Engineering Commons^™

Promoting Diversity In Academic Research Communities Through Multivariate Expert Recommendation, Omar Salman

Graduate Theses and Dissertations

Expert recommendation is the process of identifying individuals who have the appropriate knowledge and skills to achieve a specific task. It has been widely used in the educational environment mainly in the hiring process, paper-reviewer assignment, and assembling conference program committees. In this research, we highlight the problem of diversity and fair representation of underrepresented groups in expertise recommendation, factors that current expertise recommendation systems rarely consider. We introduce a novel way to model experts in academia by considering demographic attributes in addition to skills. We use the h-index score to quantify skills for a researcher and we identify five …

Development Of A Reference Design For Intrusion Detection Using Neural Networks For A Smart Inverter, Ammar Mohammad Khan

Graduate Theses and Dissertations

The purpose of this thesis is to develop a reference design for a base level implementation of an intrusion detection module using artificial neural networks that is deployed onto an inverter and runs on live data for cybersecurity purposes, leveraging the latest deep learning algorithms and tools. Cybersecurity in the smart grid industry focuses on maintaining optimal standards of security in the system and a key component of this is being able to detect cyberattacks. Although researchers and engineers aim to design such devices with embedded security, attacks can and do still occur. The foundation for eventually mitigating these attacks …

An Adaptive Large Neighborhood Search For The Green Mixed Fleet Vehicle Routing Problem With Realistic Energy Consumption And Partial Recharges, Vincent F. Yu, Panca Jodiawan, Aldy Gunawan

Research Collection School Of Computing and Information Systems

This study addresses a variant of the Electric Vehicle Routing Problem with Mixed Fleet, named as the Green Mixed Fleet Vehicle Routing Problem with Realistic Energy Consumption and Partial Recharges. This problem contains three important characteristics — realistic energy consumption, partial recharging policy, and carbon emissions. An adaptive Large Neighborhood Search heuristic is developed for the problem. Experimental results show that the proposed ALNS finds optimal solutions for most small-scale benchmark instances in a significantly faster computational time compared to the performance of CPLEX solver. Moreover, it obtains high quality solutions for all medium- and large-scale instances under a reasonable …

Addressing The ‘Unseens’: Digital Wellbeing In The Remote Workplace, Holtjona Galanxhi, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

The ubiquity of sophisticated devices, along with uninterrupted access to the Internet and organizational computerized systems, allows for the “anyplace” workplace to be established. Technology has the potential to deliberately or inadvertently impact psychological wellbeing. Specific psychological demands are inadvertently imposed on remote employees whose permanent online presence is required. Hence, it is important to understand factors affecting digital wellbeing and steps that can be taken to maximize the wellbeing of remote employees. This paper provides suggestions for future research on studying the digital wellbeing of (fully or partially) remote employees. A research framework is proposed to demonstrate the different …

Vibransee: Enabling Simultaneous Visible Light Communication And Sensing, Ila Nitin Gokarn, Archan Misra

Research Collection School Of Computing and Information Systems

Driven by the ubiquitous proliferation of low-cost LED luminaires, visible light communication (VLC) has been established as a high-speed communications technology based on the high-frequency modulation of an optical source. In parallel, Visible Light Sensing (VLS) has recently demonstrated how vision-based at-a-distance sensing of mechanical vibrations (e.g., of factory equipment) can be performed using high frequency optical strobing. However, to date, exemplars of VLC and VLS have been explored in isolation, without consideration of their mutual dependencies. In this work, we explore whether and how high-throughput VLC and high-coverage VLS can be simultaneously supported. We first demonstrate the existence of …

Step-Wise Deep Learning Models For Solving Routing Problems, Liang Xin, Wen Song, Zhiguang Cao, Jie Zhang

Research Collection School Of Computing and Information Systems

Routing problems are very important in intelligent transportation systems. Recently, a number of deep learning-based methods are proposed to automatically learn construction heuristics for solving routing problems. However, these methods do not completely follow Bellman's Principle of Optimality since the visited nodes during construction are still included in the following subtasks, resulting in suboptimal policies. In this article, we propose a novel step-wise scheme which explicitly removes the visited nodes in each node selection step. We apply this scheme to two representative deep models for routing problems, pointer network and transformer attention model (TAM), and significantly improve the performance of …

Quantifying Cyber Risk By Integrating Attack Graph And Impact Graph, Omer F. Keskin

Engineering Management & Systems Engineering Theses & Dissertations

Being a relatively new risk source, models to quantify cyber risks are not well developed; therefore, cyber risk management in most businesses depends on qualitative assessments. With the increase in the economic consequences of cyber incidents, the importance of quantifying cyber risks has increased. Cyber risk quantification is also needed to establish communication among decision-makers of different levels of an enterprise, from technical personnel to top management.

The goal of this research is to build a probabilistic cybersecurity risk analysis model that relates attack propagation with impact propagation through internal dependencies and allows temporal analysis.

The contributions of the developed …

Move: Mobile Observers Variants And Extensions, Ryan Florin

Computer Science Theses & Dissertations

Traffic state estimation is a fundamental task of Intelligent Transportation Systems. Recent advances in sensor technology and emerging computer and vehicular communications paradigms have brought the task of estimating traffic state parameters in real-time within reach.

This has led to the main research question of this thesis: Can a vehicle accurately estimate traffic parameters using onboard resources shared through CV technology in a lightweight manner without utilizing centralized or roadside infrastructure?

In 1954 Wardrop and Charlesworth proposed the Moving Observer method to measure traffic parameters based on an observed number of vehicle passes. We start by proposing methods for detecting …

A Digital One Degree Of Freedom Model Of An Electromagnetic Position Sensor, Michelle Elizabeth Weinmann

Mechanical & Aerospace Engineering Theses & Dissertations

The purpose of this project was to improve an existing system currently in use by NASA Langley Research Center (LaRC). The 6-inch Magnetic Suspension and Balance System (MSBS) built at MIT is operational with control in three degrees of freedom, with two additional degrees of freedom exhibiting passive stability. The means for measuring model displacement within the magnetic environment is an Electromagnetic Position Sensor (EPS), consisting of excitation coils at 20 kHz and multiple sets of pickup coils. The pickup coil voltages are proportional to model displacement in each degree of freedom. However, the EPS electronic signal processing system is …

Uncertainty-Aware Visualization In Medical Imaging - A Survey, Christina Gillmann, Dorothee Saur, Thomas Wischgoll, Gerik Scheuermann

Computer Science and Engineering Faculty Publications

Medical imaging (image acquisition, image transformation, and image visualization) is a standard tool for clinicians in order to make diagnoses, plan surgeries, or educate students. Each of these steps is affected by uncertainty, which can highly influence the decision-making process of clinicians. Visualization can help in understanding and communicating these uncertainties. In this manuscript, we aim to summarize the current state-of-the-art in uncertainty-aware visualization in medical imaging. Our report is based on the steps involved in medical imaging as well as its applications. Requirements are formulated to examine the considered approaches. In addition, this manuscript shows which approaches can be …

Data-Driven Studies On Social Networks: Privacy And Simulation, Yasanka Sameera Horawalavithana

USF Tampa Graduate Theses and Dissertations

Social media datasets are fundamental to understanding a variety of phenomena, such as epidemics, adoption of behavior, crowd management, and political uprisings. At the same time, many such datasets capturing computer-mediated social interactions are recorded nowadays by individual researchers or by organizations. However, while the need for real social graphs and the supply of such datasets are well established, the flow of data from data owners to researchers is significantly hampered by privacy risks: even when humans’ identities are removed, or data is anonymized to some extent, studies have proven repeatedly that re-identifying anonymized user identities (i.e., de-anonymization) is doable …

Deep Peak-Shaving Transformation Planning Of Thermal Power Units Based On Approximate Dynamic Programming, Weiqing Sun, Song He, Han Dong, Kunpeng Tian

Journal of System Simulation

Abstract: The generation of renewable energy has great randomness. The lack of flexibility of thermal power unit leads to the problem of peak adjustment. Three reformation schemes for thermal power units, including the thermal power unit internal transformation, configurating energy storage, and joint transformation of the two are proposed. Taking into account the additional cost of thermal powerunit in the deep peak regulation, the planning model of thermal power units depth peak-shaving transformation considering the unit combination is proposed, and the strategy iteration approximate dynamic programming algorithm to decouple the model is presented. The “curses of dimensionality” can be avoided …

Prediction Method For Health Degree Of Front Bearing Of Wind Turbine Generator And Implementation, Yin Shi, Guolian Hou, Chi Yan, Linjuan Gong, Xiaodong Hu

Journal of System Simulation

Abstract: Aiming at the deterioration trend of front bearing of doubly-fed wind turbine generator, a new combined modeling method is proposed to predict health degree of front bearing of generator. The GMM is used to identify operating conditions of wind turbines. The temperature model of front bearing based on ELM is established respectively in each sub-condition. Combining with temperature residual characteristics and time-frequency characteristics of vibration signal, the health degree of front bearing is calculated. Based on attention mechanism, the Bi-LSTM neural network is proposed to model and predict health degree of front bearing. The result shows that the …

Design Of Lvc Simulation Test Middleware For Saas, Du Nan, Yaxin Tan

Journal of System Simulation

Abstract: LVC (Live-Virtual-Constructive) technology provides a new technical means for equipment test. In view of the large number of heterogeneous simulation resource objects and complex interaction in the LVC system test, which can not meet the test task requirements of quick response of the weapon system, the middleware and application model framework is reformed according to the remote method invocation based on TENA. The functional modules of LVC simulation middleware including model running component, publishing and ordering component, message processing component and real-time running component are designed to provide efficient real-time communication mechanism for LVC simulation and support the application …

Simulation On The Development Of Residential Distributed Photovoltaic Power Generation Under The Declining Trend Of Feed-In-Tariff, Libo Zhang, Lulu Ge, Changqi Chen, Mingduan Tang

Journal of System Simulation

Abstract: Residential Distributed Photovoltaic Generation (R-DPVG) has become the important developing force of PV generation in China. As the declining of Feed-in-Tariff (FIT), system dynamics method is used to construct a causal loop model for R-DPVG’s development, and relevant factors and their feedback mechanism are qualitatively analyzed. Then a stock-flow model is build, and the ROI, installed capacity, and policy subsidy costs of R-DPVG are simulated under some combined scenarios based on declining FIT. The simulation proves R-DPVG’s FIT will be reduced to 0.05 ~ 0.1 yuan/(kW?h) in the next three years till cancelled. FIT cutting amplitude, capacity and targets …

Approximate Method Of Spares Demand Prediction For Weibull Distribution Items Based On Piecewise Function, Songshi Shao, Zhihua Zhang, Xiaojie Mo

Journal of System Simulation

Abstract: Demand prediction model for spare parts with Weibull distribution involves multiple infinite series, therefore, spares demand calculation is a difficult issue. The approximate calculation method generally used is often subject to large errors. According to the principle of renewal function, the approximated demand calculation method for spares of Weibull distribution using piecewise function to approximate the renewal function is proposed. It effectively avoids the issue of computational complexity for spares demand prediction. Theoretical analysis shows that the proposed approximated algorithm ensures the calculation result of spares demand is less than that of engineering approximation algorithm. According to the given …

Research On Description Specification Of Extensible Simulation Scenario, Xiangzhong Xu, Xiong Jun, Fengwei Shen

Journal of System Simulation

Abstract: Simulation scenario description specification is of great significance to speed the Simulation Scenario Data (SSD) preparation, to improve the quality and to promote the reuse of the SSD. An in-depth comparison between simulation scenario and military scenario is made. The composition and application process of military scenario based on the description specification are designed, above which, the design scheme of the description specification is discussed. The extensible military scenario description specification is proposed from the following two aspects, that is, the basic elements including time and coordinate system, and the data interchange format. Series of scenario instances are produced. …

Research On Chemical Simulation Environment Modeling Based On Complex Terrain, Shunhua Liu, Fang Min

Journal of System Simulation

Abstract: Environment simulation is an important part of the construction of simulation training system. Without considering terrain factors in current chemical simulation environment, there are many problems in directing and controlling, simulation interacting, estimating and evaluating of simulation training. Based on the classical Gaussian diffusion model, the new model is suitable for the complex terrain chemical simulation environment through terrain elevation correction, diffusion parameter correction and mass conservation correction. The simulated chemical hazard area is in line with the atmospheric diffusion law of complex terrain. The model presents a realistic environment and fast computing ability, which solves the problem of …

Pathfinder Algorithm For Green Pipeline Scheduling With Limited Buffers, Hu Rong, Yuming Dong, Bin Qian

Journal of System Simulation

Abstract: A Hybrid Pathfinder Algorithm (HPFA) is proposed for solving the green flow shop scheduling problem with limited buffers and energy threshold constraints (GFSSP_LBET). The optimization criteria are to minimize the total energy consumption and the makespan. In order to enhance the global search ability of HPFA, a distance-based selection scheme is designed to determine each pathfinder's followers to ensure that the near regions of any pathfinder can get a certain search. A self-learning search strategy integrating multiple operations is designed to perform multi-neighborhood search on the updated pathfinders, which can improve the local exploitation ability of HPFA. Simulation experiments …

Yard Layout Optimization For General Cargo Terminal, Zhixiong Liu, Dong Yu, Chunjun Zhang

Journal of System Simulation

Abstract: Yard layout is an important component of the port yard allocation decision which affects the cargo storage capacity and through capacity for the port yard. As to the general cargo yard, combined with the cargo type and the yard storage strategy, the yard layout optimization model for the general cargo terminal is presented based on the statistical analysis for the production data when the optimization aim is minimizing the total horizontal transport distance of the trailer. The yard layout optimization results are employed by the mathematical tool Gurobi for different storage strategies, and the yard layout optimization results are …

Research On Time Performance Simulation And Analysis Technology Of Aviation Complex Embedded System, Lingsha Zheng, Jiang Bing, Zhe Zhao, Zhaoxu Yang

Journal of System Simulation

Abstract: As a core member of an embedded system, the embedded computer's time performance plays a key role in the comprehensive performance of the system's functional performance. However, as the complexity of aviation products continues to increase, traditional system development methods are facing the challenge for verification. In order to improve the accuracy of time performance analysis for the complex embedded system, find the potential hazards in the design of scheduling early, and avoid the system comprehensive stage design iteration caused by the time system defects, the methodology of the construction of the model and the analysis method of the …

Research On Component-Based Modeling Of Simulation Entity For Logistics And Equipment Support, Cao Qi, Qun Xiang, Wenzheng Wang

Journal of System Simulation

Abstract: There has been a lack of efficient and advanced simulation training means and systems for logistics and equipment support. Aiming at the characteristics of non-antagonism, uncertainty, timeliness, parallelism and discontinuity in the simulation of support operation, the abstraction of three entities, three interaction relations and three organization relations is put forward. By using component-based modeling, the entity for logistics and equipment support is further decomposed into several attribute components and behavior components for modeling, which effectively solves the problem of entity modeling in simulation training of support operation. In this way, the conceptual modeling tool, simulation model …

Research On The Overall Design And Key Technology Of “Human In The Loop” Synthetic Training Simulation, Zhiming Dong, Guangchao Zhu, Xiangzhong Xu, Yaxin Tan, Fan Rui

Journal of System Simulation

Abstract: Aiming at the difficulties of "human-in-the-loop" synthetic training simulation such as large scale, many entities, decentralized deployment and many heterogeneous systems. After study the construction of US Army synthetic training environment, a sustainable evolution cloud service architecture of distributed synthetic training simulation based on TISA middleware is designed, and a composable multi-level synthetic training simulation application model is put forward. It solves the technical problems of distributed training simulation, which are real-time interconnection and interoperability, consistency of battlefield environment, model composition and reuse, simulation as a service, etc. It provides technical supports for large-scale "human-in-the-loop" tactical confrontation exercises and …

Dynamic Control Of Twin-Workshop Model Of Circuit Breaker Considering Takt Time Constraints, Shu Liang, Zhang Jie, Yanfang Yang, Yang Miao, Ziran Wu

Journal of System Simulation

Abstract: The production takt time greatly impact on the twin system modeling of assembly line. A dynamic control method of the twin workshop model is proposed, which considers the takt time constraints is proposed. Detecting the motion of the circuit breaker unit and the assembly line system, and the dynamic motion model of the circuit breaker twins are developed based on the takt time calculation. Through driving force loading, motion logic script controlling and switching, the twin mapping of the assembly line system is realized with fixed and flexible takt time as well. The circuit breaker’s directional bounding boxes and …

Research On Intrusion Detection Based On Stacked Autoencoder And Long-Short Memory, Lin Shuo, An Lei, Zhijun Gao, Shan Dan, Wenli Shang

Journal of System Simulation

Abstract: As network attacks increasingly hidden, intelligent and complex. Simple machine learning cannot deal with attacks timely. A deep learning method based on the combination of SDAE and LSTM is proposed. Firstly, the distribution rules of network data are extracted intelligently layer by layer by SDAE, and the diverse anomaly features of high-dimensional data ate extracted by using coefficient penalty and reconstruction error of each coding layer. Then, LSTM’ s memory function and the powerful learning ability of sequence data are used to classify learning depth. Finally, the experiments are carried out with the UNSW-NB15 data set, which is analyzed …

Creating Synthetic Satellite Cloud Data Based On Gan Method, Wencong Cheng, Xiaokang Shi, Zhigang Wang

Journal of System Simulation

Abstract: To create the synthetic satellite cloud data in the domain of Meteorology, a method based on Generative Adversarial Networks (GAN) is proposed. Depending on ability of the nonlinear mapping and the information extraction of raster data with the deep learning network, a deep generative adversarial network model is proposed to extract the corresponding information between the numerical weather prediction(NWP) products and the satellite cloud data, and then the appropriate elements of the NWP product are chosen as the input to synthesize the corresponding satellite cloud data. The experiments are conducted on the re-analysis products of the European Centre …

Research Of Super-Resolution Processing Of Invoice Image Based On Generative Adversarial Network, Xinli Li, Changming Zou, Guotian Yang, Liu He

Journal of System Simulation

Abstract: Automatic identification of invoices can effectively improve financial efficiency. But low-resolution invoice image reduces the accuracy of automatic identification, an ESRGAN (Encoder Super-resolution Generative Adversarial Network) network for super-resolution processing of invoice images is proposed. The ESRGAN network is based on a conditional generative adversarial network. An auxiliary encoder is designed to guide the network to generate a more realistic super-resolution image. Based on the actual invoice image, the ESRGAN network and the conventional image processing, SRCNN (Super-resolution Convolutional Neural Networks) network and SRGAN (Super-resolution Generative Adversarial Network) network. The model is evaluated through two evaluation indicators of peak …

Trajectory Tracking Control Of Robotic Manipulators Based On Smooth Second-Order Sliding Mode, Ruimin Zhang, Qiaoyu Chen

Journal of System Simulation

Abstract: The robotic manipulators have characteristics of strong nonlinearity, strong coupling, multiple input and output, uncertainties, and so on. It is necessary to proposed a multivariable smooth second-order sliding mode trajectory tracking control method. The method can eliminate the chattering in the conventional sliding mode control and increase convergence speed. The property of finite time convergency is proved by the Lyapunov stability theory. Furthermore, the method is applied for the tracking control of two-joint robotic manipulators with model uncertainty and external disturbances. The simulation results show that the proposed method is effective and has high control precision and strong robustness.

Research On Digital Protection System Of Intangible Cultural Heritage Based On Mobile Augmented Reality Technology, Shouming Hou, Ge Qian, Yanyan Liu

Journal of System Simulation

Abstract: Aiming at the problem of the single form and poor interaction of intangible cultural heritage protection, a non-heritage digital online display system is designed and implemented based on mobile augmented reality technology. Taking clay sculpture non-heritage protection as an example, the main functional modules of the system cloud and mobile terminal are designed. Based on a combination of 3D scanning and iterative mesh simplification, a fast modeling method is proposed. ORB-FV and optical flow tracking algorithm are used for online recognition and tracking registration of images. The system is developed based on Unity3D. The test results show that, …

Fault Diagnosis Of Mechanical Equipment Based On Ga-Svr With Missing Data In Small Samples, Jingjing Wei, Qinming Liu, Chunming Ye, Guanlin Li

Journal of System Simulation

Abstract: In view of the equipment fault diagnosis with small and missing sample data, a method of missing data filling based on support vector regression optimized by genetic algorithm is proposed to improve the accuracy of equipment fault diagnosis. The support vector regression optimized by genetic algorithm was trained by other data values of missing data, and univariate prediction results were obtained. The training set was reconstructed through correlation analysis, so as to obtain the multivariate prediction results. Dynamic weights were established to combine univariate prediction results and multivariate prediction results to fill in the missing data. The …