Search results for: single warp beam
4166 The Utilization of Magneto-Hydrodynamics Framework in Expansion of Magnetized Conformal Flow
Authors: Majid Karimabadi, Ahmad Farzaneh Kore, Behnam Azadegan
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The evolution of magnetized quark gluon plasma (QGP) in the framework of magneto- hydrodynamics is the focus of our study. We are investigating the temporal and spatial evolution of QGP using a second order viscous hydrodynamic framework. The fluid is considered to be magnetized and subjected to the influence of a magnetic field that is generated during the early stages of relativistic heavy ion collisions. We assume boost invariance along the beam line, which is represented by the z coordinate, and fluid expansion in the x direction. Additionally, we assume that the magnetic field is perpendicular to the reaction plane, which corresponds to the y direction. The fluid is considered to have infinite electrical conductivity. To analyze this system, we solve the coupled Maxwell and conservation equations. By doing so, we are able to determine the time and space dependence of the energy density, velocity, and magnetic field in the transverse plane of the viscous magnetized hot plasma. Furthermore, we obtain the spectrum of hadrons and compare it with experimental data.Keywords: QGP, magnetohydrodynamics, hadrons, conversation
Procedia PDF Downloads 684165 Evaluation of the Use of U-Wrap Anchorage Systems for Strengthening Concrete Members Reinforced by Fiber Reinforced-Polymer Laminate
Authors: Mai A. Aljaberi
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The anchorage of fibre-reinforced polymer (FRP) sheets is the most effective solution to prevent or delay debonding failure; this system has proven to get better levels of FRP utilization. Unfortunately, the related design information is still unclear. This shortcoming limits the widespread use of the anchorage system. In order to minimize the knowledge gap about the design of U-wrap anchors, this paper reports the results of tested beams which were strengthened with carbon fiber-reinforced polymer (CFRP) sheets at their tension sides and secured with U-wrap anchors at each end of the longitudinal CFRP. The beams were tested under four-point loading until failure. The parameters examined include the compressive strength of the concrete and the number of longitudinal CFRP. It is concluded that these parameters have a considerable effect on the debonding of the strain. The greatest improvement in the strain was 55.8% over the control beam.Keywords: CFRP, concrete strengthening, debonding failure, debonding strain, U-wrap anchor
Procedia PDF Downloads 844164 Efficacy of Single-Dose Azithromycin Therapy for the Treatment of Chlamydia trachomatis in Patients Evaluated for Child Sexual Abuse in an Urban Health Center 2006-16
Authors: Trenton Hubbard, Kenneth Soyemi, Emily Siffermann
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Introduction: According to the American Academy of Pediatrics (AAP) there are different weight-based recommendations for the treatment of Chlamydia trachomatis (CT) in patients who are being evaluated for sexual assault. Current AAP Red Book guidelines recommend that uncomplicated C. trachomatis anogenital infection in prepubertal patients weighing less than =<45 kg be treated with oral erythromycin 50 mg/kg/day QID for 14 days with no alternative therapies, and for patients whose weight => 45 kg are Azithromycin 1 gm PO once. Our study objective was to determine the efficacy of single-dose Azithromycin therapy for the treatment of Chlamydia trachomatis in patients weighing less than 50 kg who were evaluated for child sexual abuse in an urban setting. Methods: We conducted a retrospective chart review of historical medical records (paper and electronic) patients weighing less than 50 kg who were evaluated for child sexual abuse and subsequently treated for C. trachomatis infection with Azithromycin (20 mg/kg PO once up to a maximum 1 gm) and received a Test of Cure (TOC) from 2006-2016. Qualitative variables were expressed as percentages. Quantitative variables were expressed as mean values (+/- standard deviation [SD]) if they followed a normal distribution or as median values (interquartile range[IQR]) if they did not. Wilcoxson two-sample test was used to compare means of Azithromycin Dose, mg/kg, and TOC timing between treatment responders and non-responders. Results: We reviewed records of 34 patients, average age (SD) was 5.4 (2.0) years, 33 (97%) were treated for CT and 1(3%) for both GC and CT. 25 (74%) were females. Urine PCR was the most commonly used test at evaluation and as TOC with 13 (38%) patients completing both tests. The average (SD) dose of Azithromycin at treatment was 470 (136) mg and average (SD) mg/kg dose of 20 (1.9) mg/kg for all patients. Median (IQR) timing for TOC testing was 19 (14-26) days. Of the 33 with complete data 25 (74%) had a negative TOC. When compared with treatment non-responders (TOC failures), treatment responders received higher doses (average dose (SD) received 495 (139) vs 401(110), P 0.06)); similar average (SD) weight base dosing received (20.8(2.0) vs 19.7 (1.5), P 0.15)), and earlier average (SD)TOC test timing (18.8 (5.6) vs 32 (28.6) P 0.02)). Conclusion: Azithromycin dosing appears to be efficacious in the treatment of CT post sexual assault as majority of patients responded. Although treatment responders and non-responders received similar weight based doses, there is need for additional studies to understand variances and predictors of response.Keywords: child sexual abuse, chlmaydia trachmotis infection, single-dose azithromycin, weight less than or equal to 45 kilograms
Procedia PDF Downloads 2944163 Dynamic Process of Single Water Droplet Impacting on a Hot Heptane Surface
Authors: Mingjun Xu, Shouxiang Lu
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Understanding the interaction mechanism between the water droplet and pool fire has an important significance in engineering application of water sprinkle/spray/mist fire suppression. The micro impact process is unclear when the droplet impacts on the burning liquid surface at present. To deepen the understanding of the mechanisms of pool fire suppression with water spray/mist, dynamic processes of single water droplet impinging onto a hot heptane surface are visualized with the aid of a high-speed digital camera at 2000 fps. Each test is repeated 20 times. The water droplet diameter is around 1.98 mm, and the impact Weber number ranges from 30 to 695. The heptane is heated by a hot plate to mimic the burning condition, and the temperature varies from 30 to 90°C. The results show that three typical phenomena, including penetration, crater-jet and surface bubble, are observed, and the pool temperature has a significant influence on the critical condition for the appearance of each phenomenon. A global picture of different phenomena is built according to impact Weber number and pool temperature. In addition, the pool temperature and Weber number have important influences on the characteristic parameters including maximum crater depth, crown height and liquid column height. For a fixed Weber number, the liquid column height increases with pool temperature.Keywords: droplet impact, fire suppression, hot surface, water spray
Procedia PDF Downloads 2434162 Submodeling of Mega-Shell Reinforced Concrete Solar Chimneys
Authors: Areeg Shermaddo, Abedulgader Baktheer
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Solar updraft power plants (SUPPs) made from reinforced concrete (RC) are an innovative technology to generate solar electricity. An up to 1000 m high chimney represents the major part of each SUPP ensuring the updraft of the warmed air from the ground. Numerical simulation of nonlinear behavior of such large mega shell concrete structures is a challenging task, and computationally expensive. A general finite element approach to simulate reinforced concrete bearing behavior is presented and verified on a simply supported beam, as well as the technique of submodeling. The verified numerical approach is extended and consecutively transferred to a more complex chimney structure of a SUPP. The obtained results proved the reliability of submodeling technique in analyzing critical regions of simple and complex mega concrete structures with high accuracy and dramatic decrease in the computation time.Keywords: ABAQUS, nonlinear analysis, submodeling, SUPP
Procedia PDF Downloads 2194161 Study of Debonding of Composite Material from a Deforming Concrete Beam Using Infrared Thermography
Authors: Igor Shardakov, Anton Bykov, Alexey Shestakov, Irina Glot
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This article focuses on the cycle of experimental studies of the formation of cracks and debondings in the concrete reinforced with carbon fiber. This research was carried out in Perm National Research Polytechnic University. A series of CFRP-strengthened RC beams was tested to investigate the influence of preload and crack repairing factors on CFRP debonding. IRT was applied to detect the early stage of IC debonding during the laboratory bending tests. It was found that for the beams strengthened under load after crack injecting, СFRP debonding strain is 4-65% lower than for the preliminary strengthened beams. The beams strengthened under the load had a relative area of debonding of 2 times higher than preliminary strengthened beams. The СFRP debonding strain is weakly dependent on the strength of the concrete substrate. For beams with a transverse wrapping anchorage in support sections FRP debonding is not a failure mode.Keywords: IC debonding, infrared thermography, non-destructive testing methods, quality control, strengthening
Procedia PDF Downloads 2674160 Body Perception and Self-Esteem in Individuals Performing Bodybuilding Exercise Program
Authors: Yildiz Erdoganoglu, Unzile Tunc
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The aim of this study was to determine the relationship of body, upper extremity, lower extremity endurance, and core functionality with body perception and self-esteem in individuals who applied for a bodybuilding exercise program. Forty volunteer male subjects who underwent bodybuilding exercises for one year or more were included in the study. After obtaining demographic information of the individuals, trunk endurance was evaluated by curl-up and modified Sorensen test, upper extremity endurance by push-up test, lower extremity endurance by repeated squat test, core functionalities by single-leg wall sitting and repeated single-leg squatting tests. body perception, body image perception scale, and self-esteem were evaluated with Rosenberg self-esteem scale. The mean age of the individuals was 25.60 ± 4.70 years, mean exercise time was 22.47 ± 34.60 months. At the end of the study, body perception was low, and self-esteem was moderate. There was no significant relationship between abdominal endurance, back extensor endurance, upper extremity, and lower extremity endurance, core functionality, and body perception (p > 0.05). Also, there was no significant relationship between abdominal extensor, back extensor, upper extremity and lower extremity endurance, core functionality, and self-esteem (p > 0.05). The body, upper and lower extremity endurance, and core functionality of bodybuilders did not have any effect on body perception and self-esteem, suggesting that these individuals did not contribute positively to their efforts to improve their body perception and self- esteem.Keywords: body endurance, body perception, core functionality, self esteem
Procedia PDF Downloads 1524159 Optimal Analysis of Structures by Large Wing Panel Using FEM
Authors: Byeong-Sam Kim, Kyeongwoo Park
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In this study, induced structural optimization is performed to compare the trade-off between wing weight and induced drag for wing panel extensions, construction of wing panel and winglets. The aerostructural optimization problem consists of parameters with strength condition, and two maneuver conditions using residual stresses in panel production. The results of kinematic motion analysis presented a homogenization based theory for 3D beams and 3D shells for wing panel. This theory uses a kinematic description of the beam based on normalized displacement moments. The displacement of the wing is a significant design consideration as large deflections lead to large stresses and increased fatigue of components cause residual stresses. The stresses in the wing panel are small compared to the yield stress of aluminum alloy. This study describes the implementation of a large wing panel, aerostructural analysis and structural parameters optimization framework that couples a three-dimensional panel method.Keywords: wing panel, aerostructural optimization, FEM, structural analysis
Procedia PDF Downloads 5914158 The Laser Line Detection for Autonomous Mapping Based on Color Segmentation
Authors: Pavel Chmelar, Martin Dobrovolny
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Laser projection or laser footprint detection is today widely used in many fields of robotics, measurement, or electronics. The system accuracy strictly depends on precise laser footprint detection on target objects. This article deals with the laser line detection based on the RGB segmentation and the component labeling. As a measurement device was used the developed optical rangefinder. The optical rangefinder is equipped with vertical sweeping of the laser beam and high quality camera. This system was developed mainly for automatic exploration and mapping of unknown spaces. In the first section is presented a new detection algorithm. In the second section are presented measurements results. The measurements were performed in variable light conditions in interiors. The last part of the article present achieved results and their differences between day and night measurements.Keywords: color segmentation, component labelling, laser line detection, automatic mapping, distance measurement, vector map
Procedia PDF Downloads 4324157 Fracture Crack Monitoring Using Digital Image Correlation Technique
Authors: B. G. Patel, A. K. Desai, S. G. Shah
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The main of objective of this paper is to develop new measurement technique without touching the object. DIC is advance measurement technique use to measure displacement of particle with very high accuracy. This powerful innovative technique which is used to correlate two image segments to determine the similarity between them. For this study, nine geometrically similar beam specimens of different sizes with (steel fibers and glass fibers) and without fibers were tested under three-point bending in a closed loop servo-controlled machine with crack mouth opening displacement control with a rate of opening of 0.0005 mm/sec. Digital images were captured before loading (unreformed state) and at different instances of loading and were analyzed using correlation techniques to compute the surface displacements, crack opening and sliding displacements, load-point displacement, crack length and crack tip location. It was seen that the CMOD and vertical load-point displacement computed using DIC analysis matches well with those measured experimentally.Keywords: Digital Image Correlation, fibres, self compacting concrete, size effect
Procedia PDF Downloads 3894156 Effect of Strength Class of Concrete and Curing Conditions on Capillary Water Absorption of Self-Compacting and Conventional Concrete
Authors: E. Ebru Demirci, Remzi Şahin
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The purpose of this study is to compare Self Compacting Concrete (SCC) and Conventional Concrete (CC) in terms of their capillary water absorption. During the comparison of SCC and CC, the effects of two different factors were also investigated: concrete strength class and curing condition. In the study, both SCC and CC were produced in three different concrete classes (C25, C50 and C70) and the other parameter (i.e curing condition) was determined as two levels: moisture and air curing. It was observed that, for both curing environments and all strength classes of concrete, SCCs had lower capillary water absorption values than that of CCs. It was also detected that, for both SCC and CC, capillary water absorption values of samples kept in moisture curing were significantly lower than that of samples stored in air curing. Additionally, it was determined that capillary water absorption values for both SCC and CC decrease with increasing strength class of concrete for both curing environments.Keywords: capillary water absorption, curing condition, reinforced concrete beam, self-compacting concrete
Procedia PDF Downloads 3364155 Laser Micro-Welding of an Isomorphous System with Different Geometries: An Investigation on the Mechanical Properties and Microstructure of the Joint
Authors: Mahdi Amne Elahi, Marcus Koch, Peter Plapper
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Due to the demand of miniaturizing in automotive industry, the application of laser welding is quite promising. The current study focused on laser micro-welding of CuSn6 bronze and nickel wire for a miniature electromechanical hybrid component. Due to the advantages of laser welding, the welding can be tailored specifically for the requirements of the part. Scanning electron and optical microscopy were implemented to study the microstructure and tensile-shear test was selected to represent the mechanical properties. Different welding sides, beam oscillations, and speeds have been investigated to optimize the tensile-shear load and microstructure. The results show that the mechanical properties and microstructure of the joint is highly under the influence of the mentioned parameters. Due to the lack of intermetallic compounds, the soundness of the joint is achievable by manipulating the geometry of the weld seam and minimize weld defects.Keywords: bronze, laser micro-welding, microstructure, nickel, tensile shear test
Procedia PDF Downloads 1664154 Following the Modulation of Transcriptional Activity of Genes by Chromatin Modifications during the Cell Cycle in Living Cells
Authors: Sharon Yunger, Liat Altman, Yuval Garini, Yaron Shav-Tal
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Understanding the dynamics of transcription in living cells has improved since the development of quantitative fluorescence-based imaging techniques. We established a method for following transcription from a single copy gene in living cells. A gene tagged with MS2 repeats, used for mRNA tagging, in its 3' UTR was integrated into a single genomic locus. The actively transcribing gene was detected and analyzed by fluorescence in situ hybridization (FISH) and live-cell imaging. Several cell clones were created that differed in the promoter regulating the gene. Thus, comparative analysis could be obtained without the risk of different position effects at each integration site. Cells in S/G2 phases could be detected exhibiting two adjacent transcription sites on sister chromatids. A sharp reduction in the transcription levels was observed as cells progressed along the cell cycle. We hypothesized that a change in chromatin structure acts as a general mechanism during the cell cycle leading to down-regulation in the activity of some genes. We addressed this question by treating the cells with chromatin decondensing agents. Quantifying and imaging the treated cells suggests that chromatin structure plays a role both in regulating transcriptional levels along the cell cycle, as well as in limiting an active gene from reaching its maximum transcription potential at any given time. These results contribute to understanding the role of chromatin as a regulator of gene expression.Keywords: cell cycle, living cells, nucleus, transcription
Procedia PDF Downloads 3124153 Mechanical and Durability Characteristics of Roller Compacted Geopolymer Concrete Using Recycled Concrete Aggregate
Authors: Syfur Rahman, Mohammad J. Khattak
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Every year a huge quantity of recycling concrete aggregate (RCA) is generated in the United States of America. Utilization of RCA can solve the storage problem, prevent environmental pollution, and reduce the construction cost. However, due to the overall low strength and durability characteristics of RCA, its usages are limited to a certain area like a landfill, low strength base material, replacement of a few percentages of virgin aggregates in Portland cement concrete, etc. This study focuses on the improvement of the strength and durability characteristics of RCA by introducing the concept of roller-compacted geopolymer concrete. In this research, developed roller-compacted geopolymer concrete (RCGPC) and roller-compacted cement concrete (RCC) mixtures containing 100% recycled concrete aggregate were evaluated and compared. Several selected RCGPC mixtures were investigated to find out the effect of mixture variables, including sodium hydroxide (NaOH) molar concentration, sodium silicate (Na₂SiO₃), to sodium hydroxide (NaOH) ratio on the strength, stiffness and durability characteristics of the developed RCGPC. Sodium hydroxide (NaOH) and sodium silicate (Na₂SiO₃) were mixed in different ratios to synthesize the alkali activator. American Concrete Pavement Association (ACPA) recommended RCC gradation was used with a maximum nominal aggregate size of 19 mm with a 4% fine particle passing 0.075 mm sieve. The mixtures were made using NaOH molar concentration of 8M and 10M along with, Na₂SiO₃ to NaOH ratio of 0 and 1 by mass and 15% class F fly ash. Optimum alkali content and moisture content were determined for each RCGPC and RCC mixtures, respectively, using modified proctor test. Compressive strength, semi-circular bending beam strength, and dynamic modulus test were conducted to evaluate the mechanistic characteristics of both mixtures. To determine the optimum curing conditions for RCGPC, effects of different curing temperature and curing duration on compressive strength were also studied. Sulphate attack and freeze-thaw tests were also carried out to assess the durability properties of the developed mixtures. X-ray diffraction (XRD) was used for morphology and microstructure analysis. From the optimum moisture content results, it was found that RCGPC has high alkali content, which was mainly due to the high absorption capacity of RCA. It was found that the mixtures with Na₂SiO₃ to NaOH ratio of 1 yielded about 60% higher compressive strength than the ratio of 0. Further, the mixtures using 10M NaOH concentrations and alkali ratio of 1 produced about 28 MPa of compressive strength, which was around 33% higher than 8M NaOH mixtures. Similar results were obtained for elastic and dynamic modulus of the mixtures. On the other hand, the semi-circular bending beam strength remained the same for both 8 and 10 molar NaOH geopolymer mixtures. Formation of new geopolymeric compounds and chemical bonds in the newly formed novel RCGPC mixtures were also discovered using XRD analysis. The results of mechanical and durability testing further revealed that RCGPC performed similarly to that of RCC mixtures. Based on the results of mechanical and durability testing, the developed RCGPC mixtures using 100% recycled concrete could be used as a cost-effective solution for the construction of pavement structures.Keywords: roller compacted concrete, geopolymer concrete, recycled concrete aggregate, concrete pavement, fly ash
Procedia PDF Downloads 1384152 Effect of Number of Baffles on Pressure Drop and Heat Transfer in a Shell and Tube Heat Exchanger
Authors: A. Falavand Jozaei, A. Ghafouri, M. Mosavi Navaei
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In this paper for a given heat duty, study of number of baffles on pressure drop and heat transfer is considered in a STHX (Shell and Tube Heat Exchanger) with single segmental baffles. The effect of number of baffles from 9 to 52 baffles (baffle spacing variations from 4 to 24 inches) over OHTC (Overall Heat Hransfer Coefficient) to pressure drop ratio (U/Δp ratio). The results show that U/Δp ratio is low when baffle spacing is minimum (4 inches) because pressure drop is high; however, heat transfer coefficient is very significant. Then, with the increase of baffle spacing, pressure drop rapidly decreases and OHTC also decreases, but the decrease of OHTC is lower than pressure drop, so (U/Δp) ratio increases. After increasing baffles more than 12 inches, variation in pressure drop is gradual and approximately constant and OHTC decreases; Consequently, U/Δp ratio decreases again. If baffle spacing reaches to 24 inches, STHX will have minimum pressure drop, but OHTC decreases, so required heat transfer surface increases and U/Δp ratio decreases. After baffle spacing more than 12 inches, variation of shell side pressure drop is negligible. So optimum baffle spacing is suggested between 8 to 12 inches (43 to 63 percent of inside shell diameter) for a sufficient heat duty and low pressure drop.Keywords: shell and tube heat exchanger, single segmental baffle, overall heat transfer coefficient, pressure drop
Procedia PDF Downloads 5474151 A Highly Efficient Broadcast Algorithm for Computer Networks
Authors: Ganesh Nandakumaran, Mehmet Karaata
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A wave is a distributed execution, often made up of a broadcast phase followed by a feedback phase, requiring the participation of all the system processes before a particular event called decision is taken. Wave algorithms with one initiator such as the 1-wave algorithm have been shown to be very efficient for broadcasting messages in tree networks. Extensions of this algorithm broadcasting a sequence of waves using a single initiator have been implemented in algorithms such as the m-wave algorithm. However as the network size increases, having a single initiator adversely affects the message delivery times to nodes further away from the initiator. As a remedy, broadcast waves can be allowed to be initiated by multiple initiator nodes distributed across the network to reduce the completion time of broadcasts. These waves initiated by one or more initiator processes form a collection of waves covering the entire network. Solutions to global-snapshots, distributed broadcast and various synchronization problems can be solved efficiently using waves with multiple concurrent initiators. In this paper, we propose the first stabilizing multi-wave sequence algorithm implementing waves started by multiple initiator processes such that every process in the network receives at least one sequence of broadcasts. Due to being stabilizing, the proposed algorithm can withstand transient faults and do not require initialization. We view a fault as a transient fault if it perturbs the configuration of the system but not its program.Keywords: distributed computing, multi-node broadcast, propagation of information with feedback and cleaning (PFC), stabilization, wave algorithms
Procedia PDF Downloads 5044150 A Study of Structural Damage Detection for Spacecraft In-Orbit Based on Acoustic Sensor Array
Authors: Lei Qi, Rongxin Yan, Lichen Sun
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With the increasing of human space activities, the number of space debris has increased dramatically, and the possibility that spacecrafts on orbit are impacted by space debris is growing. A method is of the vital significance to real-time detect and assess spacecraft damage, determine of gas leak accurately, guarantee the life safety of the astronaut effectively. In this paper, acoustic sensor array is used to detect the acoustic signal which emits from the damage of the spacecraft on orbit. Then, we apply the time difference of arrival and beam forming algorithm to locate the damage and leakage. Finally, the extent of the spacecraft damage is evaluated according to the nonlinear ultrasonic method. The result shows that this method can detect the debris impact and the structural damage, locate the damage position, and identify the damage degree effectively. This method can meet the needs of structural damage detection for the spacecraft in-orbit.Keywords: acoustic sensor array, spacecraft, damage assessment, leakage location
Procedia PDF Downloads 2964149 Raman Spectroscopy of Fossil-like Feature in Sooke #1 from Vancouver Island
Authors: J. A. Sawicki, C. Ebrahimi
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The first geochemical, petrological, X-ray diffraction, Raman, Mössbauer, and oxygen isotopic analyses of very intriguing 13-kg Sooke #1 stone covered in 70% of its surface with black fusion crust, found in and recovered from Sooke Basin, near Juan de Fuca Strait, in British Columbia, were reported as poster #2775 at LPSC52 in March. Our further analyses reported in poster #6305 at 84AMMS in August and comparisons with the Mössbauer spectra of Martian meteorite MIL03346 and Martian rocks in Gusev Crater reported by Morris et al. suggest that Sooke #1 find could be a stony achondrite of Martian polymict breccia type ejected from early watery Mars. Here, the Raman spectra of a carbon-rich ~1-mm² fossil-like white area identified in this rock on a surface of polished cut have been examined in more detail. The low-intensity 532 nm and 633 nm beams of the InviaRenishaw microscope were used to avoid any destructive effects. The beam was focused through the microscope objective to a 2 m spot on a sample, and backscattered light collected through this objective was recorded with CCD detector. Raman spectra of dark areas outside fossil have shown bands of clinopyroxene at 320, 660, and 1020 cm-1 and small peaks of forsteritic olivine at 820-840 cm-1, in agreement with results of X-ray diffraction and Mössbauer analyses. Raman spectra of the white area showed the broad band D at ~1310 cm-1 consisting of main mode A1g at 1305 cm⁻¹, E2g mode at 1245 cm⁻¹, and E1g mode at 1355 cm⁻¹ due to stretching diamond-like sp3 bonds in diamond polytype lonsdaleite, as in Ovsyuk et al. study. The band near 1600 cm-1 mostly consists of D2 band at 1620 cm-1 and not of the narrower G band at 1583 cm⁻¹ due to E2g stretching in planar sp2 bonds that are fundamental building blocks of carbon allotropes graphite and graphene. In addition, the broad second-order Raman bands were observed with 532 nm beam at 2150, ~2340, ~2500, 2650, 2800, 2970, 3140, and ~3300 cm⁻¹ shifts. Second-order bands in diamond and other carbon structures are ascribed to the combinations of bands observed in the first-order region: here 2650 cm⁻¹ as 2D, 2970 cm⁻¹ as D+G, and 3140 cm⁻¹ as 2G ones. Nanodiamonds are abundant in the Universe, found in meteorites, interplanetary dust particles, comets, and carbon-rich stars. The diamonds in meteorites are presently intensely investigated using Raman spectroscopy. Such particles can be formed by CVD process and during major impact shocks at ~1000-2300 K and ~30-40 GPa. It cannot be excluded that the fossil discovered in Sooke #1 could be a remnant of an alien carbon organism that transformed under shock impact to nanodiamonds. We trust that for the benefit of research in astro-bio-geology of meteorites, asteroids, Martian rocks, and soil, this find deserves further, more thorough investigations. If possible, the Raman SHERLOCK spectrometer operating on the Perseverance Rover should also search for such objects in the Martian rocks.Keywords: achondrite, nanodiamonds, lonsdaleite, raman spectra
Procedia PDF Downloads 1514148 Anaerobic Co-digestion in Two-Phase TPAD System of Sewage Sludge and Fish Waste
Authors: Rocio López, Miriam Tena, Montserrat Pérez, Rosario Solera
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Biotransformation of organic waste into biogas is considered an interesting alternative for the production of clean energy from renewable sources by reducing the volume and organic content of waste Anaerobic digestion is considered one of the most efficient technologies to transform waste into fertilizer and biogas in order to obtain electrical energy or biofuel within the concept of the circular economy. Currently, three types of anaerobic processes have been developed on a commercial scale: (1) single-stage process where sludge bioconversion is completed in a single chamber, (2) two-stage process where the acidogenic and methanogenic stages are separated into two chambers and, finally, (3) temperature-phase sequencing (TPAD) process that combines a thermophilic pretreatment unit prior to mesophilic anaerobic digestion. Two-stage processes can provide hydrogen and methane with easier control of the first and second stage conditions producing higher total energy recovery and substrate degradation than single-stage processes. On the other hand, co-digestion is the simultaneous anaerobic digestion of a mixture of two or more substrates. The technology is similar to anaerobic digestion but is a more attractive option as it produces increased methane yields due to the positive synergism of the mixtures in the digestion medium thus increasing the economic viability of biogas plants. The present study focuses on the energy recovery by anaerobic co-digestion of sewage sludge and waste from the aquaculture-fishing sector. The valorization is approached through the application of a temperature sequential phase process or TPAD technology (Temperature - Phased Anaerobic Digestion). Moreover, two-phase of microorganisms is considered. Thus, the selected process allows the development of a thermophilic acidogenic phase followed by a mesophilic methanogenic phase to obtain hydrogen (H₂) in the first stage and methane (CH₄) in the second stage. The combination of these technologies makes it possible to unify all the advantages of these anaerobic digestion processes individually. To achieve these objectives, a sequential study has been carried out in which the biochemical potential of hydrogen (BHP) is tested followed by a BMP test, which will allow checking the feasibility of the two-stage process. The best results obtained were high total and soluble COD yields (59.8% and 82.67%, respectively) as well as H₂ production rates of 12LH₂/kg SVadded and methane of 28.76 L CH₄/kg SVadded for TPAD.Keywords: anaerobic co-digestion, TPAD, two-phase, BHP, BMP, sewage sludge, fish waste
Procedia PDF Downloads 1564147 Sensor Network Structural Integration for Shape Reconstruction of Morphing Trailing Edge
Authors: M. Ciminello, I. Dimino, S. Ameduri, A. Concilio
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Improving aircraft's efficiency is one of the key elements of Aeronautics. Modern aircraft possess many advanced functions, such as good transportation capability, high Mach number, high flight altitude, and increasing rate of climb. However, no aircraft has a possibility to reach all of this optimized performance in a single airframe configuration. The aircraft aerodynamic efficiency varies considerably depending on the specific mission and on environmental conditions within which the aircraft must operate. Structures that morph their shape in response to their surroundings may at first seem like the stuff of science fiction, but take a look at nature and lots of examples of plants and animals that adapt to their environment would arise. In order to ensure both the controllable and the static robustness of such complex structural systems, a monitoring network is aimed at verifying the effectiveness of the given control commands together with the elastic response. In order to achieve this kind of information, the use of FBG sensors network is, in this project, proposed. The sensor network is able to measure morphing structures shape which may show large, global displacements due to non-standard architectures and materials adopted. Chord -wise variations may allow setting and chasing the best layout as a function of the particular and transforming reference state, always targeting best aerodynamic performance. The reason why an optical sensor solution has been selected is that while keeping a few of the contraindication of the classical systems (like cabling, continuous deployment, and so on), fibre optic sensors may lead to a dramatic reduction of the wires mass and weight thanks to an extreme multiplexing capability. Furthermore, the use of the ‘light’ as ‘information carrier’, permits dealing with nimbler, non-shielded wires, and avoids any kind of interference with the on-board instrumentation. The FBG-based transducers, herein presented, aim at monitoring the actual shape of adaptive trailing edge. Compared to conventional systems, these transducers allow more fail-safe measurements, by taking advantage of a supporting structure, hosting FBG, whose properties may be tailored depending on the architectural requirements and structural constraints, acting as strain modulator. The direct strain may, in fact, be difficult because of the large deformations occurring in morphing elements. A modulation transducer is then necessary to keep the measured strain inside the allowed range. In this application, chord-wise transducer device is a cantilevered beam sliding trough the spars and copying the camber line of the ATE ribs. FBG sensors array position are dimensioned and integrated along the path. A theoretical model describing the system behavior is implemented. To validate the design, experiments are then carried out with the purpose of estimating the functions between rib rotation and measured strain.Keywords: fiber optic sensor, morphing structures, strain sensor, shape reconstruction
Procedia PDF Downloads 3294146 Perpetrators of Ableist Sexual Violence: Understanding Who They Are and Why They Target People with Intellectual Disabilities in Australia
Authors: Michael Rahme
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Over the past decade, there is an overwhelming consensus spanning across academia, government commissions, and civil societies that concede that individuals with disabilities (IWDs), particularly those with intellectual differences, are a demographic most ‘vulnerable’ to experiences of sexual violence. From this global accord, numerous policies have sprouted in the protection of this ‘pregnable’ sector of society, primarily framed around liberal obligations of stewardship over the ‘defenceless.’ As such, these initiatives mainly target post-incident or victim-based factors of sexual violence, which is apparent in proposals for more inclusive sexual education and accessible contact lines for IWDs. Yet despite the necessity of these initiatives, sexual incidents among this demographic persist and, in nations such as Australia, continue to rise. Culture of Violence theory reveals that such discrepancies in theory and practice stem from societal structures that frame individuals as ‘vulnerable’, ‘impregnable’, or ‘defenceless’ because of their disability, thus propagating their own likelihood of abuse. These structures, as embodied by the Australian experience, allow these sexual violences to endure through cultural ideologies that place the IWDs ‘failures’ at fault while sidelining the institutions that permit this abuse. Such is representative of the initiatives of preventative organizations like People with Disabilities Australia, which have singularly strengthened victim protection networks, despite abuse continuing to rise dramatically among individuals with intellectual disabilities alone. Yet regardless of this rise, screenings of families and workers remain inadequate and practically untouched, a reflection of a tremendous societal warp in understanding surrounding the lived experiences of IWDs. This theory is also representative of broader literature, where the study of the perpetrators of disability rights, particularly sexual rights, is almost unapparent in a field that is already seldom studied. Therefore, placing power on the abuser via stripping that of the victims. As such, the Culture of Violence theory (CVT) sheds light on the institutions that allow these perpetrators to prosper. This paper, taking a CVT approach, aims to dissipate this discrepancy in the Australian experience by way of a qualitative analysis of all available court proceedings and tribunals between 2020-2022. Through an analysis of the perpetrator, their relation to the IWD, and the motives for their actions granted by court and tribunal transcripts and the psychological, and behavioural reports, among other material, that have been presented and consulted during these proceedings. All of which would be made available under the 1982 Freedom of Information Act. The findings from this study, through the incorporation of CVT, determine the institutions in which these abusers function and the ideologies which motivate such behaviour; while being conscious of the issue of re-traumatization and language barriers of the abusees. Henceforth, this study aims to be a potential policy guide on strengthening support institutions that provide IWDs with their basic rights. In turn, undermining sexual violence among individuals with intellectual disabilities at its roots.Keywords: criminal profiling, intellectual disabilities, prevention, sexual violence
Procedia PDF Downloads 934145 Minimum Ratio of Flexural Reinforcement for High Strength Concrete Beams
Authors: Azad A. Mohammed, Dunyazad K. Assi, Alan S. Abdulrahman
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Current ACI 318 Code provides two limits for minimum steel ratio for concrete beams. When concrete compressive strength be larger than 31 MPa the limit of √(fc')/4fy usually governs. In this paper shortcomings related to using this limit was fairly discussed and showed that the limit is based on 90% safety factor and was derived based on modulus of rupture equation suitable for concretes of compressive strength lower than 31 MPa. Accordingly, the limit is nor suitable and critical for concretes of higher compressive strength. An alternative equation was proposed for minimum steel ratio of rectangular beams and was found that the proposed limit is accurate for beams of wide range of concrete compressive strength. Shortcomings of the current ACI 318 Code equation and accuracy of the proposed equation were supported by test data obtained from testing six reinforced concrete beams.Keywords: concrete beam, compressive strength, minimum steel ratio, modulus of rupture
Procedia PDF Downloads 5534144 Comet Assay: A Promising Tool for the Risk Assessment and Clinical Management of Head and Neck Tumors
Authors: Sarim Ahmad
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The Single Cell Gel Electrophoresis Assay (SCGE, known as comet assay) is a potential, uncomplicated, sensitive and state-of-the-art technique for quantitating DNA damage at individual cell level and repair from in vivo and in vitro samples of eukaryotic cells and some prokaryotic cells, being popular in its widespread use in various areas including human biomonitoring, genotoxicology, ecological monitoring and as a tool for research into DNA damage or repair in different cell types in response to a range of DNA damaging agents, cancer risk and therapy. The method involves the encapsulation of cells in a low-melting-point agarose suspension, lysis of the cells in neutral or alkaline (pH > 13) conditions, and electrophoresis of the suspended lysed cells, resulting in structures resembling comets as observed by fluorescence microscopy; the intensity of the comet tail relative to the head reflects the number of DNA breaks. The likely basis for this is that loops containing a break lose their supercoiling and become free to extend towards the anode. This is followed by visual analysis with staining of DNA and calculating fluorescence to determine the extent of DNA damage. This can be performed by manual scoring or automatically by imaging software. The assay can, therefore, predict an individual’s tumor sensitivity to radiation and various chemotherapeutic drugs and further assess the oxidative stress within tumors and to detect the extent of DNA damage in various cancerous and precancerous lesions of oral cavity.Keywords: comet assay, single cell gel electrophoresis, DNA damage, early detection test
Procedia PDF Downloads 2924143 Influence of Flexural Reinforcement on the Shear Strength of RC Beams Without Stirrups
Authors: Guray Arslan, Riza Secer Orkun Keskin
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Numerical investigations were conducted to study the influence of flexural reinforcement ratio on the diagonal cracking strength and ultimate shear strength of reinforced concrete (RC) beams without stirrups. Three-dimensional nonlinear finite element analyses (FEAs) of the beams with flexural reinforcement ratios ranging from 0.58% to 2.20% subjected to a mid-span concentrated load were carried out. It is observed that the load-deflection and load-strain curves obtained from the numerical analyses agree with those obtained from the experiments. It is concluded that flexural reinforcement ratio has a significant effect on the shear strength and deflection capacity of RC beams without stirrups. The predictions of the diagonal cracking strength and ultimate shear strength of beams obtained by using the equations defined by a number of codes and researchers are compared with each other and with the experimental values.Keywords: finite element, flexural reinforcement, reinforced concrete beam, shear strength
Procedia PDF Downloads 3314142 Analysis of a Discrete-time Geo/G/1 Queue Integrated with (s, Q) Inventory Policy at a Service Facility
Authors: Akash Verma, Sujit Kumar Samanta
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This study examines a discrete-time Geo/G/1 queueing-inventory system attached with (s, Q) inventory policy. Assume that the customers follow the Bernoulli process on arrival. Each customer demands a single item with arbitrarily distributed service time. The inventory is replenished by an outside supplier, and the lead time for the replenishment is determined by a geometric distribution. There is a single server and infinite waiting space in this facility. Demands must wait in the specified waiting area during a stock-out period. The customers are served on a first-come-first-served basis. With the help of the embedded Markov chain technique, we determine the joint probability distributions of the number of customers in the system and the number of items in stock at the post-departure epoch using the Matrix Analytic approach. We relate the system length distribution at post-departure and outside observer's epochs to determine the joint probability distribution at the outside observer's epoch. We use probability distributions at random epochs to determine the waiting time distribution. We obtain the performance measures to construct the cost function. The optimum values of the order quantity and reordering point are found numerically for the variety of model parameters.Keywords: discrete-time queueing inventory model, matrix analytic method, waiting-time analysis, cost optimization
Procedia PDF Downloads 444141 Benefits of Hybrid Mix in Renewable Energy and Integration with E-Efficient Compositions
Authors: Ahmed Khalil
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Increased energy demands around the world have led to the raise in power production which has resulted with more greenhouse gas emissions through fossil sources. These fossil sources and emissions cause deterioration in echo-system. Therefore, renewable energy sources come to the scene as echo-friendly and clean energy sourcing, whereas the electrical devices and energy needs decrease in the timeline. Each of these renewable energy sources contribute to the reduction of greenhouse gases and mitigate environmental deterioration. However, there are also some general and source-specific challenges, which influence the choice of the investors. The most prominent general challenge that effects end-users’ comfort and reliability is usually determined as the intermittence which derives from the diversions of source conditions, due to nature dynamics and uncontrolled periodic changes. Research and development professionals strive to mitigate intermittence challenge through material improvement for each renewable source whereas hybrid source mix stand as a solution. This solution prevails well, when single renewable technologies are upgraded further. On the other hand, integration of energy efficient devices and systems, raise the affirmative effect of such solution in means of less energy requirement in sustainability composition or scenario. This paper provides a glimpse on the advantages of composing renewable source mix versus single usage, with contribution of sampled e-efficient systems and devices. Accordingly it demonstrates the extended benefits, through planning and predictive estimation stages of Ahmadi Town Projects in Kuwait.Keywords: e-efficient systems, hybrid source, intermittence challenge, renewable energy
Procedia PDF Downloads 1364140 Application of Lattice Boltzmann Method to Different Boundary Conditions in a Two Dimensional Enclosure
Authors: Jean Yves Trepanier, Sami Ammar, Sagnik Banik
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Lattice Boltzmann Method has been advantageous in simulating complex boundary conditions and solving for fluid flow parameters by streaming and collision processes. This paper includes the study of three different test cases in a confined domain using the method of the Lattice Boltzmann model. 1. An SRT (Single Relaxation Time) approach in the Lattice Boltzmann model is used to simulate Lid Driven Cavity flow for different Reynolds Number (100, 400 and 1000) with a domain aspect ratio of 1, i.e., square cavity. A moment-based boundary condition is used for more accurate results. 2. A Thermal Lattice BGK (Bhatnagar-Gross-Krook) Model is developed for the Rayleigh Benard convection for both test cases - Horizontal and Vertical Temperature difference, considered separately for a Boussinesq incompressible fluid. The Rayleigh number is varied for both the test cases (10^3 ≤ Ra ≤ 10^6) keeping the Prandtl number at 0.71. A stability criteria with a precise forcing scheme is used for a greater level of accuracy. 3. The phase change problem governed by the heat-conduction equation is studied using the enthalpy based Lattice Boltzmann Model with a single iteration for each time step, thus reducing the computational time. A double distribution function approach with D2Q9 (density) model and D2Q5 (temperature) model are used for two different test cases-the conduction dominated melting and the convection dominated melting. The solidification process is also simulated using the enthalpy based method with a single distribution function using the D2Q5 model to provide a better understanding of the heat transport phenomenon. The domain for the test cases has an aspect ratio of 2 with some exceptions for a square cavity. An approximate velocity scale is chosen to ensure that the simulations are within the incompressible regime. Different parameters like velocities, temperature, Nusselt number, etc. are calculated for a comparative study with the existing works of literature. The simulated results demonstrate excellent agreement with the existing benchmark solution within an error limit of ± 0.05 implicates the viability of this method for complex fluid flow problems.Keywords: BGK, Nusselt, Prandtl, Rayleigh, SRT
Procedia PDF Downloads 1284139 Death Anxiety, Quality of Life, and Self-Esteem of the Elderly in Surat Thani Province, Thailand
Authors: W. Phokhwang-Just, A. Saraketrin, P. Thongpet, J. Udomkitpipat, J. Kaewsakulthong
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The more people get older and live longer, the more health problems they may have. This cross-sectional study aims to study a correlation between death anxiety, quality of life, and self-esteem as well as factors affecting these variables in the elderly living in Surat Thani Province, Thailand. Of 382 elderly people, who were proportionally sampled from 19 districts in Surat Thani Province, 256 (67%) already returned the questionnaires. The Thai version of Templer’s Death Anxiety, Quality of Life (WHO-BREF), and of Rosenberg’s Self-Esteem Questionnaires were employed. The result showed that the samples had a mean age of 72 years old, 53% were female, 62% were married, 61% graduated with primary-school, and 61% had at least one chronic disease Approximately, 19% of them had 3 diseases. The quality of life (QOL), self-esteem (SE), and death anxiety (DA) of samples were in moderate (n= 91, mean = 86.89, SD = 15.47), high (n = 138, mean = 29.33, SD=4.77), and low level (n= 85, mean = 6.23, SD= 3.65), respectively. The QOL was not significantly different between male and female as well as among different marital status. The female elderly had more DA and less SE than male (t= 2.095, df = 83; t =-3.258, df =135, respectively, p < 0.05). The female elderly, who were separated or widow, had a higher level of DA than did the married elderly (LSD: p < 0.05). The married elderly had a higher level of SE than did the separated, widowed (Tukey HSD, LSD: p < 0.05), or single elderly (LSD: p < 0.05). The more diseases the elderly got, the lower level of QOL they had (r = -0.335, p < 0.05). The QOL was significantly correlated with SE (r =0.434, p < 0.05), but not significantly related to DA (r = -0.200, p = 0.069). The lower level of SE the elderly had, the higher level of DA they become (r = -2.71, p < 0.05). In order to promote the QOL, the SE of the elderly should be enhanced. Consequently, the DA can be minimized. Healthcare providers should provide care that promotes QOL, SE, and reduces DA of the elderly, especially those, who are female, single, and separated or widowed as well as those, who have more diseases than the othersKeywords: death anxiety, quality of life, self-esteem, elderly
Procedia PDF Downloads 3094138 Design and Simulation of Step Structure RF MEMS Switch for K Band Applications
Authors: G. K. S. Prakash, Rao K. Srinivasa
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MEMS plays an important role in wide range of applications like biological, automobiles, military and communication engineering. This paper mainly investigates on capacitive shunt RF MEMS switch with low actuation voltage and low insertion losses. To trim the pull-in voltage, a step structure has introduced to trim air gap between the beam and the dielectric layer with that pull in voltage is trim to 2.9 V. The switching time of the proposed switch is 39.1μs, and capacitance ratio is 67. To get more isolation, we have used aluminum nitride as dielectric material instead of silicon nitride (Si₃N₄) and silicon dioxide (SiO₂) because aluminum nitride has high dielectric constant (εᵣ = 9.5) increases the OFF capacitance and eventually increases the isolation of the switch. The results show that the switch is ON state involves return loss (S₁₁) less than -25 dB up to 40 GHz and insertion loss (S₂₁) is more than -1 dB up to 35 GHz. In OFF state switch shows maximum isolation (S₂₁) of -38 dB occurs at a frequency of 25-27 GHz for K band applications.Keywords: RF MEMS, actuation voltage, isolation loss, switches
Procedia PDF Downloads 3624137 Challenges in Early Diagnosis of Enlarged Vestibular Aqueduct (EVA) in Pediatric Population: A Single Case Report
Authors: Asha Manoharan, Sooraj A. O, Anju K. G
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Enlarged vestibular aqueduct (EVA) refers to the presence of congenital sensorineural hearing loss with an enlarged vestibular aqueduct. The Audiological symptoms of EVA are fluctuating and progressive in nature and the diagnosis of EVAS can be confirmed only with radiological evaluation. Hence it is difficult to differentiate EVA from conditions like Meniere’s disease, semi-circular dehiscence, etc based on audiological findings alone. EVA in adults is easy to identify due to distinct vestibular symptoms. In children, EVA can remain either unidentified or misdiagnosed until the vestibular symptoms are evident. Motor developmental delay, especially the ones involving a change of body alignment, has been reported in the pediatric population with EVA. So, it should be made mandatory to recommend radiological evaluation in young children with fluctuating hearing loss reporting with motor developmental delay. This single case study of a baby with Enlarged Vestibular Aqueduct (EVA) primarily aimed to address the following: a) Challenges while diagnosing young patients with EVA and fluctuating hearing loss, b) Importance of radiological evaluation in audiological diagnosis in the pediatric population, c) Need for regular monitoring of hearing, hearing aid performance, and cochlear implant mapping closely for potential fluctuations in such populations, d) Importance of reviewing developmental, language milestones in very young children with fluctuating hearing loss.Keywords: enlarged vestibular aqueduct (EVA), motor delay, radiological evaluation, fluctuating hearing loss, cochlear implant
Procedia PDF Downloads 167