New statistical distributions for group counting in?Bernoulli and Poisson processes

Based on a sequential group sampling procedure, the authors introduce a new statistical distribution for group-by-group counting for Bernoulli processes. Suppose that a population contains an infinite number of items, each item having probability p for nonconformity and probability 1−p for conformity. Items are inspected group by group, where each group contains m items, and the number of nonconforming items are recorded only when inspection of a group is completed. The inspection procedure is terminated if the cumulative number of nonconforming items recorded is greater than or equal to a specified number r. The distribution introduced in this paper consists of two random variables: the number of groups inspected, K, and the cumulative number of nonconforming items observed, X. Statistical properties and inferences for the bivariate distribution of (K,X) are studied. The authors also discuss the limiting case as m→∞ and p→0 with mp fixed, and derive a new bivariate distribution for group-by-group counting for Poisson processes that approaches the gamma distribution in limit. A new type of control chart and an acceptance sampling procedure are developed based on (K,X), and examples are given to illustrate their applications.     

Does intersectoral labour mobility pay for academics?

This contribution studies the technological capabilities of Central and Eastern European (CEE) economies based on priority filings for the period of 1980–2009. From a global perspective, the indicators suggest a division of labour in technological activities among world regions whereby Europe, Latin America and the former USSR are specializing in sectors losing technological dynamism (Chemicals and Mechanical Engineering) while North America, the Middle East (especially Israel) and Asia Pacific are increasingly specializing in Electrical Engineering, a sector with significant technological opportunities. Regarding priority filings, CEE reduced its technological activities drastically after 1990. The recovery of CEE economies regarding technological capabilities is unfolding very slowly. The results speak for the ability of CEE countries in contributing to a limited number of fields with growing technological opportunities. The technological profile of the CEE region will more likely than not complicate the technology upgrading process towards activities at the technological frontier.     

Are citation-based quantitative techniques adequate for measuring science on the periphery?

The inadequacies of citation analysis-based quatitative techniques in the context of developing countries owe their origins to the rather small size of most peripheral country scientific enterprises, the poor coverage of Third World journals in bibliographic databases, (and in particularSCI), the cognitive limitations of citation analysis pointed out by microsociologists, and the non-normative nature of the scientific enterprise in these countries. Much of peripheral science is derivative and imitative of science done in the centre, rather than original or path-breaking, and there is hardly any indigenous scientific community. And yet, citation analysis-based quantitative measures can be applied to characterise different aspects of peripheral science. These techniques assume great importance, especially in view of the massive inadequacies of the peer review process prevailing in these countries. The application of such citation-based quantification to units of different levels of aggregation such as a journal, an institution and a country as a whole has been demonstrated taking India as the example. Our results show that levels of funding have no correlation with the quality or international citation impact of the literature output resulting from a project. Almost all Indian journals have a very low impact on world literature, and the relatively better performance ofJournal of Astrophysics and Astronomy (and Indian astronomical research in general) owes it to favourable factors, both social and cognitive.     

Does motivation matter in evaluation of research institutions? Evidence from Polish public universities

The ongoing internationalisation of economies more and more intensely influences the activity of the education and science sector—consequently, the pressure to achieve the institutional and individual goals increases. Given these circumstances, the authors of this article decided to identify the relations between the type and scope of motivation used at universities and the evaluation results of their study and scientific activity. The study was carried out on Polish universities among a representative study sample of 1303 academics. For the analysis of the results, correlation analysis, regression models and data mining techniques were used. The research results indicated connections between the level of the study being carried out with such motivators as working in conditions of high innovativeness, wide access to publications and infrastructure, allowing for commercialisation of the study results. The increase in the quality level of the study is also fostered by the support and help of direct supervisors. What is demotivating is the periodic qualitative assessment and unproductive relations with the environment. The study results filled the gaps in the knowledge on the relations between the motivation and the evaluation of the university and between the range and type of motivators used in higher education.     

Does antisymmetry matter in b.c.c. 3He crystals?

By comparing the results of both variational and exact Diffusion Monte Carlo (DMC) results for states of different symmetries we conclude that antisymmetry plays a fundamental role in stabilizing the b.c.c. ³ He crystal. We performed calculations for a system of 54 particles of mass 3 at density = 0.02557 Å, just above the experimental freezing point. Symmetric (Jastrow and Shadow wave functions) and unsymmetrized wave functions (of the Nosanow-Jastrow type), fail to describe the system. In particular, a shadow wave function predicts a fluid as lowest energy state at the density considered, and this is confirmed by the computation of the exact symmetric ground state with DMC, which predicts an energy well below the experimental energy of the crystal. On the other hand, DMC calculations projecting the ground state in the space of the Nosanow–Jastrow functions, give an energy which is much above the experimental energy. The use of antisymmetric functions, and in particular of the recently introduced Fermionic Shadow Wave Function (FSWF), leads to the prediction that the b.c.c. crystal is the stable ground state. Antisymmetry plays therefore a fundamental role in this system. FSWF calculations also demonstrate the peculiar characteristics of this crystal (very low order parameter, a non Gaussian density profile around the lattice sites, and very wide vibrations of the atoms around the lattice sites, small dependence of the energy with respect to the magnetic order), which cannot be seen in the Nosanow framework.     

Brownian motion or Lévy walk? Stepping towards an extended statistical mechanics for animal locomotion

Animals moving under the influence of spatio-temporal scaling and long-term memory generate a kind of space-use pattern that has proved difficult to model within a coherent theoretical framework. An extended kind of statistical mechanics is needed, accounting for both the effects of spatial memory and scale-free space use, and put into a context of ecological conditions. Simulations illustrating the distinction between scale-specific and scale-free locomotion are presented. The results show how observational scale (time lag between relocations of an individual) may critically influence the interpretation of the underlying process. In this respect, a novel protocol is proposed as a method to distinguish between some main movement classes. For example, the ‘power law in disguise’ paradox—from a composite Brownian motion consisting of a superposition of independent movement processes at different scales—may be resolved by shifting the focus from pattern analysis at one particular temporal resolution towards a more process-oriented approach involving several scales of observation. A more explicit consideration of system complexity within a statistical mechanical framework, supplementing the more traditional mechanistic modelling approach, is advocated.     

Extrusion techniques on microstructure optimization and quantitative analysis of texture influence on ductility improvement for heat-resistant Mg–Nd–Zn–Zr magnesium alloy

Journal of Materials Science - Aiming at the ductility improvement of the rare-earth magnesium alloys, the influence of the microstructure refinement and texture on the strength and ductility was...     

Does the method for Military Utility Assessment of Future Technologies provide utility?

The Military Utility Assessment of Future Technologies (MUAFT) method was developed as a cost-efficient alternative to methods such as NATO's Disruptive Technology Assessment Games, to be used as a part of the Swedish Armed Forces' long-term capability development process. The question addressed in this study is whether MUAFT can be considered to have validity in its context and thus if it has potential to be useful to other small to medium size states. The analysis was based on an operationalization of Clark's framework for science and technology intelligence analysis, combined with a military capability centric view of military utility. MUAFT reports from 2012 to 2018 were reviewed in terms of how they satisfy five key criteria. The study shows that MUAFT provides utility, if used by a suitably composed group of experts, who are aware of the method's limitations. The limitations mainly originate from a lack of explicit support for assessing the impact of forces for change, other than technological forces, on military capability development. The expert group serves as the synthesizing bridge between technology forecasts and military utility assessments. Therefore, comprehensive expertise is needed in various military technology specialisations, in the sponsor's military capabilities and in subjects necessary to master in order to assess other influential societal forces for change.     

Comparison of reference image generation techniques for projection moiré interferometry

Three different approaches of generating reference images for projection moiré interferometry are compared. An interpolation-based phase-shift technique that phase shifts the actual reference images is shown to reduce error by over 25% and to reduce processing time compared with the common cosine-wave- and square-wave-based approaches.     

Does sustainable supplier co-operation affect performance? Examining implications for the triple bottom line

The increasing importance of sustainable behaviour in business has enhanced its impact on supply chain management. Firms foster sustainability in their supplier base in reaction to growing sustainability requirements in various ways, including sustainable supplier co-operation. Knowledge about the effects of sustainable supplier co-operation on firm performance is limited; therefore, this study tests antecedents and implications of sustainable supplier co-operation according to the triple bottom line. A survey of Western European firms reveals that sustainable supplier co-operation has generally positive effects on firm performance across social, green and economic dimensions. However, only green practices have positive significant effects on economic performance, not social practices (e.g., child labour rules). In contrast to practitioner perceptions, investments in sustainability, for example through sustainable supplier co-operation does indeed result in sufficient returns.     

Bimodal microstructure – A feasible strategy for high-strength and ductile metallic materials

Introducing a bimodal grain-size distribution has been demonstrated an efficient strategy for fabricating high-strength and ductile metallic materials, where fine grains provide strength, while coarse grains enable strain hardening and hence decent ductility. Over the last decades, research activities in this area have grown enormously, including interesting results on fcc Cu, Ni and Al-Mg alloys as well as steel and Fe alloys via various thermo-mechanical processing approaches. However, investigations on bimodal Mg and other hcp metals are relatively few. A brief overview of the available approaches based on thermo-mechanical processing technology in producing bimodal microstructure for various metallic materials is given, along with a summary of unusual mechanical properties achievable by bimodality, where focus is placed on the microstructure-mechanical properties and relevant mechanisms. In addition, key factors that influencing bimodal strategies, such as compositions of starting materials and processing parameters, together with the challenges this research area facing, are identified and discussed briefly.     

Does patient-centered care pay off?

BACKGROUND: Hospitals have adopted patient-centered practices that focus on patients' needs, values, and preferences in hopes of improving quality and controlling costs. Patient-centered practices are intended to involve patients in treatment decisions, increase communication between patients and care-givers, and increase interaction with family members and friends. Rapid adoption of these practices has occurred, even though little is known about the effects of patient-centered care on outcomes and cost. METHODS: A simultaneous equations regression model was developed to examine the reciprocal relationships between patient-centeredness, outcomes, and cost. A consortium of employers obtained data from 52 hospital units in southeastern Michigan. Two hundred randomly selected patients were sampled from all discharges on the medical, surgical, and obstetric units at each hospital for the first three months of 1997; the patients were sent the survey in May. Patient-centeredness was measured by patient reports of whether key clinical events occurred (The Picker Inpatient Survey). Outcomes were assessed by rates of unexpected mortality and complications. Cost was defined by self-insured purchaser payments. RESULTS: Hospital units that were more patient centered were associated with statistically significantly better outcomes and higher costs than those that were less patient centered. The joint relations between outcomes and cost were insignificant. CONCLUSIONS: Patient-centeredness was associated with better outcomes and higher cost. For either the short run or long run, managers, patients, and purchasers should determine whether the improvement in outcomes and patient satisfaction associated with becoming patient centered is worth the investment in costs.     

Does nanotech have a gender?

Gender is less of an issue in nanotechnology than in other areas of science and technology but, as Chris Toumey explains, public attitudes to nanotech do depend on gender.