Search results for: impedance control
1004 A Single Phase ZVT-ZCT Power Factor Correction Boost Converter
Authors: Yakup Sahin, Naim Suleyman Ting, Ismail Aksoy
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In this paper, a single phase soft switched Zero Voltage Transition and Zero Current Transition (ZVT-ZCT) Power Factor Correction (PFC) boost converter is proposed. In the proposed PFC converter, the main switch turns on with ZVT and turns off with ZCT without any additional voltage or current stresses. Auxiliary switch turns on and off with zero current switching (ZCS). Also, the main diode turns on with zero voltage switching (ZVS) and turns off with ZCS. The proposed converter has features like low cost, simple control and structure. The output current and voltage are controlled by the proposed PFC converter in wide line and load range. The theoretical analysis of converter is clarified and the operating steps are given in detail. The simulation results of converter are obtained for 500 W and 100 kHz. It is observed that the semiconductor devices operate with soft switching (SS) perfectly. So, the switching power losses are minimum. Also, the proposed converter has 0.99 power factor with sinusoidal current shape.Keywords: Power factor correction, zero-voltage transition, zero-current transition, soft switching.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19971003 Entropy Generation Analyze Due to the Steady Natural Convection of Newtonian Fluid in a Square Enclosure
Authors: T. T. Naas, Y. Lasbet, C. Kezrane
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The thermal control in many systems is widely accomplished applying mixed convection process due to its low cost, reliability and easy maintenance. Typical applications include the aircraft electronic equipment, rotating-disc heat exchangers, turbo machinery, and nuclear reactors, etc. Natural convection in an inclined square enclosure heated via wall heater has been studied numerically. Finite volume method is used for solving momentum and energy equations in the form of stream function–vorticity. The right and left walls are kept at a constant temperature, while the other parts are adiabatic. The range of the inclination angle covers a whole revolution. The method is validated for a vertical cavity. A general power law dependence of the Nusselt number with respect to the Rayleigh number with the coefficient and exponent as functions of the inclination angle is presented. For a fixed Rayleigh number, the inclination angle increases or decreases is found.
Keywords: Inclined enclosure, natural convection in enclosure, Nusselt number.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22201002 Effect of Capsule Storage on Viability of Lactobacillus bulgaricus and Streptococcus thermophilus in Yogurt Powder
Authors: Kanchana Sitlaothaworn
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Yogurt capsule was made by mixing 14% w/v of reconstitution of skim milk with 2% FOS. The mixture was fermented by commercial yogurt starter comprising Lactobacillus bulgaricus and Streptococcus thermophilus. These yogurts were made as yogurt powder by freeze-dried. Yogurt powder was put into capsule then stored for 28 days at 4oc. 8ml of commercial yogurt was found to be the most suitable inoculum size in yogurt production. After freeze-dried, the viability of L. bulgaricus and S. thermophilus reduced from 109 to 107 cfu/g. The precence of sucrose cannot help to protect cell from ice crystal formation in freeze-dried process, high (20%) sucrose reduced L. bulgaricus and S. thermophilus growth during fermentation of yogurt. The addition of FOS had reduced slowly the viability of both L. bulgaricus and S. thermophilus similar to control (without FOS) during 28 days of capsule storage. The viable cell exhibited satisfactory viability level in capsule storage (6.7x106cfu/g) during 21 days at 4oC.Keywords: Yogurt capsule, Lactobacillus bulgaricus, Streptococcus thermophilus, freeze-drying, sucrose.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13811001 Sensitivity Analysis for Determining Priority of Factors Controlling SOC Content in Semiarid Condition of West of Iran
Authors: Y. Parvizi, M. Gorji, M.H. Mahdian, M. Omid
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Soil organic carbon (SOC) plays a key role in soil fertility, hydrology, contaminants control and acts as a sink or source of terrestrial carbon content that can affect the concentration of atmospheric CO2. SOC supports the sustainability and quality of ecosystems, especially in semi-arid region. This study was conducted to determine relative importance of 13 different exploratory climatic, soil and geometric factors on the SOC contents in one of the semiarid watershed zones in Iran. Two methods canonical discriminate analysis (CDA) and feed-forward back propagation neural networks were used to predict SOC. Stepwise regression and sensitivity analysis were performed to identify relative importance of exploratory variables. Results from sensitivity analysis showed that 7-2-1 neural networks and 5 inputs in CDA models output have highest predictive ability that explains %70 and %65 of SOC variability. Since neural network models outperformed CDA model, it should be preferred for estimating SOC.Keywords: Soil organic carbon, modeling, neural networks, CDA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14201000 Weigh-in-Motion Data Analysis Software for Developing Traffic Data for Mechanistic Empirical Pavement Design
Authors: M. A. Hasan, M. R. Islam, R. A. Tarefder
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Currently, there are few user friendly Weigh-in- Motion (WIM) data analysis softwares available which can produce traffic input data for the recently developed AASHTOWare pavement Mechanistic-Empirical (ME) design software. However, these softwares have only rudimentary Quality Control (QC) processes. Therefore, they cannot properly deal with erroneous WIM data. As the pavement performance is highly sensible to the quality of WIM data, it is highly recommended to use more refined QC process on raw WIM data to get a good result. This study develops a userfriendly software, which can produce traffic input for the ME design software. This software takes the raw data (Class and Weight data) collected from the WIM station and processes it with a sophisticated QC procedure. Traffic data such as traffic volume, traffic distribution, axle load spectra, etc. can be obtained from this software; which can directly be used in the ME design software.Keywords: Weigh-in-motion, software, axle load spectra, traffic distribution, AASHTOWare.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1885999 The Effect of Goat Milk Fractions Supplementation on Serum IgE Response and Leukocytes Count in Dinitrochlorobenzene Sensitized Rat
Authors: Nurliyani, E. Harmayani, MHNE. Soesatyo
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In Indonesia, goat milk is often consumed and believed as anti-allergy. The objective of this research was to study the effect of goat milk and their fractions (casein and whey) supplementation on total serum IgE concentrations and leukocytes count in rat sensitized with contact allergen dinitrochlorobenzene (DNCB). Female Wistar rats 6-8 weeks old were divided into four groups: 1) whey, 2) casein, 3) whole milk supplementation and 4) phosphate-buffered saline/PBS (control). The results showed that supplementation of goat milk on rats did not affects on total serum IgE concentrations and number of leukocytes. After sensitized with DNCB, the monocyte percentage in rats was higher (P<0.01) than before. In conclusion, goat milk or their fractions supplementation unable to decrease the total serum IgE concentrations and also had no effect on leukocytes count. However, 1% DNCB could increase the number of monocytes, but could not induce the IgE response.Keywords: Dinitrochlorobenzene, Goat Milk Fractions, IgE, Leukocytes.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1575998 Laser Doppler Flowmetry in Diagnostics of Vascular Lesions in Lower Extremities
Authors: Petr V. Vasilev, Eduard V. Volkov, Alexej N. Godok, Alexej A, Grischschuk, Vitalij A. Rybalchenko
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Laser Doppler flowmetry is a modern method of noninvasive microcirculation investigation. The aim of our study was to use this method in the examination of patients with secondary lymphedema of the lower extremities and obliterating atherosclerosis of lower extremities. In the analysis of the amplitude-frequency spectrum of secondary lymphedema patients we have identified remarkable changes. To describe the changes we used a special amplitude rate. In both of patients groups this rate was significally (p<0.05) different with the control group. So the marker phenomena of the amplitude-frequency spectrum of the LDF signal were identified. It is suggested that there is a limfodynamics contribution to the formation of the output signal of laser Doppler flowmetry. These data have fundamental meaning and are interesting for practical medicine, as they give an opportunity to further developments for the use of laser Doppler flowmetry in the diagnostics and monitoring the effectiveness of the treatment.Keywords: laser Doppler flowmetry, secondary lymphedema of the lower extremities, obliterating atherosclerosis, non-invasive diagnostics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1717997 The Effectiveness of ICT-Assisted PBL on College-Level Nano Knowledge and Learning Skills
Authors: Ya-Ting Carolyn Yang, Ping-Han Cheng, Shi-Hui Gilbert Chang, Terry Yuan-Fang Chen, Chih-Chieh Li
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Nanotechnology is widely applied in various areas so professionals in the related fields have to know more than nano knowledge. In the study, we focus on adopting ICT-assisted PBL in college general education to foster professionals who possess multiple abilities. The research adopted a pretest and posttest quasi-experimental design. The control group received traditional instruction, and the experimental group received ICT-assisted PBL instruction. Descriptive statistics will be used to describe the means, standard deviations, and adjusted means for the tests between the two groups. Next, analysis of covariance (ANCOVA) will be used to compare the final results of the two research groups after 6 weeks of instruction. Statistics gathered in the end of the research can be used to make contrasts. Therefore, we will see how different teaching strategies can improve students’ understanding about nanotechnology and learning skills.
Keywords: Nanotechnology, science education, project-based learning, information and communication technology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2063996 Evaluation of South African Plants with Acaricide Activity against Ticks
Authors: G. Fouché, J. N. Eloff, K. Wellington
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Acaricides are commonly used to control ticks but are toxic, harmful to the environment and too expensive to resource-limited farmers. Traditionally, many communities in South Africa rely on a wide range of indigenous practices to keep their livestock healthy. One of these health care practices includes the use of medicinal plants and this offers an alternative to conventional medicine. An investigation was conducted at the CSIR in South Africa, and selected indigenous plants used in communities were scientifically evaluated for the management of ticks in animals. 17 plants were selected from 239 plants used traditionally in South Africa. Two different organic extracts were prepared from the 17 samples, resulting in 34 plant samples. These were tested for efficacy against two tick species, namely Rhipicephalus microplus and Rhipicephalus turanicus. The plant extracts were also screened against Vero cells and most were found to have low cytotoxicity. This study has shown that there is potential for the development of botanicals as natural acaricides against ticks that are non-toxic and environmentally benign.
Keywords: Rhipicephalus microplus, Rhipicephalus turanicus, ticks, plant extracts, South Africa.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1201995 Separation Characteristics of Dissolved Gases from Water Concurrently Variable Mixed with Exhalations for the Hollow Fiber Membrane
Authors: Pil Woo Heo
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Water contains dissolved oxygen that a fish needs to breathe. It is important to increase the amounts of separation of dissolved oxygen from water for diverse applications using the separation system. In this paper, a separation system of dissolved gases from water concurrently variable mixed with the exhalations using a compressor is proposed. This system takes use of exhalations to increase the amounts of separation of dissolved oxygen from water. A compressor with variable off-time and on-time is used to control the exhalations mixed with inlet water. Exhalations contain some portion of carbon dioxide, oxygen, and nitrogen. Separation of dissolved gases containing dissolved oxygen is enhanced by using exhalations. The amounts of separation and the compositions of carbon dioxide and oxygen are measured. Higher amounts of separation can make the size of the separation device smaller, and then, application areas are diversified.
Keywords: Concurrently, variable mixed, exhalations, separation, hollow fiber.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1097994 Power Flow Control with UPFC in Power Transmission System
Authors: Samina Elyas Mubeen, R. K. Nema, Gayatri Agnihotri
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In this paper the performance of unified power flow controller is investigated in controlling the flow of po wer over the transmission line. Voltage sources model is utilized to study the behaviour of the UPFC in regulating the active, reactive power and voltage profile. This model is incorporated in Newton Raphson algorithm for load flow studies. Simultaneous method is employed in which equations of UPFC and the power balance equations of network are combined in to one set of non-linear algebraic equations. It is solved according to the Newton raphson algorithm. Case studies are carried on standard 5 bus network. Simulation is done in Matlab. The result of network with and without using UPFC are compared in terms of active and reactive power flows in the line and active and reactive power flows at the bus to analyze the performance of UPFC.Keywords: Newton-Raphson algorithm, Load flow, Unified power flow controller, Voltage source model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4272993 Digital Homeostasis: Tangible Computing as a Multi-Sensory Installation
Authors: Andrea Macruz
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This paper explores computation as a process for design by examining how computers can become more than an operative strategy in a designer's toolkit. It documents this, building upon concepts of neuroscience and Antonio Damasio's Homeostasis Theory, which is the control of bodily states through feedback intended to keep conditions favorable for life. To do this, it follows a methodology through algorithmic drawing and discusses the outcomes of three multi-sensory design installations, which culminated from a course in an academic setting. It explains both the studio process that took place to create the installations and the computational process that was developed, related to the fields of algorithmic design and tangible computing. It discusses how designers can use computational range to achieve homeostasis related to sensory data in a multi-sensory installation. The outcomes show clearly how people and computers interact with different sensory modalities and affordances. They propose using computers as meta-physical stabilizers rather than tools.
Keywords: Antonio Damasio, emotional feedback, algorithmic drawing, homeostasis, multi-sensory installation, neuroscience.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 334992 Localizing Acoustic Touch Impacts using Zip-stuffing in Complex k-space Domain
Authors: R. Bremananth, Andy W. H. Khong, A. Chitra
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Visualizing sound and noise often help us to determine an appropriate control over the source localization. Near-field acoustic holography (NAH) is a powerful tool for the ill-posed problem. However, in practice, due to the small finite aperture size, the discrete Fourier transform, FFT based NAH couldn-t predict the activeregion- of-interest (AROI) over the edges of the plane. Theoretically few approaches were proposed for solving finite aperture problem. However most of these methods are not quite compatible for the practical implementation, especially near the edge of the source. In this paper, a zip-stuffing extrapolation approach has suggested with 2D Kaiser window. It is operated on wavenumber complex space to localize the predicted sources. We numerically form a practice environment with touch impact databases to test the localization of sound source. It is observed that zip-stuffing aperture extrapolation and 2D window with evanescent components provide more accuracy especially in the small aperture and its derivatives.Keywords: Acoustic source localization, Near-field acoustic holography (NAH), FFT, Extrapolation, k-space wavenumber errors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1634991 Cloning and Over Expression of an Aspergillus niger XP Phytase Gene (phyA) in Pichia pastoris
Authors: Ngo Thanh Xuan, Mai Thi Hang, Vu Nguyen Thanh
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A. niger XP isolated from Vietnam produces very low amount of acidic phytase with optimal pH at 2.5 and 5.5. The phytase production of this strain was successfully improved through gene cloning and expression. A 1.4 - kb DNA fragment containing the coding region of the phyA gene was amplified by PCR and inserted into the expression vector pPICZαA with a signal peptide α- factor, under the control of AOX1 promoter. The recombined plasmid was transformed into the host strain P. pastoris KM71H and X33 by electroporation. Both host strains could efficiently express and secret phytase. The multicopy strains were screened for over expression of phytase. All the selected multicopy strains of P. pastoris X33 were examined for phytase activity, the maximum phytase yield of 1329 IU/ml was obtained after 4 days of incubation in medium BMM. The recombinant protein with MW of 97.4 KW showed to be the only one protein secreted in the culture broth. Multicopy transformant P. pastoris X33 supposed to be potential candidate for producing the commercial preparation of phytase.
Keywords: Aspergillus niger XP, cloning, over expression, Pichia pastoris, phyA , phytase.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2195990 Mutational Analysis of CTLA4 Gene in Pakistani SLE Patients
Authors: N. Hussain, G. Jaffery, A.N. Sabri, S. Hasnain
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The main aim is to perform mutational analysis of CTLA4 gene Exon 1 in SLE patients. A total of 61 SLE patients fulfilling “American College of Rheumatology (ACR) criteria" and 61 controls were enrolled in this study. The region of CTLA4 gene exon 1 was amplified by using Step-down PCR technique. Extracted DNA of band 354 bp was sequenced to analyze mutations in the exon-1 of CTLA-4 gene. Further, protein sequences were identified from nucleotide sequences of CTLA4 Exon 1 by using Expasy software and through Blast P software it was found that CTLA4 protein sequences of Pakistani SLE patients were similar to that of Chinese SLE population. No variations were found after patients sequences were compared with that of the control sequence. Furthermore it was found that CTLA4 protein sequences of Pakistani SLE patients were similar to that of Chinese SLE population. Thus CTLA4 gene may not be responsible for an autoimmune disease SLE.
Keywords: American College of Rheumatology criteria, autoimmune disease, Cytotoxic T Lymphocyte Antigen-4, Polymerase Chain Reaction, Systemic Lupus Erythematosus
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1512989 Numerical Simulation of Investment Casting of Gold Jewelry: Experiments and Validations
Authors: Marco Actis Grande, Somlak Wannarumon
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This paper proposes the numerical simulation of the investment casting of gold jewelry. It aims to study the behavior of fluid flow during mould filling and solidification and to optimize the process parameters, which lead to predict and control casting defects such as gas porosity and shrinkage porosity. A finite difference method, computer simulation software FLOW-3D was used to simulate the jewelry casting process. The simplified model was designed for both numerical simulation and real casting production. A set of sensor acquisitions were allocated on the different positions of the wax tree of the model to detect filling times, while a set of thermocouples were allocated to detect the temperature during casting and cooling. Those detected data were applied to validate the results of the numerical simulation to the results of the real casting. The resulting comparisons signify that the numerical simulation can be used as an effective tool in investment-casting-process optimization and casting-defect prediction.Keywords: Computer fluid dynamic, Investment casting, Jewelry, Mould filling, Simulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2723988 Investigation of Various PWM Techniques for Shunt Active Filter
Authors: J. Chelladurai, G. Saravana Ilango, C. Nagamani, S. Senthil Kumar
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Pulse width modulation (PWM) techniques have been the subject of intensive research for different industrial and power sector applications. A large variety of methods, different in concept and performance, have been newly developed and described. This paper analyzes the comparative merits of Sinusoidal Pulse Width Modulation (SPWM) and Space Vector Pulse Width Modulation (SVPWM) techniques and the suitability of these techniques in a Shunt Active Filter (SAF). The objective is to select the scheme that offers effective utilization of DC bus voltage and also harmonic reduction at the input side. The effectiveness of the PWM techniques is tested in the SAF configuration with a non linear load. The performance of the SAF with the SPWM and (SVPWM) techniques are compared with respect to the THD in source current. The study reveals that in the context of closed loop SAF control with the SVPWM technique there is only a minor improvement in THD. The utilization of the DC bus with SVPWM is also not significant compared to that with SPWM because of the non sinusoidal modulating signal from the controller in SAF configuration.Keywords: Voltage source inverter, Shunt active filter, SPWM, SVPWM, Matlab/SIMULINK.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2777987 QCM-D Study on Relationship of PEG Coated Stainless Steel Surfaces to Protein Resistance
Authors: Norzita Ngadi, John Abrahamson, Conan Fee, Ken Morison
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Nonspecific protein adsorption generally occurs on any solid surfaces and usually has adverse consequences. Adsorption of proteins onto a solid surface is believed to be the initial and controlling step in biofouling. Surfaces modified with end-tethered poly(ethylene glycol) (PEG) have been shown to be protein-resistant to some degree. In this study, the adsorption of β-casein and lysozyme was performed on 6 different types of surfaces where PEG was tethered onto stainless steel by polyethylene imine (PEI) through either OH or NHS end groups. Protein adsorption was also performed on the bare stainless steel surface as a control. The adsorption was conducted at 23 °C and pH 7.2. In situ QCM-D was used to determine PEG adsorption kinetics, plateau PEG chain densities, protein adsorption kinetics and plateau protein adsorbed quantities. PEG grafting density was the highest for a NHS coupled chain, around 0.5 chains / nm2. Interestingly, lysozyme which has smaller size than β-casein, appeared to adsorb much less mass than that of β- casein. Overall, the surface with high PEG grafting density exhibited a good protein rejection.Keywords: QCM-D, PEG, stainless steel, β-casein, lysozyme.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1979986 Soil Compaction in Tropical Organic Farming Systems and Its Impact on Natural Soil-Borne Disease Suppression: Challenges for Management
Authors: Ishak, L., McHenry, M. T., Brown, P. H.
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Organic farming systems still depend on intensive, mechanical soil tillage. Frequent passes by machinery traffic cause substantial soil compaction that threatens soil health. Adopting practices as reduced tillage and organic matter retention on the soil surface are considered effective ways to control soil compaction. In tropical regions, however, the acceleration of soil organic matter decomposition and soil carbon turnover on the topsoil layer is influenced more rapidly by the oscillation process of drying and wetting. It is hypothesized therefore, that rapid reduction in soil organic matter hastens the potential for compaction to occur in organic farming systems. Compaction changes soil physical properties and as a consequence it has been implicated as a causal agent in the inhibition of natural disease suppression in soils. Here we describe relationships between soil management in organic vegetable systems, soil compaction, and declining soil capacity to suppress pathogenic microorganisms.
Keywords: Organic farming systems, soil compaction, soil disease suppression, tropical regions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2144985 Water Quality Assessment Based on Operational Indicator in West Coastal Water of Malaysia
Authors: Seyedeh Belin Tavakoly Sany, H. Rosli, R. Majid, S. Aishah
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In this study, water monitoring was performed from Nov. 2012 to Oct. 2013 to assess water quality and evaluate the spatial and temporal distribution of physicochemical and biological variables in water. Water samples were collected from 10 coastal water stations of West Port. In the case of water-quality assessment, multi-metric indices and operational indicators have been proposed to classify the trophic status at different stations. The trophic level of West Port coastal water ranges from eutrophic to hypertrophic. Chl-a concentration was used to estimate the biological response of phytoplankton biomass and indicated eutrophic conditions in West Port and mesotrophic conditions at the control site. During the study period, no eutrophication events or secondary symptoms occurred, which may be related to hydrodynamic turbulence and water exchange, which prevent the development of eutrophic conditions in the West Port.Keywords: Water quality, multi-metric indices, operational indicator, Malaysia, West Port.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1776984 Bandwidth Estimation Algorithms for the Dynamic Adaptation of Voice Codec
Authors: Davide Pierattoni, Ivan Macor, Pier Luca Montessoro
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In the recent years multimedia traffic and in particular VoIP services are growing dramatically. We present a new algorithm to control the resource utilization and to optimize the voice codec selection during SIP call setup on behalf of the traffic condition estimated on the network path. The most suitable methodologies and the tools that perform realtime evaluation of the available bandwidth on a network path have been integrated with our proposed algorithm: this selects the best codec for a VoIP call in function of the instantaneous available bandwidth on the path. The algorithm does not require any explicit feedback from the network, and this makes it easily deployable over the Internet. We have also performed intensive tests on real network scenarios with a software prototype, verifying the algorithm efficiency with different network topologies and traffic patterns between two SIP PBXs. The promising results obtained during the experimental validation of the algorithm are now the basis for the extension towards a larger set of multimedia services and the integration of our methodology with existing PBX appliances.Keywords: Integrated voice-data communication, computernetwork performance, resource optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1680983 Effect of Fuel Lean Reburning Process on NOx Reduction and CO Emission
Authors: Changyeop Lee, Sewon Kim
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Reburning is a useful technology in reducing nitric oxide through injection of a secondary hydrocarbon fuel. In this paper, an experimental study has been conducted to evaluate the effect of fuel lean reburning on NOx/CO reduction in LNG flame. Experiments were performed in flames stabilized by a co-flow swirl burner, which was mounted at the bottom of the furnace. Tests were conducted using LNG gas as the reburn fuel as well as the main fuel. The effects of reburn fuel fraction and injection manner of the reburn fuel were studied when the fuel lean reburning system was applied. The paper reports data on flue gas emissions and temperature distribution in the furnace for a wide range of experimental conditions. At steady state, temperature distribution and emission formation in the furnace have been measured and compared. This paper makes clear that in order to decrease both NOx and CO concentrations in the exhaust when the pulsated fuel lean reburning system was adapted, it is important that the control of some factors such as frequency and duty ratio. Also it shows the fuel lean reburning is also effective method to reduce NOx as much as reburning.
Keywords: Fuel lean reburn, NOx, CO, LNG flame.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2188982 Robust H∞ Filter Design for Uncertain Fuzzy Descriptor Systems: LMI-Based Design
Authors: Wudhichai Assawinchaichote, Sing Kiong Nguang
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This paper examines the problem of designing a robust H∞ filter for a class of uncertain fuzzy descriptor systems described by a Takagi-Sugeno (TS) fuzzy model. Based on a linear matrix inequality (LMI) approach, LMI-based sufficient conditions for the uncertain nonlinear descriptor systems to have an H∞ performance are derived. To alleviate the ill-conditioning resulting from the interaction of slow and fast dynamic modes, solutions to the problem are given in terms of linear matrix inequalities which are independent of the singular perturbation ε, when ε is sufficiently small. The proposed approach does not involve the separation of states into slow and fast ones and it can be applied not only to standard, but also to nonstandard uncertain nonlinear descriptor systems. A numerical example is provided to illustrate the design developed in this paper.
Keywords: H∞ control, Takagi-Sugeno (TS) fuzzy model, Linear Matrix Inequalities (LMIs), Descriptor systems.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1392981 Feasibility of the Evolutionary Algorithm using Different Behaviours of the Mutation Rate to Design Simple Digital Logic Circuits
Authors: Konstantin Movsovic, Emanuele Stomeo, Tatiana Kalganova
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The evolutionary design of electronic circuits, or evolvable hardware, is a discipline that allows the user to automatically obtain the desired circuit design. The circuit configuration is under the control of evolutionary algorithms. Several researchers have used evolvable hardware to design electrical circuits. Every time that one particular algorithm is selected to carry out the evolution, it is necessary that all its parameters, such as mutation rate, population size, selection mechanisms etc. are tuned in order to achieve the best results during the evolution process. This paper investigates the abilities of evolution strategy to evolve digital logic circuits based on programmable logic array structures when different mutation rates are used. Several mutation rates (fixed and variable) are analyzed and compared with each other to outline the most appropriate choice to be used during the evolution of combinational logic circuits. The experimental results outlined in this paper are important as they could be used by every researcher who might need to use the evolutionary algorithm to design digital logic circuits.Keywords: Evolvable hardware, evolutionary algorithm, digitallogic circuit, mutation rate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1488980 Physical Characteristics of Cookies Enriched with Microencapsulated Cherry Pomace Extract
Authors: Jovana Petrović, Ivana Lončarević, Vesna Tumbas Šaponjac, Biljana Pajin, Danica Zarić
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Pomace, a by-product from fruit processing industry is the potential source of valuable bioactive. Cookies are popular, ready to eat and low price foods; therefore, enrichment of these products is of great importance. In this work, bioactive compounds extracted from cherry pomace, encapsulated in soy and whey proteins, have been incorporated in cookies, replacing 10 (SP10 and WP10) and 15% of wheat flour (SP15 and WP15). Cookie geometry (diameter (D), thickness (T) and spread ratio (D/T)), cookie weight, cookie hardness and cookie surface colour were measured. Sensory characteristics are also examined. The results show that encapsulated cherry pomace bioactives have positively influenced the cookie mass. Diameter, redness (a* value) and cookie hardness increased. Sensory evaluation of cookies, revealed that up to 15% substitution of wheat flour with WP encapsulate produced acceptable cookies similar to the control (100% wheat flour) cookies.Keywords: Cherry pomace, polyphenols, microencapsulation, cookies, physical characteristics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1787979 Identification of Differentially Expressed Gene(DEG) in Atherosclerotic Lesion by Annealing Control Primer (ACP)-Based Genefishing™ PCR
Authors: M. Maimunah, G. A. Froemming, H. Nawawi, M. I. Nafeeza, O. Effat, M. Y. Rosmadi, M. S. Mohamed Saifulaman
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Atherosclerosis was identified as a chronic inflammatory process resulting from interactions between plasma lipoproteins, cellular components (monocyte, macrophages, T lymphocytes, endothelial cells and smooth muscle cells) and the extracellular matrix of the arterial wall. Several types of genes were known to express during formation of atherosclerosis. This study is carried out to identify unknown differentially expressed gene (DEG) in atherogenesis. Rabbit’s aorta tissues were stained by H&E for histomorphology. GeneFishing™ PCR analysis was performed from total RNA extracted from the aorta tissues. The DNA fragment from DEG was cloned, sequenced and validated by Real-time PCR. Histomorphology showed intimal thickening in the aorta. DEG detected from ACP-41 was identified as cathepsin B gene and showed upregulation at week-8 and week-12 of atherogenesis. Therefore, ACP-based GeneFishing™ PCR facilitated identification of cathepsin B gene which was differentially expressed during development of atherosclerosis.
Keywords: Atherosclerosis, GeneFishing™ PCR, cathepsin B gene.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1945978 Effect of Crude oil Intoxication on Antioxidant and Marker Enzymes of Tissue Damage in Liver of Rat
Authors: K. Mahmoud, T. Shalahmetova, Sh. Deraz
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The objective of the present study was to examine the dose-response relationships between antioxidant parameters and liver contaminant levels of Kazakhstan light crude oil (KLCO) in albino rats. The animals were repeatedly exposed, by intraperitoneal injection, to low dosages (0.5–1.5 ml/kg) of KLCO. Rats exposed to these doses levels did not show any apparent symptoms of intoxication. Serum aminotransferases increased significantly (p<0.05) while after 8-d recovered to control level. hepatic superoxide dismutase (SOD) activity significantly increased after 1 and 3-d except with 0.5 ml while with increased exposure time it deceased insignificantly after 5-d and significantly after 8-d. Dose and time-dependent increases were observed in the levels of hepatic glutathione-S-transeferase (GST) and conjugated diene (CD) while malondialdehyde (MDA) was evolved after 8 with the dose of 1.5 ml. the data obtained indicate impaired liver function in the rats intoxicated with KLCO as manifested by elevated liver enzymes.Keywords: Crude oil; superoxide dismutase, glutathione-Stranseferase, malondialdehyde, conjugated diene, aminotransferases.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2164977 Evaluation for Punching Shear Strength of Slab-Column Connections with Ultra High Performance Fiber-Reinforced Concrete Overlay
Authors: H. S. Youm, S. G. Hong
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This paper presents the test results on 5 slab-column connection specimens with Ultra High Performance Fiber-Reinforced Concrete (UHPFRC) overlay including 1 control specimen to investigate retrofitting effect of UHPFRC overlay on the punching shear capacity. The test parameters were the thickness of the UHPFRC overlay and the amount of steel re-bars in it. All specimens failed in punching shear mode with abrupt failure aspect. The test results showed that by adding a thin layer of UHPFRC over the Reinforced Concrete (RC) substrates, considerable increases in global punching shear resistance up to 82% and structural rigidity were achieved. Furthermore, based on the cracking patterns the composite systems appeared to be governed by two failure modes: 1) diagonal shear failure in RC section and 2) debonding failure at the interface.
Keywords: Punching shear strength, retrofit, slab-column connection, UHPFRC, UHPFRC overlay.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 999976 Unsupervised Clustering Methods for Identifying Rare Events in Anomaly Detection
Authors: Witcha Chimphlee, Abdul Hanan Abdullah, Mohd Noor Md Sap, Siriporn Chimphlee, Surat Srinoy
Abstract:
It is important problems to increase the detection rates and reduce false positive rates in Intrusion Detection System (IDS). Although preventative techniques such as access control and authentication attempt to prevent intruders, these can fail, and as a second line of defence, intrusion detection has been introduced. Rare events are events that occur very infrequently, detection of rare events is a common problem in many domains. In this paper we propose an intrusion detection method that combines Rough set and Fuzzy Clustering. Rough set has to decrease the amount of data and get rid of redundancy. Fuzzy c-means clustering allow objects to belong to several clusters simultaneously, with different degrees of membership. Our approach allows us to recognize not only known attacks but also to detect suspicious activity that may be the result of a new, unknown attack. The experimental results on Knowledge Discovery and Data Mining-(KDDCup 1999) Dataset show that the method is efficient and practical for intrusion detection systems.Keywords: Network and security, intrusion detection, fuzzy cmeans, rough set.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2844975 An Exhaustive Review of Die Sinking Electrical Discharge Machining Process and Scope for Future Research
Authors: M. M. Pawade, S. S. Banwait
Abstract:
Electrical Discharge Machine (EDM) is especially used for the manufacturing of 3-D complex geometry and hard material parts that are extremely difficult-to-machine by conventional machining processes. In this paper authors review the research work carried out in the development of die-sinking EDM within the past decades for the improvement of machining characteristics such as Material Removal Rate, Surface Roughness and Tool Wear Ratio. In this review various techniques reported by EDM researchers for improving the machining characteristics have been categorized as process parameters optimization, multi spark technique, powder mixed EDM, servo control system and pulse discriminating. At the end, flexible machine controller is suggested for Die Sinking EDM to enhance the machining characteristics and to achieve high-level automation. Thus, die sinking EDM can be integrated with Computer Integrated Manufacturing environment as a need of agile manufacturing systems.Keywords: Electrical Discharge Machine, Flexible Machine Controller, Material Removal Rate, Tool Wear Ratio.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5285