Search results for: metaheuristic technique
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6623

Search results for: metaheuristic technique

4763 Phasor Measurement Unit Based on Particle Filtering

Authors: Rithvik Reddy Adapa, Xin Wang

Abstract:

Phasor Measurement Units (PMUs) are very sophisticated measuring devices that find amplitude, phase and frequency of various voltages and currents in a power system. Particle filter is a state estimation technique that uses Bayesian inference. Particle filters are widely used in pose estimation and indoor navigation and are very reliable. This paper studies and compares four different particle filters as PMUs namely, generic particle filter (GPF), genetic algorithm particle filter (GAPF), particle swarm optimization particle filter (PSOPF) and adaptive particle filter (APF). Two different test signals are used to test the performance of the filters in terms of responsiveness and correctness of the estimates.

Keywords: phasor measurement unit, particle filter, genetic algorithm, particle swarm optimisation, state estimation

Procedia PDF Downloads 9
4762 A Multi Function Myocontroller for Upper Limb Prostheses

Authors: Ayad Asaad Ibrahim

Abstract:

Myoelectrically controlled prostheses are becoming more and more popular, for below-elbow amputation, the wrist flexor and extensor muscle group, while for above-elbow biceps and triceps brachii muscles are used for control of the prosthesis. A two site multi-function controller is presented. Two stainless steel bipolar electrode pairs are used to monitor the activities in both muscles. The detected signals are processed by new pre-whitening technique to identify the accurate tension estimation in these muscles. These estimates will activate the relevant prosthesis control signal, with a time constant of 200 msec. It is ensured that the tension states in the control muscle to activate a particular prosthesis function are similar to those used to activate normal functions in the natural hand. This facilitates easier training.

Keywords: prosthesis, biosignal processing, pre-whitening, myoelectric controller

Procedia PDF Downloads 363
4761 Transmit Power Optimization for Cooperative Beamforming in Reverse-Link MIMO Ad-Hoc Networks

Authors: Younghyun Jeon, Seungjoo Maeng

Abstract:

In the Ad-hoc network, the great interests regarding MIMO scheme leads to their combination, which is also utilized into its applicable network. We manage the field of the problem into Reverse-link MIMO Ad-hoc Network (RMAN) and propose the methodology to maximize the data rate with its power consumption using Node-Cooperative beamforming technique. Based on the result of mathematical optimization formulation, we design the algorithm to construct optimal orthogonal weight vector according to channel feedback and control its transmission power according to QoS-pricing value level. In simulation results, we show the validity of the proposed mathematical optimization result and algorithm which mean that the sum-rate of each link is converged into some point.

Keywords: ad-hoc network, MIMO, cooperative beamforming, transmit power

Procedia PDF Downloads 398
4760 Community Empowerment: The Contribution of Network Urbanism on Urban Poverty Reduction

Authors: Lucia Antonela Mitidieri

Abstract:

This research analyzes the application of a model of settlements management based on networks of territorial integration that advocates planning as a cyclical and participatory process that engages early on with civic society, the private sector and the state. Through qualitative methods such as participant observation, interviews with snowball technique and an active research on territories, concrete results of community empowerment are obtained from the promotion of productive enterprises and community spaces of encounter and exchange. Studying the cultural and organizational dimensions of empowerment allows building indicators such as increase of capacities or community cohesion that can lead to support local governments in achieving sustainable urban development for a reduction of urban poverty.

Keywords: community spaces, empowerment, network urbanism, participatory process

Procedia PDF Downloads 331
4759 Deformulation and Comparative Analysis of Apparently Similar Polymers Using Multiple Modes of Pyrolysis-Gc/Ms

Authors: Athena Nguyen, Rojin Belganeh

Abstract:

Detecting and identifying differences in like polymer materials are key factors in deformulation, comparative analysis as well as reverse engineering. Pyrolysis-GC/MS is an easy solid sample introduction technique which expands the application areas of gas chromatography and mass spectrometry. The Micro-furnace pyrolyzer is directly interfaced with the GC injector preventing any potential of cold spot, carryover, and cross contamination. This presentation demonstrates the study of two similar polymers by performing different mode of operations in the same system: Evolve gas analysis (EGA), Flash pyrolysis, Thermal desorption analysis, and Heart-cutting analysis. Unknown polymer materials and their chemical compositions are identified.

Keywords: gas chromatography/mass spectrometry, pyrolysis, pyrolyzer, thermal desorption-GC/MS

Procedia PDF Downloads 264
4758 Copolymers of Pyrrole and α,ω-Dithienyl Terminated Poly(ethylene glycol)

Authors: Nesrin Köken, Esin A. Güvel, Nilgün Kızılcan

Abstract:

This work presents synthesis of α,ω-dithienyl terminated poly(ethylene glycol) (PEGTh) capable for further chain extension by either chemical or electrochemical polymerization. PEGTh was characterized by FTIR and 1H-NMR. Further, copolymerization of PEGTh and pyrrole (Py) was performed by chemical oxidative polymerization using ceric (IV) salt as an oxidant (PPy-PEGTh). PEG without end group modification was used directly to prepare copolymers with Py by Ce (IV) salt (PPy-PEG). Block copolymers with mole ratio of pyrrole to PEGTh (PEG) 50:1 and 10:1 were synthesized. The electrical conductivities of copolymers PPy-PEGTh and PPy-PEG were determined by four-point probe technique. Influence of the synthetic route and content of the insulating segment on conductivity and yield of the copolymers were investigated.

Keywords: chemical oxidative polymerization, conducting polymer, poly(ethylene glycol), polypyrrole

Procedia PDF Downloads 362
4757 Polymerization: An Alternative Technology for Heavy Metal Removal

Authors: M. S. Mahmoud

Abstract:

In this paper, the adsorption performance of a novel environmental friendly material, calcium alginate gel beads as a non-conventional technique for the successful removal of copper ions from aqueous solution are reported on. Batch equilibrium studies were carried out to evaluate the adsorption capacity and process parameters such as pH, adsorbent dosages, initial metal ion concentrations, stirring rates and contact times. It was observed that the optimum pH for maximum copper ions adsorption was at pH 5.0. For all contact times, an increase in copper ions concentration resulted in decrease in the percent of copper ions removal. Langmuir and Freundlich's isothermal models were used to describe the experimental adsorption. Adsorbent was characterization using Fourier transform-infrared (FT-IR) spectroscopy and Transmission electron microscopy (TEM).

Keywords: adsorption, alginate polymer, isothermal models, equilibrium

Procedia PDF Downloads 448
4756 Currency Exchange Rate Forecasts Using Quantile Regression

Authors: Yuzhi Cai

Abstract:

In this paper, we discuss a Bayesian approach to quantile autoregressive (QAR) time series model estimation and forecasting. Together with a combining forecasts technique, we then predict USD to GBP currency exchange rates. Combined forecasts contain all the information captured by the fitted QAR models at different quantile levels and are therefore better than those obtained from individual models. Our results show that an unequally weighted combining method performs better than other forecasting methodology. We found that a median AR model can perform well in point forecasting when the predictive density functions are symmetric. However, in practice, using the median AR model alone may involve the loss of information about the data captured by other QAR models. We recommend that combined forecasts should be used whenever possible.

Keywords: combining forecasts, MCMC, predictive density functions, quantile forecasting, quantile modelling

Procedia PDF Downloads 256
4755 Damping Optimal Design of Sandwich Beams Partially Covered with Damping Patches

Authors: Guerich Mohamed, Assaf Samir

Abstract:

The application of viscoelastic materials in the form of constrained layers in mechanical structures is an efficient and cost-effective technique for solving noise and vibration problems. This technique requires a design tool to select the best location, type, and thickness of the damping treatment. This paper presents a finite element model for the vibration of beams partially or fully covered with a constrained viscoelastic damping material. The model is based on Bernoulli-Euler theory for the faces and Timoshenko beam theory for the core. It uses four variables: the through-thickness constant deflection, the axial displacements of the faces, and the bending rotation of the beam. The sandwich beam finite element is compatible with the conventional C1 finite element for homogenous beams. To validate the proposed model, several free vibration analyses of fully or partially covered beams, with different locations of the damping patches and different percent coverage, are studied. The results show that the proposed approach can be used as an effective tool to study the influence of the location and treatment size on the natural frequencies and the associated modal loss factors. Then, a parametric study regarding the variation in the damping characteristics of partially covered beams has been conducted. In these studies, the effect of core shear modulus value, the effect of patch size variation, the thickness of constraining layer, and the core and the locations of the patches are considered. In partial coverage, the spatial distribution of additive damping by using viscoelastic material is as important as the thickness and material properties of the viscoelastic layer and the constraining layer. Indeed, to limit added mass and to attain maximum damping, the damping patches should be placed at optimum locations. These locations are often selected using the modal strain energy indicator. Following this approach, the damping patches are applied over regions of the base structure with the highest modal strain energy to target specific modes of vibration. In the present study, a more efficient indicator is proposed, which consists of placing the damping patches over regions of high energy dissipation through the viscoelastic layer of the fully covered sandwich beam. The presented approach is used in an optimization method to select the best location for the damping patches as well as the material thicknesses and material properties of the layers that will yield optimal damping with the minimum area of coverage.

Keywords: finite element model, damping treatment, viscoelastic materials, sandwich beam

Procedia PDF Downloads 147
4754 Efficient Positioning of Data Aggregation Point for Wireless Sensor Network

Authors: Sifat Rahman Ahona, Rifat Tasnim, Naima Hassan

Abstract:

Data aggregation is a helpful technique for reducing the data communication overhead in wireless sensor network. One of the important tasks of data aggregation is positioning of the aggregator points. There are a lot of works done on data aggregation. But, efficient positioning of the aggregators points is not focused so much. In this paper, authors are focusing on the positioning or the placement of the aggregation points in wireless sensor network. Authors proposed an algorithm to select the aggregators positions for a scenario where aggregator nodes are more powerful than sensor nodes.

Keywords: aggregation point, data communication, data aggregation, wireless sensor network

Procedia PDF Downloads 160
4753 The Quality Improvement of Painting Assignments for Grade 4-6 Students by Using PDCA Cycle

Authors: Pawinee Sorawech

Abstract:

The purpose of this study was to investigate the quality improvement of painting assignments for grade 4-6 students by using PDCA cycle. This study employed a qualitative technique. Suan Sunandha Rajabhat University and its demonstration school were selected as the area of study. An in-depth interview was utilized. The findings revealed that model of PDCA cycle was a proper model to increase the quality of painting assignments for grade 4-6 students. The six steps of improvement included: studying the PDCA model, setting up a plan, determining the scope of work, creating a strategy, developing a quality for painting assignment, and coming up with a handbook for a quality improvement of painting assignment.

Keywords: quality, painting assignments, PDCA cycle, grade 4-6 students

Procedia PDF Downloads 482
4752 Continuous Manufacturing of Ultra Fine Grained Materials by Severe Plastic Deformation Methods

Authors: Aslı Günay Bulutsuz, Mehmet Emin Yurci

Abstract:

Severe plastic deformation techniques are top-down deformation methods which enable superior mechanical properties by decreasing grain size. Different kind severe plastic deformation methods have been widely being used at various process temperature and geometries. Besides manufacturing advantages of severe plastic deformation technique, most of the types are being used only at the laboratory level. They cannot be adapted to industrial usage due to their continuous manufacturability and manufacturing costs. In order to enhance these manufacturing difficulties and enable widespread usage, different kinds of methods have been developed. In this review, a comprehensive literature research was fulfilled in order to highlight continuous severe plastic deformation methods.

Keywords: continuous manufacturing, severe plastic deformation, ultrafine grains, grain size refinement

Procedia PDF Downloads 236
4751 MCERTL: Mutation-Based Correction Engine for Register-Transfer Level Designs

Authors: Khaled Salah

Abstract:

In this paper, we present MCERTL (mutation-based correction engine for RTL designs) as an automatic error correction technique based on mutation analysis. A mutation-based correction methodology is proposed to automatically fix the erroneous RTL designs. The proposed strategy combines the processes of mutation and assertion-based localization. The erroneous statements are mutated to produce possible fixes for the failed RTL code. A concurrent mutation engine is proposed to mitigate the computational cost of running sequential mutants operators. The proposed methodology is evaluated against some benchmarks. The experimental results demonstrate that our proposed method enables us to automatically locate and correct multiple bugs at reasonable time.

Keywords: bug localization, error correction, mutation, mutants

Procedia PDF Downloads 280
4750 Determine of Design Variables and Target Reliability Indexes of Underground Structure

Authors: Yo-Seph Byun, Gyu-Phil Lee, Young-Bin Park, Gye-Chun Cho, Seong-Won Lee

Abstract:

In Korea, a study on Limit State Design (LSD) for underground structures is being conducted in order to perform more effective design. In this study, as a result of MCS (Monte-Carlo Simulation) technique, failure probabilities of the structure during normal and earthquake are estimated in reliability analysis. Target reliability indexes are determined depending on load combinations for underground structure, and then, design variables such as load and material factors in LSD are decided. As a result, through the research in order to determine more reliable design variables, a specification of LSD for underground structures is able to be developed.

Keywords: design variable, limit state design, target reliability index, underground structure

Procedia PDF Downloads 284
4749 The Effect of Arabic Gum on Polyethersulfone Membranes

Authors: Yehia Manawi, Viktor Kochkodan, Muataz Hussien

Abstract:

In this paper, the effect of adding Arabic Gum (AG) to the dope solutions of polyethersulfone (PES) was studied. The aim of adding AG is to enhance the properties of ultrafiltration membranes such as hydrophilicity, porosity and selectivity. several AG loading (0.1-3.0 wt.%) in PES/ N-Methyl-2-pyrrolidone (NMP) casting solutions were prepared to fabricate PES membranes using phase inversion technique. The surface morphology, hydrophilicity and selectivity of the cast PES/AG membranes were analyzed using scanning electron microscopy and contact angle measurements. The selectivity of the fabricated membranes was also tested by filtration of oil solutions (1 ppm) and found to show quite high removal efficiency. The effect of adding AG to PES membranes was found to increase the permeate flux and porosity as well as reducing surface roughness and the contact angle of the membranes.

Keywords: antifouling, Arabic gum, polyethersulfone membrane, ultrafiltration

Procedia PDF Downloads 285
4748 Technical, Functional, and Behavioural Aspects and Their Attributes in Survey Questionnaire for Post Occupancy Evaluation of Residential Hostels

Authors: Meenal Kumar

Abstract:

The structure of a questionnaire becomes critical in gathering accurate feedback in a post-occupancy evaluation of a building. A survey instrument like this one consists of questions based on various aspects of a constructed facility. The questions and the qualities reflect the goals and determine the nature of the survey, which can be classified into several types. Therefore, a survey instrument uses appropriately described attributes. This ongoing research aims to provide an appropriate technique for framing the Questionnaire, taking into account the relevant aspects of the study and its defining features that analyze building performance from the user's perspective, which can further benefit the architects, planners, and designers in designing user-friendly spaces.

Keywords: post occupancy evaluations, satisfaction, attributes, survey, building performance evaluations

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4747 Superconducting Properties of Fe Doped in Cu-Site of Bi1.6Pb0.4Sr2Ca2Cu3-xFexOy

Authors: M. A. Suazlina, H. Azhan, S. A. Syamsyir, S. Y. S. Yusainee

Abstract:

Fe2O3 was doped to Bi-2223 superconductor prepared in bulk form using high purity oxide powders via solid state reaction technique with intermediate grinding. A stiochiometric of x=0.00, 0.02, 0.04, 0.06, 0.08 and 0.10 Fe are systematically added to the well balanced Bi1.6Pb0.4Sr2Ca2Cu3-xFexOy in order to trace the effect of Fe doping to the system. Microstructure, resistive transitions, phase volume, and cell parameters were hence investigated. Substitution of Fe is found to slowly decrease the Bi-2223 phase volume and the resistive transitions for x=0.00 – 0.10 samples whereas accelerated formation of the Bi-2212 phase is detected for further substitutions. Changes in superconducting properties of Fe-doping Bi-2223 system were discussed and the findings were further compared with available literature.

Keywords: BSCCO, critical temperature, critical current density, XRD, flux pinning

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4746 An Application of Modified M-out-of-N Bootstrap Method to Heavy-Tailed Distributions

Authors: Hannah F. Opayinka, Adedayo A. Adepoju

Abstract:

This study is an extension of a prior study on the modification of the existing m-out-of-n (moon) bootstrap method for heavy-tailed distributions in which modified m-out-of-n (mmoon) was proposed as an alternative method to the existing moon technique. In this study, both moon and mmoon techniques were applied to two real income datasets which followed Lognormal and Pareto distributions respectively with finite variances. The performances of these two techniques were compared using Standard Error (SE) and Root Mean Square Error (RMSE). The findings showed that mmoon outperformed moon bootstrap in terms of smaller SEs and RMSEs for all the sample sizes considered in the two datasets.

Keywords: Bootstrap, income data, lognormal distribution, Pareto distribution

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4745 Improving Equipment Life and Overall Equipment Effectiveness (O.E.E.) through Proper Maintenance Strategy Using Value Engineering

Authors: Malay Niraj, Praveen Kumar

Abstract:

The present study is a new approach for improving equipment life and Overall Equipment Efficiency (O.E.E.) through suitable maintenance practice with the help of value engineering. Value engineering is a one of the most powerful decision-making techniques which depend on many factors. The improvements are the result of recommendations made by multidisciplinary teams representing all parties involved. VE is a rigorous, systematic effort to improve the OEE and optimize the life cycle cost of a facility. The study describes problems in maintenance arising due to the absence of having clear criteria and strong decision constrain how to maintain failing equipment. Using factor comparisons, the study has been made between different maintenance practices and finally best maintenance practice based on value engineering technique has been selected.

Keywords: maintenance strategy, overall equipment efficiency, value engineering, decision-making

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4744 Interrelationship between Quadriceps' Activation and Inhibition as a Function of Knee-Joint Angle and Muscle Length: A Torque and Electro and Mechanomyographic Investigation

Authors: Ronald Croce, Timothy Quinn, John Miller

Abstract:

Incomplete activation, or activation failure, of motor units during maximal voluntary contractions is often referred to as muscle inhibition (MI), and is defined as the inability of the central nervous system to maximally drive a muscle during a voluntary contraction. The purpose of the present study was to assess the interrelationship amongst peak torque (PT), muscle inhibition (MI; incomplete activation of motor units), and voluntary muscle activation (VMA) of the quadriceps’ muscle group as a function of knee angle and muscle length during maximal voluntary isometric contractions (MVICs). Nine young adult males (mean + standard deviation: age: 21.58 + 1.30 years; height: 180.07 + 4.99 cm; weight: 89.07 + 7.55 kg) performed MVICs in random order with the knee at 15, 55, and 95° flexion. MI was assessed using the interpolated twitch technique and was estimated by the amount of additional knee extensor PT evoked by the superimposed twitch during MVICs. Voluntary muscle activation was estimated by root mean square amplitude electromyography (EMGrms) and mechanomyography (MMGrms) of agonist (vastus medialis [VM], vastus lateralis [VL], and rectus femoris [RF]) and antagonist (biceps femoris ([BF]) muscles during MVICs. Data were analyzed using separate repeated measures analysis of variance. Results revealed a strong dependency of quadriceps’ PT (p < 0.001), MI (p < 0.001) and MA (p < 0.01) on knee joint position: PT was smallest at the most shortened muscle position (15°) and greatest at mid-position (55°); MI and MA were smallest at the most shortened muscle position (15°) and greatest at the most lengthened position (95°), with the RF showing the greatest change in MA. It is hypothesized that the ability to more fully activate the quadriceps at short compared to longer muscle lengths (96% contracted at 15°; 91% at 55°; 90% at 95°) might partly compensate for the unfavorable force-length mechanics at the more extended position and consequent declines in VMA (decreases in EMGrms and MMGrms muscle amplitude during MVICs) and force production (PT = 111-Nm at 15°, 217-NM at 55°, 199-Nm at 95°). Biceps femoris EMG and MMG data showed no statistical differences (p = 0.11 and 0.12, respectively) at joint angles tested, although there were greater values at the extended position. Increased BF muscle amplitude at this position could be a mechanism by which anterior shear and tibial rotation induced by high quadriceps’ activity are countered. Measuring and understanding the degree to which one sees MI and VMA in the QF muscle has particular clinical relevance because different knee-joint disorders, such ligament injuries or osteoarthritis, increase levels of MI observed and markedly reduced the capability of full VMA.

Keywords: electromyography, interpolated twitch technique, mechanomyography, muscle activation, muscle inhibition

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4743 Pedestrian Safe Bumper Design from Commingled Glass Fiber/Polypropylene Reinforced Sandwich Composites

Authors: L. Onal

Abstract:

The aim of this study is to optimize manufacturing process for thermoplastic sandwich composite structures for the pedestrian safety of automobiles subjected to collision condition. In particular, cost-effective manufacturing techniques for sandwich structures with commingled GF/PP skins and low-density foam cores are being investigated. The performance of these structures under bending load is being studied. Samples are manufactured using compression moulding technique. The relationship of this performance to processing parameters such as mould temperature, moulding time, moulding pressure and sequence of the layers during moulding is being investigated. The results of bending tests are discussed in the light of the moulding conditions and conclusions are given regarding optimum set of processing conditions using the compression moulding route

Keywords: twintex, flexural properties, automobile composites, sandwich structures

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4742 A Survey on Intelligent Techniques Based Modelling of Size Enlargement Process for Fine Materials

Authors: Mohammad Nadeem, Haider Banka, R. Venugopal

Abstract:

Granulation or agglomeration is a size enlargement process to transform the fine particulates into larger aggregates since the fine size of available materials and minerals poses difficulty in their utilization. Though a long list of methods is available in the literature for the modeling of granulation process to facilitate the in-depth understanding and interpretation of the system, there is still scope of improvements using novel tools and techniques. Intelligent techniques, such as artificial neural network, fuzzy logic, self-organizing map, support vector machine and others, have emerged as compelling alternatives for dealing with imprecision and complex non-linearity of the systems. The present study tries to review the applications of intelligent techniques in the modeling of size enlargement process for fine materials.

Keywords: fine material, granulation, intelligent technique, modelling

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4741 A SiGe Low Power RF Front-End Receiver for 5.8GHz Wireless Biomedical Application

Authors: Hyunwon Moon

Abstract:

It is necessary to realize new biomedical wireless communication systems which send the signals collected from various bio sensors located at human body in order to monitor our health. Also, it should seamlessly connect to the existing wireless communication systems. A 5.8 GHz ISM band low power RF front-end receiver for a biomedical wireless communication system is implemented using a 0.5 µm SiGe BiCMOS process. To achieve low power RF front-end, the current optimization technique for selecting device size is utilized. The implemented low noise amplifier (LNA) shows a power gain of 9.8 dB, a noise figure (NF) of below 1.75 dB, and an IIP3 of higher than 7.5 dBm while current consumption is only 6 mA at supply voltage of 2.5 V. Also, the performance of a down-conversion mixer is measured as a conversion gain of 11 dB and SSB NF of 10 dB.

Keywords: biomedical, LNA, mixer, receiver, RF front-end, SiGe

Procedia PDF Downloads 317
4740 The Management of Radio Spectrum Resources in Thailand

Authors: Pongsawee Supanonth

Abstract:

This research is the study of Spectrum Management and the increase in efficiency of Spectrum Utilization. It also proves that Cognitive Radio is a newer technology that will change the face of e-communications network today. This study used qualitative research methods by using in-depth interviews to collect data from a sample specific to those who work in Radio channel from 6 key informant and literature review from the related documents in online database. The result is the technique of Dynamic Spectrum Allocation that is the most suitable for Thailand. We conduct in-depth research for future purposes. Moreover, we can also develop a model that can be used in regulating and managing spectrum that is most suitable for Thailand. And also develop an important tool which can be of importance to allocation of spectrum as a natural resource appropriately. It will also guarantee quality and high benefit in a substantial way.

Keywords: cognitive radio, management of radio spectrum, spectrum management, spectrum scarcity

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4739 Innovative Acoustic Emission Techniques for Concrete Health Monitoring

Authors: Rahmat Ali, Beenish Khan, Aftabullah, Abid A. Shah

Abstract:

This research is an attempt to investigate the wide range of events using acoustic emission (AE) sensors of the concrete cubes subjected to different stress condition loading and unloading of concrete cubes. A total of 27 specimens were prepared and tested including 18 cubic (6”x6”x6”) and nine cylindrical (4”x8”) specimens were molded from three batches of concrete using w/c of 0.40, 0.50, and 0.60. The compressive strength of concrete was determined from concrete cylinder specimens. The deterioration of concrete was evaluated using the occurrence of felicity and Kaiser effects at each stress condition. It was found that acoustic emission hits usually exceeded when damage increases. Additionally, the correlation between AE techniques and the load applied were determined by plotting the normalized values. The influence of w/c on sensitivity of the AE technique in detecting concrete damages was also investigated.

Keywords: acoustic emission, concrete, felicity ratio, sensors

Procedia PDF Downloads 362
4738 Studies On Triazole Resistant Candida Albicans Expressing ERG11 Gene Among Adult Females In Abakaliki; Nigeria

Authors: Agumah N. B. Orji, M. U., Oru C. M., Ugbo, E. N., Onwuliri E. A Nwakaeze, E. A.,

Abstract:

ERG11 gene has been reported to be one of the genes whose expression is responsible for resistance of Candida to various triazole drugs, which are first line treatment for candidiasis. This study was carried out to determine the prevalence of Triazole (Fluconazole and voriconazole) resistant Candida albicans expressing ERG11 gene from adult females in Abakaliki. Urine and vaginal swab samples were randomly collected from volunteers after obtaining their consent to participate in the study. A total of 565 adult females participated in the study. A total of 340 urine specimens and 288 vaginal swab specimens were collected. Direct wet mount technique, as well as culture in Trichomonas broth, were used to examine the urine and vaginal swab specimens for the presence of motile Trichomonads. The Trichomonas broth used was selective for both T. vaginalis and C. albicans. Broths that yielded budding yeast cells after microscopy were subcultured on to Sabouraud dextrose agar, after which Germ tube test was carried out to confirm the presence of C. albicans. Biochemical tests, including carbohydrate fermentation and urease utilization, were also performed. Antibiogram of C. albicans isolates obtained from this study was carried out using commercially available azole drugs. Fluconazole and voriconazole were selected as Triazole drugs used for this study. Nystatin was used as a tangential control. An MIC test was carried out with E-strips on some of the resistant C. albicans isolates A total of 6 isolates that resisted all the azole drugs were selected and screened for the presence of ERG11 gene using Reverse transcriptase polymerase chain reaction technique. The total prevalence recorded for C. albicans was 13.0%. Frequency was statistically higher in Pregnant (7.96%) than non pregnant (5.09%) volunteers (X2=0.94 at P=0.05). With respect to clinical samples, frequency was higher in vaginal swabs samples (7.96%) than Urine samples (5.09%) (X2=9.05 at P=0.05). Volunteers within the age group 26-30 years recorded the highest prevalence (4.46%), while those within the age group 36-40 years recorded the lowest at 1.27%(X2=4.34 at P=0.05). In pregnant female participants, the highest frequency was recorded with those in their 3rd trimester (4.14%), while lowest incidence was recorded for those in their first trimester (0.80%). Antibiogram results from this study showed that C. albicans isolates obtained from this study resisted Fluconazole (72%) more than Voriconazole (57%). Only one out of the six selected isolates yielded resistance in the MIC test. Results obtained from the RT-PCR showed that there was no expression of ERG11 gene among the fluconazole resistant isolates of C. albicans. Observed resistance may be due to other factors other than expression of ERG11 gene.

Keywords: candida, ERG11, triazole, nigeria

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4737 How Consumers Perceive Health and Nutritional Information and How It Affects Their Purchasing Behavior: Comparative Study between Colombia and the Dominican Republic

Authors: Daniel Herrera Gonzalez, Maria Luisa Montas

Abstract:

There are some factors affecting consumer decision-making regarding the use of the front of package labels in order to find benefits to the well-being of the human being. Currently, there are several labels that help influence or change the purchase decision for food products. These labels communicate the impact that food has on human health; therefore, consumers are more critical and intelligent when buying and consuming food products. The research explores the association between front-of-pack labeling and food choice; the association between label content and purchasing decisions is complex and influenced by different factors, including the packaging itself. The main objective of this study was to examine the perception of health labels and nutritional declarations and their influence on buying decisions in the non-alcoholic beverages sector. This comparative study of two developing countries will show how consumers take nutritional labels into account when deciding to buy certain foods. This research applied a quantitative methodology with correlational scope. This study has a correlational approach in order to analyze the degree of association between variables. Likewise, the confirmatory factor analysis (CFA) method and structural equation modeling (SEM) as a powerful multivariate technique was used as statistical technique to find the relationships between observable and unobservable variables. The main findings of this research were the obtaining of three large groups and their perception and effects on nutritional and wellness labels. The first group is characterized by taking an attitude of high interest on the issue of the imposition of the nutritional information label on products and would agree that all products should be packaged given its importance to preventing illnesses in the consumer. Likewise, they almost always care about the brand, the size, the list of ingredients, and nutritional information of the food, and also the effect of these on health. The second group stands out for presenting some interest in the importance of the label on products as a purchase decision, in addition to almost always taking into account the characteristics of size, money, components, etc. of the products to decide on their consumption and almost always They are never interested in the effect of these products on their health or nutrition, and in group 3, it differs from the others by being more neutral regarding the issue of nutritional information labels, and being less interested in the purchase decision and characteristics of the product and also on the influence of these on health and nutrition. This new knowledge is essential for different companies that manufacture and market food products because they will have information to adapt or anticipate the new laws of developing countries as well as the new needs of health-conscious consumers when they buy food products.

Keywords: healthy labels, consumer behavior, nutritional information, healthy products

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4736 Performance Evaluation of Distributed and Co-Located MIMO LTE Physical Layer Using Wireless Open-Access Research Platform

Authors: Ishak Suleiman, Ahmad Kamsani Samingan, Yeoh Chun Yeow, Abdul Aziz Bin Abdul Rahman

Abstract:

In this paper, we evaluate the benefits of distributed 4x4 MIMO LTE downlink systems compared to that of the co-located 4x4 MIMO LTE downlink system. The performance evaluation was carried out experimentally by using Wireless Open-Access Research Platform (WARP), where the comparison between the 4x4 MIMO LTE transmission downlink system in distributed and co-located techniques was examined. The measured Error Vector Magnitude (EVM) results showed that the distributed technique achieved better system performance compared to the co-located arrangement.

Keywords: multiple-input-multiple-output (MIMO), distributed MIMO, co-located MIMO, LTE

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4735 Application of the Material Point Method as a New Fast Simulation Technique for Textile Composites Forming and Material Handling

Authors: Amir Nazemi, Milad Ramezankhani, Marian Kӧrber, Abbas S. Milani

Abstract:

The excellent strength to weight ratio of woven fabric composites, along with their high formability, is one of the primary design parameters defining their increased use in modern manufacturing processes, including those in aerospace and automotive. However, for emerging automated preform processes under the smart manufacturing paradigm, complex geometries of finished components continue to bring several challenges to the designers to cope with manufacturing defects on site. Wrinklinge. g. is a common defectoccurring during the forming process and handling of semi-finished textile composites. One of the main reasons for this defect is the weak bending stiffness of fibers in unconsolidated state, causing excessive relative motion between them. Further challenges are represented by the automated handling of large-area fiber blanks with specialized gripper systems. For fabric composites forming simulations, the finite element (FE)method is a longstanding tool usedfor prediction and mitigation of manufacturing defects. Such simulations are predominately meant, not only to predict the onset, growth, and shape of wrinkles but also to determine the best processing condition that can yield optimized positioning of the fibers upon forming (or robot handling in the automated processes case). However, the need for use of small-time steps via explicit FE codes, facing numerical instabilities, as well as large computational time, are among notable drawbacks of the current FEtools, hindering their extensive use as fast and yet efficient digital twins in industry. This paper presents a novel woven fabric simulation technique through the application of the material point method (MPM), which enables the use of much larger time steps, facing less numerical instabilities, hence the ability to run significantly faster and efficient simulationsfor fabric materials handling and forming processes. Therefore, this method has the ability to enhance the development of automated fiber handling and preform processes by calculating the physical interactions with the MPM fiber models and rigid tool components. This enables the designers to virtually develop, test, and optimize their processes based on either algorithmicor Machine Learning applications. As a preliminary case study, forming of a hemispherical plain weave is shown, and the results are compared to theFE simulations, as well as experiments.

Keywords: material point method, woven fabric composites, forming, material handling

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4734 The Effectiveness of Lesson Study via Learning Communities in Increasing Instructional Self-Efficacy of Beginning Special Educators

Authors: David D. Hampton

Abstract:

Lesson study is used as an instructional technique to promote both student and faculty learning. However, little is known about the usefulness of learning communities in supporting results of lesson study on the self-efficacy and development for tenure-track faculty. This study investigated the impact of participation in a lesson study learning community on 34 new faculty members at a mid-size Midwestern University, specifically regarding implementing lesson study evaluations by new faculty on their reported self-efficacy. Results indicate that participation in a lesson study learning community significantly increased faculty members’ lesson study self-efficacy as well as grant and manuscript production over one academic year. Suggestions for future lesson study around faculty learning communities are discussed.

Keywords: lesson study, learning community, lesson study self-efficacy, new faculty

Procedia PDF Downloads 150