Search results for: double trans-obturator technique (TOT)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7707

Search results for: double trans-obturator technique (TOT)

7437 Design, Control and Implementation of 300Wp Single Phase Photovoltaic Micro Inverter for Village Nano Grid Application

Authors: Ramesh P., Aby Joseph

Abstract:

Micro Inverters provide Module Embedded Solution for harvesting energy from small-scale solar photovoltaic (PV) panels. In addition to higher modularity & reliability (25 years of life), the MicroInverter has inherent advantages such as avoidance of long DC cables, eliminates module mismatch losses, minimizes partial shading effect, improves safety and flexibility in installations etc. Due to the above-stated benefits, the renewable energy technology with Solar Photovoltaic (PV) Micro Inverter becomes more widespread in Village Nano Grid application ensuring grid independence for rural communities and areas without access to electricity. While the primary objective of this paper is to discuss the problems related to rural electrification, this concept can also be extended to urban installation with grid connectivity. This work presents a comprehensive analysis of the power circuit design, control methodologies and prototyping of 300Wₚ Single Phase PV Micro Inverter. This paper investigates two different topologies for PV Micro Inverters, based on the first hand on Single Stage Flyback/ Forward PV Micro-Inverter configuration and the other hand on the Double stage configuration including DC-DC converter, H bridge DC-AC Inverter. This work covers Power Decoupling techniques to reduce the input filter capacitor size to buffer double line (100 Hz) ripple energy and eliminates the use of electrolytic capacitors. The propagation of the double line oscillation reflected back to PV module will affect the Maximum Power Point Tracking (MPPT) performance. Also, the grid current will be distorted. To mitigate this issue, an independent MPPT control algorithm is developed in this work to reject the propagation of this double line ripple oscillation to PV side to improve the MPPT performance and grid side to improve current quality. Here, the power hardware topology accepts wide input voltage variation and consists of suitably rated MOSFET switches, Galvanically Isolated gate drivers, high-frequency magnetics and Film capacitors with a long lifespan. The digital controller hardware platform inbuilt with the external peripheral interface is developed using floating point microcontroller TMS320F2806x from Texas Instruments. The firmware governing the operation of the PV Micro Inverter is written in C language and was developed using code composer studio Integrated Development Environment (IDE). In this work, the prototype hardware for the Single Phase Photovoltaic Micro Inverter with Double stage configuration was developed and the comparative analysis between the above mentioned configurations with experimental results will be presented.

Keywords: double line oscillation, micro inverter, MPPT, nano grid, power decoupling

Procedia PDF Downloads 133
7436 The Clustering of Multiple Sclerosis Subgroups through L2 Norm Multifractal Denoising Technique

Authors: Yeliz Karaca, Rana Karabudak

Abstract:

Multifractal Denoising techniques are used in the identification of significant attributes by removing the noise of the dataset. Magnetic resonance (MR) image technique is the most sensitive method so as to identify chronic disorders of the nervous system such as Multiple Sclerosis. MRI and Expanded Disability Status Scale (EDSS) data belonging to 120 individuals who have one of the subgroups of MS (Relapsing Remitting MS (RRMS), Secondary Progressive MS (SPMS), Primary Progressive MS (PPMS)) as well as 19 healthy individuals in the control group have been used in this study. The study is comprised of the following stages: (i) L2 Norm Multifractal Denoising technique, one of the multifractal technique, has been used with the application on the MS data (MRI and EDSS). In this way, the new dataset has been obtained. (ii) The new MS dataset obtained from the MS dataset and L2 Multifractal Denoising technique has been applied to the K-Means and Fuzzy C Means clustering algorithms which are among the unsupervised methods. Thus, the clustering performances have been compared. (iii) In the identification of significant attributes in the MS dataset through the Multifractal denoising (L2 Norm) technique using K-Means and FCM algorithms on the MS subgroups and control group of healthy individuals, excellent performance outcome has been yielded. According to the clustering results based on the MS subgroups obtained in the study, successful clustering results have been obtained in the K-Means and FCM algorithms by applying the L2 norm of multifractal denoising technique for the MS dataset. Clustering performance has been more successful with the MS Dataset (L2_Norm MS Data Set) K-Means and FCM in which significant attributes are obtained by applying L2 Norm Denoising technique.

Keywords: clinical decision support, clustering algorithms, multiple sclerosis, multifractal techniques

Procedia PDF Downloads 168
7435 Observer-Based Control Design for Double Integrators Systems with Long Sampling Periods and Actuator Uncertainty

Authors: Tomas Menard

Abstract:

The design of control-law for engineering systems has been investigated for many decades. While many results are concerned with continuous systems with continuous output, nowadays, many controlled systems have to transmit their output measurements through network, hence making it discrete-time. But it is well known that the sampling of a system whose control-law is based on the continuous output may render the system unstable, especially when this sampling period is long compared to the system dynamics. The control design then has to be adapted in order to cope with this issue. In this paper, we consider systems which can be modeled as double integrator with uncertainty on the input since many mechanical systems can be put under such form. We present a control scheme based on an observer using only discrete time measurement and which provides continuous time estimation of the state, combined with a continuous control law, which stabilized a system with second-order dynamics even in the presence of uncertainty. It is further shown that arbitrarily long sampling periods can be dealt with properly setting the control scheme parameters.

Keywords: dynamical system, control law design, sampled output, observer design

Procedia PDF Downloads 187
7434 Dual-Rail Logic Unit in Double Pass Transistor Logic

Authors: Hamdi Belgacem, Fradi Aymen

Abstract:

In this paper we present a low power, low cost differential logic unit (LU). The proposed LU receives dual-rail inputs and generates dual-rail outputs. The proposed circuit can be used in Arithmetic and Logic Units (ALU) of processor. It can be also dedicated for self-checking applications based on dual duplication code. Four logic functions as well as their inverses are implemented within a single Logic Unit. The hardware overhead for the implementation of the proposed LU is lower than the hardware overhead required for standard LU implemented with standard CMOS logic style. This new implementation is attractive as fewer transistors are required to implement important logic functions. The proposed differential logic unit can perform 8 Boolean logical operations by using only 16 transistors. Spice simulations using a 32 nm technology was utilized to evaluate the performance of the proposed circuit and to prove its acceptable electrical behaviour.

Keywords: differential logic unit, double pass transistor logic, low power CMOS design, low cost CMOS design

Procedia PDF Downloads 452
7433 Doubled Haploid Production in Wheat Using Imperata cylindrica Mediated Chromosome Elimination Technique

Authors: Madhu Patial, Dharam Pal, Jagdish Kumar, H. K. Chaudhary

Abstract:

Doubled haploid breeding serves as a useful technique in wheat improvement by providing instant and complete homozygosity. Of the various techniques employed for haploid production chromosome elimination has a large scale practical application in wheat improvement. Barclay (1975) initiated the technique in wheat by crossing wheat variety Chinese spring with Hordeum bulbosum, but due to presence of the dominant crossability inhibitor genes Kr7 and Kr2 in many wheat varieties, the technique was however genotypic specific. The discovery of wheat X maize system of haploid production being genotype non-specific is quite successful but still maize needs to be grown in greenhouse to coincide flowering with wheat crop. Recently, wheat X Imperate cylindrica has been identified as a new chromosome mediated DH approach for efficient haploid induction. An experiment to use this technique in wheat was set up by crossing six F1s and two three way F1s with Imperata cylindrica. The data was recorded for the three component traits of haploid induction viz., seed formation, embryo formation and regeneration frequency. Variation among wheat F1s was observed and higher frequency for all the traits were recorded in cross HD 2997/2*FL-8/DONSK-POLL and KLE/BER/2*FL-8/DONSK-POLL.

Keywords: wheat, haploid, imperata cylindrica, chromosome elimination technique

Procedia PDF Downloads 424
7432 Patterns Obtained by Using Knitting Technique in Textile Crafts

Authors: Özlem Erzurumlu, Nazan Oskay, Ece Melek

Abstract:

Knitting which is one of the textile manufacturing techniques is manufactured by using the system of single yarn. Knitting wares consisting of loops structurally have flexible structures. Knitting can be shaped and given volume easily due to increasing or decreasing the number of loops, being manufactured in circular form and its flexible structure. While the knitting wares are basically being manufactured to meet the requirements, it takes its place in the art field overflowing outside of industrial production later. Textile artist ensures his ideas to convert into artistic product by using textiles and non-textiles with aesthetic concerns and creative impulses. When textile crafts are observed at the present time we see that knitting technique has an extensive area of use such as sculpture, panel, installation art and performing art. It is examined how the knitting technique is used in textile crafts observing patterns obtained by this technique in textile crafts in this study.

Keywords: art, textile, knitting art, textile crafts

Procedia PDF Downloads 707
7431 Oral Betahistine Versus Intravenous Diazepam in Acute Peripheral Vertigo: A Randomized, Double-Blind Controlled Trial

Authors: Saeed Abbasi, Davood Farsi, Soudabeh Shafiee Ardestani, Neda Valizadeh

Abstract:

Objectives: Peripheral vertigo is a common complaint of patients who are visited in emergency departments. In our study, we wanted to evaluate the effect of betahistine as an oral drug vs. intravenous diazepam for the treatment of acute peripheral vertigo. We also wanted to see the possibility of substitution of parenteral drug with an oral one with fewer side effects. Materials and Methods: In this randomized, double-blind study, 101 patients were enrolled in the study. The patients were divided in two groups in a double-blind randomized manner. Group A took oral placebo and 10 mg of intravenous diazepam. Group B received 8mg of oral betahistine and intravenous placebo. Patients’ symptoms and signs (Vertigo severity, Nausea, Vomiting, Nistagmus and Gate) were evaluated after 0, 2, 4, 6 hours by emergency physicians and data were collected by a questionnaire. Results: In both groups, there was significant improvement in vertigo (betahistine group P=0.02 and Diazepam group P=0.03). Analysis showed more improvement in vertigo severity after 4 hours of treatment in betahistine group comparing to diazepam group (P=0.02). Nausea and vomiting were significantly lower in patients receiving diazepam after 2 and 6 hours (P=0.02 & P=0.03).No statistically significant differences were found between the groups in nistagmus, equilibrium & vertigo duration. Conclusion: The results of this randomized trial showed that both drugs had acceptable therapeutic effects in peripheral vertigo, although betahistine was significantly more efficacious after 4 hours of drug intake. As for higher nausea and vomiting in betahistine group, physician should consider these side effects before drug prescription.

Keywords: acute peripheral vertigo, betahistine, diazepam, emergency department

Procedia PDF Downloads 389
7430 Anti-Reflective Nanostructured TiO2/SiO2 Multilayer Coatings

Authors: Najme lari, Shahrokh Ahangarani, Ali Shanaghi

Abstract:

Multilayer structure of thin films by the sol–gel process attracts great attention for antireflection applications. In this paper, antireflective nanometric multilayer SiO2-TiO2 films are formed on both sides of the glass substrates by combining the sol–gel method and the dip-coating technique. SiO2 and TiO2 sols were prepared using tetraethylorthosilicate (TEOS) and tetrabutylorthotitanate (TBOT) as precursors and also nitric acid as catalyst. Prepared coatings were investigated by Field-emission scanning electron microscope (FE-SEM), Fourier-transformed infrared spectrophotometer (FT-IR) and UV–visible spectrophotometer. After evaluation, all of SiO2 top layer coatings showed excellent antireflection in the wavelength range of 400-800 nm where the transmittance of glass substrate is significantly lower. By increasing the number of double TiO2-SiO2 layers, the transmission of the coated glass increases due to applied multilayer coating properties. 6-layer sol–gel TiO2-SiO2 shows the highest visible transmittance about 99.25% at the band of 550-650 nm.

Keywords: thin films, optical properties, sol-gel, multilayer

Procedia PDF Downloads 422
7429 Effect of Different Local Anesthetic Agents on Physiological Parameters and Vital Signs during Extraction in Children

Authors: Rasha F. Sharaf

Abstract:

Administration of local anesthesia for a child is considered a painful procedure, which affects his vital signs, physiological parameters, and his further attitude in the dental clinic. During the extraction of mandibular molars, the nerve block technique is the most commonly used for the administration of local anesthesia; however, this technique requires deep penetration of the needle, which causes pain and discomfort for the child. Therefore, the inferior alveolar nerve block technique can be substituted with an infiltration technique which is not painful if a potent anesthetic solutions will be used. In the current study, the effect of Articaine 4% will be compared to Mepivacaine 2%, and their influence on the vital signs of the child, as well as their ability to control pain during extraction, will be assessed.

Keywords: anesthesia, articaine, pain control, extraction

Procedia PDF Downloads 122
7428 Preliminary Study of Standardization and Validation of Micronuclei Technique to Assess the DNA Damages Cause for the X-Rays

Authors: L. J. Díaz, M. A. Hernández, A. K. Molina, A. Bermúdez, C. Crane, V. M. Pabón

Abstract:

One of the most important biological indicators that show the exposure to the radiation is the micronuclei (MN). This technique is using to determinate the radiation effects in blood cultures as a biological control and a complement to the physics dosimetry. In Colombia the necessity to apply this analysis has emerged due to the current biological indicator most used is the chromosomal aberrations (CA), that is why it is essential the MN technique’s standardization and validation to have enough tools to improve the radioprotection topic in the country. Besides, this technique will be applied on the construction of a dose-response curve, that allow measure an approximately dose to irradiated people according to MN frequency found. Inside the steps that carried out to accomplish the standardization and validation is the statistic analysis from the lectures of “in vitro” peripheral blood cultures with different analysts, also it was determinate the best culture medium and conditions for the MN can be detected easily.

Keywords: micronuclei, radioprotection, standardization, validation

Procedia PDF Downloads 493
7427 Sol-Gel SiO2-TiO2 Multilayer Coatings for Anti-Reflective Applications

Authors: Najme Lari, Shahrokh Ahangarani, Ali Shanaghi

Abstract:

Multilayer structure of thin films by the sol–gel process attracts great attention for antireflection applications. In this paper, antireflective nanometric multilayer SiO2-TiO2 films are formed on both sides of the glass substrates by combining the sol–gel method and the dip-coating technique. SiO2 and TiO2 sols were prepared using tetraethylorthosilicate (TEOS) and tetrabutylorthotitanate (TBOT) as precursors and nitric acid as catalyst. Prepared coatings were investigated by Field-emission scanning electron microscope (FE-SEM), Fourier-transformed infrared spectrophotometer (FT-IR) and UV–visible spectrophotometer. After evaluation, all of SiO2 top layer coatings showed excellent antireflection in the wavelength range of 400-800 nm where the transmittance of glass substrate is significantly lower. By increasing the number of double TiO2-SiO2 layers, the transmission of the coated glass increases due to applied multilayer coating properties. 6-layer sol–gel TiO2-SiO2 shows the highest visible transmittance about 99.25% at the band of 550-650 nm.

Keywords: thin films, optical properties, sol-gel, multilayer

Procedia PDF Downloads 403
7426 Comparison of Conventional Control and Robust Control on Double-Pipe Heat Exchanger

Authors: Hanan Rizk

Abstract:

A heat exchanger is a device used to mix liquids having different temperatures. In this case, the temperature control becomes a critical objective. This research work presents the temperature control of the double-pipe heat exchanger (multi-input multi-output (MIMO) system), which is modeled as first-order coupled hyperbolic partial differential equations (PDEs), using conventional and advanced control techniques and develops appropriate robust control strategy to meet stability requirements and performance objectives. We designed a PID controller and H-infinity controller for a heat exchanger (HE) system. Frequency characteristics of sensitivity functions and open-loop and closed-loop time responses are simulated using MATLAB software, and the stability of the system is analyzed using Kalman's test. The simulation results have demonstrated that the H-infinity controller is more efficient than PID in terms of robustness and performance.

Keywords: heat exchanger, multi-input multi-output system, MATLAB simulation, partial differential equations, PID controller, robust control

Procedia PDF Downloads 220
7425 Physicochemical Characterization of Low Sulfonated Polyether Ether Ketone/ Layered Double Hydroxide/Sepiolite Hybrid to Improve the Performance of Sulfonated Poly Ether Ether Ketone Composite Membranes for Proton Exchange Membrane Fuel Cells

Authors: Zakaria Ahmed, Khaled Charradi, Sherif M. A. S. Keshk, Radhouane Chtourou

Abstract:

Sulfonated poly ether ether ketone (SPEEK) with a low sulfonation degree was blended using nanofiller Layered Double Hydroxide (LDH, Mg2AlCl) /sepiolite nanostructured material as additive to use as an electrolyte membrane for fuel cell application. Characterization assessments, i.e., mechanical stability, thermal gravimetric analysis, ion exchange capability, swelling properties, water uptake capacities, electrochemical impedance spectroscopy analysis, and Fourier transform infrared spectroscopy (FTIR) of the composite membranes were conducted. The presence of LDH/sepiolite nanoarchitecture material within SPEEK was found to have the highest water retention and proton conductivity value at high temperature rather than LDH/SPEEK and pristine SPEEK membranes.

Keywords: SPEEK, sepiolite clay, LDH clay, proton exchange membrane

Procedia PDF Downloads 123
7424 Interfacing Photovoltaic Systems to the Utility Grid: A Comparative Simulation Study to Mitigate the Impact of Unbalanced Voltage Dips

Authors: Badr M. Alshammari, A. Rabeh, A. K. Mohamed

Abstract:

This paper presents the modeling and the control of a grid-connected photovoltaic system (PVS). Firstly, the MPPT control of the PVS and its associated DC/DC converter has been analyzed in order to extract the maximum of available power. Secondly, the control system of the grid side converter (GSC) which is a three-phase voltage source inverter (VSI) has been presented. A special attention has been paid to the control algorithms of the GSC converter during grid voltages imbalances. Especially, three different control objectives are to achieve; the mitigation of the grid imbalance adverse effects, at the point of common coupling (PCC), on the injected currents, the elimination of double frequency oscillations in active power flow, and the elimination of double frequency oscillations in reactive power flow. Simulation results of two control strategies have been performed via MATLAB software in order to demonstrate the particularities of each control strategy according to power quality standards.

Keywords: renewable energies, photovoltaic systems, dc link, voltage source inverter, space vector SVPWM, unbalanced voltage dips, symmetrical components

Procedia PDF Downloads 377
7423 A Novel Parametric Chaos-Based Switching System PCSS for Image Encryption

Authors: Mohamed Salah Azzaz, Camel Tanougast, Tarek Hadjem

Abstract:

In this paper, a new low-cost image encryption technique is proposed and analyzed. The developed chaos-based key generator provides complex behavior and can change it automatically via a random-like switching rule. The designed encryption scheme is called PCSS (Parametric Chaos-based Switching System). The performances of this technique were evaluated in terms of data security and privacy. Simulation results have shown the effectiveness of this technique, and it can thereafter, ready for a hardware implementation.

Keywords: chaos, encryption, security, image

Procedia PDF Downloads 475
7422 Analytical Modeling of Drain Current for DNA Biomolecule Detection in Double-Gate Tunnel Field-Effect Transistor Biosensor

Authors: Ashwani Kumar

Abstract:

Abstract- This study presents an analytical modeling approach for analyzing the drain current behavior in Tunnel Field-Effect Transistor (TFET) biosensors used for the detection of DNA biomolecules. The proposed model focuses on elucidating the relationship between the drain current and the presence of DNA biomolecules, taking into account the impact of various device parameters and biomolecule characteristics. Through comprehensive analysis, the model offers insights into the underlying mechanisms governing the sensing performance of TFET biosensors, aiding in the optimization of device design and operation. A non-local tunneling model is incorporated with other essential models to accurately trace the simulation and modeled data. An experimental validation of the model is provided, demonstrating its efficacy in accurately predicting the drain current response to DNA biomolecule detection. The sensitivity attained from the analytical model is compared and contrasted with the ongoing research work in this area.

Keywords: biosensor, double-gate TFET, DNA detection, drain current modeling, sensitivity

Procedia PDF Downloads 57
7421 Assess and Improve Building Energy Efficiency– a Case Study on the Office of Research and Graduate Studies at Qatar University

Authors: Mohamed Youssef

Abstract:

The proliferation of energy consumption in the built environment has made energy efficiency and savings strategies a priority objective for energy policies in most countries. Qatar is a clear example, where it has initiated several programs and institutions to mitigate the overuse of electricity consumption and control the energy load of the building by following global standards and spreading awareness campaigns. A Case study on the Office of Research and Graduate Studies at Qatar University has been investigated in this paper. The paper studied the rating load of existing buildings before and after retrofitting by using Carrier’s Hourly Analysis Program (HAP). The performance of the building has increased especially after using the LED light system instead of fluorescent light with a low payback period. GINAN paint and green roof have shown a considerable contribution to the reduction of electrical load in the building. In comparison, the double HR window had the least effect on the reduction of electricity consumption.

Keywords: energy conservation in Qatar, HAP, LED light, GINAN paint, green roof, double HR window

Procedia PDF Downloads 172
7420 The Existence of a Sciatic Artery in Congenital Lower Limb Deformities

Authors: Waseem Al Talalwah, Shorok Al Dorazi, Roger Soames

Abstract:

Persistent sciatic artery is a rare anatomical vascular variation resulting from a lack of regression of the embryonic dorsal axial artery. The axial artery is the main artery supplying the lower limb during development in the first trimester. The current research includes 206 sciatic artery cases in 171 patients between 1864 and 2012. It aims to identify the risk factor of sciatic artery aneurysm in congenital limb anomalies. Sciatic artery aneurysm was diagnosed incidentally in amniotic band syndrome (ABS) existing with no congenital anomaly in 0.7% or with double knee in 0.7%, with the tibia in 0.7% and with hemihypertrophy or soft tissue hypertrophy in 1.4%. Therefore, the current study indicates a relationship the same gene responsible for the congenital limb deformities may be responsible for non-regression of the sciatic artery. Furthermore, pediatricians should refer cases of congenital limb anomalies for vascular evaluation prior to corrective surgical intervention.

Keywords: amniotic band syndrome, congenital limb deformities, double knee, sciatic artery, sciatic artery aneurysm , soft tissue hypertrophy

Procedia PDF Downloads 376
7419 The Logistics Equation and Fractal Dimension in Escalators Operations

Authors: Ali Albadri

Abstract:

The logistics equation has never been used or studied in scientific fields outside the field of ecology. It has never been used to understand the behavior of a dynamic system of mechanical machines, like an escalator. We have studied the compatibility of the logistic map against real measurements from an escalator. This study has proven that there is good compatibility between the logistics equation and the experimental measurements. It has discovered the potential of a relationship between the fractal dimension and the non-linearity parameter, R, in the logistics equation. The fractal dimension increases as the R parameter (non-linear parameter) increases. It implies that the fractal dimension increases as the phase of the life span of the machine move from the steady/stable phase to the periodic double phase to a chaotic phase. The fractal dimension and the parameter R can be used as a tool to verify and check the health of machines. We have come up with a theory that there are three areas of behaviors, which they can be classified during the life span of a machine, a steady/stable stage, a periodic double stage, and a chaotic stage. The level of attention to the machine differs depending on the stage that the machine is in. The rate of faults in a machine increases as the machine moves through these three stages. During the double period and the chaotic stages, the number of faults starts to increase and become less predictable. The rate of predictability improves as our monitoring of the changes in the fractal dimension and the parameter R improves. The principles and foundations of our theory in this work have and will have a profound impact on the design of systems, on the way of operation of systems, and on the maintenance schedules of the systems. The systems can be mechanical, electrical, or electronic. The discussed methodology in this paper will give businesses the chance to be more careful at the design stage and planning for maintenance to control costs. The findings in this paper can be implied and used to correlate the three stages of a mechanical system to more in-depth mechanical parameters like wear and fatigue life.

Keywords: logistcs map, bifurcation map, fractal dimension, logistics equation

Procedia PDF Downloads 108
7418 Investigation of the Composition and Structure of Tar by Lignite Pyrolysis Using Thermogravimetry, Gas Chromatography and Mass Spectrum Coupled Instrument System

Authors: Li Feng, Cheng Zhang, Chuanzhou Yuang

Abstract:

Understanding the macromolecular structure of low-rank coal is very important for its gasification and liquefaction. The pyrolysis is one of the methods of analyzing the macromolecular structure of coal. The gaseous products decomposed directly by the raw lignite at 500 °C and indirectly by tar products from raw lignite pyrolysis at 500 °C were investigated and compared by thermogravimetry, gas chromatography and mass spectrum coupled instrument system (TG/GC/MS) in this paper. The results show that 52 kinds of products were found from the raw lignite and 70 kinds of products from the tar. The pyrolysis products directly from the lignite appear more monocyclic aromatic hydrocarbons and less substituent groups or branch chain, compared with the products from the tar. There is less linear chain and double bonds structure in the tar, which can be speculated that linear chain and double bonds structure took part in the generation of condensed rings and other reactions. There are more kinds of phenol and furan in the tar, which indicate that these products may be generated from the secondary reaction. The formation process of phenol, phenol naphthalene, naphthene and furan are discussed.

Keywords: composition and structure, lignite, pyrolysis of coal, tar, TG/GC/MS

Procedia PDF Downloads 141
7417 Fatty Acid Structure and Composition Effects of Biodiesel on Its Oxidative Stability

Authors: Gelu Varghese, Khizer Saeed

Abstract:

Biodiesel is as a mixture of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats. Recent studies in the literature suggest that end property of biodiesel such as its oxidative stability (OS) is highly influenced by the structure and composition of its alkyl esters than by environmental conditions. The structure and composition of these long chain fatty acid components have been also associated with trends in Cetane number, heat of combustion, cold flow properties viscosity, and lubricity. In the present work, detailed investigation has been carried out to decouple and correlate the fatty acid structure indices of biodiesel such as degree of unsaturation, chain length, double bond orientation, and composition with its oxidative stability. Measurements were taken using the EN14214 established Rancimat oxidative stability test method (EN141120). Firstly, effects of the degree of unsaturation, chain length and bond orientation were tested for the pure fatty acids to establish their oxidative stability. Results for pure Fatty acid show that Saturated FAs are more stable than unsaturated ones to oxidation; superior oxidative stability can be achieved by blending biodiesel fuels with relatively high in saturated fatty acid contents. A lower oxidative stability is noticed when a greater quantity of double bonds is present in the methyl ester. A strong inverse relationship with the number of double bonds and the Rancimat IP values can be identified. Trans isomer Methyl elaidate shows superior stability to oxidation than its cis isomer methyl oleate (7.2 vs. 2.3). Secondly, the effects of the variation in the composition of the biodiesel were investigated and established. Finally, biodiesels with varying structure and composition were investigated and correlated.

Keywords: biodiesel, fame, oxidative stability, fatty acid structure, acid composition

Procedia PDF Downloads 286
7416 Improved Processing Speed for Text Watermarking Algorithm in Color Images

Authors: Hamza A. Al-Sewadi, Akram N. A. Aldakari

Abstract:

Copyright protection and ownership proof of digital multimedia are achieved nowadays by digital watermarking techniques. A text watermarking algorithm for protecting the property rights and ownership judgment of color images is proposed in this paper. Embedding is achieved by inserting texts elements randomly into the color image as noise. The YIQ image processing model is found to be faster than other image processing methods, and hence, it is adopted for the embedding process. An optional choice of encrypting the text watermark before embedding is also suggested (in case required by some applications), where, the text can is encrypted using any enciphering technique adding more difficulty to hackers. Experiments resulted in embedding speed improvement of more than double the speed of other considered systems (such as least significant bit method, and separate color code methods), and a fairly acceptable level of peak signal to noise ratio (PSNR) with low mean square error values for watermarking purposes.

Keywords: steganography, watermarking, time complexity measurements, private keys

Procedia PDF Downloads 143
7415 Microstructure and Mechanical Properties of Low Alloy Steel with Double Austenitizing Tempering Heat Treatment

Authors: Jae-Ho Jang, Jung-Soo Kim, Byung-Jun Kim, Dae-Geun Nam, Uoo-Chang Jung, Yoon-Suk Choi

Abstract:

Low alloy steels are widely used for pressure vessels, spent fuel storage, and steam generators required to withstand the internal pressure and prevent unexpected failure in nuclear power plants, which these may suffer embrittlement by high levels of radiation and heat for a long period. Therefore, it is important to improve mechanical properties of low alloy steels for the integrity of structure materials at an early stage of fabrication. Recently, it showed that a double austenitizing and tempering (DTA) process resulted in a significant improvement of strength and toughness by refinement of prior austenite grains. In this study, it was investigated that the mechanism of improving mechanical properties according to the change of microstructure by the second fully austenitizing temperature of the DAT process for low alloy steel required the structural integrity. Compared to conventional single austenitizing and tempering (SAT) process, the tensile elongation properties have improved about 5%, DBTTs have obtained result in reduction of about -65℃, and grain size has decreased by about 50% in the DAT process conditions. Grain refinement has crack propagation interference effect due to an increase of the grain boundaries and amount of energy absorption at low temperatures. The higher first austenitizing temperature in the DAT process, the more increase the spheroidized carbides and strengthening the effect of fine precipitates in the ferrite grain. The area ratio of the dimple in the transition area has increased by proportion to the effect of spheroidized carbides. This may the primary mechanisms that can improve low-temperature toughness and elongation while maintaining a similar hardness and strength.

Keywords: double austenitizing, Ductile Brittle transition temperature, grain refinement, heat treatment, low alloy steel, low-temperature toughness

Procedia PDF Downloads 510
7414 Solutions of Fuzzy Transportation Problem Using Best Candidates Method and Different Ranking Techniques

Authors: M. S. Annie Christi

Abstract:

Transportation Problem (TP) is based on supply and demand of commodities transported from one source to the different destinations. Usual methods for finding solution of TPs are North-West Corner Rule, Least Cost Method Vogel’s Approximation Method etc. The transportation costs tend to vary at each time. We can use fuzzy numbers which would give solution according to this situation. In this study the Best Candidate Method (BCM) is applied. For ranking Centroid Ranking Technique (CRT) and Robust Ranking Technique have been adopted to transform the fuzzy TP and the above methods are applied to EDWARDS Vacuum Company, Crawley, in West Sussex in the United Kingdom. A Comparative study is also given. We see that the transportation cost can be minimized by the application of CRT under BCM.

Keywords: best candidate method, centroid ranking technique, fuzzy transportation problem, robust ranking technique, transportation problem

Procedia PDF Downloads 294
7413 Sensitivity, Specificity and Efficiency Real-Time PCR Using SYBR Green Method to Determine Porcine and Bovine DNA Using Specific Primer Cytochrome B Gene

Authors: Ahlam Inayatullah Badrul Munir, M. Husaini A. Rahman, Mohd Sukri Hassan

Abstract:

Real-time PCR is a molecular biology technique that is currently being widely used for halal services to differentiating between porcine and bovine DNA. The useful of technique become very important for student or workers (who works in the laboratory) to learn how the technique could be run smoothly without fail. Same concept with conventional PCR, real-time PCR also needed DNA template, primer, enzyme polymerase, dNTP, and buffer. The difference is in real-time PCR, have additional component namely fluorescent dye. The most common use of fluorescent dye in real-time PCR is SYBR green. The purpose of this study was to find out how sensitive, specific and efficient real-time PCR technique was combined with SYBR green method and specific primers of CYT b. The results showed that real-time PCR technique using SYBR Green, capable of detecting porcine and bovine DNA concentrations up to 0.0001 µl/ng. The level of efficiency for both types of DNA was 91% (90-110). Not only that in specific primer CYT b bovine primer could detect only bovine DNA, and porcine primer could detect only porcine primer. So, from the study could be concluded that real-time PCR technique that was combined with specific primer CYT b and SYBR green method, was sensitive, specific and efficient to detect porcine and bovine DNA.

Keywords: sensitivity, specificity, efficiency, real-time PCR, SYBR green, Cytochrome b, porcine DNA, bovine DNA

Procedia PDF Downloads 315
7412 Machine Learning Predictive Models for Hydroponic Systems: A Case Study Nutrient Film Technique and Deep Flow Technique

Authors: Kritiyaporn Kunsook

Abstract:

Machine learning algorithms (MLAs) such us artificial neural networks (ANNs), decision tree, support vector machines (SVMs), Naïve Bayes, and ensemble classifier by voting are powerful data driven methods that are relatively less widely used in the mapping of technique of system, and thus have not been comparatively evaluated together thoroughly in this field. The performances of a series of MLAs, ANNs, decision tree, SVMs, Naïve Bayes, and ensemble classifier by voting in technique of hydroponic systems prospectively modeling are compared based on the accuracy of each model. Classification of hydroponic systems only covers the test samples from vegetables grown with Nutrient film technique (NFT) and Deep flow technique (DFT). The feature, which are the characteristics of vegetables compose harvesting height width, temperature, require light and color. The results indicate that the classification performance of the ANNs is 98%, decision tree is 98%, SVMs is 97.33%, Naïve Bayes is 96.67%, and ensemble classifier by voting is 98.96% algorithm respectively.

Keywords: artificial neural networks, decision tree, support vector machines, naïve Bayes, ensemble classifier by voting

Procedia PDF Downloads 372
7411 The Transport of Radical Species to Single and Double Strand Breaks in the Liver’s DNA Molecule by a Hybrid Method of Type Monte Carlo - Diffusion Equation

Authors: H. Oudira, A. Saifi

Abstract:

The therapeutic utility of certain Auger emitters such as iodine-125 depends on their position within the cell nucleus . Or diagnostically, and to maintain as low as possible cell damage, it is preferable to have radionuclide localized outside the cell or at least the core. One solution to this problem is to consider markers capable of conveying anticancer drugs to the tumor site regardless of their location within the human body. The objective of this study is to simulate the impact of a complex such as bleomycin on single and double strand breaks in the DNA molecule. Indeed, this simulation consists of the following transactions: - Construction of BLM -Fe- DNA complex. - Simulation of the electron’s transport from the metastable state excitation of Fe 57 by the Monte Carlo method. - Treatment of chemical reactions in the considered environment by the diffusion equation. For physical, physico-chemical and finally chemical steps, the geometry of the complex is considered as a sphere of 50 nm centered on the binding site , and the mathematical method used is called step by step based on Monte Carlo codes.

Keywords: concentration, yield, radical species, bleomycin, excitation, DNA

Procedia PDF Downloads 457
7410 Rounding Technique's Application in Schnorr Signature Algorithm: Known Partially Most Significant Bits of Nonce

Authors: Wenjie Qin, Kewei Lv

Abstract:

In 1996, Boneh and Venkatesan proposed the Hidden Number Problem (HNP) and proved the most significant bits (MSB) of computational Diffie-Hellman key exchange scheme and related schemes are unpredictable bits. They also gave a method which is a lattice rounding technique to solve HNP in non-uniform model. In this paper, we put forward a new concept that is Schnorr-MSB-HNP. We also reduce the problem of solving Schnorr signature private key with a few consecutive most significant bits of random nonce (used at each signature generation) to Schnorr-MSB-HNP, then we use the rounding technique to solve the Schnorr-MSB-HNP. We have come to the conclusion that if there is a ‘miraculous box’ which inputs the random nonce and outputs 2loglogq (q is a prime number) most significant bits of nonce, the signature private key will be obtained by choosing 2logq signature messages randomly. Thus we get an attack on the Schnorr signature private key.

Keywords: rounding technique, most significant bits, Schnorr signature algorithm, nonce, Schnorr-MSB-HNP

Procedia PDF Downloads 233
7409 Electrochemiluminescent Detection of DNA Damage Induced by Tetrachloro-1,4- Benzoquinone Using DNA Sensor

Authors: Tian-Fang Kang, Xue Sun

Abstract:

DNA damage induced by tetrachloro-1,4-benzoquinone (TCBQ), a reactive metabolite of pentachloro-phenol (PCP), was investigated using a glassy carbon electrode (GCE) modified with calf thymus double-stranded DNA (ds-DNA) in this work. DNA modified films were constructed by layer-by-layer adsorption of polycationic poly(diallyldimethyl- ammonium chloride) (PDDA) and negatively charged ds-DNA on the surface of a glassy carbon electrode. The DNA intercalator [Ru(bpy)2(dppz)]2+ (bpy=2, 2′-bipyridine, dppz0dipyrido [3, 2-a: 2′,3′-c] phenazine) was chosen as an electrochemical probe to detect DNA damage. After the sensor was incubated in 0.1 M pH 7.3 phosphate buffer solution (PBS) for 30min, the intact PDDA/DNA film produced a sensitive electrochemiluminescent (ECL) signal. However, after the sensor was incubated in 100 μM TCBQ or a mixed solution of 100 μM TCBQ and 2 mM H2O2, ECL signal decreased significantly. During the incubation of DNA in TCBQ or TCBQ-H2O2 solution, the double-helix of DNA was damaged, which resulted in the decrease of Ru-dppz bound to DNA. Additionally, the results were verified independently by fluorescence experiments. This paper provides a sensitive method to directly screen DNA damage induced by chemicals in the environment.

Keywords: DNA damage, detection, electrochemiluminescence, sensor

Procedia PDF Downloads 410
7408 Epstein, Barr Virus Alters ATM-Dependent DNA Damage Responses in Germinal Centre B-Cells during Early Infection

Authors: Esther N. Maina, Anna Skowronska, Sridhar Chaganti, Malcolm A. Taylor, Paul G. Murray, Tatjana Stankovic

Abstract:

Epstein-Barr virus (EBV) has been implicated in the pathogenesis of human tumours of B-cell origin. The demonstration that a proportion of Hodgkin lymphomas and all Burkitt’s lymphomas harbour EBV suggests that the virus contributes to the development of these malignancies. However, the mechanisms of lymphomagenesis remain largely unknown. To determine whether EBV causes DNA damage and alters DNA damage response in cells of EBV-driven lymphoma origin, Germinal Centre (GC) B cells were infected with EBV and DNA damage responses to gamma ionising radiation (IR) assessed at early time points (12hr – 72hr) after infection and prior to establishment of lymphoblastoid (LCL) cell lines. In the presence of EBV, we observed induction of spontaneous DNA DSBs and downregulation of ATM-dependent phosphorylation in response to IR. This downregulation coincided with reduced ability of infected cells to repair IR-induced DNA double-strand breaks, as measured by the kinetics of gamma H2AX, a marker of double-strand breaks, and by the tail moment of the comet assay. Furthermore, we found that alteration of DNA damage responses coincided with the expression of LMP-1 protein. The presence of the EBV virus did not affect the localization of the ATM-dependent DNA repair proteins to sites of damage but instead lead to an increased expression of PP5, a phosphatase that regulates ATM function. The impact of the virus on DNA repair was most prominent 24h after infection, suggesting that this time point is crucial for the viral establishment in B cells. Our results suggest that during an early infection EBV virus dampens crucial cellular responses to DNA double-strand breaks which facilitate successful viral infection, but at the same time might provide the mechanism for tumor development.

Keywords: EBV, ATM, DNA damage, germinal center cells

Procedia PDF Downloads 349