Search results for: calibration method
17805 The Beam Expansion Method, A Simplified and Efficient Approach of Field Propagation and Resonators Modes Study
Authors: Zaia Derrar Kaddour
Abstract:
The study of a beam throughout an optical path is generally achieved by means of diffraction integral. Unfortunately, in some problems, this tool turns out to be not very friendly and hard to implement. Instead, the beam expansion method for computing field profiles appears to be an interesting alternative. The beam expansion method consists of expanding the field pattern as a series expansion in a set of orthogonal functions. Propagating each individual component through a circuit and adding up the derived elements leads easily to the result. The problem is then reduced to finding how the expansion coefficients change in a circuit. The beam expansion method requires a systematic study of each type of optical element that can be met in the considered optical path. In this work, we analyze the following fundamental elements: first order optical systems, hard apertures and waveguides. We show that the former element type is completely defined thanks to the Gouy phase shift expression we provide and the latters require a suitable mode conversion. For endorsing the usefulness and relevance of the beam expansion approach, we show here some of its applications such as the treatment of the thermal lens effect and the study of unstable resonators.Keywords: gouy phase shift, modes, optical resonators, unstable resonators
Procedia PDF Downloads 6417804 Experimental Investigation on Residual Stresses in Welded Medium-Walled I-shaped Sections Fabricated from Q460GJ Structural Steel Plates
Authors: Qian Zhu, Shidong Nie, Bo Yang, Gang Xiong, Guoxin Dai
Abstract:
GJ steel is a new type of high-performance structural steel which has been increasingly adopted in practical engineering. Q460GJ structural steel has a nominal yield strength of 460 MPa, which does not decrease significantly with the increase of steel plate thickness like normal structural steel. Thus, Q460GJ structural steel is normally used in medium-walled welded sections. However, research works on the residual stress in GJ steel members are few though it is one of the vital factors that can affect the member and structural behavior. This article aims to investigate the residual stresses in welded I-shaped sections fabricated from Q460GJ structural steel plates by experimental tests. A total of four full scale welded medium-walled I-shaped sections were tested by sectioning method. Both circular curve correction method and straightening measurement method were adopted in this study to obtain the final magnitude and distribution of the longitudinal residual stresses. In addition, this paper also explores the interaction between flanges and webs. And based on the statistical evaluation of the experimental data, a multilayer residual stress model is proposed.Keywords: Q460GJ structural steel, residual stresses, sectioning method, welded medium-walled I-shaped sections
Procedia PDF Downloads 31917803 Automatic Vehicle Detection Using Circular Synthetic Aperture Radar Image
Authors: Leping Chen, Daoxiang An, Xiaotao Huang
Abstract:
Automatic vehicle detection using synthetic aperture radar (SAR) image has been widely researched, as well as using optical remote sensing images. However, most researches treat the detection as an independent problem, failing to make full use of SAR data information. In circular SAR (CSAR), the two long borders of vehicle will shrink if the imaging surface is set higher than the reference one. Based on above variance, an automatic vehicle detection using CSAR image is proposed to enhance detection ability under complex environment, such as vehicles’ closely packing, which confuses the detector. The detection method uses the multiple images generated by different height plane to obtain an energy-concentrated image for detecting and then uses the maximally stable extremal regions method (MSER) to detect vehicles. A result of vehicles’ detection is given to verify the effectiveness and correctness of proposed method.Keywords: circular SAR, vehicle detection, automatic, imaging
Procedia PDF Downloads 37017802 A Machine Learning Approach for Detecting and Locating Hardware Trojans
Authors: Kaiwen Zheng, Wanting Zhou, Nan Tang, Lei Li, Yuanhang He
Abstract:
The integrated circuit industry has become a cornerstone of the information society, finding widespread application in areas such as industry, communication, medicine, and aerospace. However, with the increasing complexity of integrated circuits, Hardware Trojans (HTs) implanted by attackers have become a significant threat to their security. In this paper, we proposed a hardware trojan detection method for large-scale circuits. As HTs introduce physical characteristic changes such as structure, area, and power consumption as additional redundant circuits, we proposed a machine-learning-based hardware trojan detection method based on the physical characteristics of gate-level netlists. This method transforms the hardware trojan detection problem into a machine-learning binary classification problem based on physical characteristics, greatly improving detection speed. To address the problem of imbalanced data, where the number of pure circuit samples is far less than that of HTs circuit samples, we used the SMOTETomek algorithm to expand the dataset and further improve the performance of the classifier. We used three machine learning algorithms, K-Nearest Neighbors, Random Forest, and Support Vector Machine, to train and validate benchmark circuits on Trust-Hub, and all achieved good results. In our case studies based on AES encryption circuits provided by trust-hub, the test results showed the effectiveness of the proposed method. To further validate the method’s effectiveness for detecting variant HTs, we designed variant HTs using open-source HTs. The proposed method can guarantee robust detection accuracy in the millisecond level detection time for IC, and FPGA design flows and has good detection performance for library variant HTs.Keywords: hardware trojans, physical properties, machine learning, hardware security
Procedia PDF Downloads 14917801 Investigating the Energy Gap and Wavelength of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ Superlattices in Terms of Material Thickness and Al Mole Fraction Using Empirical Tight-Binding Method
Authors: Matineh Sadat Hosseini Gheidari, Vahid Reza Yazdanpanah
Abstract:
In this paper, we used the empirical tight-binding method (ETBM) with sp3s* approximation and considering the first nearest neighbor with spin-orbit interactions in order to model superlattice structure (SLS) of (AlₓGa₁₋ₓAs)ₘ/(GaAs)ₙ grown on GaAs (100) substrate at 300K. In the next step, we investigated the behavior of the energy gap and wavelength of this superlattice in terms of different thicknesses of core materials and Al mole fractions. As a result of this survey, we found out that as the Al composition increases, the energy gap of this superlattice has an upward trend and ranges from 1.42-1.63 eV. Also, according to the wavelength range that we gained from this superlattice in different Al mole fractions and various thicknesses, we can find a suitable semiconductor for a special light-emitting diode (LED) application.Keywords: energy gap, empirical tight-binding method, light-emitting diode, superlattice, wavelength
Procedia PDF Downloads 21217800 Fractional Euler Method and Finite Difference Formula Using Conformable Fractional Derivative
Authors: Ramzi B. Albadarneh
Abstract:
In this paper, we use the new definition of fractional derivative called conformable fractional derivative to derive some finite difference formulas and its error terms which are used to solve fractional differential equations and fractional partial differential equations, also to derive fractional Euler method and its error terms which can be applied to solve fractional differential equations. To provide the contribution of our work some applications on finite difference formulas and Euler Method are given.Keywords: conformable fractional derivative, finite difference formula, fractional derivative, finite difference formula
Procedia PDF Downloads 43917799 Application Reliability Method for Concrete Dams
Authors: Mustapha Kamel Mihoubi, Mohamed Essadik Kerkar
Abstract:
Probabilistic risk analysis models are used to provide a better understanding of the reliability and structural failure of works, including when calculating the stability of large structures to a major risk in the event of an accident or breakdown. This work is interested in the study of the probability of failure of concrete dams through the application of reliability analysis methods including the methods used in engineering. It is in our case, the use of level 2 methods via the study limit state. Hence, the probability of product failures is estimated by analytical methods of the type first order risk method (FORM) and the second order risk method (SORM). By way of comparison, a level three method was used which generates a full analysis of the problem and involves an integration of the probability density function of random variables extended to the field of security using the Monte Carlo simulation method. Taking into account the change in stress following load combinations: normal, exceptional and extreme acting on the dam, calculation of the results obtained have provided acceptable failure probability values which largely corroborate the theory, in fact, the probability of failure tends to increase with increasing load intensities, thus causing a significant decrease in strength, shear forces then induce a shift that threatens the reliability of the structure by intolerable values of the probability of product failures. Especially, in case the increase of uplift in a hypothetical default of the drainage system.Keywords: dam, failure, limit-state, monte-carlo, reliability, probability, simulation, sliding, taylor
Procedia PDF Downloads 32617798 An Improved Circulating Tumor Cells Analysis Method for Identifying Tumorous Blood Cells
Authors: Salvador Garcia Bernal, Chi Zheng, Keqi Zhang, Lei Mao
Abstract:
Circulating Tumor Cells (CTC) is used to detect tumoral cell metastases using blood samples of patients with cancer (lung, breast, etc.). Using an immunofluorescent method a three channel image (Red, Green, and Blue) are obtained. These set of images usually overpass the 11 x 30 M pixels in size. An aided tool is designed for imaging cell analysis to segmented and identify the tumorous cell based on the three markers signals. Our Method, it is cell-based (area and cell shape) considering each channel information and extracting and making decisions if it is a valid CTC. The system also gives information about number and size of tumor cells found in the sample. We present results in real-life samples achieving acceptable performance in identifying CTCs in short time.Keywords: Circulating Tumor Cells (CTC), cell analysis, immunofluorescent, medical image analysis
Procedia PDF Downloads 21517797 Effect of Joule Heating on Chemically Reacting Micropolar Fluid Flow over Truncated Cone with Convective Boundary Condition Using Spectral Quasilinearization Method
Authors: Pradeepa Teegala, Ramreddy Chetteti
Abstract:
This work emphasizes the effects of heat generation/absorption and Joule heating on chemically reacting micropolar fluid flow over a truncated cone with convective boundary condition. For this complex fluid flow problem, the similarity solution does not exist and hence using non-similarity transformations, the governing fluid flow equations along with related boundary conditions are transformed into a set of non-dimensional partial differential equations. Several authors have applied the spectral quasi-linearization method to solve the ordinary differential equations, but here the resulting nonlinear partial differential equations are solved for non-similarity solution by using a recently developed method called the spectral quasi-linearization method (SQLM). Comparison with previously published work on special cases of the problem is performed and found to be in excellent agreement. The influence of pertinent parameters namely Biot number, Joule heating, heat generation/absorption, chemical reaction, micropolar and magnetic field on physical quantities of the flow are displayed through graphs and the salient features are explored in detail. Further, the results are analyzed by comparing with two special cases, namely, vertical plate and full cone wherever possible.Keywords: chemical reaction, convective boundary condition, joule heating, micropolar fluid, spectral quasilinearization method
Procedia PDF Downloads 34817796 The Impact of Cooperative Learning on Numerical Methods Course
Authors: Sara Bilal, Abdi Omar Shuriye, Raihan Othman
Abstract:
Numerical Methods is a course that can be conducted using workshops and group discussion. This study has been implemented on undergraduate students of level two at the Faculty of Engineering, International Islamic University Malaysia. The Numerical Method course has been delivered to two Sections 1 and 2 with 44 and 22 students in each section, respectively. Systematic steps have been followed to apply the student centered learning approach in teaching Numerical Method course. Initially, the instructor has chosen the topic which was Euler’s Method to solve Ordinary Differential Equations (ODE) to be learned. The students were then divided into groups with five members in each group. Initial instructions have been given to the group members to prepare their subtopics before meeting members from other groups to discuss the subtopics in an expert group inside the classroom. For the time assigned for the classroom discussion, the setting of the classroom was rearranged to accommodate the student centered learning approach. Teacher strength was by monitoring the process of learning inside and outside the class. The students have been assessed during the migrating to the expert groups, recording of a video explanation outside the classroom and during the final examination. Euler’s Method to solve the ODE was set as part of Question 3(b) in the final exam. It is observed that none of the students from both sections obtained a zero grade in Q3(b), compared to Q3(a) and Q3(c). Also, for Section 1(44 students), 29 students obtained the full mark of 7/7, while only 10 obtained 7/7 for Q3(a) and no students obtained 6/6 for Q3(c). Finally, we can recommend that the Numerical Method course be moved toward more student-centered Learning classrooms where the students will be engaged in group discussion rather than having a teacher one man show.Keywords: teacher centered learning, student centered learning, mathematic, numerical methods
Procedia PDF Downloads 36817795 Inverse Scattering for a Second-Order Discrete System via Transmission Eigenvalues
Authors: Abdon Choque-Rivero
Abstract:
The Jacobi system with the Dirichlet boundary condition is considered on a half-line lattice when the coefficients are real valued. The inverse problem of recovery of the coefficients from various data sets containing the so-called transmission eigenvalues is analyzed. The Marchenko method is utilized to solve the corresponding inverse problem.Keywords: inverse scattering, discrete system, transmission eigenvalues, Marchenko method
Procedia PDF Downloads 14517794 Development of a Small-Group Teaching Method for Enhancing the Learning of Basic Acupuncture Manipulation Optimized with the Theory of Motor Learning
Authors: Wen-Chao Tang, Tang-Yi Liu, Ming Gao, Gang Xu, Hua-Yuan Yang
Abstract:
This study developed a method for teaching acupuncture manipulation in small groups optimized with the theory of motor learning. Sixty acupuncture students and their teacher participated in our research. Motion videos were recorded of their manipulations using the lifting-thrusting method. These videos were analyzed using Simi Motion software to acquire the movement parameters of the thumb tip. The parameter velocity curves along Y axis was used to generate small teaching groups clustered by a self-organized map (SOM) and K-means. Ten groups were generated. All the targeted instruction based on the comparative results groups as well as the videos of teacher and student was provided to the members of each group respectively. According to the theory and research of motor learning, the factors or technologies such as video instruction, observational learning, external focus and summary feedback were integrated into this teaching method. Such efforts were desired to improve and enhance the effectiveness of current acupuncture teaching methods in limited classroom teaching time and extracurricular training.Keywords: acupuncture, group teaching, video instruction, observational learning, external focus, summary feedback
Procedia PDF Downloads 18217793 Intrusion Detection Techniques in NaaS in the Cloud: A Review
Authors: Rashid Mahmood
Abstract:
The network as a service (NaaS) usage has been well-known from the last few years in the many applications, like mission critical applications. In the NaaS, prevention method is not adequate as the security concerned, so the detection method should be added to the security issues in NaaS. The authentication and encryption are considered the first solution of the NaaS problem whereas now these are not sufficient as NaaS use is increasing. In this paper, we are going to present the concept of intrusion detection and then survey some of major intrusion detection techniques in NaaS and aim to compare in some important fields.Keywords: IDS, cloud, naas, detection
Procedia PDF Downloads 32417792 Analysis of Exponential Nonuniform Transmission Line Parameters
Authors: Mounir Belattar
Abstract:
In this paper the Analysis of voltage waves that propagate along a lossless exponential nonuniform line is presented. For this analysis the parameters of this line are assumed to be varying function of the distance x along the line from the source end. The approach is based on the tow-port networks cascading presentation to derive the ABDC parameters of transmission using Picard-Carson Method which is a powerful method in getting a power series solution for distributed network because it is easy to calculate poles and zeros and solves differential equations such as telegrapher equations by an iterative sequence. So the impedance, admittance voltage and current along the line are expanded as a Taylor series in x/l where l is the total length of the line to obtain at the end, the main transmission line parameters such as voltage response and transmission and reflexion coefficients represented by scattering parameters in frequency domain.Keywords: ABCD parameters, characteristic impedance exponential nonuniform transmission line, Picard-Carson's method, S parameters, Taylor's series
Procedia PDF Downloads 44417791 Determining the Octanol-Water Partition Coefficient for Armchair Polyhex BN Nanotubes Using Topological Indices
Authors: Esmat Mohammadinasab
Abstract:
The aim of this paper is to investigate theoretically and establish a predictive model for determination LogP of armchair polyhex BN nanotubes by using simple descriptors. The relationship between the octanol-water partition coefficient (LogP) and quantum chemical descriptors, electric moments, and topological indices of some armchair polyhex BN nanotubes with various lengths and fixed circumference are represented. Based on density functional theory (DFT) electric moments and physico-chemical properties of those nanotubes are calculated. The DFT method performed based on the Becke’s 3-parameter formulation with the Lee-Yang-Parr functional (B3LYP) method and 3-21G standard basis sets. For the first time, the relationship between partition coefficient and different properties of polyhex BN nanotubes is investigated.Keywords: topological indices, quantum descriptors, DFT method, nanotubes
Procedia PDF Downloads 33817790 Direct Phoenix Identification and Antimicrobial Susceptibility Testing from Positive Blood Culture Broths
Authors: Waad Al Saleemi, Badriya Al Adawi, Zaaima Al Jabri, Sahim Al Ghafri, Jalila Al Hadhramia
Abstract:
Objectives: Using standard lab methods, a positive blood culture requires a minimum of two days (two occasions of overnight incubation) to obtain a final identification (ID) and antimicrobial susceptibility results (AST) report. In this study, we aimed to evaluate the accuracy and precision of identification and antimicrobial susceptibility testing of an alternative method (direct method) that will reduce the turnaround time by 24 hours. This method involves the direct inoculation of positive blood culture broths into the Phoenix system using serum separation tubes (SST). Method: This prospective study included monomicrobial-positive blood cultures obtained from January 2022 to May 2023 in SQUH. Blood cultures containing a mixture of organisms, fungi, or anaerobic organisms were excluded from this study. The result of the new “direct method” under study was compared with the current “standard method” used in the lab. The accuracy and precision were evaluated for the ID and AST using Clinical and Laboratory Standards Institute (CLSI) recommendations. The categorical agreement, essential agreement, and the rates of very major errors (VME), major errors (ME), and minor errors (MIE) for both gram-negative and gram-positive bacteria were calculated. Passing criteria were set according to CLSI. Result: The results of ID and AST were available for a total of 158 isolates. Of 77 isolates of gram-negative bacteria, 71 (92%) were correctly identified at the species level. Of 70 isolates of gram-positive bacteria, 47(67%) isolates were correctly identified. For gram-negative bacteria, the essential agreement of the direct method was ≥92% when compared to the standard method, while the categorical agreement was ≥91% for all tested antibiotics. The precision of ID and AST were noted to be 100% for all tested isolates. For gram-positive bacteria, the essential agreement was >93%, while the categorical agreement was >92% for all tested antibiotics except moxifloxacin. Many antibiotics were noted to have an unacceptable higher rate of very major errors including penicillin, cotrimoxazole, clindamycin, ciprofloxacin, and moxifloxacin. However, no error was observed in the results of vancomycin, linezolid, and daptomycin. Conclusion: The direct method of ID and AST for positive blood cultures using SST is reliable for gram negative bacteria. It will significantly decrease the turnaround time and will facilitate antimicrobial stewardship.Keywords: bloodstream infection, oman, direct ast, blood culture, rapid identification, antimicrobial susceptibility, phoenix, direct inoculation
Procedia PDF Downloads 6717789 Hydrological Method to Evaluate Environmental Flow: Case Study of Gharasou River, Ardabil
Authors: Mehdi Fuladipanah, Mehdi Jorabloo
Abstract:
Water flow management is one of the most important parts of river engineering. Non-uniformity distribution of rainfall and various flow demand with unreasonable flow management will be caused destroyed of the river ecosystem. Then, it is severe to determine ecosystem flow requirement. In this paper, Flow duration curve indices method which has hydrological based was used to evaluate environmental flow in Gharasou River, Ardabil, Iran. Using flow duration curve, Q90 and Q95 for different return periods were calculated. Their magnitude was determined as 1-day, 3-day, 7-day, and 30 days. According to the second method, hydraulic alteration indices often had low and medium range. To maintain river at an acceptable ecological condition, minimum daily discharge of index Q95 is 0.7 m^3.s^-1.Keywords: Gharasou River, water flow management, non-uniformity distribution, ecosystem flow requirement, hydraulic alteration
Procedia PDF Downloads 33717788 Trajectory Tracking Controller Based on Normalized Right Coprime Factorization Technique for the Ball and Plate System
Authors: Martins Olatunbosun Babatunde, Muhammed Bashir Muazu, Emmanuel Adewale Adedokun
Abstract:
This paper presents the development of a double-loop trajectory-tracking controller for the ball and plate system (BPS) using the Normalized Right Coprime Factorization (NRCF) scheme.The Linear Algebraic (LA) method is used to design the inner loop required to stabilize the ball, while H-infinity NRCF method, that involved the lead-lag compensator design approach, is used to develop the outer loop that controls the plate. Simulation results show that the plate was stabilized at 0.2989 seconds and the ball was able to settle after 0.9646 seconds, with a trajectory tracking error of 0.0036. This shows that the controller has good adaptability and robustness.Keywords: ball and plate system, normalized right coprime factorization, linear algebraic method, compensator, controller, tracking.
Procedia PDF Downloads 14317787 Detection and Classification of Myocardial Infarction Using New Extracted Features from Standard 12-Lead ECG Signals
Authors: Naser Safdarian, Nader Jafarnia Dabanloo
Abstract:
In this paper we used four features i.e. Q-wave integral, QRS complex integral, T-wave integral and total integral as extracted feature from normal and patient ECG signals to detection and localization of myocardial infarction (MI) in left ventricle of heart. In our research we focused on detection and localization of MI in standard ECG. We use the Q-wave integral and T-wave integral because this feature is important impression in detection of MI. We used some pattern recognition method such as Artificial Neural Network (ANN) to detect and localize the MI. Because these methods have good accuracy for classification of normal and abnormal signals. We used one type of Radial Basis Function (RBF) that called Probabilistic Neural Network (PNN) because of its nonlinearity property, and used other classifier such as k-Nearest Neighbors (KNN), Multilayer Perceptron (MLP) and Naive Bayes Classification. We used PhysioNet database as our training and test data. We reached over 80% for accuracy in test data for localization and over 95% for detection of MI. Main advantages of our method are simplicity and its good accuracy. Also we can improve accuracy of classification by adding more features in this method. A simple method based on using only four features which extracted from standard ECG is presented which has good accuracy in MI localization.Keywords: ECG signal processing, myocardial infarction, features extraction, pattern recognition
Procedia PDF Downloads 45817786 Faults Diagnosis by Thresholding and Decision tree with Neuro-Fuzzy System
Authors: Y. Kourd, D. Lefebvre
Abstract:
The monitoring of industrial processes is required to ensure operating conditions of industrial systems through automatic detection and isolation of faults. This paper proposes a method of fault diagnosis based on a neuro-fuzzy hybrid structure. This hybrid structure combines the selection of threshold and decision tree. The validation of this method is obtained with the DAMADICS benchmark. In the first phase of the method, a model will be constructed that represents the normal state of the system to fault detection. Signatures of the faults are obtained with residuals analysis and selection of appropriate thresholds. These signatures provide groups of non-separable faults. In the second phase, we build faulty models to see the flaws in the system that cannot be isolated in the first phase. In the latest phase we construct the tree that isolates these faults.Keywords: decision tree, residuals analysis, ANFIS, fault diagnosis
Procedia PDF Downloads 62817785 Adopted Method of Information System Strategy for Knowledge Management System: A Literature Review
Authors: Elin Cahyaningsih, Dana Indra Sensuse, Wahyu Catur Wibowo, Sofiyanti Indriasari
Abstract:
Bureaucracy reform program drives Indonesian government to change their management and supporting unit in order to enhance their organization performance. Information technology as one of supporting unit became one of strategic plan that organization tried to improve, because IT can automate and speed up process, reduce business process life cycle become more effective and efficient. Knowledge management system is a technology application for supporting knowledge management implementation in government which is requirement based on problem and potential functionality of each knowledge management process. Define knowledge management that suitable for each organization it is difficult, that why we should make the knowledge management system strategy as an alignment of knowledge management process in the organization. Knowledge management system is one of information system development in people perspective, because this system has high dependency in human interaction and participation. Strategic plan for developing knowledge management system can be determine using some of information system strategic methods. This research conducted to define type of strategic method of information system, stage of activity each method, the strategic method strength and weakness. The author use literature review methods for identify and classify strategic methods of information system for differentiate method type, categorize common activities, strength and weakness. Result of this research are determine and compare six strategic information system methods, there are Balanced Scorecard, Five Force Porter, SWOT analysis, Value Chain Analysis, Risk Analysis and Gap Analysis. Balanced Scorecard and Risk Analysis believe as common strategic method that usually used and have the highest excellence strength.Keywords: knowledge management system, balanced scorecard, five force, risk analysis, gap analysis, value chain analysis, SWOT analysis
Procedia PDF Downloads 48117784 Real-Time Adaptive Obstacle Avoidance with DS Method and the Influence of Dynamic Environments Change on Different DS
Authors: Saeed Mahjoub Moghadas, Farhad Asadi, Shahed Torkamandi, Hassan Moradi, Mahmood Purgamshidian
Abstract:
In this paper, we present real-time obstacle avoidance approach for both autonomous and non-autonomous DS-based controllers and also based on dynamical systems (DS) method. In this approach, we can modulate the original dynamics of the controller and it allows us to determine safety margin and different types of DS to increase the robot’s reactiveness in the face of uncertainty in the localization of the obstacle and especially when robot moves very fast in changeable complex environments. The method is validated in simulation and influence of different autonomous and non-autonomous DS such as limit cycles, and unstable DS on this algorithm and also the position of different obstacles in complex environment is explained. Finally, we describe how the avoidance trajectories can be verified through different parameters such as safety factor.Keywords: limit cycles, nonlinear dynamical system, real time obstacle avoidance, DS-based controllers
Procedia PDF Downloads 39017783 An Image Enhancement Method Based on Curvelet Transform for CBCT-Images
Authors: Shahriar Farzam, Maryam Rastgarpour
Abstract:
Image denoising plays extremely important role in digital image processing. Enhancement of clinical image research based on Curvelet has been developed rapidly in recent years. In this paper, we present a method for image contrast enhancement for cone beam CT (CBCT) images based on fast discrete curvelet transforms (FDCT) that work through Unequally Spaced Fast Fourier Transform (USFFT). These transforms return a table of Curvelet transform coefficients indexed by a scale parameter, an orientation and a spatial location. Accordingly, the coefficients obtained from FDCT-USFFT can be modified in order to enhance contrast in an image. Our proposed method first uses a two-dimensional mathematical transform, namely the FDCT through unequal-space fast Fourier transform on input image and then applies thresholding on coefficients of Curvelet to enhance the CBCT images. Consequently, applying unequal-space fast Fourier Transform leads to an accurate reconstruction of the image with high resolution. The experimental results indicate the performance of the proposed method is superior to the existing ones in terms of Peak Signal to Noise Ratio (PSNR) and Effective Measure of Enhancement (EME).Keywords: curvelet transform, CBCT, image enhancement, image denoising
Procedia PDF Downloads 30217782 The Impact of Artificial Intelligence on Spare Parts Technology
Authors: Amir Andria Gad Shehata
Abstract:
Minimizing the inventory cost, optimizing the inventory quantities, and increasing system operational availability are the main motivations to enhance forecasting demand of spare parts in a major power utility company in Medina. This paper reports in an effort made to optimize the orders quantities of spare parts by improving the method of forecasting the demand. The study focuses on equipment that has frequent spare parts purchase orders with uncertain demand. The pattern of the demand considers a lumpy pattern which makes conventional forecasting methods less effective. A comparison was made by benchmarking various methods of forecasting based on experts’ criteria to select the most suitable method for the case study. Three actual data sets were used to make the forecast in this case study. Two neural networks (NN) approaches were utilized and compared, namely long short-term memory (LSTM) and multilayer perceptron (MLP). The results as expected, showed that the NN models gave better results than traditional forecasting method (judgmental method). In addition, the LSTM model had a higher predictive accuracy than the MLP model.Keywords: spare part, spare part inventory, inventory model, optimization, maintenanceneural network, LSTM, MLP, forecasting demand, inventory management
Procedia PDF Downloads 6617781 Carbon Supported Cu and TiO2 Catalysts Applied for Ozone Decomposition
Authors: Katya Milenova, Penko Nikolov, Irina Stambolova, Plamen Nikolov, Vladimir Blaskov
Abstract:
In the recent article, a comparison was made between Cu and TiO2 supported catalysts on activated carbon for ozone decomposition reaction. The activated carbon support in the case of TiO2/AC sample was prepared by physicochemical pyrolysis and for Cu/AC samples the supports are chemically modified carbons. The prepared catalysts were synthesized by impregnation method. The samples were annealed in two different regimes-in air and under vacuum. To examine adsorption efficiency of the samples BET method was used. All investigated catalysts supported on chemically modified carbons have higher specific surface area compared to the specific surface area of TiO2 supported catalysts, varying in the range 590÷620 m2/g. The method of synthesis of the precursors had influenced catalytic activity.Keywords: activated carbon, adsorption, copper, ozone decomposition, TiO2
Procedia PDF Downloads 41917780 Classifying ERP Implementation’s Risks in Banking Sectors Based on Different Implementation Phases
Authors: Farnaz Farzadnia, Ahmad Alibabaei
Abstract:
Enterprise Resource Planning (ERP) systems are considered as complicated information systems. Many organizations failed implementing ERP systems because it is a very difficult, time-consuming and expensive process. Enterprise resource planning system is appropriate for organizations in all economic sectors. As banking is currently considered a non-typical area for ERP usage, there are very little studies on ERP implementation in banking. This paper presents a general risks taxonomy. In this research, after identifying implementation risks, a process quality management method has been applied to identify relations between risks of implementation ERP in banking sectors and implementation phases. Oracle application implementation method titled as AIM used in this research for classifying the risks. These findings will help managers to develop better strategies for supervising and controlling ERP implementation projects.Keywords: AIM implementation, bank, enterprise resource planning, risk, process quality management method
Procedia PDF Downloads 54817779 Thermo-Aeraulic Studies of a Multizone Building Influence of the Compactness Index
Authors: S. M. A. Bekkouche, T. Benouaz, M. K. Cherier, M. Hamdani, M. R. Yaiche, N. Benamrane
Abstract:
Most codes of building energy simulation neglect the humidity or well represent it with a very simplified method. It is for this reason that we have developed a new approach to the description and modeling of multizone buildings in Saharan climate. The thermal nodal method was used to apprehend thermoaeraulic behavior of air subjected to varied solicitations. In this contribution, analyzing the building geometry introduced the concept of index compactness as "quotient of external walls area and volume of the building". Physical phenomena that we have described in this paper, allow to build the model of the coupled thermoaeraulic behavior. The comparison shows that the found results are to some extent satisfactory. The result proves that temperature and specific humidity depending on compactness and geometric shape. Proper use of compactness index and building geometry parameters will noticeably minimize building energy.Keywords: multizone model, nodal method, compactness index, specific humidity, temperature
Procedia PDF Downloads 41117778 Effective Editable Emoticon Description Schema for Mobile Applications
Authors: Jiwon Lee, Si-hwan Jang, Sanghyun Joo
Abstract:
The popularity of emoticons are on the rise since the mobile messengers are generalized. At the same time, few problems of emoticons are also occurred due to innate characteristics of emoticons. Too many emoticons make difficult people to select one which is well-suited for user's intention. On the contrary to this, sometimes user cannot find the emoticon which expresses user's exact intention. Poor information delivery of emoticon is another problem due to a major part of current emoticons are focused on emotion delivery. In this situation, we propose a new concept of emoticons, editable emoticons, to solve above drawbacks of emoticons. User can edit the components inside the proposed editable emoticon and send it to express his exact intention. By doing so, the number of editable emoticons can be maintained reasonable, and it can express user's exact intention. Further, editable emoticons can be used as information deliverer according to user's intention and editing skills. In this paper, we propose the concept of editable emoticons and schema based editable emoticon description method. The proposed description method is 200 times superior to the compared screen capturing method in the view of transmission bandwidth. Further, the description method is designed to have compatibility since it follows MPEG-UD international standard. The proposed editable emoticons can be exploited not only mobile applications, but also various fields such as education and medical field.Keywords: description schema, editable emoticon, emoticon transmission, mobile applications
Procedia PDF Downloads 29817777 Human Action Recognition Using Variational Bayesian HMM with Dirichlet Process Mixture of Gaussian Wishart Emission Model
Authors: Wanhyun Cho, Soonja Kang, Sangkyoon Kim, Soonyoung Park
Abstract:
In this paper, we present the human action recognition method using the variational Bayesian HMM with the Dirichlet process mixture (DPM) of the Gaussian-Wishart emission model (GWEM). First, we define the Bayesian HMM based on the Dirichlet process, which allows an infinite number of Gaussian-Wishart components to support continuous emission observations. Second, we have considered an efficient variational Bayesian inference method that can be applied to drive the posterior distribution of hidden variables and model parameters for the proposed model based on training data. And then we have derived the predictive distribution that may be used to classify new action. Third, the paper proposes a process of extracting appropriate spatial-temporal feature vectors that can be used to recognize a wide range of human behaviors from input video image. Finally, we have conducted experiments that can evaluate the performance of the proposed method. The experimental results show that the method presented is more efficient with human action recognition than existing methods.Keywords: human action recognition, Bayesian HMM, Dirichlet process mixture model, Gaussian-Wishart emission model, Variational Bayesian inference, prior distribution and approximate posterior distribution, KTH dataset
Procedia PDF Downloads 35617776 Inversion of Electrical Resistivity Data: A Review
Authors: Shrey Sharma, Gunjan Kumar Verma
Abstract:
High density electrical prospecting has been widely used in groundwater investigation, civil engineering and environmental survey. For efficient inversion, the forward modeling routine, sensitivity calculation, and inversion algorithm must be efficient. This paper attempts to provide a brief summary of the past and ongoing developments of the method. It includes reviews of the procedures used for data acquisition, processing and inversion of electrical resistivity data based on compilation of academic literature. In recent times there had been a significant evolution in field survey designs and data inversion techniques for the resistivity method. In general 2-D inversion for resistivity data is carried out using the linearized least-square method with the local optimization technique .Multi-electrode and multi-channel systems have made it possible to conduct large 2-D, 3-D and even 4-D surveys efficiently to resolve complex geological structures that were not possible with traditional 1-D surveys. 3-D surveys play an increasingly important role in very complex areas where 2-D models suffer from artifacts due to off-line structures. Continued developments in computation technology, as well as fast data inversion techniques and software, have made it possible to use optimization techniques to obtain model parameters to a higher accuracy. A brief discussion on the limitations of the electrical resistivity method has also been presented.Keywords: inversion, limitations, optimization, resistivity
Procedia PDF Downloads 367