A new procedure for steepest ascent

The procedure of steepest ascent consists of performing a sequence of sets of trials. Each set of trials is obtained as a result of proceeding sequentially along the path of maximum increase in response. Until now there has been no formal stopping rule, When response values are subject to random error, the decision to stop can be premature due to a “false” drop in the observed response.

A new stopping rule procedure for steepest ascent is intro-duced that takes into account the random error variation in response values. The new procedure protects against taking too many observations when the true mean response is decreasing, it also protects against stopping. prematurely when the true mean response is increasing, A numerical example is given which illus-trates the method.     

A Parameter-Tuned Genetic Algorithm for Economic-Statistical Design of Variable Sampling Interval X-Bar Control Charts for Non-Normal Correlated Samples

Among innovations and improvements that occurred in the past two decades on the techniques and tools used for statistical process control (SPC), adaptive control charts have shown to substantially improve the statistical and/or economical performances. Variable sampling intervals (VSI) control charts are one of the most applied types of the adaptive control charts and have shown to be faster than traditional Shewhart control charts in identifying small changes of concerned quality characteristics. While in the designing procedure of the VSI control charts the data or measurements are assumed independent normal observations, in real situations the validity of these assumptions is under question in many processes. This article develops an economic-statistical design of a VSI X-bar control chart under non-normality and correlation. Since the proposed design consists of a complex nonlinear cost model that cannot be solved using a classical optimization method, a genetic algorithm (GA) is employed to solve it. Moreover, to improve the performances, response surface methodology (RSM) is employed to calibrate GA parameters. The solution procedure, efficiency, and sensitivity analysis of the proposed design are demonstrated through a numerical illustration at the end.     

从行为经济学透视消费者非理性购买决策的涵义

非理性购买行为现象非常普遍,但关于非理性购买决策的定义目前并没有一个统一的说法。行为经济学是一门介于经济学和心理学之间的边缘科学,它从心理学的角度揭示了人类非理性决策的现实,对规范经济学的“经济人”假设提出了挑战,动摇了效用最大化公理,它用实验方法证明现实生活中的人如何做出经济决策,使经济学恢复它本来的面目。基于规范经济学和行为经济学中关于“人性”假说的对比研究,发现非理性购买决策是指人们在购买过程中依靠直觉或情感、违反效用最大化、偏好不一致和非完全自利的判断与选择行为。     

WOUND,SURFACE, SKIN

The essay draws on four recent artworks which have been highly controversial or visible in South Africa since 2010, in order to explore concepts of wounding and political autopsy on the one hand, and of skin surface on the other. The discussion aims to elaborate on and render increasingly complex both the wounds that won't heal, and which erupt into public life through responses to artworks, and the healing over of a wound along a skin surface which artists are exploring in its multiple senses of a cover, a form of cladding, and as a membrane of feeling. Each of the artworks imply a complex relationship between the domains of public and private, and invoke the intimate, or sites of vulnerability, including the dead body, as a means of reimagining the social. They draw on histories of violence to re-compose the aesthetic project: histories of violence, that is, are resisted, forced open, surrendered to, and generative of unforeseen subjectivities.     

基于正交试验法研究乳化炸药螺杆泵螺杆加工三要素

针对主轴转速、进给速度、背吃刀量切削三要素不同值影响螺杆表面粗糙度规律,剖析传统的依靠人工经验选择三要素存在人为缺陷及遗传算法优化选择三要素需大而全的数据库难以实现的现状,探讨一种科学简单、易于实现的正交试验法应用于筛选三要素的优化组合,通过设计3因素3水平试验并对数据进行数理统计分析计算,得出三要素中背吃刀量对螺杆表面质量影响最显著,主轴转速对其影响非显著的结论,研究出的三要素最优值组合能确保螺杆加工表面质量、提高工效,对实际生产具有一定的指导意义。     

Emotional labour profiles: Associations with key predictors and outcomes

ABSTRACT

The present study examines how three emotional labour strategies (hiding feelings, faking emotions, and deep acting) combine within different profiles of workers among two samples characterised by different types and intensity of customer contact. In addition, this research investigates the role of perceived workload as well as perceived organisational support, supervisor support, and colleagues support in the prediction of profile membership. Finally, this research also documents the relation between emotional labour profiles and adaptive and maladaptive work outcomes (job satisfaction, work performance, emotional exhaustion, sleeping problems, psychological detachment, and counterproductive work behaviours). Latent profile analysis revealed three similar emotional labour profiles in both samples. Results also showed the most desirable levels on all outcomes to be associated with Profile 3 (Low Emotional Labor/Low Surface Acting and Moderate Deep Acting), followed by Profile 2 (Moderate Emotional Labor/Moderate Surface Acting and High Deep Acting) and Profile 1 (High Emotional Labor), with most comparisons being statistically significant in both samples. In contrast, a more diversified pattern of findings was observed in the prediction of profile membership. For instance, perceived colleagues support did not predict membership into any of the profiles, while supervisor support predicted an increased likelihood of membership into Profile 3 relative to Profiles 1 and 2.     

气-液界面上TTAB水溶液动态表面张力的研究

滴体积法测定30℃时气-液界面上十四烷基三甲基溴化铵(TTAB)水溶液的动态表面张力.根据动态表面张力随浓度的变化规律研究TTAB分子的吸附动力学.发现在气-液两相界面上,TTAB分子的吸附机理与溶液浓度有关.在小于CMC的极低浓度时,TTAB水溶液的吸附为纯扩散控制机理.随浓度增大,吸附机理由纯扩散控制转变为受扩散-动力学控制.     

高温超导薄膜微波表面电阻测试方法的改进

介绍了一种12GHz附近的高温超导薄膜微波表面电阻Rs测试系统。该系统采用低损耗高介电常数的蓝宝石,构成工作在TE011 δ谐振模式的介质谐振器,在77K时,利用测量介质谐振器的Q值得到单片高温超导薄膜的微波表面电阻Rs。分析了其耦合装置对校准物理模型的影响,通过改进耦合装置可提高系统测试的准确度。该系统与前三代测试系统进行比较,其测试准确度有明显地提高。     

用直观的方法讲述等压面与等压线及其关系

等压面和等压线问题是《气象学与气候学》课程教学中比较抽象难懂且非常重要的一部分内容,本文试图采用立体图、垂直剖面图、水平剖面图三位一体的直观教学方法来讲述该问题,使问题由抽象囊为直观、由难变易,最终使问题迎刃而解。     

Statistical inference for the effect of magnetic brain stimulation on a motoneurone

A stochastic model is developed for the possible excitatory and inhibitory effects of a stimulus to the brain on the activity of single human motoneurones. The model consists of a Wiener process for the build-up of underlying potential, a deterministic effect due to the stimulus and a random lag from brain to muscle. Direct likelihood inference for its parameters seems impossible, and we study the use of simulation to estimate the log-likelihood for the parameters of substantive interest. Monte Carlo methods yield point and confidence interval estimates of the membrane excitability underlying excitatory and inhibitory effects. The main qualitative conclusion is that both excitatory and inhibitory effects are unambiguously present. The contribution of statistical analysis to this problem is to provide accurate and apparently reliable inference for the quantities of neurophysiological interest. More generally, our methodology has the potential to make accurate likelihood-based inferences in challenging problems, but the computational burden can be large, particularly if the model is not fully adequate for the data, as in our application.