Building an Academic Cloud for 500,000 Users

Under the brand name “sciebo – the Campuscloud” (derived from “science box”) a consortium of more than 20 research and applied science universities started a large scale cloud service for about 500,000 students and researchers in North Rhine-Westphalia, Germany’s most populous state. Starting with the much anticipated data privacy compliant sync & share functionality, sciebo offers the potential to become a more general cloud platform for collaboration and research data management which will be actively pursued in upcoming scientific and infrastructural projects. This project report describes the formation of the venture, its targets and the technical and the legal solution as well as the current status and the next steps.

Performance Analysis and Comparison between Legacy-PSM and U-APSD

This paper evaluates the performance of the most popular power saving mechanisms defined in the IEEE 802.11 standard, namely the Power Save Mode (Legacy-PSM) and the Unscheduled Automatic Power Save Delivery (U-APSD). The assessment comprises a detailed study concerning energy efficiency and capability to guarantee the required Quality of Service (QoS) for a certain application. The results, obtained in the OMNeT++ simulator, showed that U-APSD is more energy efficient than Legacy-PSM without compromising the end-to- end delay. Both U-APSD and Legacy-PSM revealed capability to guarantee the application QoS requirements in all the studied scenarios. However, unlike U-APSD, when Legacy-PSM is used in the presence of QoS demanding applications, all the stations connected to the network through the same access point will consume noticeable additional energy.

Real-World Evaluation of Sensor Context-aware Adaptive Duty-cycled Opportunistic Routing

Energy is of primary concern in wireless sensor networks (WSNs). Low power transmission makes the wireless links unreliable, which leads to frequent topology changes. Resulting packet retransmissions aggravate the energy consumption. Beaconless routing approaches, such as opportunistic routing (OR) choose packet forwarders after data transmissions, and are promising to support dynamic features of WSNs. This paper proposes SCAD - Sensor Context-aware Adaptive Duty-cycled beaconless OR for WSNs. SCAD is a cross-layer routing solution and it brings the concept of beaconless OR into WSNs. SCAD selects packet forwarders based on multiple types of network contexts. To achieve a balance between performance and energy efficiency, SCAD adapts duty-cycles of sensors based on real-time traffic loads and energy drain rates. We implemented SCAD in TinyOS running on top of Tmote Sky sensor motes. Real-world evaluations show that SCAD outperforms other protocols in terms of both throughput and network lifetime.

Next-to-Minimal SOFTSUSY

We describe an extension to the SOFTSUSY program that provides for the calculation of the sparticle spectrum in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), where a chiral superfield that is a singlet of the Standard Model gauge group is added to the Minimal Supersymmetric Standard Model (MSSM) fields. Often, a Z3 symmetry is imposed upon the model. SOFTSUSY can calculate the spectrum in this case as well as the case where general Z3 violating (denoted as ) terms are added to the soft supersymmetry breaking terms and the superpotential. The user provides a theoretical boundary condition for the couplings and mass terms of the singlet. Radiative electroweak symmetry breaking data along with electroweak and CKM matrix data are used as weak-scale boundary conditions. The renormalisation group equations are solved numerically between the weak scale and a high energy scale using a nested iterative algorithm. This paper serves as a manual to the NMSSM mode of the program, detailing the approximations and conventions used.

Social networks, mobility, and exchange systems during the Neolithic and Bronze Age of the Swiss Plateau

Excavations of Neolithic (4000 – 3500 BC) and Late Bronze Age (1200 – 800 BC) wetland sites on the northern Alpine periphery have produced astonishing and detailed information about the life and human environment of prehistoric societies. It is even possible to reconstruct settlement histories and settlement dynamics, which suggest a high degree of mobility during the Neolithic. Archaeological finds—such as pottery—show local typological developments in addition to foreign influences. Furthermore, exogenous lithic forms indicate far reaching interaction. Many hundreds of bronze artefacts are recorded from the Late Bronze Age settlements, demonstrating that some wetland sites were centres of bronzework production. Exogenous forms of bronzework are relatively rare in the wetland settlements during the Late Bronze Age. However, the products produced in the lake-settlements can be found widely across central Europe, indicating their continued involvement in interregional exchange partnerships. Potential motivations and dynamics of the relationships between sites and other regions of Europe will be detailed using case studies focussing on the settlements Seedorf Lobsigensee (BE), Concise (VD), and Sutz-Lattrigen Hauptstation innen (BE), and an initial assessment of intra-site connectivity through Network Analysis of sites within the region of Lake Neuchâtel, Lake Biel, and Lake Murten.

Relating one's social support network to one's mid term grade

Much has been written about the relation of social support to health outcomes. Support networks were found to be predictive of health status. Not so clear was the manner in which social support helped the individual to avoid health complications. Whereas some aspects of the support network were protective, others were burdensome. Duties to one's network could serve as a stressor and duties outside one's network might stress the support system itself. Exposure to one's network was associated with certain health risks while disruption in one's social support network was associated with other health risks.^ Many factors contributed to the impact of a social support network upon the individual member: the characteristics of the individual, the individual's role or position within the network, qualities of the network and duties or indebtedness of the individual to the network. This investigation considered the possibility that performance could serve as a stressor in a fashion similar to an exposure to a health hazard.^ Because the literature includes many examples of studies in which the subjects were college students, academic progress is a performance common to most subjects. A profile of the support networks of successful students was contrasted with those of less successful students in this correlational study.^ What was uncovered in this investigation was a very complex web of interrelated constructs. Most aspects of the social support network did not significantly predict academic performance. Only a limited number of characteristics were associated with academic success: the frequency of support, student age, the existence of a 'mentor' within one' s network, and the extent to which one received a predominant source of support. Other factors had a tendency to be negatively correlated with midterm grade, suggesting those factors may impede academic performance.^ Medical status did not predict grades, but was correlated with many aspects of the network. Disruptions in particular parts of one's network were correlated with particular health categories. In fact, disruption in social support was more predictive of academic outcomes than medical complications. Whereas the individual's values were related to the contributing factors, only the individual's satisfaction with certain aspects of the support network were predictive of higher midterm grades in a psychology class. Dissatisfaction was associated with lower grades, suggesting a disruptive effect within the network. Associations among the features of support networks which predicted academic progress were considered. ^

Source data for Plos ONE publication Redefining thermal regimes to design reserves for coral reefs in the face of climate change

Reef managers cannot fight global warming through mitigation at local scale, but they can use information on thermal patterns to plan for reserve networks that maximize the probability of persistence of their reef system. Here we assess previous methods for the design of reserves for climate change and present a new approach to prioritize areas for conservation that leverages the most desirable properties of previous approaches. The new method moves the science of reserve design for climate change a step forwards by: (1) recognizing the role of seasonal acclimation in increasing the limits of environmental tolerance of corals and ameliorating the bleaching response; (2) including information from several bleaching events, which frequency is likely to increase in the future; (3) assessing relevant variability at country scales, where most management plans are carried out. We demonstrate the method in Honduras, where a reassessment of the marine spatial plan is in progress.

Financial permeation as a role of microfinance : has microfinance actually been helpful to the poor?

This article is distinct in its application of the logit transformation to the poverty ratio for the purpose of empirically examining whether the financial sector helps improve standards of living for low-income people. We propose the term financial permeation to describe how financial networks expand to spread money among the poor. We measure financial permeation by three indicators related to microfinance institutions (MFIs) and then examine its effect on poverty reduction at the macro level using panel data for 90 developing countries from 1995 to 2008. We find that financial permeation has a statistically significant and robust effect on decreasing the poverty ratio.

Development of Efficient Techniques for the Analysis and Design of Antennas in Dual-Reflectarray Configuration

This thesis contributes to the analysis and design of printed reflectarray antennas. The main part of the work is focused on the analysis of dual offset antennas comprising two reflectarray surfaces, one of them acts as sub-reflector and the second one acts as mainreflector. These configurations introduce additional complexity in several aspects respect to conventional dual offset reflectors, however they present a lot of degrees of freedom that can be used to improve the electrical performance of the antenna. The thesis is organized in four parts: the development of an analysis technique for dualreflectarray antennas, a preliminary validation of such methodology using equivalent reflector systems as reference antennas, a more rigorous validation of the software tool by manufacturing and testing a dual-reflectarray antenna demonstrator and the practical design of dual-reflectarray systems for some applications that show the potential of these kind of configurations to scan the beam and to generate contoured beams. In the first part, a general tool has been implemented to analyze high gain antennas which are constructed of two flat reflectarray structures. The classic reflectarray analysis based on MoM under local periodicity assumption is used for both sub and main reflectarrays, taking into account the incident angle on each reflectarray element. The incident field on the main reflectarray is computed taking into account the field radiated by all the elements on the sub-reflectarray.. Two approaches have been developed, one which employs a simple approximation to reduce the computer run time, and the other which does not, but offers in many cases, improved accuracy. The approximation is based on computing the reflected field on each element on the main reflectarray only once for all the fields radiated by the sub-reflectarray elements, assuming that the response will be the same because the only difference is a small variation on the angle of incidence. This approximation is very accurate when the reflectarray elements on the main reflectarray show a relatively small sensitivity to the angle of incidence. An extension of the analysis technique has been implemented to study dual-reflectarray antennas comprising a main reflectarray printed on a parabolic surface, or in general in a curved surface. In many applications of dual-reflectarray configurations, the reflectarray elements are in the near field of the feed-horn. To consider the near field radiated by the horn, the incident field on each reflectarray element is computed using a spherical mode expansion. In this region, the angles of incidence are moderately wide, and they are considered in the analysis of the reflectarray to better calculate the actual incident field on the sub-reflectarray elements. This technique increases the accuracy for the prediction of co- and cross-polar patterns and antenna gain respect to the case of using ideal feed models. In the second part, as a preliminary validation, the proposed analysis method has been used to design a dual-reflectarray antenna that emulates previous dual-reflector antennas in Ku and W-bands including a reflectarray as subreflector. The results for the dualreflectarray antenna compare very well with those of the parabolic reflector and reflectarray subreflector; radiation patterns, antenna gain and efficiency are practically the same when the main parabolic reflector is substituted by a flat reflectarray. The results show that the gain is only reduced by a few tenths of a dB as a result of the ohmic losses in the reflectarray. The phase adjustment on two surfaces provided by the dual-reflectarray configuration can be used to improve the antenna performance in some applications requiring multiple beams, beam scanning or shaped beams. Third, a very challenging dual-reflectarray antenna demonstrator has been designed, manufactured and tested for a more rigorous validation of the analysis technique presented. The proposed antenna configuration has the feed, the sub-reflectarray and the main-reflectarray in the near field one to each other, so that the conventional far field approximations are not suitable for the analysis of such antenna. This geometry is used as benchmarking for the proposed analysis tool in very stringent conditions. Some aspects of the proposed analysis technique that allow improving the accuracy of the analysis are also discussed. These improvements include a novel method to reduce the inherent cross polarization which is introduced mainly from grounded patch arrays. It has been checked that cross polarization in offset reflectarrays can be significantly reduced by properly adjusting the patch dimensions in the reflectarray in order to produce an overall cancellation of the cross-polarization. The dimensions of the patches are adjusted in order not only to provide the required phase-distribution to shape the beam, but also to exploit the crosses by zero of the cross-polarization components. The last part of the thesis deals with direct applications of the technique described. The technique presented is directly applicable to the design of contoured beam antennas for DBS applications, where the requirements of cross-polarisation are very stringent. The beam shaping is achieved by synthesithing the phase distribution on the main reflectarray while the sub-reflectarray emulates an equivalent hyperbolic subreflector. Dual-reflectarray antennas present also the ability to scan the beam over small angles about boresight. Two possible architectures for a Ku-band antenna are also described based on a dual planar reflectarray configuration that provides electronic beam scanning in a limited angular range. In the first architecture, the beam scanning is achieved by introducing a phase-control in the elements of the sub-reflectarray and the mainreflectarray is passive. A second alternative is also studied, in which the beam scanning is produced using 1-bit control on the main reflectarray, while a passive subreflectarray is designed to provide a large focal distance within a compact configuration. The system aims to develop a solution for bi-directional satellite links for emergency communications. In both proposed architectures, the objective is to provide a compact optics and simplicity to be folded and deployed.

Qualitative Monitoring of Video Quality of Experience

Real-time monitoring of multimedia Quality of Experience is a critical task for the providers of multimedia delivery services: from television broadcasters to IP content delivery networks or IPTV. For such scenarios, meaningful metrics are required which can generate useful information to the service providers that overcome the limitations of pure Quality of Service monitoring probes. However, most of objective multimedia quality estimators, aimed at modeling the Mean Opinion Score, are difficult to apply to massive quality monitoring. Thus we propose a lightweight and scalable monitoring architecture called Qualitative Experience Monitoring (QuEM), based on detecting identifiable impairment events such as the ones reported by the customers of those services. We also carried out a subjective assessment test to validate the approach and calibrate the metrics. Preliminary results of this test set support our approach.

Reduced synchronization persistence in neural networks derived from atm-deficient mice

Many neurodegenerative diseases are characterized by malfunction of the DNA damage response. Therefore, it is important to understand the connection between system level neural network behavior and DNA. Neural networks drawn from genetically engineered animals, interfaced with micro-electrode arrays allowed us to unveil connections between networks’ system level activity properties and such genome instability. We discovered that Atm protein deficiency, which in humans leads to progressive motor impairment, leads to a reduced synchronization persistence compared to wild type synchronization, after chemically imposed DNA damage. Not only do these results suggest a role for DNA stability in neural network activity, they also establish an experimental paradigm for empirically determining the role a gene plays on the behavior of a neural network.

Software para análisis automático de ficheros de imagen

El presente proyecto fin de carrera consiste en el diseño, desarrollo e implementación de una aplicación informática cuya función sea la identificación de distintos ficheros de imagen, audio y video y la interpretación y presentación de los metadatos asociados a los mismos. El software desarrollado, EXTRACTORDATOS_LBS, reconocerá el tipo de formato del fichero bajo estudio a partir del análisis de los bytes de identificación contenidos en la cabecera del archivo. En base a la información registrada en dicha cabecera, la aplicación interpretará el contenido de los metadatos asociados al fichero, mostrando por pantalla aquellos que resulten de interés para el análisis de los mismos. Previamente a la implementación del software se acomete el análisis teórico de los formatos de diversos archivos multimedia, recogidos en múltiples normas y recomendaciones. Tras esa identificación, se procede al desarrollo de la aplicación EXTRACTORDATOS_LBS , que informa de los parámetros de interés contenidos en las cabeceras de los archivos. El desarrollo se ilustra con los diagramas conceptuales asociados a la arquitectura del software implementado. De igual forma, se muestran las salidas por pantalla de una serie de ficheros de muestra, y se presenta el manual de usuario de la aplicación. La versión electrónica de este documento acompaña el ejecutable que permite el análisis de los archivos. This final project consists in the design, development and implementation of a computer application whose function is the identification of different image, audio and video files and the interpretation and presentation of their metadata. The software developed, EXTRACTORDATOS_LBS, will recognize the type of the file under study through the analysis of the identification bytes contained on the file’s header. Based on information registered in this header, the application will interpret the metadata content associated to file, displaying the most interesting ones for their analysis. Prior to the software implementation, a theoretical analysis of the different formats of media files is undertaken. After this identification, the application EXTRACTORDATOS_LBS is developed. This software analyzes and displays the most interesting parameters contained in multimedia file’s header. The development of the application is illustrated with flow charts associated to the architecture of the software. Furthermore, some graphic examples of use of the program are included, as well as the user’s manual. The electronic version of this document attaches the executable file that permits file analysis.

A computer program for the analysis of the dynamic bending-torsion coupling in bridges using a mini-computer

The analysis of modes and natural frequencies is of primary interest in the computation of the response of bridges. In this article the transfer matrix method is applied to this problem to provide a computer code to calculate the natural frequencies and modes of bridge-like structures. The Fortran computer code is suitable for running on small computers and results are presented for a railway bridge.

Aportaciones del Proyecto Votescript a los Esquemas Tradicionales de Voto Electrónico.

This paper hallmarks the most relevant contributions carried out by the authors in the VOTESCRIPT project (TIC2000-1630-C02). The main goal of this project was the analysis, definition and implementation of a system which copes with every phases and elements existing in a process of electronic voting using computer networks. A summary of the main criticisms of electronic voting is presented to disclose that the most relevant voting schemes only take into account a technological perspective, just trying to imitate the conventional voting schemes. Nevertheless in these proposals important aspects such individual and global verification are not properly undertaken. The paper includes the proposed solutions of the project to solve these mentioned problems.

Del voto electrónico al voto telemático

Este artículo presenta los aspectos más relevantes del trabajo realizado por los autores dentro del proyecto VOTESCRIPT (TIC2000-1630-C02). El objetivo principal de este proyecto fue el análisis, definición e implementación de un sistema que abarcara todas las fases y elementos existentes en un proceso de votación electrónica sobre redes de ordenadores. El artículo incluye las soluciones propuestas dentro del proyecto. This paper hallmarks the most relevant contributions carried out by the authors in the VOTESCRIPT project (TIC2000-1630-C02). The main goal of this project was the analysis, definition and implementation of a system, which copes with every phases and elements existing in a process of electronic voting using computer networks. The paper includes the proposed solutions of the project to solve these problems.