Browsing by Type "Article"

The paper has as subject the modeling and forecasting of air quality impact on mortality rates, and present a case study, making use of time series analysis approach. After a general view on the time series models, regression and intervention models, to be used in modeling and forecasting of mortality, function of air quality, some methodological aspects of time series modeling and forecasting, based on Box-Jenkins methodology, are discussed with the emphasis on practical aspects. Finally, a case study using a multiplicative transfer function model with three exogenous variable representing ozone, daily average computed for the region, particulate matter 10 micrometers or less in diameter, daily average, and temperature mean, daily average, considered as risk factors, with the effect on mortality rate, as endogenous variable, is presented.

The demand for ensuring and strengthening safety and security measures is constantly growing, requiring personalized monitoring of children throughout the school program. The education system should place greater emphasis on the presence and monitoring of students during the school year. A strong tracking system and managing and tracking student attendance can help improve safety and security in schools. Based on the analysis of the literature in the field, the author briefly presented notions related to RFID (RadioFrequency Identification), the benefits of this technology, and a conceptual model of an RFID presence monitoring system developed on an IoT platform. It is expected that the results obtained by using this system will be able to support the processing of school data, to automatically generate accurate statistical data and to be able to reduce data manipulation. The application will allow the permanent visualization of students’ presence by parents and teachers and their warning if the presence of students reaches a critical value, which is an element of novelty.

The aim of this paper is to develop a group decision approach for the supplier selection problem. Suppose that a manager wants to purchase a set of devices based on the offer of a few suppliers such that several constraints are met. The proposed decision support approach combines a group decision method that calculates the performance devices and the selection risk associated with it, as well as a Multi-Objective model for the supplier selection. Every single device is evaluated by a group of evaluators across a certain set of criteria. The divergent opinions of the evaluators generate the selection risk related to the respective portfolio of devices. A new Multi-Objective model for the supplier selection problem is formulated. It has two objective functions: risk minimization and performance maximization. Starting from the aforementioned model a minimum risk model with budget and performance constraints has been formulated. A case study connected with the purchase of certain medical devices has been conducted and the related numerical results have been analysed. Our approach can help managers in the purchasing management. Based on it a software module can be realized and embedded in a decision support system.

Modeling and simulation are some of the most advanced and powerful tools for analyzing operational performance in companies to support continuous adaptation to market needs. There is a wide range of simulation software packages available on the market. They offer a large variety of applications, have different prices and features and use different modeling approaches and strategies. This article develops a approach based on a multi-criteria method that helps companies select the right simulation software, that will improve the company's productivity. Because the problem of selecting a software product is a multicriteria decision problem with contradictory objectives, we shall use the extension theory and the MatterElement (ME) method for solving it. The ME method for several alternatives and a single level of the criteria is presented in steps. The multi-criteria approach is applied for a case study connected with selection of simulation software. Three alternatives are evaluated according to 17 criteria that are of interest to the manager. The approach offers a structured way for describing the problem that takes into account the criteria related to the features of the simulation software. The weights associated with the criteria are chosen in such a way as to ensure a correct evaluation of the alternatives in order to achieve a set of objectives.

A way of highlighting and promoting the most important and significant components of the national heritage is to harness them through Internet-based technologies. This paper presents the proposed digital solution for the promotion and preservation of collections of information from the Romanian literary patrimony using intelligent digital solutions for the extraction and systematization of knowledge. This digital solution, a platform, will offer advanced, intelligent semantic search and analysis services and prediction forms concerning Romanian literature. This paper presents several important platforms, systems and projects that are linked to the Literary Heritage. Then, a comparative analysis of the functionality, limitations and opportunities of the most relevant online platforms is presented, followed by the description of the main features of INTELLIT platform.

In this paper, we propose a new method for solving linear algebraic systems based on the KSOR method. The new approach introduces a new coefficient in the assumed updated section from the KSOR method. It obtains the same solution as KSOR for a given linear algebraic system, but in order to get this, we have to modify the diagonal of the coefficient matrix of the initial system. The new method reaches the solution in fewer steps than KSOR on certain examples, but we have an additional step for the modification mentioned above with O(m) complexity, while a normal step of iteration has O(m2) complexity, so overall our method has better performances than KSOR method. Furthermore, on certain examples, the spectral radius of the iteration matrix of the new method is strictly less than the one of KSOR and MKSOR methods.

Under the complex conditions of the current operational environment, the public institutions face actional difficulties caused by information intensification, accelerating work processes, limiting resources and reducing response times. A solution for gaining and maintaining a competitive advantage can be to streamline the activities of these institutions by implementing an information integrated system for management of activities which offers quality, safe and interoperable facilities and services, using current IT developments. In the same context, ensuring system security is one of the main objectives for digitizing the services and products offered.

Physical therapy helps patients during their rehabilitation programme after orthopaedic post-operative interventions or in case of musculoskeletal injuries. For a full recovery and a minimisation of the risk of complications, the prescribed in-clinical therapy sessions must be supplemented by independent home training. The purpose of this paper is to present the emerging technologies used for monitoring ortophedic movements and to introduce an innovative telerehabilitation-as-aservice solution, called re.flex, which consists of two IMU (Inertial Measurement Unit) motion tracking sensors and a mobile application The therapist makes use of standardised digitised physical exercises that are carefully chosen so as to create, by selection, a custom designed training program that will meet the needs of each patient. The feedback provided by the sensors enables the therapist to a) monitor the patients’ compliance with the training program in a transparent manner, b) keep track of the documentation related to the recovery progress through data-collection during in-clinical and in-home exercise-based rehabilitation c) customize the training program. The real-time 3D smartphone animations and the direct visual, audio and haptic feedback from the sensors assist patients in performing the rehabilitation exercises assigned to them. The abovementioned application allows the patients to visualise their injured limb on their smartphone or tablet in an innovative 3D – 360° manner, thereby reducing their fear of making mistakes during the recovery process and offering them constant security. The study evaluates the effects of this kind of approach for a group of 30 participants and the results recorded are in favour of the patients recovering with re.flex.

The invasion of the daily world by the digital has led to the need for scientific understanding of the functioning of this space. In this paper I will analyse from a sociological point of view the social order of digital space, cyber crime and cyber security having as a premise the fact that digital space facilitates the deviance because its intrinsic characteristics but also because it is still an anomic environment. For this purpose, I analysed comparatively a series of pairs: norms and social order - digital social order, social deviance - cybercrime, social control - cybersecurity. From the analysis made it follows that the theories formulated by sociology to explain the classical social reality are also applicable to the understanding of the digital space. The general rules of behavior, the trends and biasis of people can be found in the cybernetic environment.

We present new algorithmic results for the class of Helly graphs, i.e., for the discrete analogues of hyperconvex metric spaces. Specifically, an undirected unweighted graph is Helly if every family of pairwise intersecting balls has a nonempty common intersection. It is known that every graph isometrically embeds into a Helly graph, that makes of the latter an important class of graphs in Metric Graph Theory. We study diameter and radius computations within the Helly graphs, and related graph classes. This is in part motivated by a conjecture on the finegrained complexity of these two distance problems within the graph classes of bounded fractional Helly number — that contain as particular cases the proper minor-closed graph classes and thebounded clique-width graphs. Note that under plausible complexity assumptions, neither thediameter nor the radius can be computed in truly subquadratic time on general graphs.

This paper addresses the problem of proactive planning and optimizing the operation of a Systems of Systems (SoS) over a time horizon while considering the characteristics of each constituent system and complex interactions among them. We define a mathematical formalism for modeling complex systems composed of a mesh of sub-systems with linear and non-linear behaviors and abstractions like discrete time, atomic systems and interconnection of atomic system. The proposed modeling approach is simple enough to allow fast computations and simulations, and at the same time complex enough to capture the essential features of the real system thus allowing the mapping of proactive optimization problems to Mixed-Integer Optimal Control Problems. The proactive planning uses hierarchical optimization processes that compute predictions and optimization plans at various time granularities, each finer layer plan adjusting and refining the ones with higher granularity. To show case our approach we model a Data Center which is a well-known case of a large scale complex system aiming to plan and optimize its operation to use as much as possible the locally produced renewable energy and optimize its integration in smart grid advanced context. Simulation based results show a reduction of 5% of the carbon footprint and at the same time an increase in profit of more than 14% due to flexible energy shifting.

Time Series Database (TSDB), is a particular type of data repository. TSDBs are capable of diverse functionalities regarding operations on time series data and are developed using different technologies. A large number of TSDB solutions, available both as open source and commercial software, has emerged in the last years. Selecting the proper TSDB is a challenging endeavour for a potential enterprise client. In this paper, a set of open-source TSDBs which includes InfluxDB, Graphite, RRDTool, Prometheus, OpenTSDB and TimescaleDB - has been selected for analysis, evaluation and ranking. A comparison of TSDBs implies the establishment of a set of attributes. A set of quantitative and qualitative attributes which have different scales and units of measure has been selected. The problem of selecting or ranking TSDBs evaluated in this paper with a set of attributes is a Multi-Attribute Decision Making problem (MADM). For solving the TSDBs evaluation, analysis and selection a multi-attribute TSDBs maturity model has been proposed. The model for the selected TSDBs set and for the 18 attributes, 10 quantitative and 8 qualitative, has been validated. The model for all the attributes, both quantitative and qualitative, has been solved and, finally, a comparison between the obtained rankings has been made. The comparison of the ranks obtained shows that the leading TSDB is InfluxDB.

This year the evolution of the strategy and plans implementation in order to combat climate change through energy efficiency measures has been confronted with a new challenge, namely the impact of the COVID-19 pandemic in all areas of life. At a time when the expansion of IoT use through platforms to monitor, scale and optimise processes specific to urban agglomerations and industrial centres, the digitisation of the energy sector has acquired a new dimension and a central place in the sphere of priorities for the coagulation of the financial efforts. The article presents the status of the implementation of this objective prior to the pandemic period, the new conditions and priorities imposed on the basis of changes in electricity consumption and the opportunities for the development of IoT-based systems for the energy sector. At present, some of the major challenges to be addressed to smart technologies are: accelerating the pace of deployment, achieving the mix of energy from traditional and renewable sources, securing energy systems and networks in order to resist in the situation of potential variable energy flows or cyber attacks.

Critical infrastructure is foundational for the prosperity and quality of life in any society. By definition, its destruction or disruption would cause severe damage and possibly loss of life. Within this understanding, space systems are a new category of critical infrastructure, emerging as an enabler of new applications which are critical within the wider system-of-systems. This paper presents the results of a modeling exercise validating the proof of concept regarding the idea of the global, air-transport-critical infrastructure’s dependence on space systems. By using an open-source application, the authors constructed a complex system made up of 18 airports for which six scenarios were modeled that represent either the exposure to specific space phenomena or the effects of a partial or total critical space infrastructure disruption. Despite the limitations and assumptions made in the building of this model, its results suggest that a significant impact would result from disruptive events, with the potential for cascading disruptions within the system, beyond the system under analysis, and into the wider system-of-systems. Tools such as this model are useful to policy- and decision-makers, not only to protect existing, critical infrastructures, but also to adequately source future risks, vulnerabilities, and threats, and design and build new infrastructures.

The rise of Web-based publishing and the increase of electronic usage has triggered profound changes in academic publishing and has determined national governments to take some forms of action designed to actively promote and support the publication of high-quality scientific literature produced in their own country. Considering the spread of ICT technologies nowadays, an online platform was developed in order to encourage participation in the grant competition for Romanian scholarly publications and establish a digital connection between the main actors involved in the process. In this context, the article presents the system architecture, development and outcomes. Building such a platform has required gathering and studying accurate information for data aggregation and user experience, having in mind a scalable design for requirements update or further developments. The system revolves around digitally connecting three major actors – publisher, evaluator, competition organizer. For ensuring the platform’s reliability and preventing failures, user-centric tests were developed and set to run automatically at specific triggers, such as code submission. The platform contributes to the transparency of the entire grant management process, substantial reduction of the time for submission, and streamlining of the evaluation procedures. The web platform has been effectively developed, implemented and regularly used by both publishers and reviewers in the latest Romanian grant competitions.

Globally, the population is ageing and the number of older people is increasing dramatically. These are challenges for healthcare systems because an increased need for medical assistance is related to ageing. The availability of health-related data and information is a main issue for assessing the health status of seniors, having an important impact on their quality of life. Due to Internet of Things (IoT), cloud computing, smart environment, and virtual machines, the traditional healthcare approaches are replaced by up-to-date (remote) health monitoring systems in smart environments. The paper presents the opportunities provided by such solutions for an appropriate management of older people health related information. RO-SmartAgeing, a remote health monitoring system based on IoT, is presented as a case study with the intention of revealing the rise of the efficiency and the decease of the response time in seniors remote monitoring systems.

Software testing is one of the most, if not the most critical phase of the Software Development Life Cycle and this is because it is the phase in which are measured the quality assurance criteria and the Key Performance Indicators already set for releasing software in the production environment. The paper presents an analysis of the most comprehensive seven tools used for automated testing with the purpose to offer an objective approach for choosing an automated testing tool. In the paper, one can find, in a structured manner, a short description of the tools under investigation with advantages and disadvantages followed by a synthetic comparison between them based on eight criteria.

The evolution of the digital economy and society is reflected in an overall increase in the economic efficiency and improvement in all areas. It is essential that the progress of the digital society is constantly monitored for a vision of the implementation of the strategies pursued. This article presents an analysis of the digital society from the perspective of the priorities established by the National Strategy for the Digital Agenda 2020 following the stage of digitalization of the Romanian economy in relation to European trends. The paper presents the evolution of the Digital Economy and Society Index (DESI) indicators and of the National Strategy on Digital Agenda for Romania (SNADR) indicators between 2016 and 2019, highlighting the situation in Romania, providing a theoretical basis for strategic guidelines, as well as a comparation between DESI and SNADR indicators.

This paper proposes the DANP (DEMATEL-based Analytic Network Process) method so that the factors that affect the quality of IoT (Internet of Things)-based smart wearable devices can be adequately assessed. The proposed method helps to identify and visualize the importance of certain factors (dimensions and criteria), the causal relationship among the factors, the mutual influence upon each other, and their influential weights. A numerical example was presented to illustrate the feasibility and effectiveness of the proposed method. The results of this study demonstrated that the quality dimensions can be divided into a causal group (the technical and ergonomic dimensions) and an effect group (the functional and symbolic dimensions). The functional dimension proved to be the most important factor and the most important core problem to be solved. The most influential driving factor was the ergonomic dimension. The results of this study provide insights into critical design criteria to better meet the users’ needs and can be used by manufacturers to develop strategies for improving the quality of IoT-based smart wearable devices, in a priority order.