Elaphe subocularis

Number of Pages: 2Integrative BiologyGeological Science

Statistical modelling to predict corporate default for Brazilian companies in the context of Basel II using a new set of financial ratios

This paper deals with statistical modelling to predict failure of Brazilian companies in the light of the Basel II definition of default using a new set of explanatory variables. A rearrangement in the official format of the Balance Sheet is put forward. From this rearrangement a framework of complementary non-conventional ratios is proposed. Initially, a model using 22 traditional ratios is constructed. Problems associated with multicollinearity were found in this model. Adding a group of 6 non-conventional ratios alongside traditional ratios improves the model substantially. The main findings in this study are: (a) logistic regression performs well in the context of Basel II, yielding a sound model applicable in the decision making process; (b) the complementary list of financial ratios plays a critical role in the model proposed; (c) the variables selected in the model show that when current assets and current liabilities are split into two sub-groups - financial and operational - they are more effective in explaining default than the traditional ratios associated with liquidity; and (d) those variables also indicate that high interest rates in Brazil adversely affect the performance of those companies which have a higher dependency on borrowing

Operational research modelling to support healthcare operations management

One often proffered guide for OR model building is that the model should be made as simple as possible subject to meeting its purpose. In healthcare operations management the purpose of an OR model is often to persuade the appropriate stakeholders to modify a system in a way that (hopefully) turns out to be an improvement. Hence the choice of model can be very context-specific, depending very much who needs to be convinced of what. This general issue is examined via a brief description of five different modelling approaches that have been used to support operations management of outpatient clinics. The extent to which the approaches might be 'fit for purpose' in different is discussed

Reflections on queue modelling from the last 50 years

Queueing theory continues to be one of the most researched areas of operational research, and has generated numerous review papers over the years. The phrase 'queue modelling' is used in the title to indicate a more practical emphasis. This paper uses work taken predominantly from the last 50 years of pages of the Operational Research Quarterly and the Journal of the Operational Research Society to offer a commentary on attempts of operational researchers to tackle real queueing problems, and on research foci past and future. A new discipline of 'queue modelling' is proposed, drawing upon the combined strengths of analytic and simulation approaches with the responsibility to derive meaningful insights for managers

Insect (Arthropoda: Insecta) Composition in the Diet of Ornate Box Turtles (Terrapene ornata ornata) in Two Western Illinois Sand Prairies, with a New State Record for Cyclocephala (Coleoptera: Scarabaeidae)

A study of fecal samples collected over a two-year period from juvenile ornate box turtles (Terrapene ornata ornata Agassiz) revealed diets consisting of six orders of insects representing 19 families. Turtles were reared in captivity from eggs harvested from local, wild populations, and released at two remnant prairies. Identifiable insect fragments were found in 94% of samples in 2013 (n=33) and 96% in 2014 (n=25). Frequency of occurrence of insects in turtle feces is similar to results reported in previous studies of midwestern Terrapene species. A comparison of insect composition presented no significant difference between release sites. There is no significant difference in consumed insect species between turtles released into or outside of a fenced enclosure at the same site. Specimens of Cyclocephala longula LeConte collected during this study represent a new state record for Illinois

Liquid drop splashing on smooth, rough and textured surfaces

Splashing occurs when a liquid drop hits a dry solid surface at high velocity. This paper reports experimental studies of how the splash depends on the roughness and the texture of the surfaces as well as the viscosity of the liquid. For smooth surfaces, there is a "corona" splash caused by the presence of air surrounding the drop. There are several regimes that occur as the velocity and liquid viscosity are varied. There is also a "prompt" splash that depends on the roughness and texture of the surfaces. A measurement of the size distribution of the ejected droplets is sensitive to the surface roughness. For a textured surface in which pillars are arranged in a square lattice, experiment shows that the splashing has a four-fold symmetry. The splash occurs predominantly along the diagonal directions. In this geometry, two factors affect splashing the most: the pillar height and spacing between pillars.Comment: 9 pages, 11 figure

Family Business CEO Succession: Examining Personal Retirement Expectations

Retirement well-being expectations of incumbent family owned business CEOs is a critical precursor to successful succession events. The significant antecedents to retirement well-being expectation are family relationships, wealth management and transfer, leadership succession and development, and continuity and viability of the firm. Using data from a survey of 256 family firm CEOs we demonstrate those relationships and show a very strong connection between retirement well-being expectation and firm performance. Study results further our premise that antecedents to retirement well-being expectation are indirectly tied to the overall health and performance of the family firm

Dynamics of grain ejection by sphere impact on a granular bed

The dynamics of grain ejection consecutive to a sphere impacting a granular material is investigated experimentally and the variations of the characteristics of grain ejection with the control parameters are quantitatively studied. The time evolution of the corona formed by the ejected grains is reported, mainly in terms of its diameter and height, and favourably compared with a simple ballistic model. A key characteristic of the granular corona is that the angle formed by its edge with the horizontal granular surface remains constant during the ejection process, which again can be reproduced by the ballistic model. The number and the kinetic energy of the ejected grains is evaluated and allows for the calculation of an effective restitution coefficient characterizing the complex collision process between the impacting sphere and the fine granular target. The effective restitution coefficient is found to be constant when varying the control parameters.Comment: 9 page