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Articles 53701 - 53730 of 302598

Full-Text Articles in Physical Sciences and Mathematics

Short-Term Power Load Forecasting Based On Lstm Neural Network Optimized By Improved Pso, Tengfei Wei, Tinglong Pan Aug 2021

Short-Term Power Load Forecasting Based On Lstm Neural Network Optimized By Improved Pso, Tengfei Wei, Tinglong Pan

Journal of System Simulation

Abstract: To improve the accuracy of short-term power load forecasting, a short-term power load forecasting model (ACMPSO-LSTM) based on long-short memory neural network (LSTM) optimized by adaptive Cauchy mutation particle swarm optimization (ACMPSO) is proposed. For the problem of difficult selection of LSTM model parameters, ACMPSO is used to optimize model parameters, and non-linear changing inertia weights are adopted to improve the global optimization ability and convergence speed of PSO algorithm. In the optimization process, a mutation operation based on genetic algorithm is added to reduce the risk of particles falling into local optimal solutions. The simulation results show that …


Relationship Between Suspension Damping And Stability Of Vehicle Hunting Motion, Yan Yong, Zeng Jing, Kun Xu, Feiyan Zhao Aug 2021

Relationship Between Suspension Damping And Stability Of Vehicle Hunting Motion, Yan Yong, Zeng Jing, Kun Xu, Feiyan Zhao

Journal of System Simulation

Abstract: In order to avoid or restrain the primary hunting stability of rail vehicles, correlation between the primary hunting stability and suspension damping parameters under the damping ratio of 0 and 5% is calculated based on the analysis of suspension parameters on the vehicle modal frequency. The method to improve the stability of vehicle hunting motion by optimizing suspension parameters is obtained. The results show that when selecting different damping ratios to calculate the critical stability, the range of damping parameters varies greatly. The lateral damping parameter in a certain range or a larger vertical damping is beneficial to keep …


Modeling On Anti-Uav System-Of-Systems Combat Ooda Loop Based On Netlogo, Zhao Zhu, Wang Yi, Ruifeng Fan, Liya Li, Qi Meng Aug 2021

Modeling On Anti-Uav System-Of-Systems Combat Ooda Loop Based On Netlogo, Zhao Zhu, Wang Yi, Ruifeng Fan, Liya Li, Qi Meng

Journal of System Simulation

Abstract: Aiming at the threats from unmanned aerial vehicle (UAV) or swarm, as well as the difficult problems of systems confrontation modeling, overall process design, and operational effectiveness evaluation in anti-UAV system-of-systems, the structure and operational process both of the UAV and anti-UAV systems are analyzed respectively, and the anti-UAV Observe-Orient-Decide-Act (OODA) system-of-systems combat model which based on multi-agent modeling platform NetLogo is proposed. Utilizing the emergence of agent role in this simulation model, the influence exerted by OODA on anti-UAV is studied by the multi-agent simulation. The results show that the OODA loop is one …


Data From: Yellow Air Day Advisory Study, Arthur J. Caplan Aug 2021

Data From: Yellow Air Day Advisory Study, Arthur J. Caplan

Browse all Datasets

Using a dataset consisting of daily vehicle trips, PM2.5 concentrations, along with a host of climactic control variables, we test the hypothesis that “yellow air day” advisories provided by the Utah Division of Air Quality resulted in subsequent reductions in vehicle trips taken during northern Utah’s winter-inversion seasons in the early 2000s. Winter inversions occur in northern Utah when climactic conditions are such that PM2.5 concentrations (derived mainly from vehicle emissions) become trapped in the lower atmosphere, leading to unhealthy air quality (concentrations of at least 35 µg/m3) over a span of what are called “red air days”. When concentrations …


The Challenges Of Applying Computational Legal Analysis To Mhealth Security And Privacy Regulations, Brian Tung Aug 2021

The Challenges Of Applying Computational Legal Analysis To Mhealth Security And Privacy Regulations, Brian Tung

McKelvey School of Engineering Theses & Dissertations

As our world has grown in complexity, so have our laws. By one measure, the United States Code has grown over 30x as long since 1935, and the 186,000-page Code of Federal Regulations has grown almost 10x in length since 1938. Our growing legal system is too complicated; it’s impossible for people to know all the laws that apply to them. However, people are still subject to the law, even if they are unfamiliar with it. Therein lies the need for computational legal analysis. Tools of computation (e.g., data visualization, algorithms, and artificial intelligence) have the potential to transform civic …


Research On Hybrid Deployment Strategy And Model For Key Position Air-Defense Based On Multi-Weapon Platforms, Jiaqing Wan, Pengfei Wang, Junlin Tang, Zhang Dong, Xinguo Li Aug 2021

Research On Hybrid Deployment Strategy And Model For Key Position Air-Defense Based On Multi-Weapon Platforms, Jiaqing Wan, Pengfei Wang, Junlin Tang, Zhang Dong, Xinguo Li

Journal of System Simulation

Abstract: Multi-platform cooperative air-defense is the development direction of air-defense and antimissile warfare, and the hybrid deployment strategy and model are the important research content. Based on the background of key position air-defense research, the deployment strategy, principle and form of multi-platform cooperative air-defense are studied. The operational scenario and operational process of typical air defense are established. The principles, influencing factors and deployment methods of hybrid deployment are studied. A typical hybrid deployment strategy is proposed and a mathematical model is established. It provides support for the multi platform cooperative air defense and key position defense deployment.


Self-Learning-Based Multiple Spacecraft Evasion Decision Making Simulation Under Sparse Reward Condition, Zhao Yu, Jifeng Guo, Yan Peng, Chengchao Bai Aug 2021

Self-Learning-Based Multiple Spacecraft Evasion Decision Making Simulation Under Sparse Reward Condition, Zhao Yu, Jifeng Guo, Yan Peng, Chengchao Bai

Journal of System Simulation

Abstract: In order to improve the ability of spacecraft formation to evade multiple interceptors, aiming at the low success rate of traditional procedural maneuver evasion, a multi-agent cooperative autonomous decision-making algorithm, which is based on deep reinforcement learning method, is proposed. Based on the actor-critic architecture, a multi-agent reinforcement learning algorithm is designed, in which a weighted linear fitting method is proposed to solve the reliability allocation problem of the self-learning system. To solve the sparse reward problem in task scenario, a sparse reward reinforcement learning method based on inverse value method is proposed. According to the task scenario, …


A Signal Decomposition Method Based On Multi-Layer Iteration Structured Singular Spectrum Analysis, Yumiao Wei, Zhili Zhang, Hongguang Li, Shuqing Li Aug 2021

A Signal Decomposition Method Based On Multi-Layer Iteration Structured Singular Spectrum Analysis, Yumiao Wei, Zhili Zhang, Hongguang Li, Shuqing Li

Journal of System Simulation

Abstract: To process the complex signals with concentrated frequency distribution, an adaptive decomposition method based on singular spectrum analysis with multi-layer iteration structure is researched. The traditional singular spectrum analysis is improved by frequency band subdivision and iterative filtering approach. A high-precision decomposition algorithm base on recursive structure is therefore designed, solving the problems such as insufficient adaptive capability and unsatisfied decomposition. Simulation results show that adaptive decomposition capability of the proposed method is effectively enhanced. For the multi-mode vibration signal with 0.2% ratio of spitting frequency to center frequency, the components are all accurately extracted, and consistent well …


Simulation Analysis Of Assessment Method For Missile Accuracy, Shuqing Li, Zhili Zhang, Yumiao Wei, Haitao Wang Aug 2021

Simulation Analysis Of Assessment Method For Missile Accuracy, Shuqing Li, Zhili Zhang, Yumiao Wei, Haitao Wang

Journal of System Simulation

Abstract: The missile accuracy of the falling points is one of the important performance indexes of missile systems, so the assessment method is very important. An improved algorithm for missile accuracy assessment is proposed. Accuracy assessment problem is simplified as a hypothesis check for probability circle, and the accuracy difference coefficients are defined to describe the accuracy difference between the real falling points and the expected situation. Based on the probability circle method, an improved risk assessment method is put forward to balance and minimize producer's risk and consumer's risk. According to sequential check method, this risk assessment …


Obstacle Avoidance Path Planning Of Bridge Crane Based On Improved Rrt Algorithm, Zhimei Chen, Li Min, Xuejuan Shao, Zhicheng Zhao Aug 2021

Obstacle Avoidance Path Planning Of Bridge Crane Based On Improved Rrt Algorithm, Zhimei Chen, Li Min, Xuejuan Shao, Zhicheng Zhao

Journal of System Simulation

Abstract: In view of the problem that the reasonable path can not be obtained quickly for bridge crane planning in complex environment, a rapidly exploring random tree (RRT) algorithm combined with particle swarm algorithm is proposed. According to the characteristics of the bridge crane operation, the RRT algorithm is improved. The two-way RRT algorithm is used to make the tree grow in the direction of the target according to the probability. When the path is generated, the particle swarm optimization algorithm is used to smooth the path to get a more suitable path for the operation of the bridge crane. …


Actuator Fault Status Evaluation Based On Two-Class Nmf Network, Yinsong Wang, Tianshu Sun Aug 2021

Actuator Fault Status Evaluation Based On Two-Class Nmf Network, Yinsong Wang, Tianshu Sun

Journal of System Simulation

Abstract: In the feedback control loop, the adjustment ability of controller covers up the performance degradation of the actuator to some degree. A fault state evaluation algorithm based on a two-class non-negative matrix network is proposed to implement online fault state monitoring of the actuator, including fault classification and degradation assessment. The local static features of the samples are extracted, and a classifier model is established to form a network. The similarity is introduced to describe the dynamic characteristics between samples. To fulfill the actuator fault status assessment, the static distance and dynamic changes of the network output are merged …


Research And Application Of Simulation Support Platform For System-Of-Systems Combat, Xiaodong Huang, Kongshu Xie, Li Ni, Xuefeng Yan, Yali Zhao Aug 2021

Research And Application Of Simulation Support Platform For System-Of-Systems Combat, Xiaodong Huang, Kongshu Xie, Li Ni, Xuefeng Yan, Yali Zhao

Journal of System Simulation

Abstract: Based on the requirement of developing high-precision, high-reliability, and high-fidelity SoS (System-of-Systems) combat simulation system efficiently, the overall structure of SoS combat simulation platform is designed with the implementation process of the SoS simulation development as the starting point. The key methods such as the parameterized & serviced SoS simulation framework, SoS combat oriented multi-view collaborative modeling, extensible high-performance distributed parallel simulation, and intelligent simulation evaluation based on large data & deep learning are emphatically put forward and implemented. A simulation platform is developed to support the weapon equipment SoS combat simulation deduction and evaluation in complex environment. Applications …


Research On Integrated Optimization Approach For Car-Sharing Systems, Tang Jie, Jinxin Cao Aug 2021

Research On Integrated Optimization Approach For Car-Sharing Systems, Tang Jie, Jinxin Cao

Journal of System Simulation

Abstract: Effective scheduling and routing of employees and vehicles determines the efficiency of car-sharing systems. Aiming at the scheduling of shared cars within one day, with the objective of minimizing the total system costs and personnel costs, a bi-level optimization model for multiple traveling salesman problem with time windows is established. A genetic algorithm with multi-chromosome coding and the optimized complex mutation operator are developed for the problem solution. From the comprehensive computational experiments, it can be concluded that the total numbers of vehicles and employees with the joint routing plans satisfying the order constraints can be obtained in …


Residential Demand Response Scheduling Optimization And Simulation Based On An Improved Pso Algorithm, Huazhen Li, Youquan Liu, Jiawei Zhu, Liao Qiang Aug 2021

Residential Demand Response Scheduling Optimization And Simulation Based On An Improved Pso Algorithm, Huazhen Li, Youquan Liu, Jiawei Zhu, Liao Qiang

Journal of System Simulation

Abstract: Aiming at the problems of low utilization rate of household load energy and the potential damage to the power grid caused by the lack of systematic and efficient management of household power consumption, the power consumption characteristics of controllable equipment and the energy storage characteristics of electric vehicles are modeled respectively, and the scheduling optimization objective function of household equipment under time of use price is established, and the improved particle swarm optimization algorithm is used to solve the problem. Through the example simulation, the residential power dispatching under various scenarios is analyzed. The experimental results show that the …


Two-Point Joint Cpa Attacks Against Aes And Its Simulation, Tong Yu, Jingwen Cai Aug 2021

Two-Point Joint Cpa Attacks Against Aes And Its Simulation, Tong Yu, Jingwen Cai

Journal of System Simulation

Abstract: Aiming at the problems of large sampling amount and low utilization rate of attack information in single-point power analysis attack, a method of two-point joint power analysis attack for AES (Advanced Encryption Standard) is proposed. This method selects two power leakage points for power analysis according to the correlation between the power leakage points and the key in the AES. By constructing a power leakage model of intermediate variables, an intermediate value joint function is established which means, the method can be used to recover the key of AES. The simulation results demonstrate that the attack time of …


Passenger Flow Sensitivity Analysis Of Evacuation Time For Standard Subway Station, Guoao Zhang, Ma Si, Wang Lin Aug 2021

Passenger Flow Sensitivity Analysis Of Evacuation Time For Standard Subway Station, Guoao Zhang, Ma Si, Wang Lin

Journal of System Simulation

Abstract: Underground two-level island platform stations widely existed in urban rail transit system. In order to analyze the relationship between the evacuation time and the character of passenger flow, the capacity of main evacuation facilities and the evacuation bottleneck of stations are studied, and groups of sensitivity analysis experiment are designed. The variability of the evacuation process is analyzed by comparing the output of each simulation model in a group and between groups. The simulation result shows that the station evacuation time increases within a certain limit at peak hour. And the station evacuation time is mainly affected by the …


Language And Communication In Social Networks Of Information Society, Ravshan Xudoyberganov Aug 2021

Language And Communication In Social Networks Of Information Society, Ravshan Xudoyberganov

The Light of Islam

This article analyzes the socio-philosophical and methodological aspects of the problems and prospects of language and communication in an information society. The paper notes that the communicative process is the process of formation and development of all social spheres. Language and communication provide communication between people. We know that language is of great importance as a means of communication. Language and means of communication give us a dialogic or interactive form of communication. In an information society, language and communication are a unique form of cultural, historically conditioned spiritual communication between people. The means of communication, in turn, depend on …


Flow Characterization In Mine Ventilation Fan Blade Design Using Cfd, Anwar Endris Hassen Aug 2021

Flow Characterization In Mine Ventilation Fan Blade Design Using Cfd, Anwar Endris Hassen

Journal of Sustainable Mining

In axial ventilation fans, the generation of a uniform flow velocity is desirable for better efficiency. To that end, different fan blade types have been developed to achieve better flow uniformity. This article aimed to characterize the flow distribution and its uniformity in four blade designs, namely constant chord, tapered blade, skewed blade, and tapered skewed blade, using Computational Fluid Dynamics (CFD). The study employs an iterative study where key study decisions are made as the study progresses. The study began with the selection of a blade profile for the study. A comparative study between the NACA seven-digit and four-digit …


Current State Of Seagrasses In Zanzibar: Impacts Of Coastal Economic Activities And Marine Protected Areas On Seagrass Cover, Danielle Purvis, Narriman Jiddawi Aug 2021

Current State Of Seagrasses In Zanzibar: Impacts Of Coastal Economic Activities And Marine Protected Areas On Seagrass Cover, Danielle Purvis, Narriman Jiddawi

Capstone Collection

Seagrass meadows are located abundantly in Zanzibar, Tanzania and provide essential ecosystem services, such as sediment nutrient enrichment and blue carbon sequestration. However, seagrasses have been less researched or protected than other marine ecosystems. Although environmental variables affect seagrass health, evidence suggests that anthropogenic impacts are their greatest threats. The rapid expansion of seaweed farming and tourism and widespread use of harmful small-scale fishing practices in Zanzibar have contributed to the degradation and removal of seagrass meadows, disrupted coastal marine food chains, and reduced local biodiversity that seagrasses support. Public or private marine protected areas (MPAs) protect most of Zanzibar’s …


Floodplain Geomorphology And Response To Hurricanes: Lower Pee Dee Basin, South Carolina, Thomas M. Williams, Bo Song, Daniel Hitchcock, Thomas O'Halloran Aug 2021

Floodplain Geomorphology And Response To Hurricanes: Lower Pee Dee Basin, South Carolina, Thomas M. Williams, Bo Song, Daniel Hitchcock, Thomas O'Halloran

Journal of South Carolina Water Resources

Undeveloped forested wetlands in the valleys of coastal plain rivers can play a large role in storing floodwater and attenuating river flooding. In the lower Pee Dee, Little Pee Dee, and Lynches Rivers, these wetlands played a large role in mitigating downstream flooding following Hurricane Florence. Wetland forest flood mitigation was most effective for large flows in the Great Pee Dee River, where flooding on former river terraces determined the course of overbank flow and the potential storage of floodwaters. Floodwater storage and attenuation of water level were less effective if larger flows were limited to the Little Pee Dee …


Streamflow And Tidal Dynamics In The Lower Pee Dee Basin: Hurricane Impacts, Thomas M. Williams, Bo Song, Daniel Hitchcock, Thomas O'Halloran Aug 2021

Streamflow And Tidal Dynamics In The Lower Pee Dee Basin: Hurricane Impacts, Thomas M. Williams, Bo Song, Daniel Hitchcock, Thomas O'Halloran

Journal of South Carolina Water Resources

Over past years, extreme tropical storm events along the North and South Carolina coasts—and subsequent river flooding—have warranted the need for a better understanding of the hydrologic response to these events to protect life, property, businesses, and natural and cultural resources. Our focus in this study is the Pee Dee and Waccamaw River systems, which ultimately flow into Winyah Bay near Georgetown, South Carolina. River flows, coupled with the tidal nature of these freshwater systems, are complex and difficult to predict. The objective of the work is to analyze publicly available data from gauging stations along those river system as …


Understanding Stakeholders’ Knowledge, Awareness, And Perception Of Conservation Programs In South Carolina, J. Carl Ureta, Marzieh Motallebi, Lori Dickes, Lucas Clay, Joan Ureta, Robert Baldwin Aug 2021

Understanding Stakeholders’ Knowledge, Awareness, And Perception Of Conservation Programs In South Carolina, J. Carl Ureta, Marzieh Motallebi, Lori Dickes, Lucas Clay, Joan Ureta, Robert Baldwin

Journal of South Carolina Water Resources

The increasing population and economic growth of South Carolina make it attractive for landowners to convert their land to commercial and urbanized zones. However, since ecosystems are directly affected by land use, changes in these land uses directly impact the ecosystem services (ES). Therefore, efforts to conserve ecosystems are paramount and are often supported through conservation-incentive programs. One approach for conservation programs is to provide economic incentives for landowners to retain their land as forest or agricultural land. The success of these programs eventually affects the ES recipients or “end-users,” particularly the residents. Therefore, it is important to understand the …


A Multi-Reservoir Study Of The Impact Of Uncertainty In Pool Evaporation Estimates On Water-Availability Models, R. C. Phillips, Nigel Kaye, John Saylor Aug 2021

A Multi-Reservoir Study Of The Impact Of Uncertainty In Pool Evaporation Estimates On Water-Availability Models, R. C. Phillips, Nigel Kaye, John Saylor

Journal of South Carolina Water Resources

Quantifying evaporative loss from reservoirs plays a critical role in sound water-availability management plans and in reservoir management. Various methods are used to quantify reservoir evaporation; however, each method carries a degree of uncertainty that propagates to model predictions of available water within a reservoir or a reservoir network. Herein, we explore the impact of uncertainty in reservoir evaporation on model outputs of historical and future water availability throughout the five major reservoirs in the Savannah River Basin in South Carolina, USA, using four different evaporation methods. Variability in the total available water is evaluated using the United States Army …


Mapping Center Pivot Irrigation Fields In South Carolina With Google Earth Engine And The National Agricultural Imagery Program, C. Alex Pellett Aug 2021

Mapping Center Pivot Irrigation Fields In South Carolina With Google Earth Engine And The National Agricultural Imagery Program, C. Alex Pellett

Journal of South Carolina Water Resources

Aerial images taken during the growing seasons of 2009, 2011, 2013, 2015, and 2017 were visually inspected for evidence of irrigation. Center pivot irrigation was identified by the characteristic shape of the spans and the curved tracks left by the wheels. The author manually delineated a polygon over each agricultural area where signs of irrigation infrastructure were observed. The result is a map of 2,689 polygons covering 146,662 acres in South Carolina. Compared with the United States Department of Agriculture 2017 Census of Agriculture, the sampling results account for over 69% of total irrigated area and over 98% of area …


Modeling Tidal Characteristics In A Creek-Marsh Drainage System: Implications For Stormwater Management, C. E. Brown, T. J. Callahan Aug 2021

Modeling Tidal Characteristics In A Creek-Marsh Drainage System: Implications For Stormwater Management, C. E. Brown, T. J. Callahan

Journal of South Carolina Water Resources

The traditional goal of stormwater management is to reduce the threat of flooding to life and property, and so most landscapes are engineered to maximize the speed at which the unwanted water leaves the watershed. This has been effective in landscapes with some topographic gradient. This often involves the installation of drainage ditches that disperse runoff from urban areas to receiving water bodies; in coastal areas this means a tidal creek, estuary, bay, sounds, or the coastal ocean. This practice reduces flood hazards in some cases but results in unintended effects on the natural hydrology in the watershed and downstream …


Heat Flow In The Core Of Ganymede: High Pressure-Temperature Electrical Resistivity Measurements Of Solid And Liquid Ag And Fe-S Alloys, Joshua A.H. Littleton Aug 2021

Heat Flow In The Core Of Ganymede: High Pressure-Temperature Electrical Resistivity Measurements Of Solid And Liquid Ag And Fe-S Alloys, Joshua A.H. Littleton

Electronic Thesis and Dissertation Repository

Experimental investigations of materials at high pressures (P) and temperatures (T) provide insight into the properties and behaviours expected within the inaccessible interiors of planetary bodies. Using a four-wire electrical resistance technique, the electrical resistivity (ρ) of 4d transition metal (Ag) and 3d transition metal alloys (Fe-S) were measured in the solid and molten states at high P. The thermal conductivity (κ) of these materials is inversely proportional to ρ, as described by the Wiedemann-Franz Law. When applied to planetary cores, κ is an important parameter that regulates heat transport mechanisms and magnetic field production.

A hypothesis of ‘resistivity invariance’ …


Leveraging Machine Learning Techniques Towards Intelligent Networking Automation, Cesar A. Gomez Aug 2021

Leveraging Machine Learning Techniques Towards Intelligent Networking Automation, Cesar A. Gomez

Electronic Thesis and Dissertation Repository

In this thesis, we address some of the challenges that the Intelligent Networking Automation (INA) paradigm poses. Our goal is to design schemes leveraging Machine Learning (ML) techniques to cope with situations that involve hard decision-making actions. The proposed solutions are data-driven and consist of an agent that operates at network elements such as routers, switches, or network servers. The data are gathered from realistic scenarios, either actual network deployments or emulated environments. To evaluate the enhancements that the designed schemes provide, we compare our solutions to non-intelligent ones. Additionally, we assess the trade-off between the obtained improvements and the …


On \Delta^(K)-Colouring Of Powers Of Paths And Cycles, Merlin Thomas Ellumkalayil Ms, Sudev Naduvath Aug 2021

On \Delta^(K)-Colouring Of Powers Of Paths And Cycles, Merlin Thomas Ellumkalayil Ms, Sudev Naduvath

Theory and Applications of Graphs

In an improper vertex colouring of a graph, adjacent vertices are permitted to receive same colours. An edge of an improperly coloured graph is said to be a bad edge if its end vertices have the same colour. A near-proper colouring of a graph is a colouring which minimises the number of bad edges by restricting the number of colour classes that can have adjacency among their own elements. The δ (k) - colouring is a near-proper colouring of G consisting of k given colours, where 1 ≤ k ≤ χ(G) – 1, which minimises the number of bad …


Grassland Resources In Liaoning Province Of China: Problems And Management Strategies, Guijuan Du, Jiaming Zheng Aug 2021

Grassland Resources In Liaoning Province Of China: Problems And Management Strategies, Guijuan Du, Jiaming Zheng

IGC Proceedings (1993-2023)

No abstract provided.


Dividing The Ecological Environmental Area For The Northwest Dry Grassland Of China, Genzhu Chang, Xuehui Zhou, Hongshan Yang Aug 2021

Dividing The Ecological Environmental Area For The Northwest Dry Grassland Of China, Genzhu Chang, Xuehui Zhou, Hongshan Yang

IGC Proceedings (1993-2023)

No abstract provided.