Corporatizing Open Source Software Innovation in the Plone Community

Increasingly open source (OS) software development is organized in a way similar to how a corporation would organize development. This paper examines this corporatizing effect by studying the relationship between peer-oriented social structures and goal-oriented technical structures in the Plone community. Social structures are said to exhibit assortative mixing, a like attract like characteristic whereas technical structures exhibits an opposite effect of disassortative mixing. Our first finding suggests that the patterns of collaborative contributions and interdependences among software modules exhibit the characteristic of disassortative mixing. Specifically, Plone developers were more likely to contribute to modules that already have a high concentration of contributions, which in turn lead to an increase in module reuse over time. This finding contributes to the debate of whether social systems are strictly assortative, and technological systems strictly disassortative (Newman, 2002). Our second contribution concerns the impact of corporatizing OSS projects, suggesting that corporatizing OS development had the effect of weakening the social organizing among developers, and shifted the patterns of contributions to adhere with the technical requirements

Quantifying Structural Attributes of System Decompositions in 28 Feature-oriented Software Product Lines: An Exploratory Study

Background: A key idea of feature orientation is to decompose a software product line along the features it provides. Feature decomposition is orthogonal to object-oriented decomposition it crosscuts the underlying package and class structure. It has been argued often that feature decomposition improves system structure (reduced coupling, increased cohesion). However, recent empirical findings suggest that this is not necessarily the case, which is the motivation for our empirical investigation. Aim: In fact, there is little empirical evidence on how the alternative decompositions of feature orientation and object orientation compare to each other in terms of their association with observable properties of system structure (coupling, cohesion). This motivated us to empirically investigate and compare the properties of three decompositions (object-oriented, feature-oriented, and their intersection) of 28 feature-oriented software product lines. Method: In an exploratory, observational study, we quantify internal attributes, such as import coupling and cohesion, to describe and analyze the different decompositions of a feature-oriented product line in a systematic, reproducible, and comparable manner. For this purpose, we use three established software measures (CBU, IUD, EUD) as well as standard distribution statistics (e.g., Gini coefficient). Results: First, feature decomposition is associated with higher levels of structural coupling in a product line than a decomposition into classes. Second, although coupling is concentrated in feature decompositions, there are not necessarily hot-spot features. Third, the cohesion of feature modules is not necessarily higher than class cohesion, whereas feature modules serve more dependencies internally than classes. Fourth, coupling and cohesion measurement show potential for sampling optimization in complex static and dynamic product-line analyses (product-line type checking, feature-interaction detection). Conclusions: Our empirical study raises critical questions about alleged advantages of feature decomposition. At the same time, we demonstrate how the measurement of structural attributes can facilitate static and dynamic analyses of software product lines. (authors' abstract)Series: Technical Reports / Institute for Information Systems and New Medi

Chaste: a test-driven approach to software development for biological modelling

Chaste (‘Cancer, heart and soft-tissue environment’) is a software library and a set of test suites for computational simulations in the domain of biology. Current functionality has arisen from modelling in the fields of cancer, cardiac physiology and soft-tissue mechanics. It is released under the LGPL 2.1 licence.\ud \ud Chaste has been developed using agile programming methods. The project began in 2005 when it was reasoned that the modelling of a variety of physiological phenomena required both a generic mathematical modelling framework, and a generic computational/simulation framework. The Chaste project evolved from the Integrative Biology (IB) e-Science Project, an inter-institutional project aimed at developing a suitable IT infrastructure to support physiome-level computational modelling, with a primary focus on cardiac and cancer modelling

Technical Design Report for the PANDA Micro Vertex Detector

This document illustrates the technical layout and the expected performance of the Micro Vertex Detector (MVD) of the PANDA experiment. The MVD will detect charged particles as close as possible to the interaction zone. Design criteria and the optimisation process as well as the technical solutions chosen are discussed and the results of this process are subjected to extensive Monte Carlo physics studies. The route towards realisation of the detector is outlined

Solid Oxide Fuel Cells Modeling Under Steady-State and Forced Oscillations Regimes

A mathematical model for the behavior of SOFCs has been developed using a commercial sofwtare, validated with experimental data and used to evaluate the effect of changes in parameters on the cell performance, both under steady-state conditions (polarization curves) and under forced oscillations (simulating the results of electrochemical impedance spectroscopy)ope

Permanent magnets including undulators and wigglers

After a few historic remarks on magnetic materials we introduce the basic definitions related to permanent magnets. The magnetic properties of the most common materials are reviewed and the production processes are described. Measurement techniques for the characterization of macroscopic and microscopic properties of permanent magnets are presented. Field simulation techniques for permanent magnet devices are discussed. Today, permanent magnets are used in many fields. This article concentrates on the applications of permanent magnets in accelerators starting from dipoles and quadrupoles on to wigglers and undulators.Comment: 45 pages, presented at the CERN Accelerator School CAS 2009: Specialised Course on Magnets, Bruges, 16-25 June 200

Methods Of Analysis For Fermentation Science Products Using Various Analytical Techniques

Fermentation science, the study of microorganisms as they digest food sources to produce usable products for consumption, has been around since the dawn of modern civilization. Historically, the fermentation process has been utilized for the production of alcoholic beverages. More recently, however, the production of bioethanol and biodiesel as a fuel source alternative to classical fossil fuels has gained increased popularity. As with any synthetic process, derivations and optimizations for ideal production are needed. As such, analytical techniques must be implemented to ensure quality control and pinnacle efficiency. This body of work describes analytical techniques providing key qualitative and quantitative information about various steps in the fermentation process. Experiences and conclusions drawn about biofuel production are described in two quantitative projects: Storage Analysis of Sugar Saccharification using Ultrahigh Performance Liquid Chromatography using Corona Charged Aerosol Detection (UPLC-CAD), and Thermal Energy Quantitation of Residual Biomass Using Oxygen Bomb Calorimetry (OBC). The first major technique employs liquid chromatography to separate and quantitate major sugars (xylose and glucose) in the saccharification of biomass (switchgrass). Storage conditions can determine the economic viability of switchgrass as an alternative fuel source. As such, the extent of degradation of switchgrass over a course of one year, and limitations of useable sugars produced needed to be assessed. Results showed no significant loss in sugar production over the course of one year from three distinct storage conditions. From an industrial perspective, this provides low cost storage with minimal to no loss in bioethanol and biodiesel. In addition to biofuels, biomass, switchgrass for example, can be used directly as a combustion source to produce thermal energy. The energy produced (BTU/lb.) can be used mainly to power boiler systems or residential stoves to provide heat, and electricity through a steam turbine. Using OBC, the amount of thermal energy produced by biomass, was obtained and similar degradation studies were accessed. As with the sugar production, the extent of degradation was found to be insignificant. An additional preliminary study explored as an alternative to the pretreatment phase: Ionic Liquid (IL) pretreatment of lignin, characterized by Direct Analysis in Real Time Mass Spectrometry (DART-MS). The goal of these projects was the development of methods to characterize and quantitate specific products during major stages of biofuel production applied which can be easily to many fermentation studies. These methods can then be used as a template for further fermentation studies, both in biofuel and alcoholic beverage production

Nanotechnology Publications and Patents: A Review of Social Science Studies and Search Strategies

This paper provides a comprehensive review of more than 120 social science studies in nanoscience and technology, all of which analyze publication and patent data. We conduct a comparative analysis of bibliometric search strategies that these studies use to harvest publication and patent data related to nanoscience and technology. We implement these strategies on 2006 publication data and find that Mogoutov and Kahane (2007), with their evolutionary lexical query search strategy, extract the highest number of records from the Web of Science. The strategies of Glanzel et al. (2003), Noyons et al. (2003), Porter et al. (2008) and Mogoutov and Kahane (2007) produce very similar ranking tables of the top ten nanotechnology subject areas and the top ten most prolific countries and institutions.nanotechnology, research and development, productivity, publications, patents, bibliometric analysis, search strategy

Toxicological and ecotoxicological pressure due to pesticide use in Sancti Spíritus, Cuba

Aim of study: To quantify the toxicity and ecotoxicological pressure of pesticides in Sancti Spiritus province, Cuba, between 2011 and 2014. Material and methods: A longitudinal descriptive study was designed for the study period, to identify potential risks to the environment and human health associated with the use of pesticides. In order to determine the toxicity and ecotoxicity of pesticide use, Sigma Seq (Spread equivalents), POCER (Pesticide Occupational and Environmental Risk) indicator, and the Toxic Load (TL) methodology of the Plant Health Cuban Institute were used. Main results: Corresponding to 62 chemical families, 124 active ingredients were applied in the province during the study period. Organophosphates, carbamates, pyrethroids, inorganic compounds (such as copper), dithiocarbamates, aryloxyphenoxypropionates, neonicotinoids, sulfonylurea, triazoles, and organochlorines predominated due to their frequency of use. Use of toxic-pesticides, lack of personal protection equipment amount others made workers, residents and applicators the toxicological modules with the highest risk of exposure. From the POCER results we found that aquatic organisms, persistence, and groundwater are the modules with the highest ecotoxicological pressure. Research highlights: With the use of the POCER indicator as well as Sigma Seq, a more accurate assessment of toxicity and ecotoxicity from certain pesticide can be done instead of the TL equation currently used in Cuba. In addition substitution of the most toxic pesticides by less toxic ones could help to reduce synthetic pesticide pressure on humans and the environment. This study can help to develop policies and management practices to reduce the hazards of synthetic pesticide use in Cuba