Urban Social Media Demographics: An Exploration of Twitter Use in Major American Cities

This article explores intersections between place, race/ethnicity, and gender amongst American Twitter users and makes an argument that studying the intensity of tweets provides insights into how and why particular groups tweet. Given recent events in American political life such as the shooting in Ferguson, Missouri and the reactions by young, urban African Americans on Twitter, understanding the role of race, place, gender, and age is important. We observed the time between tweets of urban American Twitter users and explored whether the medium may be providing traditionally marginalized groups, such as young Black men, with potential avenues for mobilizing communication and access to resources.     

1996 editorial: 50th Anniversary Issue of the American Psychologist.

Presents an editorial on the 50th Anniversary Issue of The American Psychologist by the CEO and Executive Vice President of the American Psychological Association. An overview of changes to the journal and the developments in electronic communications pare presented, and the implications for international exchange in scholarly publishing are discussed. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A high-order compact method for nonlinear Black–Scholes option pricing equations of American options

Due to transaction costs, illiquid markets, large investors or risks from an unprotected portfolio the assumptions in the classical Black–Scholes model become unrealistic and the model results in nonlinear, possibly degenerate, parabolic diffusion–convection equations. Since in general, a closed-form solution to the nonlinear Black–Scholes equation for American options does not exist (even in the linear case), these problems have to be solved numerically. We present from the literature different compact finite difference schemes to solve nonlinear Black–Scholes equations for American options with a nonlinear volatility function. As compact schemes cannot be directly applied to American type options, we use a fixed domain transformation proposed by ?ev?ovi? and show how the accuracy of the method can be increased to order four in space and time.     

试论美国动画片《花木兰》中的中国祖先文化

1998年美国迪斯尼动画片以中国北魏时期的民间故事《木兰辞》为素材拍制动画片《花木兰》,一经放映就取得很高关注度,在全世界范围内掀起了中国文化热,其中具有几千年历史的中国祖先文化也贯穿始终。本文对动画片《花木兰》中体现出来的中国祖先文化作简要分析。影片在表面上宣扬和体现了中国祖先文化,但深其本质,影片体现出来的中国祖先文化带有浓重的美国文化元素。     

斐济项目主变压器油的几个重要指标的探讨

对主变压器厂家提交的国产25号变压器油的检测结果进行了分析,对比了国家标准、美国标准和IEC3种标准的不同要求,着重探讨了油的绝缘水平和PCB含量等指标;通过研究,找出了国产变压器油及国标和国际先进标准在上述指标上的差异与差距,为需应用国际标准进行设计的国际工程提供参考经验。     

A new radial basis functions method for pricing American options under Merton's jump-diffusion model

A new radial basis functions (RBFs) algorithm for pricing financial options under Merton's jump-diffusion model is described. The method is based on a differential quadrature approach, that allows the implementation of the boundary conditions in an efficient way. The semi-discrete equations obtained after approximation of the spatial derivatives, using RBFs based on differential quadrature are solved, using an exponential time integration scheme and we provide several numerical tests which show the superiority of this method over the popular Crank–Nicolson method. Various numerical results for the pricing of European, American and barrier options are given to illustrate the efficiency and accuracy of this new algorithm. We also show that the option Greeks such as the Delta and Gamma sensitivity measures are efficiently computed to high accuracy.     

高校英语专业英美文学教学改革探析

随着社会的发展,传统的英语专业英美文学教学模式已不能满足培养21世纪全面发展的外语人才的需要.所以,高校要改革传统的英美文学教学模式,通过改变传统教学方法、提高教师素质和精心选编教材等措施来促进英美文学教学发展.     

中美大学学生管理工作的比较分析

文章对中美大学学生管理工作内容的特点进行了比较，通过对我国高校学生工作现状的分析，借鉴美国高校在学生事务管理方面的先进经验，提出对我国学生管理工作方面的几点意见。     

美国黑人小说的主题嬗变

文章从分析美国黑人文学各个阶段的主要小说入手，以时间为序，结合美国的历史背景，揭示美国黑人小说主题由血泪史到抗议再到自省的嬗变过程，并兼及其艺术手法由现实主义到现代主义的转变。