Nonlinear dynamical systems and inventory management

Surprisingly, deterministic time series can generate highly irregular, random-appearing trajectories. These deterministic time series result from nonlinear dynamical systems of differential or difference equations. The random appearance displayed by these systems is called nonlinear dynamical complexity. Properties of nonlinear complex systems include aperiodic random appearance, sensitive dependence on initial conditions and model parameters, and nonstationarity. Experiments involving the operation of simulated business environments and theoretical nonlinear dynamical models for inventory are reviewed to explore motivating factors that can give rise to demand with nonlinear complexities. The experimental and theoretical evidence reviewed indicates that nonlinear complexities in demand have significant implications for inventory management. Thus, researchers and practitioners in inventory management need to consider these properties when choosing inventory management methods. Characteristics of nonlinear dynamical systems and their implications for inventory management are presented in this paper. The use of the Brock, Dechert, and Scheinkman (1987) (BDS) test for nonlinear dependence is demonstrated on actual demand data.     

Prediction of decomposition limits for ethylene oxide-nitrogen vapor mixtures

A decomposition limit equation applicable to liquid ethylene oxide storage conditions based on recently obtained data is presented. Comparison is made with a second correlation equation developed from literature data. Adjustment of predicted decomposition limits to produce recommended safe operating limits is discussed.     

伦敦交通拥挤的代价

本文通过描述伦敦交通拥挤收费制的起源以及现实中如何克服理论和实践层面的两难实施过程,对道路收费所引致的各种效应进行了论证.作者认为伦敦交通拥挤收费制的引入,应该归功于经济学的贡献,道路定价行动在克服交通拥挤的外部性上,不过是一种应对公众和政治利益诉求的适宜性政策回应.     

Back to literacy

One of the seminal works in the development of British cultural studies was Richard Hoggart's The Uses of Literacy , in which he presents a vision of working class communities in the 40 years since the First World War. To do this he drew particularly on his experiences of Hunslet in South Leeds. In this paper we revisit South Leeds 40 years on to examine continuities and changes in the community as evidenced through people's leisure and compare this with Hoggart's analysis. To do this we have drawn on census and other official statistics and our own observation and interviews in the field. In order to interpret today's communities in South Leeds we make use of theoretical developments in the interim. We suggest that in what Bauman (1997) refers to as ‘two nations society mark two’ people try to reinvent community and it is through leisure in particular that this is evidenced. We therefore conclude that any attempt to understand ‘community’ at the millennium must place leisure centre stage.     

卡耐基梅林大学商学院——防范IT风险泛滥

2007年,两名英国政府官员丢失了一张光盘,内容为2500万居民的个人及银行数据,而这些信息在黑市上价值25亿美元。2008年初,丹麦某数据中心出现了一个微小的失误,致使它的两个客户——某银行ATM网络瘫痪,全国范围内牛奶派送被迫暂停。同年9月,一个网络失误致使伦敦证券交易所全天停止交易活动,     

Fusion of expertise among accounting faculty: towards an expertise model for academia in accounting

This paper aims to portray an accounting faculty expert. It is argued that neither the academic nor the professional orientation alone appears adequate in developing accounting faculty expertise. The accounting faculty expert is supposed to develop into a so-called ‘flexpert’ (Van der Heijden, 2003) who is able to deploy practical accounting exposure in teaching and research. This ‘fusion’ (mix of expertise) resulting from gaining expertise in quite different occupational areas, is attainable at academic career start levels in accounting, where during one's career orientation a professor is both an academic and a professional by training. Fusion is also attainable in complementary competence building wherein the faculty member invests in training and development in the non-core competence domain. The so-called ‘fusion framework’ that is depicted in this contribution could be usefully applied in recruitment efforts of business schools in search of a promising accounting professor.     

Leading the future

This article examines conceptions of leadership appropriate for a global mind set. The financial value of triple bottom line investing is highlighted as an example of this trend. However, this approach is shown to be dependent upon a given society's stage of values development, thus an outcome of more advanced society's citizens having already met basic survival needs, supporting access to higher order values. Constructivist developmental theory is explored and the idea of a global mind set is linked to the emergence of world-centric value systems in individuals. A dialogical approach is introduced, along with Theory U, which is examined in more detail as a process or approach that can facilitate world-centric consciousness. This leads to exploring the perspective and impact of spirituality in relation to leadership appropriate for facilitating a global mind shift.     

Welcome contributor or no price competitor? The competitive interaction of free and priced technologies

The existence of free technologies is prevalent in a variety of industries from software to design. This study examines the competitive interaction between free and priced technologies. I draw on the literature on economic logics to predict that, in general, technologies that are freely shared are likely to stimulate interest and provide useful market information without directly competing with priced technologies. In contrast, due to direct competition, I predict that the prevalence of priced technologies will decrease the sales of other priced technologies. I find support for these hypotheses using a sample of more than 1 million transactions in over 200 distinct markets for MobileApps for the Palm computing platform. This study highlights how free technologies can be utilized to enhance performance of commercial producers. Copyright © 2015 John Wiley & Sons, Ltd.     

Performance deviations and acquisition premiums: The impact of CEO celebrity on managerial risk‐taking

Research summary: This article draws on identity control theory and a study of acquisition premiums to explore how CEO celebrity status and financial performance relative to aspirations affect firm risk behavior. The study finds that celebrity CEOs tend to pay smaller premiums for target firms, but these tendencies change when prior firm performance deviates from the industry average returns, thereby leading these CEOs to pay higher premiums. The study also finds that the premiums tend to be even larger when celebrity CEOs have more recently attained celebrity status. Taken together, these findings contribute to identity control theory and CEO celebrity literatures by suggesting that celebrity status is a double‐edged sword and that the internalization of celebrity status by CEOs strongly influences the decision‐making of CEOs. Managerial summary: The purpose of this article is to examine how CEO celebrity status and financial performance relative to aspirations affect the size of acquisition premiums. The study finds that celebrity CEOs tend to pay smaller premiums for target firms. However, when celebrity CEOs' prior firm performance is either better or worse than the industry average, these CEOs pay higher premiums. This situation is exacerbated when the CEO has only recently been crowned a celebrity. In effect, these CEOs feel great pressure to match the inflated performance expectations that come with celebrity status. These findings suggest that being a celebrity is a double‐edged sword. The implication here is that CEOs who have recently been crowned a celebrity should be aware of these pressures and cope accordingly. Copyright © 2015 John Wiley & Sons, Ltd.