RFOS - Repository of Faculty of Organizational Sciences Univ. of Belgrade
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A Smart City IoT Crowdsensing System Based on Data Streaming Architecture
No full textThe subject of this paper is data streaming in IoT crowdsensing systems. The goal of this paper is to present a way of designing a scalable IoT crowdsensing system that enables design of various business models for smart city projects. The system designed in such a way is capable of handling an increasing number of users while maintaining acceptable performance. Performance of the system can be measured in response latency, which allows for real-time tracking of crowdsensing parameters. The first part of the paper deals with data streaming concepts and software solutions, with a particular focus on Apache Kafka. The second part presents the designed system for crowdsensing in smart city environments. The designed system allows for use of mobile and Arduino devices as input data for the Kafka cloud cluster in order to provide crowdsourcing insights in real-time. The primary way that users can utilize these insights is through a web or mobile application, where various data visualizations can be presented. The development of a system based on the proposed model can allow for easy access to recent crowdsourced data, and real-time smart city indicators such as air pollution
Detection of Broken Rotor Bars in a Cage Induction Machine Using DC Injection Braking
No full textIn this paper, an effective procedure for broken rotor bar (BRB) fault detection in a three-phase squirrel-cage induction machine (SCIM) is proposed. This approach relies on a motor current signature analysis (MCSA) by observing the specific fault-related current component generated by applying the DC injection braking method. Unlike the traditional MCSA, which is commonly focused on the detection of BRB sidebands around the fundamental current component, the proposed methodology introduces a new BRB feature in the current spectrum which makes it much easier for identification. The distinctive time-frequency evolution pattern of this feature provides the reliable identification of BRBs, even under no-load operating conditions, thus overcoming the major drawback of traditional MCSA-based methods. Fault severity classification is easily performed through the magnitude inspection of the BRB fault-related current component. In addition, the proposed approach does not require high-complexity signal processing algorithms to achieve reliable results. The proposed concept is presented theoretically, assisted by a magnetically coupled multiple circuit model of the SCIM, both with healthy and faulty rotor bars. Finally, the experimental tests validate the proposed methodology and demonstrate its effectiveness and usefulness
A decision making framework for comparing sales and operational performance of firms in emerging market
No full textSales and operations planning translates the requirements of the customers at the market place (related to new and/or existing products and services) into actionable tactical plans to drive the activities of the value chain of the organization. The present work aims to provide a multi-period and multi-perspective evaluation framework to compare the sales and operational performance (SOP) of firms in an emerging market. SOP is one of the frontline KPIs that describes the efficiency and effectiveness of the sales and operations planning. There is a scantiness in the extant literature about well-defined indicators to measure SOP. The current work fills the gap in the literature by developing a hybrid multi-criteria decision making (MCDM) framework utilizing the Logarithmic Percentage Change-driven Objective Weighting (LOPCOW) and Evaluation based on Distance from Average Solution (EDAS) models for a novel application in assessing SOP. From the data analysis, it is also evident that there is a variations in the year wise ranking of the companies. However, all individual year wise rankings maintain statistically significant correlations with the aggregated ranking For aggregation purpose, Borda Count Method is used. The companies like ITC Limited, Hindustan Unilever Ltd., Avanti Feeds Ltd., Britannia Industries Ltd., and Symphony Ltd. hold the top five positions on aggregate. The comparison with other MCDM models is made and sensitivity analysis is carried out. The present work is a first of its kind that would encourage the analysts and the policy makers to evaluate the sales and operational performance using a scientific way
Extraordinary circumstances: Covid-19-Italian Serie A scenario
No full textUnpredictable and uncontrollable situations have happened throughout history. Inevitably, such situations have an impact on various spheres of life. The coronavirus disease 2019 has affected many of them, including sports. The ban on social gatherings has caused the cancellation of many sports competitions. This paper proposes a methodology based on hierarchical cluster analysis (HCA) that can be applied when a need occurs to end an interrupted tournament and the conditions for playing the remaining matches are far from ideal. The proposed methodology is based on how to conclude the season for Serie A, a top-division football league in Italy. The analysis showed that it is reasonable to play 14 instead of the 124 remaining matches of the 2019-2020 season to conclude the championship. The proposed methodology was tested on the past 10 seasons of the Serie A, and its effectiveness was confirmed. This novel approach can be used in any other sport where round-robin tournaments exist
N-Cubic q-Rung Orthopair Fuzzy Sets: Analysis of the Use of Mobile App in the Education Sector
No full textThis study analyzes the description to examine the results of a new study and create the technique and also demonstrate the effectiveness of this technique. In this ever-changing world, students are increasingly encouraged to use mobile phones primarily to learn for educational purposes. The learning process is continuous and the goal has now been achieved. It has been replaced by online learning. Due to mobile phones as well as the many feature-oriented applications, students can study at their own place and use the application to spend their time understanding, because everything is accessible with a single click. To carry on the study we applied mobile applications for online education system. Now, because the traditional method is taken into consideration, it is normal to carry a bag full of books and copies and immerse yourself in the tradition of learning to write. However, it has been found that not all students learn when he takes notes. Therefore, we must make sure that the student focuses only on one thing at a time. To continue the research, we apply the N-cubic structure to q-rung orthopair fuzzy sets in multi-attribute group decision-making problems. This structure solves the problems of multi-attribute group decision-making techniques more generally
Fermatean Neutrosophic Topological Spaces and an Application of Neutrosophic Kano Method
No full textThe main objective of this paper is to redefine the concept of Fermatean neutrosophic sets as well as to introduce topological structure on Fermatean neutrosophic sets. The idea of Fermatean neutrosophic sets is the hybrid model of Fermatean fuzzy sets and neutrosophic sets to utilize key features of these structures. Topological data analysis for indeterminate and uncertain information is a rapidly developing field. Motivated by this recent trend, the idea of Fermatean neutrosophic topology is proposed, which is an extension of neutrosophic topology and Fermatean fuzzy topology. Some fundamental properties of Fermatean neutrosophic topology are explored and related results are investigated. Certain properties provided in the classical topological space that may not be valid in this space is one of the factors that makes the study important. Moreover, an application is made for the problem of seeking reasonable solutions to customer expectations by using the neutrosophic Kano method, which is an interesting illustration of neutrosophic decision making
Multi-paradigm modeling for cyber-physical systems: A systematic mapping review
No full textCyber-Physical Systems (CPS) are heterogeneous and require cross-domain expertise to model. The complexity of these systems leads to questions about prevalent modeling approaches, their ability to integrate heterogeneous models, and their relevance to the application domains and stakeholders. The methodology for Multi-Paradigm Modeling (MPM) of CPS is not yet fully established and standardized, and researchers apply existing methods for modeling of complex systems and introducing their own. No systematic review has been previously performed to create an overview of the field on the methods used for MPM of CPS. In this paper, we present a systematic mapping study that determines the models, formalisms, and development processes used over the last decade. Additionally, to determine the knowledge necessary for developing CPS, our review studied the background of actors involved in modeling and authors of surveyed studies. The results of the survey show a tendency to reuse multiple existing formalisms and their associated paradigms, in addition to a tendency towards applying transformations between models. These findings suggest that MPM is becoming a essential approach to model CPS, and highlight the importance of future integration of models, standardization of development process and education
Autonomous Bus Operation Alternatives in Urban Areas Using Fuzzy Dombi-Bonferroni Operator Based Decision Making Model
No full textAdvances in V2V, V2I, and autonomous vehicle technologies have made autonomous buses possible in cities. Soon, autonomous bus operations will be common in urban areas, which will improve sustainability, safety, and the city's technology. These buses have different operation types. Each operation has advantages and disadvantages. Therefore, the goal of this study is to serve as a guide for decision-makers during the transition to autonomous buses. Four alternatives are evaluated based on eleven criteria organized under four main aspects, namely autonomous buses for special uses, autonomous buses for last-mile uses, autonomous cars in mixed traffic, and autonomous buses in closed systems. We propose an Ordinal Priority Approach (OPA) method for determining the criteria weights and application of fuzzy Dombi Bonferroni (DOBI) methodology for the evaluation of alternatives. When compared to the other three alternatives in this study, the results show that deploying autonomous buses in mixed traffic is the most advantageous option
Measurement properties of New Mobility Score to evaluate functional recovery in the elderly following total hip arthroplasty
No full textUvod/Cilj Cilj ove studije je da se identifikuje i ispita upotreba Novog upitnika skorovanja mobilnosti (NUS) u proceni funkcionalnog oporavka tri meseca nakon totalne artroplastike kuka. Metode U istraživanje je uključeno ukupno 70 pacijenata, starijih od 60 godina, koji su bili podvrgnuti totalnoj artroplastici kuka. Ispitivana grupa je podvrgnuta sveobuhvatnom programu rehabilitacije, a kontrolna grupa standardnom. Primarni ishod funkcionalnog oporavka je ocenjen Harisovim upitnikom za kuk (HUK) i NUS, a sekundarni Opštim upitnikom o zdravlju (SF-36). Upitnici su popunjavani preoperativno i tri meseca postoperativno. Rezultati Ispitivana grupa je u odnosu na kontrolnu pokazala značajnije poboljšanje tri meseca posle artroplastike kuka. Korelacija u obe grupe između HUK i NUS je bila vrlo jaka (r > 0,700). U ispitivanoj grupi je tri meseca postoperativno pokazana jaka povezanost između ukupnog fizičkog oporavka (UFO) SF-36, HUK i NUS (r > 0,700), umerena do jaka između kategorija bola, HUK (r = 0,380; r = 0,583) i NUS (r = 0,424). U kontrolnoj grupi je pokazana jaka korelacija između UFO SF-36, HUK (r = 0,704) i NUS (r = 0,568) i umerena između kategorija bola i HUK (r = 0,546; r = 0,466). Područje ispod krive (AUC) pokazalo je validnost svih korišćenih mernih instrumenata: AUCNUS = 0,724, r = 0,001, AUCHUK = 0,788, p = 0,000 i AUCUFO = 0,747, r = 0,001. Zaključak NUS može uspešno da se koristi u rutinskoj kliničkoj proceni funkcionalnog oporavka starijih pacijenata posle totalne artroplastike kuka. Istraživanje je registrovano u registru ISRCTN (https://doi. org/10.1186/ISRCTN73197506).Introduction/Objective The aim of this study is to identify and evaluate the use of New Mobility Score (NMS) in estimating functional recovery three months after total hip arthroplasty (THA). Methods In total, 70 patients, aged > 60 years, underwent THA. Treatment group was subjected to the comprehensive rehabilitation program and control group to the standard one. Primary outcome was assessed with Harris Hip Score (HHS) and NMS, and secondary one by Medical Outcomes Health Survey (Short-Form Health Survey - SF-36). Questionnaires were collected before and three months after hip surgery. Results Treatment group showed significant improvement three months postoperatively. The correlation in both groups between HHS and NMS was very strong (r > 0.700). Treatment group following surgery showed strong correlation between Recovery through Personal Care Services (PCS) and HHS and NMS (r > 0.700), moderate to strong between pain categories and HHS (r = 0.380; r = 0.583) and NMS (r = 0.424). Control group showed strong correlation between PCS and HHS (r = 0.704), and NMS (r = 0.568) and moderate to pain categories and HHS (r = 0.546; r = 0.466). The area under the curve (AUC) described the inherent validity of all measurement used AUCNMS = 0.724, p = 0.001, AUCHHS = 0.788, p = 0.000 and AUCPCS = 0.747, p = 0.001. Conclusion The NMS could be successfully used in routine clinical assessment of elderly patients following THA. The trial is registered in ISRCTN Register with https://doi.org/10.1186/ISRCTN73197506
A hybrid XSS attack (HYXSSA) based on fusion approach: Challenges, threats and implications in cybersecurity
No full textCross-site scripting (XSS) attacks have been extensively studied in the literature, although mitigating such attacks remain a challenge for cyber defenders. In this paper, we survey the existing literature on XSS attacks, focusing on the range of attacks and potential mitigation strategies. Specifically, we review the various XSS attacks from the lens of an attacker. We use a workflow diagram to define the topological relationship among XSS attacks, and to highlight key system weaknesses (e.g., chokepoints). We also present a Hybrid XSS attack (HYXSSA), designed to facilitate the identification of existing and future potential attack vectors in different modalities presented as frameworks (fi). For quantification and visualization of these frameworks, the software application as a rotate view tool is developed. Moreover, we demonstrate how these derived frameworks can be implemented, and provide a guideline to defend against XSS attacks. The implementation results for the given two attack vector shows the feasibility of mapping of attack vectors to actual mathematical vectors. Finally, we present potential challenges and opportunities associated with XSS attacks