KMS states on generalised Bunce-Deddens algebras and their Toeplitz extensions

We study the generalised Bunce-Deddens algebras and their Toeplitz extensions constructed by Kribs and Solel from a directed graph and a sequence $\omega$ of positive integers. We describe both of these $C^*$-algebras in terms of novel universal properties, and prove uniqueness theorems for them; if $\omega$ determines an infinite supernatural number, then no aperiodicity hypothesis is needed in our uniqueness theorem for the generalised Bunce-Deddens algebra. We calculate the KMS states for the gauge action in the Toeplitz algebra when the underlying graph is finite. We deduce that the generalised Bunce-Deddens algebra is simple if and only if it supports exactly one KMS state, and this is equivalent to the terms in the sequence $\omega$ all being coprime with the period of the underlying graph.Comment: 30 pages. This version includes a section on the topological graph $E(\infty)$, which allows us to use the work of Katsura to obtain a uniqueness theorem for $C^*(E,\omega)$, and a characterisation of the ideal structure of $C^*(E,\omega)$ when $E$ is finite and strongly connected. The introduction and references have been updated. Minor typos have been correcte

Duality Theory And the Consistent Estimation Of Technological Parameters: Why Cost Function Estimation Can Be Wrong

In this article we show that technological parameter estimates obtained by estimating a cost function that is derivable as the dual of a production function can be biased and inconsistent if the stochastic structure of the model arises from certain types of behavioural assumptions made about rational agents. We consider a specific example in which firms are uncertain about prices. We show that when actual prices differ from expected prices and firms have to make decisions on the basis of their expectations, the inherited stochastic specification of the dual system is highly non-linear in the disturbance terms making consistent parameter estimation impossible by conventional methods. This is demonstrated by a Monte Carlo simulation study of two text-book examples using synthetic data. It is also shown that this type of result can arise when the researcher derives the error structure from the assumption that agents make optimization errors.cost functions; duality; estimation

Information Security In The Age Of Cloud Computing

Information security has been a particularly hot topic since the enhanced internal control requirements of Sarbanes-Oxley (SOX) were introduced in 2002. At about this same time, cloud computing started its explosive growth. Outsourcing of mission-critical functions has always been a gamble for managers, but the advantages of cloud computing are too tempting to ignore. However, the move to cloud computing could prove very costly for a business if the implementation were to fail. When making the decision to outsource critical functions, managers look to accountants to provide assurance that their data and transactions will be secure and that emergency procedures will be in-place and work as designed, to protect the business from any potential losses due to unforeseen events. Statement on Auditing Standards (SAS) 70 has provided guidance to auditors of third-party service organizations since 1992, but was replaced in April 2010 by Statement on Standards for Attestation Engagements (SSAE) 16. And yet, data breaches continue to occur, costing billions of dollars annually. This research used data from the Privacy Rights Clearinghouse (PRC) database and, through frequency analysis, Chi-square and cluster analysis techniques, found statistically significant differences in the frequency of breaches experienced by various types of consumer organizations based on breach and organization type. This result will be useful to auditors. The research also conducted a survey of 67,749 IT manager/directors. The responses to this survey were to be analyzed using binary logistic regressions and Chi-square tests. Unfortunately, due to severe limitations in the response rate and further complicated by the number of incomplete responses, no inferences can be drawn regarding factors relevant to decision-makers when contemplating the movement of critical business functions into the cloud environment

History, College of Agriculture, Agricultural Experiment Station, Agricultural Extension Service, University of Tennessee, 1869-1952

INTRODUCTION: This book is a compilation of articles, bulletins, publications and talks on the history, organization and development of the College of Agriculture, University of Tennessee, in the Land-Grant College System of Education, including Resident Teaching, Research and Extension. Data is also given on the East Tennessee Farmers\u27 Convention, community organizations in Tennessee and the organization and development of the Land-Grant College System of Education. Four copies of this book have been bound and one copy each has been placed in the Agricultural library, the University Library, Office of the Dean and Director of the College of Agriculture and the Office of the Department of Information. Acknowledgement of assistance in the preparation of the data contained in this book is made to former Director C. A, Mooers; Dr. H. A. Morgan, former dean and director, and president of the University; Charles A. Keffer, former director of the Agricultural Extension Service; Fred H. Broome, former Experiment Station editor, and many other past and present members of the College staff

Accuracy of pulse interval timing in ambulatory blood pressure measurement

Blood pressure (BP) monitors rely on pulse detection. Some blood pressure monitors use pulse timings to analyse pulse interval variability for arrhythmia screening, but this assumes that the pulse interval timings detected from BP cuffs are accurate compared with RR intervals derived from ECG. In this study we compared the accuracy of pulse intervals detected using an ambulatory blood pressure monitor (ABPM) with single lead ECG. Twenty participants wore an ABPM for three hours and a data logger which synchronously measured cuff pressure and ECG. RR intervals were compared with corresponding intervals derived from the cuff pressure tracings using three different pulse landmarks. Linear mixed effects models were used to assess differences between ECG and cuff pressure timings and to investigate the effect of potential covariates. In addition, the maximum number of successive oscillometric beats detectable in a measurement was assessed. From 243 BP measurements, the foot landmark of the oscillometric pulse was found to be associated with fewest covariates and had a random error of 9.5 ms. 99% of the cuff pressure recordings had more than 10 successive detectable oscillometric beats. RR intervals can be accurately estimated using an ABPM

Opportunistic detection of atrial fibrillation using blood pressure monitors: a systematic review

Background: Atrial Fibrillation (AF) affects around 2% of the population and early detection is beneficial, allowing patients to begin potentially life-saving anticoagulant therapies. Blood pressure (BP) monitors may offer an opportunity to screen for AF. Aim: To identify and appraise studies which report the diagnostic accuracy of automated BP monitors used for opportunistic AF detection. Methods: A systematic search was performed of the Medline, Medline-in-process and Embase literature databases. Papers were eligible if they described primary studies of the evaluation of a BP device for AF detection, were published in a peer reviewed journal and reported values for the sensitivity and specificity. Included studies were appraised using the QUADAS-2 tool to assess their risk of bias and applicability to opportunistic AF detection. Values for the sensitivity and specificity of AF detection were extracted from each paper and compared. Results and Conclusion: We identified seven papers evaluating six devices from two manufacturers. Only one study scored low risk in all of the QUADAS-2 domains. All studies reported specificity greater than 85% and six reported sensitivity greater than 90%. The studies showed that blood pressure devices with embedded algorithms for detecting arrhythmias show promise as screening tools for AF, comparing favourably with manual pulse palpation. But the studies used different methodologies and many were subject to potential bias. More studies are needed to more precisely define the sensitivity and specificity of opportunistic screening for AF during blood pressure measurement before its clinical utility in the population of interest can be assessed fully

Determining the Anisotropic Exchange Coupling of CrO_2 via First-Principles Density Functional Theory Calculations

We report a study of the anisotropic exchange interactions in bulk CrO_2 calculated from first principles within density functional theory. We determine the exchange coupling energies, using both the experimental lattice parameters and those obtained within DFT, within a modified Heisenberg model Hamiltonian in two ways. We employ a supercell method in which certain spins within a cell are rotated and the energy dependence is calculated and a spin-spiral method that modifies the periodic boundary conditions of the problem to allow for an overall rotation of the spins between unit cells. Using the results from each of these methods, we calculate the spin-wave stiffness constant D from the exchange energies using the magnon dispersion relation. We employ a Monte Carlo method to determine the DFT-predicted Curie temperature from these calculated energies and compare with accepted values. Finally, we offer an evaluation of the accuracy of the DFT-based methods and suggest implications of the competing ferro- and antiferromagnetic interactions.Comment: 10 pages, 13 figure

Simultaneous Multithreading and Hard Real Time: Can It Be Safe?

The applicability of Simultaneous Multithreading (SMT) to real-time systems has been hampered by the difficulty of obtaining reliable execution costs in an SMT-enabled system. This problem is addressed by introducing a scheduling framework, called CERT-MT, that combines scheduling-aware timing analysis with a cyclic-executive scheduler in a way that minimizes SMT-related timing variations. The proposed scheduling-aware timing analysis is based on maximum observed execution times and accounts for the uncertainty inherent in measurement-based timing analysis. The timing analysis is found to work for tasks with and without SMT, though some adjustments are required in the former case. A large-scale schedulability study is presented that shows CERT-MT can schedule systems with total utilizations approaching 1.4 times the core count, without sacrificing safety

Determination of Local Densities in Accreted Ice Samples Using X-Rays and Digital Imaging

At the NASA Lewis Research Center's Icing Research Tunnel ice shapes, similar to those which develop in-flight icing conditions, were formed on an airfoil. Under cold room conditions these experimental samples were carefully removed from the airfoil, sliced into thin sections, and x-rayed. The resulting microradiographs were developed and the film digitized using a high resolution scanner to extract fine detail in the radiographs. A procedure was devised to calibrate the scanner and to maintain repeatability during the experiment. The techniques of image acquisition and analysis provide accurate local density measurements and reveal the internal characteristics of the accreted ice with greater detail. This paper will discuss the methodology by which these samples were prepared with emphasis on the digital imaging techniques