bluuebunny/crossref_metadata_2025 huggingface dataset:
Power Efficient Communication for Joint Detection Receivers in Rician Channels
Authors: Kumar V. Vignesh , Giridhar K.
Published: July 2016

In a multipoint to point link, where multiple streams from geographically separated points co-existing in time and frequency are jointly detected, the relative powers at which the signals are received play an important role in deciding the sum rate. Unlike Rayleigh fading, where decreasing the power of any of the streams will result only in decrease in the sum rate, Rician fading exhibits an interesting behavior where one can actually improve the sum rate by decreasing the power of one or more of the transmitted streams. This gives rise to the possibility of power efficient communications under Rician channel conditions. In this paper, the authors discuss a power control scheme where the receiver, based on the present received powers and k-factor, feeds back the optimal powers to be transmitted so that the total transmitted power is minimized without any loss in the sum rate. It can be shown that by employing such a power control scheme, considerable amount of power can be saved on the transmit side, paving way to greener communications, for LoS or near LoS links.
Analysis on Interference Impact of Wi-Fi on Digital Terrestrial Television Broadcasting
Authors: Ancans Guntis , Bobrovs Vjaceslavs , Ancans Arnis , Stankevicius Evaldas
Published: July 2016

Transition from Analogue Terrestrial Television Broadcasting to Digital Terrestrial Television Broadcasting (DTTB) in the 470-862 MHz band made available amount of spectrum so-called digital dividend for other services i.e. 790-862 MHz band (800 MHz) to mobile service. Recently the 694-790 MHz band (700 MHz) was also allocated to mobile service in ITU Region 1. Spectrum allocated to a broadcasting service but not used locally is called as TV white spaces (TVWS). It is possible to introduce TVWS services in 470-790 MHz band under the condition that other services in this band already operating, or planned in the country and in neighboring countries, are adequately protected and this use does not violate the current ITU Radio Regulations. TVWS under some conditions locally could be used for mobile communication systems e.g. unlicensed Wireless Fidelity (Wi-Fi) using cognitive radio. As TVWS are located in the UHF band, the use of TVWS can provide significantly better coverage and wall penetration inside buildings than 2.4 GHz and 5 GHz range Wi-Fi frequencies. The exact amount of available spectrum for TVWS at any location will be dependent upon each country national situation e.g. DTTB planning configuration, other services use in the band. In case of deploying Wi-Fi in the TVWS the interference impact of Wi-Fi on DTTB has to be taken into account. The aim of this paper is to analyze the interference impact of Wi-Fi on DTTB. In this paper the interference occurring probability in DTTB receiver was evaluated by using Spectrum Engineering Advanced Monte-Carlo Analysis Tool (SEAMCAT).
The Design of LTE System
Authors: Dixit Saurabh , Katiyar Himanshu
Published: July 2016

There has been a paradigm shift in the field of mobile communication, with an overwhelming increase in data usage. As more and more users are migrating to Smart-phones, the amount of data being transmitted has increased manifold times. However, such huge amount of data and signal propagation is bound to be detrimental to the ecological balance. Long Term Evolution (LTE), due to its flexibility, and backward compatibility has emerged as the network of choice for 4G and beyond. In this article, the significance of core technologies for LTE network is highlighted, along with the inherent advantage of reducing the energy consumption of cellular network. An Energy Efficient design of LTE is proposed which blends the technologies proposed by 3GPP such as adaptive OFDMA with that of MU-MIMO.
Transition to ISO 15189 : 2012 for Cytopathology Laboratories Part 3
Authors: Vavoulidis Eleftherios , Archondakis Stavros , Nasioutziki Maria , Oustambasidou Ourania , Daniilidis Angelos , Dinas Konstantinos , Loufopoulos Aristotelis
Published: July 2016

Modern cytopathology has advanced from the point when conventional Pap testing was adequate enough for medical diagnosis thanks to the implementation of the latest Laboratory Diagnostics. No matter how well-structured a cytopathology laboratory may be, it is still subjected to potential risks that could dramatically affect its services. Risk identification, evaluation and management via a Quality Control Plan can become a powerful tool for cytopathology laboratories wishing to maintain or/and enhance the quality of their diagnostic services. The authors present their experience on the implementation of such a risk analysis and control system covering all the necessary parameters and issues that should be addressed. Also, a hypothetical structure for a risk analysis is presented with useful guidance associated with cytological laboratories conducting morphological and molecular examinations. Finally, a mobile health solution is proposed that, if designed properly, could further optimize and harmonize risk management strategies globally.
A Suggested Curriculum in Career Education to Develop Business Secondary Schools Students' Career Knowledge Management Domains and Professional Thinking
Authors: Fouda Faten Abdelmagied Elsoudy
Published: July 2016

The current research aimed at designing a proposed curriculum in career education for business secondary schools students and measuring its effectiveness on developing career knowledge management domains and professional thinking skills. To achieve the desired goal, the researcher applied the system approach in designing the suggested career education curriculum, the developmental research methodology for developing the instructional materials and media, and the quasi-experimental design to measure the effectiveness the proposed curriculum on a sample of the third grade business secondary school students in Egypt. The suggested curriculum contains four main stages/phases: 1) career knowledge generation; 2) career knowledge organization; 3) career knowledge utilization; and 4) career knowledge distribution. These phases were integrated into one system to develop both career knowledge management skills and professional thinking among the target sample. The units of the curriculum were designed in an interactive way according to the principles of the blended-units approach that concentrates on knowledge and knowledge applications for achieving career requirements needed to joining 21st century business and administration jobs. A sample of 50 students enrolled in a business secondary school were selected randomly and divided equally into two groups: the experimental group (n= 25) and the control group (n= 25). The researcher developed two main instruments: 1) an achievement test; and 2) a professional thinking scale. The achievement test included two parts: 1) measuring the professional knowledge, and 2) performance measuring of the skills of designing professional portfolio. In addition, a rubric was used to evaluate the production of the professional portfolio. The findings revealed that the suggested curriculum was effective in developing both career knowledge management domains and professional thinking skills; as there were significant statistical differences between the two groups in favor of the experimental group. A set of educational recommendations were suggested.
Investigating the Use of Web 2.0 Technologies and their Presence in Saudi Government Agencies' Websites
Authors: Altayar Mohammed
Published: July 2016

Government agencies in both developed and developing countries have started using social media to provide content and services. The aim of this study is to investigate the use of social media in Saudi government agencies. It adopts a quantitative approach. The study shows that Saudi government agencies are aware of social media and they use them for different purposes. The study argued that government agencies with less engagement with the public are less likely to use social media. Government agencies tend to publish the same content in different social media. Moreover, information dissemination and improving communication with the public were the main motivations for using social media. In terms of enablers, the study shows that awareness of the public about the importance of social media usage was an important issue. Regarding the challenges, lack of dedicated resources such as budget and specialized staff were the main challenges. The study contributes to the literature by addressing issues related to motivation, factors influenced the decision to adopt social media, enablers and barriers.
Rolling-Contact Hardening Evaluated by Indentation
Authors: Schmidová Eva , Kaya Utku , Schmid Michal , Culek Bohumil
Published: July 2016

The operational degradation of surface layers due to a rolling contact process was simulated for Hadfield steel by a special testing rig. A specific limited state based on cumulative depletion of plasticity was achieved.Precise evaluation of the surface layer's mechanical parameters is necessary for a service life prediction. Very low depth of localized dislocation hardening process doesn ́t allow the standard mechanical testing. The comparative instrumented indentation tests using Vickers and cylindrical indenter were used for evaluation of defined stage of surface degradation process. The intensity and reach of deformation hardening are partially limiting for particular methodology. The yield stress of surface layers was estimated according to an analytical model of uniaxial vs. indentation plastic flow ratio.
High Temperature Nanoindentation Testing of Amorphous SiC and B4C Thin Films
Authors: Čtvrtlík Radim , Tomastik Jan , Schovánek Petr
Published: July 2016

Amorphous silicon carbide (a-SiC) and boron carbide (a-B4C) thin films were deposited using reactive magnetron sputtering of SiC and B4C target, respectively. Nanoindentation tests performed up to 450 °C in air were performed to explore and compare their hardness and elastic modulus.Hardness of a-B4C film decreases at smaller rate in comparison to a-SiC film up to 450 °C. Similarly, elastic modulus value of B4C is more stable with temperature than that of a-SiC.
Determination of DC06+ZE Sheet Crack Cause
Authors: Kejzlar Pavel , Pilvousek Tomáš , Tregler Michal
Published: July 2016

The present work deals with determination of the cause of crack occurring in a part of car body manufactured from deep-drawing sheet. UHR-SEM, EDS, EBSD and measurement of microhardness were used for evaluation of the structure, local deformation and crack formation mechanism. A material analysis discovered foreign particles in the material. These particles were identified as MgAl2O4 with BCC lattice. The occurrence of these hard particles led to local stress concentration, decrease in mechanical strength and sheet breach due to tensile stress during deformation.
Adhesion Additive Influence on Polyamide Nanopolymer Composite Properties
Authors: Habr Jiří , Bobek Jiří , Bĕhálek Luboš , Seidl Martin
Published: July 2016

In recent years there are efforts to use polymer nanofibers and their properties in polymer composites. The aim of such efforts is to develop composites with nanofibers fillers which would be able into a great extend to take advantage of any unique properties of polymer nanofibers. Such area of research belongs into the research project whose part is also to incorporate nanofibers and nanoparticles into composite with thermoplastic matrix. The important part of research represents also finding the suitable additives to ensure sufficient adhesion between filler and polymer matrix which is crucial for the final composite properties.
The Attempt of New Approach to Evaluate Surface Integrity
Authors: Malec Jiří , Červinka Filip , Blažíček Dominik , Suoknuuti Janne
Published: July 2016

Machined surface of hard steel parts like gears, bearings, camshafts etc. is full of local imperfections which are commonly described in terms of surface integrity. This surface integrity is usually quantified with the level of residual stresses or amplitude of Barkhausen noise signal for instance. The contribution introduces parameter called Sum of Effective Residual Stresses (SERS) to describe the level of surface damage after grinding. Experimental data obtained by X-Ray Diffraction (XRD) and Barkhausen Noise Analysis (BNA) methods of ground gears are shown. The way to use SERS approach for experimental determination of penetration depth of Barkhausen signal in steels is proposed, too.
Micro-Hardness of Irradiated Polyamide
Authors: Manas David , Ovsík Martin , Maňas Miroslav , Stanek Michal , Hylová Lenka , Šenkeřík Vojtech , Opočenský Michal
Published: July 2016

The influence of beta radiation on the changes in the structure and selected properties (mechanical and thermal) was proved. Using high doses of beta radiation for glass fiber filled polyamide (PA) and its influence on the changes of micromechanical properties of surface layer has not been studied in detail so far. The specimens of glass fiber filled PA were made by injection moulding technology and irradiated by low doses of beta radiation (0, 132, 165 and 198 kGy). The changes in the microstructure and micromechanical properties of surface layer were evaluated using WAXS and instrumented microhardness test. The results of the measurements showed change some in micromechanical properties (indentation hardness) when high doses of beta radiation are used.
Young’s Modulus of Alumina Particles Reinforced Metal-Matrix Composite
Authors: Haušild Petr , Kovářík Ondřej , Havlíková Kristýna , Thomasová Martina
Published: July 2016

Young’s modulus of alumina particles reinforced pure Al-matrix composite is characterized by different methods: the pulse-echo ultrasound method, static three point bending, resonant bending and continuous multicycle measurement by instrumented indentation. Dependency of apparent Young’s modulus on loading amplitude was observed and attributed to the local mechanical properties of both phases, especially to the development of internal damage (local plasticity and particle cracking).
Impact of Climatic Ageing on the Basic Mechanical Properties of Viscoelastic Sealants
Authors: Minster Jiří , Šašek Petr
Published: July 2016

The aim of the research presented here was to assess the influence of climatic loading on the basic mechanical properties of polymer sealants, from the viewpoint of their application in creating and repairing outdoor mosaics. Six promising sealants were selected for the measurements. They were tested in their native state and also after four different model types of physical-chemical ageing were applied. We used a combination of ultra-violet radiation with the influence of enhanced temperature, moisture and also soaking in water and freezing. The Hysitron TI 750D TriboIndeterTM system, equipped with a Berkovich indenter, was used for tests. The basic mechanical characteristics were measured using the Basic QS Trapezoid quasi-static mode. Time-dependent properties of the sealants were assessed by the indentation creep method. The results have confirmed that microindentation technique offers a suitable methodology for assessing changes in the basic mechanical time-dependent properties of the tested sealants due to photo-degradation processes and climatic effects.
Nanoindentation Assessed Fracture Toughness of Cement Paste
Authors: Němeček Jiří , Hrbek Vladimír
Published: July 2016

This paper deals with fracture properties of microlevel components of hydrated cementpaste. Determination of fracture energy and fracture toughness for quasi-brittle materials hasbecome a challenge for many years on both macro- and micro-scales. Limited number of quantitative data can be found in the literature for the micro-scale. This work uses energetic approach and decomposition of work of indentation into plastic and other parts. Based on simplified assumptions fracture energy and fracture toughness are calculated for individual microstructural phases of cement paste with the aid of nanoindentation, statistical deconvolution and fracture mechanics.
Measuring Techniques for Retroreflectivity Levels of Small Signs
Authors: Vik Michal , Kolčavová Sirková Brigita , Viková Martina , Duchoňová Lucie , Pechová Marcela
Published: July 2016

Collisions between vehicles and pedestrians are a significant problem, and substantial evidence indicates that the problem is closely linked with low illumination. A less expensive approach to enhancing the conspicuity of pedestrians involves using retroreflective material – material that has been engineered to passively reflect light back in the direction of its source. In a Textile faculty of TU Liberec was developed microscopic method to research the affecting factors textile thin bands retroreflectivity [1]. This work has been done through the use of several quality tools allowing studying different phenomena such as effect of color and technology on retroreflectivity levels.
Polarimetric Sensing Technique for Textile Material
Authors: Vik Michal , Khan Nayab , Viková Martina , Founě František
Published: July 2016

The identification and measuring of geometrical dimensions of very small objects including textile is the biggest achievement of the image processing techniques. Not only the analysis of the basic structure of yarn like hairiness, thickness and number of twist but also the external structural analysis like twist parameters and linear density co-efficient is possible with outstanding approach of image analysis new techniques. Dyed polyester samples by using different dyestuffs were examined with the polarized light with the help of optical light microscopy. It was observed that the dyestuffs possess strong dichroism and the relationship between dichroism and the concentration of dyestuff was examined. Dark field and Bright field illuminations together with imaging polarimetry are compared in terms of depth of field tolerance and image quality. Experiments show that passive imaging polarimetry illumination is superior in terms of depth of field tolerance and contrast allowing significant improvement of textile structure investigation.
The Possibilities of Evaluating the Yield Strength in the Heat Affected Zones of a Weld through Indentation
Authors: Hanus Petr , Schmidová Eva
Published: July 2016

The research focuses on elastic-plastic behaviour of welded joints of materials which are commonly used in both constructional practice and the automotive industry. The examined welded joints are oriented to a common constructional S355 and a modern high-strength steel DOMEX 700MC.The main tool for the assessment of the elastic-plastic response was the methodology based on the instrumented penetration testing with the use of a cylindrical indenter. The indentation tool was applied into narrow zones of welded boundaries. These zones represent critical areas of welded constructions because of a changing structure and different mechanical properties than the basic material possesses. The indentation data were recalculated to the mechanical properties in shear with the help of Hencky ́s hypotheses about material behaviour. The correctness of the used methodology was verified by a tensile test. The aim of the work is to determine optimal methods for defining a yield strength and to find a hardening trend in the zones. The comparison of these steels revealed different changes due to the welding process. A substantial decrease of the yield strength of Domex700MC was observed, as a contrary to a stable, or partially increased, yield strength of the S355 steel. Structural analyses revealed a different material response of the evaluated steels, according to a different hardness in the heat affected zone.
Effect of Actual Indenter Shape on the Results of Spherical Nanoindentation
Authors: Čech Jaroslav , Haušild Petr , Kovářík Ondřej , Škereň Marek
Published: July 2016

Actual shape of the diamond spherical indenter of nominal radius 20 μm was investigated in this study. 3D reconstruction was performed by atomic force microscope and by the method of stereopair using SEM images of the tip taken under several different angles. The results were compared with the shape obtained indirectly by the calibration performed on specimens with known Young’s modulus. It was found that lower effective values of tip radius for the small penetration depths are caused by the irregular geometry of contact between indenter and specimen surface. With increasing penetration depth the radius increased to the theoretical values and it decreased again for high penetration depths. The stress-strain curves were determined using corrected effective indenter radius.
Serrated Plastic Flow of Various Metallic Glasses during Nanoindentation
Authors: Huráková Mária , Csach Kornel , Miškuf Jozef , Juríková Alena , Demčák Štefan , Ocelík Václav , de Hosson Jeff T.M.
Published: July 2016

Nanoindentation experiments were executed on amorphous metallic ribbons made of Fe40Ni40B20, Cu47Ti35Zr11Ni6Si1 and Zr65Cu17.5Ni10Al7.5 that differ in microhardness and glass forming ability. The individual serrated plastic flow events were analyzed in a wide range of the loading rates. In the individual pop-in events of the load-displacement (P-h) curve the contributions of plastic deformation (Δhpl) were calculated depending on the loading rate and the alloy composition. It is concluded that the contribution of the serrated plastic deformation flow varies with the composition of the alloy. The highest plastic deformation for the individual pop-ins was observed for Zr-based metallic glasses.
The Influence of Microstructure, Heat-Treatment and Type of Crystal Lattice of Iron Aluminides on Coefficient of Thermal Expansion
Authors: Švec Martin
Published: July 2016

The iron aluminides seem to be very perspective materials for high temperature structural application. They have many advantages, but unfortunately also some negative properties – e.g. sharp drop in strength above 600°C or limited ductility at room temperature. These disadvantages can be reduced by alloying of binary alloy by other elements.Present work deals with a study of coefficient of thermal expansion (CTE). It was investigated the influence of microstructure and heat-treatment on the values of CTE. Secondary, it was studied the possibilities, how to determine phase transition temperatures from CTE curves. Influence of type of iron aluminides lattice on CTE values was also examined as well as the influence of addition of alloying elements into binary iron aluminides.
Application of Laser-Ultrasound for Characterization of Plasma-Sprayed Ceramics
Authors: Koller Martin , Seiner Hanuš S. , Sedlák Petr , Kotlan Jiří , Ctibor Pavel , Mušálek Radek , Landa Michal
Published: July 2016

Laser-based resonant ultrasound spectroscopy (RUS) method was applied to measure elastic constants of a porous calcium titanate coating manufactured by water-stabilized plasma-spraying (WSP). To enhance the reflectivity of the polished surface of this material for the lasers applied at RUS measurements, a thin coating of sodium metasilicate (waterglass) was used. It is discussed how the metasilicate affects the acoustic properties of the underlying porous material and experimentally shown that such a surface treatment enables the characterization of the structural processes in these materials at elevated temperatures.
Influence of Deposition Parameters on the Properties of Nanocomposite Coatings Prepared by Cathodic Arc Evaporation
Authors: Béger Miroslav , Sondor Jozef , Sahul Martin , Zacková Paulína , Haršáni Marián , Čaplovič Ľubomír
Published: July 2016

The article deals with the influence of different deposition parameters on the selected properties of AlCrN/Si3N4 nanocomposite coatings. Bias voltage, cathodes currents and working gas pressure were changed during the deposition process. All coatings were deposited using Lateral Rotating Cathodes (LARC®) process that belongs to the group of cathodic arc evaporation PVD technologies. In comparison with the typical cathodic arc evaporation process which usually uses planar targets the LARC® process utilizes rotational cathodes that are positioned close to each other. Nanohardness, Young's modulus, thickness and residual stresses were determinated in order to evaluate the influence of deposition parameters on these coatings properties
Tribological Properties of Magnetron Sputtered Amorphous Silicon Carbide and Silicon Carbonitride Coatings
Authors: Tomastik Jan , Čtvrtlík Radim
Published: July 2016

The tribological properties of magnetron sputtered amorphous silicon carbide (a-SiC) and silicon carbonitride coatings (a-SiCN) with thickness of 2.2 and 3.4 µm were investigated. Samples were additionally annealed at temperature of 700°C or 900°C in air. Progressive load scratch tests were performed on the annealed samples as well as on the as deposited ones. An acoustic emission signal was detected during all tests using the sample holder with embedded sensor of our own design.
Results indicate no change in wear resistance of SiCN sample after high temperature exposure up to 900°C, unlike in the tests of SiC coatings. Detection of acoustic emission generated during the scratch test proved to be a significant improvement for the coating evaluation.
Bias and 1/f Noise Degradation Modeling of 90 nm n-Channel MOSFETs Induced by Hot Carrier Stress
Authors: Totsuka Takuya , Aoki Hitoshi , Abe Fumitaka , Arai Yukiko , Todoroki Shunichiro , Kazumi Masaki , Higashino Masashi , Kobayashi Haruo
Published: July 2016

The goal of this research is to model the drain current and 1/f noise degradation characteristics of n-channel MOSFETs. In this paper, we present the implementation of hot carrier degradation into drain current equations of BSIM4 model. We show simulation results of the DC drain current degradation, and then 1/f noise voltage density simulation results affected by the drain current degradation. We have extracted BSIM4 model parameters extensively with the measured data including I-V and 1/f noise measurement of our TEGs. Especially for 1/f noise degradation characterizations, the input referred noise has been calculated after extracting the 1/f noise parameter degradations.
A High Precision IGBT Macro-Model for Switching Simulations
Authors: Kazumi Masaki , Aoki Hitoshi , Arai Yukiko , Todoroki Shunichiro , Totsuka Takuya , Kobayashi Haruo
Published: July 2016

In this research, a novel SPICE model of an Insulated-Gate-Bipolar-Transistor (IGBT), which is often used to handle high power signals in automotive electrical circuits, has been developed. The model consists of basic SPICE elements. Thus, it can be used in any SPICE-compatible simulators without any source code modification. This paper presents the results of DC, small signal AC, and transient characteristics considering the temperature dependence by using the proposed IGBT macro-model for SPICE. In addition, turn-on and -off time verifications are presented by using a switching test circuit provided by an IGBT manufacturer.
Evaluation of Radio-Photoluminescence Spectra of Copper-Doped Phosphate Glass Dosimeter Irradiated with Ionized Particles
Authors: Parajuli Raj Kumar , Kada Wataru , Kawabata Shunsuke , Matsubara Yoshinori , Miura Kenta , Yokoyama Akihito , Haruyama Moriyoshi , Sakai Makoto , Hanaizumi Osamu
Published: July 2016

A radio-photoluminescence (RPL) dosimeter with a copper-ion luminescent center was fabricated to evaluate its response in ionized particle detection. A focused proton microbeam with varying energies up to 3 MeV and heavy ions of 490 MeV osmium (Os) were employed along with X-rays to evaluate its performance in micrometer-scale radiation monitoring. The response to ionized particles was evaluated under focused proton beam irradiation where the peak wavelength differed from that obtained under X-ray irradiation. Two peaks were observed under Os irradiation where the secondary-generated particles and photons have a significant effect on the dosimeter. The results suggest that the fabricated RPL dosimeter with copper luminescence center could be used to estimate the irradiation effect of primary ionized particles separately from the effects of secondary particles, photons, and environmental background radiation.
First Observation of Non-Resonant X-Ray Magnetic Diffraction for Multilayers
Authors: Shimoyama Hidefumi , Osawa Tokiko , Watanabe Hiromi , Suzuki Kosuke , Sakurai Hiroshi , Ito Masahisa
Published: July 2016

Co/Pd magnetic multilayers have been prepared by using a sputtering method. Lattice distances and magnetic hysteresis curves have been measured by X-ray diffraction (XRD) measurements and magnetization measurements using a vibrating sample magnetometer (VSM). The XRD measurements have shown that the samples with thinner Pd layers have shorter lattice distances, and the VSM measurements have shown that the samples of thinner Co and thicker Pd layers are closer to those of perpendicular magnetic anisotropy. We have applied the X-ray magnetic diffraction method to the Co/Pd multilayer for the first time and have succeeded in observing a change in the X-ray diffraction intensities by the reversal of the magnetization direction.
Effect of Humidity and Bias on the Size of Nanostructures Fabricated by STM Anodization and its Application to Patterns
Authors: Yin You
Published: July 2016

In this paper, the effect of humidity and sample bias on the size of nanostructures fabricated by STM anodization on a 3 nm-thick Ti film was investigated by random nano-arrays. 3.5 V and 4 V bias were applied to samples at a relative humidity of ~30% while 3.5 V, 4 V and 4.5 V were applied to samples at a relative humidity of ~43%. According to the cross section analyses, dots scattered randomly on surfaces became larger and higher as the bias increased at a constant relative humidity or as the relative humidity increased at the same bias. Two complicated patterns were fabricated by running a program in which the movement of STM tip and the sample bias were defined.
Photoluminescence and Electroluminescence Properties of (Ca,Sr)TiO3:Er
Authors: Kyômen Tôru , Seki Miyu , Hanaya Minoru , Takashima Hiroshi
Published: July 2016

Powder samples of (Ca,Sr)TiO3:Er were prepared by a solid-state reaction method. Photoluminescence due to f-f transitions of Er3+ was not induced by band-gap excitation of (Ca,Sr)TiO3 but by f-f transitions of Er3+. An electroluminescent device in which thin films of Ca0.6Sr0.4TiO3:Er and SnO2:Sb are stacked alternately was prepared by sol-gel and spin-coating methods. Very weak electroluminescence due to f-f transition of Er3+ was observed in the device.
Synthesis and Ionic Conductivity of KAlSi3O8
Authors: Furusawa Shinichi , Minami Yohei
Published: July 2016

In this study, KAlSi3O8 was synthesized by a solid-phase reaction at 900, 1000 and 1100 °C, using K2CO3, Al2O3 and SiO2 as the starting materials. The powder X-ray diffraction profile of the compound thus prepared was confirmed to contain a mixture of crystalline and glass phases. In addition, a higher sintering temperature of greater than 1000 °C possibly led to the decrease in the crystalline phase. From the temperature dependence of dc conductivity, activation energies for ionic transport were estimated to be 0.79–0.84 eV. The frequency-dependence of the real part of electrical conductivity suggests that the mechanism of ionic transport in the dispersion region possibly depends on the crystallinity of KAlSi3O8.
A Typical MOSFET Modeling Procedure for RF Analog Circuit Design
Authors: Aoki Hitoshi , Kobayashi Haruo
Published: July 2016

This paper presents a theoretical yet practical device targeting method to extract typical model parameters of MOSFET devices on wafer for RF analog integrated circuit design. This method employs skewing algorithms with model parameters of existing typical device which are selected by using inter-lot process electrical test parameters. Although this technique can be applied for both n-channel and p-channel MOSFETs, only n-channel devices could be prepared for our experiments in this research. To demonstrate the plausibility of this method, a cascode amplifier is designed to simulate frequency characteristic of S21 with this method.
Demolding Moment Calculation for Injected Parts with Internal Trapezoidal Thread
Authors: Haragâş Simion , Negrean Iuliu , Pop Dumitru , Buiga Ovidiu , Rusu Florina
Published: July 2016

At the final step of the injection process (of a plastic product with cavities) when the part is on the point to be ejected the adhesion phenomena occurs between the core and the plastic part. The mold adhesion effect has a significant influence on the mold design ejection system and over the whole process. This paper presents a computation methodology of the demolding moment for two cases of plastic injected parts with internal trapezoidal thread. Knowing the value of this moment offer us the possibility to adopt the right design solution of the ejector system and of the entire mold. As further work the author will try to validate this method through a set of practical experiments.
The Effect of Cross-Linking on Nano-Mechanical Properties of Polyamide
Authors: Ovsik Martin , Manas David , Manas Miroslav , Stanek Michal , Reznicek Martin
Published: July 2016

Radiation crosslinking of polyamidu 6 (PA 6) is a well-recognized modification of improving basic material characteristics. Radiation, which penetrated through specimens and reacted with the cross-linking agent, gradually formed cross-linking (3D net), first in the surface layer and then in the total volume, which resulted in considerable changes in specimen behaviour. This research paper deals with the possible utilization of irradiated PA6. The material already contained a special cross-linking agent TAIC (5 volume %), which should enable subsequent cross-linking by ionizing β – radiation (15, 30 and 45 kGy). The effect of the irradiation on mechanical behavior of the tested PA 6 was investigated. Material properties created by β – radiation are measured by nanoindentation test using the DSI method (Depth Sensing Indentation). Hardness increased with increasing dose of irradiation at everything samples; however results of nanoindentation test shows increasing in nanomechanical properties of surface layer. The highest values of nanomechanical properties were reached radiation dose of 45 kGy, when the nanomechanical values increased by about 95%. These results indicate advantage cross-linking of the improved mechanical properties.
Electrochemical Codeposition of UHMWPE Biopolymer into Cobalt Matrix for Biomedical Applications
Authors: Benea Lidia , Dănăilă Eliza
Published: July 2016

The aim of this work was to obtain hybrid Co/UHMWPE composite biocoatings reinforced by UHMWPE (ultra high molecular weight polyethylene) biopolymer microparticles in the cobalt matrix, by electro-codeposition technique, with possibilities to use them as biomaterials. UHMWPE was selected as surface modifier element, due to its high biocompatibility and low coefficient of friction being used in many biomedical applications. Cobalt is already used in biomedical implants as cobalt – chromium alloys. The obtained coatings were investigated in terms of surface morphology (scanning electron microscopy - SEM), chemical composition and inclusion percentage (energy dispersive X-ray spectroscopy - EDX), roughness and microtopography (atomic force microscopy - AFM), coating thickness and microhardness. The SEM morphologies of electrodeposited pure cobalt and Co/UHMWPE composite biocoatings, show differences due to UHMWPE biopolymer particles incorporation in the cobalt matrix. The inclusion of UHMWPE microparticles increases with increasing the UHMWPE concentration in the electrolyte as was demonstrated by EDX investigations. The addition of the UHMWPE biopolymer microparticles to the deposition bath led to an increase of the roughness of hybrid coatings comparatively with pure cobalt coating obtained under the same conditions. The coating thickness of the electroplated surfaces as were observed by cross sectional scanning electron micrographs confirm higher adhesion strength of the coatings on the stainless steel support.
Surface Analyses of Arboform Samples
Authors: Plavanescu Mazurchevici Simona , Nedelcu Dumitru , Bellisario Denise , Carausu Constantin
Published: July 2016

Due to the global warming and diminishing petroleum oil reserves the conversion of biomass in useful biodegradable materials represent a tremendous need in terms of economic and environmental problem. During the last years, enormous effort have been sustained by the researchers who tried to develop and improve green (recyclable, biocompatible, and biodegradable) materials from renewable resources strengthening this way the global sustainability. Following this need a new material Arboform – „liquid wood“, that meets all the above conditions was developed by a team of german researchers appearing shortly on the market. This material can be processed like any other plastic material, so no need changing in terms of technological equipment. Since the injection molding is the most widely used process in manufacturing polymer products, unavoidable surface quality problems appear. In order to obtain a clear image of surface sample are analyzed the inherent properties of the used material, injection parameters and conditions using a Talysurf CLI 2000 profilometer. The equipment is able to perform high-accuracy measurements of the surface topography for Arboform L, V3 Nature (A-LW) and Arboform L, V3 Nature Reinforced with Aramid Fibers (A-LWAF) samples. The experimental research was achieved by means of the Taguchi experiment plan, with 6 input parameters (injection pressure, melt temperature, cooling time, screw displacement injection time and injection angle) each of them having two levels of variation. In case of 90 degrees angle injection (samples from 1 and 2 experiments) the dispersion roughness (Ra) measured on east-west direction is lower (26.6% for A-LW and 23.7% respectively for A-LWAF) compared with the roughness measurement on north-south direction. At 0 degrees angle injection the dispersion had the same trend (lower for east-west direction) of the A-LWAF 4 and 6 samples and higher in the east-west direction for 3 and 5 samples of A-LW material studied.
Evaluation of Mechanical Properties of Surface Layer Injection Molded Polypropylene by Nanoindentation Test
Authors: Manas David , Manas Miroslav , Ovsik Martin , Stanek Michal , Stoklasek Pavel , Fiala Tomas , Hylova Lenka
Published: July 2016

The influence of beta radiation on the changes in the structure and selected properties (mechanical and thermal) polymers were proved. The use of low doses of beta radiation for polypropylene and its influence on the changes of micro, macro mechanical properties was thoroughly studied. The specimens of polypropylene were made by injection molding technology and irradiated by low doses of beta radiation (0, 15 and 33 kGy). The changes in the microstructure and micromechanical properties of surface layer were evaluated using WAXS and instrumented nano hardness test. The results of the measurements showed considerable increase in mechanical properties (indentation hardness, indentation elastic modulus) when the beta radiation are used.
Lymphoepithelioma-like carcinoma of the bladder: A case report.
Authors: Stamatiou Konstantinos , Christopoulos Georgios , Tsavari Aikaterini , Koulia Kallirhoe , Manoloudaki Kassiani , Vassilakaki Thivi
Published: July 2016

type of low differentiated carcinoma of the nasopharyngeal region characterized by marked infiltration of lymphocytes in the area involved by tumor. However, carcinomas with this peculiar morphologic feature have been also described in various anatomic locations and they are generally designated «lymphoepithelioma-like carcinomas». Those of the urinary bladder are uncommon as they account of 0.4%-1.3% of all bladder carcinomas. They may coexist with the conventional urothelial carcinoma. Given their rarity, there is poor information regarding their behaviour. Here we present a new case of lymphoepithelioma-like carcinoma in the bladder and we discuss its characteristics and prognosis.
Safety and efficacy of percutaneous nephrolithotomy in the Galdakao - Modified Supine Valdivia position: A prospective analysis
Authors: Quaresima Luigi , Conti Alessandro , Vici Alexia , Tiroli Marco , Cantoro Daniele , Rreshketa Admena , Principi Emanuele , Tallè Matteo , Moroni Luca , Yehia Mahmoud , Muzzonigro Giovanni
Published: July 2016

Objective: Aim of the present study was to evaluate the safety and efficacy of Percutaneous Nephrolithotomy (PCNL) in the Galdakao- Modified Supine Valdivia (GMSV) position in order to predict operative time, stone-free rate and onset of complications taking into account comorbidity, stone-related parameters and anatomic upper urinary tract abnormalities. Material and methods: A prospective evaluation of patients who underwent to PCNL in GMSV position for renal stones > 2 cm, from January 2009 to February 2015 was performed. According to the technique, upper urinary tract abnormalities, stone chemical and morphological characteristics, and patients' history were matched with operative outcome, in terms of stone-free, intervention time and incidence of perioperative complications. Results: Seventy-two cases were collected; mean operative time was 105 minutes (DS 41): staghorn stones and the presence of comorbidity resulted statistically significant variables. The complication-rate resulted in line with data showed in literature: hyperpyrexia and hemorrhage were the more frequently complications found. The overall stone-free was reached in 48 patients (67%), and it was influenced by patients’ anatomic abnormalities. Conclusions: In the treatment of renal stones, PCNL may be a safe and effective choice; nevertheless, patients’ anatomic abnormalities or staghorn-stones may influence the outcomes. Thus, a prospective study with a larger population is needed to verify our outcomes.
Abstract book of the XXI Congresso Nazionale della Società Scientifica FADOI, Roma, 14-17 maggio 2016
Authors: Campanini Presidente: M.
Published: July 2016

Abstract book of the XXI Congresso Nazionale della Società Scientifica FADOI, Roma, 14-17 maggio 2016.
Meningitis with polymerase chain reaction for varicella zoster positivity in cerebrospinal flid of a young immunocompetent adult
Authors: Gupta Pooja , Ranjan Rajeev , Agrawal C. S. , Muralikrishnan K , Dave Nikhil , Rana Davinder Singh
Published: July 2016

Meningitis caused by varicella zoster virus (VZV) is quite rare among young immunocompetent adults though immunocompromised patients are often seen to be affected by reactivation of VZV presenting with primary clinical features of dermatomal rashes and neurological sequelae. Here, we report the clinical scenario of a young, healthy male who had presented with fever, headache, and onset of dermatomal rashes later than the fever and was eventually diagnosed to be a case of VZV meningitis. We would like to highlight the fact that even young immunocompetent patients though rarely, might contract VZV meningitis and clinicians should have a high index of suspicion and keen eyes to catch the more obvious features of VZV infection on complete physical examination and must not harbor any reservations in ordering polymerase chain reaction for VZV DNA or initiating aggressive antiviral therapy.
Role of ankle foot orthosis in improving locomotion and functional recovery in patients with stroke: A prospective rehabilitation study
Authors: Sankaranarayan H. , Gupta Anupam , Khanna Meeka , Taly Arun B. , Thennarasu K.
Published: July 2016

Objective: To study role of ankle foot orthosis (AFO) in improving locomotion and functional recovery after stroke. Setting: Neurological Rehabilitation Department of a university research tertiary hospital. Patients and Methods: AFO and activity based rehabilitation. Main Outcome Measures: Distance (meters) covered during the 6-minute walk test (6MWT) and speed (meter/second) during the 10-meter walk test. Functional abilities assessed using Functional Independence Measure (FIM®). Results: Twenty-six patients (21 male) with stroke (mean duration 196.7 days, range 45–360 days) and mean age of 41.6 years (range 18–65 years, standard deviation [SD] 12.5) were included. Fourteen had right hemiplegia. The mean length of stay in the unit was 26.5 days (range 18–45 days, SD 5.5). All patients had equinus deformity with spastic foot drop and were provided with AFO. Walking endurance with 6MWT was 90 m on admission (without AFO). At discharge, it improved to 174 m with AFO and 121 m without AFOs (P < 0.001-with and without AFO at discharge). Walking speed improved from 0.4 m/s (admission) to 0.51 m/s with AFO, P = 0.004 and 0.45 m/s without AFO, P = 0.015) at discharge. Nine patients (34.6%) had clinically important difference-minimal clinically important difference (>0.16 m/s speed gain; >50 m endurance gain) at discharge. The mean FIM® score on admission was 84.3 ± 18.6. At discharge FIM® improved to 101.9 ± 13.7 (P < 0.001). Conclusions: Use of AFOs improve gait parameters significantly in only one-third stroke patients in the study when combined with activity-based inpatient-rehabilitation.
Leer de otra manera: la distant reading y la didáctica de la literatura en el entorno digital
Authors: Garcia Rivera Gloria , García-Manso Angélica
Published: July 2016

Se revisa el concepto de distant reading y las teorías de Franco Moretti. Son analizadas sus repercusiones en orden a la didáctica de la literatura –en lo que supone de cambio de foco y de inversión de metodologías– que hasta ahora se centraban en lo singular de la obra literaria, para dar paso a una percepción cuantitativa y que atiende más al reconocimiento de patrones textuales que al estudio propio de la lectura intensiva.
Modelos de educación literaria en el moderno sistema escolar
Authors: Núñez Gabriel
Published: July 2016

En este trabajo abordamos los distintos modelos que hemos utilizado en el moderno sistema escolar para educar literaria y estéticamente a los escolares de la España contemporánea. Desde el modelo Retórico que bebe en el mundo clásico y se impone hasta las primeras décadas del siglo XX al actual modelo “lector”, que parte de las teoría de la recepción, pasando por el modelo Histórico-Positivista que se sirve de las Historias de la literatura, y por el modelo Institucionista que se focalizaba en la lectura interpretativa.
Lectura en tres etapas
Authors: Carrillo Pimentel Margot , Carrillo Torea Carmen Virginia
Published: July 2016

Se expone una experiencia trabajo de promoción de la lectura de textos literarios, realizado con dos grupos de estudiantes y un grupo de maestros de escuelas bolivarianas de las zonas rurales del estado Trujillo, Venezuela, realizada por el Laboratorio de Investigación “Arte y Poética”, de la Universidad de los Andes, Núcleo Trujillo, Venezuela. Tras una reflexión teórica sobre el tema de la lectura, se describe la estrategia seguida: el diagnóstico, el desarrollo de los talleres y la evaluación de los resultados, para llegar a conclusiones finales.
Metáfora y creatividad lingüística
Authors: Martínez Ezquerro Aurora
Published: July 2016

La tradicional memorización de una lista de figuras retóricas para su identificación en el comentario literario de las clases de Lengua Castellana y Literatura resulta improductiva y desvirtúa el sentido primordial que aportan estos recursos de la lengua al discurso. Ante esta situación, es preciso enseñar al alumno a comprender su estructura formal y su valor expresivo puesto que le dotará de un instrumento fundamental para analizar estos recursos del lenguaje en cualquier contexto.

 