A Framework for Seamless Variant Management and Incremental Migration to a Software Product-Line

Context: Software systems often need to exist in many variants in order to satisfy varying customer requirements and operate under varying software and hardware environments. These variant-rich systems are most commonly realized using cloning, a convenient approach to create new variants by reusing existing ones. Cloning is readily available, however, the non-systematic reuse leads to difficult maintenance. An alternative strategy is adopting platform-oriented development approaches, such as Software Product-Line Engineering (SPLE). SPLE offers systematic reuse, and provides centralized control, and thus, easier maintenance. However, adopting SPLE is a risky and expensive endeavor, often relying on significant developer intervention. Researchers have attempted to devise strategies to synchronize variants (change propagation) and migrate from clone&own to an SPL, however, they are limited in accuracy and applicability. Additionally, the process models for SPLE in literature, as we will discuss, are obsolete, and only partially reflect how adoption is approached in industry. Despite many agile practices prescribing feature-oriented software development, features are still rarely documented and incorporated during actual development, making SPL-migration risky and error-prone.Objective: The overarching goal of this PhD is to bridge the gap between clone&own and software product-line engineering in a risk-free, smooth, and accurate manner. Consequently, in the first part of the PhD, we focus on the conceptualization, formalization, and implementation of a framework for migrating from a lean architecture to a platform-based one.Method: Our objectives are met by means of (i) understanding the literature relevant to variant-management and product-line migration and determining the research gaps (ii) surveying the dominant process models for SPLE and comparing them against the contemporary industrial practices, (iii) devising a framework for incremental SPL adoption, and (iv) investigating the benefit of using features beyond PL migration; facilitating model comprehension.Results: Four main results emerge from this thesis. First, we present a qualitative analysis of the state-of-the-art frameworks for change propagation and product-line migration. Second, we compare the contemporary industrial practices with the ones prescribed in the process models for SPL adoption, and provide an updated process model that unifies the two to accurately reflect the real practices and guide future practitioners. Third, we devise a framework for incremental migration of variants into a fully integrated platform by exploiting explicitly recorded metadata pertaining to clone and feature-to-asset traceability. Last, we investigate the impact of using different variability mechanisms on the comprehensibility of various model-related tasks.Future work: As ongoing and future work, we aim to integrate our framework with existing IDEs and conduct a developer study to determine the efficiency and effectiveness of using our framework. We also aim to incorporate safe-evolution in our operators

Seamless Variability Management With the Virtual Platform

Customization is a general trend in software engineering, demanding systems that support variable stakeholder requirements. Two opposing strategies are commonly used to create variants: software clone & own and software configuration with an integrated platform. Organizations often start with the former, which is cheap, agile, and supports quick innovation, but does not scale. The latter scales by establishing an integrated platform that shares software assets between variants, but requires high up-front investments or risky migration processes. So, could we have a method that allows an easy transition or even combine the benefits of both strategies? We propose a method and tool that supports a truly incremental development of variant-rich systems, exploiting a spectrum between both opposing strategies. We design, formalize, and prototype the variability-management framework virtual platform. It bridges clone & own and platform-oriented development. Relying on programming-language-independent conceptual structures representing software assets, it offers operators for engineering and evolving a system, comprising: traditional, asset-oriented operators and novel, feature-oriented operators for incrementally adopting concepts of an integrated platform. The operators record meta-data that is exploited by other operators to support the transition. Among others, they eliminate expensive feature-location effort or the need to trace clones. Our evaluation simulates the evolution of a real-world, clone-based system, measuring its costs and benefits.Comment: 13 pages, 10 figures; accepted for publication at the 43rd International Conference on Software Engineering (ICSE 2021), main technical trac

Enhanced software product line (ENSPL) for industrial test applications[QA75].

Pendekatan-pendekatan barisan produk perisian masa kini menghasilkan produk perisian yang mempunyai ikatan kuat dengan aset-aset perisian. Current software product lines (SPL) methodologies develop software products in the manner that is tightly coupled to the software assets

A framework to harmonise mineral asset valuation methodologies with existing and emerging financial reporting requirements

A thesis submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy, 2017One of the consequences of globalisation in the extractive industries is the necessity to apply uniform accounting and valuation standards that are clearly understood and consistently applied by the global stakeholder community. At the beginning of the 20th century it was realised, mainly by the major mining countries that the extractive industries is one of the biggest sectors globally. In the extractive industries the single most important asset is the Mineral Resources and Mineral Reserves, yet this is not reflected anywhere in the financial statements. The major mining countries, through their mining institutes, realised that there was a need to develop standards and guidelines to align and standardise the definitions of Exploration Results, Mineral Resources and Mineral Reserves, which was achieved through the CRIRSCO template. From the accounting fraternity, several organisations also realised the need for an accounting standard specific to the extractive industries, specifically for financial reporting. Attempts by the IVSC and IASB to develop a global accounting standard for the extractive industry attests to the global requirement to develop internationally recognised valuation guidelines or a global framework for the valuation of mineral assets. Both the mining institutions and accounting standards setting boards have been working in isolation to develop a globally acceptable standard or guideline for the extractive industries, and neither has been successful due to the inherent complexities. The harmonisation of the national codes for reporting of Mineral Resources and Mineral Reserves through the CRIRSCO template, provides global common understanding. However, the national mineral asset valuation (MAV) codes, are needed to develop a similar international template. The CRIRSCO template provided a strong foundation on which the IMVAL template was developed. As part of this research a framework was developed to harmonise the national MAV Codes. Various authors have argued that there is no globally accepted standard or guideline for the valuation of extractive industries assets, nor is there a specific accounting standard for extractive industries. MAV is still an emerging discipline, coupled with the fact that financial reporting in the mineral industry is not yet fully developed, as IFRS 6 appears to be the only mineral specific financial reporting standard. This is supported by the fact that currently there is a lack of a comprehensive accounting standard for the extractive industries to guide the accounting, recognising and presenting these assets in the primary financial statements. This thesis argues that there is a gap between reflecting and accounting for Mineral Resources and Mineral Reserves in the financial reporting systems, and how these mineral assets are valued and reported. These identified gaps between MAV methodologies and financial reporting requirements formed the basis of this work. Hence this thesis develops a framework to harmonise the existing and emerging financial reporting requirements and MAV methodologies. This framework is applicable to developmental projects and operating mines, and was validated by applying the framework to a real life case study. Turquoise Hill Resources (Turquoise), which owns Oyu Tolgoi copper-gold mine in Mongolia, was selected as a good case study, due to the fact that Turquoise owns and operates this single multicommodity mineral asset, with information available in the public domain. Hence the value of Turquoise on the stock exchange is driven by the fundamental value of the mineral asset only. The results of the proposed framework showed the highest correlation coefficient of 0.77, meaning that there is a strong correlation between proposed framework and the proxy company value selected. It is concluded that the proposed framework to harmonise MAV methodologies and the emerging financial reporting requirements can be applied to estimate values for companies in the mineral industries.XL201

EFFECTIVE METHODS AND TOOLS FOR MINING APP STORE REVIEWS

Research on mining user reviews in mobile application (app) stores has noticeably advanced in the past few years. The main objective is to extract useful information that app developers can use to build more sustainable apps. In general, existing research on app store mining can be classified into three genres: classification of user feedback into different types of software maintenance requests (e.g., bug reports and feature requests), building practical tools that are readily available for developers to use, and proposing visions for enhanced mobile app stores that integrate multiple sources of user feedback to ensure app survivability. Despite these major advances, existing tools and techniques still suffer from several drawbacks. Specifically, the majority of techniques rely on the textual content of user reviews for classification. However, due to the inherently diverse and unstructured nature of user-generated online textual reviews, text-based review mining techniques often produce excessively complicated models that are prone to over-fitting. Furthermore, the majority of proposed techniques focus on extracting and classifying the functional requirements in mobile app reviews, providing a little or no support for extracting and synthesizing the non-functional requirements (NFRs) raised in user feedback (e.g., security, reliability, and usability). In terms of tool support, existing tools are still far from being adequate for practical applications. In general, there is a lack of off-the-shelf tools that can be used by researchers and practitioners to accurately mine user reviews. Motivated by these observations, in this dissertation, we explore several research directions aimed at addressing the current issues and shortcomings in app store review mining research. In particular, we introduce a novel semantically aware approach for mining and classifying functional requirements from app store reviews. This approach reduces the dimensionality of the data and enhances the predictive capabilities of the classifier. We then present a two-phase study aimed at automatically capturing the NFRs in user reviews. We also introduce MARC, a tool that enables developers to extract, classify, and summarize user reviews