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2215 research outputs found
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The Sources of Meaning in Life Among Educators of Socially Vulnerable Adults
No full textLife work considered as a critical source of meaning in life. This can be particularly true for the educators who choose to work with and teach adults who belong to socially vulnerable groups. To this context, the aim of our study was to investigate the sources of meaning in life of educators of socially vulnerable groups, and the possible relation between the sources they derive meaning from and their decision to work with this specific kind of students. A total of 12 educators were interviewed providing information regarding their experience in working with socially vulnerable groups, their motives considering their professional choice, the way they perceive themselves as teachers of vulnerable adults and the sources of meaning in their lives. Thematic Analysis was used to analyze the data. It was found that the primary sources of meaning in life of the participants are (a) interpersonal and social relations, and (b) personal relationships; moreover, there is a close relation between the participants' sources of meaning in life and their perception about vulnerability.3311411
Efficient Privacy Preserving Record Linkage at Scale using Apache Spark
No full textSoundex has been used for over a century for approximately matching records based on their phonetic footprint. In this paper, we examine a series of techniques a practitioner might employ in order to increase the algorithm's matching capabilities, when utilizing Soundex for privacy preserving record linkage and a protocol based on Apache Spark, suitable for big data processing. We provide a detailed empirical assessment measuring matching quality and time performance of the proposed alternatives, showing that we achieve both precision and recall over 95% for large datasets in a few seconds and without utilizing any privacy-preserving blocking technique.4024072022 IEEE International Conference on Big Data (Big Data
A Model of Economic Growth and Long Cycles
No full textThe purpose of this article is to derive an endogenous growth and cycles model that integrates the general law of capital accumulation, the reserve army of labor, technological change, devaluation of capital, and the law of the tendential fall in the rate of profit. The phase space of this model is analyzed by estimating its equilibrium solutions and exploring its economically meaningful stability properties. The so-derived endogenous growth-and-cycles model is then simulated with realistic parameter values. The solutions of our model display periodicity, which may be treated as long cycles like attractors conditioned by the long-run movement of profitability. The salient feature of our model is the growth of the rate of surplus value, which becomes theregulating variable of our system for it explains the deviations from equilibrium and at the same time provides a realistic solution to Harrodian instability.55335138
A note on the zero-sum gains data envelopment analysis model
No full textIn the case of the proportional output reduction strategy with a single output, the Variable-Returns-to-Scale (VRS) Zero-Sum Gains Data Envelopment Analysis (ZSG-DEA) efficiency scores can be obtained from the VRS conventional DEA efficiency scores by means of the Target’s Assessment Theorem (TAT). Using TAT as a departure point, two relations for computing the ZSG-DEA efficiency scores appear in the literature. Our objective in this note is to compare, contrast and challenge them on both theoretical and empirical grounds. For the latter, three different data sets are used.2231737175
A Secure Network Model Against Bot Attacks in Edge-Enabled Industrial Internet of Things
No full textThe new Industry 4.0 standard has offered many advantages to the industries improving their production rate since it evaluates novel cutting-edge technologies like artificial intelligence, machine learning, cyber-physical systems, and Internet of Things (IoTs) to automate manufacturing processes so as to minimize time and economical costs while improving the quality of products. However, this rapid industrial transition carries risks in terms of security and privacy issues that arise. In this article, we propose a novel secure network model to enhance network security and employees’ privacy in the edge-enabled industrial IoTs. Experimental results demonstrate encouraging performance rates in terms of accuracy, precision, recall, fall-out, F-measure, and Matthews correlation coefficient against known and unknown bot attacks.18117998800
Big Data Applications in Food Supply Chain Management: A Conceptual Framework
No full textThe paper provides a systematic review and analysis of the current literature on big data (BD) applications in the context of food supply chain management (FSCM) in order to categorize the state-of-the-art research trends exploring the adoption and implementation of big data analytics (BDA) across different segments of food supply chain (FSC). The use of BDA brings the digital transformation of FSCs closer providing sustainable implications and added value to their operation. Harnessing BD’s potential is becoming more and more relevant in addressing the constantly evolving complexities in food systems. However, the field of BD applications in the FSCM domain is severely fragmented and relatively "primitive". The present research is one of the earliest attempts to recognize and present a comprehensive analysis for the BD applications across different segments of FSC proposing a conceptual framework that illustrates the role of BD in a data-driven FSCM environment. For the purposes of our research, we adopted the systematic literature review (SLR) method aiming at the identification of the dominant categories and themes within the research area. Based on the SLR findings, we propose a conceptual framework that captures the interconnection between FSC performance and BD applications by using the input-process-output (IPO) model within a data-driven FSCM context. The main research contribution lies on the thematic classification of relevant research, the conceptualization of this fragmented field, the development of a conceptual framework, and the presentation of a future research agenda pertaining to BD applications in a data-driven FSCM context.147403
Convergence in retail gasoline prices: insights from Canadian cities
No full textThis paper investigates the extent of convergence club formation in retail gasoline prices. Our study provides new insights through the use of a large disaggregated panel database for Canada that comprises three types of gasoline grades, namely regular, medium and premium, for a sample of 44 cities over a period of almost two decades. The paper analyses gasoline price data that are inclusive or exclusive of taxes. The findings suggest that the retail gasoline markets are not integrated in terms of requiring multiple numbers of convergence clubs to explain relative price movements across cities. In addition to this, wholesale gasoline prices across cities are probably less integrated than retail prices. Key drivers of retail price divergence across cities include distances between cities and the need to be explicit on distinguishing fuel quality. These findings are robust to the inclusion or exclusion of taxes in retail gasoline prices.68120722
Diffusion of Innovations in Middle Eastern versus Western Markets: A Mathematical Computation Cellular Automata Simulation Model
No full textSimulation modelling has gained ground over the years since it can provide various scenarios applied to any scientific area. In this study, a stochastic cellular automata model is proposed, in which agents fall into three distinct categories (adopters, non-adopters and denials). Based on Hofstede’s cultural dimension individualism, we characterize three major international markets, as perfectly clustered (collective) to perfectly random (individualistic). We investigate innovation diffusion speed, in each network topology. At each time step, the decision of non-adopters to purchase innovative products, is affected by their immediate neighborhood (von Neumman). The speed of diffusion is evaluated using time at which sales reach 50% of market. Effects of simulation parameters on speed of diffusion, are assessed using a log-normal accelerated failure time model. Results demonstrate that diffusion of innovative products accelerates when innovators of a virtual economic system are placed according to a random network and when amount of innovators and imitators in the economic system increases. Slower innovative products’ diffusion process is a result of a large amount of denials and of how imitators are placed in the in the virtual economic system. Diffusion in small-world virtual economic systems lead to small time inflexion points very close to those of a random networked market.221597161
Digital competencies for online teachers
No full textThe COVID-19 crisis forced most educational institutes worldwide to deliver teaching via the internet. However, neither teachers nor students were prepared for such an abrupt disruption. Specifically, many teachers lacked the appropriate digital competencies to effectively teach online. So, what are the necessary digital competencies that teachers should have in order to effectively teach online via the internet? This study proposes a framework of such digital competencies for online teaching that outlines the essential digital competencies needed for online teachers to effectively implement the Online Teaching Preparation, Deliver, Evaluation, and Revision (Online Teaching PDER) framework. Based on this framework, online teachers can self-reflect on their digital competencies in a systematic way and then take appropriate training to enhance their skills. Also, educational institutes can be informed by this framework to prepare the appropriate syllabus and educational material for educating future teachers as well as training in-service teachers.19
Economic complexity of cities and its role for resilience
No full textThe aim of the paper is to propose the construction of an index that captures the economic complexity of cities over the globe, as well as to explore whether it is a good predictor for a range of city-level economic outcomes. This index aspires to mitigate data scarcity for cities and to provide policy makers with the tools for monitoring the evolving role of cities in the global economy. Analytically, we implement the economic complexity methodology on data for the ownership, location and economic activities of the world’s 3,000 largest firms and their subsidiaries to propose a new indicator that quantifies the network of the largest cities worldwide and the economic activities of their globalized firms. We first show that complex cities are the highly diversified cities that host non-ubiquitous economic activities of firms with global presence. Then, in a sample of EU cities, we show that complex cities tend to be more prosperous, have higher population, and are associated with more jobs, human capital, innovation, technology and transport infrastructure. Last, using OLS methodology and accounting for several other confounders, we show that a higher ECI, at the city level, enhances the resilience of cities to negative economic shocks, i.e., their ability to bounce back after a shock. Specifically, we find that the expected increase of the ratio of employment in 2012 over 2006 is 0.01 (mean: 0.992; standard deviation: 0.081) when the ECI increases by 1 unit (mean: 0.371; standard deviation: 1.094), i.e., a satisfactory pace of recovery, in terms of employment. The ability to diversify in the presence of a shock, the reallocation of factors of production to other sectors and the ability to extract rents associated with those diversified activities, uncovers the mechanics of the ECI index.178e026979