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2020

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Articles 7591 - 7620 of 10642

Full-Text Articles in Engineering

Comparison Of Signaling Profiles In The Low Dose Range Following Low And High Let Radiation, Deepa M. Sridharan, Lung-Chang Chien, Francis A. Cucinotta, Janice M. Pluth Feb 2020

Comparison Of Signaling Profiles In The Low Dose Range Following Low And High Let Radiation, Deepa M. Sridharan, Lung-Chang Chien, Francis A. Cucinotta, Janice M. Pluth

Environmental & Global Health Faculty Research

During space travel astronauts will be exposed to a very low, mixed field of radiation containing different high LET particles of varying energies, over an extended period. Thus, defining how human cells respond to these complex low dose exposures is important in ascertaining risk. In the current study, we have chosen to investigate how low doses of three different ion's at various energies uniquely change the kinetics of three different phospho-proteins. A normal hTERT immortalized fibroblast cell line, 82–6, was exposed to a range of lower doses (0.05–0.5 Gy) of radiation of different qualities and energies (Si 1000 MeV/u, Si …


Bone Marrow-Derived And Elicited Peritoneal Macrophages Are Not Created Equal: The Questions Asked Dictate The Cell Type Used, Cheryl M. Zajd, Alexis M. Ziemba, Grace M. Miralles, Terry Nguyen, Paul J. Feustel, Stanley M. Dunn, Ryan J. Gilbert, Michelle R. Lennartz Feb 2020

Bone Marrow-Derived And Elicited Peritoneal Macrophages Are Not Created Equal: The Questions Asked Dictate The Cell Type Used, Cheryl M. Zajd, Alexis M. Ziemba, Grace M. Miralles, Terry Nguyen, Paul J. Feustel, Stanley M. Dunn, Ryan J. Gilbert, Michelle R. Lennartz

Chemical and Biochemical Engineering Faculty Research & Creative Works

Macrophages are a heterogeneous and plastic population of cells whose phenotype changes in response to their environment. Macrophage biologists utilize peritoneal (pMAC) and bone marrow-derived macrophages (BMDM) for in vitro studies. Given that pMACs mature in vivo while BMDM are ex vivo differentiated from stem cells, it is likely that their responses differ under experimental conditions. Surprisingly little is known about how BMDM and pMACs responses compare under the same experimental conditionals. While morphologically similar with respect to forward and side scatter by flow cytometry, reports in the literature suggest that pMACs are more mature than their BMDM counterparts. Given …


Anomalous Eutectic Microstructures In Mg–Al Structural Alloy Prepared By Rapid Solidification, Soodabeh Azadehranjbar, Jian Wang, Jeffrey E. Shield Feb 2020

Anomalous Eutectic Microstructures In Mg–Al Structural Alloy Prepared By Rapid Solidification, Soodabeh Azadehranjbar, Jian Wang, Jeffrey E. Shield

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Magnesium is the lightest engineering metal 1 However, conventional Mg alloys typically suffer from low strength and poor deformability due to very few slip systems and easy twinning 3 Alloying Mg with other materials and microstructural engineering are promising approaches to increase ductility and strength of Mg In the current work, non equilibrium solidification conditions were applied to induce a transition from regular to anomalous eutectic in Mg Al eutectic alloy such that four distinguished microstructures were acquired and the corresponding formation mechanisms were investigated


Working Across Disciplines And Library Units To Develop A Suite Of Systematic Review Services For Researchers, Nedelina Tchangalova, Eileen G. Harrington, Stephanie Ritchie, Sarah Over, Jodi Coalter Feb 2020

Working Across Disciplines And Library Units To Develop A Suite Of Systematic Review Services For Researchers, Nedelina Tchangalova, Eileen G. Harrington, Stephanie Ritchie, Sarah Over, Jodi Coalter

Collaborative Librarianship

Since their inception in the health sciences field, systematic reviews have expanded into many other subject disciplines. To address this growing need, subject librarians at the University of Maryland Libraries collaborated on a pilot program in three phases to introduce researchers to the process of conducting systematic and scoping reviews. This article describes the development of various collaborative efforts leading to the implementation of a systematic review service based on participant feedback. Assessment and evaluation techniques are shared to encourage further refinement of the systematic review service.


Lung Nodule Malignancy Prediction From Computed Tomography Images Using Deep Learning, Rahul Paul Feb 2020

Lung Nodule Malignancy Prediction From Computed Tomography Images Using Deep Learning, Rahul Paul

USF Tampa Graduate Theses and Dissertations

Lung cancer has a high incidence and mortality rate. The five-year relative survival rate for all lung cancers is 18%. Due to the high mortality and incidence rate of lung cancer worldwide, early detection is essential. Low dose Computed Tomography (CT) is a commonly used technique for screening, diagnosis, and prognosis of non-small cell lung cancer (NSCLC). The National Lung Screening Trial (NLST) compared low-dose helical computed tomography (LDCT) and standard chest radiography (CXR) for three annual screens and reported a 20% relative reduction in lung cancer mortality for LDCT compared to CXR. As such, LDCT screening for lung cancer …


Initial Development Of Corn Seedlings After Seed Priming With Nanoscale Synthetic Zinc Oxide, Michel Esper Neto, David W. Britt, Lorena Moreira Lara, Anthony Cartwright, Rayssa Fernanda De Santos, Tadeu Takeyoshi Inoue, Marcelo Augusto Batista Feb 2020

Initial Development Of Corn Seedlings After Seed Priming With Nanoscale Synthetic Zinc Oxide, Michel Esper Neto, David W. Britt, Lorena Moreira Lara, Anthony Cartwright, Rayssa Fernanda De Santos, Tadeu Takeyoshi Inoue, Marcelo Augusto Batista

Biological Engineering Faculty Publications

Nanofertilizers are increasingly explored for sustainable micronutrient delivery in agriculture. Pre-treating seeds with nanofertilizers prior to planting (i.e., seed priming) reduces concerns about nanoparticle (NP) fertilizer non-target dispersion; however, priming formulations and concentrations must be carefully selected to avoid germination inhibition and toxicity. Here we investigate changes in corn seed germination and seedling development after seed priming with ZnO NPs, ZnO bulk and ZnCl2. To evaluate the effects sterile seeds were immersed in priming solutions of 0, 20, 40, 80, 160 mg L−1 Zn for the three Zn sources. Following an 8 h priming the seeds were …


Electrocoagulation: A Promising Method To Treat And Reuse Mineral Processing Wastewater With High Cod, Gaogui Jing, Shuai Ren, Yuesheng Gao, Wei Sun, Zhiyong Gao Feb 2020

Electrocoagulation: A Promising Method To Treat And Reuse Mineral Processing Wastewater With High Cod, Gaogui Jing, Shuai Ren, Yuesheng Gao, Wei Sun, Zhiyong Gao

Michigan Tech Publications, Part 1

Mineral processing wastewater contains large amounts of reagents which can lead to severe environmental problems, such as high chemical oxygen demand (COD). Inspired by the wastewater treatment in such industries as those of textiles, food, and petrochemistry, in the present work, electrocoagulation (EC) is applied for the first time to explore its feasibility in the treatment of wastewater with an initial COD of 424.29 mg/L from a Pb/Zn sulfide mineral flotation plant and its effect on water reuse. Typical parameters, such as anode materials, current density, initial pH, and additives, were characterized to evaluate the performance of the EC method. …


Architecture And Trilogy Of (Law, Theory And Hypothesis), Ahmed Hashim Hameed Feb 2020

Architecture And Trilogy Of (Law, Theory And Hypothesis), Ahmed Hashim Hameed

Al-Esraa University College Journal for Engineering Sciences

The general cognitive expositions had focused on the study of the general knowledge frameworks of the field of architecture, with both concepts that influencing and influenced by them, which used to contain them without referring to their intellectual origins in order to understand their general effect and their role in the cognitive enrichment to the architectural field. This, in return, showed the importance of direction to study the role, influence and effect of trilogy (Law, theory and hypothesis) in the field of architecture, according to their general reality knowledge and their specific theoretical and intellectual characteristics. This research deals with …


The Impact Of Spatial Location Of Functions To Identify Architectural Forms As A Landmark (Case Study - Contemporary Islamic Architecture -), Ibtisam Abdulelah Mohammed Al Khafaji, Maha Haki Ismaeil Feb 2020

The Impact Of Spatial Location Of Functions To Identify Architectural Forms As A Landmark (Case Study - Contemporary Islamic Architecture -), Ibtisam Abdulelah Mohammed Al Khafaji, Maha Haki Ismaeil

Al-Esraa University College Journal for Engineering Sciences

This research discusses the impact of spatial location of functions inside architectural form to enhance visual legibility and how it can improve the possibilities of identifying them as a landmark. The absence of a clear conceptual frame which can be used to describe this impact forms the basic research problem. The objective aim of the research is to clarify and describe this impact. To achieve this objective aim, an analytical process was used. We supposed that spatial location of functions enhances visual legibility of forms, then improves our possibility of identifying them as a landmark. For applying the conceptual frame, …


Effect Of Loading Level Of Hybrid Reinforced Concrete Deep Beams Under Repeated Loading, Sawsan Akram Hassan, Ghsoon Ali Faroun Feb 2020

Effect Of Loading Level Of Hybrid Reinforced Concrete Deep Beams Under Repeated Loading, Sawsan Akram Hassan, Ghsoon Ali Faroun

Al-Esraa University College Journal for Engineering Sciences

This research is devoted to investigating the experimental and theoretical behavior of hybrid deep beams under monotonic and repeated two-point loading. The dimensions and the flexural reinforcement of the deep beams were kept constant. In this work, the idea of a hybrid beam is completely different. Two types of concrete were used but not in the cross-section. The first type, which is fiberous concrete (FC), was used in casting beam sides (shear spans), while the second type was conventional concrete (CC) which was used in the middle portion of the beam (between two shear spans). This was done to strengthen …


Reverse Osmosis Method For Sulphate Re-Moval From Treated Wastewater Of Al-Doura Refinery, Rana Mohammed Rasheed Feb 2020

Reverse Osmosis Method For Sulphate Re-Moval From Treated Wastewater Of Al-Doura Refinery, Rana Mohammed Rasheed

Al-Esraa University College Journal for Engineering Sciences

The treated wastewater by the industrial Wastewater Treatment Plant (WWTP) commonly named (INGECO) in Al-Doura refinery suffers from highly sulfate concentrations that exceed the EPA specified limits of 250 mg/L. Therefore, laboratory water quality historical data have been reviewed and analyzed to determine the annual rate, maximum, and peak sulfate concentrations that were found to be 360 mg/L, 425 mg/L, and 550 mg/L, respectively. Through field inspection aimed at specifying the reasons for the high sulfate concentrations in the wastewater of most refinery process units, it was found that the maximum required sulfate remaining concentration should not exceed 10 mg/L …


Comparison Between Regular And Irregular Configuration In Earthquake Resistant Design, Ali Nur-Aldeen Azeez, Ali Mohsen Jaafer Al-Khafaji Feb 2020

Comparison Between Regular And Irregular Configuration In Earthquake Resistant Design, Ali Nur-Aldeen Azeez, Ali Mohsen Jaafer Al-Khafaji

Al-Esraa University College Journal for Engineering Sciences

Earthquake-resistant design is one of the greatest challenges that must be considered by the Architect because it is a serious natural disaster that affects the stability and durability of the building. Due to the connection between the seismic behavior of buildings with its formal configuration and the differences in seismic resistance between regular and irregular buildings, the research problem presented as the confusion of seismic behavior of irregular buildings and their difference from the regular buildings when earthquakes occur. The aim of the research is to clarify the differences between regular and irregular configurations, also clarifying the design considerations in …


Pedestrian Movement Within Residential Areas, Abd Alali Hamza Mohamed Feb 2020

Pedestrian Movement Within Residential Areas, Abd Alali Hamza Mohamed

Al-Esraa University College Journal for Engineering Sciences

The network of transport within residential areas, especially within residential neighborhoods, consists mainly of roads designed to provide relative safety for road users and to prioritize solutions that enhance safety. It is believed that the pedestrian movement network should be separated from the car movement network, with a focus on road design, pedestrian paths, and the types of vehicles used in these areas to ensure safety. This research explores the solutions developed in the planning of roads and walkways in traditional housing schemes within the urban fabric of old cities. It examines the approaches and conclusions of modern models of …


Low-Grade Kaolin Clay Natural Resource For Use As A Supplementary Cementitious Material In Structural Concrete Elements, Brandon X. Lorentz Feb 2020

Low-Grade Kaolin Clay Natural Resource For Use As A Supplementary Cementitious Material In Structural Concrete Elements, Brandon X. Lorentz

USF Tampa Graduate Theses and Dissertations

At the turn of the century, low-grade kaolin clay (LGK) was presented as a widely available and potential natural resource of supplementary cementitious materials (SCM) for producing high performance concretes. In using LGK as an SCM, clinker production is reduced, aiding environmental concerns with associated CO2 emissions. These types of clays have very heterogeneous mineralogy and microstructural characteristics, causing unique influences on concrete structural and flow performance, although these influences are not well understood. This research studies LGK natural to the state of Florida and assesses their potential use as high performance SCM.

Ten kaolin clays were obtained through a …


Analysis Of Identification Method For Bacterial Species And Antibiotic Resistance Genes Using Optical Data From Dna Oligomers, Ryan L. Wood, Tanner Jensen, Cindi Wadsworth, Mark Clement, Prashant Nagpal, William G. Pitt Feb 2020

Analysis Of Identification Method For Bacterial Species And Antibiotic Resistance Genes Using Optical Data From Dna Oligomers, Ryan L. Wood, Tanner Jensen, Cindi Wadsworth, Mark Clement, Prashant Nagpal, William G. Pitt

Faculty Publications

Bacterial antibiotic resistance is becoming a significant health threat, and rapid identification of antibiotic-resistant bacteria is essential to save lives and reduce the spread of antibiotic resistance. This paper analyzes the ability of machine learning algorithms (MLAs) to process data from a novel spectroscopic diagnostic device to identify antibiotic-resistant genes and bacterial species by comparison to available bacterial DNA sequences. Simulation results show that the algorithms attain from 92% accuracy (for genes) up to 99% accuracy (for species). This novel approach identifies genes and species by optically reading the percentage of A, C, G, T bases in 1000s of short …


Analysis Of Identification Method For Bacterial Species And Antibiotic Resistance Genes Using Optical Data From Dna Oligomers, Ryan L. Wood, Tanner Jensen, Cindi Wadsworth, Mark Clement, Prashant Nagpal, William G. Pitt Feb 2020

Analysis Of Identification Method For Bacterial Species And Antibiotic Resistance Genes Using Optical Data From Dna Oligomers, Ryan L. Wood, Tanner Jensen, Cindi Wadsworth, Mark Clement, Prashant Nagpal, William G. Pitt

Faculty Publications

Bacterial antibiotic resistance is becoming a significant health threat, and rapid identification of antibiotic-resistant bacteria is essential to save lives and reduce the spread of antibiotic resistance. This paper analyzes the ability of machine learning algorithms (MLAs) to process data from a novel spectroscopic diagnostic device to identify antibiotic-resistant genes and bacterial species by comparison to available bacterial DNA sequences. Simulation results show that the algorithms attain from 92% accuracy (for genes) up to 99% accuracy (for species). This novel approach identifies genes and species by optically reading the percentage of A, C, G, T bases in 1000s of short …


Sustainable, Alginate-Based Sensor For Detection Of Escherichia Coli In Human Breast Milk, Nicholas Kikuchi, Margaret May, Matthew Zweber, Jerard Madamba, Craig M. Stephens, Unyoung Kim, Maryam Mobed-Miremadi Feb 2020

Sustainable, Alginate-Based Sensor For Detection Of Escherichia Coli In Human Breast Milk, Nicholas Kikuchi, Margaret May, Matthew Zweber, Jerard Madamba, Craig M. Stephens, Unyoung Kim, Maryam Mobed-Miremadi

Bioengineering

There are no existing affordable diagnostics for sensitive, rapid, and on-site detection of pathogens in milk. To this end, an on-site colorimetric-based sustainable assay has been developed and optimized using an L16 (54) Taguchi design to obtain results in hours without PCR amplification. To determine the level of Escherichia coli (E. coli) contamination, after induction with 150 µL of breast milk, the B-Per bacterial protein extraction kit was added to a solution containing an alginate-based microcapsule assay. Within this 3 mm spherical novel sensor design, X-Gal (5-Bromo-4-Chloro-3-Indolyl β-D-Galactopyranoside) was entrapped at a concentration of 2 …


Demand Forecasting Of Wartime Spares Based On Evidence Theory, Yunjing Zhang, Xinxin Wang, Wang Yang, Guangming Tang Feb 2020

Demand Forecasting Of Wartime Spares Based On Evidence Theory, Yunjing Zhang, Xinxin Wang, Wang Yang, Guangming Tang

Journal of System Simulation

Abstract: A new method based on evidence theory is proposed to solve the lack of data for the demand prediction of spares in wartime. Utilizing Markov chain model to research the rule of spares demand of peacetime from the historical data. A Markov chain transfer probability adjustment strategy, based on the change of combat intensity, is designed, which can be used to simulation the rule of spares demand in wartime. Under the experience of experts and the combination of the Fuzzy theory and evidence theory, the spares demand is wartime is forecasted. The simulation example shows that the …


Moea/D Algorithm Based On The Hybrid Framework For Multi-Objective Evolutionary Algorithm, Hongjun Tian, Wang Lei, Qidi Wu Feb 2020

Moea/D Algorithm Based On The Hybrid Framework For Multi-Objective Evolutionary Algorithm, Hongjun Tian, Wang Lei, Qidi Wu

Journal of System Simulation

Abstract: Aimto the difficulties of designing the bonding mechanism of global optimization algorithm and local search strategy for hybrid multi-objective evolutionary algorithm, and of improving the performance of multi-objective evolutionary algorithms, based on the feedback control idea, a systematic and modular hybrid MOEA/D algorithm combining the global optimization and local search is proposed. In the algorithm, a diversity measure method based on crowded entropy is designed; a local search strategy based on simplified quadratic approximation and population diversity enhancement strategy for MOEA/D is proposed. The numerical experiments show that the proposed HMOEA/D can achieve a balance between diversity …


Tele-Robot Control System With Online Virtual Simulation Prediction, Lingyan Hu, Kangbai Shi, Bichun Zhang, Shaoping Xu Feb 2020

Tele-Robot Control System With Online Virtual Simulation Prediction, Lingyan Hu, Kangbai Shi, Bichun Zhang, Shaoping Xu

Journal of System Simulation

Abstract: When a tele-robot with virtual simulation system works in a complicated environment, the virtual scene may not synchronize with the real one. This may cause the operator on the master side to give wrong instruction. This paper presents a tele-robot with online virtual model correction. The virtual simulation system on the master side builds a virtual model of environment and robot on the slave side. It predicts the motion of the slave robot in real time according the commands from the operator. In order to ensure the virtual scene synchronize with the real one, the measured data on the …


Research On Cavitation Evolution Model In Venturi Tube, Guihua Han, Yanan Liu, Junpeng Shao, Cijun Zhang Feb 2020

Research On Cavitation Evolution Model In Venturi Tube, Guihua Han, Yanan Liu, Junpeng Shao, Cijun Zhang

Journal of System Simulation

Abstract: The dynamic cavitation model of venturi tube air-water two-phase flow was established according to the time variation of air precipitation and digestion process in water. FLUENT three-dimension numerical simulation were studied to simulate the air-water two-phase flow, and the variation law of venturi tube throat diameter and inlet pressure on vapor volume fraction were obtained. The results of numerical simulation and experiments show that the vapor volume fraction increases following the increase of the inlet pressure. If the throat diameter is increased, the inlet pressure can be increased as the compensation to achieve the same cavitation effect. The …


Self-Organizing Aggregation Behavior Modeling Of Swarm Robots Based On Ant Colony Algorithm, Yang Wei, Zeng Liang, Xinchen Kang Feb 2020

Self-Organizing Aggregation Behavior Modeling Of Swarm Robots Based On Ant Colony Algorithm, Yang Wei, Zeng Liang, Xinchen Kang

Journal of System Simulation

Abstract: Aiming at the formation of aggregation behavior model of swarm robots, a self-organizing motion model based on particle system mechanics and perceptual state weighting is established to realize the autonomous transfer of robot motion state. The aggregation degree and uniformity index of aggregation behavior are established, and the aggregation performances of different models are analyzed by experiment, which lay a foundation for the formation of self-organized aggregation behavior model of swarm robots. Using the selected model, the self-organizing aggregation behavior simulation experiments are conducted in two cases with boundary constraints and no boundary constraints. The maximum coverage of …


Auv Vertical Plane Control Based On Improved Pid Neural Network Algorithm, Runan Huang, Ding Ning Feb 2020

Auv Vertical Plane Control Based On Improved Pid Neural Network Algorithm, Runan Huang, Ding Ning

Journal of System Simulation

Abstract: An improved PID neural network controller is designed for the movement control of a small low-speed autonomous underwater vehicle (AUV) in vertical plane, and the global control of the depth and pitch angle of the underwater vehicle in vertical plane is obtained. The AUV simulation control system is built by using REMUS underwater vehicle model in Simulink. The simulation results show that the improved control method with better dynamic performance has solved the original excessive saturation issue, and can adapt to different learning rates and network initial weight,and is of certain reference value to the practical application …


Integrated Simulation Test Platform For Environment Perception And Planning Decision Of Intelligent Vehicle, Sun Jian, Runhan Huang, Li Lin, Qiyuan Liu, Yudi Li Feb 2020

Integrated Simulation Test Platform For Environment Perception And Planning Decision Of Intelligent Vehicle, Sun Jian, Runhan Huang, Li Lin, Qiyuan Liu, Yudi Li

Journal of System Simulation

Abstract: The simplicity of testing modules and the lack of high-fidelity and high-density traffic scenes are the primary issues in the intelligent vehicle' simulation test. To solve these problems, a "software in the loop" integration test platform is built. The environmental perception module is integrated on the basis of the PreScan, the planning decision-making module designed by MATLAB/Simulink and the virtual traffic flow environment from Vissim. Based on this platform, high-fidelity traffic flow scenes can be generated rapidly to support the test of environment perception and decision-making integratedly and effectively. Moreover, the intelligent vehicle's influence on the traffic flow …


Research On Motion Cueing Algorithm Based On Vr Motion Simulator, Xiaolu Li, Jianfeng Yan, Cangsu Xu, Zongming Wu, Yuanhui Zhang, Junjiang Zhu Feb 2020

Research On Motion Cueing Algorithm Based On Vr Motion Simulator, Xiaolu Li, Jianfeng Yan, Cangsu Xu, Zongming Wu, Yuanhui Zhang, Junjiang Zhu

Journal of System Simulation

Abstract: Aiming at the phase delay and the false suggest of the classical motion-sensing simulation algorithm in VR motion simulator that lead to insufficient consistency between virtual and real movement and cause VR motion sickness disease, an improved motion-sensing simulation algorithm is proposed. Based on the classical simulation algorithm, the algorithm compromises the vestibular sensory system, feeds back the output error, and applies the fuzzy control algorithm to modify and forecast the input acceleration and angular velocity. This improved motion-sensing simulation algorithm is trained in the condition of virtual choppy terrain. The MATLAB/Simulink simulation results show that the improved motion-sensing …


Cascade Transmission Evaluation Of Ecosystem Damage Caused By Dust Migration, Guangqiu Huang, He Tong, Qiuqin Lu Feb 2020

Cascade Transmission Evaluation Of Ecosystem Damage Caused By Dust Migration, Guangqiu Huang, He Tong, Qiuqin Lu

Journal of System Simulation

Abstract: To solve the cascade transmission evaluation of ecosystem damage caused by dust migration in mining area, the migration network is constructed by dust migration path, and the potential hazard source path is identified. The definition of Petri-net simulation model of ecosystem damage with cascade propagation (PN-EDCP) is given, and the general method of abstracting migration paths network into a Petri net model is expounded. By introducing the concepts of attributes and methods of place objects into Petri net model, the real meaning of the model is clear, and the ability of describing and analyzing the logical relationship between ecosystem …


Control Improvement And Simulation Of Dfig Under Power Grid Failure, Hongyang Zhang, Zhentang Shi, Zhifeng Zhang Feb 2020

Control Improvement And Simulation Of Dfig Under Power Grid Failure, Hongyang Zhang, Zhentang Shi, Zhifeng Zhang

Journal of System Simulation

Abstract: Following the increasing scale of installed wind power, the wind turbines, as an important part of the future energy internet, its ability to cope with the fault of the power grid becomes more and more important. Aiming at the transient characteristics of doubly fed induction generator (DFIG) under power grid fault, a comprehensive control strategy, based on the classification of power grid faults, the optimization of controller parameters and auxiliary equipments, is proposed. Compared with the traditional control method, the large control error and response lag is overcome, and the fine control is realized. Based on MATLAB and VC++ …


Shielding Modeling And Simulation Of Coastal Building To Vts Radar, Chunhui Zhou, Zhou Ling, Langxiong Gan, Xiaodong Cheng, Junjie Gao Feb 2020

Shielding Modeling And Simulation Of Coastal Building To Vts Radar, Chunhui Zhou, Zhou Ling, Langxiong Gan, Xiaodong Cheng, Junjie Gao

Journal of System Simulation

Abstract: In order to study the shielding influence of coastal building on the VTS radar, a mathematical expression model of shielding area is proposed. The expression model are divided into finite continuous 3D shielding area, infinite continuous 3D shielding area, finite discontinuous 3D shielding area and infinite discontinuous 3D shielding area. The range and height of the shielding area are calculated, according to the expression model and spatial geometric relation. In addition, 3ds MAX is used in the modeling and simulation of shielding area. Taking the influence of Prince's Bay Cruise Terminal Building on the radar Shekou radar as an …


Interference Management Mechanism In Next Generation Dense Wlan, Ronghui Hou, Xiaoyao Ma, Liu Yi, Hongyan Li Feb 2020

Interference Management Mechanism In Next Generation Dense Wlan, Ronghui Hou, Xiaoyao Ma, Liu Yi, Hongyan Li

Journal of System Simulation

Abstract: Aiming at the unfairness and low throughput in a wireless local area network with dense access points and terminals deployment, a user-centered resource allocation method which can configure the specific channel and power level for each user is proposed. This method can maximize the network throughput while ensuring the minimum throughput requirement for each user. The proposed interference management mechanism and user identification method can be easily implemented in the current wireless local area network system. Simulation results show that the proposed resource allocation scheme enhances about 47.3% throughput to a basic service set. In particular, 190% improvement can …


Cuckoo Search Algorithm With Dynamic Step And Discovery Probability, Jingsen Liu, Xiaozhen Liu, Li Yu Feb 2020

Cuckoo Search Algorithm With Dynamic Step And Discovery Probability, Jingsen Liu, Xiaozhen Liu, Li Yu

Journal of System Simulation

Abstract: In order to further improve the low accuracy and slow convergence speed of algorithm search, a cuckoo search algorithm with dynamic step size and probability of discovery is proposed. The algorithm dynamically constrains the Levy's moving step of each generation by introducing the step adjustment factor, which makes the Levy's flight mechanism adaptive. In the probability of finding, the random inertia weight with uniform distribution and F distribution is used to change the fixed value of the probability of discovery, to strengthen the diversity of the population and to keep the balance between global search and local exploration. The …