Engineering Commons^™

Simulation Evaluation For Service Facilities Distribution And Flow Lines Optimization On Urban Rail Transfer Station, Liu Feng, Chunfu Shao, Hongfei Jia, Chunjiao Dong

Journal of System Simulation

Abstract: The rationality of passenger flow lines design and service facilities distribution inside urban rail transfer station directly affects the passenger's transfer efficiency. The Simulation technology are used to evaluate the station's transfer efficiency, and the optimal plan can be proposed, which can not only avoid the crowded passenger flow, but also improve the efficiency. The features of peak passenger flow are considered, the service level of the passenger's stay time is given, the change of congested area's passenger flow density is expressed in the form of time-varying chart. Combined with the overall chart of the average passenger flow density, …

Reduced-Order Modeling Of Loosening In Bolted Joints And Dynamic Interactions Between Axially Aligned Threaded Joints, Sandro Aldana

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

Maintaining effective preload in bolted joints is critical for ensuring long-term performance and safety throughout the operation of any assembled structure. The loosening of bolted joints has been studied since the Industrial Revolution, but modeling approaches have only emerged over the past three decades. Although existing approaches are capable of simulating or predicting loosening in a single joint consisting of a single bolt, they are too computationally expensive to be used to model loosening in large structures consisting of many bolts. The objective of this thesis is to construct and employ a reduced-order modeling (ROM) approach that treats the internal …

Research On A Dynamically Perceptive Connectivity Restoration Method, Hua Xiang, Baohua Li, Hongjuan Yao, Wang Zhao, Jiaxian Zuo

Journal of System Simulation

Abstract: The cluster communication network has the characteristics of time-varying topology, strong node mobility, and unstable link status, etc. It is difficult to maintain a stable topology. The network is divided into disconnected subgroups. In order to solve the communication problem between different groups, the cooperative relay node is introduced and a dynamic-sensing connection recovery method is proposed. A cooperative communication model is built and the mathematical expression of link quality indicators is deduced, which designs a multi-objective link evaluation function and achieves the optimal relay location planning through a multi-objective connectivity recovery algorithm. Simulation results show that the …

Research On Generating Technology For Equipment Standard Set Based On Uaf Modeling, Shuofang Zheng, Ruiheng He, Wenming Ren

Journal of System Simulation

Abstract: In order to meet the requirements of equipment standardization work of top-down design of current era, the modeling principles and methods of Unified Architecture Frame (UAF) are studied. Focus on the construction of four standard view models specified by UAF, Standards taxonomy, Standards structure, Standards roadmap, Standards traceability, the correlation model of operation perspective, requirement perspective and resource perspective are analyzed to form the requirement-driven equipment standard set generation technology. A new standard generation mechanism oriented to use scenarios and closely related to equipment development needs is established, and a new entry point for equipment standardization is proposed. The …

Research On Active Suspension Control Of High-Speed Train Based On Fuzzy Compound Strategy, Jianjun Meng, Zhongjun Wang, Ruxun Xu, Decang Li

Journal of System Simulation

Abstract: In order to improve the running stability of high-speed train, a semi-vertical six-degree-of- freedom state space model is established based on the active suspension system. Based on fuzzy control theory, the fuzzy controllers and fuzzy PID controllers are designed. Aiming at the defects of strong subjectivity of fuzzy PID control which needs manual adjustment, particle swarm optimization is used to optimize the initial parameters of the controller to make the suspension system be more correspond with the objective reality. In order to verify the advance of this strategy, with the sky-hook damping strategy for comparison, the controller model …

Simulation And Optimization Of Supersonic Drag Characteristics Of Blunt Cone Ascender, Xiazhen Liu, Yuan Wu, Li Qi, Zhao Rui, Zhang Jian, Zhonghua Lu

Journal of System Simulation

Abstract: Reducing shock drag is an important objective of the aerodynamic optimization of Mars ascenders. The CFD(Computational Fluid Dynamics) method is used to study the supersonic drag characteristics of a typical blunt cone ascender. Under the design constraints of slenderness ratio of 0.42, 13 groups busbar shape set of zero-lift drag are compared, and the longitudinal static and dynamic stability are discussed. The research results show that, under the design constraints, the blunt shape with large bulbous and a gently sloped conical surface has low drag characteristics. The reason is that, after passing through the bulbous, the supersonic airflow …

Uniform Experimental Design Of Constrained Region Based On Evolutionary Algorithm, Jianing Wei, Hao Hao, Qutong Chang, Lin Tao, Zhang Hu

Journal of System Simulation

Abstract: The parameters of a simulation system are usually generated by the experimental design. Aiming at high design difficulty and computational cost of the uniform experimental design, of the constraint region, a two-stage differential evolutionary algorithm is further improved. The design is modeled as a constrained optimization problem. A strategy combining distribution estimation algorithm (EDA) and differential evolution (DE) is adopted. A point-deletion method is proposed to reduce the time complexity of optimizing the population uniformity. To demonstrate the advantages, the test instances and engineering applications are used in experimental analysis. The experimental results show that the performance, stability, and …

Research On Agile Reentry Method For Maneuvering Vehicle, Lin Yue, Yingmin Jia, Songtao Fan

Journal of System Simulation

Abstract: Alarge-scale orbit maneuver method is proposed and analyzed for hypersonic space reentry vehicles, and the air assisted methods are adopted to conduct space orbit maneuvers by complying with the energy balance strategy of the aircraft. By the L/D ratio of aircraft, the efficiency of the propellant use during orbital maneuvers is elevated, and the maneuverability is also enhanced, while the risk of aircraft being tracked in space can be reduced. Aero-assisted guidance technology is applied based on full-coefficient adaptive prediction-correction technology which significantly simplifies the computation of the GNC computer, while such application ensures the convergence and enhances the …

Transmission Process Prediction Of Novel Coronavirus Based On System Dynamics, Xuepeng Lu, Shang Jiao, Junhui Zhao, Lulu Lü, Zhou Li

Journal of System Simulation

Abstract: The transmission characteristics of novel coronavirus is considered and a new SE4IR2 model based on the principle of system dynamics is proposed. The US epidemic data from June to November is used to set the isolation rate and other parameters, and the SE4IR2 model is used to fit, analyze and predict the development of the epidemic trend in the next stage. The empirical part uses the data from June to November in the United States to achieve the parameters of the SE4IR2 model, obtains the parameter values in December and January through the time series prediction model, and compares …

Optimization Of Urban Metro-Based Underground Logistics System Network With Hub-And-Spoke Layout, Ren Rui, Wanjie Hu, Jianjun Dong, Zhilong Chen

Journal of System Simulation

Abstract: Dual application of passenger commuting and underground logistics based on urban metro (M-ULS) provides a solution for traffic congestion. A three-stage optimization approach for the hub-and-spoke M-ULS network is proposed. An Entropy-TOPSIS model for underground flow screening was established based on indicators of freight flows unity, order priority and regional accessibility, considering facility capacity constraints, a location-allocation-routing combinatorial model with construction and operation costs objectives is proposed, Set Coverage Exact Algorithm, Adaptive Immunity Clone Selection Algorithm and Floyd-Warshall Algorithm are developed. Geographic information statistics of Nanjing is applied as the benchmark for real-world simulation. Results show that the modeling …

Research On Simulation Experiment Support Technology For Complex Sos Of Live And Constructive Symbiosis, Wu Xi, Ma Jun

Journal of System Simulation

Abstract: The technology of simulation experiment for System of Systems (SoS) is very important in research of complex SoS. The operation SoS is typical complex SoS.Based on the concept of parallel system, symbiotic simulation, digital twin, etc., the main characteristics of the technology are summarized. Focus on the architecture of complex system simulation experiment environment, the experiment environment architecture, hybrid simulation driving mechanism and virtual real data access mode are studied. A feasible method is provided to carry out the complex SoS experiment of multi domain joint, data fusion, resource integration and human-computer integration, and the comprehensive application of …

Research On Control Strategy Of Isolated Ac-Dc Matrix Converter Under Input Unbalance, Wenlang Deng, Li Yong, Hongbin Pan

Journal of System Simulation

Abstract: To reduce the active power fluctuation of the isolated AC-DC matrix converter (IAMC) under the input unbalance and to suppress the resonance of the LC filter, a deadbeat direct power control strategy based on active damping is proposed. The strategy uses the grid-side current and its delay component to calculate the IAMC input side filter capacitor voltage, which eliminates the high-precision voltage sensor of traditional active damping control, reduces the hardware cost, without the rotation coordinate transformation and phase-locked loops, so the calculation cost is small. The simulation results show that the proposed control strategy can effectively …

Final 2021 Residential Metals Abatement Program (Rmap) School Soil Sampling Field Sampling Plan (Fsp) Submittal #4 [Covering Butte Central Elementary & Middle School, Butte Central High School, Butte High School/Annex, East Middle School, Jeremy Bullock Soccer Fields, Webster Garfield School, & Whittier Elementary], Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Final 2021 Residential Metals Abatement Program (Rmap) School Soil Sampling Field Sampling Plan (Fsp) Submittal #3 [Covering Emerson Elementary, Headstart (Former Lincoln School), Headstart (Former Monroe School), & Margaret Leary Elementary], Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

An Analysis Of Capillary Flow In Finite Length Interior Corners, Samuel Shaw Mohler

Dissertations and Theses

We analyze the mathematical robustness of slow massively parallel interior corner flows in low gravity environments. An interior corner provides a preferential orientation in low gravity environments. This is a luxury usually only found on earth. It also provides a passive pumping mechanism due to geometry of a conduit. The driving force for this flow is a pressure difference due to local surface curvature gradients. An alternative reasoning is that due to the geometrical constraints the interior corner surface energy is unbounded below. This results in the liquid wicking into corners indefinitely. Interior corner flow's main quantity of interest is …

Finite Element Numerical Modeling And Parametric Study Of Geosynthetic Reinforced Pile-Supported Embankments, Abdallah Ikbarieh

LSU Master's Theses

This study directed at investigating the performance of the pile-supported embankment system utilizing a geosynthetic reinforced load transfer platform (GRLTP) using Finite Element numerical modeling. A 2D Finite Element Modeling (FEM) methodology was first developed using PLAXIS 2D 2021 computer software and verified by well-documented case studies in the literature of this system. Second, a performance prediction was made for a field case study of the Amite River Project near French Settlement, which is located along Route LA 16 Livingston Parish in Louisiana State. A comprehensive FEM parametric study was then carried out to evaluate the performance of the system …

Optimization Of Mechanical Properties At The Infarct Border Zone, Kaushik Sunder

LSU Master's Theses

A myocardial infarction (MI) occurs every 39 seconds in the United States. As of 2016, an estimated 550,000 new and 200,000 recurrent episodes of myocardial infarction (MI) occur each year in the United States was. Infarction is often distinguished by a considerable decrease in wall thickness and an increase in heart size or left ventricular volume. This behavior happens when there is a prolonged lack of blood flow, usually due to damage or clotting, which causes cardiomyocytes to die (CMs). The development of non-contractile infarct scarring is the primary pathophysiology of MI. While the infarct scar prevents myocardial rupture during …

An Efficient Multi-Message And Multi-Receiver Signcryption Scheme For Heterogeneous Smart Mobile Iot, Jianying Qiu, Kai Fan, Kuan Zhang, Qiang Pan, Hui Li, Yintang Yang

Department of Electrical and Computer Engineering: Faculty Publications

The Internet of Things (IoT) is developing towards smart and mobile Internet of Things (SM-IoT), which has made great progress. Due to the inherent heterogeneity, distribution, intensive communication, and resource constraints of SM-IoT, efficient security and privacy communication protocols become a particularly critical challenge. Signcryption has received considerable attention. Various signcryption schemes have been proposed to solve secure communication. However, most of them are low in efficiency, without the consideration of characteristics of the SM-IoT. In this paper, we propose a signcryption scheme to achieve efficient secure multi-message and multi-receiver communication for the heterogeneous and distributed SM-IoT. We develop Identity-based …

Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead

PRC-Affiliated Research

Aquatic therapy for rehabilitation can be performed in a variety of environments, which can vary from a traditional swimming pool to a self-contained underwater treadmill. While kinematic analysis has been performed in large volume swimming pools using specific underwater motion capture systems, researchers may only have access to a land-based motion-capture system, which is not waterproof. Additionally, underwater motion capture systems may not fit within the confines of a smaller underwater treadmill. Thus, the purpose of this study was to design and analyze methodology to quantify lower limb kinematics during an aquatic treadmill session, using a land-based motion capture system. …

Kinematic Analysis Of Gait In An Underwater Treadmill Using Land-Based Vicon T 40s Motion Capture Cameras Arranged Externally, Shreyas L. Raghu, Ryan T. Conners, Chang-Kwon Kang, David B. Landrum, Paul N. Whitehead

PRC-Affiliated Research

Aquatic therapy for rehabilitation can be performed in a variety of environments, which can vary from a traditional swimming pool to a self-contained underwater treadmill. While kinematic analysis has been performed in large volume swimming pools using specific underwater motion capture systems, researchers may only have access to a land-based motion-capture system, which is not waterproof. Additionally, underwater motion capture systems may not fit within the confines of a smaller underwater treadmill. Thus, the purpose of this study was to design and analyze methodology to quantify lower limb kinematics during an aquatic treadmill session, using a land-based motion capture system. …

Kinematic Demands On Pile-Supported Wharves Due To Liquefaction-Induced Lateral Ground Deformations, Thomas John Torkelson Ii

Dissertations and Theses

Kinematic demands from lateral soil deformations can be a major cause of damage to maritime and highway transportation structures such as wharves, ports, and bridges. Data from five centrifuge tests on pile-supported wharves were used to evaluate the accuracy of Newmark Sliding Block Analysis in estimating the kinematic demands on piles. The piles in the centrifuge tests were subjected to varying degrees of liquefaction-induced lateral ground deformations. Pile-pinning effects were included in the analysis by incorporating the lateral pile resistance in the limit-equilibrium slope stability analysis. The results of the analysis have shown that the median Newmark displacements better estimated …

An Improved Earned Value Management Method Integrating Quality And Safety, Brian Briggs

LSU Doctoral Dissertations

The construction industry invests significant time and money to improve quality and safety while reducing cost and schedule impacts. The industry has a sincere desire to improve construction project management methods to improve efficiency. Historically, quality and safety underperformances result from undermanaged quality control and safety activities. The cost and schedule impacts associated with poor quality work have always had an impact on construction operations. The unprecedented challenges and uncertainties of COVID-19 highlighted the need to improve the Earned Value Management (EVM) method within construction to reflect these quality and safety activities. The central goal of this dissertation is to …

Incorporating A Mid-Semester Project To Evaluate Communication, And Leadership Skills For Undergraduate Engineering Students In The Statics/Strength Of Materials Course: A Comparative Assessment Before And During Covid-19, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications

In this research study, a Popsicle-bridge project was assigned to a cohort of undergraduate engineering students enrolled in a Statics and Strength of Materials Course to enhance technical, communication, and leadership skills when working in a group setting. In most undergraduate engineering courses, the technical content is primarily emphasized for the academic development of the student. However, a practicing engineer must be able to possess and apply communication and leadership skills, which are often excluded from the existing curriculum. The first assessment of this project was completed with a cohort of 85 students in the Fall of 2019 before the …

Compliance With Hand Sanitizer Quality During The Sars-Cov-2 Pandemic: Assessing The Impurities In An Ethanol Plant, Gabriel Cohen, Nathan Kreutzer, Katie M. Mowat, Ashraf Aly Hassan, Bruce I. Dvorak

Department of Civil and Environmental Engineering: Faculty Publications

Using alcohol-based disinfectants is an effective method for preventing the spread of COVID-19. However, non-traditional manufacturers of alcohol-based disinfectants, such as ethanol plants, need to undergo additional treatment to curb their impurities to limits set by the Food and Drug Association (FDA) to produce alcohol-based disinfectants. To transform them to disinfectant-grade alcohol, 17 process streams in a dry-mill ethanol plant were analyzed to determine the quality parameters for acetaldehyde, acetal, propanol, methanol, and water, including chemical oxygen demand, total suspended solids, and nutrients. Results suggest that the process stream generated by the distillation column requires further treatment because the acetaldehyde …

Hydrochloric Acid Modification And Lead Removal Studies On Naturally Occurring Zeolites From Nevada, New Mexico, And Arizona, Garven M. Huntley, Rudy Luck, Michael Mullins, Nick Newberry

Michigan Tech Publications, Part 1

Four naturally occurring zeolites were examined to verify their assignments as chabazites AZLB-Ca and AZLB-Na (Bowie, Arizona) and clinoptilolites NM-Ca (Winston, New Mexico) and NV-Na (Ash Meadows, Nevada). Based on powder X-ray diffraction, NM-Ca was discovered to be mostly quartz with some clinoptilolite residues. Treatment with concentrated HCl (12.1 M) acid resulted in AZLB-Ca and AZLB-Na, the chabazite-like species, becoming amorphous, as confirmed by powder X-ray diffraction. In contrast, NM-Ca and NV-Na, which are clinoptilolite-like species, withstood boiling in concentrated HCl acid. This treatment removes calcium, magnesium, sodium, potassium, aluminum, and iron atoms or ions from the framework while leaving …

Assessment Of Long-Term Performance Of Pavements Containing Warm Mix Asphalt Technologies In Louisiana, Kwadwo Ampadu Boateng

LSU Master's Theses

This study focused on the assessment of long-term performance of asphalt pavements containing warm mix asphalt technologies in Louisiana. A total of five rehabilitation projects were studied in the state of Louisiana. The study consisted of engineering desk analyses of field performance indicators, indices and the initial laboratory performance indicators measured for five rehabilitation projects.

The engineering desk study consisted of a review of literature from previous WMA technology projects done in Louisiana. Additionally, data was acquired and validated from the Louisiana Pavement Management System (PMS). Pavement performance indicators (i.e., cracking (transverse, longitudinal, and fatigue cracking), roughness, rutting, and pavement …

Th2/Th1 Cytokine Imbalance Is Associated With Higher Covid-19 Risk Mortality, Ana B. Pavel, Jacob W. Glickman, James R. Michels, Seunghee Kim-Schulze, Rachel L. Miller, Emma Guttman-Yassky

Faculty and Student Publications

A major component of COVID-19 severe respiratory syndrome is the patient’s immune response to the SARS-CoV-2 virus and the consequential multi-organ inflammatory response. Several studies suggested a potential role of CD4+ T cells in COVID-19 severe respiratory syndrome. We first hypothesized that there is a type 2 helper (Th2)/type 1 helper (Th1) imbalance in older age, male, asthma, smokers, and high ACE2 expression phenotype in the airway of non-infected patients. Next, we hypothesized that a Th2/Th1 imbalance may predict higher mortality in COVID-19 infected hospitalized patients with and without patient reported current asthma. We first analyzed publicly available gene expression …

Epoxy Curing: Paramount Or Trivial? A Cure Path Dependent Inquiry, Jared Bates

Dissertations

The presented research delves into epoxy network formation corroborating reactant concentration profiles and physical property development throughout cure, providing an experimental basis for burgeoning molecular dynamics and coarse-grained simulation methodologies. Herein, three primary subjects were investigated: the first two examine neat and toughened epoxide/amine network formation with respect to various cure profiles aimed at altering reaction pathways, the final chapter intends to augment traditionally utilized activation energy (E_a) methodologies.

Neat and toughened epoxide/amine slurries were monitored in-situ throughout cure via near infrared (NIR) spectroscopy and rheological techniques. Functional group conversion and moduli development were related with specific attention …

Quo Vadis Lakes Azuei And Enriquillo: A Future Outlook For Two Of The Caribbean Basin's Largest Lakes, Mahrokh Moknatian, Michael Piasecki

Publications and Research

Lakes Azuei (LA) and Enriquillo (LE) on Hispaniola Island started expanding in 2005 and continued to do so until 2016. After inundating large swaths of arable land, submerging a small community, and threatening to swallow a significant trade route between the Dominican Republic and Haiti; worries persisted at how far this seemingly unstoppable expansion would go. The paper outlines the approach to a look forward to answer this question vis-à-vis climate change scenarios developed by the Intergovernmental Panel on Climate Change (IPCC). It uses numerical representations of the two lakes, and it examines how the lakes might evolve, deploying three …

On Communication For Distributed Babai Point Computation, Maiara F. Bollauf, Vinay A. Vaishampayan, Sueli I.R. Costa

Publications and Research

We present a communication-efficient distributed protocol for computing the Babai point, an approximate nearest point for a random vector X∈Rn in a given lattice. We show that the protocol is optimal in the sense that it minimizes the sum rate when the components of X are mutually independent. We then investigate the error probability, i.e. the probability that the Babai point does not coincide with the nearest lattice point, motivated by the fact that for some cases, a distributed algorithm for finding the Babai point is sufficient for finding the nearest lattice point itself. Two different probability models for X …