Using empirical studies to mitigate symbol overload in iStar extensions

UID/CEC/04516/2019Modelling languages are frequently extended to include new constructs to be used together with the original syntax. New constructs may be proposed by adding textual information, such as UML stereotypes, or by creating new graphical representations. Thus, these new symbols need to be expressive and proposed in a careful way to increase the extension’s adoption. A method to create symbols for the original constructs of a modelling language was proposed and has been used to create the symbols when a new modelling language is designed. We argue this method can be used to recommend new symbols for the extension’s constructs. However, it is necessary to make some adjustments since the new symbols will be used with the existing constructs of the modelling language original syntax. In this paper, we analyse the usage of this adapted method to propose symbols to mitigate the occurrence of overloaded symbols in the existing iStar extensions. We analysed the existing iStar extensions in an SLR and identified the occurrence of symbol overload among the existing constructs. We identified a set of fifteen overloaded symbols in existing iStar extensions. We used these concepts with symbol overload in a multi-stage experiment that involved users in the visual notation design process. The study involved 262 participants, and its results revealed that most of the new graphical representations were better than those proposed by the extensions, with regard to semantic transparency. Thus, the new representations can be used to mitigate this kind of conflict in iStar extensions. Our results suggest that next extension efforts should consider user-generated notation design techniques in order to increase the semantic transparency.authorsversionpublishe

Formal verification of the extension of iStar to support Big data projects

Identifying all the right requirements is indispensable for the success of anysystem. These requirements need to be engineered with precision in the earlyphases. Principally, late corrections costs are estimated to be more than 200times as much as corrections during requirements engineering (RE). EspeciallyBig data area, it becomes more and more crucial due to its importance andcharacteristics. In fact, and after literature analyzing, we note that currentsRE methods do not support the elicitation of Big data projects requirements. Inthis study, we propose the BiStar novel method as extension of iStar to under-take some Big data characteristics such as (volume, variety ...etc). As a firststep, we identify some missing concepts that currents requirements engineeringmethods do not support. Next, BiStar, an extension of iStar is developed totake into account Big data specifics characteristics while dealing with require-ments. In order to ensure the integrity property of BiStar, formal proofs weremade, we perform a bigraph based description on iStar and BiStar. Finally, anapplication is conducted on iStar and BiStar for the same illustrative scenario.The BiStar shows important results to be more suitable for eliciting Big dataprojects requirements

A social and technical sustainability requirements catalogue

Isabel Sofia Brito is a Coordinator Professor at Polytechnic Institute of Beja, Portugal, and a member of the Centre of Technology and Systems (CTS-UNINOVA). Her main research interests are Requirements Engineering and Sustainability Requirements, Model and Data-Driven Development, Multi-Criteria Decision Making and, Big Data. She has published several papers on these topics. She has been involved in several national and international research projects (e.g., COMPETISOF, Petri-Rig, U-Bike Project). Currently, she is involved in the international applied research project HIBA—Hub Iberia Agrotech, an initiative funded by Digital Innovation Hub (DIH) and “Portugal INCoDe.2030”. She is or was involved as organiser, conference chair and program committee member in several international conferences (e.g., IEEE RE, ACM SAC, CISTI, QUATIC, CIbSE, ICT4S) and in several smaller and regional ones. Publisher Copyright: © 2022 The Author(s)Climate change calls for action from all sectors of our global economy, including ICT. Therefore, it is important to change the way we develop software to address the challenges posed by sustainability. Our goal is to contribute with a reusable sustainability requirements catalogue that helps developers be aware of sustainability-related properties worth considering during software development. The information for this catalogue was gathered via a systematic mapping study, whose results were synthesised in feature models and then modelled using iStar for a more expressive and configurable representation. A qualitative evaluation of the catalogue's readability, interest, utility, and usefulness by 50 participants from the domain, showed that around 79% of the respondents found the catalogue “Good” or “Very Good”. However, more than 5% of the expert participants found weaknesses regarding most of the evaluated questions and around 25% are neutral in their overall evaluation. This led us to evolve the initial version of the catalogue for the social and technical dimensions of sustainability to improve its completeness and usefulness. This is achieved by aligning the information gathered in the systematic mapping study with the well-established quality model of the ISO/IEC 25010:2011, as we expect most of the experts are familiar with those qualities and respective hierarchies. During this process, we found information that led us to propose two additional qualities that were not covered by the ISO standard: fairness and legislation. We applied this evolved version of the catalogue to the U-Bike project comparing the requirements elicited without the catalogue with those identified using the catalogue. The result suggests that new sustainability requirements were worth considering from a sustainability point of view, supporting the usefulness of the catalogue.publishersversionpublishe

Numerical study on parametrical design of long shrouded contra-rotating propulsion system in hovering

The parametrical study of Shrouded Contra-rotating Rotor was done in this paper based on 2D axisymmetric simulations. The calculations were made with an actuator disk as double rotor model. It objects to explore and quantify the effects of different shroud geometry parameters mainly using the performance of power loading (PL), which could evaluate the whole propulsion system capability as 5 Newton total thrust generation for hover demand. The numerical results show that: The increase of nozzle radius is desired but limited by the flow separation, its optimal design is around 1.15 times rotor radius, the viscosity effects greatly constraint the influence of nozzle shape, the divergent angle around 10.5° performs best for any chosen nozzle length; The parameters of inlet such as leading edge curvature, radius and internal shape do not affect thrust greatly but play an important role in pressure distribution which could produce most part of shroud thrust, they should be chosen according to the reduction of adverse pressure gradients to avoid the risk of boundary separation

Human-in-the-Loop Operations over Time Delay: NASA Analog Missions Lessons Learned

Teams at NASA have conducted studies of time-delayed communications as it effects human exploration. In October 2012, the Advanced Exploration Systems (AES) Analog Missions project conducted a Technical Interchange Meeting (TIM) with the primary stakeholders to share information and experiences of studying time delay, to build a coherent picture of how studies are covering the problem domain, and to determine possible forward plans (including how to best communicate study results and lessons learned, how to inform future studies and mission plans, and how to drive potential development efforts). This initial meeting s participants included personnel from multiple NASA centers (HQ, JSC, KSC, ARC, and JPL), academia, and ESA. It included all of the known studies, analog missions, and tests of time delayed communications dating back to the Apollo missions including NASA Extreme Environment Mission Operations (NEEMO), Desert Research and Technology Studies (DRATS/RATS), International Space Station Test-bed for Analog Research (ISTAR), Pavilion Lake Research Project (PLRP), Mars 520, JPL Mars Orbiters/Rovers, Advanced Mission Operations (AMO), Devon Island analog missions, and Apollo experiences. Additionally, the meeting attempted to capture all of the various functional perspectives via presentations by disciplines including mission operations (flight director and mission planning), communications, crew, Capcom, Extra-Vehicular Activity (EVA), Behavioral Health and Performance (BHP), Medical/Surgeon, Science, Education and Public Outreach (EPO), and data management. The paper summarizes the descriptions and results from each of the activities discussed at the TIM and includes several recommendations captured in the meeting for dealing with time delay in human exploration along with recommendations for future development and studies to address this issue

A Sustainability Catalogue for Software Modelling

Sustainable development is the development that meets the needs of the present without compromising the needs of our future generations. It covers five different dimensions: environmental, economic, social, technical, and individual. Such dimensions are also of interest for software. For example, memory and power efficiency have an impact on the environmental dimension, the reduction of costs in software development and evolution relates to the economic dimension, the use of software for general improvement of people’s lives affects the social dimension, the software’s ability to cooperate with other systems impacts the technical dimension, and the improvement of well-being of individuals relates to the individual dimension. These various dimensions and their properties impact on each other and on the base requirements of a system. Therefore, well-informed design decisions require improved support to reason on such intra- and inter-relationships and impacts, early in development. The objective of this dissertation is to propose a catalog of sustainability requirements for later reuse during the software development process. The envisioned solution involves using requirement engineering activities to address sustainability in the early stages of the software development. The first step towards a solution was to perform a (agile) systematic mapping study in order to gain a complete and profound knowledge about the existing sustainability and requirement engineering techniques. This study was the base of our work. Our final artifact is a sustainability catalogue. This catalogue addresses four out of the five dimensions of sustainability, as well as their qualities and relationships. We did not treat the individual dimension, for sake of simplicity and time constraints, although we consider that some of its properties are included in the social dimension. The catalogue was developed using the iStar framework, and it was implemented in the piStar Tool. Such catalogue offers a generic approach that can be instantiated for particular application domains, and for any combination of dimensions. Hence, this work will contribute to the field of sustainable software development

An extension of iStar for Machine Learning requirements by following the PRISE methodology

The rise of Artificial Intelligence (AI) and Deep Learning has led to Machine Learning (ML) becoming a common practice in academia and enterprise. However, a successful ML project requires deep domain knowledge as well as expertise in a plethora of algorithms and data processing techniques. This leads to a stronger dependency and need for communication between developers and stakeholders where numerous requirements come into play. More specifically, in addition to functional requirements such as the output of the model (e.g. classification, clustering or regression), ML projects need to pay special attention to a number of non-functional and quality aspects particular to ML. These include explainability, noise robustness or equity among others. Failure to identify and consider these aspects will lead to inadequate algorithm selection and the failure of the project. In this sense, capturing ML requirements becomes critical. Unfortunately, there is currently an absence of ML requirements modeling approaches. Therefore, in this paper we present the first i* extension for capturing ML requirements and apply it to two real-world projects. Our study covers two main objectives for ML requirements: (i) allows domain experts to specify objectives and quality aspects to be met by the ML solution, and (ii) facilitates the selection and justification of the most adequate ML approaches. Our case studies show that our work enables better ML algorithm selection, preprocessing implementation tailored to each algorithm, and aids in identifying missing data. In addition, they also demonstrate the flexibility of our study to adapt to different domains.This work has been co-funded by the AETHER-UA project (PID2020-112540RB-C43), a smart data holistic approach for context-aware data analytics: smarter machine learning for business modeling and analytics, funded by the Spanish Ministry of Science and Innovation. And the BALLADEER (PROMETEO/2021/088) project, a Big Data analytical platform for the diagnosis and treatment of Attention Deficit Hyperactivity Disorder (ADHD) featuring extended reality, funded by the Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital (Generalitat Valenciana). A. Reina-Reina (I-PI 13/20) hold Industrial PhD Grants co-funded by the University of Alicante and the Lucentia Lab Spin-off Company

A Sustainability-Driven Approach for Agile Software Requirements

The SDGs (sustainable development goals) demand for the involvement of all sectors of our society, from industry to academia. Therefore, the race towards sustainability has become increasingly more important and widely covered. Sustainability involves five different dimensions: environmental, economic, social, technical and individual. These dimensions are also of interest for software development since they have an impact not only on each other but also on the base requirements of a system. Therefore, well-informed design decisions require improved support to reason on such intra- and inter-relationships and impacts, early in the development. We are interested in reasoning about these relationships in an agile context where user stories play a major role, but do not handle sustainability requirements in a methodical way. For this purpose, our first step was to understand how developers from the agile community handled sustainability. The second step was to perform a systematic mapping study where we furthered our understanding of sustainability, and software development with agile methodologies. With this study we also gained awareness concerning any approaches that have been proposed regarding the integration of sustainability in an agile context. This study is the foundation for the third part of our work: a solution that consists in extending and adapting an existing catalogue of sustainability requirements into a catalogue of sustainability user stories for later reuse during the early stages of an agile software development process. We validated the approach with a case study (U-Bike) and performed an online survey for qualitative evaluation of the proposed approach.Os ODS (objetivos de desenvolvimento sustentável) exigem o envolvimento de todos os setores da nossa sociedade, da indústria à academia. Por isso, a corrida pela sustentabilidade tem se tornado cada vez mais importante e amplamente divulgada. A sustentabilidade envolve cinco dimensões diferentes: ambiental, econômica, social, técnica e individual. Essas dimensões também são de interesse para o desenvolvimento de software, pois impactam não apenas umas nas outras, mas também nos requisitos básicos de um sistema. Portanto, decisões de projeto bem informadas requerem suporte aprimorado para raciocinar sobre tais relacionamentos e impactos intra e inter-relacionados, logo no início do desenvolvimento. Estamos interessados em raciocinar sobre esses relacionamentos em um contexto ágil, onde as user stories desempenham um papel importante, mas não tratam os requisitos de sustentabilidade de maneira metódica. Para isso, nosso primeiro passo foi entender como os desenvolvedores da comunidade ágil lidavam com a sustentabilidade. A segunda etapa foi realizar um estudo de mapeamento sistemático onde ampliamos nosso entendimento sobre sustentabilidade e desenvolvimento de software com metodologias ágeis. Com este estudo também tomamos conhecimento de quaisquer abordagens que tenham sido propostas em relação à integração da sustentabilidade em um contexto ágil. Este estudo é a base para a terceira parte do nosso trabalho: uma solução que consiste em estender e adaptar um catálogo existente de requisitos de sustentabilidade em um catálogo de user stories de sustentabilidade para posterior reutilização durante os estágios iniciais de um processo de desenvolvimento ágil de software. Validamos a abordagem com um estudo de caso (U-Bike) e realizamos uma pesquisa online para avaliação qualitativa da abordagem proposta

Design Configuration of a Generation Next Main Battle Tank for Future Combat

The future combat scenario will undergo a sea change as compared to the conventional and un-conventional warfare employed by the traditional armies and non-state actors. In such a scenario, the main battle tank which serves as a game changer during these conflicts has to face the dilemma whether its design should be either evolutionary or revolutionary. To determine the basis of selecting the right type of design based on the above, the broad parameters that define the configuration namely number of crew, weight, armament system, survivability, operating range, transportability, tactical mobility, trafficability, intelligence - surveillance - target acquisition - reconnaissance (ISTAR), system modularity and theatre of operation have been considered. Taking these parameters into account, this study evaluates both the evolutionary and revolutionary design configurations for a generation next main battle tank. Finally, from the outcome of this study it is observed that the revolutionary design approach not only fares better compared to the evolutionary approach, but also possess ease of adaptiveness as an universal combat weapon platform

You Want to be an IRB Community Member... Now What? A resource manual in two parts

https://oprs.usc.edu/files/2013/01/community_member_web.pd