Nikos E Mastorakis

• Ph.D.
• Professor at Technical University of Sofia

This report presents an in-depth analysis of the practices implemented by the World Scientific and Engineering Academy and Society (WSEAS) to ensure high academic quality and integrity in its journals and conferences. By systematically reviewing quality control procedures-including pre-screening, multi-tiered peer review, and certification of revie...

Evaporation demand or potential evaporation is projected to increase almost everywhere in the world in future climate scenarios. Estimation of evapotranspiration (ET) is important for determining the agro-climatic potential of a particular region, water requirements of field crops, irrigation scheduling, and suitability of crops or varieties, which...

In the last decades, some publishers are intensively exploiting the model of open access publishing. During the last several years, studies have shown that there was a substantial increase in the number of fake publishers and hijacked journals. These cyber criminals make money by stealing the identities of legitimate journals and collecting the art...

Dynamic CMOS based transistor level designs of incrementer/decrementer circuit is presented in this work. The design of a new 8-bit decision module is first described. This is followed by elucidation of an original cascading architecture to realize larger size incrementer/decrementer circuits. From SPICE simulations corresponding to a 0.25μm CMOS p...

The aim of this research is to present a study about how pleased are the authors who publish a scientific paper with their collaboration with the publisher. A sample of 350 authors reply to a questionnaire and a statistical analysis of the results has been carried out. In addition, the quality of the peer review has been checked by sending five pap...

The aim of this research is to present a study about how pleased are the authors who publish a scientific paper with their collaboration with the publisher. A sample of 350 authors reply to a questionnaire and a statistical analysis of the results has been carried out. In addition, the quality of the peer review has been checked by sending five pap...

Whisper is an indispensable way in speech communication, especially for private conversation or human-machine interaction in public places such as library and hospital. Whisper is unvoiced pronunciation, and voiceless sound is usually considered as noise-like signals. However, unvoiced sound has unique acoustic features and can carry enough informa...

Evidence indicates a critical role of neuroinflammatory response as an underlying pathophysiological process in several central nervous system disorders, including neurodegenerative diseases. However, the molecular mechanisms that trigger neuroinflammatory processes are not fully known. The discovery of bitter taste receptors in regions other than...

Stress is a nonspecific response to a threat or noxious stimuli with resultant damaging consequences. Stress is believed to be an underlying process that can trigger central nervous system disorders such as depression, anxiety, and post-traumatic stress disorder. Though the pathophysiological basis is not completely understood, data have consistent...

Segmentation is the fundamental step in many image processing algorithms. In this paper, a simplified neuro-computing structure in feed forward form for use in segmentation of images in complex background is proposed. The work considers the formation and training a neuro-computing structure in which the pixel values of various region of the image a...

In this paper a time series of hourly equivalent noise levels acquired near the international airport of Nice, France, is analysed. Two different techniques are proposed to model and forecast the time series: deterministic decomposition and seasonal autoregressive moving average. The two models are defined and fitted on the calibration dataset. Sub...

Among the various non-destructive techniques for health monitoring in structures, the Acoustic Emission (AE) is well known in scientific literature. Ultrasonic waves emitted by the creation and propagation of cracks in concrete or Reinforced Concrete specimens are usually collected by means of ultrasonic sensors. The signals must be treated in fron...

The judgment of unvoiced and voiced sound based on sparse representation in DCT dictionary is implemented. Human pronunciation can be mainly divided into unvoiced and voiced sound. Sparse representation can represent the signal with as few coefficients as possible on a set of over-complete vectors, which can reveal the most representative features...

Three-phase power transformer is one of the most important elements in the electric power systems, and it plays a significant role in terms of energy savings. Since the efficiency standards can be expressed in terms of electrical efficiency, in an attempt to improve the transformer efficiency, in this study an enhancement of three-phase power trans...

This paper describes the design of an operative prototype based on Internet of Things (IoT) concepts for real time monitoring of various environmental conditions using certain commonly available and low cost sensors. The various environmental conditions such as temperature, humidity, air pollution, sun light intensity and rain are continuously moni...

The astrocyte-neuron lactate shunt (ANLS) hypothesis is the most widely accepted model of brain glucose metabolism. However, over the past decades, research has shown that neuronal and astrocyte plasma membrane receptors, in particular, GLUT2, Kir6.2 subunit of the potassium ATP-channel, SGLT-3 acting as glucosensors, play a pivotal role in brain g...

Book of abstracts/ Oral Presentation --------------------------------------------------------- Abstract— The present paper concerns with the analysis and the optimization of the Surface Roughness (Ra) during turning of Ti-6Al-4V ELI titanium alloy under dry cutting condition by applying both full and fractional experimental design. The main cutting...

With reference to the current issue of energy efficiency of residential buildings, the aim of this research is to analyze the possible influence of the energy performance component on the property prices formation. The study sample consists of two hundred residential units recently sold and located in the city of Bari (Italy). The implemented metho...

Background: There is a dearth and inconsistency of data on the role of the autonomic nervous system (ANS) in the development of arterial hypotension. Also, little is known about the involvement of endothelial factors in the development of this disease. The aim of the study was to investigate the role of the ANS and endothelial factors or vasoregul...

Glucoallostasis (glycemic allostasis) is a recent term and refers to the process by which blood glucose stabilization is achieved through the balancing of glucose consumption rate and release into the blood stream under the action of a variety of stressors. Maintenance of glucoallostasis involves multiple regulatory systems at the peripheral and ce...

The gut represents a diverse community of microbes, which under normal conditions protects the individual from potentially harmful invaders and other diseases that affect human and also positively modulates the functioning of all organs and systems of the organism. However, the beneficial effects of these gut commensals are reversed when conditions...

The electrodynamic strength, as forces acting between the current-carrying electric circuits are exerted as long as the currents exist, and have the tendency of deformation and displacement of the circuits. In short-circuit regimes the strength in electrical equipment becomes severe. For instance, short-circuits highly affect power transformers con...

Recurrence plot and recurrence quantification analysis are used to analyze different features of gravitational wave signals. Firstly, the appropriate delay time and embedding dimension are respectively estimated by methods of the C_C method. One dimension time series of gravitational wave is extended to high dimension phase space by employing phase...

A statistical study is implemented on the short-time spectrum of one main category of random signals. For the signals with massive and random micro-sources, a new statistic feature of the short-time amplitude spectrum is discovered, which reveals the relationship between the amplitude’s average and its standard for each frequency component. Moreove...

The term “metaplasticity” is a recent one, which means plasticity of synaptic plasticity. Correspondingly, neurometaplasticity simply means plasticity of neuroplasticity, indicating that a previous plastic event determines the current plasticity of neurons. Emerging studies suggest that neurometaplasticity underlie many neural activities and neurob...

The subject of this paper belongs to the theory of approximate metrics [23]. An approximate metric on X is a real application defined on X × X that satisfies only a part of the metric axioms. In a recent paper [23], we introduced a new type of approximate metric, named C-metric, that is an application which satisfies only two metric axioms: symmetr...

Inter symbol interference (ISI) and related distortions observed in high data rate wireless systems are mitigated using equalizers and channel estimation methods which are traditionally based on data driven tapped delay line (TDL) models. With increased fading due to mobility of transmit receive terminals, data driven schemes prove to be inefficien...

In a typical mobile environment, the varying speeds of transmit-receive pairs make traditional channel estimation methods inefficient due to continuously altering requirement of high density reference symbols. It has been largely instrumental in driving efforts to formulate innovative solutions which are appropriate for such situations. Previously,...

Full-text source at: http://www.itm-conferences.org/articles/itmconf/abs/2017/01/itmconf_amcse2017_03004/itmconf_amcse2017_03004.html - Plasma Arc Cutting (PAC) is a thermal manufacturing process used for metal plates cutting. This work experimentally investigates the influence of process parameters onto the dimensional accuracy performance of the...

A novel method for image region segmentation is proposed, which is inspired by the carrier immigration mechanism in semiconductor materials. The carrier diffusing and drifting are simulated in the proposed model, and the sign distribution of net carrier at the model’s balance state is exploited for region segmentation. The experiments have been don...

Early diagnosis and classification of long term cardiac signals are crucial issues in the treatment of heart related disorders. The available number of medical professional are not sufficient to deal with the increase patients for which design of certain machine based diagnostics tools have been accepted as a viable option. Typical Electrocardiogra...

In this paper, a time series analysis approach is adopted to monitor and predict a traffic noise levels dataset, measured in a site of Messina, Italy. In general, acoustical noise shows a high prediction complexity, since its slope is strongly related to the variability of the sources and to intrinsic randomness. In the analysed site the predominan...

Animals especially bovines and its products growth very quickly every day, so Ministry of Animal Resources pay great attention and efforts for saving bovines' products. The main goal of this work is to identify and clearly distinguish between huge different bovines and achieving high accuracy rate. This work proposed two different techniques in the...

Nowadays veterinarians pay a numerous effort to save bovines' products because of its rapid growth. The critical point in this paper is to classify and distinguish between large different groups of bovines with high degree of accuracy. This paper presents two bovine's classification models depending on J48 decision tree and Naive Bayes classifier....

Electronic circuits and systems used in mission and safety-critical applications usually employ redundancy in the design to overcome arbitrary fault(s) or failure(s) and guarantee the correct operation. In this context, the distributed minority and majority voting based redundancy (DMMR) scheme forms an efficient alternative to the conventional N-m...

Plasma Arc Cutting (PAC) is a thermal manufacturing process used for metal plates cutting. This work experimentally investigates the influence of process parameters onto the dimensional accuracy performance of the plasma arc cutting process. The cutting parameters studied were cutting speed (mm/min), torch standoff distance (mm), and arc voltage (v...

In this paper, a novel model of 3D elastic mesh is presented for image segmentation. The model is inspired by stress and strain in physical elastic objects, while the repulsive force and elastic force in the model are defined slightly different from the physical force to suit the segmentation problem well. The self-balancing mechanism in the model...

Stochastic property of speech signal is a fundamental research topic in speech analysis and processing. In this paper, multiple levels of randomness in speech signal are discussed, and the stochastic properties of unvoiced pronunciation are studied in detail, which has not received sufficient research attention before. The study is based on the sig...

http://www.naun.org/main/UPress/saed/2016/a962014-047.pdf - Optimization of cut surface quality during CNC plasma-arc cutting (PAC) of mild steel plates is presented. Using design of experiments (DOE) the optimum process parameters are estimated. The process parameters tested include cutting speed, cutting height and arc voltage. Analysis of means...

Stochastic wireless channels have significant nonlinear contents which in a restricted form are handled by traditional channel estimation and modeling approaches. The working of most of the traditional channel modeling approaches is based on the adoption of a linearized representation of the path gains which truncates a sizable portion of the conte...

The section-carry based carry lookahead adder (SCBCLA) architecture was proposed as an efficient alternative to the conventional carry lookahead adder (CCLA) architecture for the physical implementation of computer arithmetic. In previous related works, self-timed SCBCLA architectures and synchronous SCBCLA architectures were realized using standar...

Book of Abstracts/ICATA 2016-Sibiu ROM/ Abstract: Fused Filament Fabrication (FFF) is an additive manufacturing (AM) method that relies on the thermal extrusion of a thermoplastic feedstock from a mobile deposition head. FFF manufacturing has several advantages over SLS manufacturing, including lower initial machine purchases costs, ease of use (sp...

For digital system designs, triple modular redundancy (TMR), which is a 3-tuple version of N-modular redundancy is widely preferred for many mission-control and safety-critical applications. The TMR scheme involves two-times duplication of the simplex system hardware, with a majority voter ensuring correctness provided at least two out of three cop...

This article presents the design of a new asynchronous early output full adder which when cascaded leads to a relative-timed ripple carry adder (RCA). The relative-timed RCA requires imposing a very small relative-timing assumption to overcome the problem of gate orphans associated with internal carry propagation. The relative-timing assumption is...

The section-carry based carry lookahead adder (SCBCLA) topology was proposed as an improved high-speed alternative to the conventional carry lookahead adder (CCLA) topology in previous works. Self-timed and FPGA-based implementations of SCBCLAs and CCLAs were considered earlier, and it was found that SCBCLAs could help in delay reduction i.e. pave...

The section-carry based carry lookahead adder (SCBCLA) topology was proposed as an improved high-speed alternative to the conventional carry lookahead adder (CCLA) topology in previous works. Self-timed and FPGA-based implementations of SCBCLAs and CCLAs were considered earlier, and it was found that SCBCLAs could help in delay reduction i.e. pave...

This paper analyzes the merits and demerits of global weak-indication self-timed function blocks versus local weak-indication self-timed function blocks, implemented using a delay-insensitive data code and adhering to 4-phase return-to-zero handshaking. A self-timed ripple carry adder is considered as an example function block for the analysis. The...

N-modular redundancy (NMR) is commonly used to enhance the fault tolerance of a circuit/system, when subject to a fault-inducing environment such as in space or military systems, where upsets due to radiation phenomena, temperature and/or other environmental conditions are anticipated. Triple Modular Redundancy (TMR), which is a 3-tuple version of...

This paper analyzes the merits and demerits of global weak-indication self-timed function blocks versus local weak-indication self-timed function blocks, implemented using a delay-insensitive data code and adhering to 4-phase return-to-zero handshaking. A self-timed ripple carry adder is considered as an example function block for the analysis. The...

The section-carry based carry lookahead adder (SCBCLA) topology was proposed as an improved high-speed alternative to the conventional carry lookahead adder (CCLA) topology in previous works. Self-timed and FPGA-based implementations of SCBCLAs and CCLAs were considered earlier, and it was found that SCBCLAs could help in delay reduction i.e. pave...

N-modular redundancy (NMR) is commonly used to enhance the fault tolerance of a circuit/system, when subject to a fault-inducing environment such as in space or military systems, where upsets due to radiation phenomena, temperature and/or other environmental conditions are anticipated. Triple Modular Redundancy (TMR), which is a 3-tuple version of...

UWB systems are continuously affected by narrow band interference (NBI) emanating from traditional sources for which its mitigation continues to be a challenging issue. This is more so if the channels are considered to be non-linear which in reality is the actual scenario. NBI suppression is an essential element for achieving appropriate quality of...

The present paper aims to test hypothesis of twin deficits in North Africa countries. For that, we apply statistical and econometric approaches on North Africa panel data. The period of analyze is 1991-2011 and data are collected from IMF data base. Results given by statistical analysis suggest a positive correlation between the two deficits, 0.987...

A Rayleigh fading channel is nonlinear in nature. Therefore channel modeling techniques can be more accurately represented by nonlinear stochastic models. In this paper, we consider a block faded Single Input Single Output (SISO) system. A Nonlinear Autoregressive Moving Average (NARMA) filter is designed to equalize the received signal. A double f...

The dangerous effect of acoustical noise on health, both auditory and non-auditory, is largely documented in literature. The study of noise problem and the development of several predictive models are very important issues in cities and areas in which relevant noise sources are present. A model based on threshold exceedances is suitable since a gre...

Full paper at: http://www.iaras.org/iaras/filedownloads/ijap/2016/015-0001.pdf Fused filament fabrication (FFF) is a process that produces 3D printed models by addition of solid material. All printed prototypes should have best accuracy to satisfy all requirements. In the current research was investigated if the parameter of fused filament temperat...

In previous work, fast neural networks (FNNs) for information extraction was presented. The operation of these networks relies on performing cross-correlation between the input patterns and the weights of processing elements in the frequency domain. In this paper, a new strategy to accelerate this approach is introduced. Such strategy applies the c...

E-government has a lack of investment over financial and organizational perspectives regards to the mechanism provided for supporting government services. There are many key challenges such as integrated database centers, interoperability, and quality of service. The proposed framework has great enhancement impact over investment including financia...

Sustainable operation of electric railway systems represents a significant purpose nowadays in the development of high power and high speed locomotives and trains. At present, high speed electric vehicles mostly work with three-phase induction motors or three-phase synchronous motors as traction motors. The two electric machine types have different...

In recent times, communication technologies have evolved at a brisk rate. 3G and 4G networks have already been widely deployed. However, with increase in user number and applications, alternative strategies in the form of 5G systems have been devised. Thus, it is desirable to have communication systems which can provide low error levels with minimu...

Background; The using of clinical decision support systems (CDSSs) may improve chronic disease management, which requires recurrent visits to multiple health professionals, ongoing disease control, treatment monitoring, and patient behavior modification. The objective of this survey is to determine if these CDSSs improve the processes of chronic ca...

Over the past decades, low-calorie sweeteners (LCSs) have emerged as the main source of sweetening food products and beverages. Evidences suggest mixed effects of LCSs intake. In addition, there is a paucity of data on long-term health outcomes of LCSs intake as well as their usefulness in certain groups of the population (e.g., pregnant women, chi...

Chaotic sequences are effectively used for secure communication. Generation of chaotic sequences continues to be an evolving area. Recently, stress has been given to the generation of orthogonal chaotic codes. In this paper, a chaotic spreading sequence based direct sequence/spread spectrum (DSSS) communication system is proposed. Here, a logistic...

Full paper at: http://www.inase.org/library/2015/crete/bypaper/AME/AME-23.pdf Abstract: Additive Manufacturing (AM), also called 3D Printing, is a process where a three dimensional physical part is created by printing or adding very thin layers of material on top of each other, until the part is complete. The parts are created with a computer aided...

Full paper at: http://www.inase.org/library/2015/crete/bypaper/AME/AME-15.pdf

In this paper we introduce two concepts of generalized measurability for set-valued functions, namely φ-µ-total-measurability and φ-µ-measurability relative to a non-negative function φ : P0.(X)× P0(X)→[0,+∞) and a non negative set function µ:A → [0,+∞) and present some relationships between them. We also define different types of convergences for...

The present paper aims to measure and analyze labour market rigidity. For that we choose model of WS/PS model in wage bargain form and we complete the estimation by WS version and VAR model. Then main results show that Tunisian labour market is rigid. Facing to unemployment, real productivity and real wage lag1 changes, WS/PS gives that real wage i...

A method is proposed to estimate the background in video sequences with dense moving objects. The velocity field is estimated by optical flow to determine the image areas occupied by moving objects. The background is estimated by an efficient averaging process within the regions excluding the moving objects, which overcomes the foreground-occluding...

Error commission, detection, and correction are the products of the activities of a complex neural network referred to the error monitoring and processing system (EMPS) diffusely located in different brain regions. High-precision error coupling is the hallmark of EMPS functioning that is the result of effective neural processing and monitoring of e...

Stochastic wireless channels are abundant with nonlinear contents. Most of the traditional channel modeling approaches adopts a linearized representation which removes a sizable portion of the contents. It results in lowering of the quality of service (QOS) and degrades system performance. To consider the non-linear components in the channel, bette...

Wireless transmission in severe fading environments require suitable channel equalization methods for true recovery of the transmitted signal. Designing an equalizer, however, depends on the channel conditions. Traditional methods of channel modeling rely upon certain tools including tapped delay line (TDL) aided by Autoregressive (AR), Moving Aver...

Full text at: http://www.wseas.us/e-library/conferences/2015/Salerno/IMAS/IMAS-14.pdf Abstract: Fused Filament Fabrication (FFF) is a manufacturing technique commonly used for 3D Printing. In order to satisfy functional requirements, FFF prototypes should have acceptable accuracy. In the current study the process parameters effects influencing the...

Reliable and safe operation of a coal-fired power plant is strongly linked to freshwater resources, and environmental problems related to water sources and wastewater discharge are challenges for power station operation. In this study, an evaluation on the basis of a wastewater thermal pollution vector is reported for the environmental impact of re...

The aim of research — analysis of interconnections between content of glucose in integrate capillaceous blood of people with different functional states (attitude of rest and mental work in fasting state, also in time of Oral Glucose Tolerance Test) and factors of using alcohol (once and monthly doses, rates of using), continuance of a period sober...

Approximation of functions of a complex variable by various finite-dimensional aggregates is an important problem not only in constructive function theory and approximation but also in the theoretical background of direct approximate methods for functional equations. This problem has been well studied for the case of functions defined on standard c...

Full text at: http://www.inase.org/library/2015/books/bypaper/MMMCE/MMMCE-10.pdf