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2019

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Articles 481 - 510 of 1263

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Process Simulation And Optimization On Giant Block Erection Of Longitudinal Staggered Arrangement, Wenmin Zhu, Minghua Zhu, Xiumin Fan Apr 2019

Process Simulation And Optimization On Giant Block Erection Of Longitudinal Staggered Arrangement, Wenmin Zhu, Minghua Zhu, Xiumin Fan

Journal of System Simulation

Abstract: The process of giant block erection of longitudinal staggered arrangement is complicated. If the design of process and tooling are not reasonable, the adjustment work in the construction site, which affects the shipbuilding cycle seriously, will be abundant. To solve these problems, the method of process simulation and optimization on giant block erection were researched. Simulation models were established for carrying out the process simulation, and the simulation process was detected in real time by establishing collision detection model and virtual human model. Based on the measured data of the ship hull, the automatic calculation method of raising height …


Robust Adaptive Rate Control Algorithm And Its Simulation For P2p-Tv Streaming Media Systems, Fengjie Yin, Yang Hui, Zhang Ying Apr 2019

Robust Adaptive Rate Control Algorithm And Its Simulation For P2p-Tv Streaming Media Systems, Fengjie Yin, Yang Hui, Zhang Ying

Journal of System Simulation

Abstract: A control algorithm proposed to control the upstream rate based on sliding mode control in P2P-TV streaming media node. Through the rational design of sliding mode controller, the algorithm can adaptively control the numbers of signaling threads between neighbor pairs connected simultaneously and then control the upload rate. Further, it can achieve the fair use of resources. Due to the sliding mode control has strong robust with modeling uncertainties, time varying parameter fluctuations and external disturbances, it can avoid the system congestion under network condition change. Simulation results demonstrate that it can lead to the convergence of the …


Distribution Routing Optimization Of Fresh Agricultural Products Based On Road Conditions, Wang Heng, Yaxing Xu, Zhenfeng Wang, Tianpeng Zhou, Dechun Tian Apr 2019

Distribution Routing Optimization Of Fresh Agricultural Products Based On Road Conditions, Wang Heng, Yaxing Xu, Zhenfeng Wang, Tianpeng Zhou, Dechun Tian

Journal of System Simulation

Abstract: Reasonable arrangement of distribution route of fresh agricultural product can effectively guarantee the freshness of products, improve the distribution efficiency, and reduce the distribution cost. In practical distribution, the road condition is an important factor affecting the arrangement of the distribution route. According to the different road conditions, the speed characteristic models are set up. Meanwhile, considering the perishable and vulnerable characteristics of fresh agricultural products, the function of time window penalty cost and the function of customer satisfaction are established. Based on the comprehensive consideration of factors, such as road condition, time window and fresh consumption, a multi-objective …


Simulation Of Domestic Hot Water Using Behavior Of College Students Based On Group Characteristics, Zhou Jin, Xiaoping Yin, Xu Feng Apr 2019

Simulation Of Domestic Hot Water Using Behavior Of College Students Based On Group Characteristics, Zhou Jin, Xiaoping Yin, Xu Feng

Journal of System Simulation

Abstract: The use of domestic hot water is influenced by user’s gender and living habits, so the composition and behavior characteristics of user group have great influence on the design and operation control of domestic hot water system. The classification of hot water user group of college students was made by means of statistical analysis of original data, and the parameters related to the probability distributions of hot water use behavior were obtained. The simulation of domestic hot water using by college students was conducted and compared with the data generated from original recorded data, and the results show good …


Modeling And Simulation Of Health Degradation Trend For Wind Turbine Bearing, Xinghui Dong, Xiaoshuang Ma, Youxing Cheng, Wang Shuai Apr 2019

Modeling And Simulation Of Health Degradation Trend For Wind Turbine Bearing, Xinghui Dong, Xiaoshuang Ma, Youxing Cheng, Wang Shuai

Journal of System Simulation

Abstract: By taking a wind turbine bearing as research object, the model of bearing temperature health’s degradation trend is established through using least squares surface fitting and the monitored parameters from Supervisory Control And Data Acquisition (SCADA). Bearings’ degradation trend with unsteady characteristics is decomposed by modified Ensemble Empirical Mode Decomposition(EEMD) to obtain several relatively steady components. Components are predicted respectively by time series neural network and the predicted results of all the components are added to obtain final prediction result. Comprehensive simulations and comparisons show that the proposed method can predict the health degradation trend of wind turbine bearings …


Systematic Error Analysis Based On Hardware-In-The-Loop Simulation Environment, Zhang Duo, Manguo Liu, Zhang Xiao, Pingan Liu, Yixuan He Apr 2019

Systematic Error Analysis Based On Hardware-In-The-Loop Simulation Environment, Zhang Duo, Manguo Liu, Zhang Xiao, Pingan Liu, Yixuan He

Journal of System Simulation

Abstract: Aiming at the complex and diverse components in the semi-physical simulation environment of a certain type of anti-tank missile, the errors present different types of problems, and a systematic error analysis method based on the environment is proposed. By analyzing the composition characteristics and the error characteristics of the simulation computer, flight motion simulator, target simulator and simulation dedicated interface; the delay error of the simulation computer, the mechanical installation error of the flight motion simulator, the delay error of the target simulator and the transmission error of the simulation dedicated interface are acquired. Furthermore, by comparing the local …


Design And Simulation Of Heterogeneous Magnetron Memristive Chua Circuit, Xiaohong Zhang, Lijuan Wan, Keliu Long Apr 2019

Design And Simulation Of Heterogeneous Magnetron Memristive Chua Circuit, Xiaohong Zhang, Lijuan Wan, Keliu Long

Journal of System Simulation

Abstract: A nonlinear circuit containing two heterogeneous magnetron memristors which based on the three-order classic Chua circuit is designed, its dimensionless fifth-order mathematical model is proposed. Due to the difference in the design of the characteristic equation of the two magnetron memristors, their positions form a symmetrical structure with respect to the capacitor. The existence of chaotic properties is proved by analyzing the stability of the system equilibrium point and Lyapunov exponents. The model of five-order heterogeneous memristive Chua system and two heterogeneous magnetron memristors are implemented by Multisim. Numerical calculation and experimental results show that heterogeneous magnetron memristive Chua …


Active Disturbance Rejection Sliding Mode Control For Time-Delay Systems, Suzhen Wang, Guofa Sun, Shengrong Liu Apr 2019

Active Disturbance Rejection Sliding Mode Control For Time-Delay Systems, Suzhen Wang, Guofa Sun, Shengrong Liu

Journal of System Simulation

Abstract: Aiming at the time-delay systems with uncertainty, this paper designs a third-order nonlinear feedback extended state observer (ESO) by using the coordinate transformation. The ESO can estimate both the system states and the total disturbance signal, and the nonlinear feedback has fast convergence. By the first-order approximation of the time-delay, the output feedback control problem of the time-delay system is transformed into controlling the second-order nonlinear uncertain system with unknown function. On the basis of the tracking differentiator (TD) and the designed ESO, the second-order sliding mode controller (SMC) is designed to realize the fast and accurate tracking …


Evaluation Of Green Smart Cities In China Based On Entropy Weight - Cloud Model, Chen Li, Haixia Zhang Apr 2019

Evaluation Of Green Smart Cities In China Based On Entropy Weight - Cloud Model, Chen Li, Haixia Zhang

Journal of System Simulation

Abstract: Based on the research on green smart city at home and abroad; and aiming at the shortcomings and deficiencies of traditional evaluation methods, this paper proposes an evaluation method of combining entropy and cloud model based on the cloud model which can realize the conversion of qualitative concept and quantitative value. This method synthetically considers the subjective and objective factors; carries on the correlation analysis to the index; determines the set of evaluation indicators; uses the X-conditional cloud generator in cloud model to obtain the different levels of membership matrix corresponding to each evaluation object; and carries on the …


Integrated: A Student's Guide To Systems Engineering, Hannah Smith Apr 2019

Integrated: A Student's Guide To Systems Engineering, Hannah Smith

Research Horizons Day Posters

No abstract provided.


Essays On Time Series And Machine Learning Techniques For Risk Management, Michael Kotarinos Apr 2019

Essays On Time Series And Machine Learning Techniques For Risk Management, Michael Kotarinos

USF Tampa Graduate Theses and Dissertations

The Capital Asset Pricing Model combined with the Sharpe ratio is a standard method for choosing assets for selection in a portfolio. However, this method has many structural issues and was designed for a time when high dimensional computing was in its infancy. An alternative to these methods using a mix of Multi-Level Time Series Clustering, the MACBETH algorithm and traditional time series techniques was constructed that minimized data loss and allow for customized portfolio construction for investors with different risk profiles and specialized investment needs. It was shown that these methods are adaptable to cloud computing environments and allow …


Routing And Designing Networks For Two Transportation Problems, Liu Su Apr 2019

Routing And Designing Networks For Two Transportation Problems, Liu Su

USF Tampa Graduate Theses and Dissertations

Routing and designing are essential for transportation networks. With effective routing and designing policies, transportation networks can work safely and efficiently. There are two transportation problems: hazardous materials (hazmat) transportation and warehouse logistics. This dissertation addresses the routing of networks for both problems. For hazmat transportation, the routing can be regulated via network design. Due to catastrophic consequences of potential accidents in hazmat transportation, a risk-averse approach for routing is necessary. In this dissertation, we consider spectral risk measures, for risk-averse hazmat routing. In addition, we introduce a network design problem to select a set of closed road segments for …


A Tunable Triboelectric Wideband Energy Harvester, Daniel S. Nelson, Alwathiqbellah Ibrahim, Shahrzad Towfighian Apr 2019

A Tunable Triboelectric Wideband Energy Harvester, Daniel S. Nelson, Alwathiqbellah Ibrahim, Shahrzad Towfighian

Systems Science and Industrial Engineering Faculty Scholarship

The ability to efficiently convert mechanical energy into electrical energy has become an important topic of discussion and research in the last decade. Triboelectric generators have recently been popular for vibration energy harvesting, but despite plenty of research on its material aspect, research on combining mechanical characteristics and voltage generation output has been sparse. Many energy harvesters suffer from low operating bandwidths and are usually restricted to operating at a specific frequency. We propose a tunable triboelectric energy harvester that has a large response over a wide frequency bandwidth at low frequencies. The tunability is implemented by axially pre-loading a …


Five Whys Root Cause System Effectiveness: A Two Factor Quantitative Review, Barbara A. Key Apr 2019

Five Whys Root Cause System Effectiveness: A Two Factor Quantitative Review, Barbara A. Key

Masters Theses & Specialist Projects

Several tools exist for root cause analysis (RCA). Despite this however, many practitioners are not obtaining the quality improvement desired. Those turning to literature for guidance would find most of the information resides in case studies with anecdotal outcomes. Since 5 Whys analysis has been one of the more pervasive tools in use, this study sought to add to the root cause analysis body of knowledge by investigating tool support factors. While studied in conjunction with 5 Whys, the support variables lend themselves to other root cause analysis tools as well. The purpose of the study was to utilize a …


Domain Adaption Via Feature Selection On Explicit Feature Map, Wan Yu Deng, Amaury Lendasse, Yew Soon Ong, Ivor Wai Hung Tsang, Lin Chen, Qing Hua Zheng Apr 2019

Domain Adaption Via Feature Selection On Explicit Feature Map, Wan Yu Deng, Amaury Lendasse, Yew Soon Ong, Ivor Wai Hung Tsang, Lin Chen, Qing Hua Zheng

Engineering Management and Systems Engineering Faculty Research & Creative Works

In Most Domain Adaption Approaches, All Features Are Used for Domain Adaption. However, Often, Not Every Feature is Beneficial for Domain Adaption. in Such Cases, Incorrectly Involving All Features Might Cause the Performance to Degrade. in Other Words, to Make the Model Trained on the Source Domain Work Well on the Target Domain, it is Desirable to Find Invariant Features for Domain Adaption Rather Than using All Features. However, Invariant Features Across Domains May Lie in a Higher Order Space, instead of in the Original Feature Space. Moreover, the Discriminative Ability of Some Invariant Features Such as Shared Background Information …


Segmentation Of Sidescan Sonar Imagery Using Markov Random Fields And Extreme Learning Machine, Yan Song, Bo He, Ying Zhao, Guangliang Li, Qixin Sha, Yue Shen, Tianhong Yan, Rui Nian, Amaury Lendasse Apr 2019

Segmentation Of Sidescan Sonar Imagery Using Markov Random Fields And Extreme Learning Machine, Yan Song, Bo He, Ying Zhao, Guangliang Li, Qixin Sha, Yue Shen, Tianhong Yan, Rui Nian, Amaury Lendasse

Engineering Management and Systems Engineering Faculty Research & Creative Works

As a Widely Used Segmentation Scheme, Markov Random Field (Mrf) Utilizes K-Means Clustering to Calculate the Initial Model for Sidescan Sonar Image Segmentation. However, for the Noise and Intensity Inhomogeneity Nature of the Sidescan Sonar Images, the Segmentation Results of K-Means Clustering Have Low Accuracy, Motivating Us to Use Machine Learning Methods to Initialize Mrf. Meanwhile, an Extreme Learning Machine (Elm), a Supervised Learning Algorithm Derived from the Single-Hidden-Layer Feedforward Neural Networks, Learns Faster Than Randomly Generated Hidden-Layer Parameters and is Superior to a Support Vector Machine (Svm). Therefore, in This Paper, We Proposed a Novel Method for Sidescan Sonar …


Impacts Of Freight Consolidation And Truck Sharing On Freight Mobility, Tieming Liu, Chaoyue Zhao Apr 2019

Impacts Of Freight Consolidation And Truck Sharing On Freight Mobility, Tieming Liu, Chaoyue Zhao

Data

Corresponding data set for Tran-SET Project No. 17ITSOKS02. Abstract of the final report is stated below for reference:

"The trucking industry is an important sector of the U.S. economy. However, it is quite fragmented, hindering the efficiency of cargo transportation and the ability for small carriers to identify demands to fill full truck loads. The focus of this research is to study models and algorithms in order to aid online freight marketplaces to identify efficient consolidation strategies. To accomplish this aim, a new mixed integer programming model for the pickup and delivery problem has been developed. The model is geared …


Dynamic Pricing Of Electricity And Demand Response In Smart Communities, Vignesh Subramanian Apr 2019

Dynamic Pricing Of Electricity And Demand Response In Smart Communities, Vignesh Subramanian

USF Tampa Graduate Theses and Dissertations

Grid modernization using advanced metering infrastructure (AMI) will continue to enhance timely communication among the system operator (SO), producers, and consumers. This will further empower the vision of dynamic pricing and demand side management (DSM). The phrase dynamic pricing in this dissertation refers to the practice of disclosing binding prices of electricity just ahead of consumption. As regards DSM, the focus is on collective demand response (DR) by aggregators managing consumers’ loads in smart and connected communities (households, businesses, industries and aggregation of electric vehicle batteries). However, practitioners and researchers alike have expressed the fear that dynamic pricing may cause …


A Bridge And Engine Room Staffing And Scheduling Model For Robust Mission Accomplishment In The Littoral Combat Ships, John P. Cordle Apr 2019

A Bridge And Engine Room Staffing And Scheduling Model For Robust Mission Accomplishment In The Littoral Combat Ships, John P. Cordle

EMSE Doctoral Projects

The Navy’s Littoral Combat Ships were designed to be relatively small surface vessels for operations near a littoral shore theater. These ships were envisioned to be highly automated, networked, agile, stealthy surface combatants capable of defeating anti-access and asymmetric threats in the littorals with minimum manpower. To date, however, some of these ships have experienced significant engineering and propulsion plant failures that impacted mission accomplishment and were attributable, at least in part, to under staffing and over scheduling the human component of the automation-human operational environment. The critical human components on the Littoral Combat Ship are bridge and engine room …


Fiber-Reinforced Polymer Bridge Girders For Extremely Aggressive Environments, Abdellah Emad Azeez Apr 2019

Fiber-Reinforced Polymer Bridge Girders For Extremely Aggressive Environments, Abdellah Emad Azeez

Doctoral Dissertations and Master's Theses

In 2012, the federal government estimated that $17.5 billion was spent on inspection, rehabilitation, maintenance, and replacement of the nation’s bridges. While the average lifespan of steel and reinforced concrete bridges is 50 years, certain bridges subjected to extremely aggressive marine environments may not reach this desired target. This research paper investigates using fiber-reinforced polymer (FRP) materials as primary bridge girders in medium span bridges (30 ft. to 75 ft.). The goal of this research is to identify the most efficient and cost-effective alternative for these corrosion-resistant materials and potentially extend the lifespan of these bridges up to 75 years. …


A Hierarchical Core Reference Ontology For New Technology Insertion Design In Long Life Cycle, Complex Mission Critical Systems, Kevin J. Michael Apr 2019

A Hierarchical Core Reference Ontology For New Technology Insertion Design In Long Life Cycle, Complex Mission Critical Systems, Kevin J. Michael

EMSE Doctoral Projects

Organizations, including government, commercial and others, face numerous challenges in maintaining and upgrading long life-cycle, complex, mission critical systems. Maintaining and upgrading these systems requires the insertion and integration of new technology to avoid obsolescence of hardware software, and human skills, to improve performance, to maintain and improve security, and to extend useful life. This is particularly true of information technology (IT) intensive systems. The lack of a coherent body of knowledge to organize new technology insertion theory and practice is a significant contributor to this difficulty. This research organized the existing design, technology road mapping, obsolescence, and sustainability literature …


System Architecting Approach For Designing Deep Learning Models, Ram Deepak Gottapu, Cihan H. Dagli Apr 2019

System Architecting Approach For Designing Deep Learning Models, Ram Deepak Gottapu, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Deep Learning (DL) models have proven to be very effective in solving many challenging problems, especially, those related to computer vision, text, and speech. However, the design of such models is challenging because of the vast search space and computational complexity that needs to be explored. Our goal in this paper is to reduce the human effort required to design architectures by using a system architecture development process that allows the exploration of large design space by automating certain model construction, alternative generation, and assessment. The proposed framework is generic and targeted at all deep learning architectures that can be …


Embedded Fault Class Detection Methodology For Condition-Based Machine Monitoring And Predictive Maintenance, Nagdev Amruthnath Apr 2019

Embedded Fault Class Detection Methodology For Condition-Based Machine Monitoring And Predictive Maintenance, Nagdev Amruthnath

Dissertations

Ever since the Second Industrial Revolution, manufacturing firms have continuously been working on minimizing the inefficiencies and maximizing the productivity of their system. This objective led to the creation of the Toyota Production System which follows the motto of “making [the] highest quality products at the least cost in the shortest lead time. (Ohno, 1988)” This philosophy is widely recognized and is utilized by various industries today.

Currently, we are going through the Fourth Industrial Revolution (also called, Industry 4.0) where internet technologies are utilized to additionally maximize the productivity in the production processes. Process synchronization is one of the …


Impacts Of Freight Consolidation And Truck Sharing On Freight Mobility, Tieming Liu, Chaoyue Zhao Apr 2019

Impacts Of Freight Consolidation And Truck Sharing On Freight Mobility, Tieming Liu, Chaoyue Zhao

Publications

The trucking industry is an important sector of the U.S. economy. However, it is quite fragmented, hindering the efficiency of cargo transportation and the ability for small carriers to identify demands to fill full truck loads. The focus of this research is to study models and algorithms in order to aid online freight marketplaces to identify efficient consolidation strategies. To accomplish this aim, a new mixed integer programming model for the pickup and delivery problem has been developed. The model is geared towards identifying effective freight consolidation opportunities. A branch-and-cut algorithm to solve the model was also developed. The model …


Route Planning For A Fleet Of Electric Vehicles With Waiting Times At Charging Stations, Baoxiang Li, Shashi Shekhar Jha, Hoong Chuin Lau Apr 2019

Route Planning For A Fleet Of Electric Vehicles With Waiting Times At Charging Stations, Baoxiang Li, Shashi Shekhar Jha, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Electric Vehicles (EVs) are the next wave of technology in the transportation industry. EVs are increasingly becoming common for personal transport and pushing the boundaries to become the mainstream mode of transportation. Use of such EVs in logistic fleets for delivering customer goods is not far from becoming reality. However, managing such fleet of EVs bring new challenges in terms of battery capacities and charging infrastructure for efficient route planning. Researchers have addressed such issues considering different aspects of the EVs such as linear battery charging/discharging rate, fixed travel times, etc. In this paper, we address the issue of waiting …


The Capacitated Team Orienteering Problem, Aldy Gunawan, Kien Ming Ng, Vincent F. Yu, Gordy Adiprasetyo, Hoong Chuin Lau Apr 2019

The Capacitated Team Orienteering Problem, Aldy Gunawan, Kien Ming Ng, Vincent F. Yu, Gordy Adiprasetyo, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

This paper focuses on a recent variant of the Orienteering Problem (OP), namely the Capacitated Team OP (CTOP) which arises in the logistics industry. In this problem, each node is associated with a demand that needs to be satisfied and a score that need to be collected. Given a set of homogeneous fleet of vehicles, the objective is to find a path for each vehicle in order to maximize the total collected score, without violating the capacity and time budget. We propose an Iterated Local Search (ILS) algorithm for solving the CTOP. Two strategies, either accepting a new solution as …


Development And Initial Evaluation Of A Reinforced Cue Detection Model To Assess Situation Awareness In Commercial Aircraft Cockpits, Aysen K. Taylor Apr 2019

Development And Initial Evaluation Of A Reinforced Cue Detection Model To Assess Situation Awareness In Commercial Aircraft Cockpits, Aysen K. Taylor

Engineering Management & Systems Engineering Theses & Dissertations

Commercial transport aircraft of today vary greatly from early aircraft with regards to how the aircraft are controlled and the feedback provided from the machine to the human operator. Over time, as avionics systems became more automated, pilots had less direct control over their aircraft. Much research exists in the literature about automation issues, and several major accidents over the last twenty years spurred interest about how to maintain the benefits of automation while improving the overall human-machine interaction as the pilot is considered the last line of defense.

An important reason for maintaining or even improving overall pilot situation …


An Investigation Of General Criteria For Assessing Space Flight Systems Of Diverse Mission Concept Designs, Cindy L. Daniels Apr 2019

An Investigation Of General Criteria For Assessing Space Flight Systems Of Diverse Mission Concept Designs, Cindy L. Daniels

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research is to investigate the general criteria for assessing the technical implementation risk factors of proposed space science missions at the mission concept stage. According to the National Aeronautics and Space Administration (NASA) Space Flight Program and Project Management Handbook (NASA, 2012), the mission concept review objectives are “To evaluate the feasibility of the proposed mission concept(s) and its fulfillment of the program's needs and objectives. To determine whether the maturity of the concept and associated planning are sufficient to begin Phase A” (p.33). Experts previously defined two technical risk factors, to assess aspects of the …


Quantifying Impact Of Cyber Actions On Missions Or Business Processes: A Multilayer Propagative Approach, Unal Tatar Apr 2019

Quantifying Impact Of Cyber Actions On Missions Or Business Processes: A Multilayer Propagative Approach, Unal Tatar

Engineering Management & Systems Engineering Theses & Dissertations

Ensuring the security of cyberspace is one of the most significant challenges of the modern world because of its complexity. As the cyber environment is getting more integrated with the real world, the direct impact of cybersecurity problems on actual business frequently occur. Therefore, operational and strategic decision makers in particular need to understand the cyber environment and its potential impact on business. Cyber risk has become a top agenda item for businesses all over the world and is listed as one of the most serious global risks with significant financial implications for businesses.

Risk analysis is one of the …


Optimization Of Automated Guided Vehicles (Agv) Fleet Size With Incorporation Of Battery Management, Ahmed Hamdy Apr 2019

Optimization Of Automated Guided Vehicles (Agv) Fleet Size With Incorporation Of Battery Management, Ahmed Hamdy

Engineering Management & Systems Engineering Theses & Dissertations

An important aspect in manufacturing automation is material handling. To facilitate material handling, automated transport systems are implemented and employed. The AGV (automated guided vehicle) has become widely used for internal and external transport of materials. A critical aspect in the use of AGVs is determining the number of vehicles required for the system to meet the material handling requirements.

Several models and simulations have been applied to determine the fleet size. Most of these models and simulations do not incorporate the battery usage of the vehicles and the effect it can have on the throughput and the number of …