Search results for: Amir Mehrkar
299 The Impact of COVID-19 on Antibiotic Prescribing in Primary Care in England: Evaluation and Risk Prediction of the Appropriateness of Type and Repeat Prescribing
Authors: Xiaomin Zhong, Alexander Pate, Ya-Ting Yang, Ali Fahmi, Darren M. Ashcroft, Ben Goldacre, Brian Mackenna, Amir Mehrkar, Sebastian C. J. Bacon, Jon Massey, Louis Fisher, Peter Inglesby, Kieran Hand, Tjeerd van Staa, Victoria Palin
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Background: This study aimed to predict risks of potentially inappropriate antibiotic type and repeat prescribing and assess changes during COVID-19. Methods: With the approval of NHS England, we used the OpenSAFELY platform to access the TPP SystmOne electronic health record (EHR) system and selected patients prescribed antibiotics from 2019 to 2021. Multinomial logistic regression models predicted the patient’s probability of receiving an inappropriate antibiotic type or repeating the antibiotic course for each common infection. Findings: The population included 9.1 million patients with 29.2 million antibiotic prescriptions. 29.1% of prescriptions were identified as repeat prescribing. Those with same-day incident infection coded in the EHR had considerably lower rates of repeat prescribing (18.0%), and 8.6% had a potentially inappropriate type. No major changes in the rates of repeat antibiotic prescribing during COVID-19 were found. In the ten risk prediction models, good levels of calibration and moderate levels of discrimination were found. Important predictors included age, prior antibiotic prescribing, and region. Patients varied in their predicted risks. For sore throat, the range from 2.5 to 97.5th percentile was 2.7 to 23.5% (inappropriate type) and 6.0 to 27.2% (repeat prescription). For otitis externa, these numbers were 25.9 to 63.9% and 8.5 to 37.1%, respectively. Interpretation: Our study found no evidence of changes in the level of inappropriate or repeat antibiotic prescribing after the start of COVID-19. Repeat antibiotic prescribing was frequent and varied according to regional and patient characteristics. There is a need for treatment guidelines to be developed around antibiotic failure and clinicians provided with individualised patient information.Keywords: antibiotics, infection, COVID-19 pandemic, antibiotic stewardship, primary care
Procedia PDF Downloads 118298 Analysis of Hydraulic Velocity in Fishway Using CCHE2D Model
Authors: Amir Abbas Kamanbedast, Masood Mohammad Shafipor, Amir Ghotboddin
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Fish way is a structure that in generally using to migrate to the place where they are spawned and is made near the spillway. Preventing fish spawning or migrating to their original place by fishway structures can affect their lives in the river or even erase one access to intended environment. The main objective of these structures is establishing a safe path for fish migration. In the present study first the hydraulic specifications of Hamidieh diversion dam were assessed and then it is problems were evaluated. In this study the dimensions of the fish way, including velocity of pools, were evaluated by CCHE2D software. Then by change slope in this structure streamlines like velocity in the pools were measured. For calibration can be use measuring local velocities in some pools. The information can be seen the fishway width of 0.3 m has minimum rate of descent in the total number of structures (pools and overflow).Keywords: fishway, velocity, Hamidieh-Diversion Dam, CCHE2D model
Procedia PDF Downloads 490297 Comparative Analysis of Traditional and Modern Roundabouts Using Sidra Intersection
Authors: Amir Mohammad Parvini, Amir Masoud Rahimi
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Currently, most parts of the world have shifted from traditional roundabouts to modern roundabouts with respect to the role of roundabouts in reducing accidents, increasing safety, lowering the maintenance costs compared to traffic circles with their improper functional and safety experiences. In this study, field data collected from a current traditional roundabout was analyzed by the software AIMSUN and the obtained numbers were recorded. The modern roundabout was designed by changes in the traditional one, considering the geometric standards listed in regulations. Then, the modern roundabout was analyzed by applying a heterogeneous traffic by a micro-simulation software SIDRA (5.1). The function, capacity, and safety of the roundabout were analyzed assuming the superiority of modern roundabouts and acceptable LOS. The obtained results indicate that the function, capacity, and safety of modern roundabouts are better than traditional ones.Keywords: traditional roundabout, traffic circles, modern roundabout, AIMSUN, SIDRA
Procedia PDF Downloads 397296 Political Cinema: Rewriting The Malaysian Political History Through Documentary Films
Authors: Raja Rodziah Binti Raja Zainal Hassan
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The development of Malaysian political cinema is rapidly taking shape in the local film industry. The paper focuses on the production of independent political documentary by two Malaysian filmmakers, Amir Muhammad and Fahmi Reza. Revolutionary cinema can be understood by utilizing the Third Cinema Theory in order to analyse the meaning and its impact on the audience. The issue surrounding the political cinema in Malaysia is the question of national identity. The implementation of racial or ethnic based politics has resulted in hostility within Malaysia’s multiracial society. Amir Muhammad and Fahmi Reza revisit the Malaysian political history through their films in order to understand the reasons behind the hostility and conflict.Keywords: Political cinema, third cinema theory, revolutionary cinema, national identity, racial or ethnic politics
Procedia PDF Downloads 431295 Alternator Fault Detection Using Wigner-Ville Distribution
Authors: Amin Ranjbar, Amir Arsalan Jalili Zolfaghari, Amir Abolfazl Suratgar, Mehrdad Khajavi
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This paper describes two stages of learning-based fault detection procedure in alternators. The procedure consists of three states of machine condition namely shortened brush, high impedance relay and maintaining a healthy condition in the alternator. The fault detection algorithm uses Wigner-Ville distribution as a feature extractor and also appropriate feature classifier. In this work, ANN (Artificial Neural Network) and also SVM (support vector machine) were compared to determine more suitable performance evaluated by the mean squared of errors criteria. Modules work together to detect possible faulty conditions of machines working. To test the method performance, a signal database is prepared by making different conditions on a laboratory setup. Therefore, it seems by implementing this method, satisfactory results are achieved.Keywords: alternator, artificial neural network, support vector machine, time-frequency analysis, Wigner-Ville distribution
Procedia PDF Downloads 370294 CT Medical Images Denoising Based on New Wavelet Thresholding Compared with Curvelet and Contourlet
Authors: Amir Moslemi, Amir movafeghi, Shahab Moradi
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One of the most important challenging factors in medical images is nominated as noise.Image denoising refers to the improvement of a digital medical image that has been infected by Additive White Gaussian Noise (AWGN). The digital medical image or video can be affected by different types of noises. They are impulse noise, Poisson noise and AWGN. Computed tomography (CT) images are subjected to low quality due to the noise. The quality of CT images is dependent on the absorbed dose to patients directly in such a way that increase in absorbed radiation, consequently absorbed dose to patients (ADP), enhances the CT images quality. In this manner, noise reduction techniques on the purpose of images quality enhancement exposing no excess radiation to patients is one the challenging problems for CT images processing. In this work, noise reduction in CT images was performed using two different directional 2 dimensional (2D) transformations; i.e., Curvelet and Contourlet and Discrete wavelet transform(DWT) thresholding methods of BayesShrink and AdaptShrink, compared to each other and we proposed a new threshold in wavelet domain for not only noise reduction but also edge retaining, consequently the proposed method retains the modified coefficients significantly that result in good visual quality. Data evaluations were accomplished by using two criterions; namely, peak signal to noise ratio (PSNR) and Structure similarity (Ssim).Keywords: computed tomography (CT), noise reduction, curve-let, contour-let, signal to noise peak-peak ratio (PSNR), structure similarity (Ssim), absorbed dose to patient (ADP)
Procedia PDF Downloads 438293 Study on the Stages of Knowledge Flow in Central Libraries of Tehran Universities by the Pattern of American Productivity & Quality Center
Authors: Amir Reza Asnafi, Ehsan Tajabadi, Mohsen Hajizeinolabedini
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The purpose of this study is to identify the concept of knowledge flow in central libraries of Tehran universities in by the pattern of American Productivity & Quality Center (APQC). The present study is an applied and descriptive survey in terms of its purpose and the methodology used. In this study, APQC framework was used for data collection. The study population is managers and supervisors of central libraries’ departments of public universities of Tehran belonging to the Ministry of Science, Research and Technology. These libraries include: Central Libraries of Al-Zahra University, Amir Kabir, Tarbiat Modarres, Tehran, Khajeh Nasir Toosi University of Technology, Shahed, Sharif, Shahid Beheshti, Allameh Tabataba'i University, Iran University of Science and Technology. Due to the limited number of members of the community, sampling was not performed and the census was conducted instead. The study of knowledge flow in central libraries of public universities in Tehran showed that in seven dimensions of knowledge flow of APQC, these libraries are far from desirable level and to achieve the ideal point, many activities in the field of knowledge flow need to be made, therefore suggestions were made in this study to reach the desired level. One Sample t Test in this research showed that these libraries are at a poor level in terms of these factors: in the dimensions of creation, identification and use of knowledge at a medium level and in the aspects of knowledge acquisition, review, sharing and access and also Manova test or Multivariable Analyze of Variance proved that there was no significant difference between the dimensions of knowledge flow between these libraries and the status of the knowledge flow in these libraries is at the same level as well. Except for the knowledge creation aspect that is slightly different in this regard that was mentioned before.Keywords: knowledge flow, knowledge management, APQC, Tehran’s academic university libraries
Procedia PDF Downloads 161292 Blockchain Solutions for IoT Challenges: Overview
Authors: Amir Ali Fatoorchi
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Regardless of the advantage of LoT devices, they have limitations like storage, compute, and security problems. In recent years, a lot of Blockchain-based research in IoT published and presented. In this paper, we present the Security issues of LoT. IoT has three levels of security issues: Low-level, Intermediate-level, and High-level. We survey and compare blockchain-based solutions for high-level security issues and show how the underlying technology of bitcoin and Ethereum could solve IoT problems.Keywords: Blockchain, security, data security, IoT
Procedia PDF Downloads 208291 Economics of Oil and Its Stability in the Gulf Region
Authors: Al Mutawa A. Amir, Liaqat Ali, Faisal Ali
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After the World War II, the world economy was disrupted and changed due to oil and its prices. The research in this paper presents the basic statistical features and economic characteristics of the Gulf economy. The main features of the Gulf economies and its heavy dependence on oil exports, its dualism between modern and traditional sectors and its rapidly increasing affluences are particularly emphasized. In this context, the research in this paper discussed the problems of growth versus development and has attempted to draw the implications for the future economic development of this area.Keywords: oil prices, GCC, economic growth, gulf oil
Procedia PDF Downloads 333290 Management Trainee Program
Authors: Ambreen Amir Ali
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In todays’ dynamic environment, it has become very crucial to have comprehensive management trainee program to hire future leaders of organization. It is being proved that fresh graduates mostly join organizations because of its institution but later on they leave organization because of their immediate manager or supervisor. The concept of coaching and mentoring in talent management systems are very important, because mentors are those who can advise, facilitate, help and support new entrants to advance in their career. When it comes to going for talent hunt, one point needs to be highlighted that MTs are the raw talent for your organization, now it’s the responsibility of employers to nourish them, polish and developed them so that they can enthusiastically take care of senior leadership roles.Keywords: management trainee, retention, leadership roles, coaching
Procedia PDF Downloads 635289 In-Situ Synthesis of Zinc-Containing MCM-41 and Investigation of Its Capacity for Removal of Hydrogen Sulfide from Crude Oil
Authors: Nastaran Hazrati, Ali Akbar Miran Beigi, Majid Abdouss, Amir Vahid
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Hydrogen sulfide is the most toxic gas of crude oil. Adsorption is an energy-efficient process used to remove undesirable compounds such as H2S in gas or liquid streams by passing the stream through a media bed composed of an adsorbent. In this study, H2S of Iran crude oil was separated via cold stripping then zinc incorporated MCM-41 was synthesized via an in-situ method. ZnO functionalized mesoporous silica samples were characterized by XRD, N2 adsorption and TEM. The obtained results of adsorption of H2S showed superior ability of all the materials and with an increase in ZnO amount adsorption was increased.Keywords: MCM-41, ZnO, H2S removal, adsorption
Procedia PDF Downloads 462288 The Grand Unified Theory of Everything as a Generalization to the Standard Model Called as the General Standard Model
Authors: Amir Deljoo
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The endeavor to comprehend the existence have been the center of thought for human in form of different disciplines and now basically in physics as the theory of everything. Here, after a brief review of the basic frameworks of thought, and a history of thought since ancient up to present, a logical methodology is presented based on a core axiom after which a function, a proto-field and then a coordinates are explained. Afterwards a generalization to Standard Model is proposed as General Standard Model which is believed to be the base of the Unified Theory of Everything.Keywords: general relativity, grand unified theory, quantum mechanics, standard model, theory of everything
Procedia PDF Downloads 98287 Investigation of Riprap Stability on Roughness Bridge Pier in River Bend
Authors: A. Alireza Masjedi, B. Amir Taeedi
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In this research, by placing the two cylindrical piers without roughness and with roughness with riprap around its, they proceeded to a series of tests. Experiments were done by three relative diameters of riprap with density 2.1 and one rate of discharge 27 lit/s under pure water condition. In each experiment, flow depth measured in terms of failure threshold then stability number calculated by using data obtained. The results of the research showed that the riprap stability in pier with roughness is more pier without roughness because of the pier with roughness is sharp-pointed and reduced horseshoe vortex.Keywords: riprap stability, roughness, river bend, froude number
Procedia PDF Downloads 351286 Effect of Riprap Stability on Roughness Bridge Pier in River Bend
Authors: Alireza Masjedi, Amir Taeedi
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In this research, by placing the two cylindrical piers without roughness and with roughness with riprap around its, they proceeded to a series of tests. Experiments were done by three relative diameters of riprap with density 2.1 and one rate of discharge 27 lit/s under pure water condition. In each experiment, flow depth measured in terms of failure threshold then stability number calculated by using data obtained. The results of the research showed that the riprap stability in pier with roughness is more pier without roughness because of the pier with roughness is sharp-pointed and reduced horseshoe vortex.Keywords: riprap stability, roughness, river bend, froude number
Procedia PDF Downloads 348285 Differential Transform Method: Some Important Examples
Authors: M. Jamil Amir, Rabia Iqbal, M. Yaseen
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In this paper, we solve some differential equations analytically by using differential transform method. For this purpose, we consider four models of Laplace equation with two Dirichlet and two Neumann boundary conditions and K(2,2) equation and obtain the corresponding exact solutions. The obtained results show the simplicity of the method and massive reduction in calculations when one compares it with other iterative methods, available in literature. It is worth mentioning that here only a few number of iterations are required to reach the closed form solutions as series expansions of some known functions.Keywords: differential transform method, laplace equation, Dirichlet boundary conditions, Neumann boundary conditions
Procedia PDF Downloads 535284 A Word-to-Vector Formulation for Word Representation
Authors: Sandra Rizkallah, Amir F. Atiya
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This work presents a novel word to vector representation that is based on embedding the words into a sphere, whereby the dot product of the corresponding vectors represents the similarity between any two words. Embedding the vectors into a sphere enabled us to take into consideration the antonymity between words, not only the synonymity, because of the suitability to handle the polarity nature of words. For example, a word and its antonym can be represented as a vector and its negative. Moreover, we have managed to extract an adequate vocabulary. The obtained results show that the proposed approach can capture the essence of the language, and can be generalized to estimate a correct similarity of any new pair of words.Keywords: natural language processing, word to vector, text similarity, text mining
Procedia PDF Downloads 273283 Synthesis and Characterisation of Bi-Substituted Magnetite Nanoparticles by Mechanochemical Processing (MCP)
Authors: Morteza Mohri Esfahani, Amir S. H. Rozatian, Morteza Mozaffari
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Single phase magnetite nanoparticles and Bi-substituted ones were prepared by mechanochemical processing (MCP). The effects of Bi-substitution on the structural and magnetic properties of the nanoparticles were studied by X-ray Diffraction (XRD) and magnetometry techniques, respectively. The XRD results showed that all samples have spinel phase and by increasing Bi content, the main diffraction peaks were shifted to higher angles, which means the lattice parameter decreases from 0.843 to 0.838 nm and then increases to 0.841 nm. Also, the results revealed that increasing Bi content lead to a decrease in saturation magnetization (Ms) from 74.9 to 48.8 emu/g and an increase in coercivity (Hc) from 96.8 to 137.1 Oe.Keywords: bi-substituted magnetite nanoparticles, mechanochemical processing, X-ray diffraction, magnetism
Procedia PDF Downloads 534282 Effect of Adverse Pressure Gradient on a Fluctuating Velocity over the Co-Flow Jet Airfoil
Authors: Morteza Mirhosseini, Amir B. Khoshnevis
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The boundary layer separation and new active flow control of a NACA 0025 airfoil were studied experimentally. This new flow control is sometimes known as a co-flow jet (cfj) airfoil. This paper presents the fluctuating velocity in a wall jet over the co-flow jet airfoil subjected to an adverse pressure gradient and a curved surface. In these results, the fluctuating velocity at the inner part increasing by increased the angle of attack up to 12o and this has due to the jet energized, while the angle of attack 20o has different. The airfoil cord based Reynolds number has 105.Keywords: adverse pressure gradient, fluctuating velocity, wall jet, co-flow jet airfoil
Procedia PDF Downloads 489281 Isotherm Study of Modified Zeolite in Sorption of Naphthalene from Water Sample
Authors: Homayon Ahmad Panahi, Amir Hesam Hassani, Akram Torki, Elham Moniri
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A new sorbent was synthesized through chemical modification of clinoptilolite zeolite using 2-naphtol, and characterized with fourier transform infrared spectroscopy and elemental analysis methods and applied for the removal and elimination of trace naphthalene from water samples. The optimum pH value for sorption of the naphthalene by modified zeolite was in acidic pH. The sorption capacity of modified zeolite was 142 mg. g−1. Isotherm models, Langmuir, Frendlich and Temkin were employed to analyze the adsorption capacity of modified zeolite, which revealed that naphthalene adsorption by this zeolite follows Langmuir model.Keywords: zeolite, clinoptilolite, modification, naphthalene
Procedia PDF Downloads 487280 Short-Long Term between Gross Domestic Product and Consumption in Indonesia
Authors: Teguh Sugiarto, Ahmad Subagyo, Ludiro Madu, Amir Mohammadian Amiri
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Recently, the significant fluctuations accosiated with Indonesian economy justifies the need for paying more attention to this issue. In this regard, the main objective of this study is to investigate the relationship between two issues related to the macro Indonesia economy called consumption and GDP during the period of 1967 to 2014. This research method exploits short term and long term relationships using Granger and subsequently, models them by the causality method . However, using analysis of Granger with Johansen shows that there is not only a long term, but also a short-long relationship between GDP and consumption using lags the interval 5.Keywords: cointegration, Granger causality, GDP, consumption
Procedia PDF Downloads 355279 Low Power, Highly Linear, Wideband LNA in Wireless SOC
Authors: Amir Mahdavi
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In this paper a highly linear CMOS low noise amplifier (LNA) for ultra-wideband (UWB) applications is proposed. The proposed LNA uses a linearization technique to improve second and third-order intercept points (IIP3). The linearity is cured by repealing the common-mode section of all intermodulation components from the cascade topology current with optimization of biasing current use symmetrical and asymmetrical circuits for biasing. Simulation results show that maximum gain and noise figure are 6.9dB and 3.03-4.1dB over a 3.1–10.6 GHz, respectively. Power consumption of the LNA core and IIP3 are 2.64 mW and +4.9dBm respectively. The wideband input impedance matching of LNA is obtained by employing a degenerating inductor (|S11|<-9.1 dB). The circuit proposed UWB LNA is implemented using 0.18 μm based CMOS technology.Keywords: highly linear LNA, low-power LNA, optimal bias techniques
Procedia PDF Downloads 278278 Improvement a Lower Bound of Energy for Some Family of Graphs, Related to Determinant of Adjacency Matrix
Authors: Saieed Akbari, Yousef Bagheri, Amir Hossein Ghodrati, Sima Saadat Akhtar
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Let G be a simple graph with the vertex set V (G) and with the adjacency matrix A (G). The energy E (G) of G is defined to be the sum of the absolute values of all eigenvalues of A (G). Also let n and m be number of edges and vertices of the graph respectively. A regular graph is a graph where each vertex has the same number of neighbours. Given a graph G, its line graph L(G) is a graph such that each vertex of L(G) represents an edge of G; and two vertices of L(G) are adjacent if and only if their corresponding edges share a common endpoint in G. In this paper we show that for every regular graphs and also for every line graphs such that (G) 3 we have, E(G) 2nm + n 1. Also at the other part of the paper we prove that 2 (G) E(G) for an arbitrary graph G.Keywords: eigenvalues, energy, line graphs, matching number
Procedia PDF Downloads 230277 Output Voltage Analysis of CMOS Colpitts Oscillator with Short Channel Device
Authors: Maryam Ebrahimpour, Amir Ebrahimi
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This paper presents the steady-state amplitude analysis of MOS Colpitts oscillator with short channel device. The proposed method is based on a large signal analysis and the nonlinear differential equations that govern the oscillator circuit behaviour. Also, the short channel effects are considered in the proposed analysis and analytical equations for finding the steady-state oscillation amplitude are derived. The output voltage calculated from this analysis is in excellent agreement with simulations for a wide range of circuit parameters.Keywords: colpitts oscillator, CMOS, electronics, circuits
Procedia PDF Downloads 349276 Consensus-Oriented Analysis Model for Knowledge Management Failure Evaluation in Uncertain Environment
Authors: Amir Ghasem Norouzi, Mahdi Zowghi
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This study propose a framework based on the fuzzy T-Norms, T-conorm, a novel operator, and multi-expert approach to help organizations build awareness of the critical influential factors on the success of knowledge management (KM) implementation, analysis the failure of knowledge management. This study considers the complex uncertainty concept that is in knowledge management implementing capability (KMIC) and it is used by fuzzy logic for this reason. The contribution of our paper is shown with an empirical study in a nonprofit educational organization evaluation.Keywords: fuzzy logic, knowledge management, multi expert analysis, consensus oriented average operator
Procedia PDF Downloads 626275 Flood Scenarios for Hydrological and Hydrodynamic Modelling
Authors: M. Sharif Imam Ibne Amir, Mohammad Masud Kamal Khan, Mohammad Golam Rasul, Raj H. Sharma, Fatema Akram
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Future flood can be predicted using the probable maximum flood (PMF). PMF is calculated using the historical discharge or rainfall data considering the other climatic parameter stationary. However, climate is changing globally and the key climatic variables are temperature, evaporation, rainfall and sea level rise (SLR). To develop scenarios to a basin or catchment scale these important climatic variables should be considered. Nowadays scenario based on climatic variables is more suitable than PMF. Six scenarios were developed for a large Fitzroy basin and presented in this paper.Keywords: climate change, rainfall, potential evaporation, scenario, sea level rise (SLR), sub-catchment
Procedia PDF Downloads 530274 Micro-CT Imaging Of Hard Tissues
Authors: Amir Davood Elmi
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From the earliest light microscope to the most innovative X-ray imaging techniques, all of them have refined and improved our knowledge about the organization and composition of living tissues. The old techniques are time consuming and ultimately destructive to the tissues under the examination. In recent few decades, thanks to the boost of technology, non-destructive visualization techniques, such as X-ray computed tomography (CT), magnetic resonance imaging (MRI), selective plane illumination microscopy (SPIM), and optical projection tomography (OPT), have come to the forefront. Among these techniques, CT is excellent for mineralized tissues such as bone or dentine. In addition, CT it is faster than other aforementioned techniques and the sample remains intact. In this article, applications, advantages, and limitations of micro-CT is discussed, in addition to some information about micro-CT of soft tissue.Keywords: Micro-CT, hard tissue, bone, attenuation coefficient, rapid prototyping
Procedia PDF Downloads 140273 A Hyperexponential Approximation to Finite-Time and Infinite-Time Ruin Probabilities of Compound Poisson Processes
Authors: Amir T. Payandeh Najafabadi
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This article considers the problem of evaluating infinite-time (or finite-time) ruin probability under a given compound Poisson surplus process by approximating the claim size distribution by a finite mixture exponential, say Hyperexponential, distribution. It restates the infinite-time (or finite-time) ruin probability as a solvable ordinary differential equation (or a partial differential equation). Application of our findings has been given through a simulation study.Keywords: ruin probability, compound poisson processes, mixture exponential (hyperexponential) distribution, heavy-tailed distributions
Procedia PDF Downloads 340272 Investigation of the Aerodynamic Characteristics of a Vertical Take-Off and Landing Mini Unmanned Aerial Vehicle Configuration
Authors: Amir Abdelqodus, Mario Shehata
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The purpose of the paper is to model and evaluate the aerodynamic coefficients and stability derivatives of a Vertical, Take-off and Landing Unmanned Aerial Vehicle configuration (VTOL UAV), which is a fixed wing UAV and a quad-copter hybrid capable of both vertical and conventional take-off and/or landing. The aerodynamic analysis of this configuration was carried out using CFD commercial package Ansys Fluent. Also, the aerodynamic coefficients for the case of the UAV without the quad-copter is carried out analytically using MATLAB programmed codes, and the resulting data is verified using Lifting Line Theory and potential method programs. The two results are then compared to understand the effect of adding the quad-copter on the aerodynamic performance of the UAV.Keywords: aerodynamics, CFD, potential flow, UAV, VTOL
Procedia PDF Downloads 443271 Effect of Cloud Computing on Enterprises
Authors: Amir Rashid
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Today is the world of innovations where everyone is looking for a change. Organizations are now looking toward virtualization in order to minimize their computing cost. Cloud Computing has also introduced itself by the means of reducing computing cost. It offers different approach to make computing better by improving utilization and reducing infrastructure and administrative costs. Cloud Computing is basically the amalgamation of Utility Computing and SaaS (Software as a Service). Cloud Computing is quite new to organizations as it is still at its deploying stage. Due to this reason, organizations are not confident whether to adopt it or not. This thesis investigates the problem for organization concerning the security and cost issues. Benefits and drawbacks are being highlighted which organizations can have or suffer in order to adopt Cloud Computing. In Conclusion, Cloud Computing is a better option available for small and medium organizations with a comparison to large companies both in terms of data security and cost.Keywords: cloud computing, security, cost, elasticity, PaaS, IaaS, SaaS
Procedia PDF Downloads 339270 Membranes for Direct Lithium Extraction (DLE)
Authors: Amir Razmjou, Elika Karbassi Yazdi
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Several direct lithium extraction (DLE) technologies have been developed for Li extraction from different brines. Although laboratory studies showed that they can technically recover Li to 90%, challenges still remain in developing a sustainable process that can serve as a foundation for the lithium dependent low-carbon economy. There is a continuing quest for DLE technologies that do not need extensive pre-treatments, fewer materials, and have simplified extraction processes with high Li selectivity. Here, an overview of DLE technologies will be provided with an emphasis on the basic principles of the materials’ design for the development of membranes with nanochannels and nanopores with Li ion selectivity. We have used a variety of building blocks such as nano-clay, organic frameworks, Graphene/oxide, MXene, etc., to fabricate the membranes. Molecular dynamic simulation (MD) and density functional theory (DFT) were used to reveal new mechanisms by which high Li selectivity was obtained.Keywords: lithium recovery, membrane, lithium selectivity, decarbonization
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