There is increasing concern that most current published research findings are false. The probability that a research claim is true may depend on study power and bias, the number of other studies on the same question, and, importantly, the ratio of true to no relationships among the relationships probed in each scientific field. In this framework, a research finding is less likely to be true when the studies conducted in a field are smaller; when effect sizes are smaller; when there is a greater number and lesser preselection of tested relationships; where there is greater flexibility in designs, definitions, outcomes, and analytical modes; when there is greater financial and other interest and prejudice; and when more teams are involved in a scientific field in chase of statistical significance. Simulations show that for most study designs and settings, it is more likely for a research claim to be false than true. Moreover, for many current scientific fields, claimed research findings may often be simply accurate measures of the prevailing bias. In this essay, I discuss the implications of these problems for the conduct and interpretation of research.

Why most published research findings are false

Modern networks provide a variety of interrelated services including routing, traffic monitoring, load balancing, and access control. Unfortunately, the languages used to program today's networks lack modern features - they are usually defined at the low level of abstraction supplied by the underlying hardware and they fail to provide even rudimentary support for modular programming. As a result, network programs tend to be complicated, error-prone, and difficult to maintain.This paper presents Frenetic, a high-level language for programming distributed collections of network switches. Frenetic provides a declarative query language for classifying and aggregating network traffic as well as a functional reactive combinator library for describing high-level packet-forwarding policies. Unlike prior work in this domain, these constructs are - by design - fully compositional, which facilitates modular reasoning and enables code reuse. This important property is enabled by Frenetic's novel run-time system which manages all of the details related to installing, uninstalling, and querying low-level packet-processing rules on physical switches.Overall, this paper makes three main contributions: (1) We analyze the state-of-the art in languages for programming networks and identify the key limitations; (2) We present a language design that addresses these limitations, using a series of examples to motivate and validate our choices; (3) We describe an implementation of the language and evaluate its performance on several benchmarks.

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Frenetic: a network programming language

Thank you for downloading some basic problems of the mathematical theory of elasticity. As you may know, people have search hundreds times for their favorite readings like this some basic problems of the mathematical theory of elasticity, but end up in infectious downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they cope with some infectious bugs inside their computer.

Some Basic Problems Of The Mathematical Theory Of Elasticity

A Combinatory Logic

A thorough understanding of optical properties of biological tissues is critical to effective treatment planning for therapies such as photodynamic therapy (PDT). In the last two decades, new technologies, such as broadband diffuse spectroscopy, have been developed to obtain in vivo data in humans that was not possible before. We found that the in vivo optical properties generally vary in the ranges μ(a) = 0.03-1.6 cm⁻¹ and μ'(s) = 1.2-40 cm⁻¹, although the actual range is tissue-type dependent. We have also examined the overall trend of the absorption spectra (for μ(a) and μ'(s)) as a function of wavelength within a 95% confidence interval for various tissues in vivo. The impact of optical properties on light fluence rate is also discussed for various light application geometries including superficial, interstitial, and within a cavity.

/pdf/a-review-of-in-vivo-optical-properties-of-human-tissues-and-4sa3qlende.pdf

A review of in-vivo optical properties of human tissues and its impact on PDT

Functional Reactive Programming (FRP) extends a host programming language with a notion of time flow. Arrowized FRP (AFRP) is a version of FRP embedded in Haskell based on the arrow combinators. AFRP is a powerful synchronous dataflow programming language with hybrid modeling capabilities, combining advanced synchronous dataflow features with the higher-order lazy functional abstractions of Haskell. In this paper, we describe the AFRP programming style and our Haskell-based implementation. Of particular interest are the AFRP combinators that support dynamic collections and continuation-based switching. We show how these combinators can be used to express systems with an evolving structure that are difficult to model in more traditional dataflow languages.

Functional reactive programming, continued

Functional reactive programming, or FRP, is a paradigm for programming hybrid systems – ie, systems containing a combination of both continuous and discrete components – in a high-level, declarative way The key ideas in FRP are its notions of continuous, time-varying values, and time-ordered sequences of discrete events Yampa is an instantiation of FRP as a domain-specific language embedded in Haskell This paper describes Yampa in detail, and shows how it can be used to program a particular kind of hybrid system: a mobile robot Because performance is critical in robotic programming, Yampa uses arrows (a generalization of monads) to create a disciplined style of programming with time-varying values that helps ensure that common kinds of timeand space-leaks do not occur No previous experience with robots is expected of the reader, although a basic understanding of physics and calculus is assumed No knowledge of arrows is required either, although we assume a good working knowledge of Haskell This paper is dedicated in memory of Edsger W Dijkstra for his influential insight that mathematical logic is and must be the basis for sensible computer program construction

/pdf/arrows-robots-and-functional-reactive-programming-rzvmbmnjze.pdf

Arrows, Robots, and Functional Reactive Programming

Lazy functional languages are declarative and allow the programmer to write programs where operational issues such as the evaluation order are left implicit. It is desirable to maintain a declarative view also during debugging so as to avoid burdening the programmer with operational details, for example concerning the actual evaluation order which tends to be difficult to follow. Conventional debugging techniques focus on the operational behaviour of a program and thus do not constitute a suitable foundation for a general-purpose debugger for lazy functional languages. Yet, the only readily available, general-purpose debugging tools for this class of languages are simple, operational tracers.This thesis presents a technique for debugging lazy functional programs declaratively and an efficient implementation of a declarative debugger for a large subset of Haskell. As far as we know, this is the first implementation of such a debugger which is sufficiently efficient to be useful in practice. Our approach is to construct a declarative trace which hides the operational details, and then use this as the input to a declarative (in our case algorithmic) debugger.The main contributions of this thesis are:A basis for declarative debugging of lazy functional programs is developed in the form of a trace which hides operational details. We call this kind of trace the Evaluation Dependence Tree (EDT).We show how to construct EDTs efficiently in the context of implementations of lazy functional languages based on graph reduction. Our implementation shows that the time penalty for tracing is modest, and that the space cost can be kept below a user definable limit by storing one portion of the EDT at a time.Techniques for reducing the size of the EDT are developed based on declaring modules to be trusted and designating certain functions as starting-points for tracing.We show how to support source-level debugging within our framework. A large subset of Haskell is handled, including list comprehensions.Language implementations are discussed from a debugging perspective, in particular what kind of support a debugger needs from the compiler and the run-time system.We present a working reference implementation consisting of a compiler for a large subset of Haskell and an algorithmic debugger. The compiler generates fairly good code, also when a program is compiled for debugging, and the resource consumption during debugging is modest. The system thus demonstrates the feasibility of our approach.

Declarative debugging for lazy functional languages

Laser Doppler flowmetry (LDF) is a non invasive method enabling the monitoring of microvascular blood flow, a very important marker of tissue health. This article gives an overview on the concept of LDF for microvascular perfusion monitoring and imaging. It first describes the theoretical background of the technique. Then, the benefits of LDF signal processing are shown through clinical examples: use of time–frequency representations and wavelets. Afterwards, the paper introduces novel approaches of velocity components. For that purpose, a work providing the determination of the velocities relative contribution in physiologically relevant units (mm/s) is presented. Imaging perfusion is also reviewed through methods based on laser speckle. The most prominent disadvantage of the latter devices being the time needed to produce a perfusion image, solutions are proposed in the last part of the paper.

Laser Doppler perfusion monitoring and imaging: novel approaches.

Simulated worlds are a common (and highly lucrative) application domain that stretches from detailed simulation of physical systems to elaborate video game fantasies. We believe that Functional Reactive Programming (FRP) provides just the right level of functionality to develop simulated worlds in a concise, clear and modular way. We demonstrate the use of FRP in this domain by presenting an implementation of the classic "Space Invaders" game in Yampa, our most recent Haskell-embedded incarnation of FRP.

Henrik Nilsson

Papers

Functional reactive programming, continued

Arrows, Robots, and Functional Reactive Programming

Declarative debugging for lazy functional languages

Laser Doppler perfusion monitoring and imaging: novel approaches.

The Yampa arcade