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Accessibility to urban facilities and public services is nowadays one of the key factors that impacts the quality of urban live. That being said, accessibility is a complex concept, which although in common use, has a range of meanings, and measuring it raises numerous methodological problems. For instance, accessibility is closely related to the concept of distance, but as a society evolves, other factors such as travel time, economic cost, different transport options, interest or attraction of the destination co...

Digital ecosystems represent a new technology capable of interconnecting heterogeneous, cross-domain platforms, able to drive innovation in different industries, enabling us to connect and operate with a wide range of actors, customers, partners, companies. Digital ecosystems can be considered as socio-technical clusters of adaptive applications with different levels of context awareness, adaptability and autonomicity. The adaptive properties of an organism are closely related to the self-organizing property and t...

Approximation of multi-extremum functions problems arise in a wide range of fields including deterministic and stochastic technics, multi-parameter optimization. The main focus of this thesis is to consider the different principle of approximation problem. Experimental definition of external impacts on complex technogenic systems is related to technical difficulties. This area of research arises from the fact that many problems of multi-extremum optimization are known to be computationally difficult (NP-hard). We ...

Petri nets is the well-known mathematical tool for the modeling and verification of parallel systems of all kind. Multiprocess Petri multinets with time stamps (MPTSM) are the newly introduced class of low-level Petri nets, whose definition and the properties are the main topic of this article; they generalize the properties of P/T Petri multiprocess multinets in the area of design, modeling and verification of generally parallel programming systems with the discrete time. The MPTSM with the support of the ASYNC-C...

Process and plant design need to be continuously improved, the use of new safety concepts to a full extent being one of the key parameters leading to their sustainable improvement. Accidents occurred over time in industrial facilities where explosive gas or vapor atmospheres may be present have put the explosion risks high on the agenda of regulators, operators, accident investigators or researchers in the field. Accidental flammable gas leaks in mixture with air may generate explosive atmospheres which once ignit...

This article presents an approach for managing and comparing data, concerning some main food products in Bulgaria. The source for the search of these product categories (bakery products, milk and milk products, fish and fish products and etc.) is the created relational database. The extracted data for the selected category have been grouped, compared and processed. The obtained results enable the user to present relevant conclusions for the examined time interval. This approach is applied to the data on bread and ...

The transition to advanced digital, intelligent production technologies, the creation of systems for processing big amounts of data, machine learning and artificial intelligence is caused, among other things, by the need to move to a new level of digital energetics, which ensures the interrelationship between the generation, distribution and consumption of energy resources and their effective management. The efficiency of the use of energy resources is one of the urgent problems in the energy sector. One of the pr...

In this research we investigate the significance of the CGAL library which is a source of algorithms related to computational geometry. We briefly describe the exact computation paradigm that provides obtaining reliable geometrical results. We present the advantages of using the CGAL library in terms of investigating certain parameters of geological planar structures. We show that several parameters that can be computed and attributed to considered planes and subsequent use of further statistical methods becomes p...

The advancement of tracking technologies such as RFID (Radio Frequency Identification) in recent years supported the study area of shopping behavior of consumers in retailing setting has globally regained increased interest. However, only few studies have attempted to analyze consumer shopping behavior using the RFID data. The purpose of this paper is to propose the framework based on behavioral and environmental variables, which can be tested using the RFID data obtained from the recent experiment in one of the s...

The sudden and intensive variations of the ionosphere could be represented through its basic property ? electron density which is the main parameter concerning radio propagation through this part of the atmosphere. It is radio sounding as one of the main measurement methods applied among numerous methods for electron density estimation suitable for different ionosphere sub-regions monitoring as a part of the remote sensing Earth observation technics. Collecting VLF/LF (3-300 kHz) radio sounding data which reflect ...

The comparative analysis of approaches to the management of surface water bodies in Ukraine, taking into account the provisions of the European Union (EU) Directive on river basin management plans in monitoring surface waters using geoinformation systems (GIS). The main deficiencies of the system of state monitoring of surface waters are identified. The introduction of GIS technologies for estimating and predicting changes in surface waters is proposed to take the necessary measures for the adoption of environment...

An algorithm for extracting information on the types and subtypes of soils for each pixel of big data sets of remote sensing on agricultural lands is proposed. For this, a mathematical apparatus for constructing a multi-temporal (empirical) soil line is used. The classical soil line (SL) is defined in the RED-NIR spectral space by two coefficients "a" and "b" [2, 6, 9]. In this form, SL does not characterize soil types and subtypes. A multi-temporal soil line (MSL) is the major axis of an ellipse that describes al...

The paper deals with the problem of evaluating the characteristics of information systems at the design stage. In the design of ERP-systems the most interest characteristic is not the average time, but the probability of timely delivery of different type messsages (for example, command, service, multimedia, files, etc.) from the sender to the recipient. In addition, the possibility of using the priority information management built on the basis of service disciplines of general form with mixed priorities must be c...

This paper describes an analysis of concrete pavement loading while taking into account deflections and deformations. Concrete pavements are generally durable and have low demands on maintenance within their whole lifecycle. The first part describes an experimental road test section with verified material characteristics of individual pavement construction layers by laboratory and non-destructive testing. Furthermore, the position of temperature sensors in road structure is described, together with loading data an...

The estimation of groundwater levels in a basin is a very important factor for planning integrated management of groundwater and surface water resources. In this study, artificial neural network models have been developed for predicting and forecasting of groundwater level. The reliability of the computational models was analyzed based on simulation results and using three statistical tests including Pearson correlation coefficient, coefficient of determination and root-mean-square error. The artificial neural net...

Accurate prediction of reference evapotranspiration (ET0) is essential in water resources planning and management of irrigation systems. The ET0was determinate using the FAO-56 Penman-Monteith equation based on the weather data collected in Serbia during the period 1980-2010. The purpose of this research is to develop and apply the Extreme Learning Machine (ELM) to estimate and calculate the ET0. The process was implemented for eight input combinations in order to find the most optimal input combination for ET0 pr...

The customer expects the quality and reliability of purchased devices. Every defect on the device causes loss of brand confidence and customer dissatisfaction. Customer satisfaction is, however, the best indicator of how likely customers will continue to buy in the future. If an organization wants to maintain a customer, it must be customer-oriented. The company has decided to improve the quality and reliability of its products. This can also help to increase the number of satisfied customers and gain competitive ...

Sources that contain data about tourism in Bulgaria are both structured and unstructured. Information from these xls and pdf files is organised in a created relational database. The database stores time series on tourism flow (trips of Bulgarian residents abroad and foreign tourists to Bulgaria), expenditure of outbound tourists, revenues from international tourism and employment in tourism. This article studies time series on trips of Bulgarian residents abroad (outbound tourists) by country of destination and by...

With the steady rise of interest in blockchain and related technologies, researchers are making efforts to solve the remaining open questions in this field. One of the open problems is to achieve and maintain some desired characteristics of a private blockchain as far as the block generation rate is concerned. This problem is routed in statistical modeling. In this work, we will apply the results of participatory computing to build private blockchains and to resolve this issue. Private blockchains are important in...

Further development of digital economy requires researching the limits of some algorithms applicability. These algorithms are based on the mechanisms obtained as a result of investigating the processes of ?alive? nature. Such algorithms were called the bio-inspired algorithms and are widely used in practice, for example, for solving the problems of multi-agent systems coordinated control. Application of coordinate descent, a type of gradient method ? extends the description of the existing shepherd dog algorithm. ...

This paper is about the reconfiguration of a simple radio frequency (RF) front-end transceiver belonging to an embedded system applied in the automotive industry, inside of the remote keyless entry (RKE) and part of the tire-pressure monitoring (TPMS) system on a car. The main concern of this article is to reduce volume and complexity as well as a lower radiation. The new product must keep the same at least the same RF performances or even higher ones in some situations. We also perform an impedance analysis for r...

From a structural optimization point of view, the design of steel lattice towers begins with choosing from various alternatives to develop the geometry of the incorporated trusses. The biggest challenge is to find optimal geometry based on experience. In contrast to some structures that are generally intuitive to construct, (e.g. common buildings structures), the same design for the tower structures is frequently built for several times. Thus, cost savings and performance improvements obtained by structural optimi...

Segmentation of badly structured images is a complex task for different models of artificial intelligence systems. The given work presents algorithmic solutions for intercellular relations measurement in peripheral blood. There has been proposed hybrid algorithm, allowing to distinguish three classes of formed elements: ?erythrocyte?, ?leukocyte? and ?not erythrocyte and not leukocyte?. The algorithm provides for two-level processing of the image. Analysis of geometric attributes of image segments and their colour...

Autostereoscopy is a method for effective visualization of three-dimensional models with the help of ordinary imaging techniques. It allows achieving the 3D object observation without the need for special goggles, displays or other equipment. The Method itself is using rapidly alternating images of given object taken from defined angles, mimicking the position of the human eyes. Such animation induces a sense of depth. Autostereoscopy can be applied to a static image or even dynamic video materials. Firstly, we ha...

The work considers information and computing technologies supporting regional deci-sions making and based on geoinformation web-systems and mapping web-services. The use of such systems for the information support of regional management is now becoming common. Long-term strategic forecasting and planning of territories development, solu-tion of various institutional and sectoral problems today are often based on the use of integrated information and computing environment, complex information systems of re-gional m...

The low ionospheric monitoring by very low and low frequency (VLF/LF) radio waves generates big databases containing information on high temporal resolution relevant to specific spatial areas. These data allow us to detect and model perturbations induced by different events. In this paper we present analyses of data relevant to periods around natural disasters. Our attention is focused on the tropical depressions which have been detected before the hurricane appearances in the Atlantic Ocean and the earthquake occ...

The last decade has witnessed an exponential increasing in the number and the size of data centers. This expansion was driven by the increasing demand for digital products and services from the various sectors of the economy. Data center operators are faced with an increasing pressure for managing their facilities more efficiently and cost effectively such that they achieve 100 percent uptime. This is a difficult task to overcome, taking into account that energy consumption is the fastest growing component of data...

Managing knowledge is the most important part of every enhanced process. Well-adjusted knowledge management leads to effective way of sharing knowledge, its comprehension, visualization and managing other processes connected to it. New trend in the field of Civil Engineering and Building Design is BIM ? Building Information Modeling. Management of Building Information Modeling is very current topic linked with the creation of building modeling and knowledge sharing processes used by the Architecture, Engineering a...

The issues of teaching C++ programming language for cartographers and surveyors at the Moscow State University of Geodesy and Cartography are considered. As a result a new C++ programming course for undergraduate students has been developed. Cartographers and surveyors learning C++ programming are to solve tasks from the related areas of cartography and geodesy. The programming course is geared towards the needs of surveying and cartographic industry. This is the request of today to create programming courses suit...

This study reviews the problem of creating an algorithm for classifying objects in a Grid system, which will allow the automation of this process to proceed. Splitting objects into classes allows you to effectively manage the resources and processes that occur in a distributed system. Classification according to the current values of characteristics, by reference values of characteristics, with an analysis of the original causes of the result and also a modeled classification is considered. The problem of determin...

The article deals with the problem of embedded computing systems testing and debug. The embedded systems design process, actual problems and existing solutions are analyzed from this perspective. The method of testing and debug based on model-oriented record and replay of the computational process is proposed, as well as the corresponding specification model for real-time computational processes. The specification model is a modified control flow graph. The key advantage of the proposed method is an abstract defin...

Carrying out scientific experiments and field observations requires systematization, coordinated storage and possibility of online analytical processing of primary data to obtain consistent results and to discovery new knowledge. The article presents an approach to building a model-driven system based on the software platform of primary data collection and analysis. An approach to the constructing the control model of the data consolidation system based on the analysis of data description in the context of the sta...

The sequence of images received when studying a nanoobject (the induced cluster-type nanostructures) at different scales is offered to consider as result of mutual influence of factors of heredity and variability of signs on some of his initial characteristics. Features of heredity and variability of signs gives the chance of creation of hierarchical structures of formal descriptions are described, i.e. models of the nanoimages based on groups of the signs relating to various morphological and large-scale levels o...

Today retargetable and cross-platform compilers are mainstream, because variety of hardware platforms is very large, and it is required to support general-purpose programming languages for these platforms. But retargetable compiler development process has very high cost. The main criterion is development time (develop, debug and maintain time, high entrance level). Some of the most popular solutions on the market of these compilers are GCC, LLVM. Each of them contains (in implementation) platform-specific code lik...

The reprocessing of tailings is gaining importance both for economic and environmental reasons. In the case of abandoned mining waste disposals, the reprocessing of tailings constitutes an option that can be considered to fit the paradigms of the actual mineral industry challenges: circular economy and sustainability. The present study focuses on the tailings of an old embankment (Cabe?o do Pi?o) of the tungsten Panasqueira mine, in central Portugal. Although Panasqueira mine is still in operation today, it had it...

The article presents the results of aircraft positioning using the PPP method in air navigation. The PPP method is known as one of the new GNSS measurement techniques in use in aviation for precise aircraft positioning. In the article the position of the Cessna 172 aircraft was retrieved during an in-flight test conducted around the EPDE military airport in D?blin, Poland. The position of the Cessna 172 was determined and expressed in the BLh geodesic coordinates. The computations were performed in the gLAB v.4.1....

A single system of comprehensive monitoring was developed. It provides collection, processing, generalization, analysis, visualization, and storage of satellite and ground data on seismic and volcanic activity, typhoons and wildfires in a unified information environment. The principles of construction, elements and structure of the proposed system for monitoring of catastrophic phenomena and areas of their possible origin and development are presented. We describe methodological approaches to comprehensive monitor...

In celestial mechanics, when describing the dynamics of celestial bodies, as a rule, two approaches are used: numerical and analytical. The numerical approach began to develop from the middle of the 20th century, when powerful computers appeared. He gives high-precision ephemeris and the theory of rotation of celestial bodies. Analytical methods began to be used from the end of the 19th century. Thinkers of that time developed powerful mathematical tools that allowed obtaining celestial bodies coordinates with the...

The task of the work is to improve the quality of digital image processing in vision systems by developing new features based on the use of fractal theory in conjunction with fuzzy logic and the theory of fuzzy sets. At present, the systems of technical vision are actively used in many fields of science and technology. The most important part of any such system is the software, whose task is to process the information received. However, the overwhelming majority of digital image processing algorithms are based on ...

Multi-access Edge Computing (MEC) is a cloud technology that converges telecommunication and computing capabilities in radio access network. The research and standardization activities for enabling advanced mobile edge services are ongoing with diverse challenges yet to be met. A key area is the development of Application Programming Interfaces (API) that enable application to acquire mobile edge resources and simply and efficiently to manage them. Bandwidth Management Service (BWMS) is a mobile edge service that ...

The El Nino-Southern Oscillation (ENSO) plays a key role in the interannual variability of the global climate. Its prediction and recognition has been a big challenge to the atmospheric and ocean science modeling community despite significant advances in understanding, improved models, and enhanced observational networks. The present study proposes a new approach by using the support vector machines (SVM) classification model of machine learning algorithm to identify and possible predict the future ENSO events. Th...

The quality of the operation of broadband wireless computer networks is largely determined by the mechanism of an ordered centralized poll of terminal stations, called polling. The models of polling systems adequately describe the operation of broadband wireless networks under the control of Wi-Fi and Wi-MAX protocols with a centralized coordination function (PCF). Despite the complexity and high cost, the equipment supporting centralized management most effectively uses the most valuable resources of a broadband ...

The presented paper is focused on evaluation of progress stability of atherosclerotic plaques which were examined using B-MODE during at least 5 years. For this study have been examined total of 482 patients. For each patient are stored data of atherosclerotic plaque separately in left and right carotid artery. The goal of this study is to observe progress of the plaque width in transversal section. The width has been measured using diagnostic ultrasound with resolution 0.04 mm; measured width has accuracy of 0.1 ...

This paper presents a comparative study based on numerical and experimental results, regarding the single lap joints (SLJs) between pultruded glass fibre reinforced polymer (GFRP) composite elements that are bonded with epoxy adhesives. The main aspects that were investigated by experimental and numerical approaches consisted in the characteristics of the failure mechanisms and the strain distribution along the bond length at different loading stages. For the experimental program 25 specimens were prepared by vary...

Additive manufacturing is used in multiple industries to create prototypes, visual models and objects with complex geometries. Being able to fabricate an object layer by layer, additive manufacturing offers the possibility to create objects with embedded, non-assembly joints. With Fused Deposition Modeling (FDM), one of the most common and accessible 3D printing processes, minimizing joint clearance for models with non-assembly joints presents a challenge, especially in the case of consumer-grade desktop machines....

Deformation analysis represents an actual and important theme, therefore methods for improving the tracking and analysis process of deformations, both for constructions and for lands, as well as diminishing the necessary time for deformation analysis, are the main concerns for the specialists and not only. When it comes to major constructions or constructions of particular importance, deformation analysis proves to be an extremely important tool. The results of the analysis can be used in decision-making systems f...

The solution of the problem of formalization of document flow processes with the help of the proposed model of multilevel graphs of information processing has considered in the article. Despite the significant development of machine data processing technologies, the theoretical basis for their application and adaptation to the architecture of electronic document management systems is poorly developed. The model of multilevel graphs of information processing which is formalize a structure of document flow of the or...

Geoportals has become more significant and more common communication platform, used between institutions, companies and clients. The most important feature of mapping portals is sharing of spatial data to a wide audience quickly and easily. However, despite of all benefits accrued through their use, the popularity of geoportals is still too small. Probably the reason for that is the conviction of the high cost of implementation, or the lack of knowledge about the possibilities of presenting spatial data in this fo...

The Fourier Transform Infrared (FT-IR) spectroscopy is one of the suitable experimental tools for analysis of urinary calculi constituents. However, interpretation of infrared spectra for quantifying urinary calculus constituents in mixtures is difficult, requiring expert knowledge by trained technicians. The development of automated methods for determining the composition of uroconcrements is very important since it can facilitate the determination of the factors which influence the occurrence of calculi in urina...

This article presents the high risks of exploration and mining of coal deposits for coal supply to hard-to-reach regions of North Yakutia (North-east of Russia). It?s caused by a lot of factors complicating and cost-increasing all process of development of the deposits from exploration of georesource to coal combustion of consumer remote from coal mines for thousands of kilometres. Special geoinformation systems is created and developed to improve the level of technological and organizational decisions. It is base...