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Inferring Temporal Behaviours Through Kernel Tracing
No full textIn order to provide reliable system support for real-time applications, it is often important to be able to collect statistics about the tasks temporal behaviours (in terms of execution times and inter-arrival times). Such statistics can, for example, be used to provide a-priori schedulability guarantees, or to perform some kind of on-line adaptation of the scheduling parameters (adaptive scheduling, or feedback scheduling). This work shows how the Linux kernel allows to collect such statistics by using an internal function tracer called Ftrace. Based on this feature, tools can be developed to evaluate the real-time performance of a system or an application, to debug real-time applications, and/or to infer the temporal properties (for example, periodicity) of tasks running in the system
Local z-functions, stress-energy tensor, field fluctuations, and all that, in curved static spacetime
No full textThis is a quick review on some technology concerning the local zeta function applied to Quantum Field Theory in curved static (thermal) spacetime to regularize the stress energy tensor and the field fluctuations
Job flows in Italian SMEs: a longitudinal analysis of growth, size and age
No full textThe paper proposes an empirical investigation of job flows for continuing manufacturing firms in Italy from 1996 to 2004 using high quality data on work forces and other characteristics of the firm. The magnitude of the job flows for small and medium-sized limited liability companies in Italy is lower than what observed in Anglo-Saxon countries, but it is still in line with evidence for firms in the Euro area. Second, the magnitude of job flows significantly shrunk in the aftermath of the economic downturn in 2001. Firms fared worse than in the late nineties and the labour market became less efficient in allocating job flows. Third, gross job creation and gross job destruction decrease as firm get larger, but when added to compute an indicator of net employment growth, size does not seem to affect firms’ expansion. On the contrary, age significantly hinges on the growth opportunities of small and medium-sized enterprises. The econometric analysis corroborates the major findings of our descriptive investigation referring to the role of size and age. In particular, it shows that classification methods used to define size classes strongly influence the estimated relationship between growth and size industrial regimes play a role in shaping job flows. Our result show that firms in supplier dominated industries fared significantly lower than enterprises in other sectors during the sample period
ADS-based Array Design for 2D and 3D Ultrasound Imaging
No full textThis paper describes a class of non-overlapping layouts based on almost difference sets (ADSs) for ultrasound applications. Thanks to the mathematical properties of ADSs, such arrays provide good radiation properties with far-field peak sidelobe levels belonging to an a priori predictable set of analytically-derived bounds. An extensive numerical analysis, including near-field simulations, is provided to assess the reliability and the features of the proposed design methodology for both linear and planar arrays. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works
Le citazioni degli inni prudenziani nelle 'Derivationes' di Osberno di Gloucester
No full textThe exam of the many quotations of Prudentius’ hymnical production in Osbernus of Gloucester’s Derivationes (half of the 12th century) points out that probably Osbernus quotes directly Prudentius, drawing on the branch B of his manuscripts tradition, and offers a substantially reliable text
La svolta sociologica nelle relazioni internazionali: tre approcci e tre filoni di ricerca
No full textThis paper aims to highlight some recent development in the field of International Relations. In the last twenty years there has been a change in the study of international politics, with a growing interest for theories and concepts from sociology. The first section analyzes the contribution of historical sociology to the study of international relations and, in particular, the research area of “domestic structure and foreign policy”. The second section presents the contribution of constructivism and the research area on “security cultures”. In the third section, sociological institutionalism and the research area of “learning and foreign policy” are illustrated. The final section discusses the linkage between these approaches
Concept Search: Semantics Enabled Information Retrieval
No full textIn this paper we present a novel approach, called Concept Search, which extends syntactic search, i.e., search based on the computation of string similarity between words, with semantic search, i.e., search based on the computation of semantic relations between concepts. The key idea of Concept Search is to operate on complex concepts and to maximally exploit the semantic information available, reducing to syntactic search only when necessary, i.e., when no semantic information is available. The experimental results show that Concept Search performs at least as well as syntactic search, improving the quality of results as a function of the amount of available semantics
Report on methods and algorithms for linking user-generated semantic annotations to Semantic Web and supporting their evolution in time
No full textThe INSEMTIVES project is concerned with increasing the amount of annotations available for various kinds of content, predominantly in a structured form using controlled vocabularies and aligned to content on the Semantic Web. In this deliverable we discuss solutions for generating links to external resources on the Semantic Web from structured annotations and how these annotations can evolve in time if controlled vocabularies, referred in these annotations, change. We discuss existing techniques for both problems and propose a set of methods (a) applicable to interlink various kinds of content and (b) to support the evolution of annotations in time
Discovering and Analyzing Scientific Communities using Conference Network
No full textThe increase number of scientific publications has made digital scientific literature search a difficult task and highly dependent of the researcher ability to search, filter and classify content. Most used scientific literature search engines and portals, such as Google Scholar, Citeseer and ACM, use only simple text-base and citation-base score to rank the query result, and the rank is barely useful. The number of references that a scientific publication has received (known as citations) determines the impact that the contribution has made to the community. Many methods (known as index) to measure or rank researchers are citation based. A fair index for these is important because it is used to evaluate and compare researchers for different purpose, such as university recruitment, faculty advancement, award of grants, among others. The world of science has many fields (Human, Social, Computer Science, etc.). Each field has different structures and publication dynamics. %\ale{Cite newman2001 and Structure and Dyna..}. An example is the number of citations in the top-20 most cited journals in Computer Science is 4 times higher than the top-20 most cited journals in Social Science. Therefore, it is unfair to compare researchers using citation-based metrics without a context, in other words, the community they belong to. Different sizes of communities make currently most used metrics that measure the productivity or impact of researchers an unfair evaluation when comparing researchers from different communities since those with higher productivity are likely to produce more citations than communities with lower productivity. This thesis presents a model and a tool for the detection and evaluation of scientific communities. Moreover, the detection of them will allow the improvement of two important activities in scientific research area: First, the of scientific contributions. Being aware of the existing relations between scientific entities by knowing the communities they are part of, will enable more efficient search mechanisms since the domain of the queries can be narrowed down to particular communities, or can be sparse to different communities to obtain diversity of content. Moreover, having a framework that supports discovering scientific communities will provide the means for a better understanding of the social behavior in the scope of scientific research, enabling us the possibility to identify patterns in developments of projects, research trends, successful research profiles, and so on. Second, the assessment of people (researchers). In InfEur2008 is suggested that numerical indicators must not be used to compare researches or researchers across different disciplines. Since nowadays the boarders between disciplines are blurring, it is hard to define a priori the disciplines to which someone belongs. Ad-hoc and evolving communities can provide a better way for this. The approach presented in this thesis combines different clustering algorithms for detecting overlapped scientific communities, based on conference publication data. The Community Engine Tool (CET) has implemented the algorithm and has been evaluated using the DBLP dataset, which contains information on more than 12 thousand conferences. The results showed that using our approach makes it possible to automatically produce community structure close to human-defined classification of conferences. The approach is part of a larger research effort aimed at studying how scientific communities are born, evolve, remain healthy or become unhealthy (e.g., self-referential), and eventually vanish
The Hodge decomposition theorem for general three-dimensional vector fields, without cuts
No full textPreprint. The Hodge decomposition of the space of square sommable vector fields defined on a domain of the ordinary three–dimensional space is a tool used in a wide theoretic and applied literature concerning Electromagnetism and Fluid dynamics. In order to obtain an effective Hodge decomposition, suitable also for numerical computations, the classical strategy, which goes back to Helmholtz and which is used nowadays as well, is to consider only bounded domains with sufficiently regular boundary, which contain connected and pairwise disjoint surfaces, called cut surfaces of , whose complement in is simply connected. The advantage of this situation is that the union of such cut surfaces does not have singularities, every curl–free vector field in admits potential in and hence it is possible to apply standard variational methods to obtain the Hodge decomposition via scalar potential formulations. Recently, R. Benedetti, R. Frigerio and the author gave an exhaustive topological description of bounded domains, called Helmholtz domains, which admit such cut surfaces. We proved that the Helmholtz domains are truly special three–dimensional domains. In fact, their topology is elementary. An evidence of this claim is given, for example, by the fact that the complement of any non-trivial thickened knot in a box domain is not a Helmholtz domain. In this way, we realize that the range of application of the classical strategy is quite limited. In this paper, we announce several results concerning an effective Hodge decomposition of valid for every bounded domain with Lipschitz–regular boundary, where describes a spatial medium formed by a possible inhomogeneous and/or anisotropic material