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A companion to the bestseller, The Impact of Economic Policies on Poverty and Income Distribution, this title deals with theoretical challenges and cutting-edge macro-micro linkage models. The authors compare the predictive and analytical power of various macro-micro linkage techniques using the traditional RHG approach as a benchmark to evaluate standard policies, such as, a typical stabilization package and a typical structural reform policy.

Conventional tensile testing applied to high density polyethylene can lead to erroneous impressions of the tensile response of the material due to a local reduction in cross section of the sample. Several workers have developed novel tensile testing techniques to measure the response of a small element as it deforms. The true stress true strain curve that results describes tensile deformation of the material in a geometry‐independent manner. Here, results from previous workers, together with some of our own, are interpreted in terms of the Haward‐Thackray spring‐dashpot model, in which the spring defines a strain hardening process according to the theories of high elasticity and the dashpot describes a strain‐independent viscous process. The effects that temperature, strain rate, and molecular mass have on each process are investigated. For a pipe‐grade, modified high density ethylene copolymer, sufficient data have been measured to interpret the effects of strain rate and temperature in accordance with an Eyring flow process, where the parameters for the two mechanisms are found to be similar.

This book reviews quantitative methods and models of impact evaluation. The formal literature on impact evaluation methods and practices is large, with a few useful overviews. Yet there is a need to put the theory into practice in a hands-on fashion for practitioners. This book also details challenges and goals in other realms of evaluation, including monitoring and evaluation (M&E), operational evaluation, and mixed-methods approaches combining quantitative and qualitative analyses. This book is organized as follows. Chapter two reviews the basic issues pertaining to an evaluation of an intervention to reach certain targets and goals. It distinguishes impact evaluation from related concepts such as M&E, operational evaluation, qualitative versus quantitative evaluation, and ex-ante versus ex post impact evaluation. Chapter three focuses on the experimental design of an impact evaluation, discussing its strengths and shortcomings. Various non-experimental methods exist as well, each of which are discussed in turn through chapters four to seven. Chapter four examines matching methods, including the propensity score matching technique. Chapter five deal with double-difference methods in the context of panel data, which relax some of the assumptions on the potential sources of selection bias. Chapter six reviews the instrumental variable method, which further relaxes assumptions on self-selection. Chapter seven examines regression discontinuity and pipeline methods, which exploit the design of the program itself as potential sources of identification of program impacts. Specifically, chapter eight presents a discussion of how distributional impacts of programs can be measured, including new techniques related to quantile regression. Chapter nine discusses structural approaches to program evaluation, including economic models that can lay the groundwork for estimating direct and indirect effects of a program. Finally, chapter ten discusses the strengths and weaknesses of experimental and non-experimental methods and also highlights the usefulness of impact evaluation tools in policy making.

Long description: Der Umgang mit Fremden ist ein zentrales Thema in unserer Gesellschaft, da im Zuge der Globalisierung und Internationalisierung Kontakte mit fremden Kulturen auf der Tagesordnung stehen. Um eine gewisse interkulturelle Kompetenz zu gewährleisten, d.h. mit Menschen anderer Kulturkreise erfolgreich interagieren zu können, aber auch fremdenfeindliche Einstellungen zu reduzieren, ist ein entsprechender Unterricht vonnöten. In dieser Arbeit wurden Werkzeuge und Methoden zur Erfassung grundlegender Einstellungen und fremdenfeindlicher Kognitionen sowie Stereotypen entwickelt. Auf Basis eines multimethodalen Ansatzes wurde ein Evaluationskonzept geschaffen, das die Effektivität von Unterricht zum Abbau von Fremdenfeindlichkeit auf impliziter und expliziter Ebene nachweisen kann.

The Brinell, Vickers, Meyer, Rockwell, Shore, IHRD, Knoop, Buchholz, and nanoindentation methods used to measure the indentation hardness of materials at different scales are compared, and main issues and misconceptions in the understanding of these methods are comprehensively reviewed and discussed. Basic equations and parameters employed to calculate hardness are clearly explained, and the different international standards for each method are summarized. The limits for each scale are explored, and the different forms to calculate hardness in each method are compared and established. The influence of elasticity and plasticity of the material in each measurement method is reviewed, and the impact of the surface deformation around the indenter on hardness values is examined. The difficulties for practical conversions of hardness values measured by different methods are explained. Finally, main issues in the hardness interpretation at different scales are carefully discussed, like the influence of grain size in polycrystalline materials, indentation size effects at micro- and nanoscale, and the effect of the substrate when calculating thin films hardness. The paper improves the understanding of what hardness means and what hardness measurements imply at different scales.

The cyclotron frequency of a charged particle in a uniform magnetic field B is related to its mass m and charge q by the relationship ω c = qB / m . This simple relationship forms the basis for sensitive mass comparisons using ion cyclotron resonance mass spectroscopy, with applications ranging from the identification of biomolecules 1 and the study of chemical reaction rates 2 to determinations of the fine structure constant of atomic spectra 3 . Here we report the observation of a deviation from the cyclotron frequency relationship for polarizable particles: in high-accuracy measurements of a single CO + ion, a dipole induced in the orbiting ion shifts the measured cyclotron frequency. We use this cyclotron frequency shift to measure non-destructively the quantum state of the CO + ion. The effect also provides a means to determine to a few per cent the body-frame dipole moment of CO + , thus establishing a method for measuring dipole moments of molecular ions for which few comparably accurate measurements exist 4 , 5 , 6 . The general perturbation that we describe here affects the most precise mass comparisons attainable today 7 , 8 , with applications including direct tests of Einstein's mass–energy relationship 9 and charge-parity-time reversal symmetry 10 , and possibly the weighing of chemical bonds 7 .

Eine Verbesserung der heute bekannten Modelle und Messmethoden durch die Erfassung des rheologischen und thermophysikalischen Verhaltens der eingesetzten Betriebsstoffe ist notwendig, um einen Beitrag zur Reibungsminimierung wichtiger Antriebskomponenten zu erreichen. Hierbei spielt die Erhöhung des mechanischen Wirkungsgrads durch Reibungsreduzierung in fluidgeschmierten Kontakten eine wesentliche Rolle. In den tribologischen Kontakten treten Drücke auf, bei denen nicht-Newton'sches Verhalten und Viskoelastizität des Schmierstoffes immer wichtiger werden, da erhöhte Tangentialkräfte und Reibungsschubspannungen auftreten. Die Abhängigkeit der thermophysikalischen Eigenschaften von Schmierstoffen hängen in starkem Maße von der chemischen Zusammensetzung und der molekularen Struktur ab und dürfen nicht mehr vernachlässigt werden. Heute eingesetzte numerische Berechnungsprogramme nutzen Annahmen zum rheologischen Verhalten des Schmierstoffes, deren Gültigkeit in Frage zu stellen ist. Die Kenntnis der Wirkmechanismen des Fluiden unter tribologischer Beanspruchung ermöglicht eine direkte Einbindung in den Konstruktionsprozess für die Antriebskomponenten. Dabei ist es für die Reibung in geschmierten tribologischen Systemen entscheidend, wie viel Schubspannung ein Fluid durch Scherung überträgt.

With the development of error compensation technology, reliability and stability of error identification deserve much attention. And rotary axis errors of five-axis machine tool are the main error sources which result in machining inaccuracy. Hence, a new method for position-dependent geometric error (PDGE) identification of a rotary table using double ball bar was proposed in this paper. Especially, only the targeted rotary table was driven during the ball bar test, which can reduce the impact of interference error sources. During the measurement, the ball on the spindle holds still, and the ball on the rotary table rotates around the rotation axis. There are three mounting positions of magnetic socket on the rotary table. Total six measurement procedures of cone test are executed to obtain enough measuring results by setting different positions of magnetic socket ball. These measuring results are used to construct the identification model based on homogeneous transformation matrix (HTM). The impact of installation errors of the double ball bar on identified results was analyzed. The uncertainty of identified errors could be reduced with the single-axis driven and the installation parameter optimization. At last, testing experiments on a five-axis machine tool were conducted to verify the proposed method. The results confirm that the method is an effective way to identify PDGEs of a rotary axis, and the accuracy of identified results is improved.