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Number of results: 46
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Abstract

A novel dual mode logic (DML) model has a superior energy-performance compare to CMOS logic. The DML model has unique feature that allows switching between both modes of operation as per the real-time system requirements. The DML functions in two dissimilar modes (static and dynamic) of operation with its specific features, to selectively obtain either low-energy or high-performance. The sub-threshold region DML achieves minimum-energy. However, sub-threshold region consequence in performance is enormous. In this paper, the working of DML model in the moderate inversion region has been explored. The near-threshold region holds much of the energy saving of subthreshold designs, along with improved performance. Furthermore, robustness to supply voltage and sensitivity to the process temperature variations are presented. Monte carol analysis shows that the projected near-threshold region has minimum energy along with the moderate performance.
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Abstract

In the last few years, a great attention was paid to the deep learning Techniques used for image analysis because of their ability to use machine learning techniques to transform input data into high level presentation. For the sake of accurate diagnosis, the medical field has a steadily growing interest in such technology especially in the diagnosis of melanoma. These deep learning networks work through making coarse segmentation, conventional filters and pooling layers. However, this segmentation of the skin lesions results in image of lower resolution than the original skin image. In this paper, we present deep learning based approaches to solve the problems in skin lesion analysis using a dermoscopic image containing skin tumor. The proposed models are trained and evaluated on standard benchmark datasets from the International Skin Imaging Collaboration (ISIC) 2018 Challenge. The proposed method achieves an accuracy of 96.67% for the validation set .The experimental tests carried out on a clinical dataset show that the classification performance using deep learning-based features performs better than the state-of-the-art techniques.
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Abstract

In this paper a review on biometric person identification has been discussed using features from retinal fundus image. Retina recognition is claimed to be the best person identification method among the biometric recognition systems as the retina is practically impossible to forge. It is found to be most stable, reliable and most secure among all other biometric systems. Retina inherits the property of uniqueness and stability. The features used in the recognition process are either blood vessel features or non-blood vessel features. But the vascular pattern is the most prominent feature utilized by most of the researchers for retina based person identification. Processes involved in this authentication system include pre-processing, feature extraction and feature matching. Bifurcation and crossover points are widely used features among the blood vessel features. Non-blood vessel features include luminance, contrast, and corner points etc. This paper summarizes and compares the different retina based authentication system. Researchers have used publicly available databases such as DRIVE, STARE, VARIA, RIDB, ARIA, AFIO, DRIDB, and SiMES for testing their methods. Various quantitative measures such as accuracy, recognition rate, false rejection rate, false acceptance rate, and equal error rate are used to evaluate the performance of different algorithms. DRIVE database provides 100% recognition for most of the methods. Rest of the database the accuracy of recognition is more than 90%.
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Abstract

The paper introduces a topology mutation – the novel concept in Moving Target Defense (MTD). MTD is a new technique that represents a significant shift in cyber defense. Traditional cybersecurity techniques have primarily focused on the passive defense of static networks only. In MTD approach cyber attackers are confused by making the attack surface dynamic, and thus harder to probe and infiltrate. The emergence of Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technology has opened up new possibilities in network architecture management. The application of combined NFV and SDN technologies provides a unique platform for implementing MTD techniques for securing the network infrastructure by morphing the logical view of the network topology.
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Abstract

Waste management is a challenging problem for most of the countries. The current waste segregation and the collection method are not efficient and cost-effective. In this paper, a prototype is presented for smart waste management. It is also capable of waste segregation at the ground level and providing real-time data to the administrator. Impact and cost analysis of the deployment of smartbin is also presented considering one ward of Ahmedabad Municipal Corporation. It is clear from that deployment of this smartbin will save about 40% of the current expenditure for that ward.
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Abstract

In this paper, a new 11T SRAM cell using FinFET technology has been proposed, the basic component of the cell is the 6T SRAM cell with 4 NMOS access transistors to improve the stability and also makes it a dual port memory cell. The proposed cell uses a header scheme in which one extra PMOS transistor is used which is biased at different voltages to improve the read and write stability thus, helps in reducing the leakage power and active power. The cell shows improvement in RSNM (Read Static Noise Margin) with LP8T by 2.39x at sub-threshold voltage 2.68x with D6T SRAM cell, 5.5x with TG8T. The WSNM (Write Static Noise Margin) and HM (Hold Margin) of the SRAM cell at 0.9V is 306mV and 384mV. At sub-threshold operation also it shows improvement. The Leakage power reduced by 0.125x with LP8T, 0.022x with D6T SRAM cell, TG8T and SE8T. Also, impact of process variation on cell stability is discussed.
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Abstract

The paper presents a concept of a control system for a high-frequency three-phase PWM grid-tied converter (3x400 V / 50 Hz) that performs functions of a 10-kW DC power supply with voltage range of 600÷800 V and of a reactive power compensator. Simulation tests (in PLECS) allowed proper selection of semiconductor switches between fast IGBTs and silicon carbide MOSFETs. As the main criterion minimum amount of power losses in semiconductor devices was adopted. Switching frequency of at least 40 kHz was used with the aim of minimizing size of passive filters (chokes, capacitors) both on the AC side and on the DC side. Simulation results have been confirmed in experimental studies of the PWM converter, the power factor of which (inductive and capacitive) could be regulated in range from 0.7 to 1.0 with THDi of line currents below 5% and energy efficiency of approximately 98.5%. The control system was implemented in Texas Instruments TMS320F28377S microcontroller.
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Abstract

Usually, cellular networks are modeled by placing each tier (e.g macro, pico and relay nodes) deterministically on a grid. When calculating the metric performances such as coverage probability, these networks are idealized for not considering the interference. Overcoming such limitation by realistic models is much appreciated. This paper considered two- tier twohop cellular network, each tier is consisting of two-hop relay transmission, relay nodes are relaying the message to the users that are in the cell edge. In addition, the locations of the relays, base stations (BSs), and users nodes are modeled as a point process on the plane to study the two hop downlink performance. Then, we obtain a tractable model for the k-coverage probability for the heterogeneous network consisting of the two-tier network. Stochastic geometry and point process theory have deployed to investigate the proposed two-hop scheme. The obtained results demonstrate the effectiveness and analytical tractability to study the heterogeneous performance.
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Abstract

This work presents a theoretical study for the distribution of nanocomposite structure of plasmonic thin-film solar cells through the absorber layers. It can be reduced the material consumption and the cost of solar cell. Adding nanometallic fillers in the absorber layer has been improved optical, electrical characteristics and efficiency of traditional thin film solar cells (ITO /CdS/PbS/Al and SnO2/CdS/CdTe/Cu) models that using sub micro absorber layer. Also, this paper explains analysis of J-V, P-V and external quantum efficiency characteristics for nanocomposites thin film solar cell performance. Also, this paper presents the effect of increasing the concentration of nanofillers on the absorption, energy band gap and electron-hole generation rate of absorber layers and the effect of volume fraction on the energy conversion efficiency, fill factor, space charge region of the nanocomposites solar cells.
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Abstract

In this fast-changing environmental condition, the effect of fossil fuel in vehicle is a significant concern. Many sustainable sources are being studied to replace the exhausting fossil fuel in most of the countries. This paper surveys the types of electric vehicle’s energy sources and current scenario of the onroad electric vehicle and its technical challenges. It summarizes the number of state-of-the-art research progresses in bidirectional dcdc converters and its control strategies reported in last two decades. The performance of the various topologies of bidirectional dc-dc converters is also tabulated along with their references. Hence, this work will present a clear view on the development of state-of-the-art topologies in bidirectional dc-dc converters. This review paper will be a guide for the researchers for selecting suitable bidirectional traction dc-dc converters for electric vehicle and it gives the clear picture of this research field.
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Abstract

To overcome the detrimental influence of α impulse noise in power line communication and the trap of scarce prior information in traditional noise suppression schemes , a power iteration based fast independent component analysis (PowerICA) based noise suppression scheme is designed in this paper. Firstly, the pseudo-observation signal is constructed by weighted processing so that single-channel blind separation model is transformed into the multi-channel observed model. Then the proposed blind separation algorithm is used to separate noise and source signals. Finally, the effectiveness of the proposed algorithm is verified by experiment simulation. Experiment results show that the proposed algorithm has better separation effect, more stable separation and less implementation time than that of FastICA algorithm, which also improves the real-time performance of communication signal processing.
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Abstract

Accurate network fault diagnosis in smart substations is key to strengthening grid security. To solve fault classification problems and enhance classification accuracy, we propose a hybrid optimization algorithm consisting of three parts: anti-noise processing (ANP), an improved separation interval method (ISIM), and a genetic algorithm-particle swarm optimization (GA-PSO) method. ANP cleans out the outliers and noise in the dataset. ISIM uses a support vector machine (SVM) architecture to optimize SVM kernel parameters. Finally, we propose the GA-PSO algorithm, which combines the advantages of both genetic and particle swarm optimization algorithms to optimize the penalty parameter. The experimental results show that our proposed hybrid optimization algorithm enhances the classification accuracy of smart substation network faults and shows stronger performance compared with existing methods.
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Abstract

Operational Transresistance Amplifier (OTRA) has been a topic of great interest recently. OTRA has proved itself to be an appropriate device for the analog applications. As MOS scaling suffers from various problems, carbon nanotube field effect transistor (CNTFET) has came into light as one of the brightest alternative for FET (Field Effect Transistors) based devices. This work has introduced a new CNTFET based OTRA which is capable of realising inverse low pass filter using two OTRAs and few passive elements. CNTFET based OTRA has been designed and simulated at 10nm technology node. The working ability of the designed model has been conformed using HSPICE simulation. It is compared with conventional CMOS based OTRA. The comparative analysis has revealed improvement in various performance parameters. The paper also presents how change in number of carbon nanotube in CNTFETs in OTRA circuit affects the transresistance gain and input impedance. The optimized results are also discussed to improve transresistance gain and input impedance. The paper also dealt with the realisation of inverse low pass filter using proposed CNTFET based OTRA.
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Abstract

To avoid of manipulating search engines results by web spam, anti spam system use machine learning techniques to detect spam. However, if the learning set for the system is out of date the quality of classification falls rapidly. We present the web spam recognition system that periodically refreshes the learning set to create an adequate classifier. A new classifier is trained exclusively on data collected during the last period. We have proved that such strategy is better than an incrementation of the learning set. The system solves the starting–up issues of lacks in learning set by minimisation of learning examples and utilization of external data sets. The system was tested on real data from the spam traps and common known web services: Quora, Reddit, and Stack Overflow. The test performed among ten months shows stability of the system and improvement of the results up to 60 percent at the end of the examined period.
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Abstract

An application specific integrated design using Quadrature Linear Discriminant Analysis is proposed for automatic detection of normal and epilepsy seizure signals from EEG recordings in epilepsy patients. Five statistical parameters are extracted to form the feature vector for training of the classifier. The statistical parameters are Standardised Moment, Co-efficient of Variance, Range, Root Mean Square Value and Energy. The Intellectual Property Core performs the process of filtering, segmentation, extraction of statistical features and classification of epilepsy seizure and normal signals. The design is implemented in Zynq 7000 Zc706 SoC with average accuracy of 99%, Specificity of 100%, F1 score of 0.99, Sensitivity of 98% and Precision of 100 % with error rate of 0.0013/hr., which is approximately zero false detection.
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Abstract

Utilization of drones is going to become predominated in cellular networks as aerial base stations in order to temporary cover areas where stationary base stations cannot serve the users. Detecting optimal location and efficient number of drone-Base Stations (DBSs) are the targets we tackle in this paper. Toward this goal, we first model the problem using mixed integer non-linear programming. The output of the proposed method is the number and the optimal location of DBSs in a two-dimension area, and the object is to maximize the number of covered users. In the second step, since the proposed method is not solvable using conventional methods, we use a proposed method to solve the optimization problem. Simulation results illustrate that the proposed method has achieved its goals.
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Abstract

The objective of this paper is a review of data on reconstruction of the Pleistocene palaeogeography (environment) and stratigraphy based on studies of karst sites in the Świętokrzyskie (Holy Cross) Mountains. Although the number of known Pleistocene karst sites in this region is small, the investigations of them have played a crucial role in a research of the Pleistocene. The study of the Kozi Grzbiet site provided the first evidences for new climatostratigraphy and classification of glaciations in Poland. The explanation of genesis of cryogenic calcite crystals discovered in Chelosiowa Jama-Jaskinia Jaworznicka cave system started a new direction of palaeoenvironmental reconstructions of the last glacial period. Kadzielnia palaeontological site was one of the first Early Pleistocene fossil assemblages in karst studied in Poland, whereas Raj cave provided abundant palaeontological and archaeological material from the Last Glacial. Other sites are of less scientific importance, however some of them can be used in education and popularisation of geosciences. Small number of already studied sites does not exclude discoveries of next sites of high scientific importance.
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Abstract

The paper presents characteristics of the Pleistocene sediments in the western part of the Holy Cross Mountains. They are subdivided into four complexes and their stratigraphic setting is referred to the updated scheme for the Pleistocene of Poland. The Preglacial Complex includes fluvial sediments characteristic for its lack of Scandinavian material. Sediments of three main glaciations (Nidanian, Sanian 1 and Sanian 2) within the South Polish Complex, are referred also as the South Polish Glaciations. The oldest of these glaciations (Nidanian) is separated from the middle glaciation (Sanian 1) by sediments of the Podlasian Interglacial, represented by clay at the Kozi Grzbiet Cave that contains faunal remains and record of the Brunhes/Matuyama palaeomagnetic boundary. During the middle (Sanian 1) and youngest glaciation (Sanian 2), the Holy Cross Mountains were almost completely covered by the Scandinavian ice sheet, forming glacial deposits separated by fluvial series of the Ferdynandovian Interglacial. The Middle Polish Complex begins with sediments of the Mazovian Interglacial, represented by a pollen record from the Zakrucze site. They are followed by deposits of periglacial and fluvial origin of the Liwiecian Glaciation, Zbójnian Interglacial, Krznanian Glaciation and Lublinian Interglacial. The following glaciation (Odranian) is represented by the youngest glacial deposits that document presence of the Scandinavian ice-sheet in the westernmost part of the Holy Cross Mountains. The North Polish Complex is composed of a climatic warming (Eemian Interglacial) and cooling (Vistulian Glaciation), and is represented by valley and periglacial deposits. The last cooling of the Pleistocene is recorded in faunal remains in the Raj Cave.
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Abstract

According to the current state of research five sand-gravel accumulation levels of Quaternary age are visible in the morphology of the western part of the Holy Cross Mountains, within the Wierna Rzeka, Hutka and Bobrza river valley systems and the lower stretches of the Biała Nida and Czarna Nida river valleys. Two upper levels (V and IV) correspond to valleys formed during the Odranian Glaciation-Saalian, MIS6 and its reccesional phases under the influence of proglacial and extraglacial waters beyond the extent (to the east) of the maximal ice-sheet limit of this glaciation, reaching to the present-day Leśnica-Gnieździska-Łopuszno line. Two lower levels (III and II) are terraces that were typically formed during the climatic conditions thatprevailed during Vistulian stadials. Sands and gravels of the three upper levels (V−III) contain numerous debris flow deposits and cryoturbation structures documenting periglacial conditions during their accumulation. The lowermost level (I) is a typical Holocene floodplain.
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Abstract

This paper presents the Late Glacial stage of the development of the Białe Ługi peatland in the southern Holy Cross Mountains, based on a comprehensive palaeoenvironmental data. A complex analysis of palynology, Cladocera, sed imentology, geochemistry and 14C dating were used. Organic deposition was initiated during the Oldest Dryas. The sedimentary record of the aquatic and terrestrial ecosystems reflects considerable difference between cooler (Oldest, Older and Younger Dryas) and warmer phases (Břlling and Allerřd). Periods of intensified interaction between aeolian processes and peatland are related to stages of disappearing vegetation and changes in aquatic invertebrate communities. We therefore suggest that peatlands were created as a result of local lithological-structural, tectonic, hydrogeological and morphological conditions, and the peatland development rate was largely influenced by changing climatic conditions, which determined local vegetation development, intensity of denudation processes and water level changes. The results validate significance of selection and use of several methods, as well as value of biogenic deposits from the Białe Ługi peatland as archives of past climate change in the Małopolska Upland. Relatively stable water conditions and uninter rupted biogenic sedimentation in the Late Glacial that were provided by the geological structure and relief suggest the studied peatland is a leading one in the region.
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Abstract

The Vistulian decline was a period of rapid environmental events. The authors correlated ages of the last Scandinavian Ice Sheet limits in northern Poland with ages of prominent events adapting the conditions of periglacial environment of Central Poland in response to the Late Vistulian climate warming. Ages from previous thematic geological and palaeogeographical studies were collected. The approach used indicates that despite methodological uncertainties and sometimes inconsistency of ages, it is especially helpful in timing of first warming signals (ca. 19–18 cal ka BP) and establishing of environmentally bipartite 3 millennia of the Oldest Dryas in the extraglacial zone. Abrupt warming at the onset of the Bølling-Allerød is well registered in biotic and abiotic archives available from Central Poland and remains in agreement with the large recession of the southern ice sheet margin.
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Abstract

The article is focused on the most recent investigations of glaciotectonic structures in high escarpment exposures of the Vistula valley from Dobrzyń to Kuzki in the western part of the Płock Basin. Deformations involve Neogene and occasionally the Lower Pleistocene deposits and they are not expressed as landforms. Structural investigations and analysis of archival geological data provided new information on the origin of large-scale shear structures. Results obtained are clearly contrary to the concept of Brykczyński (1982) regarding valley-side glaciotectonics in the Płock Basin. An emergence of the extensive zone of serial thrust structures of significant amplitude (up to 100–150 m) was found to have not been controlled by a palaeovalley. A driving mechanism is interpreted as a gravity spreading in front of ice sheets advancing from north-northeast during the South Polish Complex (Dorst-Elsterian).
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Abstract

Luminescence dating is based mainly on the dosimetric properties of quartz and feldspar. These minerals are among the most popular found on Earth, resulting in the possibility of using luminescence methods in practically any environment. Currently, quartz remains the best recognized mineral in terms of dosimetric properties, particularly with regards to results obtained for quartz grains, which are regarded as being the most reliable in luminescence dating. Supporters of luminescence methods are constantly growing, however, these groups do not always have sufficient knowledge to avoid even the most basic of issues that may be encountered overall – from the process of sampling through to the awareness of what a single luminescence result represents. The present paper provides an overview of several practical aspects of luminescence dating such as correct sampling procedures and all necessary information regarding the calculation of the dose rate and equivalent dose with particular reference to potential problems that occur when the age of the sample is being determined. All these aspects are crucial for obtaining a reliable dating result, on the other hand, they remain a potential source of uncertainty.
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Abstract

Results of a geomorphologic study as well as radiocarbon and pollen analyses of sediments in small basins of the Jasło-Sanok Depression (Western Carpathians) are summarised. Floors of these basins, carved in soft shale-sandstone Krosno Beds, are covered with channel fluvial deposits and oxbow-lake sediments with lake chalk and peat accumulated in the Late Vistulian and Holocene. Since the early Atlantic Phase (ca 8,400–7,900 BP) the apparent acceleration of overbank (flood) deposition intermitting the peat accumulation is observed. The plant succession includes the Late Glacial (pre-Allerød, Allerød and Younger Dryas) with coniferous park forests, through mixed deciduous forests of the Holocene with elm, hazel, oak and lime as well as spruce-elm forests with alder in wetlands, up to present-day hornbeam forests (Tilio-Carpinetum of various types) and extra-zonal Carpathian beech forests (Dentario-Glandulosae- Fagetum). Abies alba (fir) is frequent in both these association types. First evidences of synanthropic plants that prove presence of prehistoric man appeared in the Subboreal Phase. The oldest radiocarbon date 13,550±100 BP (Gd-7355) [16,710–16,085 b2k], from a bottom part of the Humniska section is probably overestimated. This is indicated by palynological data, which suggest attribution of this section to the older Allerød. Small thickness of gravel blanket from the Plenivistulian termination and the beginning of the Late Vistulian, as well as large areas devoid of weathering and solifluction covers indicate that during the Plenivistulian weathering processes and removal of silt-clay material predominated in the basins. In that time the deflation was among important processes, which is proved by deflation troughs, faceted cobbles and thick covers of the Carpathian type of loess. The Besko Basin has pre-Vistulian tectonic foundation, while landforms of its floor are of erosion-degradation origin and formed during the last Scandinavian glaciation. In the Holocene the basin floors were overbuilt with fluvial deposits up to 8 m thick.
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