Search results for: brine method
10264 Synthesis and in-Vitro Biological Activity of Novel Gallic Acid Derivatives
Authors: Hossein Mostafavi
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A diversity of biological activities and pharmaceutical uses have been attributed to gallic acid derivatives such as antibacterial, anticancer, anti inflammatory. A series of gallic acid derivatives were synthesized, and their structure was confirmed by FT-IR, HNMR, CNMR, elemental analysis. In vitro biological activity of compounds was determined against Proteus vulgaris ATCC 7829, Escherichia coli ATCC 25922, as (Gram-negative) bacteria and bacillus cereus ATCC 11778, Staphylococus aureus ATCC 6538 as (Gram-positive) bacteria. Antibacterial susceptibility tests were done by use of the paper disc diffusion method on Mueller Hinton agar (Merck). Chloramiphenicol, Penicilline, Streptomycin and Tetracycline were standard reference antibiotics. The zone of inhibition against bacteria was measured after 24 hours at 37 °C. Compounds 3, 4, 5 were the main antibacterial compounds against Gram-negative bacteria but not Gram-positive.Keywords: gallic acid derivatives, antibacterial, antibiotics, inhibition
Procedia PDF Downloads 13610263 Fast and Robust Long-term Tracking with Effective Searching Model
Authors: Thang V. Kieu, Long P. Nguyen
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Kernelized Correlation Filter (KCF) based trackers have gained a lot of attention recently because of their accuracy and fast calculation speed. However, this algorithm is not robust in cases where the object is lost by a sudden change of direction, being obscured or going out of view. In order to improve KCF performance in long-term tracking, this paper proposes an anomaly detection method for target loss warning by analyzing the response map of each frame, and a classification algorithm for reliable target re-locating mechanism by using Random fern. Being tested with Visual Tracker Benchmark and Visual Object Tracking datasets, the experimental results indicated that the precision and success rate of the proposed algorithm were 2.92 and 2.61 times higher than that of the original KCF algorithm, respectively. Moreover, the proposed tracker handles occlusion better than many state-of-the-art long-term tracking methods while running at 60 frames per second.Keywords: correlation filter, long-term tracking, random fern, real-time tracking
Procedia PDF Downloads 13710262 Online Shopping vs Privacy – Results of an Experimental Study
Authors: Andrzej Poszewiecki
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The presented paper contributes to the experimental current of research on privacy. The question of privacy is being discussed at length at present, primarily among lawyers and politicians. However, the matter of privacy has been of interest for economists for some time as well. The valuation of privacy by people is of great importance now. This article is about how people valuate their privacy. An experimental method has been utilised in the conducted research – the survey was carried out among customers of an online store, and the studied issue was whether their readiness to sell their data (WTA) was different from the willingness to buy data back (WTP). The basic aim of this article is to analyse whether people shopping on the Internet differentiate their privacy depending on whether they protect or sell it. The achieved results indicate the presence of major differences in this respect, which do not always come up with the original expectations. The obtained results have supported the hypothesis that people are more willing to sell their data than to repurchase them. However, the hypothesis that the value of proposed remuneration affects the willingness to sell/buy back personal data (one’s privacy) has not been supported.Keywords: privacy, experimental economics, behavioural economics, internet
Procedia PDF Downloads 29210261 Image Instance Segmentation Using Modified Mask R-CNN
Authors: Avatharam Ganivada, Krishna Shah
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The Mask R-CNN is recently introduced by the team of Facebook AI Research (FAIR), which is mainly concerned with instance segmentation in images. Here, the Mask R-CNN is based on ResNet and feature pyramid network (FPN), where a single dropout method is employed. This paper provides a modified Mask R-CNN by adding multiple dropout methods into the Mask R-CNN. The proposed model has also utilized the concepts of Resnet and FPN to extract stage-wise network feature maps, wherein a top-down network path having lateral connections is used to obtain semantically strong features. The proposed model produces three outputs for each object in the image: class label, bounding box coordinates, and object mask. The performance of the proposed network is evaluated in the segmentation of every instance in images using COCO and cityscape datasets. The proposed model achieves better performance than the state-of-the-networks for the datasets.Keywords: instance segmentation, object detection, convolutional neural networks, deep learning, computer vision
Procedia PDF Downloads 7210260 Sliding Mode Position Control for Permanent Magnet Synchronous Motors Based on Passivity Approach
Authors: Jenn-Yih Chen, Bean-Yin Lee, Yuan-Chuan Hsu, Jui-Cheng Lin, Kuang-Chyi Lee
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In this paper, a sliding mode control method based on the passivity approach is proposed to control the position of surface-mounted permanent magnet synchronous motors (PMSMs). Firstly, the dynamics of a PMSM was proved to be strictly passive. The position controller with an adaptive law was used to estimate the load torque to eliminate the chattering effects associated with the conventional sliding mode controller. The stability analysis of the overall position control system was carried out by adopting the passivity theorem instead of Lyapunov-type arguments. Finally, experimental results were provided to show that the good position tracking can be obtained, and exhibit robustness in the variations of the motor parameters and load torque disturbances.Keywords: adaptive law, passivity theorem, permanent magnet synchronous motor, sliding mode control
Procedia PDF Downloads 46810259 Development of an Index for Asset Class in Ex-Ante Portfolio Management
Authors: Miang Hong Ngerng, Noor Diyana Jasme, May Jin Theong
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Volatile market environment is inevitable. Fund managers are struggling to choose the right strategy to survive and overcome uncertainties and adverse market movement. Therefore, finding certainty in the mist of uncertainty future is one of the key performance objectives for fund managers. Current available theoretical results are not practical due to strong reliance on the investment assumption made. This paper is to identify the component that can be forecasted in Ex-ante setting which is the realistic situation facing a fund manager in the actual execution of asset allocation in portfolio management. Partial lease square method was used to generate an index with 10 years accounting data from 191 companies listed in KLSE. The result shows that the index reflects the inner nature of the business and up to 30% of the stock return can be explained by the index.Keywords: active portfolio management, asset allocation ex-ante investment, asset class, partial lease square
Procedia PDF Downloads 26910258 Development of Three-Dimensional Bio-Reactor Using Magnetic Field Stimulation to Enhance PC12 Cell Axonal Extension
Authors: Eiji Nakamachi, Ryota Sakiyama, Koji Yamamoto, Yusuke Morita, Hidetoshi Sakamoto
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The regeneration of injured central nerve network caused by the cerebrovascular accidents is difficult, because of poor regeneration capability of central nerve system composed of the brain and the spinal cord. Recently, new regeneration methods such as transplant of nerve cells and supply of nerve nutritional factor were proposed and examined. However, there still remain many problems with the canceration of engrafted cells and so on and it is strongly required to establish an efficacious treating method of a central nerve system. Blackman proposed the electromagnetic stimulation method to enhance the axonal nerve extension. In this study, we try to design and fabricate a new three-dimensional (3D) bio-reactor, which can load a uniform AC magnetic field stimulation on PC12 cells in the extracellular environment for enhancement of an axonal nerve extension and 3D nerve network generation. Simultaneously, we measure the morphology of PC12 cell bodies, axons, and dendrites by the multiphoton excitation fluorescence microscope (MPM) and evaluate the effectiveness of the uniform AC magnetic stimulation to enhance the axonal nerve extension. Firstly, we designed and fabricated the uniform AC magnetic field stimulation bio-reactor. For the AC magnetic stimulation system, we used the laminated silicon steel sheets for a yoke structure of 3D chamber, which had a high magnetic permeability. Next, we adopted the pole piece structure and installed similar specification coils on both sides of the yoke. We searched an optimum pole piece structure using the magnetic field finite element (FE) analyses and the response surface methodology. We confirmed that the optimum 3D chamber structure showed a uniform magnetic flux density in the PC12 cell culture area by using FE analysis. Then, we fabricated the uniform AC magnetic field stimulation bio-reactor by adopting analytically determined specifications, such as the size of chamber and electromagnetic conditions. We confirmed that measurement results of magnetic field in the chamber showed a good agreement with FE results. Secondly, we fabricated a dish, which set inside the uniform AC magnetic field stimulation of bio-reactor. PC12 cells were disseminated with collagen gel and could be 3D cultured in the dish. The collagen gel were poured in the dish. The collagen gel, which had a disk shape of 6 mm diameter and 3mm height, was set on the membrane filter, which was located at 4 mm height from the bottom of dish. The disk was full filled with the culture medium inside the dish. Finally, we evaluated the effectiveness of the uniform AC magnetic field stimulation to enhance the nurve axonal extension. We confirmed that a 6.8 increase in the average axonal extension length of PC12 under the uniform AC magnetic field stimulation at 7 days culture in our bio-reactor, and a 24.7 increase in the maximum axonal extension length. Further, we confirmed that a 60 increase in the number of dendrites of PC12 under the uniform AC magnetic field stimulation. Finally, we confirm the availability of our uniform AC magnetic stimulation bio-reactor for the nerve axonal extension and the nerve network generation.Keywords: nerve regeneration, axonal extension , PC12 cell, magnetic field, three-dimensional bio-reactor
Procedia PDF Downloads 16810257 Nonparametric Specification Testing for the Drift of the Short Rate Diffusion Process Using a Panel of Yields
Authors: John Knight, Fuchun Li, Yan Xu
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Based on a new method of the nonparametric estimator of the drift function, we propose a consistent test for the parametric specification of the drift function in the short rate diffusion process using observations from a panel of yields. The test statistic is shown to follow an asymptotic normal distribution under the null hypothesis that the parametric drift function is correctly specified, and converges to infinity under the alternative. Taking the daily 7-day European rates as a proxy of the short rate, we use our test to examine whether the drift of the short rate diffusion process is linear or nonlinear, which is an unresolved important issue in the short rate modeling literature. The testing results indicate that none of the drift functions in this literature adequately captures the dynamics of the drift, but nonlinear specification performs better than the linear specification.Keywords: diffusion process, nonparametric estimation, derivative security price, drift function and volatility function
Procedia PDF Downloads 36810256 Text Similarity in Vector Space Models: A Comparative Study
Authors: Omid Shahmirzadi, Adam Lugowski, Kenneth Younge
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Automatic measurement of semantic text similarity is an important task in natural language processing. In this paper, we evaluate the performance of different vector space models to perform this task. We address the real-world problem of modeling patent-to-patent similarity and compare TFIDF (and related extensions), topic models (e.g., latent semantic indexing), and neural models (e.g., paragraph vectors). Contrary to expectations, the added computational cost of text embedding methods is justified only when: 1) the target text is condensed; and 2) the similarity comparison is trivial. Otherwise, TFIDF performs surprisingly well in other cases: in particular for longer and more technical texts or for making finer-grained distinctions between nearest neighbors. Unexpectedly, extensions to the TFIDF method, such as adding noun phrases or calculating term weights incrementally, were not helpful in our context.Keywords: big data, patent, text embedding, text similarity, vector space model
Procedia PDF Downloads 17510255 Inhibition of Pipelines Corrosion Using Natural Extracts
Authors: Eman Alzahrani, Hala M. Abo-Dief, Ashraf T. Mohamed
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The present work is aimed at examining carbon steel oil pipelines corrosion using three natural extracts (Eruca Sativa, Rosell and Mango peels) that are used as inhibitors of different concentrations ranging from 0.05-0.1wt. %. Two sulphur compounds are used as corrosion mediums. Weight loss method was used for measuring the corrosion rate of the carbon steel specimens immersed in technical white oil at 100ºC at various time intervals in absence and presence of the two sulphur compounds. The corroded specimens are examined using the chemical wear test, scratch test and hardness test. The scratch test is carried out using scratch loads from 0.5 Kg to 2.0 Kg. The scratch width is obtained at various scratch load and test conditions. The Brinell hardness test is carried out and investigated for both corroded and inhibited specimens. The results showed that three natural extracts can be used as environmentally friendly corrosion inhibitors.Keywords: inhibition, natural extract, oil pipelines corrosion, sulphur compounds
Procedia PDF Downloads 50710254 A Study on the Development of Social Participation Activity Scale for the Elderly
Authors: Young-Kwang Lee, Eun-Gu Ji, Min-Joo Kim, Seung-Jae Oh
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The purpose of this study is to develop a social participation activity scale for the elderly. As a result of exploratory factor analysis, confirmatory factor analysis was conducted using maximum likelihood method using bundled items. In conclusion, thirteen items of social participation activity scale seemed appropriate. Finally, convergent validity and discriminant validity were verified on the scale with the fit. The convergent validity was based on the variance extracted value. In other words, the hypothesis that the variables are the same is rejected and the validity is confirmed. This study extensively considered the measurement items of the social participation activity scale used to measure social participation activities of the elderly. In the future, it will be meaningful that it can be used as a tool to verify the effectiveness of services in organizations that provide social welfare services to elderly people such as comprehensive social welfare centers and the elderly comprehensive social welfare centers.Keywords: elderly, social participation, scale development, validity
Procedia PDF Downloads 18910253 High Efficiency Perovskite Solar Cells Fabricated under Ambient Conditions with Mesoporous TiO2/In2O3 Scaffold
Authors: A. Apostolopoulou, D. Sygkridou, A. N. Kalarakis, E. Stathatos
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Mesoscopic perovskite solar cells (mp-PSCs) with mesoporous bilayer were fabricated under ambient conditions. The bilayer was formed by capping the mesoporous TiO2 layer with a layer of In2O3. CH3NH3I3-xClx mixed halide perovskite was prepared through the one-step method and was used as the light absorber. The mp-PSCs with the composite TiO2/In2O3 mesoporous layer exhibited optimized electrical parameters, compared with the PSCs that employed only a TiO2 mesoporous layer, with a current density of 23.86 mA/cm2, open circuit voltage of 0.863 V, fill factor of 0.6 and a power conversion efficiency of 11.2%. These results indicate that the formation of a proper semiconductor capping layer over the basic TiO2 mesoporous layer can facilitate the electron transfer, suppress the recombination and subsequently lead to higher charge collection efficiency.Keywords: ambient conditions, high efficiency solar cells, mesoscopic perovskite solar cells, TiO₂ / In₂O₃ bilayer
Procedia PDF Downloads 27010252 Effects of Cattaneo-Christov Heat Flux on 3D Magnetohydrodynamic Viscoelastic Fluid Flow with Variable Thermal Conductivity
Authors: Muhammad Ramzan
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A mathematical model has been envisaged to discuss three-dimensional Viscoelastic fluid flow with an effect of Cattaneo-Christov heat flux in attendance of magnetohydrodynamic (MHD). Variable thermal conductivity with the impact of homogeneous-heterogeneous reactions and convective boundary condition is also taken into account. Homotopy analysis method is engaged to obtain series solutions. Graphical illustrations depicting behaviour of sundry parameters on skin friction coefficient and all involved distributions are also given. It is observed that velocity components are decreasing functions of Viscoelastic fluid parameter. Furthermore, strength of homogeneous and heterogeneous reactions have opposite effects on concentration distribution. A comparison with a published paper has also been established and an excellent agreement is obtained; hence reliable results are being presented.Keywords: Cattaneo Christov heat flux, homogenous-heterogeneous reactions, magnetic field, variable thermal conductivity
Procedia PDF Downloads 19710251 Evaluation of the Efficacy of Titanium Alloy Dental Implants Coated by Bio-ceramic Apatite Wollastonite (Aw) and Hydroxyapatite (Ha) by Pulsed Laser Deposition
Authors: Betsy S. Thomas, Manjeet Marpara, K. M. Bhat
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Introduction: After the initial enthusiasm and interest in hydroxyapatite products subsided due to dissolution of the coating and failure at the coating interface, this was a unique attempt to create a next generation of dental implant. Materials and Methods: The adhesion property of AW and HA coatings at various temperature by pulsed laser deposition was assessed on titanium plates. Moreover, AW/HA coated implants implanted in the femur of the rabbits was evaluated at various intervals. Results: Decohesion load was more for AW in scratch test and more bone formation around AW coated implants on histological evaluation. Discussion: AW coating by pulsed laser deposition was more adherent to the titanium surface and led to faster bone formation than HA. Conclusion: This experiment opined that AW coated by pulsed laser deposition seems to be a promising method in achieving bioactive coatings on titanium implants.Keywords: surface coating, dental implants, osseo integration, biotechnology
Procedia PDF Downloads 36510250 Pulsed Electric Field as Pretreatment for Different Drying Method in Chilean Abalone (Concholepas Concholepas) Mollusk: Effects on Product Physical Properties and Drying Methods Sustainability
Authors: Luis González-Cavieres, Mario Perez-Won, Anais Palma-Acevedo, Gipsy Tabilo-Munizaga, Erick Jara-Quijada, Roberto Lemus-Mondaca
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In this study, pulsed electric field (PEF: 2.0 kV/cm) was used as pretreatment in drying methods, vacuum microwave (VMD); freeze-drying (FD); and hot air (HAD), in Chilean abalone mollusk. Drying parameters, quality, energy consumption, and Sustainability parameters were evaluated. PEF+VMD showed better values than the other drying systems, with drying times 67% and 83% lower than PEF+FD and FD. In the quality parameters, PEF+FD showed a significantly lower value for hardness (250 N), and a lower change of color value (ΔE = 12). In the case of HAD, the PEF application did not significantly influence its processing. In energy parameters, VMD and PEF+VMD reduced energy consumption and CO2 emissions.Keywords: PEF technology, vacuum microwave drying, energy consumption, CO2 emissions
Procedia PDF Downloads 9110249 Fire Safety Engineering of Wood Dust Layer or Cloud
Authors: Marzena Półka, Bożena Kukfisz
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This paper presents an analysis of dust explosion hazards in the process industries. It includes selected testing method of dust explosibility and presentation two of them according to experimental standards used by Department of Combustion and Fire Theory in The Main School of Fire Service in Warsaw. In the article are presented values of maximum acceptable surface temperature (MAST) of machines operating in the presence of dust cloud and chosen dust layer with thickness of 5 and 12,5mm. The comparative analysis, points to the conclusion that the value of the minimum ignition temperature of the layer (MITL) and the minimum ignition temperature of dust cloud (MTCD) depends on the granularity of the substance. Increasing the thickness of the dust layer reduces minimum ignition temperature of dust layer. Increasing the thickness of dust at the same time extends the flameless combustion and delays the ignition.Keywords: fire safety engineering, industrial hazards, minimum ignition temperature, wood dust
Procedia PDF Downloads 31910248 Empowering Female Entrepreneurs for Economic Development: Challenges and Prospects within the Nigerian Economy
Authors: Inyene Nathaniel Nkanta
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The present economic situation in Nigeria, with an increase in inflation rate due to the fall of crude oil prices and post covid-19 crisis, has increased the level of poverty and suffering in Nigeria, particularly the women. Against that backdrop, this research project is initiated to explore ways to empower women through entrepreneurship education and training to ameliorate the poverty level amongst women in Nigeria. A qualitative approach to data collection will be applied in this study and to test the assertions of this research project empirically, this research adopts a case study research method as this will enable me to obtain and probe ways women can be empowered through semi-structured interviews and focus groups. The result of this research project will provide an original perspective on human capital development, most importantly, the need for entrepreneurial education and entrepreneurial literature and practice.Keywords: women, Nigeria, entrepreneurship education, Economic development, human capital
Procedia PDF Downloads 8510247 Tourism Climate Index Environmental Assessment of Piranshahr
Authors: Parvaneh Ziviar Pardehei, Esmaeil Hossinnejad
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In this research, the tourism climate index Miczcofski (TCI) and to assess climate Trjvng Piranshahr city tourism is discussed. The index is a systematic way to evaluate the climatic conditions for tourism. To calculate the parameters of mean monthly maximum temperature, minimum relative humidity, average daily relative humidity, rainfall, sunshine and the wind speed are used. In the months of April, July, August and September of comfort there in December, January, February and March, the nerve is cold comfort factor. Baker calculation method showed that during spring and summer cooling environment, mild, pleasant, and comfortable Byvklymay there. TCI results suggest that the months of April to July are top rated and best climatic conditions in terms of comfort to the tourists. In general, indices used in this paper show that the months of April to October is the best time for tourism in the city Piranshahr.Keywords: tourism, climate, Piranshahr city, TCI indicators and trjvng
Procedia PDF Downloads 26010246 Numerical Model to Study Calcium and Inositol 1,4,5-Trisphosphate Dynamics in a Myocyte Cell
Authors: Nisha Singh, Neeru Adlakha
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Calcium signalling is one of the most important intracellular signalling mechanisms. A lot of approaches and investigators have been made in the study of calcium signalling in various cells to understand its mechanisms over recent decades. However, most of existing investigators have mainly focussed on the study of calcium signalling in various cells without paying attention to the dependence of calcium signalling on other chemical ions like inositol-1; 4; 5 triphosphate ions, etc. Some models for the independent study of calcium signalling and inositol-1; 4; 5 triphosphate signalling in various cells are present but very little attention has been paid by the researchers to study the interdependence of these two signalling processes in a cell. In this paper, we propose a coupled mathematical model to understand the interdependence of inositol-1; 4; 5 triphosphate dynamics and calcium dynamics in a myocyte cell. Such studies will provide the deeper understanding of various factors involved in calcium signalling in myocytes, which may be of great use to biomedical scientists for various medical applications.Keywords: calcium signalling, coupling, finite difference method, inositol 1, 4, 5-triphosphate
Procedia PDF Downloads 29210245 A Novel Geometrical Approach toward the Mechanical Properties of Particle Reinforced Composites
Authors: Hamed Khezrzadeh
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Many investigations on the micromechanical structure of materials indicate that there exist fractal patterns at the micro scale in some of the main construction and industrial materials. A recently presented micro-fractal theory brings together the well-known periodic homogenization and the fractal geometry to construct an appropriate model for determination of the mechanical properties of particle reinforced composite materials. The proposed multi-step homogenization scheme considers the mechanical properties of different constituent phases in the composite together with the interaction between these phases throughout a step-by-step homogenization technique. In the proposed model the interaction of different phases is also investigated. By using this method the effect of fibers grading on the mechanical properties also could be studied. The theory outcomes are compared to the experimental data for different types of particle-reinforced composites which very good agreement with the experimental data is observed.Keywords: fractal geometry, homogenization, micromehcanics, particulate composites
Procedia PDF Downloads 29110244 Fabrication of Tin Oxide and Metal Doped Tin Oxide for Gas Sensor Application
Authors: Goban Kumar Panneer Selvam
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In past years, there is lots of death caused due to harmful gases. So its very important to monitor harmful gases for human safety, and semiconductor material play important role in producing effective gas sensors.A novel solvothermal synthesis method based on sol-gel processing was prepared to deposit tin oxide thin films on glass substrate at high temperature for gas sensing application. The structure and morphology of tin oxide were analyzed by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The SEM analysis of how spheres shape in tin oxide nanoparticles. The structure characterization of tin oxide studied by X-ray diffraction shows 8.95 nm (calculated by sheers equation). The UV visible spectroscopy indicated a maximum absorption band shown at 390 nm. Further dope tin oxide with selected metals to attain maximum sensitivity using dip coating technique with different immersion and sensing characterization are measured.Keywords: tin oxide, gas sensor, chlorine free, sensitivity, crystalline size
Procedia PDF Downloads 14610243 Static vs. Stream Mining Trajectories Similarity Measures
Authors: Musaab Riyadh, Norwati Mustapha, Dina Riyadh
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Trajectory similarity can be defined as the cost of transforming one trajectory into another based on certain similarity method. It is the core of numerous mining tasks such as clustering, classification, and indexing. Various approaches have been suggested to measure similarity based on the geometric and dynamic properties of trajectory, the overlapping between trajectory segments, and the confined area between entire trajectories. In this article, an evaluation of these approaches has been done based on computational cost, usage memory, accuracy, and the amount of data which is needed in advance to determine its suitability to stream mining applications. The evaluation results show that the stream mining applications support similarity methods which have low computational cost and memory, single scan on data, and free of mathematical complexity due to the high-speed generation of data.Keywords: global distance measure, local distance measure, semantic trajectory, spatial dimension, stream data mining
Procedia PDF Downloads 39610242 Mechanical Structural and Optical Properties of Lu₂SiO₅ Scintillator-Polymer Composite Films
Authors: M. S. E. Hamroun, K. Bachari, A. Berrayah, L. Mechernene, L. Guerbous
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Composite films containing homogeneously dispersed scintillation nano-particles of Lu₂SiO₅:Ce³⁺, in optically transparent polymer matrix, have been prepared and characterized through X-ray diffraction, differential scanning calorimetric (DSC), thermogravimetric analysis (ATG), dynamic mechanical analysis (DMA), electron scanning microscopy morphology (SEM) and photoluminescence (PL). Lu₂SiO₅:Ce³⁺ scintillator powder was successfully synthesized via Sol-Gel method. This study is realized with different mass ratios of nano-particles embedded in polystyrene and polylactic acid polymer matrix (5, 10, 15, 20%) to see the influence of nano-particles on the mechanical, structural and optical properties of films. The composites have been prepared with 400 µm thickness. It has found that the structural proprieties change with mass ratio on each sample. PL photoluminescence shows the characteristic Lu₂SiO₅:Ce³⁺ emission in the blue region and intensity varied for each film.Keywords: nano-particles, sol gel, photoluminescence, Ce³⁺, scintillator, polystyrene
Procedia PDF Downloads 12010241 Factors Affecting Consumers’ Willingness to Pay for Chicken Meat from Biosecure Farms
Authors: Veronica Sri Lestari, Asmuddin Natsir, Hasmida Karim, Ian Patrick
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The research aimed at investigating the factors affecting consumers’ willingness to pay for chicken meat from biosecure farms. The research was conducted in Makassar City, South Sulawesi Province, Indonesia. Samples were taken using random sampling technique in two supermarkets namely Lotte Mart and Gelael. Total samples were 50 respondents which comprised the chicken meat consumers. To find out the consumers’ willingness to pay for chicken meat from the biosecure farms, the contingent valuation method was utilized. Data were collected through interviews and questionnaires. Probit Logistic was estimated to examine the factors affecting the consumers’ willingness to pay for at the premium price for chicken meat from the biosecure farms. The research indicates that the education and income affect significantly the consumers’ willingness to pay for chicken meat from the biosecure farms (P < 0.05). The results of the study will be beneficial for the policy makers, producers, consumers and those conducting research.Keywords: biosecure, chicken, farms, consumer, willingness-to-pay
Procedia PDF Downloads 27410240 Biodiesel Production from Canola Oil Using Trans-Esterification Process with Koh as a Catalyst
Authors: M. Nafis Alfarizi, Dinda A. Utami, Arif Hidayat
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Biodiesel is one solution to overcome the use of petroleum fuels. Many alternative feedstocks that can be used among which canola oil. The purpose of this study was to determine the ability of canola oil and KOH for the trans-esterification reaction in biodiesel production. Canola oil has a very high purity that can be used as an alternative feedstock for biodiesel production and expected it will be produced biodiesel with excellent quality. In this case of study, we used trans-esterification process wherein the triglyceride is reacted with an alcohol with KOH as a catalyst, and it will produce biodiesel and glycerol as byproduct and we choose trans-esterification process because canola oil has a 0,445% FFA content. The variables studied in this research include the comparison of canola oil and methanol, temperature, time, and the percent of catalyst used. In this study the method of analysis we use GCMS and FTIR to know what the characteristic in canola oil. Development of canola oil seems to be the perfect solution to produce high-quality biodiesel. The reaction conditions resulted in 97.87% -w methyl ester (biodiesel) product by using a 0.5% wt KOH catalyst with canola and methanol ratio 1:8 at 60°C.Keywords: biodiesel, canola oil, KOH, trans-esterification
Procedia PDF Downloads 26410239 College Students’ Multitasking and Its Causes
Authors: Huey-Wen Chou, Shuo-Heng Liang
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This study focuses on studying college students’ multitasking with cellphones/laptops during lectures. In-class multitasking behavior is defined as the activities students engaged that are irrelevant to learning. This study aims to understand if students' learning engagement affects students' multitasking as well as to investigate the causes or motivations that contribute to the occurrence of multitasking behavior. Survey data were collected and analyzed by PLS method and multiple regression to test the research model and hypothesis. Major results include: 1. Students' multitasking motivation positively predicts students’ in-class multitasking. 2. Factors affecting multitasking in class, including efficiency, entertainment and social needs, significantly impact on multitasking. 3. Polychronic personality traits will positively predict students’ multitasking. 4. Students' classroom learning engagement negatively predicts multitasking. 5. Course attributes negatively predict student learning engagement and positively predict student multitasking.Keywords: engagement, monochronic personality, multitasking, learning, personality traits
Procedia PDF Downloads 13310238 Synthesis and Photophysical Studies of BOPIDY Dyes Conjugated with 4-Benzyloxystyryl Substituents
Authors: Bokolombe Pitchou Ngoy, John Mack, Tebello Nyokong
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Synthesis and photochemical studies of BODIPY dyes have been investigated in this work in order to have a broad benchmark of this functionalized photosensitizer for biological applications such as photodynamic therapy or antimicrobial activity. The common acid catalyzed synthetic method was used, and BODIPY dyes were obtained in quite a good yield (25 %) followed by bromination and Knoevenagel condensation to afford the BODIPY dyes conjugated with maximum absorbance in the near-infrared region of the electromagnetic spectrum. The fluorescence lifetimes, fluorescence quantum yield, and Singlet oxygen quantum yield of the conjugated BODIPY dyes were determined in different solvents by using Time Correlation Single Photon Counting (TCSPC), fluorimeter, and Laser Flash Photolysis respectively. It was clearly shown that the singlet oxygen quantum yield was higher in THF followed by DMSO compared to another solvent. The same trend was observed for the fluorescence lifetimes.Keywords: BODIPY, photodynamic therapy, photosensitizer, singlet oxygen
Procedia PDF Downloads 30010237 Performances Analysis of the Pressure and Production of an Oil Zone by Simulation of the Flow of a Fluid through the Porous Media
Authors: Makhlouf Mourad, Medkour Mihoub, Bouchher Omar, Messabih Sidi Mohamed, Benrachedi Khaled
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This work is the modeling and simulation of fluid flow (liquid) through porous media. This type of flow occurs in many situations of interest in applied sciences and engineering, fluid (oil) consists of several individual substances in pure, single-phase flow is incompressible and isothermal. The porous medium is isotropic, homogeneous optionally, with the rectangular format and the flow is two-dimensional. Modeling of hydrodynamic phenomena incorporates Darcy's law and the equation of mass conservation. Correlations are used to model the density and viscosity of the fluid. A finite volume code is used in the discretization of differential equations. The nonlinearity is treated by Newton's method with relaxation coefficient. The results of the simulation of the pressure and the mobility of liquid flowing through porous media are presented, analyzed, and illustrated.Keywords: Darcy equation, middle porous, continuity equation, Peng Robinson equation, mobility
Procedia PDF Downloads 21810236 The Effect of Material Properties and Volumetric Changes in Phase Transformation to the Final Residual Stress of Welding Process
Authors: Djarot B. Darmadi
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The wider growing Finite Element Method (FEM) application is caused by its benefits of cost saving and environment friendly. Also, by using FEM a deep understanding of certain phenomenon can be achieved. This paper observed the role of material properties and volumetric change when Solid State Phase Transformation (SSPT) takes place in residual stress formation due to a welding process of ferritic steels through coupled Thermo-Metallurgy-Mechanical (TMM) analysis. The correctness of FEM residual stress prediction was validated by experiment. From parametric study of the FEM model, it can be concluded that the material properties change tend to over-predicts residual stress in the weld center whilst volumetric change tend to underestimates it. The best final result is the compromise of both by incorporates them in the model which has a better result compared to a model without SSPT.Keywords: residual stress, ferritic steels, SSPT, coupled-TMM
Procedia PDF Downloads 27010235 Numerical Investigation of Pressure and Velocity Field Contours of Dynamics of Drop Formation
Authors: Pardeep Bishnoi, Mayank Srivastava, Mrityunjay Kumar Sinha
Abstract:
This article represents the numerical investigation of the pressure and velocity field variation of the dynamics of pendant drop formation through a capillary tube. Numerical simulations are executed using volume of fluid (VOF) method in the computational fluid dynamics (CFD). In this problem, Non Newtonian fluid is considered as dispersed fluid whereas air is considered as a continuous fluid. Pressure contours at various time steps expose that pressure varies nearly hydrostatically at each step of the dynamics of drop formation. A result also shows the pressure variation of the liquid droplet during free fall in the computational domain. The evacuation of the fluid from the necking region is also shown by the contour of the velocity field. The role of surface tension in the Pressure contour of the dynamics of drop formation is also studied.Keywords: pressure contour, surface tension, volume of fluid, velocity field
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