Using matrices of specifications,factors and concepts to assist design-engineering students

In this work a matrix-type tool is used to assist design-engineering students to develop product design projects. The ‘specifications-factors-concepts matrix’ or SFCM is proposed as a specific tool to organize and relate product requirements, design factors and projected solutions. Taking into account the early stages of the design process, two types of projects that are denominated, respectively, with imposed specifications and with derived specifications, are differentiated. In each case, SFCM conveniently integrates the main contents of the project in order to carry out a comprehensive study of the design problem. SFCM was implemented in higher education, particularly in Degree of Engineering of Industrial Design and Product Development. The design of a hydraulic front brake handle for motorcycles (imposed specifications approach) and a waking up enabler for children (derived specifications approach), were proposed. The process of creation as well as the resulting matrix is shown in each case. In addition, the development and results of the experience are exposed. Students assessed by means of a survey how it helped them to develop the main tasks involved in the design projects giving, globally, a positive opinion about its usefulness.     

Local network externalities and market segmentation

This paper models interaction between groups of agents by means of a graph where each node represents a group of agents and an arc represents bilateral interaction. It departs from the standard Katz–Shapiro framework by assuming that network benefits are restricted only amongst groups of linked agents. It shows that even if rival firms engage in Bertrand competition, this form of network externalities permits strong market segmentation in which firms divide up the market and earn positive profits. The analysis also shows that some graphs or network structures do not permit such segmentation, while for others, there are easy to interpret conditions under which market segmentation obtains in equilibrium.     

The Global Impact of Brexit Uncertainty

We propose a text-based method for measuring the cross-border propagation of large shocks at the firm level. We apply this method to estimate the expected costs, benefits, and risks of Brexit and find widespread reverberations in listed firms in 81 countries. International (i.e., non-U.K.) firms most exposed to Brexit uncertainty (the second moment) lost significant market value and reduced hiring and investment. International firms also overwhelmingly expected negative first-moment impacts from the U.K.'s decision to leave the European Union (EU), particularly related to regulation, asset prices, and labor market impacts of Brexit.     

Timing Equilibria in an Urban Model with Congestion

All spatial urban models with congestion assume that the departure (arrival) time of commutes is exogenously determined and assume that travel speed at a given time and location depends upon the traffic density at that point in time and space. This paper presents a framework that encompasses such models, but allows workers to choose the time at which they leave home (arrive at work). This paper then proves that in general only one equilibrium exists for urban models with traditional congestion technology: a commuting pattern in which commuting is continuous and the rush hour never ends, which is unrepresentative of traffic patterns anywhere. This paper concludes by discussing alternative general equilibrium urban models with congestion that may have more realistic equilibria.     

Supply chain management for small business--how to avoid being part of the food chain

A supply chain is a series of customer and supplier relationships that extend throughout and beyond the company. It is an interwoven set of links that together form a chain supplying our customers in a seamless and integrated fashion delivering a high level of customer satisfaction. Supply chain management (SCM) integrates all activities so they are focused on customer satisfaction (both internally and externally). One of the things this article will attempt to accomplish is to provide a clear understanding of SCM's positive impact on customer service as well as on improving profitability, cash flow, product cycle times, and communication. Whether we go forward in the supply chain to the final end-user or backward in the supply chain to our supplier's suppliers, SCM will significantly improve our ability to serve our customers.     

Noncentral bimatrix variate generalised beta distributions

In this paper, we determine the density functions of nonsymmetrised doubly noncentral matrix variate beta type I and II distributions. The nonsymmetrised density functions of doubly noncentral and noncentral bimatrix variate generalised beta type I and II distributions are also obtained.