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Full-Text Articles in Engineering

That Bike Is Too Heavy: Merging Bicycling Physics, Human Physiology And Travel Behavior, Alexander Y. Bigazzi May 2019

That Bike Is Too Heavy: Merging Bicycling Physics, Human Physiology And Travel Behavior, Alexander Y. Bigazzi

PSU Transportation Seminars

Are the Biketown bikes too heavy? Does better gear motivate people to cycle more? How much faster will someone go on an e-bike?

Although urban cycling is widely known as physically active transportation, the actual physics of cycling have been given little attention in transportation engineering and planning. In contrast, the field of sports science has developed detailed data and models of road bicycle performance, but only for sport and racing cyclists.

What can we learn about utilitarian cycling by integrating knowledge of the physical attributes of bicycles and cyclists?

This seminar examines the ways in which bicycle physics, and …


Simultaneous Estimation Of Ocean Tides And Underwater Topography In The Weddell Sea, Edward D. Zaron May 2019

Simultaneous Estimation Of Ocean Tides And Underwater Topography In The Weddell Sea, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

A new model for theM2, S2, K1, and O1 tides in the Weddell Sea is developed by assimilating CryoSat-2 data into a barotropic tide model. A variational approach is used, which explicitly allows for errors in the water depth, that is, the bottom topography in open water and the water column thickness under floating ice shelves, so that an optimized estimate of the topography is obtained together with the tidal fields. In preparation for assimilation, the sensitivity of the tidal elevation to the interfacial drag at the sea floor and the ice-water interface (under the floating ice shelves) is investigated; …


Fatigue Characteristics Of New Eco Series Aluminum 7175 Alloy, Chinh Q.L. Vu May 2019

Fatigue Characteristics Of New Eco Series Aluminum 7175 Alloy, Chinh Q.L. Vu

Dissertations and Theses

In this dissertation, the fatigue characteristics of three newly developed experimental compositions for aluminum 7175, with improved mechanical strength, that uses magnesium-calcium alloy instead of pure magnesium are studied.

Specimens of each variant were fabricated and subjected to fatigue life testing, fatigue life data analysis, and observation of their fracture characteristics through optical microscopy and scanning electron microscopy (SEM), and metallography to study their grains and surface characteristics.

Fatigue life testing shows all three variants have a fatigue strength that is approaching approximately 200 MPa. ECO7175v3 is shown to have the highest fatigue strength of approximately 220 MPa at 5x10 …


An Agent-Based Evacuation Model To Improve Safety In The Cascadia Subduction Zone, Haizhong Wang Apr 2019

An Agent-Based Evacuation Model To Improve Safety In The Cascadia Subduction Zone, Haizhong Wang

PSU Transportation Seminars

This seminar will present ongoing research into how integrated social, natural, and engineered systems can improve life safety under threat of multi-hazards. The targeted scenario is a magnitude 9.0 earthquake and tsunami from the Cascadia Subduction Zone, threatening communities along 1,000 miles of the US Pacific Northwest coastline.

Since the mid-1980’s scientific evidence has underscored the possibility of such an extreme event, and it has taken at least another decade or more before public attitudes and policy have begun to adapt to this new hazard. Life safety is a pressing issue for the near-field CSZ tsunami hazard for several reasons. …


Design And Performance Evaluation Of Linear And Axial-Flux Magnetic Gears, Mojtaba Bahrami Kouhshahi Apr 2019

Design And Performance Evaluation Of Linear And Axial-Flux Magnetic Gears, Mojtaba Bahrami Kouhshahi

Dissertations and Theses

The conversion from low speed to high speed and vice versa in various forms, including rotary and linear motion, is a requirement for a wide range of applications. For example, wind power generation requires a conversion of low speed rotation of turbine blades to high speed generator rotation, and ocean wave power generation is achievable by conversion of low speed linear motion to either high speed rotation or high speed linear motion. Mechanical gearboxes, hydraulic and pneumatic actuators are commonly used to achieve these conversions. However, these systems suffer from reliability issues, high maintenance requirements, noise, and lack of overload …


X-Ray Determination Of Compressive Residual Stresses In Spring Steel Generated By High-Speed Water Quenching, Diego E. Lozano, George E. Totten, Yaneth Bedolla-Gil, Martha Guerrero-Mata, Marcel Carpio, Gabriela M. Martinez-Cazares Apr 2019

X-Ray Determination Of Compressive Residual Stresses In Spring Steel Generated By High-Speed Water Quenching, Diego E. Lozano, George E. Totten, Yaneth Bedolla-Gil, Martha Guerrero-Mata, Marcel Carpio, Gabriela M. Martinez-Cazares

Mechanical and Materials Engineering Faculty Publications and Presentations

Automotive components manufacturers use the 5160 steel in leaf and coil springs. The industrial heat treatment process consists in austenitizing followed by the oil quenching and tempering process. Typically, compressive residual stresses are induced by shot peening on the surface of automotive springs to bestow compressive residual stresses that improve the fatigue resistance and increase the service life of the parts after heat treatment. In this work, a high-speed quenching was used to achieve compressive residual stresses on the surface of AISI/SAE 5160 steel samples by producing high thermal gradients and interrupting the cooling in order to generate a case-core …


Exoskeleton, Vinu Casper, Liliana Fitzpatrick Apr 2019

Exoskeleton, Vinu Casper, Liliana Fitzpatrick

Engineering and Technology Management Student Projects

This is a research about the marketing plan for exoskeleton wearable devices. The objective is to provide a meaningful Customer Value Proposition to the prospective customers.The Samsung company SWOT analysis is the basis for a marketing strategy. The exoskeleton features and market definition is included in the analysis. A competitor analysis of homogeneus exoskeletons providers is included to review the current market. An exhaustive customer analysis was performed to identify the customer needs as the input for the marketing plan development. The potential market was identified to learn about the exoskeleton market share opportunity. The exoskeleton global market is analyzed …


Analysis And Application Of Log-Linear And Quantile Regression Models To Predict Bus Dwell Times, Travis B. Glick, Miguel Figliozzi Apr 2019

Analysis And Application Of Log-Linear And Quantile Regression Models To Predict Bus Dwell Times, Travis B. Glick, Miguel Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Understanding the key factors that contribute to transit travel times and travel time variability is an essential part of transit planning and research. Delay that occurs when buses service bus stops, dwell time, is one of the main sources of travel time variability and has therefore been the subject of ongoing research to identify and quantify its determinants. Previous research has focused on testing new variables using linear regressions that may be added to models to improve predictions. An important assumption of linear regression models used in past research efforts is homoscedasticity or the equal distribution of the residuals across …


Integrating Landsat Tm/Etm+ And Numerical Modeling To Estimatewater Temperature In The Tigris River Under Future Climate And Management Scenarios, Muhanned Al-Murib, Scott Wells, Stefan Talke Apr 2019

Integrating Landsat Tm/Etm+ And Numerical Modeling To Estimatewater Temperature In The Tigris River Under Future Climate And Management Scenarios, Muhanned Al-Murib, Scott Wells, Stefan Talke

Civil and Environmental Engineering Faculty Publications and Presentations

Modeling the water quality of rivers and assessing the effects of changing conditions is often hindered by a lack of in situ measurements for calibration. Here, we use a combination of satellite measurements, statistical models, and numerical modeling with CE-QUAL-W2 to overcome in situ data limitations and evaluate the effect of changing hydrologic and climate conditions on water temperature (Tw) in the Tigris River, one of the largest rivers in the Middle East. Because few in situ estimates of Tw were available, remotely-sensed estimates of Tw were obtained from Landsat satellite images at roughly 2 week intervals for …


The Applications Of Grid Cells In Computer Vision, Keaton Kraiger Apr 2019

The Applications Of Grid Cells In Computer Vision, Keaton Kraiger

Maseeh Summer Undergraduate Research Experience

In this study we present a novel method for position and scale invariant object representation based on a biologically-inspired framework. Grid cells are neurons in the entorhinal cortex whose multiple firing locations form a periodic triangular array, tiling the surface of an animal’s environment. We propose a model for simple object representation that maintains position and scale invariance, in which grid maps capture the fundamental structure and features of an object. The model provides a mechanism for identifying feature locations in a Cartesian plane and vectors between object features encoded by grid cells. It is shown that key object features …


A Study Of Thermal Energy Storage Of Phase Change Materials: Thermophysical Properties And Numerical Simulations, Kyung-Eun Min Apr 2019

A Study Of Thermal Energy Storage Of Phase Change Materials: Thermophysical Properties And Numerical Simulations, Kyung-Eun Min

Dissertations and Theses

A Thermal Energy Storage (TES) system is meant for holding thermal energy in the form of hot or cold materials for later utilization. A TES system is an important technological system in providing energy savings as well as efficient and optimum energy use. The main types of a TES system are sensible heat and latent heat. A latent heat storage is a very efficient method for storing or releasing thermal energy due to its high energy storage density at constant temperatures, and a latent heat storage material can store 5-14 times more heat per unit volume than a sensible heat …


Investigation Of Electronic And Optical Properties Of 2-Dimensional Semiconductor Tin Selenide (Snse) Thin Films, Shakila Afrin Mar 2019

Investigation Of Electronic And Optical Properties Of 2-Dimensional Semiconductor Tin Selenide (Snse) Thin Films, Shakila Afrin

Dissertations and Theses

Over the last 5 decades, the semiconductor industry has been well served by Si based technology due to its abundant availability, lower manufacturing cost, large wafer sizes and less complexity in fabrication. Over this period, electronic devices and integrated systems have been miniaturized by downscaling of the transistors. The miniaturization has been guided by the Moore's law where the numbers of transistors have doubled over every two years. However, the trend of transistor miniaturization is fast approaching its limit. Hence, alternate and innovative solutions are necessary to tackle this problem and this propels the research for finding novel materials with …


Production Of Secondary Organic Aerosol During Aging Of Biomass Burning Smoke From Fresh Fuels And Its Relationship To Voc Precursors, A. T. Ahern, E. S. Robinson, D. S. Tkacik, L. E. Hatch, Kelley Barsanti, C. E. Stockwell, Robert J. Yokelson, Multiple Additional Authors Mar 2019

Production Of Secondary Organic Aerosol During Aging Of Biomass Burning Smoke From Fresh Fuels And Its Relationship To Voc Precursors, A. T. Ahern, E. S. Robinson, D. S. Tkacik, L. E. Hatch, Kelley Barsanti, C. E. Stockwell, Robert J. Yokelson, Multiple Additional Authors

Civil and Environmental Engineering Faculty Publications and Presentations

After smoke from burning biomass is emitted into the atmosphere, chemical and physical processes change the composition and amount of organic aerosol present in the aged, diluted plume. During the fourth Fire Lab at Missoula Experiment, we performed smog‐chamber experiments to investigate formation of secondary organic aerosol (SOA) and multiphase oxidation of primary organic aerosol (POA). We simulated atmospheric aging of diluted smoke from a variety of biomass fuels while measuring particle composition using high‐resolution aerosol mass spectrometry. We quantified SOA formation using a tracer ion for low‐volatility POA as a reference standard (akin to a naturally occurring internal standard). …


The Quest For Model Uncertainty Quantification: A Hybrid Ensemble And Variational Data Assimilation Framework, Peyman Abbaszadeh, Hamid Moradkhani, Dacian Daescu Mar 2019

The Quest For Model Uncertainty Quantification: A Hybrid Ensemble And Variational Data Assimilation Framework, Peyman Abbaszadeh, Hamid Moradkhani, Dacian Daescu

Civil and Environmental Engineering Faculty Publications and Presentations

This article presents a novel approach to couple a deterministic four‐dimensional variational (4DVAR) assimilation method with the particle filter (PF) ensemble data assimilation system, to produce a robust approach for dual‐state‐parameter estimation. In our proposed method, the Hybrid Ensemble and Variational Data Assimilation framework for Environmental systems (HEAVEN), we characterize the model structural uncertainty in addition to model parameter and input uncertainties. The sequential PF is formulated within the 4DVAR system to design a computationally efficient feedback mechanism throughout the assimilation period. In this framework, the 4DVAR optimization produces the maximum a posteriori estimate of state variables at the beginning …


On The Drought Recovery And Resiliency: How Terrestrial And Riverine Ecosystems Recover From Agricultural And Hydrological Droughts, Behzad Ahmadi Mar 2019

On The Drought Recovery And Resiliency: How Terrestrial And Riverine Ecosystems Recover From Agricultural And Hydrological Droughts, Behzad Ahmadi

Dissertations and Theses

Climate extremes, in particular droughts are significant driving forces towards riverine and terrestrial ecosystems disturbance. Drought impacts on stream ecosystems include losses that can either be direct (e.g. destruction of habitat for aquatic species) or indirect (e.g. deterioration of water quality, soil quality, and increased chance of wildfires). This study investigates hydrological and agricultural droughts and their recovery durations. For the riverine ecosystems, this study combines hydrologic drought and water quality changes during droughts and represents a multi-stage framework to detect and characterize hydrological droughts, while considering water quality parameters. Hydrological droughts are categorized into three stages of growth, persistence, …


Efficient Methods For Robust Circuit Design And Performance Optimization For Carbon Nanotube Field Effect Transistors, Muhammad Ali Mar 2019

Efficient Methods For Robust Circuit Design And Performance Optimization For Carbon Nanotube Field Effect Transistors, Muhammad Ali

Dissertations and Theses

Carbon nanotube field-effect transistors (CNFETs) are considered to be promising candidate beyond the conventional CMOSFET due to their higher current drive capability, ballistic transport, lesser power delay product and higher thermal stability. CNFETs show great potential to build digital systems on advanced technology nodes with big benefits in terms of power, performance and area (PPA). Hence, there is a great need to develop proven models and CAD tools for performance evaluation of CNFET-based circuits. CNFETs specific parameters, such as number of tubes, pitch (spacing between the tubes) and diameter of CNTs determine current driving capability, speed, power consumption and area …


Behavior Of Non-Ductile Slender Reinforced Concrete Columns Retrofit By Cfrp Under Cyclic Loading, Wisam Amer Aules Mar 2019

Behavior Of Non-Ductile Slender Reinforced Concrete Columns Retrofit By Cfrp Under Cyclic Loading, Wisam Amer Aules

Dissertations and Theses

In the Middle East region and many countries in the world, older reinforced concrete (RC) columns are deemed to be weak in seismic resistance because of their low amount of reinforcement, low grades of concrete, and large spacing between the transverse reinforcement. The capacity of older RC columns that are also slender is further reduced due to the secondary moments. Appropriate retrofit techniques can improve the capacity and behavior of concrete members. In this study, externally bonded Carbon Fiber Reinforced Polymer (CFRP) retrofit technique was implemented to improve the behavior of RC columns tested under constant axial load and cyclic …


Seismic Behavior Of Screen Grid Core Insulated Concrete Form Walls, Anwer Sabah Mohammed Mohammed Mar 2019

Seismic Behavior Of Screen Grid Core Insulated Concrete Form Walls, Anwer Sabah Mohammed Mohammed

Dissertations and Theses

The use of the insulated concrete form (ICF) walls in residential buildings has increased over the past few decades. Much research has been conducted to evaluate the lateral strength of these walls by applying monotonic and cyclic loadings. In the current study, full-scale shake table experiments were employed to evaluate the in-plane behavior of four screen grid insulated concrete form (SGICF) walls. The first two wall specimens utilized dry fit insulated form blocks made from recycled expanded polystyrene granules that were bonded together with cement. When stacked, the cavities in the blocks formed a grid of cores that are evenly …


Managing Healthcare Data Assets As A Complex Adaptive System, Katie Clifton Mar 2019

Managing Healthcare Data Assets As A Complex Adaptive System, Katie Clifton

Systems Science Friday Noon Seminar Series

A major project is underway to develop a shared platform for data and analytics in a highly federated healthcare delivery organization. In the status quo data environment, analysts have integrated information from various domains — medical records, claims, membership — to produce a multitude of reports and analysis. Duplicative, mis-aligned, and siloed datasets were created as an unintended consequence.

One objective of the project is to produce outcomes (reports, analysis) that are more standardized and efficient than the status quo without sacrificing adaptability. Standards and practices are being intentionally developed as a mechanism for this emerging system to achieve more …


Challenges In Designing A Mentorship Program For Electrical Engineering Freshmen, Branimir Pejcinovic, Melinda Holtzman Mar 2019

Challenges In Designing A Mentorship Program For Electrical Engineering Freshmen, Branimir Pejcinovic, Melinda Holtzman

Electrical and Computer Engineering Faculty Publications and Presentations

This Work in Progress Innovative Practice Paper addresses three challenges we face when teaching freshmen: a) how to present a wide variety of sub-fields in electrical engineering, b) how to establish the relevance of electrical engineering to things they care about, and c) how to relate electrical engineering to students' experiences. We are attempting to address these through a mentorship program involving recent alumni working with teams of freshman electrical engineering students. Mentors are expected to: (i) come to class and speak about their job experience, (ii) meet with their teams early in the term to help them get started …


Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle Mar 2019

Remote Sensing Of Water Use Efficiency And Terrestrial Drought Recovery Across The Contiguous United States, Behzad Ahmadi, Ali Ahmadalipour, Glenn Tootle

Civil and Environmental Engineering Faculty Publications and Presentations

Ecosystem water-use efficiency (WUE) is defined as the ratio of carbon gain (i.e., gross primary productivity; GPP) to water consumption (i.e., evapotranspiration; ET). WUE is markedly influential on carbon and water cycles, both of which are fundamental for ecosystem state, climate and the environment. Drought can affect WUE, subsequently disturbing the composition and functionality of terrestrial ecosystems. In this study, the impacts of drought on WUE and its components (i.e., GPP and ET) are assessed across the Contiguous US (CONUS) at fine spatial and temporal resolutions. Soil moisture simulations from land surface modeling are utilized to detect and characterize agricultural …


Hydrological Drought Persistence And Recovery Over The Conus: A Multi-Stage Framework Considering Water Quantity And Quality, Behzad Ahmadi, Ali Ahmadalipour, Hamid Moradkhani Mar 2019

Hydrological Drought Persistence And Recovery Over The Conus: A Multi-Stage Framework Considering Water Quantity And Quality, Behzad Ahmadi, Ali Ahmadalipour, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Hydrological droughts have considerable negative impacts on water quantity and quality, and understanding their regional characteristics is of crucial importance. This study presents a multi-stage framework to detect and characterize hydrological droughts considering both streamflow and water quality changes. Hydrological droughts are categorized into three stages of growth, persistence, retreat, and water quality variables (i.e., water temperature, dissolved oxygen concentration, and turbidity) are utilized to further investigate drought recovery. The framework is applied to 400 streamflow gauges across the Contiguous United States (CONUS) over the study period of 1950–2016. The method is illustrated for the 2012 US drought, which affected …


To Burn-In, Or Not To Burn-In: That’S The Question, Ephraim Suhir Mar 2019

To Burn-In, Or Not To Burn-In: That’S The Question, Ephraim Suhir

Mechanical and Materials Engineering Faculty Publications and Presentations

In this paper it is shown that the bathtub-curve (BTC) based time-derivative of the failure rate at the initial moment of time can be considered as a suitable criterion of whether burn-in testing (BIT) should or does not have to be conducted. It is also shown that the above criterion is, in effect, the variance of the random statistical failure rate (SFR) of the mass-produced components that the product manufacturer received from numerous vendors, whose commitments to reliability were unknown, and their random SFR might vary therefore in a very wide range, from zero to infinity. A formula for the …


Effects Of Steel Type And Sandblasting Pretreatment On The Solid-Liquid Compound Casting Characteristics Of Zinc-Coated Steel/Aluminum Bimetals, Jesik Shin, Taehyeong Kim, Kyoungmook Lim, Hoon Cho, Daeho Yang, Changyeol Jeong, Sung Yi Mar 2019

Effects Of Steel Type And Sandblasting Pretreatment On The Solid-Liquid Compound Casting Characteristics Of Zinc-Coated Steel/Aluminum Bimetals, Jesik Shin, Taehyeong Kim, Kyoungmook Lim, Hoon Cho, Daeho Yang, Changyeol Jeong, Sung Yi

Mechanical and Materials Engineering Faculty Publications and Presentations

Effects of zinc-coated steel type and steel surface sandblasting pretreatment in the solid-liquid compound casting of layered type steel/aluminum bimetals were investigated. The Zn coating behavior and its effects on interfacial microstructure evolution and fracture mechanism were also discussed. The aluminum fluidity in thin plate type flow channels formed by the steel insert and the mold wall primarily depended on the insert surface roughness and secondarily on the wettability. As-galvanized (GI) steel/aluminum bimetal joints showed the bonding strength of 20 MPa and more, while galvannealed (GA) steels showed poor bonding. The interfacial bonding zone consisted of most Al13Fe4, Al8Fe2Si, Al4.5FeSi …


Webinar: Rethinking Streets For Bikes: An Evidence Based Guide Of Bike-Friendly Street Retrofits, Marc Schlossberg, Roger Lindgren Feb 2019

Webinar: Rethinking Streets For Bikes: An Evidence Based Guide Of Bike-Friendly Street Retrofits, Marc Schlossberg, Roger Lindgren

TREC Webinar Series

There is a growing demand for better infrastructure and fewer barriers to biking and other forms of space-efficient micromobility. Tackling daily trips by bike is easier on the environment, healthier for users and non-users alike, uses precious urbanized public and private land more efficiently, costs taxpayers less to build and maintain infrastructure, and when routes are safe and comfortable, moving by bike is also fun! Complete Streets policies are being adopted across the country, and there is an active conversation around the safety imperative of a Complete Streets approach. Yet, local officials often need both design guidance and the …


Iot And Digitization Will Reconnect System Engineering And Science, John Blyler Feb 2019

Iot And Digitization Will Reconnect System Engineering And Science, John Blyler

Systems Science Friday Noon Seminar Series

The fully connected world is quickly becoming a reality. Architects and developers of this new world must understand both the hardware and software basics of IoT and IIoT systems as well as the proven way to deal with the complexities of the integration of sensors, processors, wireless connectivity, edge to cloud networks, data partitioning and processing, AI, machine language, digital threads and twins, and much more. Such complexity can only be handled with a systems-of-systems (SoS) engineering approach.

But while systems engineering may hold many of the solutions to IoT challenges, systems engineering must evolve from its traditional role. Some …


Maximum Coverage Capacitated Facility Location Problem With Range Constrained Drones, Darshan Chauhan, Avinash Unnikrishnan, Miguel Figliozzi Feb 2019

Maximum Coverage Capacitated Facility Location Problem With Range Constrained Drones, Darshan Chauhan, Avinash Unnikrishnan, Miguel Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Given a set of demand and potential facility locations and a set of fully available charged drones, an agency seeks to locate a pre-specified number of capacitated facilities and assign drones to the located facilities to serve the demands. The facilities serve as drone launching sites for distributing the resources. Each drone makes several one-to-one trips from the facility location to the demand points and back until the battery range is met. The planning period is short-term and therefore the recharging of drone batteries is not considered. This paper presents an integer linear programming formulation with the objective of maximizing …


Parallelized Particle Swarm Optimization To Estimate The Heat Transfer Coefficients Of Palm Oil, Canola Oil, Conventional, And Accelerated Petroleum Oil Quenchants, Zoltán Fried, Imre Felde, Rosa L. Simencio Otero, Jônatas M. Viscaino, George E. Totten, Lauralice Canale Feb 2019

Parallelized Particle Swarm Optimization To Estimate The Heat Transfer Coefficients Of Palm Oil, Canola Oil, Conventional, And Accelerated Petroleum Oil Quenchants, Zoltán Fried, Imre Felde, Rosa L. Simencio Otero, Jônatas M. Viscaino, George E. Totten, Lauralice Canale

Mechanical and Materials Engineering Faculty Publications and Presentations

An inverse solver for the estimation of the temporal-spatial heat transfer coefficients (HTC), without using prior information of the thermal boundary conditions, was used for immersion quenching into palm oil, canola oil, and two commercial petroleum oil quenchants. The particle swarm optimization (PSO) method was used on near-surface temperature-time cooling curve data obtained with the so-called Tensi multithermocouple, and a 12.5 by 45 mm Inconel 600 probe. The fitness function to be minimized by a PSO approach is defined by the deviation of the measured and calculated cooling curves. The PSO algorithm was parallelized and implemented on a graphics accelerator …


Analyzing Moment Arm Profiles In A Full-Muscle Rat Hindlimb Model, Fletcher Young, Christian Rode, Alexander Hunt, Roger Quinn Jan 2019

Analyzing Moment Arm Profiles In A Full-Muscle Rat Hindlimb Model, Fletcher Young, Christian Rode, Alexander Hunt, Roger Quinn

Mechanical and Materials Engineering Faculty Publications and Presentations

Understanding the kinematics of a hindlimb model is a fundamental aspect of modeling coordinated locomotion. This work describes the development process of a rat hindlimb model that contains a complete muscular system and incorporates physiological walking data to examine realistic muscle movements during a step cycle. Moment arm profiles for selected muscles are analyzed and presented as the first steps to calculating torque generation at hindlimb joints. A technique for calculating muscle moment arms from muscle attachment points in a three-dimensional (3D) space has been established. This model accounts for the configuration of adjacent joints, a critical aspect of biarticular …


Webinar: Modeling Freeway Traffic In A Mixed Environment: Connected And Human-Driven Vehicles, Xianfeng Terry Yang Jan 2019

Webinar: Modeling Freeway Traffic In A Mixed Environment: Connected And Human-Driven Vehicles, Xianfeng Terry Yang

TREC Webinar Series

Although connected vehicles (CVs) will soon go beyond testbeds, CVs and human-driven vehicles (HVs) will co-exist over a long period. Hence, it is critical to consider the interactions between these two types of vehicles in traffic flow modeling. In this study, we aim to develop a macroscopic model to understand how CVs would impact HVs in the traffic stream. Grounded on the second-order traffic flow model, we study the relationships among flow, density, and speed by two sets of formulations for the groups of CVs and HVs, respectively. A set of friction factors, which indicate CVs' impact to HVs, are …