Search results for: three-dimensional video microscope
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1736

Search results for: three-dimensional video microscope

566 Enabling UDP Multicast in Cloud IaaS: An Enterprise Use Case

Authors: Patrick J. Kerpan, Ryan C. Koop, Margaret M. Walker, Chris P. Swan

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The User Datagram Protocol (UDP) multicast is a vital part of data center networking that is being left out of major cloud computing providers' network infrastructure. Enterprise users rely on multicast, and particularly UDP multicast to create and connect vital business operations. For example, UPD makes a variety of business functions possible from simultaneous content media updates, High-Performance Computing (HPC) grids, and video call routing for massive open online courses (MOOCs). Essentially, UDP multicast's technological slight is causing a huge effect on whether companies choose to use (or not to use) public cloud infrastructure as a service (IaaS). Allowing the ‘chatty’ UDP multicast protocol inside a cloud network could have a serious impact on the performance of the cloud as a whole. Cloud IaaS providers solve the issue by disallowing all UDP multicast. But what about enterprise use cases for multicast applications in organizations that want to move to the cloud? To re-allow multicast traffic, enterprises can build a layer 3 - 7 network over the top of a data center, private cloud, or public cloud. An overlay network simply creates a private, sealed network on top of the existing network. Overlays give complete control of the network back to enterprise cloud users the freedom to manage their network beyond the control of the cloud provider’s firewall conditions. The same logic applies if for users who wish to use IPsec or BGP network protocols inside or connected into an overlay network in cloud IaaS.

Keywords: cloud computing, protocols, UDP multicast, virtualization

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565 Studying the Effect of Different Sizes of Carbon Fiber on Locally Developed Copper Based Composites

Authors: Tahir Ahmad, Abubaker Khan, Muhammad Kamran, Muhammad Umer Manzoor, Muhammad Taqi Zahid Butt

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Metal Matrix Composites (MMC) is a class of weight efficient structural materials that are becoming popular in engineering applications especially in electronic, aerospace, aircraft, packaging and various other industries. This study focuses on the development of carbon fiber reinforced copper matrix composite. Keeping in view the vast applications of metal matrix composites,this specific material is produced for its unique mechanical and thermal properties i.e. high thermal conductivity and low coefficient of thermal expansion at elevated temperatures. The carbon fibers were not pretreated but coated with copper by electroless plating in order to increase the wettability of carbon fiber with the copper matrix. Casting is chosen as the manufacturing route for the C-Cu composite. Four different compositions of the composite were developed by varying the amount of carbon fibers by 0.5, 1, 1.5 and 2 wt. % of the copper. The effect of varying carbon fiber content and sizes on the mechanical properties of the C-Cu composite is studied in this work. The tensile test was performed on the tensile specimens. The yield strength decreases with increasing fiber content while the ultimate tensile strength increases with increasing fiber content. Rockwell hardness test was also performed and the result followed the increasing trend for increasing carbon fibers and the hardness numbers are 30.2, 37.2, 39.9 and 42.5 for sample 1, 2, 3 and 4 respectively. The microstructures of the specimens were also examined under the optical microscope. Wear test and SEM also done for checking characteristic of C-Cu marix composite. Through casting may be a route for the production of the C-Cu matrix composite but still powder metallurgy is better to follow as the wettability of carbon fiber with matrix, in that case, would be better.

Keywords: copper based composites, mechanical properties, wear properties, microstructure

Procedia PDF Downloads 345
564 In vitro Antioxidant and Antisickling Effects of Aerva javanica, and Ficus palmata Extracts on Sickle Cell Anemia

Authors: E. A. Alaswad, H. M. Choudhry, F. Z. Filimban

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Sickle Cell Anemia (SCA) is one type of blood diseases related to autosomal disorder. The sickle shaped red blood cells are the main cause of many problems in the blood vessels and capillaries. Aerva Javanica (J) and Ficus Palmata (P) are medicinal plants that have many popular uses and have been proved their efficacy. The aim of this study was to assess the antioxidants activity and the antisickling effect of J and P extractions. The period of this study, air-dried leaves of J, and P plants were ground and the active components were extracted by maceration in water (W) and methanol (M) as solvents. The antioxidants activity of JW, PW, JM, and PM were assessed by way of the radical scavenging method using 2,2-diphenyl-1-picrylhydrazyl (DPPH). To determine the antisickling effect of J and P extracts. 20 samples were collected from sickle cell anemia patients. Different concentrations of J and P extracts (200 and 110 μg/mL) were added on the sample and incubated. A drop of each sample was examined with light microscope. Normal and sickled RBCs were calculated and expressed as the percent of sickling. The stabilization effect of the extracts was measured by the osmotic fragility test for erythrocytes. The finding suggests as estimated by DPPH method, all the extracts showed an antioxidant activity with a significant inhibition of the DPPH radicals. PM has the least IC50% with 71.49 μg/ml while JM was the most with 408.49 μg/ml. Sickle cells treated with extracts at different concentrations significantly reduced the percentage of sickling compering to control samples. However, JM 200 μg/mL give the highest anti-sickling affect with 17.4% of sickling compared to control 67.5 of sickling while PM at 200 μg/mL showed the highest membrane cell stability. In a conclusion, the results showed that J and P extracts have antisickling effects. Therefore, the Aerva javanica and Ficus palmata may have a role in SCA management and a good impact on the patient's lives.

Keywords: Aerva javanica, antioxidant, antisickling, Ficus palmata, sickle cell anemia

Procedia PDF Downloads 143
563 Design of Low-Cost Water Purification System Using Activated Carbon

Authors: Nayan Kishore Giri, Ramakar Jha

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Water is a major element for the life of all the mankind in the earth. India’s surface water flows through fourteen major streams. Indian rivers are the main source of potable water in India. In the eastern part of India many toxic hazardous metals discharged into the river from mining industries, which leads many deadly diseases to human being. So the potable water quality is very significant and vital concern at present as it is related with the present and future health perspective of the human race. Consciousness of health risks linked with unsafe water is still very low among the many rural and urban areas in India. Only about 7% of total Indian people using water purifier. This unhealthy situation of water is not only present in India but also present in many underdeveloped countries. The major reason behind this is the high cost of water purifier. This current study geared towards development of economical and efficient technology for the removal of maximum possible toxic metals and pathogen bacteria. The work involves the design of portable purification system and purifying material. In this design Coconut shell granular activated carbon(GAC) and polypropylene filter cloths were used in this system. The activated carbon is impregnated with Iron(Fe). Iron is used because it enhances the adsorption capacity of activated carbon. The thorough analysis of iron impregnated activated carbon(Fe-AC) is done by Scanning Electron Microscope (SEM), X-ray diffraction (XRD) , BET surface area test were done. Then 10 ppm of each toxic metal were infiltrated through the designed purification system and they were analysed in Atomic absorption spectrum (AAS). The results are very promising and it is low cost. This work will help many people who are in need of potable water. They can be benefited for its affordability. It could be helpful in industries and other domestic usage.

Keywords: potable water, coconut shell GAC, polypropylene filter cloths, SEM, XRD, BET, AAS

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562 Aggregation-Induced-Active Stimuli-Responsive Based Nano-Objects for Wastewater Treatment Application

Authors: Parvaneh Eskandari, Rachel O'Reilly

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In the last years, controlling the self-assembly behavior of stimuli-responsive nano-objects, including micelles, vesicles, worm-like, etc., at different conditions is considered a pertinent challenge in the polymer community. The aim of the project was to synthesize aggregation-induced emission (AIE)-active stimuli-responsive polymeric nano-objects to control the self-assemblies morphologies of the prepared nano-objects. Two types of nanoobjects, micelle and vesicles, including PDMAEMA-b-P(BzMA-TPEMA) [PDMAEMA: poly(N,Ndimethylaminoethyl methacrylate); P(BzMA-TPEMA): poly[benzyl methacrylate-co- tetraphenylethene methacrylate]] were synthesized by using reversible addition−fragmentation chain-transfer (RAFT)- mediated polymerization-induced self-assembly (PISA), which combines polymerization and self-assembly in a single step. Transmission electron microscope and dynamic light scattering (DLS) analysis were used to confirm the formed self-assemblies morphologies. The controlled self-assemblies were applied as nitrophenolic compounds (NPCs) adsorbents from wastewater, thanks to their CO2-responsive part, PDMAEMA. Moreover, the fluorescence-active part of the prepared nano-objects, P(BzMA-TPEMA), played a key role in the detection of the NPCs at the aqueous solution. The optical properties of the prepared nano-objects were studied by UV/Vis and fluorescence spectroscopies. For responsivity investigations, the hydrodynamic diameter and Zeta-potential (ζ-potential) of the sample's aqueous solution were measured by DLS. In the end, the prepared nano-objects were used for the detection and adsorption of different NPCs.

Keywords: aggregation-induced emission polymers, stimuli-responsive polymers, reversible addition−fragmentation chain-transfer polymerization, polymerization-induced self-assembly, wastewater treatment

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561 Real-Time Pedestrian Detection Method Based on Improved YOLOv3

Authors: Jingting Luo, Yong Wang, Ying Wang

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Pedestrian detection in image or video data is a very important and challenging task in security surveillance. The difficulty of this task is to locate and detect pedestrians of different scales in complex scenes accurately. To solve these problems, a deep neural network (RT-YOLOv3) is proposed to realize real-time pedestrian detection at different scales in security monitoring. RT-YOLOv3 improves the traditional YOLOv3 algorithm. Firstly, the deep residual network is added to extract vehicle features. Then six convolutional neural networks with different scales are designed and fused with the corresponding scale feature maps in the residual network to form the final feature pyramid to perform pedestrian detection tasks. This method can better characterize pedestrians. In order to further improve the accuracy and generalization ability of the model, a hybrid pedestrian data set training method is used to extract pedestrian data from the VOC data set and train with the INRIA pedestrian data set. Experiments show that the proposed RT-YOLOv3 method achieves 93.57% accuracy of mAP (mean average precision) and 46.52f/s (number of frames per second). In terms of accuracy, RT-YOLOv3 performs better than Fast R-CNN, Faster R-CNN, YOLO, SSD, YOLOv2, and YOLOv3. This method reduces the missed detection rate and false detection rate, improves the positioning accuracy, and meets the requirements of real-time detection of pedestrian objects.

Keywords: pedestrian detection, feature detection, convolutional neural network, real-time detection, YOLOv3

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560 SIM (Subscriber Identity Module) Banking

Authors: Okanta Andrew, Richmond Kweku Frempong

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As mobile networks are upgraded with technologies like WAP, GPRS and UMTS to deliver next-generation multimedia services, so are the banks and other financial institutions also getting ready to unleash the financial products on the mobile platform to meet growing demand for mobile based application services. Hence, the onset of Unstructured Supplementary Services (USSD) Banking which would make banking services available at anywhere, anytime through a string of interactive SMS sessions between a mobile device and an application server of a service provider. The aim of this studies was to find out whether the public will accept the sim banking service when it is implemented. Our target group includes: Working class. E. g. Businessmen/women, office workers, fishermen, market women, teachers etc. Nonworking class. E. g. Students (Tertiary, Senior High School), housewives. etc. The survey was in the form of a questionnaire and a verbal interview (video) which was to investigate their idea about the current banking system and the yet to be introduced sim banking concept. Meanwhile, some challenges accompanied the progression of data gathering because some populace showed reluctance in freeing their information. One other suggestion was that government should put measures against foremost challenges obstructing sim banking in Ghana counter to computers hackers. Government and individual have a key role to undertake to give suitable support to facelift the sim banking industry in the country. It was also suggested that Government put strong regulations on the use of sim banking products and services to streamline all the activities and also create awareness of the need for sim banking and emphasize its relevance in the aspect of national GDP.

Keywords: banking, mobile banking, SIM banking, mobile banking in Ghana

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559 The Effect of Mixing and Degassing Conditions on the Properties of Epoxy/Anhydride Resin System

Authors: Latha Krishnan, Andrew Cobley

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Epoxy resin is most widely used as matrices for composites of aerospace, automotive and electronic applications due to its outstanding mechanical properties. These properties are chiefly predetermined by the chemical structure of the prepolymer and type of hardener but can also be varied by the processing conditions such as prepolymer and hardener mixing, degassing and curing conditions. In this research, the effect of degassing on the curing behaviour and the void occurrence is experimentally evaluated for epoxy /anhydride resin system. The epoxy prepolymer was mixed with an anhydride hardener and accelerator in an appropriate quantity. In order to investigate the effect of degassing on the curing behaviour and void content of the resin, the uncured resin samples were prepared using three different methods: 1) no degassing 2) degassing on prepolymer and 3) degassing on mixed solution of prepolymer and hardener with an accelerator. The uncured resins were tested in differential scanning calorimeter (DSC) to observe the changes in curing behaviour of the above three resin samples by analysing factors such as gel temperature, peak cure temperature and heat of reaction/heat flow in curing. Additionally, the completely cured samples were tested in DSC to identify the changes in the glass transition temperature (Tg) between the three samples. In order to evaluate the effect of degassing on the void content and morphology changes in the cured epoxy resin, the fractured surfaces of cured epoxy resin were examined under the scanning electron microscope (SEM). Also, the changes in the mechanical properties of the cured resin were studied by three-point bending test. It was found that degassing at different stages of resin mixing had significant effects on properties such as glass transition temperature, the void content and void size of the epoxy/anhydride resin system. For example, degassing (vacuum applied on the mixed resin) has shown higher glass transition temperature (Tg) with lower void content.

Keywords: anhydride epoxy, curing behaviour, degassing, void occurrence

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558 Famotidine Loaded Solid Lipid Nanoparticles (SLN) for Oral Delivery System

Authors: Rachmat Mauludin, Novita R. Kusuma, Diky Mudhakir

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Famotidine (FMT) is one of used substances in the treatment of hiperacidity and peptic ulcer, administered orally and parenterally via intravenous injection. Oral administration, which is more favorable, has been reported to have many obstacles in the process of the treatment, includes decreasing the bioavailability of FMT. This research was aimed to prepare FMT in form of solid lipid nanoparticles (SLN) with size ranging between 100-200 nm. The research was carried out also by optimizing factors that may affect physical stability of SLN. Formulation of Famotidine SLN was carried out by optimizing factors, such as duration of homogenization and sonication, lipid concentration, stabilizer composition and stabilizer concentration. SLN physical stability was evaluated (particle size distribution) for 42 days in 3 diferent temperatures. Entrapment efficiency and drug loading was determined indirectly and directly. The morphology of SLN was visualized by transmission electron microscope (TEM). In vitro release study of FMT was conducted in 2 mediums, at pH of 1.2 and 7.4. Chemical stability of FMT was determined by quantifying the concentration of FMT within 42 days. Famotidin SLN consisted of GMS as lipid and poloxamer 188, lecithin, and polysorbate 80 as stabilizers. Homogenization and sonication was performed for 5 minutes and 10 minutes. Physyical stability of nanoparticles at 3 different temperatures was no significant difference. The best formula was physically stable until 42 days with mean particle size below 200 nm. Nanoparticles produced was able to entrap FMT until 86.6%. Evaluation by TEM showed that nanoparticles was spherical and solid. In medium pH of 1.2, FMT was released only 30% during 4 hour. On the other hand, within 4 hours SLN could release FMT completely in medium pH of 7.4. The FMT concentration in nanoparticles dispersion was maintained until 95% in 42 days (40oC, RH 75%). Famotidine SLN was able to be produced with mean particle size ranging between 100-200 nm and physically stable for 42 days. SLN could be loaded by 86,6% of FMT. Morphologically, obtained SLN was spheric and solid. During 4 hours in medium pH of 1.2 and 7.4, FMT was released until 30% and 100%, respectively.

Keywords: solid lipid nanoparticle (SLN), famotidine (FMT), physicochemical properties, release study

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557 Role of Microplastics on Reducing Heavy Metal Pollution from Wastewater

Authors: Derin Ureten

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Plastic pollution does not disappear, it gets smaller and smaller through photolysis which are caused mainly by sun’s radiation, thermal oxidation, thermal degradation, and biodegradation which is the action of organisms digesting larger plastics. All plastic pollutants have exceedingly harmful effects on the environment. Together with the COVID-19 pandemic, the number of plastic products such as masks and gloves flowing into the environment has increased more than ever. However, microplastics are not the only pollutants in water, one of the most tenacious and toxic pollutants are heavy metals. Heavy metal solutions are also capable of causing varieties of health problems in organisms such as cancer, organ damage, nervous system damage, and even death. The aim of this research is to prove that microplastics can be used in wastewater treatment systems by proving that they could adsorb heavy metals in solutions. Experiment for this research will include two heavy metal solutions; one including microplastics in a heavy metal contaminated water solution, and one that just includes heavy metal solution. After being sieved, absorbance of both mediums will be measured with the help of a spectrometer. Iron (III) chloride (FeCl3) will be used as the heavy metal solution since the solution becomes darker as the presence of this substance increases. The experiment will be supported by Pure Nile Red powder in order to observe if there are any visible differences under the microscope. Pure Nile Red powder is a chemical that binds to hydrophobic materials such as plastics and lipids. If proof of adsorbance could be observed by the rates of the solutions' final absorbance rates and visuals ensured by the Pure Nile Red powder, the experiment will be conducted with different temperature levels in order to analyze the most accurate temperature level to proceed with removal of heavy metals from water. New wastewater treatment systems could be generated with the help of microplastics, for water contaminated with heavy metals.

Keywords: microplastics, heavy metal, pollution, adsorbance, wastewater treatment

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556 The Axonal Connectivity of Motor and Premotor Areas as Revealed through Fiber Dissections: Shedding Light on the Structural Correlates of Complex Motor Behavior

Authors: Spyridon Komaitis, Christos Koutsarnakis, Evangelos Drosos, Aristotelis Kalyvas

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This study opts to investigate the intrinsic architecture, morphology, and spatial relationship of the subcortical pathways implicated in the connectivity of the motor/premotor cortex and SMA/pre-SMA complex. Twenty normal, adult, formalin-fixed cerebral hemispheres were explored through the fiber micro-dissection technique. Lateral to medial and medial to lateral dissections focused on the area of interest were performed in a tandem manner and under the surgical microscope. We traced the subcortical architecture, spatial relationships, and axonal connectivity of four major pathways: a) the dorsal component of the SLF (SLF-I) was found to reside in the medial aspect of the hemisphere and seen to connect the precuneus with the SMA and pre-SMA complex, b) the frontal longitudinal system (FLS) was consistently encountered as the natural anterior continuation of the SLF-II and SLF-III and connected the premotor and prefrontal cortices c) the fronto-caudate tract (FCT), a fan-shaped tract, was documented to participate in connectivity of the prefrontal and premotor cortices to the head and body of the caudate nucleus and d) the cortico-tegmental tract(CTT) was invariably recorded to subserve the connectivity of the tegmental area with the fronto-parietal cortex. No hemispheric asymmetries were recorded for any of the implicated pathways. Sub-segmentation systems were also proposed for each of the aforementioned tracts. The structural connectivity and functional specialization of motor and premotor areas in the human brain remain vague to this day as most of the available evidence derives either from animal or tractographic studies. By using the fiber-microdissection technique as our main method of investigation, we provide sound structural evidence on the delicate anatomy of the related white matter pathways.

Keywords: neuroanatomy, premotor, motor, connectivity

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555 Quantifying Late Cenozoic Out‐of‐Sequence Thrusting at Chaura, Sutlej Valley, Himachal Pradesh, India

Authors: Rajkumar Ghosh

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Out-of-sequence thrusts (OOST) are reported at different geographic locations with various local names along Siwalik Himalaya (SH), Lesser Himalaya (LH), Higher Himalaya (HH) from Bhutan, India, Nepal, and Pakistan Himalayan range. Most of OOSTs have been identified within the upper LH, and the lower HH based on geochronological age jump across. These thrusts activated from Late Miocene to recent. The Chaura Thrust (CT) was deciphered from age jump of Apatite Fission Track (AFT) and considered as blind thrust base on variable exhumation rates in Chaura region, Satluj river valley, Himachal Pradesh. CT is located north of Jhakri Thrust (JhT) and is also differently identified as Sarahan thrust (ST). Structural documentation from the rocks near the OOST in Chaura was not so far done. Detail structural study of the Jeori Group of rocks was carried out in this study to understand the manifestation of the Chaura thrust and associated structures in meso- to micro-scale. Box fold, scar fold, kink fold, crenulation cleavages, and boudins are developed in the Chaura region. These structures usually do not indicate shear sense. When studied under an optical microscope, the Chaura samples reveal that the mica fish are usually lenticular with aspect ratio (R) varying from 6–11 and inclination angle (α) from 15–40°. According to ‘R’ and ‘α’, elongated sigmoid shaped mica fish and parallelogram shaped mica fish were also documented. Asymmetric mica fish demonstrate top-to-S/SW ductile shear, which is similar as that of Chaura thrust. Grain boundary migration (GBM) structures in quartzo-feldspathic grains from Jeori Group of rocks indicate deformation temperature ranging from 400 to 650°C. This can indicate that the OOST at Chaura, i.e., the Chaura Thrust, underwent thrusting in the ductile regime.

Keywords: out-of-sequence thrust, chaura thrust, sarahan thrust, jakhri thrust, higher himalaya, s/c- fabric

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554 Color-Based Emotion Regulation Model: An Affective E-Learning Environment

Authors: Sabahat Nadeem, Farman Ali Khan

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Emotions are considered as a vital factor affecting the process of information handling, level of attention, memory capacity and decision making. Latest e-Learning systems are therefore taking into consideration the effective state of learners to make the learning process more effective and enjoyable. One such use of user’s affective information is in the systems that tend to regulate users’ emotions to a state optimally desirable for learning. So for, this objective has been tried to be achieved with the help of teaching strategies, background music, guided imagery, video clips and odors. Nevertheless, we know that colors can affect human emotions. Relationship between color and emotions has a strong influence on how we perceive our environment. Similarly, the colors of the interface can also affect the user positively as well as negatively. This affective behavior of color and its use as emotion regulation agent is not yet exploited. Therefore, this research proposes a Color-based Emotion Regulation Model (CERM), a new framework that can automatically adapt its colors according to user’s emotional state and her personality type and can help in producing a desirable emotional effect, aiming at providing an unobtrusive emotional support to the users of e-learning environment. The evaluation of CERM is carried out by comparing it with classical non-adaptive, static colored learning management system. Results indicate that colors of the interface, when carefully selected has significant positive impact on learner’s emotions.

Keywords: effective learning, e-learning, emotion regulation, emotional design

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553 Automatic Detection and Update of Region of Interest in Vehicular Traffic Surveillance Videos

Authors: Naydelis Brito Suárez, Deni Librado Torres Román, Fernando Hermosillo Reynoso

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Automatic detection and generation of a dynamic ROI (Region of Interest) in vehicle traffic surveillance videos based on a static camera in Intelligent Transportation Systems is challenging for computer vision-based systems. The dynamic ROI, being a changing ROI, should capture any other moving object located outside of a static ROI. In this work, the video is represented by a Tensor model composed of a Background and a Foreground Tensor, which contains all moving vehicles or objects. The values of each pixel over a time interval are represented by time series, and some pixel rows were selected. This paper proposes a pixel entropy-based algorithm for automatic detection and generation of a dynamic ROI in traffic videos under the assumption of two types of theoretical pixel entropy behaviors: (1) a pixel located at the road shows a high entropy value due to disturbances in this zone by vehicle traffic, (2) a pixel located outside the road shows a relatively low entropy value. To study the statistical behavior of the selected pixels, detecting the entropy changes and consequently moving objects, Shannon, Tsallis, and Approximate entropies were employed. Although Tsallis entropy achieved very high results in real-time, Approximate entropy showed results slightly better but in greater time.

Keywords: convex hull, dynamic ROI detection, pixel entropy, time series, moving objects

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552 Evaluation of Chitin Filled Epoxy Coating for Corrosion Protection of Q235 Steel in Saline Environment

Authors: Innocent O. Arukalam, Emeka E. Oguzie

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Interest in the development of eco-friendly anti-corrosion coatings using bio-based renewable materials is gaining momentum recently. To this effect, chitin biopolymer, which is non-toxic, biodegradable, and inherently possesses anti-microbial property, was successfully synthesized from snail shells and used as a filler in the preparation of epoxy coating. The chitin particles were characterized with contact angle goniometer, scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectrophotometer, and X-ray diffractometer (XRD). The performance of the coatings was evaluated by immersion and electrochemical impedance spectroscopy (EIS) tests. Electronic structure properties of the coating ingredients and molecular level interaction of the corrodent and coated Q235 steel were appraised by quantum chemical computations (QCC) and molecular dynamics (MD) simulation techniques, respectively. The water contact angle (WCA) measurement of chitin particles was found to be 129.3o while that of chitin particles modified with amino trimethoxy silane (ATMS) was 149.6o, suggesting it is highly hydrophobic. Immersion and EIS analyses revealed that epoxy coating containing silane-modified chitin exhibited lowest water absorption and highest barrier as well as anti-corrosion performances. The QCC showed that quantum parameters for the coating containing silane-modified chitin are optimum and therefore corresponds to high corrosion protection. The high negative value of adsorption energies (Eads) for the coating containing silane-modified chitin indicates the coating molecules interacted and adsorbed strongly on the steel surface. The observed results have shown that silane-modified epoxy-chitin coating would perform satisfactorily for surface protection of metal structures in saline environment.

Keywords: chitin, EIS, epoxy coating, hydrophobic, molecular dynamics simulation, quantum chemical computation

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551 Synthesis of Na-LSX Zeolite and Hydrosodalite from Polish Fly Ashes

Authors: Barbara Bialecka, Zdzislaw Adamczyk, Magdalena Cempa

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In the work, the results of investigations into the hydrothermal zeolitization of fly ash from hard coal combustion in one of Polish Power Station have been presented. The chemical composition of the ash was determined by the method of X-ray fluorescence (XRF), whereas the phases of both fly ash and the products after synthesis were identified using microscopic observations, X-ray diffraction analysis (XRD) as well as electron scanning microscopy with measurements of the chemical compositions in micro areas (SEM/EDS). The synthesis was carried out with various concentrations of NaOH solution (3M, 4M and 6M) in the following conditions: synthesis temperature – 80ᵒC, synthesis time – 16 hours, volume of NaOH solution – 350ml, fly ash mass – 14g. The main chemical components of fly ash were SiO₂ and Al₂O₃, the contents of which reached 51.62 and 28.14%mas., respectively. The input ash contained mainly such phases as mullite, quarz, magnetite, and glass. The research results indicate that the phase composition of products after zeolitization was differentiated. The material after synthesis in 3M NaOH solution was found to contain mullite, quarz, magnetite, and Na-LSX zeolite. The products of synthesis in 4M NaOH solution were very similar to those in 3M solution (mullite, quarz, magnetite, Na-LSX zeolite), but they additionally contained hydrosodalite. The material after synthesis in 6M NaOH solution contains mullite, quarz, magnetite (similarly to synthesis in 3M and 4M NaOH solition) and additionally hydrosodalite. Therefore, the products of synthesis contain relic components from the fly ash input sample in the form of mullite, quarz, and magnetite, as well as new phases, which are Na-LSX zeolite and hydrosodalite. It should be noted that the products of synthesis in the case of 4M NaOH solution contained both new phases (Na-LSX zeolite and hydrosodalite), while the products from the extreme concentration of NaOH solutions (3M and 6M) contained only one of them. Observations in the scanning electron microscope revealed the new phases’ morphology. It was found that Na-LSX zeolite formed cubic crystals, whereas hydrosodalite formed characteristic aggregations. The results of investigations into the chemical composition in the micro area of phase grains in the products after synthesis reveal some dependencies, among others a characteristic increase in the content of sodium, related to the increased concentration of NaOH solution.

Keywords: Na-LSX, fly ash, hydrosodalite, zeolite

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550 Using Recycled Wastes (Glass Powder) as Partially Replacement for Cement

Authors: Passant Youssef, Ahmed El-Tair, Amr El-Nemr

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Lately, with the environmental changes, enthusiasts trigger to stop the contamination of environment. Thus, various efforts were exerted for innovating environmental friendly concrete to sustain as a ‘Green Building’ material. Green building materials consider the cement industry as one of the most sources of air pollutant with high rate of carbon dioxide (CO₂) emissions. Several methods were developed to extensively reduce the influence of cement industry on environment. These methods such as using supplementary cementitious material or improving the cement manufacturing process are still under investigation. However, with the presence of recycled wastes from construction and finishing materials, the use of supplementary cementitious materials seems to provide an economic solution. Furthermore, it improves the mechanical properties of cement paste, in addition to; it modulates the workability and durability of concrete. In this paper, the glass powder was considered to be used as partial replacement of cement. This study provided the mechanical influence for using the glass powder as partial replacement of cement. In addition, it examines the microstructure of cement mortar using scanning electron microscope and X-ray diffraction. The cement in concrete is replaced by waste glass powder in steps of 5%, 10%, 15%, 20% and 25% by weight of cement and its effects on compressive and flexure strength were determined after 7 and 28 days. It was found that the 5% glass powder replacement increased the 7 days compressive strength by 20.5%, however, there was no increase in compressive strength after 28 days; which means that the glass powder did not react in the cement mortar due to its amorphous nature on the long run, and it can act as fine aggregate better that cement replacement. As well as, the 5% and 10% glass powder replacement increased the 28 days flexural strength by 46.9%. SEM micrographs showed very dense matrix for the optimum specimen compared to control specimen as well; some glass particles were clearly observed. High counts of silica were optimized from XRD while amorphous materials such as calcium silicate cannot be directly detected.

Keywords: supplementary materials, glass powder, concrete, cementitious materials

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549 Spherical Organic Particle (SOP) Emissions from Fixed-Bed Residential Coal-Burning Devices

Authors: Tafadzwa Makonese, Harold Annegarn, Patricia Forbes

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Residential coal combustion is one of the largest sources of carbonaceous aerosols in the Highveld region of South Africa, significantly affecting the local and regional climate. In this study, we investigated single coal burning particles emitted when using different fire-ignition techniques (top-lit up-draft vs bottom-lit up-draft) and air ventilation rates (defined by the number of air holes above and below the fire grate) in selected informal braziers. Aerosol samples were collected on nucleopore filters at the SeTAR Centre Laboratory, University of Johannesburg. Individual particles (~700) were investigated using a scanning electron microscope equipped with an energy-dispersive X-ray spectroscopy (EDS). Two distinct forms of spherical organic particles (SOPs) were identified, one less oxidized than the other. The particles were further classified into "electronically" dark and bright, according to China et al. [2014]. EDS analysis showed that 70% of the dark spherical organic particles balls had higher (~60%) relative oxygen content than in the bright SOPs. We quantify the morphology of spherical organic particles and classify them into four categories: ~50% are bare single particles; ~35% particles are aggregated and form diffusion accretion chains; 10% have inclusions; and 5% are deformed due to impaction on filter material during sampling. We conclude that there are two distinct kinds of coal burning spherical organic particles and that dark SOPs are less volatile than bright SOPs. We also show that these spherical organic particles are similar in nature and characteristics to tar balls observed in biomass combustion, and that they have the potential to absorb sunlight thereby affecting the earth’s radiative budget and climate. This study provides insights on the mixing states, morphology, and possible formation mechanisms of these organic particles from residential coal combustion in informal stoves.

Keywords: spherical organic particles, residential coal combustion, fixed-bed, aerosols, morphology, stoves

Procedia PDF Downloads 453
548 Boron Nitride Nanoparticle Enhanced Prepreg Composite Laminates

Authors: Qiong Tian, Lifeng Zhang, Demei Yu, Ajit D. Kelkar

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Low specific weight and high strength is the basic requirement for aerospace materials. Fiber-reinforced epoxy resin composites are attractive materials for this purpose. Boron nitride nanoparticles (BNNPs) have good radiation shielding capacity, which is very important to aerospace materials. Herein a processing route for an advanced hybrid composite material is demonstrated by introducing dispersed BNNPs in standard prepreg manufacturing. The hybrid materials contain three parts: E-fiberglass, an aerospace-grade epoxy resin system, and BNNPs. A vacuum assisted resin transfer molding (VARTM) was utilized in this processing. Two BNNP functionalization approaches are presented in this study: (a) covalent functionalization with 3-aminopropyltriethoxysilane (KH-550); (b) non-covalent functionalization with cetyltrimethylammonium bromide (CTAB). The functionalized BNNPs were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction(XRD) and scanning electron microscope (SEM). The results showed that BN powder was successfully functionalized via the covalent and non-covalent approaches without any crystal structure change and big agglomerate particles were broken into platelet-like nanoparticles (BNNPs) after functionalization. Compared to pristine BN powder, surface modified BNNPs could result in significant improvement in mechanical properties such as tensile, flexural and compressive strength and modulus. CTAB functionalized BNNPs (CTAB-BNNPs) showed higher tensile and flexural strength but lower compressive strength than KH-550 functionalized BNNPs (KH550-BNNPs). These reinforcements are mainly attributed to good BNNPs dispersion and interfacial adhesion between epoxy matrix and BNNPs. This study reveals the potential in improving mechanical properties of BNNPs-containing composites laminates through surface functionalization of BNNPs.

Keywords: boron nitride, epoxy, functionalization, prepreg, composite

Procedia PDF Downloads 418
547 Investigation of Verbal Feedback and Learning Process for Oral Presentation

Authors: Nattawadee Sinpattanawong

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Oral presentation has been used mostly in business communication. The business presentation is carrying out through an audio and visual presentation material such as statistical documents, projectors, etc. Common examples of business presentation are intra-organization and sales presentations. The study aims at investigating functions, strategies and contents of assessors’ verbal feedback on presenters’ oral presentations and exploring presenters’ learning process and specific views and expectations concerning assessors’ verbal feedback related to the delivery of the oral presentation. This study is designed as a descriptive qualitative research; four master students and one teacher in English for Business and Industry Presentation Techniques class of public university will be selected. The researcher hopes that any understanding how assessors’ verbal feedback on oral presentations and learning process may illuminate issues for other people. The data from this research may help to expand and facilitate the readers’ understanding of assessors’ verbal feedback on oral presentations and learning process in their own situations. The research instruments include an audio recorder, video recorder and an interview. The students will be interviewing in order to ask for their views and expectations concerning assessors’ verbal feedback related to the delivery of the oral presentation. After finishing data collection, the data will be analyzed and transcribed. The findings of this study are significant because it can provide presenters knowledge to enhance their learning process and provide teachers knowledge about providing verbal feedback on student’s oral presentations on a business context.

Keywords: business context, learning process, oral presentation, verbal feedback

Procedia PDF Downloads 173
546 Properties Soft Cheese as Diversification of Dangke: A Natural Cheese of South Sulawesi Indonesia

Authors: Ratmawati Malaka, Effendi Abustam, Kusumandari Indah Prahesti, Sudirman Baco

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Dangke is natural cheese from Enrekang South Sulawesi, Indonesia produced through aglutination buffalo milk, cow, goat or sheep using the sap of papaya (Carica papaya). Dangke has been widely known in South Sulawesi but this soft cheese product diversification by using passion fruit juice as milk clotting agents has not been used. Passion fruit juice has a high acidity with a pH of around 4 - 4.5 and has a proteolytic enzyme, so that it can be used to agglutinate milk. The purpose of this study was to investigate the nature Dangke using passion fruit juice as coagulate milk. Dangke made by 10 lt of raw milk by heating at a temperature of 73oC with coagulant passion fruit juice (7.5% and 10%), and added 1% salt. Curd clot and then be formed using a coconut shell, is then pressed until the cheese is compact. The cheese is then observed for 28 days ripening at a temperature of about 5 ° C. Dangke then studied to violence, pH, fat levels and microstructure. Hardness is determined using CD-shear Force, pH is measured using a pH meter Hanna, and fat concentrations were analyzed with methods of proximate. Microstructure viewed using a light microscope with magnification 1000 x. The results showed that the levels of clotting material very significant influence on hardness, pH, and lipid levels. Maturation increase the hardness but lower the pH, the level of fat soft cheese with an average Dangke respectively 21.4% and 30.5% on 7.5% addition of passion fruit juice and 10%. Dangke violence is increasing with the increasing maturation time (1.38 to 3.73 kg / cm), but Dangke pH was decreased by the increase in storage maturation (5.34 to 4.1). Microktrukture cheeses coagulated with 10% of the passion fruit are very firmer and compact with a full globular fat of 7.5%. But the sensory properties of the soft cheese similar in both treatment. The manufacturing process with the addition of coagulant passion fruit juice on making Dangke affect hardness, pH, fat content and microstructure during storage at 5 ° C for 1 d - 28 d.

Keywords: dangke, passion fruits, microstructure, cheese

Procedia PDF Downloads 390
545 The Formation of Thin Copper Films on Graphite Surface Using Magnetron Sputtering Method

Authors: Zydrunas Kavaliauskas, Aleksandras Iljinas, Liutauras Marcinauskas, Mindaugas Milieska, Vitas Valincius

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The magnetron sputtering deposition method is often used to obtain thin film coatings. The main advantage of magnetron vaporization compared to other deposition methods is the high rate erosion of the cathode material (e.g., copper, aluminum, etc.) and the ability to operate under low-pressure conditions. The structure of the formed coatings depends on the working parameters of the magnetron deposition system, which is why it is possible to influence the properties of the growing film, such as morphology, crystal orientation, and dimensions, stresses, adhesion, etc. The properties of these coatings depend on the distance between the substrate and the magnetron surface, the vacuum depth, the gas used, etc. Using this deposition technology, substrates are most often placed near the anode. The magnetic trap of the magnetrons for localization of electrons in the cathode region is formed using a permanent magnet system that is on the side of the cathode. The scientific literature suggests that, after insertion of a small amount of copper into graphite, the electronic conductivity of graphite increase. The aim of this work is to create thin (up to 300 nm) layers on a graphite surface using a magnetron evaporation method, to investigate the formation peculiarities and microstructure of thin films, as well as the mechanism of copper diffusion into graphite inner layers at different thermal treatment temperatures. The electron scanning microscope was used to investigate the microrelief of the coating surface. The chemical composition is determined using the EDS method, which shows that, with an increase of the thermal treatment of the copper-carbon layer from 200 °C to 400 °C, the copper content is reduced from 8 to 4 % in atomic mass units. This is because the EDS method captures only the amount of copper on the graphite surface, while the temperature of the heat treatment increases part of the copper because of the diffusion processes penetrates into the inner layers of the graphite. The XRD method shows that the crystalline copper structure is not affected by thermal treatment.

Keywords: carbon, coatings, copper, magnetron sputtering

Procedia PDF Downloads 267
544 Measurement of Solids Concentration in Hydrocyclone Using ERT: Validation Against CFD

Authors: Vakamalla Teja Reddy, Narasimha Mangadoddy

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Hydrocyclones are used to separate particles into different size fractions in the mineral processing, chemical and metallurgical industries. High speed video imaging, Laser Doppler Anemometry (LDA), X-ray and Gamma ray tomography are previously used to measure the two-phase flow characteristics in the cyclone. However, investigation of solids flow characteristics inside the cyclone is often impeded by the nature of the process due to slurry opaqueness and solid metal wall vessels. In this work, a dual-plane high speed Electrical resistance tomography (ERT) is used to measure hydrocyclone internal flow dynamics in situ. Experiments are carried out in 3 inch hydrocyclone for feed solid concentrations varying in the range of 0-50%. ERT data analysis through the optimized FEM mesh size and reconstruction algorithms on air-core and solid concentration tomograms is assessed. Results are presented in terms of the air-core diameter and solids volume fraction contours using Maxwell’s equation for various hydrocyclone operational parameters. It is confirmed by ERT that the air core occupied area and wall solids conductivity levels decreases with increasing the feed solids concentration. Algebraic slip mixture based multi-phase computational fluid dynamics (CFD) model is used to predict the air-core size and the solid concentrations in the hydrocyclone. Validation of air-core size and mean solid volume fractions by ERT measurements with the CFD simulations is attempted.

Keywords: air-core, electrical resistance tomography, hydrocyclone, multi-phase CFD

Procedia PDF Downloads 361
543 Folk Dance in Asterio Festivals in Ethiopia: Exploration of Performance, Variants, Symbols, and Therapeutic Role

Authors: Meseret Berhanie Menkir

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The present study explores folk dance, one of the folklore texts, its symbols, and its therapeutic role. As a case, the study concentrates on Astrio-Mariam and Merkorios Bera, celebrated on January 30 and February 3 at Deresgie-Mariam Church in Ethiopia. By taking a qualitative stance, the study analyses the meaning of folk dance, explains its role, and describes its types. The data gathered through observation, interview, and focus group discussion techniques are documented in field notes, audio, and video. The data obtained is analyzed using structural-functionalism, psychoanalysis, and semiotics. Accordingly, community members of all ages (mainly the Ethiopian Orthodox Tewahedo Church followers) participate in the performance. While the folk dance is a type of small group dance and group dance, the group has no feature of using men and women performing together. The folk dance's role is a form of healing and spiritual fulfilment besides entertainment. The folk dance also has sword dance characteristics; the study confirmed this feature in content and form. Moreover, the folk dance characterized by frequent shoulder and hand movements Wancha likleka (Horn-mug spin), Doro metet (Chicken drink), and sword dance depict wealth, heroism, and warfare. The instruments used in the performances are also alive, with religious symbols reaching from the drum, incense, and cross to the suffering of Jesus Christ from Hanna to Qeyafa, and references to the 12 Apostles.

Keywords: folk dance, festival, ritual, symbol, therapeutic

Procedia PDF Downloads 34
542 Semi-Automatic Segmentation of Mitochondria on Transmission Electron Microscopy Images Using Live-Wire and Surface Dragging Methods

Authors: Mahdieh Farzin Asanjan, Erkan Unal Mumcuoglu

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Mitochondria are cytoplasmic organelles of the cell, which have a significant role in the variety of cellular metabolic functions. Mitochondria act as the power plants of the cell and are surrounded by two membranes. Significant morphological alterations are often due to changes in mitochondrial functions. A powerful technique in order to study the three-dimensional (3D) structure of mitochondria and its alterations in disease states is Electron microscope tomography. Detection of mitochondria in electron microscopy images due to the presence of various subcellular structures and imaging artifacts is a challenging problem. Another challenge is that each image typically contains more than one mitochondrion. Hand segmentation of mitochondria is tedious and time-consuming and also special knowledge about the mitochondria is needed. Fully automatic segmentation methods lead to over-segmentation and mitochondria are not segmented properly. Therefore, semi-automatic segmentation methods with minimum manual effort are required to edit the results of fully automatic segmentation methods. Here two editing tools were implemented by applying spline surface dragging and interactive live-wire segmentation tools. These editing tools were applied separately to the results of fully automatic segmentation. 3D extension of these tools was also studied and tested. Dice coefficients of 2D and 3D for surface dragging using splines were 0.93 and 0.92. This metric for 2D and 3D for live-wire method were 0.94 and 0.91 respectively. The root mean square symmetric surface distance values of 2D and 3D for surface dragging was measured as 0.69, 0.93. The same metrics for live-wire tool were 0.60 and 2.11. Comparing the results of these editing tools with the results of automatic segmentation method, it shows that these editing tools, led to better results and these results were more similar to ground truth image but the required time was higher than hand-segmentation time

Keywords: medical image segmentation, semi-automatic methods, transmission electron microscopy, surface dragging using splines, live-wire

Procedia PDF Downloads 149
541 Synthesis and Properties of Chitosan-Graft-Polyacrylamide/Gelatin Superabsorbent Composites for Wastewater Purification

Authors: Hafida Ferfera-Harrar, Nacera Aiouaz, Nassima Dairi

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Super absorbents polymers received much attention and are used in many fields because of their superior characters to traditional absorbents, e.g., sponge and cotton. So, it is very important but challenging to prepare highly and fast-swelling super absorbents. A reliable, efficient and low-cost technique for removing heavy metal ions from waste water is the adsorption using bio-adsorbents obtained from biological materials, such as polysaccharides-based hydrogels super absorbents. In this study, novel multi-functional super absorbent composites type semi-interpenetrating polymer networks (Semi-IPNs) were prepared via graft polymerization of acrylamide onto chitosan backbone in presence of gelatin, CTS-g-PAAm/Ge, using potassium persulfate and N,N’ -methylenebisacrylamide as initiator and cross linker, respectively. These hydrogels were also partially hydrolyzed to achieve superabsorbents with ampholytic properties and uppermost swelling capacity. The formation of the grafted network was evidenced by Fourier Transform Infrared Spectroscopy (ATR-FTIR) and thermo gravimetric Analysis (TGA). The porous structures were observed by Scanning Electron Microscope (SEM). From TGA analysis, it was concluded that the incorporation of the Ge in the CTS-g-PAAm network has marginally affected its thermal stability. The effect of gelatin content on the swelling capacities of these super absorbent composites was examined in various media (distilled water, saline and pH-solutions).The water absorbency was enhanced by adding Ge in the network, where the optimum value was reached at 2 wt. % of Ge. Their hydrolysis has not only greatly optimized their absorption capacity but also improved the swelling kinetic. These materials have also showed reswelling ability. We believe that these super-absorbing materials would be very effective for the adsorption of harmful metal ions from waste water.

Keywords: chitosan, gelatin, superabsorbent, water absorbency

Procedia PDF Downloads 437
540 Enhanced Planar Pattern Tracking for an Outdoor Augmented Reality System

Authors: L. Yu, W. K. Li, S. K. Ong, A. Y. C. Nee

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In this paper, a scalable augmented reality framework for handheld devices is presented. The presented framework is enabled by using a server-client data communication structure, in which the search for tracking targets among a database of images is performed on the server-side while pixel-wise 3D tracking is performed on the client-side, which, in this case, is a handheld mobile device. Image search on the server-side adopts a residual-enhanced image descriptors representation that gives the framework a scalability property. The tracking algorithm on the client-side is based on a gravity-aligned feature descriptor which takes the advantage of a sensor-equipped mobile device and an optimized intensity-based image alignment approach that ensures the accuracy of 3D tracking. Automatic content streaming is achieved by using a key-frame selection algorithm, client working phase monitoring and standardized rules for content communication between the server and client. The recognition accuracy test performed on a standard dataset shows that the method adopted in the presented framework outperforms the Bag-of-Words (BoW) method that has been used in some of the previous systems. Experimental test conducted on a set of video sequences indicated the real-time performance of the tracking system with a frame rate at 15-30 frames per second. The presented framework is exposed to be functional in practical situations with a demonstration application on a campus walk-around.

Keywords: augmented reality framework, server-client model, vision-based tracking, image search

Procedia PDF Downloads 264
539 Multimodal Sentiment Analysis With Web Based Application

Authors: Shreyansh Singh, Afroz Ahmed

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Sentiment Analysis intends to naturally reveal the hidden mentality that we hold towards an entity. The total of this assumption over a populace addresses sentiment surveying and has various applications. Current text-based sentiment analysis depends on the development of word embeddings and Machine Learning models that take in conclusion from enormous text corpora. Sentiment Analysis from text is presently generally utilized for consumer loyalty appraisal and brand insight investigation. With the expansion of online media, multimodal assessment investigation is set to carry new freedoms with the appearance of integral information streams for improving and going past text-based feeling examination using the new transforms methods. Since supposition can be distinguished through compelling follows it leaves, like facial and vocal presentations, multimodal opinion investigation offers good roads for examining facial and vocal articulations notwithstanding the record or printed content. These methodologies use the Recurrent Neural Networks (RNNs) with the LSTM modes to increase their performance. In this study, we characterize feeling and the issue of multimodal assessment investigation and audit ongoing advancements in multimodal notion examination in various spaces, including spoken surveys, pictures, video websites, human-machine, and human-human connections. Difficulties and chances of this arising field are additionally examined, promoting our theory that multimodal feeling investigation holds critical undiscovered potential.

Keywords: sentiment analysis, RNN, LSTM, word embeddings

Procedia PDF Downloads 98
538 Synthesis of Highly Active Octahedral NaInS₂ for Enhanced H₂ Evolution

Authors: C. K. Ngaw

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Crystal facet engineering, which involves tuning and controlling a crystal surface and morphology, is a commonly employed strategy to optimize the performance of crystalline nanocrystals. The principle behind this strategy is that surface atomic rearrangement and coordination, which inherently determines their catalytic activity, can be easily tuned by morphological control. Because of this, the catalytic properties of a nanocrystal are closely related to the surface of an exposed facet, and it has provided great motivation for researchers to synthesize photocatalysts with high catalytic activity by maximizing reactive facets exposed through morphological control. In this contribution, octahedral NaInS₂ crystals have been successfully developed via solvothermal method. The formation of the octahedral NaInS₂ crystals was investigated using field emission scanning electron microscope (FESEM) and X-Ray diffraction (XRD), and results have shown that the concentration of sulphur precursor plays an important role in the growth process, leading to the formation of other NaInS₂ crystal structures in the form of hexagonal nanosheets and microspheres. Structural modeling analysis suggests that the octahedral NaInS₂ crystals were enclosed with {012} and {001} facets, while the nanosheets and microspheres are bounded with {001} facets only and without any specific facets, respectively. Visible-light photocatalytic H₂ evolution results revealed that the octahedral NaInS₂ crystals (~67 μmol/g/hr) exhibit ~6.1 and ~2.3 times enhancement as compared to the conventional NaInS₂ microspheres (~11 μmol/g/hr) and nanosheets (~29 μmol/g/hr), respectively. The H₂ enhancement of the NaInS₂ octahedral crystal is attributed to the presence of {012} facets on the surface. Detailed analysis of the octahedron model revealed obvious differences in the atomic arrangement between the {001} and {012} facets and this can affect the interaction between the water molecules and the surface facets before reducing into H₂ gas. These results highlight the importance of tailoring crystal morphology with highly reactive facets in improving photocatalytic properties.

Keywords: H₂ evolution, photocatalysis, octahedral, reactive facets

Procedia PDF Downloads 47
537 Smartphones as a Tool of Mobile Journalism in Saudi Arabia

Authors: Ahmed Deen

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The introduction of the mobile devices which were equipped with internet access and a camera, as well as the messaging services, has become a major inspiration for the use of the mobile devices in the growth in the reporting of news. Mobile journalism (MOJO) was a creation of modern technology, especially the use of mobile technology for video journalism purposes. MOJO, thus, is the process by which information is collected and disseminated to society, through the use of mobile technology, and even the use of the tablets. This paper seeks to better understand the ethics of Saudi mobile journalists towards news coverage. Also, this study aims to explore the relationship between minimizing harms and truth-seeking efforts among Saudi mobile journalists. Three main ethics were targeted in this study, which are seek truth and report it, minimize harm, and being accountable. Diffusion of innovation theory applied to reach this study’s goals. The non- probability sampling approach, ‘Snowball Sampling’ was used to target 124 survey participants, an online survey via SurveyMonkey that was distributed through social media platforms as a web link. The code of ethics of the Society of Professional Journalists has applied as a scale in this study. This study found that the relationship between minimizing harm and truth-seeking efforts is significantly moderate among Saudi mobile journalists. Also, it is found that the level journalistic experiences and using smartphones to cover news are weakly and negatively related to the perceptions of mobile journalism among Saudi journalists, while Saudi journalists who use their smartphone to cover the news between 1-3 years, were the majority of participants (55 participants by 51.4%).

Keywords: mobile journalism, Saudi journalism, smartphone, Saudi Arabia

Procedia PDF Downloads 149