Test overlay in an emerging software product line – An industrial case study

ContextIn large software organizations with a product line development approach, system test planning and scope selection is a complex task. Due to repeated testing: across different testing levels, over time (test for regression) as well as of different variants, the risk of redundant testing is large as well as the risk of overlooking important tests, hidden by the huge amount of possible tests.AimsThis study assesses the amount and type of overlaid manual testing across feature, integration and system test in such context, it explores the causes of potential redundancy and elaborates on how to provide decision support in terms of visualization for the purpose of avoiding redundancy.MethodAn in-depth case study was launched including both qualitative and quantitative observations.ResultsA high degree of test overlay is identified originating from distributed test responsibilities, poor documentation and structure of test cases, parallel work and insufficient delta analysis. The amount of test overlay depends on which level of abstraction is studied.ConclusionsAvoiding redundancy requires tool support, e.g. visualization of test design coverage, test execution progress, priorities of coverage items as well as visualized priorities of variants to support test case selection.     

User-centered design in universal design resources?

Studies have revealed usability problems with universal design resources (UDRs). In this paper, four UDR development cases are reviewed (Section 508 standards, Web accessibility guidelines, the British Standard on managing inclusive design, and Irish guidelines on public access terminals). Evidence of a user-centered design approach was found in only one case. The needs of people making universally usable products and services in industry are discussed in the context of the use of UDRs and results of organizational research studies. Nine recommendations are made on the development of user-centered UDRs and the setup and management of accessibility teams in organizations.     

The development of ergonomics data for health-building design guidance∗

Abstract

Changes in policy and resources result in health-care systems which are constantly evolving. The evolution is reflected in physical and functional changes in health-building designs.

Building design guidance must be capable of accommodating these changes without losing its validity or usefulness. This paper discusses the development of an ergonomics (i.e. user oriented) data bank, linked to a checklist of component parts (i.e. items of furniture and equipment), whose effective and efficient use and interrelationship determines the form and planning of an effective and efficient health building.

The developed data system is seen as an effective tool for quality control, which can be applied at the drawing-board stage in health-building design, and which has previously not been available.     

Modular product design with grouping genetic algorithm—a case study

Modular products are products that fulfill various functions through the combination of distinct modules. These detachable modules are constructed both according to the maximum physical and functional relations among components and maximizing the similarity of specifically modular driving forces. Accordingly, a non-linear programming is proposed to identify separable modules and simultaneously optimize the number of modules. This paper presents a systematic approach to accomplish modular product design in four major phases. Phase 1 is by means of functional and physical interaction analysis to format a component-to-component correlation matrix. Phase 2 is the exploration of design requirements to evaluate the relative importance of each modular driver. In phase 3, non-linear programming is used to formulate the objective function. In the final phase, a heuristic grouping genetic algorithm is adopted to search for the optimal or near-optimal modular architecture. This process and its application are illustrated by a real case of an electrical consumer product provided by an Original Design Manufacturer. The results demonstrate that the designer could direct a new approach to establish product modules according to the relative importance of modular drivers and the interaction among components.     

Research on industrial product–service configuration driven by value demands based on ontology modeling

It has become an important trend in the manufacturing industry that service is used to enhance the competitiveness of businesses as well as an important source of values. Aiming to extend the achievements of product configuration in manufacturing industry to service industry, an ontology-based product–service configuration approach is presented in this paper. Firstly, value attributes of product–service are defined based on the analysis of customer demands. And the demand cluster method is proposed to identify value demands of customers. Secondly, the modular system of product–service is established which is the basis of building product–service ontology. Thirdly, the product–service configuration method based on ontology modeling is put forward. Finally, the proposed approach to product–service configuration is demonstrated by an example of configuring service packages of civil aircraft materials.     

Constraints for the design of variability-intensive service-oriented reference architectures – An industrial case study

ContextService-oriented architecture has become a widely used concept in software industry. However, we currently lack support for designing variability-intensive service-oriented systems. Such systems could be used in different environments, without the need to design them from scratch. To support the design of variability-intensive service-oriented systems, reference architectures that facilitate variability in instantiated service-oriented architectures can help.ObjectiveThe design of variability-intensive service-oriented reference architectures is subject to specific constraints. Architects need to know these constraints when designing such reference architectures. Our objective is to identify these constraints.MethodAn exploratory case study was performed in the context of local e-government in the Netherlands to study constraints from the perspective of (a) the users of a variability-intensive service-oriented system (municipalities that implement national laws), and (b) the implementing organizations (software vendors). We collected data through interviews with representatives from five organizations, document analyses and expert meetings.ResultsWe identified ten constraints (e.g., organizational constraints, integration-related constraints) which affect the process of designing reference architectures for variability-intensive service-oriented systems. Also, we identified how stakeholders are affected by these constraints, and how constraints are specific to the case study domain.ConclusionsOur results help design variability-intensive service-oriented reference architectures. Furthermore, our results can be used to define processes to design such reference architectures.     

μ-synthesis in H-infinity loop-shaping design

H∞控制理论中的回路成形设计和μ综合都已经是定型的设计方法．最近有文献提出一种将这两种设计方法结合起来处理弱阻尼谐振模态参数摄动的新方法．但是实际设计表明,二者的结合并没有达到预期的效果．本文分析指出,回路成形本质上是一种鲁棒稳定性设计,其H∞范数指标的逆就是系统的稳定裕度．而μ综合只是一种鲁棒性能的设计工具．μ综合与回路成形结合只是反映在稳定裕度上,而并不影响设计所允许的摄动大小．所以在回路成形设计中没有必要再加进μ综合法．文中附有算例．     

Parameter identification in strobed tracer-kinetic processes∗

A technique of quasilinearization is developed and applied to the problem of identifying the unknown parameters in strobed tracer-kinetic compartmental systems of known topology. The method has particular value in finding functional relations between elements of physiological processes that function in a fundamentally rhythmic or cyclic manner.     

Factors affecting ambulatory heart rate in industrial workers†

The influence of several factors on the heart-rate (HR) response to tasks performed during regular work has been evaluated in a study population of 1654 male factory employees in Israel. Each worker was monitored for approximately one hour with an ambulatory electrocardiogram. The percentage change from resting HR decreased with increasing age and, as expected, was lower in sedentary workers than in manual workers. A highly significant negative correlation between the HR response and both systolic and diastolic blood pressure was found in the manual workers only. In further multiple regression analysis, after controlling for age, relative weight, smoking status, resting HR and the presence of abnormalities on the resting ECG, the association persisted for systolic BP only. Among young workers, both smoking and relative body weight were significantly associated with a higher HR response to work. Those with ECG abnormalities had lower HR response than those with normal ECGs, but not significantly so. These findings indicate that for roughly equivalent tasks and levels of resting HR, the HR response to regular work is influenced by several constitutional and behavioural factors. It may therefore be important to consider these factors when assigning workers to tasks involving strenuous effort.     

Grading in interaction design education using design practitioners’ conceptions of process quality

The designed product is often assessed in interaction design education, but there are also courses that focus on learning the design process. It is then necessary to develop criteria for grading in such courses. To make a successful transfer from theory to practice, students also need to learn the criteria practitioners use, rather than the criteria that academically oriented teachers use. To do this, one approach is to align criteria with the conceptions practicing interaction designers have of process quality in design. Therefore, the research questions for this study are what those conceptions are, and how they can be utilized in grading criteria for interaction design projects in education. Interviews were made with 10 interaction designers. The interviews were qualitatively analyzed. The results demonstrate that practicing interaction designers conceptualize the quality of the design process in three ways: it is good if established methods are used and the design is managed within resource constraints, and within organizational and technological limitations, while also meeting stated objectives; it is even better if the design has a thought-through rationale; and ideally, the design should also be inspirational. These conceptions were transferred to points on a criteria-referenced grading scale which was used to develop course specific grading criteria. The criteria were evaluated in terms of comprehensibility and reliability. The evaluation showed that most of the students who also attended lectures understood the criteria. A high and significant covariation and a high level of agreement between the two teachers who graded the projects were shown. Further, the developed criteria should be generalizable to other process-centered interaction design courses and to assessment in other design disciplines.     

Do you believe in the advantage of expert systems in industrial ergonomics?

Reasons for reservations about accepting the recommendations of industrial ergonomics are first explored. A knowledge deficiency is ascertained which results in a general dependency on ergonomic experts. The experts, however, are rarely able to communicate their knowledge in a form applicable by a practitioner. The development and employment of expert systems suitable for use in work design problems are proposed to resolve this dilemma. The question of whether an interest in expert systems for industrial ergonomics can be assumed is considered. The necessary conditions for the successful development and introduction of expert systems for industrial ergonomics are derived. The extent to which currently available expert system technology can support the typical procedures in industrial ergonomics is subsequently examined.     

Perceived Causes of Difficulty in Work Situations∗

Examples of difficult work situations were collected from five different types of jobs by interviewing panels of employees a number of times. The situational causes of difficulty, as perceived by the employees, were classified into a number of ' difficulty factors'. The importance of a factor for the difficulty of a certain job was measured in terms of its frequency in the interview records. Among three broad classes of factors—decision-making, interpersonal contacts, and time-and-energy resources—the decision-making factors had the highest frequency in all five jobs, but the pattern of individual factors differed among jobs. Correlation measures were also obtained, between the intensity of each factor and perceived difficulty, and between the sum of factor scores and perceived difficulty.     

A free lunch in linearized experimental design?

The No Free Lunch (NFL) theorems state that no single optimization algorithm is ideally suited for all objective functions and, conversely, that no single objective function is ideally suited for all optimization algorithms. This paper examines the influence of the NFL theorems on linearized statistical experimental design (SED). We consider four design algorithms with three different design objective functions to examine their interdependency. As a foundation for the study, we consider experimental designs for fitting ellipses to data, a problem pertinent to the study of transverse isotropy in many disciplines. Surprisingly, we find that the quality of optimized experiments, and the computational efficiency of their optimization, is generally independent of the criterion-algorithm pairing. We discuss differences in the performance of each design algorithm, providing a guideline for selecting design algorithms for other problems. As a by-product we demonstrate and discuss the principle of diminishing returns in SED, namely, that the value of experimental design decreases with experiment size. Another outcome of this study is a simple rule-of-thumb for prescribing optimal experiments for ellipse fitting, which bypasses the computational expense of SED. This is used to define a template for optimizing survey designs, under simple assumptions, for Amplitude Variations with Azimuth and Offset (AVAZ) seismics in the specialized problem of fracture characterization, such as is of interest in the petroleum industry. Finally, we discuss the scope of our conclusions for the NFL theorems as they apply to nonlinear and Bayesian SED.