Search results for: pinch point analysis
30394 Alternative General Formula to Estimate and Test Influences of Early Diagnosis on Cancer Survival
Authors: Li Yin, Xiaoqin Wang
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Background and purpose: Cancer diagnosis is part of a complex stochastic process, in which patients' personal and social characteristics influence the choice of diagnosing methods, diagnosing methods, in turn, influence the initial assessment of cancer stage, the initial assessment, in turn, influences the choice of treating methods, and treating methods in turn influence cancer outcomes such as cancer survival. To evaluate diagnosing methods, one needs to estimate and test the causal effect of a regime of cancer diagnosis and treatments. Recently, Wang and Yin (Annals of statistics, 2020) derived a new general formula, which expresses these causal effects in terms of the point effects of treatments in single-point causal inference. As a result, it is possible to estimate and test these causal effects via point effects. The purpose of the work is to estimate and test causal effects under various regimes of cancer diagnosis and treatments via point effects. Challenges and solutions: The cancer stage has influences from earlier diagnosis as well as on subsequent treatments. As a consequence, it is highly difficult to estimate and test the causal effects via standard parameters, that is, the conditional survival given all stationary covariates, diagnosing methods, cancer stage and prognosis factors, treating methods. Instead of standard parameters, we use the point effects of cancer diagnosis and treatments to estimate and test causal effects under various regimes of cancer diagnosis and treatments. We are able to use familiar methods in the framework of single-point causal inference to accomplish the task. Achievements: we have applied this method to stomach cancer survival from a clinical study in Sweden. We have studied causal effects under various regimes, including the optimal regime of diagnosis and treatments and the effect moderation of the causal effect by age and gender.Keywords: cancer diagnosis, causal effect, point effect, G-formula, sequential causal effect
Procedia PDF Downloads 19230393 The Feasibility of Economic Science in Islam With an Emphasis on Sadr's Vantage Point
Authors: Yahya Jahangiri, Ali Almasi
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Currently capitalism is one of the most important economic issues discussed by great scholars around the world. But Islamic approach, regarding this issue may differ both western and eastern views. A greatest scholar in Islamic economy ‘especially in Shia’ is Martyr Muhammad Baqir Al-Sadr. He wrote “Our economy” (Iqtisaduna) to present an economic point of view according to the Islamic teachings. In this regard firstly we will mention three approaches which are common in Muslim scullers about the economic science and then the main approach which is Sadr's view is described here. His claim explains that Islam and capitalism are in conflict with each other. And finally he explains the relationship between Islam and economy and he suggests the Islamic point of view in economy and its foundations as a solution for economic problems which we face today.Keywords: Islam, economic science, capitalism, Martyr Sadr
Procedia PDF Downloads 31830392 Characterization of Biodiesel Produced from Cow-Tallow
Authors: Nwadike Emmanuel Chinagoron, Achebe Chukwunonso, Ezeliora Chukwuemeka Daniel, Azaka Onyemazuwa Andrew
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In this research work, the process of biodiesel production in a pilot plant was studied using cow tallow as raw material, methanol as the solvent and potassium hydroxide as catalysts. The biodiesel quality was determined by characterization. The tallow used in the production had a molecular weight of 860g. Its oil had a density value of 0.8g/ml, iodine value of 63.45, viscosity at 300C was 9.83pas, acid value was 1.96, free fatty acid (FFA) of 0.98%, saponification value of 82.75mleq/kg, specific gravity of 0.898, flash point of 1100C, cloud point of 950C and Calorific value also called Higher Heating Value (HHV) of 38.365MJ/Kg. The produced biodiesel had a density of 0.82g/ml, iodine value of 126.9, viscosity of 4.32pas at 300C, acid value of 0.561, FFA of 0.2805%, saponification value of 137.45 mleq/kg.Flash point, cloud point and centane number of the biodiesel produced are 1390C, 980C and 57.5 respectively, with fat content, protein content, ash content, moisture content, fiber content and carbohydrate content values of 10%, 2.8%, 5%, 5%, 20%, and 37.2% respectively. The biodiesel higher heating values (calorific values) when estimated from viscosity, density and flash points were 41.4MJ/Kg, 63.8MJ/Kg, and 34.6MJ/Kg respectively. The biodiesel was blended with conventional diesel. The blend B-10 had values of 1320C and 960C for flash and cloud points, with Calorific value (or HHV) of 34.6 MJ/Kg (when estimated from its Flash point) and fat content, protein content, ash content, moisture content, fiber content and carbohydrate content values of 5%, 2.1%,10%, 5%, 15%, and 62.9% respectively.Keywords: biodiesel, characterization, cow-tallow, cetane rating
Procedia PDF Downloads 52930391 A Research of the Prototype Fuel Injector for the Aircraft Two-Stroke Opposed-Piston Diesel Engine
Authors: Ksenia Siadkowska, Zbigniew Czyz, Lukasz Grabowski
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The paper presents the research results of the construction of an injector with a modified injection nozzle. The injector is designed for a prototype aircraft opposed-piston diesel engine with an assumed starting power of 100 kW. The injector has been subjected to optical tests carried out in a constant volume chamber with the use of a camera allowing to record images at the frequency of 5400 fps and at the resolution of 1024x1024. The measurements were based on a Mie scattering technique with global lighting. Seven repetitions were made for a specific measurement point. The measuring point was selected on the basis of the analysis of engine operating conditions. The analysis focused on the average range of the spray and its distribution. As a result of the conducted research, the range of the fuel spray was defined for the determined parameters of injection. The obtained results were used to verify and optimize the combustion process in the designed opposed-piston two-stroke diesel engine. Acknowledgment: This work has been realized in the cooperation with The Construction Office of WSK 'PZL-KALISZ' S.A.' and is part of Grant Agreement No. POIR.01.02.00-00-0002/15 financed by the Polish National Centre for Research and Development.Keywords: diesel engine, opposed-piston, aircraft, fuel injector
Procedia PDF Downloads 12430390 Stability of the Wellhead in the Seabed in One of the Marine Reservoirs of Iran
Authors: Mahdi Aghaei, Saeid Jamshidi, Mastaneh Hajipour
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Effective factors on the mechanical wellbore stability are divided in to two categories: 1) Controllable factors, 2) Uncontrollable factors. The purpose of geo-mechanical modeling of wells is to determine the limit of controlled parameters change based on the stress regime at each point and by solving the governing equations the pore-elastic environment around the well. In this research, the mechanical analysis of wellbore stability was carried out for Soroush oilfield. For this purpose, the geo-mechanical model of the field is made using available data. This model provides the necessary parameters for obtaining the distribution of stress around the wellbore. Initially, a basic model was designed to perform various analysis, based on obtained data, using Abaqus software. All of the subsequent sensitivity analysis such as sensitivity analysis on porosity, permeability, etc. was done on the same basic model. The results obtained from these analysis gives various result such as: with the constant geomechanical parameters, and sensitivity analysis on porosity permeability is ineffective. After the most important parameters affecting the wellbore stability and instability are geo-mechanical parameters.Keywords: wellbore stability, movement, stress, instability
Procedia PDF Downloads 20030389 Study on Multi-Point Stretch Forming Process for Double Curved Surface
Authors: Jiwoo Park, Junseok Yoon, Jeong Kim, Beomsoo Kang
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Multi-Point Stretch Forming (MPSF) process is suitable for flexible manufacturing, and it has several advantages including that it could be applied to various forming such as sheet metal forming, single curved surface forming and double curved one. In this study, a systematic numerical simulation was carried out for atypical double curved surface forming using the multiple die stretch forming process. In this simulation, urethane pads were defined based on hyper-elastic material model as a cushion for the smooth forming surface. The deformation behaviour on elastic recovery was also investigated to consider the exact result after the last forming process, and then the experiment was also carried out to confirm the formability of this forming process. By comparing the simulation and experiment results, the suitability of the multiple die stretch forming process for the atypical double curved surface was verified. Consequently, it is confirmed that the multi-point stretch forming process has the capability and feasibility of being used to manufacture the double curved surfaces of sheet metal.Keywords: multi-point stretch forming, double curved surface, numerical simulation, manufacturing
Procedia PDF Downloads 47430388 Micro-Cantilever Tests on Hydride Blister and Zirconium Matrix of Zircaloy-4 Cladding Tube
Authors: Ho-A Kim, Jae-Soo Noh
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During reactor operation, hydride blister can occur in spent nuclear fuel (SNF) claddings, and it could worsen the integrity of the claddings locally. Hydride blister can be critical when a pinch-type load is applied in the process of SNF handling and transportation. Micro-cantilever tests were performed to evaluate the risk of local hydride blister by comparing the fracture toughness of local hydride blister and pre-hydrided Zr alloy matrix of SNF cladding on a microscale. Hydride blister was generated by a gaseous charging procedure to simulate an SNF cladding. Micro-cantilevers and pre-cracks were ion-milled with the Ga+ ion beam of FEI Helios 600 at 30kV acceleration voltage. Micro-cantilever tests were conducted using PI 85 pico-indenter (HYSTRON) with for sided conductive diamond flat tip (1 μm x 1 μm) at a speed of 5 nm/sec. The results show that the hydride blister specimen could be fractured in the elastic deformation region, and the fracture toughness of the hydride blister specimen could drop up to 60% of that of the pre-hydrided Zr alloy matrix. Therefore, local hydride blister can degrade the integrity of SNF cladding, and the effect of hydride blister should be taken into account when evaluating failure criteria of claddings during handling, storage, and transportation of SNF.Keywords: fracture toughness, hydride blister, micro-cantilever test, spent nuclear fuel cladding.
Procedia PDF Downloads 13230387 Physicochemical Characterization of MFI–Ceramic Hollow Fibres Membranes for CO2 Separation with Alkali Metal Cation
Authors: A. Alshebani, Y. Swesi, S. Mrayed, F. Altaher
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This paper present some preliminary work on the preparation and physicochemical caracterization of nanocomposite MFI-alumina structures based on alumina hollow fibres. The fibers are manufactured by a wet spinning process. α-alumina particles were dispersed in a solution of polysulfone in NMP. The resulting slurry is pressed through the annular gap of a spinneret into a precipitation bath. The resulting green fibres are sintered. The mechanical strength of the alumina hollow fibres is determined by a three-point-bending test while the pore size is characterized by bubble-point testing. The bending strength is in the range of 110 MPa while the average pore size is 450 nm for an internal diameter of 1 mm and external diameter of 1.7 mm. To characterize the MFI membranes various techniques were used for physicochemical characterization of MFI–ceramic hollow fibres membranes: The nitrogen adsorption, X-ray diffractometry, scanning electron microscopy combined with X emission microanalysis. Scanning Electron Microscopy (SEM) and Energy Dispersive Microanalysis by the X-ray were used to observe the morphology of the hollow fibre membranes (thickness, infiltration into the carrier, defects, homogeneity). No surface film, has been obtained, as observed by SEM and EDX analysis and confirmed by high temperature variation of N2 and CO2 gas permeances before cation exchange. Local analysis and characterise (SEM and EDX) and overall (by ICP elemental analysis) were conducted on two samples exchanged to determine the quantity and distribution of the cation of cesium on the cross section fibre of the zeolite between the cavities.Keywords: physicochemical characterization of MFI, ceramic hollow fibre, CO2, ion-exchange
Procedia PDF Downloads 34430386 Explicit Iterative Scheme for Approximating a Common Solution of Generalized Mixed Equilibrium Problem and Fixed Point Problem for a Nonexpansive Semigroup in Hilbert Space
Authors: Mohammad Farid
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In this paper, we introduce and study an explicit iterative method based on hybrid extragradient method to approximate a common solution of generalized mixed equilibrium problem and fixed point problem for a nonexpansive semigroup in Hilbert space. Further, we prove that the sequence generated by the proposed iterative scheme converge strongly to the common solution of generalized mixed equilibrium problem and fixed point problem for a nonexpansive semigroup. This common solution is the unique solution of a variational inequality problem and is the optimality condition for a minimization problem. The results presented in this paper are the supplement, extension and generalization of the previously known results in this area.Keywords: generalized mixed equilibrium problem, fixed-point problem, nonexpansive semigroup, variational inequality problem, iterative algorithms, hybrid extragradient method
Procedia PDF Downloads 46830385 Determiner Phrase in Persian
Authors: Reza Morad Sahraei, Roghayeh Kazeminahad
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Surveying the structure of NP in Persian, this article tries to show that most of NP constituents are either independent of each other or they are dependent to Determiner Phrase (=DP). The writer follows a uniform minimal analysis to illustrate the structural position of relevant constituents of DP, including Possessive Phrase, Ezafat Phrase and Quantifier Phrase, under the tree diagram. The most important point of this article is the claim that NP is mostly one of the dependents of DP. Hence, the final section of the article deals with and analyzes the structure of DP in Persian. The DP analysis undertaken in this article has some advantages. It can explain the internal relevance of all DP constituents and provides them all a uniform analysis. Also, the semantic importance of Persian genitive marker and its role in parsing is borne out.Keywords: determiner phrase (DP), ezafat phrase (Ezaf P), noun phrase(NP), possessive phrase (PossP), quantifier phrase (QP)
Procedia PDF Downloads 57530384 Vantage Point–Visual Culture, Popular Media, and Contemporary Educational Practice
Authors: Elvin Karaaslan Klose
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In the field of Visual Culture, Art Education students are given the opportunity to discuss topics of interest that are closer to their own social life and media consumption habits. In contrast to the established corpus of literature and sources about Art History, educators are challenged to find topics and examples from Popular Culture and Contemporary Art that provide familiarity, depth and inspiration for students’ future practice, both as educators as well as artists. In order to establish a welcoming and fruitful discussion environment at the beginning of an introductory Visual Culture Education course with fourth year Art Education students, the class watched and subsequently discussed the movie “Vantage Point”. Using the descriptive method and content analysis; video recordings, discussion transcripts and learning diaries were summarized to highlight students’ critical points of view towards commonly experienced but rarely reflected on topics of Popular and Visual Culture. As an introduction into more theory-based forms of discussion, watching and intensely discussing a movie has proven useful by proving a combination of a familiar media type with an unfamiliar educational context. Resulting areas of interest have served as a starting point for later research, discussion and artistic production in the scope of an introductory Visual Culture Education course.Keywords: visual culture, critical pedagogy, media literacy, art education
Procedia PDF Downloads 66630383 Investigation on Performance of Change Point Algorithm in Time Series Dynamical Regimes and Effect of Data Characteristics
Authors: Farhad Asadi, Mohammad Javad Mollakazemi
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In this paper, Bayesian online inference in models of data series are constructed by change-points algorithm, which separated the observed time series into independent series and study the change and variation of the regime of the data with related statistical characteristics. variation of statistical characteristics of time series data often represent separated phenomena in the some dynamical system, like a change in state of brain dynamical reflected in EEG signal data measurement or a change in important regime of data in many dynamical system. In this paper, prediction algorithm for studying change point location in some time series data is simulated. It is verified that pattern of proposed distribution of data has important factor on simpler and smother fluctuation of hazard rate parameter and also for better identification of change point locations. Finally, the conditions of how the time series distribution effect on factors in this approach are explained and validated with different time series databases for some dynamical system.Keywords: time series, fluctuation in statistical characteristics, optimal learning, change-point algorithm
Procedia PDF Downloads 41830382 Theoretical Approach to Kinetics of Transient Plasticity of Metals under Irradiation
Authors: Pavlo Selyshchev, Tetiana Didenko
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Within the framework of the obstacle radiation hardening and the dislocation climb-glide model a theoretical approach is developed to describe peculiarities of transient plasticity of metal under irradiation. It is considered nonlinear dynamics of accumulation of point defects (vacancies and interstitial atoms). We consider metal under such stress and conditions of irradiation at which creep is determined by dislocation motion: dislocations climb obstacles and glide between obstacles. It is shown that the rivalry between vacancy and interstitial fluxes to dislocation leads to fractures of plasticity time dependence. Simulation and analysis of this phenomenon are performed. Qualitatively different regimes of transient plasticity under irradiation are found. The fracture time is obtained. The theoretical results are compared with the experimental ones.Keywords: climb and glide of dislocations, fractures of transient plasticity, irradiation, non-linear feed-back, point defects
Procedia PDF Downloads 19530381 Finding the Optimal Meeting Point Based on Travel Plans in Road Networks
Authors: Mohammad H. Ahmadi, Vahid Haghighatdoost
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Given a set of source locations for a group of friends, and a set of trip plans for each group member as a sequence of Categories-of-Interests (COIs) (e.g., restaurant), and finally a specific COI as a common destination that all group members will gather together, in Meeting Point Based on Trip Plans (MPTPs) queries our goal is to find a Point-of-Interest (POI) from different COIs, such that the aggregate travel distance for the group is minimized. In this work, we considered two cases for aggregate function as Sum and Max. For solving this query, we propose an efficient pruning technique for shrinking the search space. Our approach contains three steps. In the first step, it prunes the search space around the source locations. In the second step, it prunes the search space around the centroid of source locations. Finally, we compute the intersection of all pruned areas as the final refined search space. We prove that the POIs beyond the refined area cannot be part of optimal answer set. The paper also covers an extensive performance study of the proposed technique.Keywords: meeting point, trip plans, road networks, spatial databases
Procedia PDF Downloads 17930380 Simulation and Analysis of Inverted Pendulum Controllers
Authors: Sheren H. Salah
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The inverted pendulum is a highly nonlinear and open-loop unstable system. An inverted pendulum (IP) is a pendulum which has its mass above its pivot point. It is often implemented with the pivot point mounted on a cart that can move horizontally and may be called a cart and pole. The characteristics of the inverted pendulum make identification and control more challenging. This paper presents the simulation study of several control strategies for an inverted pendulum system. The goal is to determine which control strategy delivers better performance with respect to pendulum’s angle. The inverted pendulum represents a challenging control problem, which continually moves toward an uncontrolled state. For controlling the inverted pendulum. The simulation study that sliding mode control (SMC) control produced better response compared to Genetic Algorithm Control (GAs) and proportional-integral-derivative(PID) control.Keywords: Inverted Pendulum (IP) Proportional-Integral-Derivative (PID), Genetic Algorithm Control (GAs), Sliding Mode Control (SMC)
Procedia PDF Downloads 55130379 Numerical and Experimental Investigation of Mixed-Mode Fracture of Cement Paste and Interface Under Three-Point Bending Test
Authors: S. Al Dandachli, F. Perales, Y. Monerie, F. Jamin, M. S. El Youssoufi, C. Pelissou
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The goal of this research is to study the fracture process and mechanical behavior of concrete under I–II mixed-mode stress, which is essential for ensuring the safety of concrete structures. For this purpose, two-dimensional simulations of three-point bending tests under variable load and geometry on notched cement paste samples of composite samples (cement paste/siliceous aggregate) are modeled by employing Cohesive Zone Models (CZMs). As a result of experimental validation of these tests, the CZM model demonstrates its capacity to predict fracture propagation at the local scale.Keywords: cement paste, interface, cohesive zone model, fracture, three-point flexural test bending
Procedia PDF Downloads 13930378 A Hybrid Heuristic for the Team Orienteering Problem
Authors: Adel Bouchakhchoukha, Hakim Akeb
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In this work, we propose a hybrid heuristic in order to solve the Team Orienteering Problem (TOP). Given a set of points (or customers), each with associated score (profit or benefit), and a team that has a fixed number of members, the problem to solve is to visit a subset of points in order to maximize the total collected score. Each member performs a tour starting at the start point, visiting distinct customers and the tour terminates at the arrival point. In addition, each point is visited at most once, and the total time in each tour cannot be greater than a given value. The proposed heuristic combines beam search and a local optimization strategy. The algorithm was tested on several sets of instances and encouraging results were obtained.Keywords: team orienteering problem, vehicle routing, beam search, local search
Procedia PDF Downloads 41430377 The Grinding Influence on the Strength of Fan-Out Wafer-Level Packages
Authors: Z. W. Zhong, C. Xu, W. K. Choi
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To build a thin fan-out wafer-level package, the package had to be ground to a thin level. In this work, the influence of the grinding processes on the strength of the fan-out wafer-level packages was investigated. After different grinding processes, all specimens were placed on a three-point-bending fixture installed on a universal tester for three-point-bending testing, and the strength of the fan-out wafer-level packages was measured. The experiments revealed that the average flexure strength increased with the decreasing surface roughness height of the fan-out wafer-level package tested. The grinding processes had a significant influence on the strength of the fan-out wafer-level packages investigated.Keywords: FOWLP strength, surface roughness, three-point bending, grinding
Procedia PDF Downloads 27430376 Geothermal Energy Evaluation of Lower Benue Trough Using Spectral Analysis of Aeromagnetic Data
Authors: Stella C. Okenu, Stephen O. Adikwu, Martins E. Okoro
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The geothermal energy resource potential of the Lower Benue Trough (LBT) in Nigeria was evaluated in this study using spectral analysis of high-resolution aeromagnetic (HRAM) data. The reduced to the equator aeromagnetic data was divided into sixteen (16) overlapping blocks, and each of the blocks was analyzed to obtain the radial averaged power spectrum which enabled the computation of the top and centroid depths to magnetic sources. The values were then used to assess the Curie Point Depth (CPD), geothermal gradients, and heat flow variations in the study area. Results showed that CPD varies from 7.03 to 18.23 km, with an average of 12.26 km; geothermal gradient values vary between 31.82 and 82.50°C/km, with an average of 51.21°C/km, while heat flow variations range from 79.54 to 206.26 mW/m², with an average of 128.02 mW/m². Shallow CPD zones that run from the eastern through the western and southwestern parts of the study area correspond to zones of high geothermal gradient values and high subsurface heat flow distributions. These areas signify zones associated with anomalous subsurface thermal conditions and are therefore recommended for detailed geothermal energy exploration studies.Keywords: geothermal energy, curie-point depth, geothermal gradient, heat flow, aeromagnetic data, LBT
Procedia PDF Downloads 6930375 Evaluation of Photovoltaic System with Different Research Methods of Maximum Power Point Tracking
Authors: Mehdi Ameur, Ahmed Essadki, Tamou Nasser
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The purpose of this paper is the evaluation of photovoltaic system with MPPT techniques. This system is developed by combining the models of established solar module and DC-DC converter with the algorithms of perturbing and observing (P&O), incremental conductance (INC) and fuzzy logic controller (FLC). The system is simulated under different climate conditions and MPPT algorithms to determine the influence of these conditions on characteristic power-voltage of PV system. According to the comparisons of the simulation results, the photovoltaic system can extract the maximum power with precision and rapidity using the MPPT algorithms discussed in this paper.Keywords: fuzzy logic controller, FLC, hill climbing, HC, incremental conductance (INC), perturb and observe (P&O), maximum power point, MPP, maximum power point tracking, MPPT
Procedia PDF Downloads 50530374 Curvature Based-Methods for Automatic Coarse and Fine Registration in Dimensional Metrology
Authors: Rindra Rantoson, Hichem Nouira, Nabil Anwer, Charyar Mehdi-Souzani
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Multiple measurements by means of various data acquisition systems are generally required to measure the shape of freeform workpieces for accuracy, reliability and holisticity. The obtained data are aligned and fused into a common coordinate system within a registration technique involving coarse and fine registrations. Standardized iterative methods have been established for fine registration such as Iterative Closest Points (ICP) and its variants. For coarse registration, no conventional method has been adopted yet despite a significant number of techniques which have been developed in the literature to supply an automatic rough matching between data sets. Two main issues are addressed in this paper: the coarse registration and the fine registration. For coarse registration, two novel automated methods based on the exploitation of discrete curvatures are presented: an enhanced Hough Transformation (HT) and an improved Ransac Transformation. The use of curvature features in both methods aims to reduce computational cost. For fine registration, a new variant of ICP method is proposed in order to reduce registration error using curvature parameters. A specific distance considering the curvature similarity has been combined with Euclidean distance to define the distance criterion used for correspondences searching. Additionally, the objective function has been improved by combining the point-to-point (P-P) minimization and the point-to-plane (P-Pl) minimization with automatic weights. These ones are determined from the preliminary calculated curvature features at each point of the workpiece surface. The algorithms are applied on simulated and real data performed by a computer tomography (CT) system. The obtained results reveal the benefit of the proposed novel curvature-based registration methods.Keywords: discrete curvature, RANSAC transformation, hough transformation, coarse registration, ICP variant, point-to-point and point-to-plane minimization combination, computer tomography
Procedia PDF Downloads 41830373 The Use of Random Set Method in Reliability Analysis of Deep Excavations
Authors: Arefeh Arabaninezhad, Ali Fakher
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Since the deterministic analysis methods fail to take system uncertainties into account, probabilistic and non-probabilistic methods are suggested. Geotechnical analyses are used to determine the stress and deformation caused by construction; accordingly, many input variables which depend on ground behavior are required for geotechnical analyses. The Random Set approach is an applicable reliability analysis method when comprehensive sources of information are not available. Using Random Set method, with relatively small number of simulations compared to fully probabilistic methods, smooth extremes on system responses are obtained. Therefore random set approach has been proposed for reliability analysis in geotechnical problems. In the present study, the application of random set method in reliability analysis of deep excavations is investigated through three deep excavation projects which were monitored during the excavating process. A finite element code is utilized for numerical modeling. Two expected ranges, from different sources of information, are established for each input variable, and a specific probability assignment is defined for each range. To determine the most influential input variables and subsequently reducing the number of required finite element calculations, sensitivity analysis is carried out. Input data for finite element model are obtained by combining the upper and lower bounds of the input variables. The relevant probability share of each finite element calculation is determined considering the probability assigned to input variables present in these combinations. Horizontal displacement of the top point of excavation is considered as the main response of the system. The result of reliability analysis for each intended deep excavation is presented by constructing the Belief and Plausibility distribution function (i.e. lower and upper bounds) of system response obtained from deterministic finite element calculations. To evaluate the quality of input variables as well as applied reliability analysis method, the range of displacements extracted from models has been compared to the in situ measurements and good agreement is observed. The comparison also showed that Random Set Finite Element Method applies to estimate the horizontal displacement of the top point of deep excavation. Finally, the probability of failure or unsatisfactory performance of the system is evaluated by comparing the threshold displacement with reliability analysis results.Keywords: deep excavation, random set finite element method, reliability analysis, uncertainty
Procedia PDF Downloads 26430372 Temporally Coherent 3D Animation Reconstruction from RGB-D Video Data
Authors: Salam Khalifa, Naveed Ahmed
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We present a new method to reconstruct a temporally coherent 3D animation from single or multi-view RGB-D video data using unbiased feature point sampling. Given RGB-D video data, in form of a 3D point cloud sequence, our method first extracts feature points using both color and depth information. In the subsequent steps, these feature points are used to match two 3D point clouds in consecutive frames independent of their resolution. Our new motion vectors based dynamic alignment method then fully reconstruct a spatio-temporally coherent 3D animation. We perform extensive quantitative validation using novel error functions to analyze the results. We show that despite the limiting factors of temporal and spatial noise associated to RGB-D data, it is possible to extract temporal coherence to faithfully reconstruct a temporally coherent 3D animation from RGB-D video data.Keywords: 3D video, 3D animation, RGB-D video, temporally coherent 3D animation
Procedia PDF Downloads 36730371 Competitors’ Influence Analysis of a Retailer by Using Customer Value and Huff’s Gravity Model
Authors: Yepeng Cheng, Yasuhiko Morimoto
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Customer relationship analysis is vital for retail stores, especially for supermarkets. The point of sale (POS) systems make it possible to record the daily purchasing behaviors of customers as an identification point of sale (ID-POS) database, which can be used to analyze customer behaviors of a supermarket. The customer value is an indicator based on ID-POS database for detecting the customer loyalty of a store. In general, there are many supermarkets in a city, and other nearby competitor supermarkets significantly affect the customer value of customers of a supermarket. However, it is impossible to get detailed ID-POS databases of competitor supermarkets. This study firstly focused on the customer value and distance between a customer's home and supermarkets in a city, and then constructed the models based on logistic regression analysis to analyze correlations between distance and purchasing behaviors only from a POS database of a supermarket chain. During the modeling process, there are three primary problems existed, including the incomparable problem of customer values, the multicollinearity problem among customer value and distance data, and the number of valid partial regression coefficients. The improved customer value, Huff’s gravity model, and inverse attractiveness frequency are considered to solve these problems. This paper presents three types of models based on these three methods for loyal customer classification and competitors’ influence analysis. In numerical experiments, all types of models are useful for loyal customer classification. The type of model, including all three methods, is the most superior one for evaluating the influence of the other nearby supermarkets on customers' purchasing of a supermarket chain from the viewpoint of valid partial regression coefficients and accuracy.Keywords: customer value, Huff's Gravity Model, POS, Retailer
Procedia PDF Downloads 11730370 Studies on the Physicochemical Properties of Biolubricants Obtained from Vegetable Oils and Their Oxidative Stability
Authors: Expedito J. S. Parente Jr., Italo C. Rios, Joao Paulo C. Marques, Rosana M. A. Saboya, F. Murilo T. Luna, Célio L. Cavalcante Jr.
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Increasing constraints of environmental regulation around the world have led to higher demand for biodegradable products. Vegetable oils present some properties that may favor their use as biolubricants; however, there are others, such as resistance to oxidation and pour point, which affect possible commercial applications. In this study, the physicochemical properties of biolubricants synthesized from different vegetable oils were evaluated and compared with petroleum-based lubricant and pure vegetable oil. Chemical modifications applied to the original vegetable oil improved their oxidative stability and pour point significantly. The addition of commercial antioxidants to the bio-based lubricants was evaluated, yielding values of oxidative stability close to those of mineral basestock oil.Keywords: biolubricant, vegetable oil, oxidative stability, pour point, antioxidants
Procedia PDF Downloads 30730369 Fault Prognostic and Prediction Based on the Importance Degree of Test Point
Authors: Junfeng Yan, Wenkui Hou
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Prognostics and Health Management (PHM) is a technology to monitor the equipment status and predict impending faults. It is used to predict the potential fault and provide fault information and track trends of system degradation by capturing characteristics signals. So how to detect characteristics signals is very important. The select of test point plays a very important role in detecting characteristics signal. Traditionally, we use dependency model to select the test point containing the most detecting information. But, facing the large complicated system, the dependency model is not built so easily sometimes and the greater trouble is how to calculate the matrix. Rely on this premise, the paper provide a highly effective method to select test point without dependency model. Because signal flow model is a diagnosis model based on failure mode, which focuses on system’s failure mode and the dependency relationship between the test points and faults. In the signal flow model, a fault information can flow from the beginning to the end. According to the signal flow model, we can find out location and structure information of every test point and module. We break the signal flow model up into serial and parallel parts to obtain the final relationship function between the system’s testability or prediction metrics and test points. Further, through the partial derivatives operation, we can obtain every test point’s importance degree in determining the testability metrics, such as undetected rate, false alarm rate, untrusted rate. This contributes to installing the test point according to the real requirement and also provides a solid foundation for the Prognostics and Health Management. According to the real effect of the practical engineering application, the method is very efficient.Keywords: false alarm rate, importance degree, signal flow model, undetected rate, untrusted rate
Procedia PDF Downloads 37330368 Performance of the Cmip5 Models in Simulation of the Present and Future Precipitation over the Lake Victoria Basin
Authors: M. A. Wanzala, L. A. Ogallo, F. J. Opijah, J. N. Mutemi
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The usefulness and limitations in climate information are due to uncertainty inherent in the climate system. For any given region to have sustainable development it is important to apply climate information into its socio-economic strategic plans. The overall objective of the study was to assess the performance of the Coupled Model Inter-comparison Project (CMIP5) over the Lake Victoria Basin. The datasets used included the observed point station data, gridded rainfall data from Climate Research Unit (CRU) and hindcast data from eight CMIP5. The methodology included trend analysis, spatial analysis, correlation analysis, Principal Component Analysis (PCA) regression analysis, and categorical statistical skill score. Analysis of the trends in the observed rainfall records indicated an increase in rainfall variability both in space and time for all the seasons. The spatial patterns of the individual models output from the models of MPI, MIROC, EC-EARTH and CNRM were closest to the observed rainfall patterns.Keywords: categorical statistics, coupled model inter-comparison project, principal component analysis, statistical downscaling
Procedia PDF Downloads 36330367 Holographic Visualisation of 3D Point Clouds in Real-time Measurements: A Proof of Concept Study
Authors: Henrique Fernandes, Sofia Catalucci, Richard Leach, Kapil Sugand
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Background: Holograms are 3D images formed by the interference of light beams from a laser or other coherent light source. Pepper’s ghost is a form of hologram conceptualised in the 18th century. This Holographic visualisation with metrology measuring techniques by displaying measurements taken in real-time in holographic form can assist in research and education. New structural designs such as the Plexiglass Stand and the Hologram Box can optimise the holographic experience. Method: The equipment used included: (i) Zeiss’s ATOS Core 300 optical coordinate measuring instrument that scanned real-world objects; (ii) Cloud Compare, open-source software used for point cloud processing; and (iii) Hologram Box, designed and manufactured during this research to provide the blackout environment needed to display 3D point clouds in real-time measurements in holographic format, in addition to a portability aspect to holograms. The equipment was tailored to realise the goal of displaying measurements in an innovative technique and to improve on conventional methods. Three test scans were completed before doing a holographic conversion. Results: The outcome was a precise recreation of the original object in the holographic form presented with dense point clouds and surface density features in a colour map. Conclusion: This work establishes a way to visualise data in a point cloud system. To our understanding, this is a work that has never been attempted. This achievement provides an advancement in holographic visualisation. The Hologram Box could be used as a feedback tool for measurement quality control and verification in future smart factories.Keywords: holography, 3D scans, hologram box, metrology, point cloud
Procedia PDF Downloads 8230366 Modification of Newton Method in Two Point Block Backward Differentiation Formulas
Authors: Khairil I. Othman, Nur N. Kamal, Zarina B. Ibrahim
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In this paper, we present modified Newton method as a new strategy for improving the efficiency of Two Point Block Backward Differentiation Formulas (BBDF) when solving stiff systems of ordinary differential equations (ODEs). These methods are constructed to produce two approximate solutions simultaneously at each iteration The detailed implementation of the predictor corrector BBDF with PE(CE)2 with modified Newton are discussed. The proposed modification of BBDF is validated through numerical results on some standard problems found in the literature and comparisons are made with the existing Block Backward Differentiation Formula. Numerical results show the advantage of using the new strategy for solving stiff ODEs in improving the accuracy of the solution.Keywords: newton method, two point, block, accuracy
Procedia PDF Downloads 35030365 Correlation between Cephalometric Measurements and Visual Perception of Facial Profile in Skeletal Type II Patients
Authors: Choki, Supatchai Boonpratham, Suwannee Luppanapornlarp
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The objective of this study was to find a correlation between cephalometric measurements and visual perception of facial profile in skeletal type II patients. In this study, 250 lateral cephalograms of female patients from age, 20 to 22 years were analyzed. The profile outlines of all the samples were hand traced and transformed into silhouettes by the principal investigator. Profile ratings were done by 9 orthodontists on Visual Analogue Scale from score one to ten (increasing level of convexity). 37 hard issue and soft tissue cephalometric measurements were analyzed by the principal investigator. All the measurements were repeated after 2 weeks interval for error assessment. At last, the rankings of visual perceptions were correlated with cephalometric measurements using Spearman correlation coefficient (P < 0.05). The results show that the increase in facial convexity was correlated with higher values of ANB (A point, nasion and B point), AF-BF (distance from A point to B point in mm), L1-NB (distance from lower incisor to NB line in mm), anterior maxillary alveolar height, posterior maxillary alveolar height, overjet, H angle hard tissue, H angle soft tissue and lower lip to E plane (absolute correlation values from 0.277 to 0.711). In contrast, the increase in facial convexity was correlated with lower values of Pg. to N perpendicular and Pg. to NB (mm) (absolute correlation value -0.302 and -0.294 respectively). From the soft tissue measurements, H angles had a higher correlation with visual perception than facial contour angle, nasolabial angle, and lower lip to E plane. In conclusion, the findings of this study indicated that the correlation of cephalometric measurements with visual perception was less than expected. Only 29% of cephalometric measurements had a significant correlation with visual perception. Therefore, diagnosis based solely on cephalometric analysis can result in failure to meet the patient’s esthetic expectation.Keywords: cephalometric measurements, facial profile, skeletal type II, visual perception
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