertain conditions. This approach has been used for evaluation of defined natural resources projects until now. This study considering the metal price uncertainty used real option approach to prepare a methodology for reserve estimation in open pit mines. This study was done on a copper cylindrical deposit, but the achieved methodology can be adjusted for all kinds of deposits. This methodology was comprehensively described through the examples in such a manner that can be used by the mine planners.

Comparison on global supply chain purchasing strategies based on supply contracts

In the global supply chain in a setting characterized by exchange rate uncertainties,it is quite necessary to focus on comparative research trying to find out which kind of purchasing strategy is better in different situations.The two common global purchasing strategies,risk sharing(RS)and quantity flexibility(QF),are selected to be compared.Using a real-options approach,the valuation models of RS and QF purchasing contracts are established.By means of binomial lattice technique,numerical simulation and sensitivity analysis of two stochastic dynamic programs are presented.The effects on expected discounted value by changing relative parameters are described clearly.Based on comparative analysis,it is concluded that the QF purchasing strategy is better than that of the RS especially where great volatility exists for exchange rate processes in the global supply chain.

Followers of the Social Media Network and National Security

With the social media networks development quickly, the followers of the social media network＇ s behaviors have taken a lot of damagers and threats to national security, and made the nation into unstable situations, even subverted the national sovereignty .This paper analyzes the characters of the followers of the social media in the Ira, Tunisia, Egypt and Libya＇s turmoil, concludes constructive suggestions how to ensure national stability and harmonious development, has some positive effect to our national security.

What Makes a Mother a Monster？ Mrs. Gant＇s Grotesque Masculinity and the Cult of Womanhood

This paper1 reevaluates the portrayal of Mrs. Gant in William Faulkner＇s short story ＂Miss Zilphia Gant＂ （1932）. It argues that Faulkner represents her as ＂the mother as a monster＂ and looks at the features of that representation. More specifically, the paper devotes attention to this abusive mother＇s curious masculinity, employing feminist readings from two angles. That is, on the one hand, the paper reexamines the nature of Mrs. Gant＇s unfemininity by considering the immense responsibility of child-rearing that mothers bear in modern societies. On the other hand, it attempts to locate the origin of her bodily manliness by considering the prism of images of women as evil and destabilizing that pervaded Western culture early in the twentieth century. Such approaches have revealed that making a monster of a mother requires a conspiracy taking advantage of both the inconsistencies inherent in the ideals of motherhood and the bizarre processes through which femininity itself is masculinized. In conclusion, this paper argues that Mrs. Gant＇s monstrosity is a reflection of a predicament which many women in modern times whether Faulkner＇s or our own share, that is, being expected to be a perfect mother while still being viciously castigated as sexually threatening.

一类二阶非线性特征值问题的可解性

运用分歧方法和隐函数定理等工具分别在a(t)不变号和变号两种情形下讨论了非线性特征值问题u″+λa(t)f(u)=0,0<t<1,u(0)=u(1)=0的解集结构,这里λ∈R是实参数,f(0)>0,a∈C[0,1].

Eigenvalue Comparison Theorems on Finsler Manifolds

Cheng-type inequality, Cheeger-type inequality and Faber-Krahn-type inequality are generalized to Finsler manifolds. For a compact Finsler manifold with the weighted Ricci curvature bounded from below by a negative constant, Li-Yau's estimation of the first eigenvalue is also given.

Option Pricing for Coffee Price Using Jump Diffusion Models

In this study,we aim at developing a model for option pricing to reduce the risks associated with Ethiopian coffee price fluctuations.We used daily closed Washed Sidama class A Grade3(WSDA3)coffee price recorded in the period 31 May 2011 to 30 March 2018 obtained from Ethiopia commodity exchange(ECX)market to analyse the price fluctuation.The nature of log-returns of the price is asymmetric(negatively skewed)and exhibits high kurtosis.We used jump diffusion models for modeling and option pricing the coffee price.The method of maximum likelihood is applied to estimate the parameters of the models.We used the root mean square error(RMSE)to test the validation of the models.The values of RMSE for Merton’s and double exponential jump diffusion models are 0.1093 and 0.0783,respectively.These results indicate that the models fit the data very well.We used analytical and Monte Carlo technique to find the call option pricing of WSDA3 price.Based on the empirical results,we concluded that double exponential jump diffusion model is more efficient than Merton’s model for modeling and option pricing of this coffee price.