Automatic classification of software artifacts in open-source applications

Comparing software artifacts to identify their similarities and differences is a task ubiquitous in software engineering. Logical-design comparison is particularly interesting, since it can serve multiple purposes. When comparing the as-intended vs. the as-implemented designs, one can evaluate implementation-to-design conformance. When comparing newer code versions against earlier ones, one may better understand the development process of the system, recognize the refactorings it has gone through and the qualities motivating them, and infer high-order patterns in its history. Given its importance, design differencing has been the subject of much research and a variety of algorithms have been developed to compare different types of software artifacts, in support of a variety of different software-engineering activities. Our team has developed two different algorithms for differencing logical-design models of object-oriented software. Both algorithms adopt a similar conceptual model of UML logical designs (as containment trees); however, one of them is heuristic whereas the other relies on a generic tree-differencing algorithm. In this paper, we describe the two approaches and we compare them on multiple versions of an open-source software system.KeywordsUMLsoftware differencingsoftware evolution

The paper presents iTrace, an Eclipse plugin that implicitly records developers' eye movements while they work on change tasks. iTrace is the first eye tracking environment that makes it possible for researchers to conduct eye tracking studies on large software systems. An overview of the design and architecture is presented along with features and usage scenarios. iTrace is designed to support a variety of eye trackers. The design is flexible enough to record eye movements on various types of software artifacts (Java code, text/html/xml documents, diagrams), as well as IDE user interface elements. The plugin has been successfully used for software traceability tasks and program comprehension tasks. iTrace is also applicable to other tasks such as code summarization and code recommendations based on developer eye movements. A short video demonstration is available at https://youtu.be/3OUnLCX4dXo.

Business process modelling is an important part of system design. When designing or redesigning a business process, stakeholders specify, negotiate, and agree on business requirements to be satisfied, including non-functional requirements that concern the quality of the business process. This thesis addresses the question of how to specify and compute the quality of a business process, given the model that stakeholders use. The motivation for this thesis is the increasing importance of the quality of business processes. Knowing the quality of specific business processes enables stakeholders to judge if these processes need improvement. Knowing the quality of the constructs of those processes (viz., events, inputs, activities, and outputs) and the way they are structured enables a more detailed analysis of their shortcomings and provides a basis for the design of improvements. The research challenge of this thesis is grounded in the assumption that: “Organisations need an appropriate means to effectively compute achievement of their goals and objectives by their business processes.” Given this challenge, the main research question on which this thesis focuses is: “Can the quality of a business process be computed quantitatively at different levels of granularity?” The research objective is: “To develop frameworks, factors, and metrics for computing non-functional requirements (quality) of business processes quantitatively at different levels of granularity.” The outcomes of this thesis are: 1) BPIMM, a language-independent business process integrating meta-model, based on the concepts of seven mainstream business process modelling languages: BPMN, EPC, RAD, UML AD, SADT, IDEF0, and IDEF3. 2) BPC-QC (Business Process Concept - Quality Computation), an approach to quality computation at the lowest level of granularity of a business process. The approach consists of: i. BPC-QEF (Business Process Concept - Quality Evaluation Framework), a language-independent generic framework and algorithm to compute the quality of the constructs of a business process: event, input, activity, and output. ii. A set of business process quality dimensions and factors. The following quality dimensions are distinguished: performance, efficiency, reliability, recoverability, permissibility, and availability. Each dimension categorises different quality aspects in terms of factors. A non-exhaustive set of sixteen quantitative factors is provided. iii. Quality metrics for each of the quality factors, to facilitate a quantitative computation of the quality of a specific construct of a business process. 3) BP-QC (Business Process - Quality Computation), an approach to compute the quality at the highest level of granularity of a business process. The approach consists of: i. BP-CQCF (Business Process - Compositional Quality Computation Framework), a language-independent generic framework and algorithm to compute the quality of a business process as a whole, given the quality of its constructs. ii. A set of generic business process modelling patterns to decompose a business process into more succinct parts, namely: sequential, parallel with synchronisation, exclusive, inclusive, simple loop, and complex loop. iii. A set of over one hundred computational formulae. For each combination of modelling pattern and a quality factor, there is a formula to compute the quality. 4) AAV (Approach to Application and Validation), an evaluation plan to evaluate BPIMM, BPC-QC and BP-QC in practice, together with expert stakeholders. The plan consists of the units of measure, a measurement model, and a case study procedure. To evaluate the applicability of the contributions of this thesis to real world business needs, four case studies have been conducted in different environments: a Dutch educational institution, a global financial institution, an international financial service provider, and a Dutch research project on crisis management. Each of these case studies concerns a different, single business process. This thesis shows that: 1) A quality computation approach can be adopted independent of a business process modelling language. 2) Quantitative quality factors can be introduced specifically for the constructs of a business process. 3) Quantitative metrics and computational formulae can be developed for specific quality factors, allowing the computation of different aspects of the quality of a business process quantitatively at different levels of granularity. 4) An evaluation plan can be developed to evaluate the applicability of the contributions of this thesis (viz., BPIMM, BPC-QC, and BP-QC). The contributions of this thesis are designed to be beneficial to the areas of business and management, requirements engineering, software engineering, and business process modelling. In the areas of requirements engineering and software engineering, these contributions are intended to help practitioners to consider non-functional requirements at the earliest stage. In the area of business process modelling, information systems, service computing, and cloud computing, the contributions can be used for quality-driven modelling, design, and redesign. To conclude, knowing the quality value of a business process at different levels of granularity provides a basis for its improvement.

This report documents the program and the outcomes of Dagstuhl Seminar 12071 ``Software Clone Management Towards Industrial Application''. Software clones are identical or similar pieces of code or design. A lot of research has been devoted to software clones. Unlike previous research, this seminar put a particular emphasis on industrial application of software clone management methods and tools and aimed at gathering concrete usage scenarios of clone management in industry, which will help to identify new industrially relevant aspects in order to shape the future research. Talks were presented by industrial participants and working groups were formed to discuss issues in clone detection, presentation, and refactoring. In addition we developed a unified conceptual model to capture clone information required to support a common notion of clone data and for interoperability to foster exchange of data among researchers and tools in practice. The main focus of current research is clones in source code -- therefore, we also looked into ways of extending our research to other types of software artifacts. Last but not least, we discussed how clone management activities may be integrated into the process of software development.

Technical debt (TD) is a concept used to describe a sub-optimal solution of a software artifact that negatively affects its comprehensibility, extendability and maintainability. As such, TD adversely affects the costs or quality associated with the artifact, which is also called interest. TD has through research been identified in all types of software artifacts, from architectural design to automated tests (Testware). However, research into testware technical debt (TTD) is limited and primarily focused on testing on lower level of system abstraction, i.e. unit-and integration tests, leaving a need for more TTD research on GUI-based testing. In this study we explore this gap in knowledge through an industrial case study at a Swedish avionics software development company. Four repositories are studied for the presence of TTD using expert interviews, semi-automated document analysis and automatic metric analysis. Results of the study provide initial support that the concept of TTD is applicable to GUI-based testware and show the presence of both TD items unique to GUI-based testware and items common to software. The implications of these results are that engineering best practices must be established for GUI-based testware to minimize TD interest.

As an important type of architectural knowledge, architectural assumptions should be well managed in projects. However, little empirical research has been conducted regarding architectural assumptions and their management in software development. In this paper, we conducted an exploratory case study with twenty-four architects to analyze architectural assumptions and their management in industry. In this study, we confirmed certain findings from our previous survey on architectural assumptions (e.g., neither the term nor the concept of architectural assumption is commonly used in industry, and stakeholders may have different understandings of the architectural assumption concept). We also got five new findings: (1) architects frequently make architectural assumptions in their work; (2) the architectural assumption concept is subjective; (3) architectural assumptions are context-dependent and have a dynamic nature (e.g., turning out to be invalid or vice versa during their lifecycle); (4) there is a connection between architectural assumptions and certain types of software artifacts (e.g., requirements and design decisions); (5) twelve architectural assumptions management activities and four benefits of managing architectural assumptions were identified.

In traditional formal concept analysis, the attributes in the formal context are considered fixed. However, in the real world data set, attributes always have different levels of granularity, correspondingly, the derived concept lattice may reveal different information and patterns. Therefore, the capability to change the level of granularity of an attribute in formal concept analysis to capture relevant patterns in data is a natural requirement. In this paper, a theoretical study has been undertaken in multi-scale formal contexts, where attributes with different levels of granularity possess different attribute values. Two types of formal concepts, i.e., object-oriented and property-oriented multi-scale concepts, are introduced and studied in detail. The collection of object-oriented concept lattices and property-oriented concept lattices can be obtained at different granularity levels of attributes. It has been shown that the set of extents in the derived concept lattices increases when we choose to use a finer level of granularity. Moreover, a corresponding bidirectional approach to concept construction(i.e., from coarser to finer and from finer to coarser, respectively) is exhibited, and some characterization theorems have been obtained.

In this paper we present a system for automatic Arabic text diacritization using three levels of analysis granularity in a layered back off manner. We build and exploit diacritized language models (LM) for each of three different levels of granularity: surface form, morphologically segmented into prefix/stem/suffix, and character level. For each of the passes, we use Viterbi search to pick the most probable diacritization per word in the input. We start with the surface form LM, followed by the morphological level, then finally we leverage the character level LM. Our system outperforms all of the published systems evaluated against the same training and test data. It achieves a 10.87% WER for complete full diacritization including lexical and syntactic diacritization, and 3.0% WER for lexical diacritization, ignoring syntactic diacritization.

A concept of hierarchical topic is proposed for multi-document automatic summarization task, which used multi-layer topic tree structure to represent the text set. Each node in the topic tree represent specific topic and contains multiple similar sentences in the text set. The hierarchical topic structure may describe accurately the similarity between sentences at different levels of granularity. Therefore it can reflect the real content of the text set than single layer topic set. And can be used to find the important sentences in the important topic which can compose the summary of the text set. Concretely, a series of algorithms including building hierarchical topic tree, key sentences extraction based on hierarchical topic tree and summarization generation are proposed. The capability of summarization system is testified by sets of experiments and shows good result.

Data warehousing is widely used in industry for reporting and analysis of huge volumes of data at different levels of detail. In general, data warehouses use standard dimensional schema designs to organize their data. However, current data warehousing schema designs fall short in their ability to model the multi-granular data found in various real-world application domains. For example, modern farm equipment in a field produces massive amounts of data at different levels of granularity that has to be stored and queried. A study of the commonly used data warehousing schemas exposes the limitation that the schema designs are intended to simply store data at the same single level of granularity. This paper on the other hand, presents several extended dimensional data warehousing schema design alternatives to store both detail and aggregated data at different levels of granularity. The paper presents three solutions to design the time dimension tables and four solutions to design the fact tables. Moreover, each of these solutions is evaluated in different combinations of the time dimension and the fact tables based on a real world farming case study.KeywordsMulti-granular datadata warehousingdata warehousing schema design

Geo‐SOMis a useful geovisualization technique for revealing patterns in spatial data, but is ineffective in supporting interactive exploration of patterns hidden in differentGeo‐SOMsizes. Based on the divide and group principle in geovisualization, the article proposes a new methodology that combinesGeo‐SOMand hierarchical clustering to tackle this problem.Geo‐SOMwas used to “divide” the dataset into several homogeneous subsets; hierarchical clustering was then used to “group” neighboring homogeneous subsets for pattern exploration in different levels of granularity, thus permitting exploration of patterns at multiple scales. An artificial dataset was used for validating the method's effectiveness. As a case study, the rush hour motorcycle flow data inTaipeiCity,Taiwan were analyzed. Compared with the best result generated solely byGeo‐SOM, the proposed method performed better in capturing the homogeneous zones in the artificial dataset. For the case study, the proposed method discovered six clusters with unique data and spatial patterns at different levels of granularity, while the originalGeo‐SOMonly identified two. Among the four hierarchical clustering methods,Ward's clustering performed the best in pattern discovery. The results demonstrated the effectiveness of the approach in visually and interactively exploring data and spatial patterns in geospatial data.

Due to the rapid development of social media networks, as well as the recent advances on smartphone technologies, users stopped being only consumers and became data producers. It enabled a new form of sensing, engaging a variety of studies using Location-Based Social Networks (LBSN) data. For instance, in device-to-device(D2D) communication systems, the user location is required to make mobile data offloading possible. However, getting the right location is a challenging task, and the analyses of LBSN datasets provide large-scale studies at a low-cost. On the other hand, depending the the level of granularity used on the analyses, it may result in the success or failure of the prediction. Therefore, in this paper, we show the importance of combining the different levels of granularities for studying user behavior in order to obtain a robuster analysis.

The exploding number of computational models produced by Systems Biologists over the last years is an invitation to structure and exploit this new wealth of information. Researchers would like to trace models relevant to specific scientific questions, to explore their biological content, to align and combine them, and to match them with experimental data. To automate these processes, it is essential to consider semantic annotations, which describe their biological meaning. As a prerequisite for a wide range of computational methods, we propose general and flexible similarity measures for Systems Biology models computed from semantic annotations. By using these measures and a large extensible ontology, we implement a platform that can retrieve, cluster, and align Systems Biology models and experimental data sets. At present, its major application is the search for relevant models in the BioModels Database, starting from initial models, data sets, or lists of biological concepts. Beyond similarity searches, the representation of models by semantic feature vectors may pave the way for visualisation, exploration, and statistical analysis of large collections of models and corresponding data.

This paper introduces the concept of granularity into routine dynamics studies. To establish levels of granularity we develop a phenomenological perspective on action, the central category of routine dynamics studies. By conducting an extensive literature review we show that routine dynamics scholars have at least unconsciously applied diverging levels of granularity in their empirical studies. We argue that side-stepping questions of explicitly addressing granularity significantly impedes the comparability of studies since different levels of granularity bring different aspects of performing and patterning processes into focus. Following this, we develop a methodological framework that allows scholars to establish and report on the level of granularity in their study. Finally, we sketch out some implications of taking granularity seriously for writing up research on routine dynamics.

This study explores the classification of glass artifacts based on their chemical composition. Using the stratified chi-square test method, the correlation between the chemical characteristics of glass artifacts and their susceptibility to weathering was analyzed. A decision tree model was constructed to predict and analyze the types of glass artifacts. To further study the types of glass artifacts, factor analysis was employed to reduce the dimensionality of the data, simplifying the data structure. Based on the reduced data, the K-means clustering algorithm was used to further classify the glass artifacts into three subcategories.