Search results for: Antioxidant response
906 Research on Static and Dynamic Behavior of New Combination of Aluminum Honeycomb Panel and Rod Single-layer Latticed Shell
Authors: Xu Chen, Zhao Caiqi
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In addition to the advantages of light weight, resistant corrosion and ease of processing, aluminum is also applied to the long-span spatial structures. However, the elastic modulus of aluminum is lower than that of the steel. This paper combines the high performance aluminum honeycomb panel with the aluminum latticed shell, forming a new panel-and-rod composite shell structure. Through comparative analysis between the static and dynamic performance, the conclusion that the structure of composite shell is noticeably superior to the structure combined before.Keywords: Combination of aluminum honeycomb panel and rod latticed shell, dynamic performance, response spectrum analysis, seismic properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1944905 A Servo Control System Using the Loop Shaping Design Procedure
Authors: Naohiro Ban, Hiromitsu Ogawa, Manato Ono, Yoshihisa Ishida
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This paper describes an expanded system for a servo system design by using the Loop Shaping Design Procedure (LSDP). LSDP is one of the H∞ design procedure. By conducting Loop Shaping with a compensator and robust stabilization to satisfy the index function, we get the feedback controller that makes the control system stable. In this paper, we propose an expanded system for a servo system design and apply to the DC motor. The proposed method performs well in the DC motor positioning control. It has no steady-state error in the disturbance response and it has robust stability.Keywords: Loop Shaping Design Procedure (LSDP), servosystem, DC motor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2410904 Using Finite Element Method for Determination of Poles Number in Optimal Design of Linear Motor
Authors: Abdolamir Nekoubin
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One of Effective parameters on the performance of linear induction motors is number of poles which must be selected and optimized to increase power efficiency and motor performance significantly. In this paper a double-sided linear induction motor with different poles number by using MAXWELL3D software is designed and with finite element method is analyzed electromagnetically. Then for dynamic simulation, linear motor by using MATLAB software is simulated. The results show that by adding poles number, system time response is increased and motor after more time reaches to steady state. Also propulsion force of motor is increased.
Keywords: Linear motor, poles number, finite element method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2188903 The External Debt in the Context of Economic Growth: The Sample of Turkey
Authors: Ayşen Edirneligil, Mehmet Mucuk
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In developing countries, one of the most important restrictions about the economic growth is the lack of national savings which are supposed to finance the investments. In order to overcome this restriction and achieve the higher rate of economic growth by increasing the level of output, countries choose the external borrowing. However, there is a dispute in the literature over the correlation between external debt and economic growth. The aim of this study is to examine the effects of external debt on Turkish economic growth by using VAR analysis with the quarterly data over the period of 2002:01-2014:04. In this respect, Johansen Cointegration Test, Impulse- Response Function and Variance Decomposition Tests will be used for analyses. Empirical findings show that there is no cointegration in the long run.Keywords: Economic growth, external debt, time series analysis, Turkish economy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2226902 The Impact of Metacognitive Knowledge and Experience on Top Management Team Diversity and Small to Medium Enterprises Performance
Authors: Jo Rhodes, Peter Lok, Zahra Sadeghinejad
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The aim of this study is to determine the impact of metacognition on top management team members and firm performance based on full team integration. A survey of 1500 small to medium enterprises (SMEs) was initiated and 140 firms were obtained in this study (with response rate of 9%). The result showed that different metacognitive abilities of managers [knowledge and experience] could enhance team decision-making and problem solving, resulting in greater firm performance. This is a significant finding for SMEs because these organisations have small teams with owner leadership and entrepreneurial orientation.
Keywords: Metacognition, behavioural integration, top management team, performance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1290901 Channel Length Modulation Effect on Monolayer Graphene Nanoribbon Field Effect Transistor
Authors: Mehdi Saeidmanesh, Razali Ismail
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Recently, Graphene Nanoribbon Field Effect Transistors (GNR FETs) attract a great deal of attention due to their better performance in comparison with conventional devices. In this paper, channel length Modulation (CLM) effect on the electrical characteristics of GNR FETs is analytically studied and modeled. To this end, the special distribution of the electric potential along the channel and current-voltage characteristic of the device is modeled. The obtained results of analytical model are compared to the experimental data of published works. As a result, it is observable that considering the effect of CLM, the current-voltage response of GNR FET is more realistic.Keywords: Graphene nanoribbon, field effect transistors, short channel effects, channel length modulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1278900 Blind Non-Minimum Phase Channel Identification Using 3rd and 4th Order Cumulants
Authors: S. Safi, A. Zeroual
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In this paper we propose a family of algorithms based on 3rd and 4th order cumulants for blind single-input single-output (SISO) Non-Minimum Phase (NMP) Finite Impulse Response (FIR) channel estimation driven by non-Gaussian signal. The input signal represents the signal used in 10GBASE-T (or IEEE 802.3an-2006) as a Tomlinson-Harashima Precoded (THP) version of random Pulse-Amplitude Modulation with 16 discrete levels (PAM-16). The proposed algorithms are tested using three non-minimum phase channel for different Signal-to-Noise Ratios (SNR) and for different data input length. Numerical simulation results are presented to illustrate the performance of the proposed algorithms.Keywords: Higher Order Cumulants, Channel identification, Ethernet communication.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1448899 Assessment of Collapse Potential of Degrading SDOF Systems
Authors: Muzaffer Borekci, Murat S. Kirçil
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Predicting the collapse potential of a structure during earthquakes is an important issue in earthquake engineering. Many researchers proposed different methods to assess the collapse potential of structures under the effect of strong ground motions. However most of them did not consider degradation and softening effect in hysteretic behavior. In this study, collapse potential of SDOF systems caused by dynamic instability with stiffness and strength degradation has been investigated. An equation was proposed for the estimation of collapse period of SDOF system which is a limit value of period for dynamic instability. If period of the considered SDOF system is shorter than the collapse period then the relevant system exhibits dynamic instability and collapse occurs.
Keywords: Collapse, degradation, dynamic instability, seismic response.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2097898 Synchronization of Oestrus in Goats with Progestogen Sponges and Short Term Combined FGA, PGF2α Protocols
Authors: G. Martemucci, D. Casamassima, A. G. D'Alessandro
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The study aimed to evaluated the reproductive performance response to short term oestrus synchronization during the transition period. One hundred and sixty-five indigenous multiparous non-lactating goats were subdivided into the following six treatment groups for oestrus synchronization: NT control Group (N= 30), Fe-21d, FGA vaginal sponge for 21days+eCG at 19thd; FPe- 11d, FGA 11d + PGF2α and eCG at 9th d; FPe-10d, FGA 10d+ PGF2α and eCG at 8th d; FPe-9d, FGA 9d +PGF2α and eCG at 7thd; PFe-5d, PGF2α at d0 + FGA 5d + eCG at 5thd. The goats were natural mated (1 male/6 females). Fecundity rates (n. births /n. females treated x 100) were statistically higher (P < 0.05) in short term FPe-9d (157.9%), FPe- 11d (115.4%), FPe-10d (111.1%) and PFe-5d (107.7%) groups compared to the NT control Group (66.7%).
Keywords: Goats, oestrus synchronization, short-term protocols.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4461897 An Optical Sensing Film for Fe(III) Determination Based on 1,1′- diethyl 2,2′- cyanine Iodide Immobilized in Nafion Film
Authors: K. Kajsanthia, J. Wittayakun, S. Prayoonpokarach
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An optical chemical sensing film based on immobilizing of 1,1′- diethyl 2,2′-cyanine (pseudocyanine iodide) in nafion film was developed for the determination of Fe(III). The sensing film was homogeneous, transparent, and mechanically stable. Decrease of the absorbance measured at 518 nm was observed when the sensing film was immersed in a solution of Fe(III). The optimum response of the sensing film to Fe(III) was obtained in a solution with pH 4.0. Linear calibration curve over an Fe(III) concentration range of 1-30 ppm with a limit of detection of 0.71 ppm was obtained. Cd(II) is the major interference. The sensing film exhibited good stability for 2 months and high reproducibility. The proposed method was applied for the determination of Fe(III) in water samples with satisfactory results.Keywords: iron(III), _nafion, optical sensing film, pseudocyanine iodide
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1476896 Application Procedure for Optimized Placement of Buckling Restrained Braces in Reinforced Concrete Building Structures
Authors: S. A. Faizi, S. Yoshitomi
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The optimal design procedure of buckling restrained braces (BRBs) in reinforced concrete (RC) building structures can provide the distribution of horizontal stiffness of BRBs at each story, which minimizes story drift response of the structure under the constraint of specified total stiffness of BRBs. In this paper, a simple rule is proposed to convert continuous horizontal stiffness of BRBs into sectional sizes of BRB which are available from standardized section list assuming realistic structural design stage.
Keywords: Buckling restrained brace, building engineering, optimal damper placement, structural engineering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1397895 Factorial Design Analysis for Quality of Video on MANET
Authors: Hyoup-Sang Yoon
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The quality of video transmitted by mobile ad hoc networks (MANETs) can be influenced by several factors, including protocol layers; parameter settings of each protocol. In this paper, we are concerned with understanding the functional relationship between these influential factors and objective video quality in MANETs. We illustrate a systematic statistical design of experiments (DOE) strategy can be used to analyze MANET parameters and performance. Using a 2k factorial design, we quantify the main and interactive effects of 7 factors on a response metric (i.e., mean opinion score (MOS) calculated by PSNR with Evalvid package) we then develop a first-order linear regression model between the influential factors and the performance metric.
Keywords: Evalvid, full factorial design, mobile ad hoc networks, ns-2.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2086894 Maximizing Performance of the Membranes Based on Quaternized Polysulfone/Polyvinil Alcohol for Biomedical Applications: Rheological Investigations
Authors: A. Filimon, R. M. Albu, E. Avram
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The rheological response of blends obtained from quaternized polysulfone and polyvinyl alcohol in N-methyl-2- pyrrolidone as against structural peculiarity of polymers from the blend, composition of polymer mixtures, as well as the types of interactions were investigated. Results show that the variation of polyvinyl alcohol composition in the studied system determines changes of the rheological properties, suggesting that the PVA acts as a plasticizer. Consequently, rheological behavior of complex system, described by the nonlinear flow curve, indicates the impact of polyvinil alcohol content to polysulfone solution, in order to facilitate the subsequently preparation of bioactive membranes.
Keywords: Membranes for biomedical applications, quaternized polysulfone/polyvinyl alcohol composites, rheological properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1846893 Estimation of Train Operation Using an Exponential Smoothing Method
Authors: Taiyo Matsumura, Kuninori Takahashi, Takashi Ono
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The purpose of this research is to improve the convenience of waiting for trains at level crossings and stations and to prevent accidents resulting from forcible entry into level crossings, by providing level crossing users and passengers with information that tells them when the next train will pass through or arrive. For this paper, we proposed methods for estimating operation by means of an average value method, variable response smoothing method, and exponential smoothing method, on the basis of open data, which has low accuracy, but for which performance schedules are distributed in real time. We then examined the accuracy of the estimations. The results showed that the application of an exponential smoothing method is valid.
Keywords: Exponential smoothing method, open data, operation estimation, train schedule.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 714892 Innovation in Business
Authors: Noemy Witt Ferreira, Flávio de São Paulo Filho
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Innovation, technology and knowledge are the trilogy of impact to support the challenges arising from uncertainty. Evidence showed an opportunity to ask how to manage in this environment under constant innovation. In an attempt to get a response from the field of Management Sciences, based in the Contingency Theory, a research was conducted, with phenomenological and descriptive approaches, using the Case Study Method and the usual procedures for this task involving a focus group composed of managers and employees working in the pharmaceutical field. The problem situation was raised; the state of the art was interpreted and dissected the facts. In this tasks were involved four establishments. The result indicates that these focused ventures have been managed by its founder empirically and is experimenting agility described in this work. The expectation of this study is to improve concepts for stakeholders on creativity in business.Keywords: Administration. Innovation. Knowledge, Management Technology
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2031891 On Face Recognition using Gabor Filters
Authors: Al-Amin Bhuiyan, Chang Hong Liu
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Gabor-based face representation has achieved enormous success in face recognition. This paper addresses a novel algorithm for face recognition using neural networks trained by Gabor features. The system is commenced on convolving a face image with a series of Gabor filter coefficients at different scales and orientations. Two novel contributions of this paper are: scaling of rms contrast and introduction of fuzzily skewed filter. The neural network employed for face recognition is based on the multilayer perceptron (MLP) architecture with backpropagation algorithm and incorporates the convolution filter response of Gabor jet. The effectiveness of the algorithm has been justified over a face database with images captured at different illumination conditions.Keywords: Fuzzily skewed filter, Gabor filter, rms contrast, neural network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3101890 Design Charts for Strip Footing on Untreated and Cement Treated Sand Mat over Underlying Natural Soft Clay
Authors: Sharifullah Ahmed, Sarwar Jahan Md. Yasin
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Shallow foundations on unimproved soft natural soils can undergo a high consolidation and secondary settlement. For low and medium rise building projects on such soil condition, pile foundation may not be cost effective. In such cases an alternative to pile foundations may be shallow strip footings placed on a double layered improved soil system soil. The upper layer of this system is untreated or cement treated compacted sand and underlying layer is natural soft clay. This system will reduce the settlement to an allowable limit. The current research has been conducted with the settlement of a rigid plane-strain strip footing of 2.5 m width placed on the surface of a soil consisting of an untreated or cement treated sand layer overlying a bed of homogeneous soft clay. The settlement of the mentioned shallow foundation has been studied considering both cases with the thicknesses of the sand layer are 0.3 to 0.9 times the width of footing. The response of the clay layer is assumed as undrained for plastic loading stages and drained during consolidation stages. The response of the sand layer is drained during all loading stages. FEM analysis was done using PLAXIS 2D Version 8.0. A natural clay deposit of 15 m thickness and 18 m width has been modeled using Hardening Soil Model, Soft Soil Model, Soft Soil Creep Model, and upper improvement layer has been modeled using only Hardening Soil Model. The groundwater level is at the top level of the clay deposit that made the system fully saturated. Parametric study has been conducted to determine the effect of thickness, density, cementation of the sand mat and density, shear strength of the soft clay layer on the settlement of strip foundation under the uniformly distributed vertical load of varying value. A set of the chart has been established for designing shallow strip footing on the sand mat over thick, soft clay deposit through obtaining the particular thickness of sand mat for particular subsoil parameter to ensure no punching shear failure and no settlement beyond allowable level. Design guideline in the form of non-dimensional charts has been developed for footing pressure equivalent to medium-rise residential or commercial building foundation with strip footing on soft inorganic Normally Consolidated (NC) soil of Bangladesh having void ratio from 1.0 to 1.45.
Keywords: Design charts, ground improvement, PLAXIS 2D, primary and secondary settlement, sand Mat, soft clay.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 670889 The Cracks Propagation Monitoring of a Cantilever Beam Using Modal Analysis
Authors: Morteza Raki, Abolghasem Zabihollah, Omid Askari
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Cantilever beam is a simplified sample of a lot of mechanical components used in a wide range of applications, including many industries such as gas turbine blade. Due to the nature of the operating conditions, beams are subject to variety of damages especially crack propagates. Crack propagation may lead to catastrophic failure during operation. Therefore, online detection of crack presence and its propagation is very important and may reduce possible significant cost of the whole system failure. This paper aims to investigate the effect of cracks presence and crack propagation on one end fixed beam`s vibration. A finite element model will be developed for the blade in which the modal response of the structure with and without crack will be studied.Keywords: Blade, crack propagation, health monitoring, modal analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2003888 Modeling and Simulation of PSM DC-DC Buck Converter
Authors: Ramamurthy S, Vanaja Ranjan P
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A DC-to-DC converter for applications involving a source with widely varying voltage conditions with loads requiring constant voltage from full load down to no load is presented. The switching regulator considered is a Buck converter with Pulse Skipping Modulation control whereby pulses applied to the switch are blocked or released on output voltage crossing a predetermined value. Results of the study on the performance of regulator circuit are presented. The regulator regulates over a wide input voltage range with slightly higher ripple content and good transient response. Input current spectrum indicates a good EMI performance with crowding of components at low frequency range.Keywords: DC/DC Converter, Pulse Skipping Modulation, Buckregulator, Modulation Factor, Electromagnetic Interference
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2418887 Angle of Arrival Detection with Fifth Order Phase Operators
Authors: Youssef Khmou, Said Safi
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In this paper, a fifth order propagator operators are proposed for estimating the Angles Of Arrival (AOA) of narrowband electromagnetic waves impinging on antenna array when its number of sensors is larger than the number of radiating sources.
The array response matrix is partitioned into five linearly dependent phases to construct the noise projector using five different propagators from non diagonal blocks of the spectral matrice of the received data; hence, five different estimators are proposed to estimate the angles of the sources. The simulation results proved the performance of the proposed estimators in the presence of white noise comparatively to high resolution eigen based spectra.
Keywords: DOA, narrowband, antenna, propagator, high resolution. Array, operator, angular, spectrum, goniometry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1503886 Integrating Blogging into Peer Assessment on College Students’ English Writing
Authors: Su-Lien Liao
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Most of college students in Taiwan do not have sufficient English proficiency to express themselves in written English. Teachers spent a lot of time correcting the errors in students’ English writing, but the results are not satisfactory. This study aims to use blogs as a teaching and learning tool in written English. Before applying peer assessment, students should be trained to be good reviewers. The teacher starts the course by posting the error analysis of students’ first English composition on blogs as the comment models for students. Then the students will go through the process of drafting, composing, peer response and last revision on blogs. Evaluation questionnaires and interviews will be conducted at the end of the course to see the impact and also students’ perception for the course.
Keywords: Blog, Peer assessment, English writing, Error analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1938885 Evaluation of the Displacement-Based and the Force-Based Adaptive Pushover Methods in Seismic Response Estimation of Irregular Buildings Considering Torsional Effects
Authors: R. Abbasnia, F. Mohajeri Nav, S. Zahedifar, A. Tajik
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Recent years, adaptive pushover methods have been developed for seismic analysis of structures. Herein, the accuracy of the displacement-based adaptive pushover (DAP) method, which is introduced by Antoniou and Pinho [2004], is evaluated for Irregular buildings. The results are compared to the force-based procedure. Both concrete and steel frame structures, asymmetric in plan and elevation are analyzed and also torsional effects are taking into the account. These analyses are performed using both near fault and far fault records. In order to verify the results, the Incremental Dynamic Analysis (IDA) is performed.Keywords: Pushover Analysis, DAP, IDA, Torsion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3097884 Snails and Fish as Pollution Biomarkers in Lake Manzala and Laboratory C: Laboratory Exposed Snails to Chemical Mixtures
Authors: Hanaa M. M. El-Khayat, Hoda Abdel-Hamid, Kadria M. A. Mahmoud, Hanan S. Gaber, Hoda, M. A. Abu Taleb, Hassan E. Flefel
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Snails are considered as suitable diagnostic organisms for heavy metal–contaminated sites. Biomphalaria alexandrina snails are used in this work as pollution bioindicators after exposure to chemical mixtures consisted of heavy metals (HM); zinc (Zn), copper (Cu) and lead (Pb); and persistent organic pollutants; Decabromodiphenyl ether 98% (D) and Aroclor 1254 (A). The impacts of these tested chemicals, individual and mixtures, on liver and kidney functions, antioxidant enzymes, complete blood picture, and tissue histology were studied. Results showed that Cu was proved to be the highly toxic against snails than Zn and Pb where LC50 values were 1.362, 213.198 and 277.396 ppm, respectively. Also, B. alexandrina snails exposed to the mixture of HM (¼ LC5 Cu, Pb and Zn) showed the highest bioaccumulation of Cu and Zn in their whole tissue, the most significant increase in AST, ALT & ALP activities and the highest significant levels of total protein, albumin and globulin. Results showed significant alterations in CAT activity in snail tissue extracts while snail samples exposed to most experimental tests showed significant increase in GST activity. Snail samples that exposed to HM mixtures showed a significant decrease in total hemocytes count while snail samples that exposed to mixtures containing A & D showed a significant increase in total hemocytes and Hyalinocytes. Histopathological alterations in snail samples exposed to individual HM and their mixtures for 4 weeks showed degeneration, edema, hyper trophy and vaculation in head-foot muscle, degeneration and necrotic changes in the digestive gland and accumulation in most tested organs. Also, the hermaphrodite gland showed mature ova with irregular shape and reduction in sperm number. In conclusion, the resulted damage and alterations in B. alexandrina studied parameters can be used as bioindicators to the presence of pollutants in its habitats.Keywords: Biomphalaria, Zn, Cu, Pb, AST, ALT, ALP, total protein albumin, globulin, CAT and Histopathology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1244883 A Visco-elastic Model for High-density Cellulose Insulation Materials
Authors: Jonas Engqvist, Per Hard af Segerstad, Birger Bring, Mathias Wallin
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A macroscopic constitutive equation is developed for a high-density cellulose insulation material with emphasis on the outof- plane stress relaxation behavior. A hypothesis is proposed where the total stress is additively composed by an out-of-plane visco-elastic isotropic contribution and an in-plane elastic orthotropic response. The theory is validated against out-of-plane stress relaxation, compressive experiments and in-plane tensile hysteresis, respectively. For large scale finite element simulations, the presented model provides a balance between simplicity and capturing the materials constitutive behaviour.
Keywords: Cellulose insulation materials, constitutive modelling, material characterisation, pressboard.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2212882 Ultrafast Transistor Laser Containing Graded Index Separate Confinement Heterostructure
Authors: Mohammad Hosseini
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Ultrafast transistor laser investigated here has the graded index separate confinement heterostructure (GRIN-SCH) in its base region. Resonance-free optical frequency response with -3 dB bandwidth of more than 26 GHz has been achieved for a single quantum well transistor laser by using graded index layers of AlξGa1-ξAs (ξ: 0.1→0) in the left side of quantum well and AlξGa1-ξAs (ξ: 0.05→0) in the right side of quantum well. All required parameters, including quantum well and base transit time, optical confinement factor and spontaneous recombination lifetime, have been calculated using a self-consistent charge control model.
Keywords: Transistor laser, ultrafast, GRIN-SCH, -3db optical bandwidth, AlξGa1-ξAs.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 174881 Sparsity-Aware and Noise-Robust Subband Adaptive Filter
Authors: Young-Seok Choi
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This paper presents a subband adaptive filter (SAF) for a system identification where an impulse response is sparse and disturbed with an impulsive noise. Benefiting from the uses of l1-norm optimization and l0-norm penalty of the weight vector in the cost function, the proposed l0-norm sign SAF (l0-SSAF) achieves both robustness against impulsive noise and much improved convergence behavior than the classical adaptive filters. Simulation results in the system identification scenario confirm that the proposed l0-norm SSAF is not only more robust but also faster and more accurate than its counterparts in the sparse system identification in the presence of impulsive noise.Keywords: Subband adaptive filter, l0-norm, sparse system, robustness, impulsive interference.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1790880 Investigating Prostaglandin E2 and Intracellular Oxidative Stress Levels in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages upon Treatment with Strobilanthes crispus
Authors: Anna Pick Kiong Ling, Jia May Chin, Rhun Yian Koh, Ying Pei Wong
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Background: Uncontrolled inflammation may cause serious inflammatory diseases if left untreated. Non-steroidal anti-inflammatory drug (NSAIDs) is commonly used to inhibit pro-inflammatory enzymes, thus, reduce inflammation. However, long term administration of NSAIDs leads to various complications. Medicinal plants are getting more attention as it is believed to be more compatible with human body. One of them is a flavonoid-containing medicinal plants, Strobilanthes crispus which has been traditionally claimed to possess anti-inflammatory and antioxidant activities. Nevertheless, its anti-inflammatory activities are yet to be scientifically documented. Objectives: This study aimed to examine the anti-inflammatory activity of S. crispus by investigating its effects on intracellular oxidative stress and prostaglandin E2 (PGE2) levels. Materials and Methods: In this study, the Maximum Non-toxic Dose (MNTD) of methanol extract of both leaves and stems of S. crispus was first determined using 3-(4,5-dimethylthiazolyl-2)-2,5-diphenytetrazolium Bromide (MTT) assay. The effects of S. crispus extracts at MNTD and half MNTD (½MNTD) on intracellular ROS as well as PGE2 levels in 1.0 µg/mL LPS-stimulated RAW 264.7 macrophages were then be measured using DCFH-DA and a competitive enzyme immunoassay kit, respectively. Results: The MNTD of leaf extract was determined as 700µg/mL while for stem was as low as 1.4µg/mL. When LPS-stimulated RAW 264.7 macrophages were subjected to the MNTD of S. crispus leaf extract, both intracellular ROS and PGE2 levels were significantly reduced. In contrast, stem extract at both MNTD and ½MNTD did not significantly reduce the PGE2 level, but significantly increased the intracellular ROS level. Conclusion: The methanol leaf extract of S. crispus may possess anti-inflammatory properties as it is able to significantly reduce the intracellular ROS and PGE2 levels of LPS-stimulated cells. Nevertheless, further studies such as investigating the interleukin, nitric oxide and cytokine tumor necrosis factor-α (TNFα) levels has to be conducted to further confirm the anti-inflammatory properties of S. crispus.Keywords: Anti-inflammatory, natural products, prostaglandin E2, reactive oxygen species.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1513879 Symbolic Analysis of Large Circuits Using Discrete Wavelet Transform
Authors: Ali Al-Ataby , Fawzi Al-Naima
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Symbolic Circuit Analysis (SCA) is a technique used to generate the symbolic expression of a network. It has become a well-established technique in circuit analysis and design. The symbolic expression of networks offers excellent way to perform frequency response analysis, sensitivity computation, stability measurements, performance optimization, and fault diagnosis. Many approaches have been proposed in the area of SCA offering different features and capabilities. Numerical Interpolation methods are very common in this context, especially by using the Fast Fourier Transform (FFT). The aim of this paper is to present a method for SCA that depends on the use of Wavelet Transform (WT) as a mathematical tool to generate the symbolic expression for large circuits with minimizing the analysis time by reducing the number of computations.Keywords: Numerical Interpolation, Sparse Matrices, SymbolicAnalysis, Wavelet Transform.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1551878 Computation of Induction Current in a Set of Dendrites
Authors: Sudhakar Tripathi, R. B. Mishra
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In this paper, the cable model of dendrites have been considered. The dendrites are cylindrical cables of various segments having variable length and reducing radius from start point at synapse and end points. For a particular event signal being received by a neuron in response only some dendrite are active at a particular instance. Initial current signals with different current flows in dendrite are assumed. Due to overlapping and coupling of active dendrite, they induce currents in the dendrite segments of each other at a particular instance. But how these currents are induced in the various segments of active dendrites due to coupling between these dendrites, It is not presented in the literature. Here the paper presents a model for induced currents in active dendrite segments due to mutual coupling at the starting instance of an activity in dendrite. The model is as discussed further.Keywords: Currents, dendrites, induction, simulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1515877 Finite Difference Method of the Seismic Analysis of Earth Dam
Authors: Alaoua Bouaicha, Fahim Kahlouche, Abdelhamid Benouali
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Many embankment dams have suffered failures during earthquakes due to the increase of pore water pressure under seismic loading. After analyzing of the behavior of embankment dams under severe earthquakes, major advances have been attained in the understanding of the seismic action on dams. The present study concerns numerical analysis of the seismic response of earth dams. The procedure uses a nonlinear stress-strain relation incorporated into the code FLAC2D based on the finite difference method. This analysis provides the variation of the pore water pressure and horizontal displacement.Keywords: Earthquake, numerical analysis, FLAC2D, displacement, Embankment Dam, pore water pressure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2451