A Game-theoretic approach to analyze interacting actors in GRL goal models

Goal-oriented requirements engineering aims to capture desired goals and strategies of relevant stakeholders during early requirements engineering stages, using goal models. Goal-oriented modeling techniques support the analysis of system requirements (especially non-functional ones) from an operationalization perspective, through the evaluation of alternative design options. However, conflicts and undesirable interactions between requirements produced from goals are inevitable, especially as stakeholders often aim for different objectives. In this paper, we propose an approach based on game theory and the Goal-oriented Requirement Language (GRL) to reconcile interacting stakeholders (captured as GRL actors), leading to reasonable trade-offs. This approach consists in building a payoff bimatrix that considers all actor’s valid GRL strategies, and computing its Nash equilibrium. Furthermore, we use two optimization techniques to reduce the size of the payoff bimatrix, hence reducing the computational cost of the Nash equilibrium. The approach goes beyond existing work by supporting nonzero-sum games, multiple alternatives, and inter-actor dependencies. We demonstrate the applicability of our game-theoretic modeling and analysis approach using a running example and two GRL models from the literature, with positive results on feasibility and applicability, including performance results.

     

An empirical approach toward the resolution of conflicts in goal-oriented models

One significant problem requirements engineers have to cope with is the management of unclear requirements, ambiguities, and conflicts that may arise between stakeholders. Such issues may be desirable since they may allow for further elicitation of requirements that would have been missed otherwise. Goal models capture the objectives and other intentions of different stakeholders, together with their relationships. They can be used to refine unclear requirements and to detect conflicts and ambiguities early during model validation. However, resolving such ambiguities and conflicts is key for the successful implementation of the goal models. In this paper, we propose a novel approach to validate models in the Goal-oriented Requirement Language and resolve conflicts between the perspectives of intervening stakeholders (and especially between stakeholders of a given group). Our approach is based on a statistical analysis of empirical data that we collect from surveys designed for each group of stakeholders. We apply concept analysis in order to fix goal-model artifacts that are subject to conflict. We illustrate our approach using a case study of a goal model describing the involvement of undergraduate students in university research activities.     

The treatment of ureteroceles complicated by calculi

In a series of 13 adults with calculi in ureteroceles, 10 cases underwent endoscopic meatotomy associated with endoscopic lithotripsy. In 2 bulky ureteroceles with calculi, the authors performed excision of the ureterocele and reimplantation of the ureter. In one case, the authors successfully performed extracorporeal lithotripsy. The authors obtained good results in all cases. Endoscopic meatotomy with lithotripsy is a very useful procedure for treatment of small or medium sized ureteroceles with calculi in adults.     

Environmentally Friendly Graphene Inks for Touch Screen Sensors

Graphene-based materials have attracted significant attention in many technological fields, but scaling up graphene-based technologies still faces substantial challenges. High-throughput top-down methods generally require hazardous, toxic, and high-boiling-point solvents. Here, an efficient and inexpensive strategy is proposed to produce graphene dispersions by liquid-phase exfoliation (LPE) through a combination of shear-mixing (SM) and tip sonication (TS) techniques, yielding highly concentrated graphene inks compatible with spray coating. The quality of graphene flakes (e.g., lateral size and thickness) and their concentration in the dispersions are compared using different spectroscopic and microscopy techniques. Several approaches (individual SM and TS, and their combination) are tested in three solvents (N-methyl-2-pyrrolidone, dimethylformamide, and cyrene). Interestingly, the combination of SM and TS in cyrene yields high-quality graphene dispersions, overcoming the environmental issues linked to the other two solvents. Starting from the cyrene dispersion, a graphene-based ink is prepared to spray-coat flexible electrodes and assemble a touch screen prototype. The electrodes feature a low sheet resistance (290 Ω □⁻¹) and high optical transmittance (78%), which provide the prototype with a high signal-to-noise ratio (14 dB) and multi-touch functionality (up to four simultaneous touches). These results illustrate a potential pathway toward the integration of LPE-graphene in commercial flexible electronics.     

Malware Detection Using Decision Tree Based SVM Classifier for IoT

The development in Information and Communication Technology has led to the evolution of new computing and communication environment. Technological revolution with Internet of Things (IoTs) has developed various applications in almost all domains from health care, education to entertainment with sensors and smart devices. One of the subsets of IoT is Internet of Medical things (IoMT) which connects medical devices, hardware and software applications through internet. IoMT enables secure wireless communication over the Internet to allow efficient analysis of medical data. With these smart advancements and exploitation of smart IoT devices in health care technology there increases threat and malware attacks during transmission of highly confidential medical data. This work proposes a scheme by integrating machine learning approach and block chain technology to detect malware during data transmission in IoMT. The proposed Machine Learning based Block Chain Technology malware detection scheme (MLBCT-Mdetect) is implemented in three steps namely: feature extraction, Classification and blockchain. Feature extraction is performed by calculating the weight of each feature and reduces the features with less weight. Support Vector Machine classifier is employed in the second step to classify the malware and benign nodes. Furthermore, third step uses blockchain to store details of the selected features which eventually improves the detection of malware with significant improvement in speed and accuracy. ML-BCT-Mdetect achieves higher accuracy with low false positive rate and higher True positive rate.     

The possible role of the pre-exponential factor in explaining the increased reaction rates observed during the microwave synthesis of titanium carbide

Reaction rates observed during the microwave synthesis of titanium carbide powder via the carbothermal reduction of the oxide are more than three times faster than those observed during conventional processing at the same temperature. Although not dissimilar to other reports of microwave effects in the literature, this result is of interest because the microwave heating mechanism is quite different compared to work using ionic ceramics. The initial powder mix consisted of low dielectric loss titania mixed intimately with very fine carbon black powder. It is the latter phase which couples with the microwaves via a conventional ohmic dissipation mechanism. Calculations have shown that the faster diffusion rates might be explained by an increase in the Arrhenius pre-exponential factor A, with no change in the activation energy.     

A questionnaire-based survey methodology for systematically validating goal-oriented models

Goal models represent interests, intentions, and strategies of different stakeholders. Reasoning about the goals of a system unavoidably involves the transformation of unclear stakeholder requirements into goal-oriented models. The ability to validate goal models would support the early detection of unclear requirements, ambiguities, and conflicts. In this paper, we propose a novel validation approach based on the Goal-oriented Requirement Language (GRL) to check the correctness of GRL goal models through statistical analyses of data collected from generated questionnaires. System stakeholders (e.g., customers, shareholders, and managers) may have different objectives, interests, and priorities. Stakeholder conflicts arise when the needs of some group of stakeholder compromise the expectations of some other group(s) of stakeholders. Our proposed approach allows for early detection of potential conflicts amongst intervening stakeholders of the system. In order to illustrate and demonstrate the feasibility of the approach, we apply it to a case study of a GRL model describing the fostering of the relationship between the university and its alumni. The approach brings unique benefits over the state of the art and is complementary to existing validation approaches.     

Rapid Exponential Stabilization of a 1‐D Transmission Wave Equation with In‐domain Anti‐damping

We consider the problem of pointwise stabilization of a one‐dimensional wave equation with an internal spatially varying anti‐damping term. We design a feedback law based on the backstepping method and prove exponential stability of the closed‐loop system with a desired decay rate.     

A use case driven approach to game modeling

Requirements Engineering - With the increase in market needs, game development teams are facing a high demand of creating new games every year. Although several methodologies and tools were...     

Surface properties of methyl methacrylate hardened hybrid poplar wood

The surface properties of fast‐growing poplar clones and their methyl methacrylate (MMA)‐hardened wood related to potential end uses were investigated. Samples from 24 trees of six hybrid poplar clones in one plantation in Quebec were hardened with MMA. The effects of MMA hardening on the density and surface properties were studied. Scanning electron microscopy and Fourier transform infrared analysis showed that filling the voids in the wood structure was the main hardening mechanism. The incorporation of the polymer increased the density of all of the poplar clones by 120–160%. The Janka hardness was found to be 2.5–4 times higher in the treated poplar wood than in the untreated poplar wood. The treated wood also exhibited superior abrasion resistance compared to the controls. The results indicate that hardening with MMA improved the surface properties and that the MMA‐hardened wood was comparable to natural hardwoods. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012