Search results for: magnetically controlled growing rods.

Authors: Abbas Ghanbari-Malidarreh

Abstract:

In most wheat growing moderate regions and especially in the north of Iran climate, is affected grain filling by several physical and abiotic stresses. In this region, grain filling often occurs when temperatures are increasing and moisture supply is decreasing. The experiment was designed in RCBD with split plot arrangements with four replications. Four irrigation treatments included (I0) no irrigation (check); (I1) one irrigation (50 mm) at heading stage; (I2) two irrigation (100 mm) at heading and anthesis stage; and (I3) three irrigation (150 mm) at heading, anthesis and early grain filling growth stage, two wheat cultivars (Milan and Shanghai) were cultured in the experiment. Totally raining was 453 mm during the growth season. The result indicated that biological yield, grain yield and harvest index were significantly affected by irrigation levels. I3 treatment produced more tillers number in m2, fertile tillers number in m2, harvest index and biological yield. Milan produced more tillers number in m2, fertile tillers in m2, while Shanghai produced heavier tillers and grain 1000 weight. Plant height was significant in wheat varieties while were not statistically significant in irrigation levels. Milan produced more grain yield, harvest index and biological yield. Grain yield shown that I1, I2, and I3 produced increasing of 5228 (21%), 5460 (27%) and 5670 (29%) kg ha-1, respectively. There was an interaction of irrigation and cultivar on grain yields. In the absence of the irrigation reduced grain 1000 weight from 45 to 40 g. No irrigation reduced soil moisture extraction during the grain filling stage. Current assimilation as a source of carbon for grain filling depends on the light intercepting viable green surfaces of the plant after anthesis that due to natural senescence and the effect of various stresses. At the same time the demand by the growing grain is increasing. It is concluded from research work that wheat crop irrigated Milan cultivar could increase the grain yield in comparison with Shanghai cultivar. Although, the grain yield of Shanghai under irrigation was slightly lower than Milan. This grain yield also was related to weather condition, sowing date, plant density and location conditions and management of fertilizers, because there was not significant difference in biological and straw yield. The best result was produced by I1 treatment. I2 and I3 treatments were not significantly difference with I1 treatment. Grain yield of I1 indicated that wheat is under soil moisture deficiency. Therefore, I1 irrigation was better than I0.

Keywords: anthesis, grain yield, irrigation, supplementary, Wheat.

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Authors: Ajab Khan Kasi, Muhammad Waseem Ashraf, Jafar Khan Kasi, Shahzadi Tayyaba, NitinAfzulpurkar

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This paper presents the development of low cost Nano membrane fabrication system. The system is specially designed for anodic aluminum oxide membrane. This system is capable to perform the processes such as anodization and electro-polishing. The designed machine was successfully tested for 'mild anodization' (MA) for 48 hours and 'hard anodization' (HA) for 3 hours at constant 0oC. The system is digitally controlled and guided for temperature maintenance during anodization and electro-polishing. The total cost of the developed machine is 20 times less than the multi-cooling systems available in the market which are generally used for this purpose.

Keywords: Anodic aluminum oxide, Nano-membrane, hardanodization, mild anodization, electro-polishing.

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Authors: Irina Severin, M. Caramihai, K. Chung, G. Tasca, T. Park

Abstract:

The current study has investigated the ageing phenomena of silica optical fibres in relation to water activity which might be accelerated when exposed to a supplementary energy, such as microwaves. A controlled stress by winding fibres onto accurate diameter mandrel was applied. Taking into account that normally a decrease in fibre strength is induced in time by chemical action of water, the effects of cumulative reagents such as: water, applied stress and supplementary energy (microwave) in some cases acted in the opposite manner. The microwave effect as a structural relaxation catalyst appears unexpected, even if the overall gain in fibre strength is not high, but the stress corrosion factor revealed significant increase in certain simulation conditions.

Keywords: optical fibres, mechanical testing, aging, microwave, structural relaxation.

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Authors: Z.A. Jaffery, Vinay Kumar Chandna, Sunil Kumar Chaudhary

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This paper present a MATLAB-SIMULINK model of a single phase 2.5 KVA, 240V RMS controlled PV VSI (Photovoltaic Voltage Source Inverter) inverter using IGBTs (Insulated Gate Bipolar Transistor). The behavior of output voltage, output current, and the total harmonic distortion (THD), with the variation in input dc blocking capacitor (Cdc), for linear and non-linear load has been analyzed. The values of Cdc as suggested by the other authors in their papers are not clearly defined and it poses difficulty in selecting the proper value. As the dc power stored in Cdc, (generally placed parallel with battery) is used as input to the VSI inverter. The simulation results shows the variation in the output voltage and current with different values of Cdc for linear and non-linear load connected at the output side of PV VSI inverter and suggest the selection of suitable value of Cdc.

Keywords: DC Blocking capacitor, IGBTs, PV VSI, THD.

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Authors: M. Nassereddine, A. Hellany, M. Nagrial, J. Rizk

Abstract:

The demand on High voltage (HV) infrastructures is growing due to the corresponding growth in industries and population. Many areas are being developed and therefore require additional electrical power to comply with the demand. Substation upgrade is one of the rapid solutions to ensure the continuous supply of power to customers. This upgrade requires civil modifications to structures and fences. The civil work requires excavation and steel works that may create unsafe touch conditions. This paper presents a brief theoretical overview of the touch voltage inside and around substations and uses CDEGS software to simulate a case study.

Keywords: Earth safety, High Voltage, AC interference, Earthing Design.

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Authors: Magdi M. Nabi, Ding-Li Yu

Abstract:

Control of a semi-batch polymerization reactor using an adaptive radial basis function (RBF) neural network method is investigated in this paper. A neural network inverse model is used to estimate the valve position of the reactor; this method can identify the controlled system with the RBF neural network identifier. The weights of the adaptive PID controller are timely adjusted based on the identification of the plant and self-learning capability of RBFNN. A PID controller is used in the feedback control to regulate the actual temperature by compensating the neural network inverse model output. Simulation results show that the proposed control has strong adaptability, robustness and satisfactory control performance and the nonlinear system is achieved.

Keywords: Chylla-Haase polymerization reactor, RBF neural networks, feed-forward and feedback control.

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Authors: Richard Joseph, Nerey Mvungi

Abstract:

An electric power system includes a generating, a transmission, a distribution, and consumers subsystems. An electrical power network in Tanzania keeps growing larger by the day and become more complex so that, most utilities have long wished for real-time monitoring and remote control of electrical power system elements such as substations, intelligent devices, power lines, capacitor banks, feeder switches, fault analyzers and other physical facilities. In this paper, the concept of automation of management of power systems from generation level to end user levels was determined by using Power System Simulator for Engineering (PSS/E) version 30.3.2.

Keywords: Automation, Distribution subsystem, Generating subsystem, PSS/E, TANESCO, Transmission subsystem.

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Authors: Mohamed El Aroussi, Mohammed El Hassouni, Sanaa Ghouzali, Mohammed Rziza, Driss Aboutajdine

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In this paper the problem of face recognition under variable illumination conditions is considered. Most of the works in the literature exhibit good performance under strictly controlled acquisition conditions, but the performance drastically drop when changes in pose and illumination occur, so that recently number of approaches have been proposed to deal with such variability. The aim of this work is to introduce an efficient local appearance feature extraction method based steerable pyramid (SP) for face recognition. Local information is extracted from SP sub-bands using LBP(Local binary Pattern). The underlying statistics allow us to reduce the required amount of data to be stored. The experiments carried out on different face databases confirm the effectiveness of the proposed approach.

Keywords: Face recognition (FR), Steerable pyramid (SP), localBinary Pattern (LBP).

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Authors: Maziar Sadeghi, Amir Moradi

Abstract:

This paper proposes a robot able to climb Columns. This robot is not dependent on the diameter and material of the columns. Some climbing robots have been designed up to now but Koala robot was designed and fabricated for climbing columns exclusively. Simple kinematics of climbing in the nature inspired us to design this robot. We used two linear mechanisms to grip the column. The gripper consists of a DC motor and a power screw mechanism with a linear bushing as a guide. This mechanism provides enough force to grip the column. In addition we needed an actuator for climbing the column; hence, two pneumatic jacks were used. All the mechanical parts were designed according to the exerted forces and operational condition. The prototype can be simply installed and controlled on the column by an inexperienced operator. This robot is intended for inspection and surveillance of pipes in oil industries and power poles in electric industries.

Keywords: Robot, Column-climber, Gripping mechanism, Koala.

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Authors: Osamah A. Alsayegh

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Kuwait-s electric power system is vertically integrated organization owned and operated by the government. For more than five decades, the government of Kuwait has provided relatively reliable electric services to consumers with subsidized electric service fees. Given the country-s rapid socio-economical development and consequently the increase of electricity demand, a question that inflicts itself: Is it necessary to reform the power system to face the fast growing demand? This paper recommends that the government should consider the private sector as a partner in operating the power system. Therefore, power system restructuring is needed to allow such partnership. There are challenges that prevent such restructuring. Abstract recommendations toward resolving these challenges are proposed.

Keywords: Deregulation, electricity market, ISO, private sector.

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Authors: JongKuk Kim, HernSoo Hahn, Uei-Joong Yoo, MyungJin Bae

Abstract:

In this paper, we propose a method of alter duration in frequency domain that control prosody in real time after pitch alteration. If there has a method to alteration duration freely among prosody information, that may used in several fields such as speech impediment person's pronunciation proof reading or language study. The pitch alteration method used control prosody altered by PSOLA synthesis method which is in time domain processing method. However, the duration of pitch alteration speech is changed by the frequency domain. In this paper, we altered the duration with the method of duration alteration by Fast Fourier Transformation in frequency domain. Consequently, the intelligibility of the pitch and duration are controlled has a slight decrease than the case when only pitch is changed, but the proposed algorithm obtained the higher MOS score about naturalness.

Keywords: PSOLA, Pitch Alteration, Duration Control.

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Authors: V. K. Bansal

Abstract:

Geographic Information System (GIS) is a computerbased tool used extensively to solve various engineering problems related to spatial data. In spite of growing popularity of GIS, its complete potential to construction industry has not been realized. In this paper, the summary of up-to-date work on spatial applications of GIS technologies in construction industry is presented. GIS technologies have the potential to solve space related problems of construction industry involving complex visualization, integration of information, route planning, E-commerce, cost estimation, etc. GISbased methodology to handle time and space issues of construction projects scheduling is developed and discussed in this paper.

Keywords: Construction, GIS in construction, Scheduling, Project Management.

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Authors: I. Severin, M. Caramihai, R. El Abdi, M. Poulain, A. Avadanii

Abstract:

In order to assess optical fiber reliability in different environmental and stress conditions series of testing are performed simulating overlapping of chemical and mechanical controlled varying factors. Each series of testing may be compared using statistical processing: i.e. Weibull plots. Due to the numerous data to treat, a software application has appeared useful to interpret selected series of experiments in function of envisaged factors. The current paper presents a software application used in the storage, modelling and interpretation of experimental data gathered from optical fibre testing. The present paper strictly deals with the software part of the project (regarding the modelling, storage and processing of user supplied data).

Keywords: Optical fibres, computer aided analysis, data models, data processing, graphical user interfaces.

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Authors: P. Karimi, A. H. Khedmati Bazkiaei

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The main goal of this study is to test differential neural network as a controller of smart structure and is to enumerate its advantages and disadvantages in comparison with other controllers. In this study, the smart structure has been considered as a Euler Bernoulli cantilever beam and it has been tried that it be under control with the use of vibration neural network resulting from movement. Also, a linear observer has been considered as a reference controller and has been compared its results. The considered vibration charts and the controlled state have been recounted in the final part of this text. The obtained result show that neural observer has better performance in comparison to the implemented linear observer.

Keywords: Smart material, on-line differential artificial neural network, active control, finite element method.

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Authors: Steven R. Hawks

Abstract:

The Master-s of Public Health (MPH) degree is growing in popularity among a number of higher education institutions throughout the world as a distance education graduate program. This paper offers an overview of program design and development strategies that promote successful distance delivery of MPH programs. Design and development challenges are discussed in terms of type of distance delivery, accreditation, student demand, faculty development, user needs, course content, and marketing strategies. The ongoing development of a distance education MPH program at Utah State University will be used to highlight and consider various aspects of this important but challenging process.

Keywords: Public health, course content, distance education, higher education, graduate students.

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Authors: Sharil Tumin, Sylvia Encheva

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Centrally controlled authentication and authorization services can provide enterprise with an increase in security, more flexible access control solutions and an increased users' trust. By using redirections, users of all Web-based applications within an organization are authenticated at a single well known and secure Web site and using secure communication protocol. Users are first authenticated at the central server using their domain wide credentials before being redirected to a particular Web-based application. The central authentication server will then provide others with pertinence authorization related particulars and credentials of the authenticated user to the specific application. The trust between the clients and the server hosts is established by secure session keys exchange. Case- studies are provided to demonstrate the usefulness and flexibility of the proposed solution.

Keywords: Authentication, Authorization, Security, Protected Web-based Applications

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Authors: Mohammad Sadeghi, Behrouz Heidari, Korush Montazeri

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In this article, we synthesize a novel chitosan -based superabsorbent hydrogel via graft copolymerization of mixtures acrylic acid (AA) and N-vinyl pyrollidon onto chitosan backbones. The polymerization reaction was carried out in an aqueous medium and in the presence of ammonium persulfate (APS) as an initiator and N,N'-methylene bisacrylamide (MBA) as a crosslinker.The hydrogel structures were confirmed by FTIR spectroscopy. The swelling behavior of these absorbent polymers was also investigated in various salt solutions. Results indicated that the swelling capacity decreased with an increase in the ionic strength of the swelling medium. Furthermore, the swelling of superabsorbing hydrogels was examined in solutions with pH values ranging between 1.0 and 13.0. It showed a reversible pH-responsive behavior at pHs 2.0 and 8.0. This on-off switching behavior makes the synthesized hydrogels as an excellent candidate for controlled delivery of bioactive agents.

Keywords: chitosan, acrylic acid, N-vinyl pyrollidon, hydrogel, Ibuprofen's drug delivery

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Authors: Urszula Wachowska, Anna Daria Stasiulewicz-Paluch, Katarzyna Kucharska

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A three-year field experiment (2010-2012) was conducted to determine the abundance of epiphytic and endophytic filamentous fungi colonizing the grain of winter wheat cv. Bogatka. Wheat spikes were protected with tebuconazole or chitosan at the watery ripe stage. Untreated plants served as control. Tebuconazole exerted an inhibitory effect primarily on F. culmorum and F. graminearum, and its effectiveness was determined by the pressure from pathogens that infected wheat spikes during the growing season. Chitosan did not suppress the growth of Fusarium species and Alternaria alternata.

Keywords: Winter wheat, tebuconazole, chitosan, Fusarium.

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Authors: Sidshchadhaa Aumted, Shuhei Shiina, Hiroshi Takami

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In this paper, we propose an advanced ILQ control for the buck-converter via two-degrees of freedom servo-system. Our presented strategy is based on Inverse Linear Quadratic (ILQ) servo-system controller without solving Riccati-s equation directly. The optimal controller of the current and voltage control system is designed. The stability and robust control are analyzed. A conscious and persistent effort has been made to improve ILQ control via two-degrees of freedom guarantees the optimal gains on the basis of polynomial pole assignment, which our results of the proposed strategy shows that the advanced ILQ control can be controlled independently the step response and the disturbance response by appending a feed-forward compensator.

Keywords: Optimal voltage control, inverse LQ design method, second order polynomial, two-degrees of freedom.

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Authors: A. Inba Rexy, R. Seyezhai

Abstract:

Through the fast growing technologies, design of power factor correction (PFC) circuit is facing several challenges. In this paper, a two-phase interleaved boost converter with ripple steering technique is proposed. Among the various topologies, Interleaved Boost converter (IBC) is considered as superior due to enriched performance, lower ripple content, compact weight and size. A thorough investigation is presented here for the proposed topology. Simulation study for the IBC has been carried out using MATLAB/SIMULINK. Theoretical analysis and hardware prototype has been performed to validate the results.

Keywords: Interleaved Boost Converter (IBC), Power Factor Correction (PFC), Ripple Steering Technique, Ripple, and Simulation.

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Authors: M. Alauddin, M. M. Hossain, M. N. Uddin, M. E. Haque

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An optimal design of a spur is the first requirement to make it sustainable and function properly. In view of that, a thorough understanding to the hydro- and morpho-dynamics due to spurs is essential. This paper presents a literature review on the effect of spurs to obtain the most recent design criteria. Perpendicular and upstream aligned impermeable spurs have large disturbances to flow and less stability because of strong vortices and associated scour. Downstream aligned spurs minimize scour holes, but there is a chance of strong return current which could be controlled allowing flow through them. A series arrangement of spurs is important to have the desired results with a special care for the first one. Several equations have been presented in the paper for predicting the scour depth. But, they have to be used carefully. Different flow environments developed by spurs are favorable for various aquatic species. However, it is important to maintain almost a stable flow condition providing stable spurs.

Keywords: Bed topography, flow pattern, scour, spur.

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Authors: Elham Farahmand, Fatimah Ibrahim, Samira Hosseini, Ivan Djordjevic, Leo. H. Koole

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Compositions of different molar ratios of polymethylmethacrylate-co-methacrylic acid (PMMA-co-MAA) were synthesized via free-radical polymerization. Polymer coated surfaces have been produced on silicon wafers. Coated samples were analyzed by atomic force microscopy (AFM). The results have shown that the roughness of the surfaces have increased by increasing the molar ratio of monomer methacrylic acid (MAA). This study reveals that the gradual increase in surface roughness is due to the fact that carboxylic functional groups have been generated by MAA segments. Such surfaces can be desirable platforms for fabrication of the biosensors for detection of the viruses and diseases.

Keywords: Polymethylmethacrylate-co-methacrylic acid (PMMA-co-MAA), Polymeric material, Atomic Force Microscopy, roughness, carboxylic functional groups.

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Authors: Mehrdad N. Khajavi, Vahid Abdollahi

Abstract:

The purpose of suspension system in automobiles is to improve the ride comfort and road handling. In this research the ride and handling performance of a specific automobile with passive suspension system is compared to a proposed fuzzy logic semi active suspension system designed for that automobile. The bodysuspension- wheel system is modeled as a two degree of freedom quarter car model. MATLAB/SIMULINK [1] was used for simulation and controller design. The fuzzy logic controller is based on two inputs namely suspension velocity and body velocity. The output of the fuzzy controller is the damping coefficient of the variable damper. The result shows improvement over passive suspension method.

Keywords: Suspension System, Ride Comfort, Fuzzy Logic Controller, Passive and Semi Active System.

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Authors: Debabrata Pradhan, Dong J. Kim, Jong G. Ahn, Seoung W. Lee

Abstract:

Spent petroleum catalyst from Korean petrochemical industry contains trace amount of metals such as Ni, V and Mo. Therefore an attempt was made to recover those trace metal using bioleaching process. Different leaching parameters such as Fe(II) concentration, pulp density, pH, temperature and particle size of spent catalyst particle were studied to evaluate their effects on the leaching efficiency. All the three metal ions like Ni, V and Mo followed dual kinetics, i.e., initial faster followed by slower rate. The percentage of leaching efficiency of Ni and V were higher than Mo. The leaching process followed a diffusion controlled model and the product layer was observed to be impervious due to formation of ammonium jarosite (NH4)Fe3(SO4)2(OH)6. In addition, the lower leaching efficiency of Mo was observed due to a hydrophobic coating of elemental sulfur over Mo matrix in the spent catalyst.

Keywords: Bioleaching, diffusion control, shrinking core, spentpetroleum catalyst.

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Authors: M. Z. Norashikin, M. Z. Ibrahim

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The use of plastic materials in agriculture causes serious hazards to the environment. The introduction of biodegradable materials, which can be disposed directly into the soil can be one possible solution to this problem. In the present research results of experimental tests carried out on biodegradable film fabricated from natural waste (corn husk) are presented. The film was characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), thermal gravimetric analysis (TGA) and atomic force microscope (AFM) observation. The film is shown to be readily degraded within 7-9 months under controlled soil conditions, indicating a high biodegradability rate. The film fabricated was use to produce biodegradable pot (BioPot) for seedlings plantation. The introduction and the expanding use of biodegradable materials represent a really promising alternative for enhancing sustainable and environmentally friendly agricultural activities.

Keywords: Environment, waste, plastic, biodegradable.

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Authors: N. Nandan A. M. Nagaraj, L. Sanjeev Kumar

Abstract:

In the rapidly growing population, the requirement of electrical power is increasing day by day. In order to meet the needs, we need to generate the power using alternate method. In this paper, a presentable approach is developed by analysis and can be implemented by utilizing heat energy, which is generated in numerous ways in some of the rural areas in India. The thermoelectric generator unit will be developed by combing with control circuits and converts, which is used to light the LED lamps. The temperature difference which is available in the kitchens, especially the exhaust pipes/chimneys of wooden fire stoves, where more heat is dissipated into the atmosphere, can be utilized for electrical power generation. Hence, the temperature rise of surroundings atmosphere can be reduced.

Keywords: Thermoelectric generator, LED, converts, temperature.

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Authors: Areej R. Banjar, Abraham G. Campbell

Abstract:

The use of Mixed Reality (MR) in teaching and training is growing popular and can improve students’ ability to perform technical procedures. This paper outlines the creation of an interactive educational MR 3D application that aims to improve the quality of instruction for dentistry students. This application is called ”MR-Implantology” and aims to teach and train dentistry students on single dental implant placement. MR-Implantology uses cone-beam computed tomography (CBCT) images as the source for 3D dental models that dentistry students will be able to freely manipulate within a 3D MR world to aid their learning process.

Keywords: Cone-Beam Computed Tomography, dentistry education, implantology, Mixed Reality, MR.

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Authors: Robert Prucek, Aleš Panáček, Jan Filip, Libor Kvítek, Radek Zbořil

Abstract:

The preparation of Cu nanoparticles (NPs) through the reduction of copper ions by sodium borohydride in the presence of sodium polyacrylate with a molecular weight of 1200 is reported. Cu NPs were synthesized at a concentration of copper salt equal to 2.5, 5, and 10 mM, and at a molar ratio of copper ions and monomeric unit of polyacrylate equal to 1:2. The as-prepared Cu NPs have diameters of about 2.5–3 nm for copper concentrations of 2.5 and 5 mM, and 6 nm for copper concentration of 10 mM. Depending on the copper salt concentration and concentration of additionally added polyacrylate to Cu particle dispersion, primarily formed NPs grow through the process of aggregation and/or coalescence into clusters and/or particles with a diameter between 20–100 nm. The amount of additionally added sodium polyacrylate influences the stability of Cu particles against air oxidation. The catalytic efficiency of the prepared Cu particles for the reduction of 4-nitrophenol is discussed.

Keywords: Copper, nanoparticles, sodium polyacrylate, catalyst, 4-nitrophenol.

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Authors: P. Nammalvar, P. Meganathan

Abstract:

This paper presents a hybrid three phase rectifier for high power factor application. This rectifier is composed by zero voltage transition (ZVT) and zero current transition (ZCT) boost converter with three phase diode bridge rectifier, in parallel with a six pulse three phase pulse width modulation (PWM) controlled rectifier. The proposed topology is capable of high power factor with DC output voltage regulation by providing sinusoidal input. Also, it increases the overall efficiency of the new hybrid rectifier to 94.56% and the total harmonic distortion of the hybrid structure varies from 0% to 16% at nominal output power. This topology was simulated in MATLAB/SIMULINK environment and the output waveforms presented with experimental result.

Keywords: Hybrid Rectifier, Total Harmonic Distortion, Power Quality, Pulse Width Modulation (PWM), Unidirectional Rectifier.

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Authors: D. Karimi, M.J. Nategh

Abstract:

One of the main concerns about parallel mechanisms is the presence of singular points within their workspaces. In singular positions the mechanism gains or loses one or several degrees of freedom. It is impossible to control the mechanism in singular positions. Therefore, these positions have to be avoided. This is a vital need especially in computer controlled machine tools designed and manufactured on the basis of parallel mechanisms. This need has to be taken into consideration when selecting design parameters. A prerequisite to this is a thorough knowledge about the effect of design parameters and constraints on singularity. In this paper, quality condition index was introduced as a criterion for evaluating singularities of different configurations of a hexapod mechanism obtainable by different design parameters. It was illustrated that this method can effectively be employed to obtain the optimum configuration of hexapod mechanism with the aim of avoiding singularity within the workspace. This method was then employed to design the hexapod table of a CNC milling machine.

Keywords: Hexapod, Machine Tool, Singularity, Workspace.

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