Financial distress drivers in Brazilian banks: A dynamic slacks approach

This study applies the Dynamic Slacks Based Model (DSBM) developed by Tone and Tsutsui (2010) in order to assess the evolution of input saving/output increasing potentials in major Brazilian Banks from 1996 to 2011. We propose that these potentials or slacks can be used as proxies for an eventual financial distress situation in the future. The main research objective is to determine whether or not different characteristics of bank type – related to ownership, size, and merger and acquisition processes – are significantly related to inefficiency levels and, by extension, to an eventual financial distress situation, since higher inefficiency levels also imply lower input saving/output decreasing potentials. Based on a balanced panel model, secondary data from Economatica were collected and analyzed. Results indicate higher inefficiency levels and slacks in small public and national banks. Policy implications are also addressed.     

Brazilian exchange rate complexity: Financial crisis effects

With the financial market globalization, foreign investments became vital for the economies, mainly in emerging countries. In the last decades, Brazilian exchange rates appeared as a good indicator to measure either investors’ confidence or risk aversion. Here, some events of global or national financial crisis are analyzed, trying to understand how they influenced the “dollar-real” rate evolution. The theoretical tool to be used is the López-Mancini-Calbet (LMC) complexity measure that, applied to real exchange rate data, has shown good fitness between critical events and measured patterns.     

Single-machine scheduling with learning and forgetting effects

Scheduling with learning effects has been widely studied in the past decade. With the increasingly moving toward shorter product cycle times in many production lines, workers in this changeable environment must constantly learn new skill and technology. As a result, the forgetting effect might occur in these situations. In this paper, we propose a model with the consideration of both the learning and forgetting effects. We show some single-machine problems remain polynomially solvable under the proposed model.     

Selling to customers with both Veblen and network effects

For the products that provide not only intrinsic value from their functions but also stylish consumption experience, there often exist both Veblen and network effects. Some customers are more likely to purchase the product if fewer customers can afford it, while others might appreciate the existence of more peers. Focusing on these products, we study the market equilibrium under rational expectations. The optimal pricing and quantity decisions reveal interesting insights about the effects of such mixed consumption externalities.     

标度广义效应代数和标度效应代数的结构

研究了标度广义效应代数与标度效应代数的代数结构,给出了比较完整的结果.通过引入全标度广义代数的概念,本文证明了区间[0,1)上的标度广义效应代数和单位区间[0,1]上的标度效应代数完全由单位区间上的阿基米德余模确定,标度广义效应代数恰同构于全标度广义代数的下集.若标度广义代数满足局部有限条件,则它同构于实数加法群的子群代数.满足(S)条件的标度效应代数同构于实数加法群的子群代数和全标度广义代数的字典序乘积的子代数.     

An improved continuum skin and proximity effect model for hexagonally packed wires

This work presents approximate but closed-form expressions for “effective” complex-valued magnetic permeability and electric conductivity that represent the effects of proximity and skin effect losses in wound coil with hexagonally packed wires. Previous work is extended by providing improved accuracy versus finite element results for effective permeability and by providing an expression for effective conductivity, which was previously neglected. These material properties can then be used in 2D/axisymmetric finite element models in which the coil is modeled as a coarsely meshed, homogeneous region (i.e., removing the need for modeling each turn in the coil).     

Properties and Data Analysis of Order of Addition Designs with Conditions

Order of addition designs with conditions are widely used in experiments, but references on this subject are rather primitive. The paper gives the definition of conditional main effect of pair-wise ordering factor, studies the orthogonality of conditional main effects of pair-wise ordering factors, and proposes the model of order of addition designs with conditions. Finally, it gives the methods for data analysis through two examples.     

基于分形博弈的动量和反转效应转换研究

动量和反转效应普遍存在于证券市场,且会相互转换,但两者间相互转换的特征却鲜有人知.在多数派和少数派博弈的基础上,首次引入分形市场理论对投资者决策特征进行描述,据此建立了分形博弈过程,以分析动量和反转效应转换的统计特征.研究结果表明:在三种博弈机制下,分形博弈机制下的仿真收益率序列的统计分形特征更为接近实际序列的对数收益率序列,且动量和反转效应的相互转换与真实情况也异常相似,这体现了采用分形博弈分析动量和反转效应转换的有效性,为投资者构建有效的动量或反转投资策略提供了决策参考.     

Single-machine scheduling problems with both start-time dependent learning and position dependent aging effects under deteriorating maintenance consideration

In this paper we introduce a new model of joint start-time dependent learning and position dependent aging effects into single-machine scheduling problems. The machine may need maintenance to improve its production efficiency. The objectives are to find jointly the optimal maintenance position and the optimal sequence such that the makespan, the total completion time, and the total absolute deviation of completion times (TADC) are minimized. We also aim to determine jointly the optimal maintenance position, the optimal due-window size and location, and the optimal sequence to minimize the sum of earliness, tardiness and due-window related costs function. We show that all the studied problems can be optimally solved by polynomial time algorithms.     

效应代数的表示

本文讨论了抽象效应代数的表示问题. 对于一个抽象效应代数(E,⊕, 0, 1), 如果存在一个Hilbert 空间 H 和一个单态射 φ:E →ε(H), 那么称 E 为可表示的且称(φ,H) 是E 的一个表示, 其中ε(H) 表示 H 上所有正压缩算子构成的效应代数. 给出了一些可表示的和不可表示的效应代数的例子, 证 明了非空集 X 上的任一模糊集系统 F 和Boolean 代数B_X 都是可表示的效应代数.     

The average value inequality in sequential effect algebras

A sequential effect algebra （E, 0, 1, ,o） is an effect algebra on which a sequential product o with certain physics properties is defined; in particular, sequential effect algebra is an important model for studying quantum measurement theory. In 2005, Gudder asked the following problem： If a, b E （E, 0, 1, , o） and a⊥b and a o b⊥a o b, is it the case that 2（a o b） ≤ a2 b2 ？ In this paper, we construct an example to answer the problem negatively.     

一类与时间干扰效应无关的设计顺序

试验设计方法已在各行各业得到了广泛应用,然而,有些实验往往受到时间趋势干扰效应的影响.讨论了具有与趋势干扰效应无关的设计顺序,借助一类特殊的立体幻方,特别是次幻立方,给出了一类主效应和所有二阶交互效应均与时间干扰效应线性无关的设计顺序,并且该方法针对的因子水平可以是非素数的.     

Learning and forgetting effects on a group scheduling problem

This paper proposes to investigate learning and forgetting effects on the problem of scheduling families of jobs on a single machine to minimize total completion time of jobs. A setup time is incurred whenever the single machine transfers job processing from a family to another family. To analyze the impact of learning and forgetting on this group scheduling problem, we structure three basic models and make some comparisons through computational experiments. The three models, including no forgetting, total forgetting and partial forgetting, assume that the processing time of a job is dependent on its position in a schedule. Some scheduling rules and a lower bound are derived in order to constitute our branch-and-bound algorithm for searching an optimal sequence. In addition, an efficient and simply-structured heuristic is also built to find a near-optimal schedule.     

考虑表面效应的压电半导体梁的静态屈曲行为研究

鉴于表面效应和挠曲电效应对纳米材料或结构的力学行为具有显著影响,以纳米尺度压电半导体(PS)梁为研究对象,根据Hamilton变分原理,推导建立了考虑Steigmann-Ogden表面弹性效应和挠曲电效应的Euler-Bernoulli梁理论模型和相应的边界条件.结合电荷守恒方程和线性漂移扩散方程,研究了该梁结构的静态屈曲行为,得到了短路和开路条件下梁结构的等效弹性常数和屈曲临界压力的解析解.详细分析了表面效应、尺寸效应、挠曲电效应以及载流子屏蔽效应等因素对梁结构的等效弹性常数的影响规律和作用机制.该文的研究结果对基于纳米压电半导体梁结构电子器件的设计和应用具有指导作用.     

Some single-machine scheduling problems with elapsed-time-based and position-based learning and forgetting effects

In this paper, a generalized model with past-sequence-dependent learning and forgetting effects is proposed. Both effects are assumed to be dependent on the sum of processing time as well as the scheduling position. Based on this model, we investigate and prove that some single-machine problems remain polynomially solvable with certain agreeable conditions. We further show that many models known in the literature are special cases of our proposed model. Several helpful lemmas are presented to analyze single-machine scheduling problems with various objective functions: makespan, total completion time, weighted completion time, and maximum lateness.     

关于有限维空间谐振子偶相干态的非经典特性

该文运用数值计算方法研究了有限维希尔伯特空间谐振子偶相干态的非经典特性．研究表明,在有限维情景,偶相干态不仅出现振幅正交分量压缩,而且出现振幅平方压缩和反聚束效应．随着维数ｓ减少,出现两种压缩的区域均缩小且压缩强度减弱;而出现反聚束效应的区域却变大且反聚束程度加强．     

人力资本投资对经济发展的影响研究

从两个方面(依赖关系和制约关系)阐述了人力资本投资对经济的影响作用——拉动作用和推动作用.并通过实例计算了贵州省人力资本投资对当地经济发展的影响作用量等.     

一种对策论模式--足球赛竞争模式

在Lazear和Rosenl981年建立的锦标赛理论(Toumament theory)基础上，进一步讨论两个或多个竞争各自产出(output)面临的生产性效应和破坏性效应(如足球就是以对对方的破坏作为对自己的生产)，加入裁判因素(干扰比赛结果的可能因素)，并将原来的一轮博弈扩展到n轮的假设下所得到的个体行为员优选择。