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2023

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Full-Text Articles in Engineering

Development Opportunities And Technical Challenges Of Industrialization For Hydrogen Production From Bio-Ethanol Reforming, Xue Han, Hong He, Guojun Yue, Hailong Lin, Jinsong Liu, Bin Yu Jan 2023

Development Opportunities And Technical Challenges Of Industrialization For Hydrogen Production From Bio-Ethanol Reforming, Xue Han, Hong He, Guojun Yue, Hailong Lin, Jinsong Liu, Bin Yu

Bulletin of Chinese Academy of Sciences (Chinese Version)

Bio-ethanol reforming for hydrogen production, using renewable raw materials and adopting mature and efficient chemical processes, is an important source of green hydrogen supply to achieve the goals of carbon peaking and carbon neutrality. Bio-ethanol is a widely used substitute for fossil fuels. With the continuous progress of cellulosic ethanol technology in recent years, bio-ethanol will gradually break through the constraints of starch-based raw material supply. Based on the industrialization achievements of hydrogen production and bio-ethanol, bio-ethanol reforming can realize a rapid linkage with the existing hydrogen energy industry. However, the existence of a carbon-carbon signal bond in ethanol poses …


Air Carrier Pilot Training, Supply & Recruitment Challenges, Paul Ryder, Todd Lisak Jan 2023

Air Carrier Pilot Training, Supply & Recruitment Challenges, Paul Ryder, Todd Lisak

National Training Aircraft Symposium (NTAS)

The route to airline recovery following the global COVID-19 pandemic is flush with opportunity for airlines, unions, and regulators to work together within current regulatory structures to recruit the next generation of aviation professionals, while continuing to ensure they are properly trained, qualified and mentored for safe flight operations. As an industry we have raised interest in pursuing aviation, but more still should be done.

The pace of the recovery from the pandemic induced reductions in air travel is testing United States pilot training and recruitment systems.

The reductions in air travel at the beginning of the pandemic led to …


Advanced Air Mobility Human Factors Considerations For Current Evtol Pilot Interfaces, Bhoomin B. Chauhan, Maria Chaparro Osman, Kendall Carmody, Meredith Carroll Jan 2023

Advanced Air Mobility Human Factors Considerations For Current Evtol Pilot Interfaces, Bhoomin B. Chauhan, Maria Chaparro Osman, Kendall Carmody, Meredith Carroll

National Training Aircraft Symposium (NTAS)

Advanced air mobility (AAM) is a novel transportation concept using electric vertical take-off and landing (eVTOL) aircraft to move people and cargo in urban and rural environments. The emergence of AAM has led to a range of different eVTOL vehicle designs at different stages in development, flight testing, and certification. Although these aircraft will serve similar markets, they will have different operational capabilities and pilot interfaces. These aircraft vary in whether they are (a) multi-rotor and have tilt-rotor capabilities, or (b) winged with tilt-wing capabilities, vectored thrust, fans, or propellers. The pilot interfaces in eVTOL align with the concept of …


The Value Of Strong Partnerships To Build A Successful Aviation Maintenance Career Pathway Program For Transitioning Military Service Members, Angela C. Albritton, Kenneth Witcher Ph.D., Christopher Toppin Jan 2023

The Value Of Strong Partnerships To Build A Successful Aviation Maintenance Career Pathway Program For Transitioning Military Service Members, Angela C. Albritton, Kenneth Witcher Ph.D., Christopher Toppin

National Training Aircraft Symposium (NTAS)

The aerospace industry is competing with other industries for a qualified workforce, and many of those competing industries are investing heavily in creating workforce development pipelines. Boeing (2021) forecasts that 626,000 new aviation maintenance technicians will be needed over the next 20 years. If the aerospace industry is unable to recruit the skilled workforce they require, it could have a ripple effect felt globally. Career pathway programs are emerging as essential to inspiring and recruiting the next generation of aviation professionals. How can industry, academia and government work together to find more innovative ways to address the growing need for …


Change Fatigue In Aviation Maintenance Through A Human Factors Lens, Stephanie Douglas, Bettina Mrusek Jan 2023

Change Fatigue In Aviation Maintenance Through A Human Factors Lens, Stephanie Douglas, Bettina Mrusek

National Training Aircraft Symposium (NTAS)

Aviation is a demanding and fast-paced industry and it is not uncommon for aviation professionals, including maintainers, to experience rapid disruption and organizational change. Fatigue in aviation professionals is a known risk. Fatigue risk management systems (FRMS) seek to mitigate this risk by focusing on tiredness resulting from long work hours and lack of quality sleep. Recently, change fatigue has also risen to the forefront of business and employee studies. In many of today’s industries, change is constant as firms implement changes either to address disruptions, business growth or to follow trends in the industry. Frequent changes in an organization …


Workforce Of The Future Begins With Aviation Stem, Lyndsay Digneo Jan 2023

Workforce Of The Future Begins With Aviation Stem, Lyndsay Digneo

National Training Aircraft Symposium (NTAS)

The United States has always been a world leader in aviation. This leadership position relies on the strength of the American STEM workforce and the quality of the nation’s educational, industrial, and government institutions. Therefore, it is imperative to nurture today’s students to become a well-trained STEM workforce in the future.

The Federal Aviation Administration (FAA) William J. Hughes Technical Center (WJHTC) recognizes that in pursuing its mission of aviation research, engineering, development, and test and evaluation, it is in a unique position to support aviation STEM activities for schools (K-12), post-secondary institutions, and community organizations. In 2016, the Technical …


Determining The Effectiveness Of Single-Pilot Resource Management In General Aviation, Alaba Gabriel Idowu, Holly Augustine, Michael Adebola Shogbonyo Jan 2023

Determining The Effectiveness Of Single-Pilot Resource Management In General Aviation, Alaba Gabriel Idowu, Holly Augustine, Michael Adebola Shogbonyo

National Training Aircraft Symposium (NTAS)

This research aims to determine the effectiveness of single-pilot resource management (SRM) towards improved safety in general aviation (GA) as compared to its counterpart, crew resource management (CRM), in commercial aviation that has improved commercial safety drastically. GA safety has been a significant concern due to many fatalities. Despite SRM concepts to ensure safe and successful flight operations, evidence showed that GA suffers a higher fatal accident rate than scheduled airline flights and holds a lackluster safety record, accounting for 94% of civil aviation fatalities. In contrast, commercial aviation safety has improved since the implementation of CRM. The investigation examines …


Why Should Airline Workers Be Trained To Respond To Fume Events?, Judith Tl Anderson Jan 2023

Why Should Airline Workers Be Trained To Respond To Fume Events?, Judith Tl Anderson

National Training Aircraft Symposium (NTAS)

The potential for engine oil and hydraulic fluid fumes to contaminate the ventilation air supplied to the aircraft cabin and flight deck has been recognized since the 1950s as a function of the design and maintenance of the bleed air system. The presence of oil and hydraulic fluid in the bleed air matters because the fumes contain complex mixtures of chemicals, including toxic additives. Starting in the 1950s and continuing to this day, crewmembers around the world have documented ill health during and after breathing these fumes. Also, some crewmembers have reported impairment and even incapacitation inflight, resulting in investigations …


Utilizing Drones To Streamline Wildlife Hazard Management Efforts By Airport Operators, Flavio A. C. Mendonca Ph.D., Ryan Wallace, Jose Cabrera, Cole Mcnall Jan 2023

Utilizing Drones To Streamline Wildlife Hazard Management Efforts By Airport Operators, Flavio A. C. Mendonca Ph.D., Ryan Wallace, Jose Cabrera, Cole Mcnall

National Training Aircraft Symposium (NTAS)

Airports operating under the Code of Federal Regulations Part 139 should conduct a wildlife hazard assessment (WHA) when some wildlife-strike events have occurred at or near the airport. The WHA must be conducted by a Qualified Airport Wildlife Biologist (QAWB). The required elements in a WHA include the identification of the wildlife species observed and their numbers, and the location of features on and near the airport that could attract wildlife. Service learning and research projects enable undergraduate students to develop transferable skills that are highly valued by the aviation industry, including critical thinking, self-confidence, the ability to integrate theory …


Development Of Upset Recovery And Basic Aerobatic Courses For Collegiate Flight Training Programs, Warren P. Pittorie, Michaela C. Satter, Meredith Carroll Phd Jan 2023

Development Of Upset Recovery And Basic Aerobatic Courses For Collegiate Flight Training Programs, Warren P. Pittorie, Michaela C. Satter, Meredith Carroll Phd

National Training Aircraft Symposium (NTAS)

Upset recovery and aerobatics are two topics in general aviation that are often overlooked by commercial pilots in training. This can be due to several different constraints, such as not having the time or resources to receive optional flight instruction, or the workload involved with locating a reputable school and qualified flight instructor. In addition, upset recovery and aerobatics training is not required to become a commercially rated pilot and start a career in the aviation industry. However, both topics, especially upset recovery, can increase a pilot’s awareness of the limitations of their own aircraft and increase their confidence when …


Development Of A Safety Performance Decision-Making Tool For Flight Training Organizations, Marisa D. Aguiar Phd, Carolina L. Anderson Phd Jan 2023

Development Of A Safety Performance Decision-Making Tool For Flight Training Organizations, Marisa D. Aguiar Phd, Carolina L. Anderson Phd

National Training Aircraft Symposium (NTAS)

The purpose of the research was to create and validate a safety performance decision-making tool to transform a reactive safety model into a predictive, decision-making tool, specific to large, collegiate Title 14 of the Code of Federal Regulations (CFR) Part 141 flight training organizations, to increase safety and aid in operational decision-making. Using Monte Carlo simulation, the study conducted simulation runs based on true operational ranges to simulate the operating conditions possible within large, collegiate CFR Part 141 flight training organizations with varying levels of controllable resources in terms of personnel (Aviation Maintenance Technicians and Instructor Pilots) and expenditures (active …


Airline Pilot Risk Profiling By Using Unstable Approach Management Case, Selim Ozyurek Jan 2023

Airline Pilot Risk Profiling By Using Unstable Approach Management Case, Selim Ozyurek

National Training Aircraft Symposium (NTAS)

Risk and human decision-making cannot be separated from each other. Many of theories and studies have tried to analyze pilots’ decision-making processes, risk factors, and preference behavior in the aviation domain. Unstable approaches are fairly infrequent, but an unstable approach is a major risk factor for landing accidents (Smith & Curtis, 2013; Smith, Jamieson, & Curtis, 2012). Therefore, the decision to execute a go-around if an approach is not sufficiently stable is encouraged in the interest of safety (Airbus Customer Services, 2012; Flight Safety Foundation, 2013), but in practice less than 5% of the unstable approaches actually results in a …


A Bidirectional Deep Lstm Machine Learning Method For Flight Delay Modelling And Analysis, Desmond B. Bisandu, Irene Moulitsas Jan 2023

A Bidirectional Deep Lstm Machine Learning Method For Flight Delay Modelling And Analysis, Desmond B. Bisandu, Irene Moulitsas

National Training Aircraft Symposium (NTAS)

Flight delays can be prevented by providing a reference point from an accurate prediction model because predicting flight delays is a problem with a specific space. Only a few algorithms consider predicted classes' mutual correlation during flight delay classification or prediction modelling tasks. None of these existing methods works for all scenarios. Therefore, the need to investigate the performance of more models in solving the problem of flight delay is vast and rapidly increasing. This paper presents the development and evaluation of LSTM and BiLSTM models by comparing them for a flight delay prediction. The LSTM does the feature extraction …


Integrated Organizational Machine Learning For Aviation Flight Data, Michael J. Pritchard, Paul Thomas, Eric Webb, Jon Martin, Austin Walden Jan 2023

Integrated Organizational Machine Learning For Aviation Flight Data, Michael J. Pritchard, Paul Thomas, Eric Webb, Jon Martin, Austin Walden

National Training Aircraft Symposium (NTAS)

An increased availability of data and computing power has allowed organizations to apply machine learning techniques to various fleet monitoring activities. Additionally, our ability to acquire aircraft data has increased due to the miniaturization of small form factor computing machines. Aircraft data collection processes contain many data features in the form of multivariate time-series (continuous, discrete, categorical, etc.) which can be used to train machine learning models. Yet, three major challenges still face many flight organizations 1) integration and automation of data collection frameworks, 2) data cleanup and preparation, and 3) embedded machine learning framework. Data cleanup and preparation has …


Factors Influencing Users’ Attitudes Towards Using Brain Computer Interface (Bci) For Non Medical Uses: An Application Of The Technology Acceptance Model (Tam), Yichin Wu, Leila Halawi Jan 2023

Factors Influencing Users’ Attitudes Towards Using Brain Computer Interface (Bci) For Non Medical Uses: An Application Of The Technology Acceptance Model (Tam), Yichin Wu, Leila Halawi

National Training Aircraft Symposium (NTAS)

While brain-computer interfaces (BCI) are gaining popularity in assisting people with illnesses, there is also increased technical research on incorporating BCI into healthy people’s lives. So far, not much research has focused on user attitudes, although some research has pointed out privacy and trust issues. Understanding potential users’ attitudes, expectations, and concerns early in the technology development stage is crucial for the novelty's success. For this reason, this study aims to understand the general publics’ attitude towards BCI for nonmedical uses using the technology acceptance model (TAM). The study will offer insights into how external factors including technology optimism, familiarity, …


Neutralization Of Fuel Tankering Emissions For Environmental Sustainability, Peter O'Reilly, Maria Petrescu, Fabricio Sulzbacher, Diogo Coutinho Jan 2023

Neutralization Of Fuel Tankering Emissions For Environmental Sustainability, Peter O'Reilly, Maria Petrescu, Fabricio Sulzbacher, Diogo Coutinho

National Training Aircraft Symposium (NTAS)

As aviation has been one of the fastest-growing sources of emissions, this paper explores sustainable solutions in the equation of the economic savings from the fuel tankering practice, in a way it could represent gains of credibility for this industry (Boussauw & Vanoutrive, 2019). The fuel expenses in Brazil have been responsible for the highest operational cost for the airlines and, as a result, there has been an ongoing pursuit of the highest level of efficiency (ANAC, 2019). In this context, this study has been focused on the emerging Brazilian aviation market, and uses primary data collected from three major …


Improved Feedback Mechanisms Of The Hydraulics Sandbox Simulator, Karen J. Johnson, Martin Hebel Jan 2023

Improved Feedback Mechanisms Of The Hydraulics Sandbox Simulator, Karen J. Johnson, Martin Hebel

National Training Aircraft Symposium (NTAS)

The proposed presentation will include the following project and results from implementation in an aircraft hydraulic systems course.

In 2020 we developed a digital hydraulics system schematic sandbox for use in an FAA Part 147 airframe maintenance technician training program (See Figure 1). The sandbox allows students to drag-drop-connect components used in systems such as those found in aircraft. It allows them to ‘test-connect’ the components to get feedback on correct and incorrect ‘construction’. As shown in Figure 1, light green ‘hoses’ are correct supply connections, dark green are correct return connections and red are incorrect connections per established rules …


Static And Dynamic Analysis Of A Bistable Frequency Up-Converter Piezoelectric Energy Harvester, Mohammad Atmeh, Alwathiqbellah Ibrahim, Abdallah Ramini Jan 2023

Static And Dynamic Analysis Of A Bistable Frequency Up-Converter Piezoelectric Energy Harvester, Mohammad Atmeh, Alwathiqbellah Ibrahim, Abdallah Ramini

Mechanical Engineering Faculty Publications and Presentations

Using energy harvesting to convert ambient vibrations efficiently to electrical energy has become a worthy concept in recent years. Nevertheless, the low frequencies of the ambient vibrations cannot be effectively converted to power using traditional harvesters. Therefore, a frequency up-conversion harvester is presented to convert the low-frequency vibrations to high-frequency vibrations utilizing magnetic coupling. The presented harvester consists of a low-frequency beam (LFB) and a high-frequency beam (HFB) with identical tip magnets facing each other at the same polarity. The HFB, fully covered by a piezoelectric strip, is utilized for voltage generation. The dynamic behavior of the system and the …


Adsorptive Properties And On-Demand Magnetic Response Of Lignin@Fe3o4 Nanoparticles At Castor Oil–Water Interfaces, Mohammad J. Hasan, Emily Westphal, Peng Chen, Abishek Saini, I-Wei Chu, Sarah J. Watzman, Esteban E. Ureña-Benavides, Erick S. Vasquez Jan 2023

Adsorptive Properties And On-Demand Magnetic Response Of Lignin@Fe3o4 Nanoparticles At Castor Oil–Water Interfaces, Mohammad J. Hasan, Emily Westphal, Peng Chen, Abishek Saini, I-Wei Chu, Sarah J. Watzman, Esteban E. Ureña-Benavides, Erick S. Vasquez

Chemical and Materials Engineering Faculty Publications

Lignin@Fe3O4 nanoparticles adsorb at oil–water interfaces, form Pickering emulsions, induce on-demand magnetic responses to break emulsions, and can sequester oil from water. Lignin@Fe3O4 nanoparticles were prepared using a pH-induced precipitation method and were fully characterized. These were used to prepare Pickering emulsions with castor oil/Sudan red G dye and water at various oil/water volume ratios and nanoparticle concentrations. The stability and demulsification of the emulsions under different magnetic fields generated with permanent magnets (0–540 mT) were investigated using microscopy images and by visual inspection over time. The results showed that the Pickering emulsions were more stable at the castor oil/water …


Advanced Air Mobility Human Factors Considerations For Current Evtol Pilot Interfaces, Bhoomin B. Chauhan, Maria Chaparro Osman, Kendall Carmody, Meredith Carroll Jan 2023

Advanced Air Mobility Human Factors Considerations For Current Evtol Pilot Interfaces, Bhoomin B. Chauhan, Maria Chaparro Osman, Kendall Carmody, Meredith Carroll

Aeronautics Faculty Publications

Advanced air mobility (AAM) is a novel transportation concept using electric vertical take-off and landing (eVTOL) aircraft to move people and cargo in urban and rural environments. The emergence of AAM has led to a range of different eVTOL vehicle designs at different stages in development, flight testing, and certification. Although these aircraft will serve similar markets, they will have different operational capabilities and pilot interfaces. These aircraft vary in whether they are (a) multi-rotor and have tilt-rotor capabilities, or (b) winged with tilt-wing capabilities, vectored thrust, fans, or propellers. The pilot interfaces in eVTOL align with the concept of …


A Cohort Retrospective Study Of Framingham Score And Ecg Abnormality Among Coal Mining Workers, Faizal Ablansah Anandita, Isman Firdaus, Rino Alvani Gani, Retno Asti Werdhani, Muchtaruddin Mansyur Jan 2023

A Cohort Retrospective Study Of Framingham Score And Ecg Abnormality Among Coal Mining Workers, Faizal Ablansah Anandita, Isman Firdaus, Rino Alvani Gani, Retno Asti Werdhani, Muchtaruddin Mansyur

Occupational and Environmental Medicine Journal of Indonesia

Introduction. ECG is widely used for detecting cardiovascular disease in coal mine worker’s medical check-up. As the study has proven, coal mine workers have a double cardiovascular risk from their workplace hazard and their own medical risks as individuals. An early detection and risk assessment method is needed to predict ECG abnormalities in the future. This study will analyze the relationship between ECG abnormality and Framingham Risk Score on coal mine workers’. Methods. We examine ECG result from medical check-up of male coal worker during 2018 and 2021. Using Minnesota Code, we determine ECG abnormality categories in the 2021 result, …


Artificial Intelligence Assisted Residual Strength And Life Prediction Of Fiber Reinforced Polymer Composites, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian, Vamsee Vadlamudi, Rassel Raihan Jan 2023

Artificial Intelligence Assisted Residual Strength And Life Prediction Of Fiber Reinforced Polymer Composites, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)-Archive

With the increased use of composite materials, researchers have developed many approaches for structural and prognostic health monitoring. Broadband Dielectric Spectroscopy (BbDS)/Impedance Spectroscopy (IS) is a state-of-the-art technology that can be used to identify and monitor the minute changes in damage initiation, accumulation, interactions, and the degree of damage in a composite under static and dynamic loading. This work presents a novel artificial neural network (ANN) framework for fiber-reinforced polymer (FRP) composites under fatigue loading, which incorporates dielectric state variables to predict the life (durability) and residual strength (damage tolerance) from real-time acquired dielectric permittivity of the material. The findings …


Electric Field-Assisted Nanofiltration For Pfoa Removal With Exceptional Flux, Selectivity, And Destruction, Yangyuan Ji, Youn Jeong Choi, Yuhang Fang, Hoang Son Pham, Alliyan Tan Nou, Linda S. Lee, Junfeng Niu, David M. Warsinger Jan 2023

Electric Field-Assisted Nanofiltration For Pfoa Removal With Exceptional Flux, Selectivity, And Destruction, Yangyuan Ji, Youn Jeong Choi, Yuhang Fang, Hoang Son Pham, Alliyan Tan Nou, Linda S. Lee, Junfeng Niu, David M. Warsinger

School of Mechanical Engineering Faculty Publications

Per- and polyfluoroalkyl substances (PFAS) pose significant environmental and human health risks and thus require solutions for their removal and destruction. However, PFAS cannot be destroyed by widely used removal processes like nanofiltration (NF). A few scarcely implemented advanced oxidation processes can degrade PFAS. In this study, we apply an electric field to a membrane system by placing a nanofiltration membrane between reactive electrodes in a crossflow configuration. The performance of perfluorooctanoic acid (PFOA) rejection, water flux, and energy consumption were evaluated. The reactive and robust SnO2–Sb porous anode was created via a sintering and sol–gel process. The characterization and …


An Alternate Dimensionless Form Of The Linearized Rigid-Body Aircraft Equations Of Motion With Emphasis On Dynamic Parameters, Douglas F. Hunsaker, Benjamin C. Moulton Jan 2023

An Alternate Dimensionless Form Of The Linearized Rigid-Body Aircraft Equations Of Motion With Emphasis On Dynamic Parameters, Douglas F. Hunsaker, Benjamin C. Moulton

Mechanical and Aerospace Engineering Student Publications and Presentations

The equations of motion for an aircraft can be linearized about a reference condition within the assumptions of small disturbances and linear aerodynamics. The resulting system of equations is typically solved to obtain the eigenvalues and eigenvectors that describe the small disturbance motion of the aircraft. Results from such an analysis are often used to predict the rigid-body dynamic modes of the aircraft and associated handling qualities. This process is typically carried out in dimensional form in most text books, or in nondimensional form using dimensionless parameters rooted in aerodynamic theory. Here we apply Buckingham’s Pi theorem to obtain nondimensional …


Microcontrollers To Teach Automation Basics, Jonathan Shimon Jan 2023

Microcontrollers To Teach Automation Basics, Jonathan Shimon

Symposium on Education in Entertainment and Engineering

Microcontrollers to Teach Automation Basics Introducing students to the fundamentals of automation can be a massive undertaking for faculty. Scenic automation systems can be very complex in order to prepare students for this emerging area of technical theatre it behooves faculty to find innovative ways to fit the foundations and concepts into curriculum. Many automation solutions exist on the market, from plug and play to component level they are all in the thousands of dollar and take up significant space. It would be impractical for each student in an undergraduate program to have their own system. Arduino microcontrollers that incorporate …


Artificial Intelligence For Automated Detection Of Large Mammals Creates Path To Upscale Drone Surveys, Javier Lenzi, Andrew Barnas, Abdelrahman A. Elsaid, Travis Desell, Robert F. Rockwell, Susan N. Ellis-Felege Jan 2023

Artificial Intelligence For Automated Detection Of Large Mammals Creates Path To Upscale Drone Surveys, Javier Lenzi, Andrew Barnas, Abdelrahman A. Elsaid, Travis Desell, Robert F. Rockwell, Susan N. Ellis-Felege

Biology Faculty Publications

Imagery from drones is becoming common in wildlife research and management, but processing data efficiently remains a challenge. We developed a methodology for training a convolutional neural network model on large-scale mosaic imagery to detect and count caribou (Rangifer tarandus), compare model performance with an experienced observer and a group of naïve observers, and discuss the use of aerial imagery and automated methods for large mammal surveys. Combining images taken at 75 m and 120 m above ground level, a faster region-based convolutional neural network (Faster-RCNN) model was trained in using annotated imagery with the labels: “adult …


Interfaces In Dynamic Brittle Fracture Of Pmma: A Peridynamic Analysis, Longzhen Wang, Javad Mehrmashhadi, Florin Bobaru Jan 2023

Interfaces In Dynamic Brittle Fracture Of Pmma: A Peridynamic Analysis, Longzhen Wang, Javad Mehrmashhadi, Florin Bobaru

Department of Mechanical and Materials Engineering: Faculty Publications

Recent experiments in bonded PMMA layers have shown dramatic changes in dynamic crack growth characteristics depending on the interface location and toughness. In this paper we present a peridynamic (PD) analysis of this phenomenon and determine three elements that are essential in a model reproducing the observed fracture behavior: (1) softening near the crack tip to account for changes in PMMA due to heat-generation induced by the high strain rates reached around the crack tip in dynamic fracture; (2) independent extension (mode I) and shear (mode II) modes of fracture; (3) a two-parameter fracture model, which matches both strength and …


Research On Mixed Flow Line Balancing And Scheduling Optimization With Multiple Constraints, Zhenping Li, Ying Shi, Lingyun Wu Jan 2023

Research On Mixed Flow Line Balancing And Scheduling Optimization With Multiple Constraints, Zhenping Li, Ying Shi, Lingyun Wu

Journal of System Simulation

Abstract: Aiming at the phenomena of unbalanced load between stations and product accumulation caused by unreasonable design of mixed flow line in G enterprise, based on the matching relationship between processes and stations, cycle time, process priority and other constraint, with the objectives of reducing the number of stations, balancing the workload between stations, and reducing the products waiting time, a multi-objective mixed integer programming model for mixed flow line balance and product scheduling problem is established. A hierarchical algorithm and a hybrid heuristic algorithm are designed respectively; the accuracy of the hierarchical algorithm is verified by small-scale …


Research On Modeling And Simulation Of Application Efficiency Of Tactical Medical Equipment, Guowei Lu, Xueqiang Tao, Deguang Duan, Hao Li, Zerui Zhang, En Chen Jan 2023

Research On Modeling And Simulation Of Application Efficiency Of Tactical Medical Equipment, Guowei Lu, Xueqiang Tao, Deguang Duan, Hao Li, Zerui Zhang, En Chen

Journal of System Simulation

Abstract: In view of the lack of effective modeling and simulation means for the current research on the application efficiency of tactical medical treatment equipment in our army, a modeling and simulation research framework for the application effectiveness of equipment through the wounded model, equipment model and evaluation model is constructed. Based on the multi-agent method in Anylogic8.7.0 modeling and simulation platform, the casualty generation and its circulation process among medical treatment equipment are simulated. In the context of a tactical medical exercis, the overall support capability of medical treatment equipment is evaluated scientifically and quantitatively, and the key equipment …


Development Opportunities And Application Prospects Of Aero-Engine Simulation Technology Under Digital Transformation, Jianguo Cao Jan 2023

Development Opportunities And Application Prospects Of Aero-Engine Simulation Technology Under Digital Transformation, Jianguo Cao

Journal of System Simulation

Abstract: The development of China's social economy and the improvement of its national defense capability in the new era put forward higher requirements for the development of aero-engines. It is urgent to promote the digital transformation of aero-engines in order to achieve coordinated, agile and efficient aero-engine development. Based on the current research and development of aero-engine in China, this paper clarifies the new connotation of "speediness and efficiency, accurate mapping, comprehensive coverage, and dynamic prediction" given by the development of emerging cutting-edge technologies to aero-engine simulation technology, as well as the new technical features of "spatio-temporal ubiquity, data driven, …