Azimuthal asymmetries for hadron distributions inside jets in hadronic collisions

Using a generalized parton model approach including spin and intrinsic parton motion effects, and assuming the validity of factorization for large p_T jet production in hadronic collisions, we study the azimuthal distribution around the jet axis of leading pions, produced in the jet fragmentation process. We identify the observable leading-twist azimuthal asymmetries for the unpolarized and single-polarized case related to both quark and gluon-originated jets. We account for all physically allowed combinations of the transverse momentum dependent (TMD) parton distribution and fragmentation functions, with special attention to the Sivers, Boer-Mulders, and transversity quark distributions, and to the Collins fragmentation function for quarks (and to the analogous functions for gluon partons).Comment: 8 pages, 5 figures, to appear in the proceedings of 19th International Spin Physics Symposium (SPIN2010), Sep 27-Oct 2, 2010, Juelich (Germany

Null Polygonal Wilson Loops in Full N=4 Superspace

We compute the one-loop expectation value of light-like polygonal Wilson loops in N=4 super-Yang-Mills theory in full superspace. When projecting to chiral superspace we recover the known results for tree-level next-to-maximally-helicity-violating (NMHV) scattering amplitude. The one-loop MHV amplitude is also included in our result but there are additional terms which do not immediately correspond to scattering amplitudes. We finally discuss different regularizations and their Yangian anomalies.Comment: 55 pages, v2: reference adde

Accessing the distribution of linearly polarized gluons in unpolarized hadrons

Gluons inside unpolarized hadrons can be linearly polarized provided they have a nonzero transverse momentum. The simplest and theoretically safest way to probe this distribution of linearly polarized gluons is through cos(2 phi) asymmetries in heavy quark pair or dijet production in electron-hadron collisions. Future Electron-Ion Collider (EIC) or Large Hadron electron Collider (LHeC) experiments are ideally suited for this purpose. Here we estimate the maximum asymmetries for EIC kinematics.Comment: 4 pages, 2 figures, to appear in the proceedings of the XIX International Workshop on Deep Inelastic Scattering and Related Subjects (DIS 2011), Newport News, VA, USA, 11-15 April 201

Importance of Elastic Recovery in the DSR for Binders and Mastics

Elastic Recovery (ER) is used by many highway agencies for modified bitumen grading specifications. The current ASTM/AASHTO standards for ER testing utilize the ductility bath as the measurement apparatus. A new procedure for measuring the elastic recovery in the Dynamic Shear Rheometer (ER-DSR) was developed and was used to test different polymer modified binders and mastics. The results show a good correlation between the ER-DSR and ER measured in the ductility bath (ER-DB). The ER-DSR requires less material and is more time efficient and repeatable than the ER-DB. Since the link between the ER measurements and pavement performance is not well established, the study compared ER measurements with binder rutting and fatigue results as measured by the Multiple Stress Creep and Recovery (MSCR) test and the linear amplitude sweep (LAS) test, respectively. Generally, binders and mastics with higher ER-DSR value showed higher percent recovery (MSCR) and fatigue resistance (LAS). This study also showed the effect of natural and manufactured fillers on the percent recovery measured with the MSCR test. Based on the experimental results, it is recommended to replace ER-DB with the ER-DSR. Also, agencies should consider the MSCR and fatigue tests as indicators of binder modification rather than the ER, as they provide direct measurements of damage resistance characteristics for which the elastic recovery might not indicate

Diseño de un sistema de gestión en control operacional y su aplicación en una fabrica productora de harina y aceite de pescado.

This thesis is about the design of a management system in operational control and its application in a factory that produces flour and oil fish based on the British Norma Pass 55 and having as a foundation the basis of TPM and the philosophy of the 5S´s. This work emerges from the necessity of the company, in the searching of improving the management of its process in order to guarantee that all resources produce the expected quality margin of service inside the appropriate economical frame. To do so, a study of the administrative, human and technical factors was made in order to establish the parameters, processes and required aspects to design the management system in operational control. A computing application will standardize this information. The design of this system allowed an increasing result in the capacity of fishing collecting of a 20% having the same cost that it has now. At the same time the stop time of the equipment was reduced and as a result an increase of a 25 % was gotten in the level of the performance of the capture of the fish flour

Numerical simulations of aggregate breakup in bounded and unbounded turbulent flows

Breakup of small aggregates in fully developed turbulence is studied by means of direct numerical simulations in a series of typical bounded and unbounded flow configurations, such as a turbulent channel flow, a developing boundary layer and homogeneous isotropic turbulence. The simplest criterion for breakup is adopted, whereas aggregate breakup occurs when the local hydrodynamic stress $\sigma\sim \varepsilon^{1/2}$, with $\varepsilon$ being the energy dissipation at the position of the aggregate, overcomes a given threshold $\sigma_\mathrm{cr}$, which is characteristic for a given type of aggregates. Results show that the breakup rate decreases with increasing threshold. For small thresholds, it develops a universal scaling among the different flows. For high thresholds, the breakup rates show strong differences between the different flow configurations, highlighting the importance of non-universal mean-flow properties. To further assess the effects of flow inhomogeneity and turbulent fluctuations, theresults are compared with those obtained in a smooth stochastic flow. Furthermore, we discuss the limitations and applicability of a set of independent proxies.Comment: 15 pages, 12 figures, Refinded discussion in Section 2.1, results unchange

Reconstructing the Density of States by History-Dependent Metadynamics

We present a novel method for the calculation of the energy density of states D(E) for systems described by classical statistical mechanics. The method builds on an extension of a recently proposed strategy that allows the free energy profile of a canonical system to be recovered within a pre-assigned accuracy,[A. Laio and M. Parrinello, PNAS 2002]. The method allows a good control over the error on the recovered system entropy. This fact is exploited to obtain D(E) more efficiently by combining measurements at different temperatures. The accuracy and efficiency of the method are tested for the two-dimensional Ising model (up to size 50x50) by comparison with both exact results and previous studies. This method is a general one and should be applicable to more realistic model systems

A large-scale study on the security vulnerabilities of cloud deployments

As cloud deployments are becoming ubiquitous, the rapid adoption of this new paradigm may potentially bring additional cyber security issues. It is crucial that practitioners and researchers pose questions about the current state of cloud deployment security. By better understanding existing vulnerabilities, progress towards a more secure cloud can be accelerated. This is of paramount importance especially with more and more critical infrastructures moving to the cloud, where the consequences of a security incident can be significantly broader. This study presents a data-centric approach to security research – by using three static code analysis tools and scraping the internet for publicly available codebases, a footprint of the current state of open-source infrastructure-as-code repositories can be achieved. Out of the scraped 44485 repository links, the study is concentrated on 8256 repositories from the same cloud provider, across which 292538 security violations have been collected. Our contributions consist of: understanding on existing security vulnerabilities of cloud deployments, contributing a list of Top Guidelines for practitioners to follow to securely deploy systems in the cloud, and providing the raw data for further studies.info:eu-repo/semantics/acceptedVersio