Specifying ODP computational objects in Z

The computational viewpoint contained within the Reference Model of Open Distributed Processing (RM-ODP) shows how collections of objects can be configured within a distributed system to enable interworking. It prescribes certain capabilities that such objects are expected to possess and structuring rules that apply to how these objects can be configured with one another. This paper highlights how the specification language Z can be used to formalise these capabilities and the associated structuring rules, thereby enabling specifications of ODP systems from the computational viewpoint to be achieved

Seasonal variation in the health of high-latitude wintering mallards (Anas platyrhynchos)

Thesis (M.S.) University of Alaska Fairbanks, 2017Mallards (Anas platyrhynchos), the most abundant species of dabbling duck in North America, are increasingly wintering in urban centers at latitudes north of their traditional wintering grounds. We captured mallards throughout the non-breeding period in Fairbanks, Alaska in 2012/13 and 2013/14, as well as in Anchorage, Alaska, in 2014/15, to assess seasonal patterns in forage selection and body condition, as well as the influenza A virus (IAV) dynamics within these urban wintering mallard populations. Using stable isotope data (δ13C and δ15N values) from serum and whole blood, we identified seasonal shifts in diet from invertebrates and aquatic vegetation in autumn to anthropogenic food subsidies (i.e. corn and bread) during winter by mallards in both populations. Additionally, mallards wintering in Fairbanks maintained higher body mass levels throughout the winter period than mallards wintering in Anchorage, which declined in mass from autumn to late winter. To study the associated health conditions mallards wintering at these high-latitude locations experience, we examined infection dynamics of influenza A viruses (IAVs), as mallards are considered a natural reservoir host of IAV viruses. We screened mallards for both active infections and prior exposure to IAVs. Molecular screening indicated both IAV prevalence and seroprevalence varied by each season at each site/year. Age differences were pronounced for both infection and immune responses, with juvenile mallards having higher IAV prevalence and adults having higher IAV seroprevalence. Evidence for active infections and antibodies to IAVs were detected throughout each sampling year at both locations. Variability in mallard immune responses, suggests individual heterogeneity in the timing of infections and duration of immune responses to IAVs across the non-breeding period. Thus, the combination of these findings provide valuable information about when mallards may be relying most on anthropogenic food subsidies and the potential for these populations to serve as biotic reservoirs for IAVs throughout the non-breeding period. Wildlife management agencies may consider these data when developing management objectives or regulations concerning these urban wintering mallard populations.Chapter 1. Use of anthropogenic food subsidies by two high-latitude wintering mallard (Anas platyrhynchos) populations -- Chapter 2. Maintenance of low-pathogenic influenza A viruses and antibody response in high-latitude urban wintering mallards (Anas platyrhynchos) -- General Conclusions -- Appendices

Spectral convergence in tapping and physiological fluctuations: coupling and independence of 1/f noise in the central and autonomic nervous systems.

When humans perform a response task or timing task repeatedly, fluctuations in measures of timing from one action to the next exhibit long-range correlations known as 1/f noise. The origins of 1/f noise in timing have been debated for over 20 years, with one common explanation serving as a default: humans are composed of physiological processes throughout the brain and body that operate over a wide range of timescales, and these processes combine to be expressed as a general source of 1/f noise. To test this explanation, the present study investigated the coupling vs. independence of 1/f noise in timing deviations, key-press durations, pupil dilations, and heartbeat intervals while tapping to an audiovisual metronome. All four dependent measures exhibited clear 1/f noise, regardless of whether tapping was synchronized or syncopated. 1/f spectra for timing deviations were found to match those for key-press durations on an individual basis, and 1/f spectra for pupil dilations matched those in heartbeat intervals. Results indicate a complex, multiscale relationship among 1/f noises arising from common sources, such as those arising from timing functions vs. those arising from autonomic nervous system (ANS) functions. Results also provide further evidence against the default hypothesis that 1/f noise in human timing is just the additive combination of processes throughout the brain and body. Our findings are better accommodated by theories of complexity matching that begin to formalize multiscale coordination as a foundation of human behavior

Specifying ODP Computational Objects in Z

The computational viewpoint contained within the Reference Model of Open Distributed Processing (RM-ODP) shows how collections of objects can be configured within a distributed system to enable interworking. It prescribes certain capabilities that such objects are expected to possess and structuring rules that apply to how these objects can be configured with one another. This paper highlights how the specification language Z can be used to formalise these capabilities and the associated structuring rules, thereby enabling specifications of ODP systems from the computational viewpoint to be achieved

Economic Value Added (EVA) and the Valuation of Small Businesses

This article presents an overview of the standard asset, market, and income valuation methods generally used to estimate the value of small businesses

Value Creation and the Entrepreneurial Business

The need to finance high growth and manage the interests and needs of investors makes value creation a critical concern for entrepreneurial businesses. Almost any financial endeavor, such as attracting new investors or making investment decisions, necessitates the consideration of the equity value created by the endeavor. The perceived value creation, for example, has a direct effect on the percentage of the firm outside investors will require if they are to invest in the business. Measuring the value created by publicly traded businesses, depending on the assumptions made, is relatively straightforward. If public markets are at least semi-strong form efficient (i.e., equity prices reflect all publicly available information regarding a business’s true underlying value), then the closing price on a large, publicly-traded company should accurately reflect that enterprise’s value. In other words, public markets take individual investors’ beliefs of the magnitude, timing and riskiness of the business’s expected future cash flows and incorporate them into the actual equity value reported at closing. Like the managers of large companies, the entrepreneur should think market value, rather than just accounting profits, when making economic decisions. Unfortunately, the major problem of measuring the value of an entrepreneurial business is that many are either privately-owned or are publicly-traded in very thin secondary markets, subsequently market assessment of the true value of the business’s equity is not readily available. This unavailability of market information makes the value creation assessment process more difficult for entrepreneurial companies, but certainly not any less important. Thus, information about the correlation of readily available performance measures with a true market value creation measure is worthwhile. This study statistically examines the relationship of non-market measures of value creation with a true market value creation measure for a sample of small publicly-traded companies (i.e., less than $100 million). We restricted the size of the companies we examined to make our sample more representative of entrepreneurial businesses, which are more likely to be either privately-held or traded very thinly in public markets. For the purposes of this study the market value creation measure utilized was shareholder return. Each company’s shareholder return was estimated using stock price and dividend information. Three different dimensions of non-market value creation measures were utilized. These three dimensions were accounting profitability, cash flow performance, and growth. Our investigation revealed that relationships between certain non-market measures of value and small entrepreneurial types of businesses existed. Statistically significant positive correlations were found between shareholder return and the earnings profitability measures of return on equity, return on assets and return on invested capital. These relationships were found to exist only for companies that reported positive earnings. Stronger relationships were found to exist between shareholder return and the cash flow performance measures of earnings growth and sales growth. Furthermore, the sales growth measure was found to be correlated for companies that had positive earnings and companies that reported negative earnings

Z2SAL: a translation-based model checker for Z

Despite being widely known and accepted in industry, the Z formal specification language has not so far been well supported by automated verification tools, mostly because of the challenges in handling the abstraction of the language. In this paper we discuss a novel approach to building a model-checker for Z, which involves implementing a translation from Z into SAL, the input language for the Symbolic Analysis Laboratory, a toolset which includes a number of model-checkers and a simulator. The Z2SAL translation deals with a number of important issues, including: mapping unbounded, abstract specifications into bounded, finite models amenable to a BDD-based symbolic checker; converting a non-constructive and piecemeal style of functional specification into a deterministic, automaton-based style of specification; and supporting the rich set-based vocabulary of the Z mathematical toolkit. This paper discusses progress made towards implementing as complete and faithful a translation as possible, while highlighting certain assumptions, respecting certain limitations and making use of available optimisations. The translation is illustrated throughout with examples; and a complete working example is presented, together with performance data

A Class of Transformations for Box‐Jenkins Seasonal Models

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147030/1/rssc00953.pd

An Improved Algorithm for Generating Database Transactions from Relational Algebra Specifications

Alloy is a lightweight modeling formalism based on relational algebra. In prior work with Fisler, Giannakopoulos, Krishnamurthi, and Yoo, we have presented a tool, Alchemy, that compiles Alloy specifications into implementations that execute against persistent databases. The foundation of Alchemy is an algorithm for rewriting relational algebra formulas into code for database transactions. In this paper we report on recent progress in improving the robustness and efficiency of this transformation