Indirectly predicting the maintenance effort of open-source software

Nowadays, Open Source Software (OSS) is widely used and plays a crucial role in the software industry. OSS development is a knowledge-intensive activity that requires very high levels of domain knowledge and needs to maintain the knowledge sharing environment. OSS project develop by the contribution of OSS members on its virtual community where every member can communicate and develop software together. To create new open source software needs the motivation of all members, the resources embedded in the relationship in community and the coordination of members as a virtual team to complete the OSS tasks. This study focused on the knowledge sharing in the OSS project community under the individual motivation, virtual community and virtual team perspectives. We analyzed 304 surveys collected from OSS communities and found that the extrinsic motivation, some perspectives of virtual community such as social interaction, identification and perspective of virtual team – team cognition have a direct impact on knowledge sharing of OSS project community. The study found that all the perspectives of virtual community have a significant impact on team cognition, and therefore have indirect effect on the knowledge sharing in OSS. Moreover, our results indicated that knowledge sharing has a significant impact on project performance. Implications for theory building, practical management and future research are also discussed.

(ProQuest: ... denotes formulae omitted.)1 Research Premises and HypothesisMaintenance costs have a consistent weight in the total costs generated by an application during its entire lifecycle. Previously conducted research and studies that focus on software maintenance support this claim. In [2], the 60/60 rule of software is depicted. The rule claims that maintenance accounts for 60% of the total costs generated by a software in its entire lifecycle. Enhancement or perfective [3] maintenance tasks account for 60% of all the costs generated by maintenance [2], whereas error correction or corrective [3] maintenance tasks account only for 17% of total maintenance costs [2]. In [4] it's stated that software applications evolve over time to meet the changing needs which leads to maintenance generating 67% of the applications total lifecycle costs. In [5] it is argued that maintenance typically accounts for 75% or more of the total software workload. Other relevant research place maintenance costs at 90% [6], 75% [7], 90% [8] or at 60% to 70% [9] of the overall application's lifecycle cost. It is therefore of paramount importance to accurately estimate maintenance cost before implementing a software project in order to better comprehend the total costs associated with developing and owing a software application. Better understanding maintenance costs will provide valuable information regarding resource planning and the appropriate time to decommission the application.The cost of maintenance is directly determined by the number of people involved in the maintenance process and the number of hours each person invests in the maintenance tasks. Thus in order to estimate maintenance cost one needs to estimate the effort invested in the maintenance process. The maintenance effort is expressed in man-hours which entails the number of ours dedicated by the maintenance team to implementing maintenance tasks. Maintenance in web applications has two main components: content maintenance and technical maintenance.Content maintenance requires performing tasks of a non-technical nature like updating product inventory and information, adding news or articles, managing blog posts, updating contact or brand and visual identity information and moderating user comments or messages. Content maintenance team staffing and therefore content maintenance effort is determined by the web application's size [1].According to [1] and as presented in Table 1, content maintenance cost is determined by the number of hours required to keep the web application up to date in terms of content. The larger the application the more hours need to be invested in keeping it up to date in terms of content. The more content changes in an application the more technical maintenance tasks are generated. Technical maintenance tasks are generated because content managers spot bugs or request new functionality to help keep the content up to date. Therefore, content update frequency is a factor that impacts maintenance effort and cost.Technical maintenance requires adding new functionality, performing regular back-ups, monitoring website outages, checking IP reputation, checking DNS configuration, test website speed, check for broken links, perform software updates if third party software was used when developing the web application, monitor traffic statistics and review search engine indexing.According to [1] and as presented in Table 2, technical team stuffing is determined by the level of complexity built into the web application. Thus, a Basic web application which is characterized by static content build mainly using front-end technologies like HTML, CSS and JavaScript will require no more than 1 person to perform maintenance tasks. A Dynamic web application which stores its content in a database and has functionality which is powered by PHP, Java, ASP.NET, Python, Ruby or any other high-level programming language will require 1 to 2 persons to perform maintenance tasks. …

In this paper, we study oligopolistic competition between closed and open source softwares. By intersecting existing economic contributions on open source, we propose a two stage game with perfect information and product di¤eretiation in which producers firstly set softwares quality, then they determine prices (constrained at zero for open source programs). In doing this, we explicitly model lock-in e¤ects, network externality components of software quality as well as knowledge accumulation in software use and implementation. With respect to a monopolistic benchmark case, we argue that in duopoly a pro- prietary sofware producer facing an open source software will reduce its selling price whether: (i) its network of users is larger than open sources one and its consumers are largely experienced on its program, (ii) it has a small network of un-skilled consumers. In opposition, after open source softwares emergence, proprietary software price does augment if proprietary software users form a large, but poorly skilled network. Fur- thermore, we show that, in all above cases, proprietary software quality increases because of the existence of a open source alternative to a previouisly monopolistic program. Finally, by modeling knowledge accumulation processes through di¤erence equations, we show that the ratio between closed and open source programs opportunity costs of software learning and deployment plays a crucial role in shaping market outcomes. Until an open source software remains too complex and technical for unskilled or time-scarse users, a shared market solution in which both softwares are adopted is predicted. In contrast, if opportunity costs in learning and understanding open source programs are remarkably low, or at least equal to opportunity costs of a closed source software, then a open source dominance outcome (i.e. all software are open ones) phases out.

Open Source Software (OSS) projects rely on the efforts of thousands of software developers. The sustainability and diversity of these communities are two important factors for the longterm viability of OSS communities. This paper reviews the research on OSS sustainability and diversity. Drawing on the findings of measures on sustainability and diversity, we applied a number of the established metrics to the Android Open Source Project and found that over a third of all contributions originate from Google. Surprisingly, in 2015 we saw a decrease in the total number of contributors within the Android project. Findings from our analysis highlight the importance of sustainability and diversity for the development of OSS.

Open Source vs. Proprietary Software: Competition and Compatibility

Open-source software abbreviated as OSS is computer software that is available with source code and is provided under a software license that permits users to study, change, and improve the software. For the commercial software the source code and certain other rights are normally reserved for copyright holders,i.e. the company who developes the software. A group of people in a collaborative manner often developes the Open source software, not under the roof of a large organization. This strategy makes open source software cheap, reliable and modifiable if needed. In this context we shall discuss mainly the features of Open Source Software, differences of open source and free software and open source software movement in Indian perspective.

Requirement of software is necessary for the process system-computer simulation. ln reality, costly of software is one of restriction for the software development. However, the costly constraint can be solved using open source software such as Scilab and OpenOffice. The goa lof this article formulates user friendly program of the process system. Scilab program by Graphical User Interface (GUI) and interaction with Open Office-Cale for the data-base physical property. Scilab program has been listed in this article and algorithme of rhe program as the methodology has been presented in this article. Results of the simulation program indicate goodfinding for the process system. Kata kunci : scilab; open office, simulasi komputer; oss (open source sortuare), Antar Muka Pcngguna - Graphical User Interface (GUI).

Preface The present proceedings consists of the outcomes of the 7.5 hec master/PhD course ’CFD with OpenSource Software’, 2016. The course gives an introduction to the use of OpenSource software for CFD applications. It has a strong focus on how to efficiently use the Linux operating system and different softwares that are useful for CFD. A major individual project work in OpenFOAM forms a large part of the course. The project is defined according to the student’s special interests. The result of the project is a detailed tutorial for a specific application or library of OpenFOAM, which is presented to, and peer-reviewed by the students. The tutorials thus form a part of the course (Docendo discimus - Latin: ’by teaching, we learn’). The tutorials are made available through the proceedings, as a contribution to the OpenFOAM community, and to contribute to global learning. The tutorials are typically made available in the form of a report, a set of slides, possible source code, possible cases, and additional material, to be downloaded at http://www.tfd.chalmers.se/~hani/kurser/OS_CFD, under the corresponding year. The main requirements of a tutorial is that it should consider the following four aspects: • How to use it. • The theory of it. • How it is implemented. • How to modify it. This should be reflected by the specified learning outcomes of each tutorial, and should be evaluated by a set of study questions. It should be recognized that the tutorials are student project work, done as part of a course. For many of the students it is the first time they are introduced to OpenFOAM, C++ and object oriented programming, and some of the students have limited previous experience with Linux. Any reader should be aware that the tutorials might not be free of errors. Still, the tutorials might be useful for someone who would like learn something similar as the students learnt while doing the project work. The material has gone through a review process. The role of the reviewers is to go through the tutorial and make sure that it works, that it is possible to follow, and to some extent correct the writing. The reviewers have no responsibility for the contents, and it is thus up to the reader to make sure that any work that is derived from one of the tutorials is verified and validated. The Editor: Prof. Hakan Nilsson (Chalmers University of Technology)

Open source software (OSS) is computer software that has its underlying source code made available under a licence. This can allow developers and users to adapt and improve it (Raymond, 2001). Computer software can be broadly split into two development models: • Proprietary, or closed software, owned by a company or individual. Copies of the binary are made public; the source code is not usually made public. • Open-source software (OSS), where the source code is released with the binary. Users and developers can be licenced to use and modify the code, and to distribute any improvements they make. Both OSS and proprietary approaches allow companies to make a profit. Companies developing proprietary software make money by developing software and then selling licences to use the software. For example, Microsoft receives a payment for every copy of Windows sold with a personal computer. OSS companies make their money by providing services, such as advising clients on the GPL licence. The licencee can either charge a fee for this service or work free of charge. In practice, software companies often develop both types of software. OSS is developed by an ongoing, iterative process where people share the ideas expressed in the source code. The aim is that a large community of developers and users can contribute to the development of the code, check it for errors and bugs, and make the improved version available to others. Project management software is used to allow developers to keep track of the various versions. There are two main types of open-source licences (although there are many variants and subtypes developed by other companies): • Berkeley Software Distribution (BSD) Licence: This permits a licencee to “close” a version (by withholding the most recent modifications to the source code) and sell it as a proprietary product; • GNU General Public Licence (GNU, GPL, or GPL): Under this licence, licencees may not “close” versions. The licencee may modify, copy, and redistribute any derivative version, under the same GPL licence. The licencee can either charge a fee for this service or work free of charge. Free software first evolved during the 1970s but in the 1990s forked into two movements, namely free software and open source (Berry, 2004). Richard Stallman, an American software developer who believes that sharing source code and ideas is fundamental to freedom of speech, developed a free version of the widely used Unix operating system. The resulting GNU program was released under a specially created General Public Licence (GNU, GPL). This was designed to ensure that the source code would remain openly available to all. It was not intended to prevent commercial usage or distribution (Stallman, 2002). This approach was christened free software. In this context, free meant that anyone could modify the software. However, the term “free” was often misunderstood to mean no cost. Hence, during the 1990s, Eric Raymond and others proposed that open-source software was coined as a less contentious and more business-friendly term. This has become widely accepted within the software and business communities; however there are still arguments about the most appropriate term to use (Moody, 2002). The OSMs are usually organised into a network of individuals who work collaboratively on the Internet, developing major software projects that sometimes rival commercial software but are always committed to the production of quality alternatives to those produced by commercial companies (Raymond, 2001; Williams, 2002). Groups and individuals develop software to meet their own and others’ needs in a highly decentralised way, likened to a Bazaar (Raymond, 2001). These groups often make substantive value claims to support their projects and foster an ethic of community, collaboration, deliberation, and intellectual freedom. In addition, it is argued by Lessig (1999) that the FLOSS community can offer an inspiration in their commitment to transparency in their products and their ability to open up governmental regulation and control through free/libre and open source code.

The Move to the Middle: Convergence of the Open-Source and Proprietary Software Industries

The main aim of this paper is to present a geoportal that may help with and speed up the process of land consolidation by providing spatial information about land consolidation plans to all landowners. The geoportal construction is based on free and open source software. The proposed geoportal allows participants to view the land consolidation and exchange project, and also to search for parcels and registered land units. The paper presents opportunities of software and functionality of geoportal on the example of consolidation zone - Łukowa commune. Software and tools for the geoportal creation will facilitate sharing of up-to-date information about the location of the land before, during and after the consolidation process. The geoportal will improve the communication between surveyors-designers and landowners, which undoubtedly will help and shorten conducting of so complicated process of land consolidation.

In the biometrics community, face and speaker recognition are mature fields in which several systems have been proposed over the past twenty years. While existing systems perform well under controlled recording conditions, mismatch caused by the use of different sensors or a lack of cooperation from the subject still significantly affects performance, especially in challenging scenarios such as in forensics. Furthermore, existing methods suffer from scalability issues, which prevents them from taking advantage of increasingly large amounts of training data. This is otherwise a promising approach to improve accuracy in such challenging scenarios. In this thesis we address these problems of mismatch and complexity by developing scalable probabilistic models that we apply to face, speaker and bimodal recognition. Our contributions are four-fold. First, we propose a unified framework for session variability modeling techniques based on Gaussian mixture models (GMM), that encompasses inter-session variability (ISV) modeling, joint factor analysis (JFA) and total variability (TV) modeling. Second, we propose a novel exact and scalable formulation of probabilistic linear discriminant analysis (PLDA), which is a probabilistic and generative framework that models between-class and within-class variations. This formulation solves a major scalability issue, by improving both the time complexity of the training procedure from cubic to linear with respect to the number of samples per class, and the complexity of the scoring procedure. Furthermore, the implementations of all the proposed techniques are integrated into a novel collaborative open source software library called Bob 1 that enforces fair evaluations and encourages reproducible research. Fourth and finally, large-scale experiments are conducted with all of the above machine learning algorithms on several databases such as FRGC for face recognition, NIST SRE12 for speaker recognition and MOBIO for bimodal recognition, showing competitive performances.

Background and Purpose: The health sector in many developing countries, especially in sub-Saharan Africa, suffers since a long time from poor health information collection and analysis systems. This study evaluates the results of 3 projects financed by the Migration for Development in Africa-Great Lakes (MIDA GL) program in 3 Rwandan hospitals: Kigali University Teaching Hospital (CHUK), Neuro-psychiatric hospital Caraes-Ndera (NPH-CN) and Gihundwe district hospital (GDH). These projects aimed to empower hospital staff in collecting and analyzing hospital information by using OpenClinic, an open source hospital information management system. Methods: The first analysis at CHUK used the results of a CAP (competence, ability, practice) survey addressed to healthcare staff in using OpenClinic, in 2010 and 2012. The second method analyzed results of NPH-CN and GDH in the OpenClinic software utilization between 1/1/2011 and 31/12/2012. Results: Results showed that routine OpenClinic utilization increased by 20% (from 36.0% to 56.3%) at CHUK between 2010 and 2012 and skills levels increased significantly in admission (+9.2%) and laboratory (+10.0%) departments where the training programs were run. The results obtained from the hospitals of Gihundwe and Ndera showed that the 2 hospitals almost doubled their income one year after implementation and indicators like case load, encounter load and numbers of provided health care deliveries continue to increase linearly, demonstrating the continuity of OpenClinic utilization. Clinical modules however have not yet been well adopted in Ndera and Gihundwe: reason for encounter documentation and diagnostic coding are not being performed systematically. Conclusion: The MIDA GL funding allowed 3 Rwandan hospitals to implement the OpenClinic tool easily and to improve its utilization by gathering and centralization of health information in real-time. The improvement of user skills level in OpenClinic enabled them to take ownership of the tool proving the need for regular staff training and evaluations in the OpenClinic utilization. Keywords: MIDA, Empowering healthcare staff, OpenClinic utilization, Hospital information system, Rwanda

Open Source Software is becoming evermore important and widespread these days. However, their maintenance processes are commonly unknown even they are controlled with defect management and version management systems. These systems have been studied separately in earlier studies. Therefore, in this paper, we present a system, Remote Analysis System Open Source Software (RaSOSS), for analyzing maintenance process through both systems. The system retrieves data from the defect management and version management systems for analysis. Analysis provides attributes that evaluated generally project, defect management process and version management. We used Apache HTTP Server as a case study to explain results of provided analysis.

Pengembangan perangkat lunak adalah tugas kompleks dan membutuhkan adaptasi untuk mengakomodasi kebutuhan pengguna. Untuk membuat konsep dan perubahan perangkat lunak, dalam pemeliharaan, sekarang telah dikembangkan lebih mudah dalam pengembangan perangkat lunak, pola model-view-controller, yang merupakan arsitektur yang dapat membantu memfasilitasi dalam pengembangan dan pemeliharaan perangkat luna. Hal ini, karena dalam arsitektur model tiga-lapis, yaitu: tampilan dan pengontrolan dalam pembangunan dilakukan secara independen, sehingga dapat memberikan dahan dalam pengembangan dan pemeliharaan. Selain itu, arsitektur ini juga dapat melihat hal-hal yang sederhana dan menarik bagi pengguna. Software sistem on-line test adalah perangkat lunak yang memerlukan interaksi dengan pengguna, dan pemeliharaan perangkat adaptif. Karena sistem ujian on-line memerlukan pengembangan perangkat lunak untuk mengakomodasi kebutuhan ini berkembang dengan cepat. Makalah ini untuk menganalisis Model-View-Controller dan mencoba pembangunan, untuk menerapkannya dalam pengembangan perangkat lunak sistem pengujian on-line.