Penning Source Research Articles

The vital role of community in open source software development: A framework for assessment and ranking

AbstractOpen source software (OSS) follows a software development paradigm whereby self‐motivated volunteers scattered all around the globe contribute to the development in the form of code, documentation, feedback, feature recommendations, bug reporting, and bug resolution. These volunteers, commonly referred to as OSS project community, serve as the foundation of the OSS project, fostering its creation and sustenance and providing long‐term support. The quality and sustainability of the OSS project is reliant upon the development and structure of the self‐governing community. When a business organization plans to acquire an OSS solution, it not only takes into consideration the factors such as reliability, security, and scalability but also attaches significant importance to the likelihood of the OSS project being maintained and supported in the future so that it can rely on it as a stable and secure technology solution. Modern cloud‐based software hosting platforms, such as GitHub, offer a range of options for automatically and freely accessing the complete development history of millions of OSS projects. This easy availability of detailed development history has enabled researchers to analyze and draw quantitative and scientific inferences about the quality of an OSS project which generally involves assessing three aspects, namely, software product, development process, and project community. With focus on project community part, a Framework for Assessment and Ranking of OSS Community is being presented in the current research work, following a detailed examination of the largest source code hosting and project collaboration platform, GitHub. Technique for Order of Preference by Similarity to Ideal Solution from Multi‐Criteria Decision‐Making toolkit has been utilized for assessing the quality of the project community. The framework has been validated by applying it on nine OSS projects and comparing the results with the outcomes obtained through an existing OSS evaluation methodology. The comparative analysis demonstrated that the proposed framework aligns with the aforementioned evaluation methodology while offering an opportunity for in‐depth analysis on the dynamics of volunteer communities, which is lacking in previous evaluation methods. These insights can prove valuable for both potential adopters and project maintainers, aiding them in making informed strategic decisions.

Azimuthal and axial dispersion relations of low-frequency oscillations in partially magnetized plasma with crossed electric and magnetic fields

This paper presents the results of the azimuthal and axial wave diagnostics of a partially magnetized E × B Penning source. Various probes were employed, namely, a two-tip probe for azimuthal waves and two- and four-probe arrays for axial waves, to investigate the spatial characteristics of the instability using a two-point probe technique. The azimuthally aligned tips of the two-tip probe facilitated the investigation of the evolution of the azimuthal dispersion relation, which exhibited a well-known azimuthally propagative spoke at low discharge voltages. By utilizing axially aligned four-probe arrays with a probe distance of 3 mm and two-probe arrays with a relatively long probe distance of 20 mm, we sought to determine whether the rotating spoke propagated in the axial direction in the cylindrical E × B source. Our findings suggest that the rotating spoke originated near the axial center and propagated toward each cathode, rotating in a direction tilted from the azimuthal direction.

Improving pixel‐based classification of GRASS GIS with support vector machine

AbstractOpen source GIS software GRASS releases 8.0 to 8.4 have received some long overdue improvements in imagery handling such as the ability to reuse spectral signature files of existing classifiers, machine readable output of accuracy assessment tool and a support vector machine (SVM) classifier. Practical comparison of all three pixel‐based classifiers of GRASS GIS indicated that the maximum likelihood discriminant analysis classifier is the fastest and least accurate one, followed by a sequential maximum a posteriori classifier with reasonably fast execution time and good accuracy. The newly added SVM classifier is the slowest one but provides the highest accuracy and also shows the highest improvement potential by hyperparameter optimization. To illustrate the capabilities of the core classifiers, a showcase is presented where a single Sentinel 2 image is classified to distinguish 18 crop types using all three classifiers available in GRASS.

A resilience‐based framework for assessing the evolution of open source software projects

AbstractOpen source software (OSS) has been developing for more than two decades. It originated as a movement with the introduction of the first free/libre OSS operating system, became a popular trend among the developer community, led to enterprise solutions widely embraced by the global market, and began garnering attention from significant players in the software industry (such as IBM's acquisition of RedHat). Throughout the years, numerous software assessment models have been suggested, some of which were created specifically for OSS projects. Most of these assessment models focus on software quality and maintainability. Some models are taking under consideration health aspects of OSS projects. Despite the multitude of these models, there is yet to be a universally accepted model for assessing OSS projects. In this work, we aim to adapt the City Resilience Framework (CRF) for use in OSS projects to establish a strong theoretical foundation for OSS evaluation focusing on the project's resilience as it evolves over time. We would like to highlight that our goal with the proposed assessment model is not to compare two OSS solutions with each other, in terms of resilience, or even do a resilience ranking between the available OSS tools. We are aiming to investigate resilience of an OSS project as it evolves and identify possible opportunities of improvements in the four dimensions we are defining. These dimensions are as follows: source code, business and legal, integration and reuse, and social (community). The CRF is a framework that was introduced to measure urban resilience and most specifically how cities' resilience is changing as they evolve. We believe that a software evaluation model that focuses on resilience can complement the pre‐existing models based on software quality and software health. Although concepts that are related to resilience, like sustainability or viability, already appear in literature, to our best knowledge, there is no OSS assessment model that evaluates the resilience of an OSS project. We argue that cities and OSS projects are both dynamically evolving systems with similar characteristics. The proposed framework utilizes both quantitative and qualitative indicators, which is viewed as an advantage. Lastly, we would like to emphasize that the framework has been tested on the enterprise software domain as part of this study, evaluating five major versions of six OSS projects, Laravel, Composer, PHPMyAdmin, OKApi, PatternalPHP, and PHPExcel, the first three of which are intuitively considered resilient and the three latter nonresilient, to provide a preliminary validation of the models' ability to distinguish between resilient and not resilient projects.

Experimental evidence of various mode numbers of azimuthal waves in an Penning source for semiconductor processing

This study presents the first experimental evidence for the existence of various mode numbers of azimuthal waves in an E × B Penning source used for semiconductor processing. To accurately measure these mode numbers, we utilized an eight-tip probe array aligned in an azimuthal direction to acquire spatiotemporal signals and applied the Beall analysis to obtain the dispersion relations. We combined seven dispersion relations obtained from distinct probe pairs to derive a single dispersion relation. This method allowed us to enhance the accuracy and reliability of the measurements. Our results show that the amplitude of the fast Fourier transformation (FFT) undergoes significant changes as the discharge voltage and magnetic field strength are varied. We observed that a distinguishable peak seen at higher discharge voltage is divided into a wide range of dominant peaks up to eight when the discharge voltage is decreased. The dispersion relation reveals that the phase velocity of each mode is proportional to the frequency. As the magnetic field strength increases, the amplitude of the FFT rapidly decreases except for a dominant peak corresponding to mode number 3. Ultimately, the low azimuthal mode dominates the azimuthal oscillation. Moreover, the radial profile of the FFT results shows that the frequencies of modes are nearly constant along the radial direction and have a maximum spectral magnitude at the periphery of the plasma core. Notably, as the amplitude of the modes increased, the maximum amplitude transitioned away from the core region. The findings from experiment with the multi-arrayed probe suggest the presence of a characteristics eigenmode in the E × B Penning source. This eigenmode appears to be a fundamental and pervasive feature of the system, spanning a range of mode numbers from low to high.

Estimating the GDP effect of Open Source Software and its complementarities with R&D and patents: evidence and policy implications

AbstractOpen Source Software (OSS) has become an increasingly important knowledge asset in modern economies. However, the economic impact of OSS on countries’ GDP is ambivalent due to its public good character. Using a cross-country panel from 2000 to 2018, including 25 of the largest EU countries plus the USA, Japan, Korea, Canada, China, Norway, and Switzerland, matching OSS commits to GitHub to macroeconomic data provided by the OECD, our results confirm the dual nature of OSS. On the one hand, the open-access character creates great learning potential by providing a commonly accessible productive resource for all countries. On the other hand, it creates outward-directed spillovers associated with own OSS contributions. Accordingly, on average, we find that countries experience an increase in GDP when the world stock of OSS grows. However, smaller countries experience a decline in GDP resulting from their own contributions due to knowledge spillovers. The net effect is nonetheless positive. If no country contributed to OSS development, GDP for the average country would be 2.2% lower in the long run. Moreover, the losses associated with unintended spillovers are lower for countries with a higher R&D and patenting intensity. Based on our findings, we derive implications for policies and regulations concerning OSS.

Rotating spoke frequency in E × B penning source with two-ion-species plasma

In E B sources with different degrees of magnetization between electrons and ions, collisionless Simon–Hoh instability is prone to be induced, which may result in long-wavelength and low-frequency plasma oscillations along the azimuthal direction known as the rotating spoke. Recent studies have shown that the inertial response of unmagnetized ions is a key factor that affects the rotating spoke frequency, and in-depth studies on the correlation between the ion mass and spoke frequency have been conducted for various types of E B sources (e.g. Hall thruster, magnetron and Penning sources). In the case of the E B Penning source where the generation of desired ion species is maximized through molecular gas discharge, the intrinsic characteristics of the instability dependent on the ion mass inevitably require consideration of the coexistence of various ion species. In this work, we experimentally studied the spoke in the E B Penning source with two-ion-species plasma. By adjusting the mixture ratio of argon and krypton gases, we investigated the changes in instability frequency with electrical diagnostics. Two frequency peaks were clearly observed, with the peaks of lower and higher frequencies corresponding to mode numbers 2 and 3, respectively. The frequencies of each peak shifted to higher values when the argon content in the gas mixture was increased. Finally, the theoretical scaling of the spoke suggests that the changes in the frequencies are proportional to the inverse square root of the effective ion mass.

Improving the detection of community smells through socio‐technical and sentiment analysis

AbstractOpen source software development is regarded as a collaborative activity in which developers interact to build a software product. Such a human collaboration is described as an organized effort of the “social” activity of organizations, individuals, and stakeholders, which can affect the development community and the open source project health. Negative effects of the development community manifest typically in the form of community smells, which represent symptoms of organizational and social issues within the open source software development community that often lead to additional project costs and reduced software quality. Recognizing the advantages of the early detection of potential community smells in a software project, we introduce a novel approach that learns from various community organizational, social, and emotional aspects to provide an automated support for detecting community smells. In particular, our approach learns from a set of interleaving organizational–social and emotional symptoms that characterize the existence of community smell instances in a software project. We build a multi‐label learning model to detect 10 common types of community smells. We use the ensemble classifier chain (ECC) model that transforms multi‐label problems into several single‐label problems, which are solved using genetic programming (GP) to find the optimal detection rules for each smell type. To evaluate the performance of our approach, we conducted an empirical study on a benchmark of 143 open source projects. The statistical tests of our results show that our approach can detect community smells with an average F‐measure of 93%, achieving a better performance compared to different state‐of‐the‐art techniques. Furthermore, we investigate the most influential community‐related metrics to identify each community smell type.

Exploring factors affecting developer abandonment of open source software projects

AbstractOpen Source Software (OSS) projects have long been studied to understand the need of community support for their growth and survival. However, there has been limited research on developers' abandonment, though it is found to have detrimental effect on quality and sustainability of OSS projects. This paper examines the impact of developer and project‐related factors on developer abandonment in OSS projects. Factors include developer attributes: experience, role, coding language, and joining date, and project attributes: change complexity and sentiments in commit logs. The findings are (1) for developer experience, core/non‐core member, and joining date; there exists a pattern of developers abandoning the projects. (2) There is no definite answer for coding language. (3) It does not relate to the change profile of a project except a few indicators. Sentiments can also not be linked. These results provide OSS community and researchers with useful insights on developer abandonment and the factors influencing it or not.

Efficiency improvement of an E × B Penning discharge source by enhanced cross-field transport of electrons

Precise control of the particle motion in externally applied electric and magnetic fields is of great significance in the development of the E × B source to generate high-density plasma and deliver a stable ion beam current. Especially, in the E × B Penning discharge source, the heating and energy relaxation of the beam electrons is concentrated in the plasma column along the magnetic field line. Plasma researchers have thus far focused on the relevant physical phenomena of the partially magnetized plasma that arises from the gradient of the plasma properties in the E × B Penning source. Here, we point out that current methods of radially centered electron confinement do not guarantee efficient ion beam extraction, and newly introduce the improvement of the efficiency of a cylindrical E × B Penning source targeting radial extraction of ion beam. We concentrate on the method to enhance the cross-field transport of electrons toward the extraction region. The generation of a spatially asymmetric sheath structure allows the beam and energetic electrons to be transported to the extraction region via the E × B drift of the electrons. The transported electrons contribute to expansion of the electron heating and ionization regions to the extraction region by breaking of axial symmetry of the sheath, thereby increasing the temperature and density of the electrons in the extraction region as the magnetic field strength increases. The enhanced discharge efficiency defined as the ratio of the electron density to the discharge current is noticeable, recording approximately twice the improved efficiency compared to the conventional mode with symmetric sheath structure.

DEVELOPMENT OF OPEN SOURCE HARDWARE IN ONLINE COMMUNITIES: INVESTIGATING REQUIREMENTS FOR GROUPWARE

AbstractOpen source hardware is hardware whose design is shared online so that anyone can study, modify, distribute, make, and sell it. In spite of the increasing popularity of this alternative IP management approach, the field of OSH remains fragmented of diverse practices seeking for settlement. This challenges providers of groupware solutions to capture the specific needs of open source product development practitioners. This contribution therefore delivers a list of basic requirements and verifies them by comparing offered functions of existing groupware solutions.

Modeling and simulation of firm-leading self-organization evolution process in open source product design project

ABSTRACTOpen source product design is characterized by dynamic evolution, autonomous task control, loose organization structure, and frequent collaboration, which shows the process is full of high uncertainty. Firms have used this innovation pattern to obtain ideas. To describe the firm-leading self-organization evolution process, an agent-based modeling and simulation method is applied. We have proposed an agent-based model including designers and firms in light of Complex Adaptive System theory firstly; Secondly, their behaviors, especially the two typical behaviors: task selection and plan screening are illustrated; Finally, the simulation results show that:1) evolution process of agent, product, and community can be described clearly by simulation. Agent-based simulation can support the analysis, evaluation and optimization of the evolution process;2) in task selection phase: firm’s recommendation can improve the evolution efficiency;3)in plan screening phase, firms’ “control” also plays important role in the evolution process, but the impact of designer agents’ self-organization cannot be ignored.

Open Source Hardware Communities: Investigating Participation in Design Activities

AbstractOpen source design of hardware products is an emerging phenomenon that takes more and more importance today's in the society. However, open source (hardware) design implies a tremendous change in both design practices and philosophy because it is partly related to the movements of creative commons and the sharing economy. From this perspective one could think that participation is crucial in the success of open source design projects. In this paper, we analyse 9 case studies in the light of 3 hypotheses. If many studies highlight the potential of the crowd as a resource for design tasks, our study shows that for open source design communities the participation is not massive. In this study, we used an activity-based approach to build our model. As open source design processes are fairly unstructured and based on voluntary participation, it is impossible to adopt a classical task-based model. With the help of this model, we were able evaluate the overall size of the active community, the participation rate with regards to the activities. This study paves the way to deeper and extensive studies on how to support communities engaged in open source design of hardware products.

Discovering community patterns in open-source: a systematic approach and its evaluation

“There can be no vulnerability without risk; there can be no community without vulnerability; there can be no peace, and ultimately no life, without community.” - [M. Scott Peck]The open-source phenomenon has reached the point in which it is virtually impossible to find large applications that do not rely on it. Such grand adoption may turn into a risk if the community regulatory aspects behind open-source work (e.g., contribution guidelines or release schemas) are left implicit and their effect untracked. We advocate the explicit study and automated support of such aspects and propose Yoshi (Y ielding O pen-S ource H ealth I nformation), a tool able to map open-source communities onto community patterns, sets of known organisational and social structure types and characteristics with measurable core attributes. This mapping is beneficial since it allows, for example, (a) further investigation of community health measuring established characteristics from organisations research, (b) reuse of pattern-specific best-practices from the same literature, and (c) diagnosis of organisational anti-patterns specific to open-source, if any. We evaluate the tool in a quantitative empirical study involving 25 open-source communities from GitHub, finding that the tool offers a valuable basis to monitor key community traits behind open-source development and may form an effective combination with web-portals such as OpenHub or Bitergia. We made the proposed tool open source and publicly available.

Energy & mass-charge distribution peculiarities of ion emitted from penning source

The optimization of hydrogen Penning sources used, in particular, in plasma chemical processing of materials and DLC deposition, is still very important. Investigations of mass-charge composition of these ion source emitted beams are particular relevant for miniature linear accelerators (neutron flux generators) nowadays. The Penning ion source energy and mass-charge ion distributions are presented. The relation between the discharge current abrupt jumps with increasing plasma density in the discharge center and increasing potential whipping (up to 50% of the anode voltage) is shown. Also the energy spectra in the discharge different modes as the pressure and anode potential functions are presented. It has been revealed that the atomic hydrogen ion concentration is about 5-10%, and it weakly depends on the pressure and the discharge current (in the investigated range from 1 to 10 mTorr and from 50 to 1000 μA) and increases with the anode voltage (up 1 to 3,5 kV).

Marsobot: design and performance characterization of a low-cost, ground-based multispectral camera on an open source rover

ABSTRACTOpen source, low cost sensors, and robotic systems have developed to the point of being able to produce meaningful, repeatable results in real-life applications. We developed a low-cost, open source multispectral camera mounted on a small custom-built robotic rover. We compared the performance of our camera with a commercial multispectral camera and a laboratory spectrometer using minerals commonly found on Mars that exhibited different reflectance values in visible and near-infrared wavelengths. Our camera performed favourably when compared to the commercial instruments. It is a very cost effective solution for operating in extreme situations, where damage to instruments is possible. Our total system of rover and sensor would, therefore, be very useful for operating in delicate and inaccessible environments where damage to the area under investigation and to human observers is of concern.

An Applied Approach to Teach Hospital Information Systems Development Using an Open Source ERP Framework

The objective of the paper is to represent an international pilot project to teach development of free and open source hospital Information systems at the national level using a live pre installed Enterprise Resource Planning (ERP) System. We have developed live image with pre installed free and open source ERP framework -Tryton® (A fork of openERP®) and a free and o pen source health and hospital information system GNU Health® that supports electronic medical records (EMR) which is developed on top of the ERP framework as the second layer. We considered the two layer system as a domain specific application development framework for further agile development of information systems in the healthcare information technology area. Participants were health informatics professionals invited from ministry of health from selected developing countries to participate in the ERP training program at United Nations University International Institute for Global Health (UNUIIGH) to learn agile development of open source hospital information system based on the ERP concept to adopt the solution in pub lic hospitals and clinics in their respective country. During three days extensive course, participants used a live image of pre installed ERP system and a cloud hosted ERP configured as a distributed clinical information system to support the training and they learned how to configure the solution in a practical and step by step procedure. We have evaluated the course including feedback from the participants through a questionnaire and interview. The result showed a great potential of live open source ERP tools to support the training. It is expected that the results can be used for improvement of development of the other courses in other universities and institutions especially for subjects covering implementation procedures and critical success factors of free and open source ERP framework adoption in hospitals and Health centers with more focus on rural areas. © 2013 The Authors. Published by Elsevier B.V. S election and peer-review under responsibility of the Faculty of Information Science & Technology, Universiti Kebangsaan Ma laysia.

Simulation study on hydrogen penning source discharge at low pressure

In order to better comprehend the dynamic behaviours of ion and electron during the Penning source discharge process under a low pressure and weak ionization condition, numerical simulation is carried out to study the penning source discharge and diffuse process. For constituting 2D axial symmetrical model and combining the particle simulation and Monte Carlo (PIC/MCC) method, elastic collision, excitation, and ionization reactions between electrons and hydrogen molecules, hydrogen atom and ions are taken into account. The effect of magnetic field configuration, secondary electron emission coefficient, derivational voltage, and gas pressure on the discharge characteristics is investigated. It has been found that the simulant discharge parameters, including electron and ion densities, anodic current and ionic current, H+ and H2+ densities, etc, are in good agreement with the experimental results. Based on our numerical simulation, the study of the hydrogen penning discharge is being changed from qualitative analysis to quantitative calculation, which is important for the design and optimization of the penning ion source.

Open source in Swedish companies: where are we?

AbstractOpen Source (OS) is a phenomenon of increasing significance for organizations, offering the prospect of effective alternative business solutions and new business opportunities. A number of surveys have been conducted in various countries with the purpose of understanding the state of practice with respect to OS in companies. In this paper we report on a study of the perceptions of OS and the uptake of OS products and development models in Swedish companies. The study used purposeful sampling of companies that have an expressed interest in OS, and the survey was conducted using a set of pre‐prepared questions. Its goal was to investigate the extent to which OS has influenced business thinking, as seen from the standpoint of stakeholders. We found that uptake is much higher than reported in earlier studies, but as with previous studies, activity is still concentrated in small and medium‐sized enterprises (SMEs). There is increased evidence of interest beyond the simple use of OS components at the infrastructure level. Further, a significant proportion of the companies studied are supporting the OS community as well as benefiting from it. Support includes participation in existing projects and the release of new software under OS licenses.

6.6.2 Integrating Open Source

AbstractOpen source projects are one category of self‐contained software components that should be considered for integration into software intensive system. Benefits and risks, as well as other issues in selection, adoption, maintenance and support of such component are discussed.