Search results for: Peng Cheng
581 Performances Analysis of the Pressure and Production of an Oil Zone by Simulation of the Flow of a Fluid through the Porous Media
Authors: Makhlouf Mourad, Medkour Mihoub, Bouchher Omar, Messabih Sidi Mohamed, Benrachedi Khaled
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This work is the modeling and simulation of fluid flow (liquid) through porous media. This type of flow occurs in many situations of interest in applied sciences and engineering, fluid (oil) consists of several individual substances in pure, single-phase flow is incompressible and isothermal. The porous medium is isotropic, homogeneous optionally, with the rectangular format and the flow is two-dimensional. Modeling of hydrodynamic phenomena incorporates Darcy's law and the equation of mass conservation. Correlations are used to model the density and viscosity of the fluid. A finite volume code is used in the discretization of differential equations. The nonlinearity is treated by Newton's method with relaxation coefficient. The results of the simulation of the pressure and the mobility of liquid flowing through porous media are presented, analyzed, and illustrated.Keywords: Darcy equation, middle porous, continuity equation, Peng Robinson equation, mobility
Procedia PDF Downloads 219580 On the Framework of Contemporary Intelligent Mathematics Underpinning Intelligent Science, Autonomous AI, and Cognitive Computers
Authors: Yingxu Wang, Jianhua Lu, Jun Peng, Jiawei Zhang
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The fundamental demand in contemporary intelligent science towards Autonomous AI (AI*) is the creation of unprecedented formal means of Intelligent Mathematics (IM). It is discovered that natural intelligence is inductively created rather than exhaustively trained. Therefore, IM is a family of algebraic and denotational mathematics encompassing Inference Algebra, Real-Time Process Algebra, Concept Algebra, Semantic Algebra, Visual Frame Algebra, etc., developed in our labs. IM plays indispensable roles in training-free AI* theories and systems beyond traditional empirical data-driven technologies. A set of applications of IM-driven AI* systems will be demonstrated in contemporary intelligence science, AI*, and cognitive computers.Keywords: intelligence mathematics, foundations of intelligent science, autonomous AI, cognitive computers, inference algebra, real-time process algebra, concept algebra, semantic algebra, applications
Procedia PDF Downloads 61579 Influence of Bacterial Motility on Biofilm Formation
Authors: Li Cheng, Zhang Yilei, Cohen Yehuda
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Two motility mechanisms were introduced into iDynoMiCs software, which adopts an individual-based modeling method. Based on the new capabilities, along with the pressure motility developed before, influence of bacterial motility on biofilm formation was studied. Simulation results were evaluated both qualitatively through 3D structure inspections and quantitatively by parameter characterizations. It was showed that twitching motility increased the biofilm surface irregularity probably due to movement of cells towards higher nutrient concentration location whereas free motility, on the other hand, could make biofilms flatter and smoother relatively. Pressure motility showed no significant influence in this study.Keywords: iDynoMics, biofilm structure, bacterial motility, motility mechanisms
Procedia PDF Downloads 390578 Share Pledging and Financial Constraints in China
Authors: Zijian Cheng, Frank Liu, Yupu Sun
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The relationship between the intensity of share pledging activities and the level of financial constraint in publicly listed firms in China is examined in this paper. Empirical results show that the high financial constraint level may motivate insiders to use share pledging as an alternative funding source and an expropriation mechanism. Share collateralization can cause a subsequently more constrained financing condition. Evidence is found that share pledging made by the controlling shareholder is likely to mitigate financial constraints in the following year. Research findings are robust to alternative measures and an instrumental variable for dealing with endogeneity problems.Keywords: share pledge, financial constraint, controlling shareholder, dividend policy
Procedia PDF Downloads 165577 Direct Palladium-Catalyzed Selective N-Allylation of 2,3-Disubstituted Indoles with Allylic Alcohols in Water
Authors: Bai-Jing Peng, Shyh-Chyun Yang
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Organic reactions in water have recently attracted much attention, not only because unique reactivity is often observed in water but also because water is a safe and economical substitute for conventional organic solvents. Thus, development of environmental safe, atom-economical reactions in water is one of the most important goals of synthetic chemistry. The recent paper has documented renewed interest in the use of allylic substrates in the synthesis of new C−C, C−N, and C−O bonds. We have reported our attempts and some successful applications of a process involving the C-O bond cleavage catalyzed by palladium or platinum complexes in water. Because of the importance of heterocycle indole derivatives, much effort has been directed toward the development of methods for functionalization of the indole nucleus at N1 site. In our research, the palladium-catalyzed 2,3-disubstitued indoles with allylic alcohols was investigated under different conditions. Herein, we will establish a simple, convenient, and efficient method, which affords high yields of allylated indoles.Keywords: palladium-catalyzed, allylic alcohols, indoles, water, allylation
Procedia PDF Downloads 239576 Connections among Personality, Teacher-Student Relationship, Belief in a Just World for Others and Teacher Bullying
Authors: Hui-Yu Peng, Hsiu-I Hsueh, Li-Ming Chen
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Most studies focused on bullying behaviors among students, however few research concerns about teachers’ bullying behaviors against students. In order to have more understandings and reduce teacher bullying, it is important to examine what factors may affect teachers’ bullying behaviors. This study aimed to explore the connections between different psychological variables and teacher bullying. Four variables, neuroticism, extraversion, teacher-student relationship, and belief in a just world for others (BJW-others), were selected in this study. Four hundred and five elementary and secondary school teachers in Taiwan endorsed the self-reported surveys. Multiple regression method was used to analyze data. Results revealed that teachers’ BJW-others and extraversion did not have significant correlations with teacher bullying scores. However, closed teacher-student relationship and neuroticism can negatively and positively predict teachers’ bullying behaviors against students, respectively. Implications for preventing teacher bullying were discussed at the end of this study.Keywords: belief in a just world for others, big five personality traits, teacher bullying, teacher-student relationship
Procedia PDF Downloads 213575 Statistical Analysis of Cables in Long-Span Cable-Stayed Bridges
Authors: Ceshi Sun, Yueyu Zhao, Yaobing Zhao, Zhiqiang Wang, Jian Peng, Pengxin Guo
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With the rapid development of transportation, there are more than 100 cable-stayed bridges with main span larger than 300 m in China. In order to ascertain the statistical relationships among the design parameters of stay cables and their distribution characteristics, 1500 cables were selected from 25 practical long-span cable-stayed bridges. A new relationship between the first order frequency and the length of cable was found by conducting the curve fitting. Then, based on this relationship other interesting relationships were deduced. Several probability density functions (PDFs) were used to investigate the distributions of the parameters of first order frequency, stress level and the Irvine parameter. It was found that these parameters obey the Lognormal distribution, the Weibull distribution and the generalized Pareto distribution, respectively. Scatter diagrams of the three parameters were plotted and their 95% confidence intervals were also investigated.Keywords: cable, cable-stayed bridge, long-span, statistical analysis
Procedia PDF Downloads 635574 Condensation of Vapor in the Presence of Non-Condensable Gas on a Vertical Tube
Authors: Shengjun Zhang, Xu Cheng, Feng Shen
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The passive containment cooling system (PCCS) is widely used in the advanced nuclear reactor in case of the loss of coolant accident (LOCA) and the main steam line break accident (MSLB). The internal heat exchanger is one of the most important equipment in the PCCS and its heat transfer characteristic determines the performance of the system. In this investigation, a theoretical model is presented for predicting the heat and mass transfer which accompanies condensation. The conduction through the liquid condensate is considered and the interface temperature is defined by iteration. The parameter in the correlation to describe the suction effect should be further determined through experimental data.Keywords: non-condensable gas, condensation, heat transfer coefficient, heat and mass transfer analogy
Procedia PDF Downloads 350573 A Learning-Based EM Mixture Regression Algorithm
Authors: Yi-Cheng Tian, Miin-Shen Yang
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The mixture likelihood approach to clustering is a popular clustering method where the expectation and maximization (EM) algorithm is the most used mixture likelihood method. In the literature, the EM algorithm had been used for mixture regression models. However, these EM mixture regression algorithms are sensitive to initial values with a priori number of clusters. In this paper, to resolve these drawbacks, we construct a learning-based schema for the EM mixture regression algorithm such that it is free of initializations and can automatically obtain an approximately optimal number of clusters. Some numerical examples and comparisons demonstrate the superiority and usefulness of the proposed learning-based EM mixture regression algorithm.Keywords: clustering, EM algorithm, Gaussian mixture model, mixture regression model
Procedia PDF Downloads 510572 The Investigation of LPG Injector Control Circuit on a Motorcycle
Authors: Bin-Wen Lan, Ying-Xin Chen, Hsueh-Cheng Yang
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Liquefied petroleum gas is a fuel that has high octane number and low carbon number. This paper uses MSC-51 controller to investigate the effect of liquefied petroleum gas (LPG) on exhaust emissions for different engine speeds in a single cylinder, four-stroke and spark ignition engine. The results indicate that CO, CO2 and NOX exhaust emissions are lower with the use of LPG compared to the use of unleaded gasoline by using the developed controller. The open-loop in the LPG injection system was controlled by MCS-51 single chip. The results show that if a SI engine is operated with LPG fuel rather than gasoline fuel under the same conditions, significant reduction in exhaust emissions can be achieved. In summary, LPG has positive effects on main exhaust emissions such as CO, CO2 and NOX.Keywords: LPG, control circuit, emission, MCS-51
Procedia PDF Downloads 501571 Visual Search Based Indoor Localization in Low Light via RGB-D Camera
Authors: Yali Zheng, Peipei Luo, Shinan Chen, Jiasheng Hao, Hong Cheng
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Most of traditional visual indoor navigation algorithms and methods only consider the localization in ordinary daytime, while we focus on the indoor re-localization in low light in the paper. As RGB images are degraded in low light, less discriminative infrared and depth image pairs are taken, as the input, by RGB-D cameras, the most similar candidates, as the output, are searched from databases which is built in the bag-of-word framework. Epipolar constraints can be used to relocalize the query infrared and depth image sequence. We evaluate our method in two datasets captured by Kinect2. The results demonstrate very promising re-localization results for indoor navigation system in low light environments.Keywords: indoor navigation, low light, RGB-D camera, vision based
Procedia PDF Downloads 464570 Residual Life Estimation of K-out-of-N Cold Standby System
Authors: Qian Zhao, Shi-Qi Liu, Bo Guo, Zhi-Jun Cheng, Xiao-Yue Wu
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Cold standby redundancy is considered to be an effective mechanism for improving system reliability and is widely used in industrial engineering. However, because of the complexity of the reliability structure, there is little literature studying on the residual life of cold standby system consisting of complex components. In this paper, a simulation method is presented to predict the residual life of k-out-of-n cold standby system. In practical cases, failure information of a system is either unknown, partly unknown or completely known. Our proposed method is designed to deal with the three scenarios, respectively. Differences between the procedures are analyzed. Finally, numerical examples are used to validate the proposed simulation method.Keywords: cold standby system, k-out-of-n, residual life, simulation sampling
Procedia PDF Downloads 401569 Triadic Relationship of Icon Design for Semi-Literate Communities
Authors: Peng-Hui Maffee Wan, Klarissa Ting Ting Chang, Rax Suen Chun Lung
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Icons, or pictorial and graphical objects, are commonly used in Human-Computer Interaction (HCI) fields as the mediator in order to communicate information to users. Yet there has been little studies focusing on a majority of the world’s population, semi-literate communities, in terms of the fundamental know-how for designing icons for such population. In this study, two sets of icons belonging in different icon taxonomy, abstract and concrete are designed for a mobile application for semi-literate agricultural communities. In this paper, we propose a triadic relationship of an icon, namely meaning, task and mental image, which inherits the triadic relationship of a sign. User testing with the application and a post-pilot questionnaire are conducted as the experimental approach in two rural villages in India. Icons belonging to concrete taxonomy perform better than abstract icons on the premise that the design of the icon fulfills the underlying rules of the proposed triadic relationship.Keywords: icon, GUI, mobile app, semi-literate
Procedia PDF Downloads 491568 Numerical Investigation of Oxy-Fuel Combustion in Gasoline Engine for Carbon Capture and Storage
Authors: Zhijun Peng, Xiang Li, Dayou Li, Raouf Mobasheri, Abdel Aitouche
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To implement carbon capture and storage (CCS) for eliminating carbon dioxide (CO₂) emissions, this paper describes a study on oxy-fuel combustion (OFC) with an ethanol-gasoline dual-fuel spark ignition (DFSI) engine under economical oxygen consumption at low and mid-high loads which was performed by 1D simulation. It is demonstrated that under OFC mode without other optimisation, brake mean effective pressure (BMEP) can meet the requirement at mid-high load, but it has a considerable decline at low load compared to conventional air combustion (CAC) mode. Moreover, there is a considerable deterioration in brake specific fuel consumption (BSFC) compared to that of CAC mode. A practical method is proposed to optimise the DFSI engine performance under OFC mode by changing intake charge components and utilising appropriate water injection (WI) strategies.Keywords: oxy-fuel combustion, dual-fuel spark ignition engine, ethanol, gasoline, computer simulation
Procedia PDF Downloads 92567 Research of Intrinsic Emittance of Thermal Cathode with Emission Nonuniformity
Authors: Yufei Peng, Zhen Qin, Jianbe Li, Jidong Long
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The thermal cathode is widely used in accelerators, FELs and kinds of vacuum electronics. However, emission nonuniformity exists due to surface profile, material distribution, temperature variation, crystal orientation, etc., which will cause intrinsic emittance growth, brightness decline, envelope size augment, device performance deterioration or even failure. To understand how emittance is manipulated by emission nonuniformity, an intrinsic emittance model consisting of contributions from macro and micro surface nonuniformity is developed analytically based on general thermal emission model at temperature limited regime according to a real 3mm cathode. The model shows relative emittance increased about 50% due to temperature variation, and less than 5% from several kinds of micro surface nonuniformity which is much smaller than other research. Otherwise, we also calculated emittance growth combining with Monte Carlo method and PIC simulation, experiments of emission uniformity and emittance measurement are going to be carried out separately.Keywords: thermal cathode, electron emission fluctuation, intrinsic emittance, surface nonuniformity, cathode lifetime
Procedia PDF Downloads 298566 Resistive Switching Characteristics of Resistive Random Access Memory Devices after Furnace Annealing Processes
Authors: Chi-Yan Chu, Kai-Chi Chuang, Huang-Chung Cheng
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In this study, the RRAM devices with the TiN/Ti/HfOx/TiN structure were fabricated, then the electrical characteristics of the devices without annealing and after 400 °C and 500 °C of the furnace annealing (FA) temperature processes were compared. The RRAM devices after the FA’s 400 °C showed the lower forming, set and reset voltages than the other devices without annealing. However, the RRAM devices after the FA’s 500 °C did not show any electrical characteristics because the TiN/Ti/HfOx/TiN device was oxidized, as shown in the XPS analysis. From these results, the RRAM devices after the FA’s 400 °C showed the best electrical characteristics.Keywords: RRAM, furnace annealing (FA), forming, set and reset voltages, XPS
Procedia PDF Downloads 372565 Fast Fourier Transform-Based Steganalysis of Covert Communications over Streaming Media
Authors: Jinghui Peng, Shanyu Tang, Jia Li
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Steganalysis seeks to detect the presence of secret data embedded in cover objects, and there is an imminent demand to detect hidden messages in streaming media. This paper shows how a steganalysis algorithm based on Fast Fourier Transform (FFT) can be used to detect the existence of secret data embedded in streaming media. The proposed algorithm uses machine parameter characteristics and a network sniffer to determine whether the Internet traffic contains streaming channels. The detected streaming data is then transferred from the time domain to the frequency domain through FFT. The distributions of power spectra in the frequency domain between original VoIP streams and stego VoIP streams are compared in turn using t-test, achieving the p-value of 7.5686E-176 which is below the threshold. The results indicate that the proposed FFT-based steganalysis algorithm is effective in detecting the secret data embedded in VoIP streaming media.Keywords: steganalysis, security, Fast Fourier Transform, streaming media
Procedia PDF Downloads 148564 Internal Capital Market Efficiency Study Based on Improved Cash Flow Sensitivity Coefficient - Take Tomorrow Group as an Example
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Because of the difficulty of financing from the external capital market, the reorganization and merger of private enterprises have formed a family group, seeking the help of the internal capital market to alleviate the capital demand. However, the inefficiency of the internal capital market can damage the effect it should have played, and even hinder the development of enterprises. This paper takes the "Tomorrow Group" as the research object to carry on the case analysis. After using the improved cash flow sensitivity coefficient to measure the efficiency of the internal capital market of Tomorrow Group, the inefficiency phenomenon is found. Then the analysis reveals that the reasons for its inefficiency include that the pyramidal equity structure is conducive to control, the separation of cash flow rights and control rights, the concentration of equity leads to poor balance, the abandonment of real industries and information asymmetry.Keywords: tomorrow group, internal capital market, related-party transactions, Baotou tomorrow technology Co., LTD
Procedia PDF Downloads 137563 A Survey of Crowdsourcing Technology
Authors: Qianjia Cheng, Hongquan Jiang
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Crowdsourcing solves the problems that computers can't handle by integrating computers and the Internet. Its extensive knowledge sources, high efficiency and high quality, make crowdsourcing attract wide attention in industry and academia in recent years. The development of online crowdsourcing platforms such as Clickworker and Amazon Mechanical Turk(Mturk) tend to mature gradually. This paper sorts out the concept of crowdsourcing, sorts out the workflow of competitive crowdsourcing, summarizes the related technologies of crowdsourcing based on the workflow, quality control, cost control and delay control, introduces the typical crowdsourcing platform. Finally, we highlight some open problems of the current crowdsourcing and present some future research direction in this area.Keywords: application, crowdsourcing, crowdsourcing platform, system architecture
Procedia PDF Downloads 70562 Copper Removal from Synthetic Wastewater by a Novel Fluidized-bed Homogeneous Crystallization (FBHC) Technology
Authors: Cheng-Yen Huang, Yu-Jen Shih, Ming-Chun Yen, Yao-Hui Huang
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This research developed a fluidized-bed homogeneous crystallization (FBHC) process to remove copper from synthetic wastewater in terms of recovery of highly pure malachite (Cu2(OH)2CO3) pellets. The experimental parameters of FBHC which included pH, molar ratio of copper to carbonate, copper loading, upper flowrate and bed height were tested in the absence of seed particles. Under optimized conditions, both the total copper removal (TR) and crystallization ratio (CR) reached 99%. The malachite crystals were characterized by XRD and SEM. FBHC was capable of treating concentrated copper (1600 ppm) wastewater and minimizing the sludge production.Keywords: copper, carbonate, fluidized-bed, crystallization, malachite
Procedia PDF Downloads 423561 Aspen Plus Simulation of Saponification of Ethyl Acetate in the Presence of Sodium Hydroxide in a Plug Flow Reactor
Authors: U. P. L. Wijayarathne, K. C. Wasalathilake
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This work presents the modelling and simulation of saponification of ethyl acetate in the presence of sodium hydroxide in a plug flow reactor using Aspen Plus simulation software. Plug flow reactors are widely used in the industry due to the non-mixing property. The use of plug flow reactors becomes significant when there is a need for continuous large scale reaction or fast reaction. Plug flow reactors have a high volumetric unit conversion as the occurrence for side reactions is minimum. In this research Aspen Plus V8.0 has been successfully used to simulate the plug flow reactor. In order to simulate the process as accurately as possible HYSYS Peng-Robinson EOS package was used as the property method. The results obtained from the simulation were verified by the experiment carried out in the EDIBON plug flow reactor module. The correlation coefficient (r2) was 0.98 and it proved that simulation results satisfactorily fit for the experimental model. The developed model can be used as a guide for understanding the reaction kinetics of a plug flow reactor.Keywords: aspen plus, modelling, plug flow reactor, simulation
Procedia PDF Downloads 603560 Characterization of the Dispersion Phenomenon in an Optical Biosensor
Authors: An-Shik Yang, Chin-Ting Kuo, Yung-Chun Yang, Wen-Hsin Hsieh, Chiang-Ho Cheng
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Optical biosensors have become a powerful detection and analysis tool for wide-ranging applications in biomedical research, pharmaceuticals and environmental monitoring. This study carried out the computational fluid dynamics (CFD)-based simulations to explore the dispersion phenomenon in the microchannel of a optical biosensor. The predicted time sequences of concentration contours were utilized to better understand the dispersion development occurred in different geometric shapes of microchannels. The simulation results showed the surface concentrations at the sensing probe (with the best performance of a grating coupler) in respect of time to appraise the dispersion effect and therefore identify the design configurations resulting in minimum dispersion.Keywords: CFD simulations, dispersion, microfluidic, optical waveguide sensors
Procedia PDF Downloads 545559 Identifying Dominant Anaerobic Microorganisms for Degradation of Benzene
Authors: Jian Peng, Wenhui Xiong, Zheng Lu
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An optimal recipe of amendment (nutrients and electron acceptors) was developed and dominant indigenous benzene-degrading microorganisms were characterized in this study. Lessons were learnt from the development of the optimal amendment recipe: (1) salinity and substantial initial concentration of benzene were detrimental for benzene biodegradation; (2) large dose of amendments can shorten the lag time for benzene biodegradation occurrence; (3) toluene was an essential co-substance for promoting benzene degradation activity. The stable isotope probing study identified incorporation 13C from 13C-benzene into microorganisms, which can be considered as a direct evidence of the occurrence of benzene biodegradation. The dominant mechanism for benzene removal was identified by quantitative polymerase chain reaction analysis to be nitrate reduction. Microbial analyses (denaturing gradient gel electrophoresis and 16S ribosomal RNA) demonstrated that members of genus Dokdonella spp., Pusillimonas spp., and Advenella spp. were predominant within the microbial community and involved in the anaerobic benzene bioremediation.Keywords: benzene, enhanced anaerobic bioremediation, stable isotope probing, biosep biotrap
Procedia PDF Downloads 342558 Discrete Element Modeling on Bearing Capacity Problems
Authors: N. Li, Y. M. Cheng
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In this paper, the classical bearing capacity problem is re-considered from discrete element analysis. In the discrete element approach, the bearing capacity problem is considered from the elastic stage to plastic stage to rupture stage (large displacement). The bearing capacity failure mechanism of a strip footing on soil is investigated, and the influence of micro-parameters on the bearing capacity of soil is also observed. It is found that the distinct element method (DEM) gives very good visualized results, and basically coincides well with that derived by the classical methods.Keywords: bearing capacity, distinct element method, failure mechanism, large displacement
Procedia PDF Downloads 366557 Simulation of Red Blood Cells in Complex Micro-Tubes
Authors: Ting Ye, Nhan Phan-Thien, Chwee Teck Lim, Lina Peng, Huixin Shi
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In biofluid flow systems, often the flow problems of fluids of complex structures, such as the flow of red blood cells (RBCs) through complex capillary vessels, need to be considered. In this paper, we aim to apply a particle-based method, Smoothed Dissipative Particle Dynamics (SDPD), to simulate the motion and deformation of RBCs in complex micro-tubes. We first present the theoretical models, including SDPD model, RBC-fluid interaction model, RBC deformation model, RBC aggregation model, and boundary treatment model. After that, we show the verification and validation of these models, by comparing our numerical results with the theoretical, experimental and previously-published numerical results. Finally, we provide some simulation cases, such as the motion and deformation of RBCs in rectangular, cylinder, curved, bifurcated, and constricted micro-tubes, respectively.Keywords: aggregation, deformation, red blood cell, smoothed dissipative particle dynamics
Procedia PDF Downloads 174556 A Survey of Crowdsourcing Technology and Application
Authors: Qianjia Cheng, Hongquan Jiang
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Crowdsourcing solves the problems that computers can't handle by integrating computers and the Internet. Its extensive knowledge sources, high efficiency, and high quality have made crowdsourcing attract wide attention in industry and academia in recent years. The development of online crowdsourcing platforms such as Clickworker, Amazon Mechanical Turk(Mturk) tends to mature gradually. This paper sorts out the concept of crowdsourcing, sorts out the workflow of competitive crowdsourcing, summarizes the related technologies of crowdsourcing based on workflow, quality control, cost control, and delay control, and introduces the typical crowdsourcing platform. Finally, we highlight some open problems of the current crowdsourcing and present some future research directions in this area.Keywords: application, crowdsourcing, crowdsourcing platform, system architecture
Procedia PDF Downloads 91555 Optimization of Wavy Channel Using Genetic Algorithm
Authors: Yue-Tzu Yang, Peng-Jen Chen
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The present study deals with the numerical optimization of wavy channel with the help of genetic algorithm (GA). Three design variables related to the wave amplitude (A), the wavelength (λ) and the channel aspect ratio (α) are chosen and their ranges are decided through preliminary calculations of three-dimensional Navier-stokes and energy equations. A parametric study is also performed to show the effects of different design variables on the overall performance of the wavy channel. Objective functions related to the heat transfer and pressure drop, performance factor (PF) is formulated to analyze the performance of the wavy channel. The numerical results show that the wave amplitude and the channel aspect ratio have significant effects on the thermal performance. It can improve the performance of the wavy channels by increasing wave amplitude or decreasing the channel aspect ratio. Increasing wavelengths have no significant effects on the heat transfer performance.Keywords: wavy channel, genetic algorithm, optimization, numerical simulation
Procedia PDF Downloads 301554 Reflection Performance of Truncated Pyramidal and Truncated Wedge Microwave Absorber Using Sugarcane Bagasse (SCB)
Authors: Liyana Zahid, Mohd Fareq Abd Malek, Ee Meng Cheng, Wei Wen Liu, Yeng Seng Lee, Muhammad Nadeem Iqbal, Fwen Hoon Wee
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One of the parameters that affect the performance of microwave absorbers is the shape of the absorbers. This paper shows the performance (reflection loss) of truncated pyramidal and truncated wedge microwave absorbers in the range frequency between 8.2 to 12.4 GHz (X-Band) in simulation. The material used is sugarcane bagasse (SCB) which is one of the new materials that used to fabricate the microwave absorber. The complex permittivity was measured using Agilent dielectric probe technique. The designs were simulated using CST Microwave Studio Software. The reflection losses between these two shapes were compared.Keywords: microwave absorber, reflection loss, sugarcane bagasse (SCB), X-Band
Procedia PDF Downloads 352553 Combining an Optimized Closed Principal Curve-Based Method and Evolutionary Neural Network for Ultrasound Prostate Segmentation
Authors: Tao Peng, Jing Zhao, Yanqing Xu, Jing Cai
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Due to missing/ambiguous boundaries between the prostate and neighboring structures, the presence of shadow artifacts, as well as the large variability in prostate shapes, ultrasound prostate segmentation is challenging. To handle these issues, this paper develops a hybrid method for ultrasound prostate segmentation by combining an optimized closed principal curve-based method and the evolutionary neural network; the former can fit curves with great curvature and generate a contour composed of line segments connected by sorted vertices, and the latter is used to express an appropriate map function (represented by parameters of evolutionary neural network) for generating the smooth prostate contour to match the ground truth contour. Both qualitative and quantitative experimental results showed that our proposed method obtains accurate and robust performances.Keywords: ultrasound prostate segmentation, optimized closed polygonal segment method, evolutionary neural network, smooth mathematical model, principal curve
Procedia PDF Downloads 204552 Digital Twin Platform for BDS-3 Satellite Navigation Using Digital Twin Intelligent Visualization Technology
Authors: Rundong Li, Peng Wu, Junfeng Zhang, Zhipeng Ren, Chen Yang, Jiahui Gan, Lu Feng, Haibo Tong, Xuemei Xiao, Yuying Chen
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The research of Beidou-3 satellite navigation is on the rise, but in actual work, it is inevitable that satellite data is insecure, research and development is inefficient, and there is no ability to deal with failures in advance. Digital twin technology has obvious advantages in the simulation of life cycle models of aerospace satellite navigation products. In order to meet the increasing demand, this paper builds a Beidou-3 satellite navigation digital twin platform (BDSDTP). The basic establishment of BDSDTP was completed by establishing a digital twin double, Beidou-3 comprehensive digital twin design, predictive maintenance (PdM) mathematical model, and visual interaction design. Finally, this paper provides a time application case of the platform, which provides a reference for the application of BDSDTP in various fields of navigation and provides obvious help for extending the full cycle life of Beidou-3 satellite navigation.Keywords: BDS-3, digital twin, visualization, PdM
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