Mechanical Engineering Commons^™

Agonabadietal_2018_Eduexoemgdelaytutorial_13.Pdf, Arash Mohammadzadeh Gonabadi, Philippe Malcolm

Philippe Malcolm

No abstract provided.

Application Of Pca To Cardiac Optical Mapping, Louis Woodhams

Louis Woodhams

Estimation Of The Centre Of Mass From Motion Capture And Force Plate Recordings: A Study On The Elderly, Sebastien Cotton, Michele Vanoncini, Philippe Fraisse, Nacim Ramdani, Emel Demircan, Andrew P. Murray, Thierry Keller

Andrew P. Murray

The estimation of the centre of mass position in humans is usually based on biomechanical models developed from anthropometric tables. This method can potentially introduce errors in studies involving elderly people, since the ageing process is typically associated with a modification of the distribution of the body mass. In this paper, an alternative technique is proposed, and evaluated with an experimental study on 9 elderly volunteers. The technique is based on a virtual chain, identified from experimental data and locating the subject's centre of mass. Its configuration defines the location of the centre of mass, and is a function of …

Three-Dimensional Confocal Microscopy Indentation Method For Hydrogel Elasticity Measurement, Donghee Lee, Md Mahmudur Rahman, You Zhou, Sangjin Ryu

Md Mahmudur Rahman

No abstract provided.

Cerebrospinal Fluid Dynamics In The Cervical Spine: Importance Of Fine Anatomical Structures, S. Pahlavian, T. Yiallourou, R. Tubbs, A. Bunck, M. Goodin, Francis Loth, M. Raisee, Bryn Martin

Dr. Bryn Martin

No abstract provided.

Novel Sensor For Measuring Sodium Concentration For Dialysis Applications, L. Furby, Ajay Mahajan, Jarlen Don, Bradley Schwartz

Dr. Ajay Mahajan

One of the critical medical problems facing society today is the growing number of patients diagnosed with End-Stage Renal Disease (ESRD). Patients diagnosed with ESRD often face a problem of limited organ transplantation possibilities and time consuming, cumbersome as well as painstaking treatments that affect patients’ quality of life. This study is part of a larger effort to develop new types of dialysis treatments focused on improving the quality of life of ESRD patients. The focus of this paper is the development of a simple, yet reliable sensor that can measure the toxic ion levels in the human …

Full-Field Vibrometry By High-Speed Digital Holography For Middle-Ear Mechanics, Ivo Dobrev

Ivo Dobrev

Hearing loss affects approximately 1 in 10 people in the world and this percentage is increasing every year. Some of the most common courses for hearing loss are disorders of the human tympanic membrane (TM or eardrum) and middle-ear. Early detection and diagnosis of hearing loss as well as research and understanding of the hearing process depend on medical and research tools for quantification of the hearing capabilities, including the function of the human TM in the complex acoustic-mechanical transformation of environmental sounds into vibrations of the middle- and the inner-ear. Current ear exams are assessing the state of the …

Application Of Limited Mixing In The Hele-Shaw Geometry In Fabrication Of Janus Hydrogels, Md Mahmudur Rahman

Md Mahmudur Rahman

It is widely accepted that cells behave differently responding to the stiffness of their extracellular matrix (ECM). Such observations were made by culturing cells on hydrogel substrates of tunable stiffness. However, it was recently proposed that cells may sense how strongly they are tethered to ECM, not the local stiffness of ECM. To investigate both hypotheses, we developed a method to fabricate Janus polyacrylamide (PAAM) gels. We squeeze two drops of different concentrations in the Hele-Shaw geometry to generate radial Stokes flow. When the drops coalesce, limited mixing occurs at the interface due to the narrow confinement, and diffusion normal …

Pre-Impact Lower Extremity Posture And Brake Pedal Force Predict Foot And Ankle Forces During An Automobile Collision, Elizabeth C. Hardin, Anne Su, Antonie J. Van Den Bogert

Anne Su Ph.D.

Background: The purpose of this study was to determine how a driver’s foot and ankle forces during a frontal vehicle collision depend on initial lower extremity posture and brake pedal force. Method of Approach: A 2D musculoskeletal model with seven segments and six right-side muscle groups was used. A simulation of a three-second braking task found 3647 sets of muscle activation levels that resulted in stable braking postures with realistic pedal force. These activation patterns were then used in impact simulations where vehicle deceleration was applied and driver movements and foot and ankle forces were simulated. Peak rearfoot ground reaction …

A Weighted Least-Squares Method For Inverse Dynamic Analysis, Antonie Van Den Bogert, Anne Su

Anne Su Ph.D.

Internal forces in the human body can be estimated from measured movements and external forces using inverse dynamic analysis. Here we present a general method of analysis which makes optimal use of all available data, and allows the use of inverse dynamic analysis in cases where external force data is incomplete. The method was evaluated for the analysis of running on a partially instrumented treadmill. It was found that results correlate well with those of a conventional analysis where all external forces are known.

Development And Validation Of A 3-D Model To Predict Knee Joint Loading During Dynamic Movement, Scott G. Mclean, Anne Su, Antonie J. Van Den Bogert

Anne Su Ph.D.

The purpose of this study was to develop a subject-specific 3-D model of the lowerextremity to predict neuromuscular control effects on 3-D knee joint loading during movements that can potentially cause injury to the anterior cruciate ligament (ACL) in the knee. The simulation consisted of a forward dynamic 3-D musculoskeletal model of the lower extremity, scaled to represent a specific subject. Inputs of the model were the initial position and velocity of the skeletal elements, and the muscle stimulation patterns. Outputs of the model were movement and ground reaction forces, as well as resultant 3-D forces and moments acting across …

Horses Damp The Spring In Their Step, Alan Wilson, M. Mcguigan, Anne Su, Antonie Van Den Bogert

Anne Su Ph.D.

The muscular work of galloping in horses is halved by storing and returning elastic strain energy in spring-like muscle–tendon units1, 2.These make the legs act like a child's pogo stick that is tuned to stretch and recoil at 2.5 strides per second. This mechanism is optimized by unique musculoskeletal adaptations: the digital flexor muscles have extremely short fibres and significant passive properties, whereas the tendons are very long and span several joints3, 4. Length change occurs by a stretching of the spring-like digital flexor tendons rather than through energetically expensive length changes in the muscle5. Despite being apparently redundant for …

Foot And Ankle Forces During An Automobile Collision: The Influence Of Muscles, Elizabeth Hardin, Anne Su, Antonie Van Den Bogert

Anne Su Ph.D.

Muscles have a potentially important effect on lower extremity injuries during an automobile collision. Computational modeling can be a powerful tool to predict these effects and develop protective interventions. Our purpose was to determine how muscles influence peak foot and ankle forces during an automobile collision. A 2-D bilateral musculoskeletal model was constructed with seven segments. Six muscle groups were included in the right lower extremity, each represented by a Hill muscle model. Vehicle deceleration data were applied as input and the resulting movements were simulated. Three models were evaluated: no muscles (NM), minimal muscle activation at a brake pedal …

Sagittal Plane Biomechanics Cannot Injure The Acl During Sidestep Cutting, Scott G. Mclean, Xuemei Huang, Anne Su, Antonie J. Van Den Bogert

Anne Su Ph.D.

Background. Knee joint sagittal plane forces are a proposed mechanism of anterior cruciate ligament injury during sport movements such as sidestep cutting. Ligament force magnitudes for these movements however, remain unknown. The need to examine injury-causing events suggests elucidation via model-based investigations is possible. Using this approach, the current study determined whether sagittal plane knee loading during sidestep cutting could in isolation injure the anterior cruciate ligament. Methods. Experiments were performed on subject-specific forward dynamic musculoskeletal models, generated from data obtained from 10 male and 10 female athletes. Models were optimized to simulate subject-specific cutting movements. Random perturbations (n=5000) were …

Stress And Strain Adaptation In Load-Dependent Remodeling Of The Embryonic Left Ventricle, Christine Buffinton

Christine M Buffinton

Altered pressure in the developing left ventricle (LV) results in altered morphology and tissue material properties. Mechanical stress and strain may play a role in the regulating process. This study showed that confocal microscopy, three-dimensional reconstruction, and finite element analysis can provide a detailed model of stress and strain in the trabeculated embryonic heart. The method was used to test the hypothesis that end-diastolic strains are normalized after altered loading of the LV during the stages of trabecular compaction and chamber formation. Stage-29 chick LVs subjected to pressure overload and underload at stage 21 were reconstructed with full trabecular morphology …

Opportunities For Energy Crop Production Based On Subfield Scale Distribution Of Profitability, Ian J. Bonner, Kara G. Cafferty, David J. Muth, Mark D. Tomer, David E. James, Sarah A. Porter, Douglas L. Karlen

Douglas L Karlen

Incorporation of dedicated herbaceous energy crops into row crop landscapes is a promising means to supply an expanding biofuel industry while benefiting soil and water quality and increasing biodiversity. Despite these positive traits, energy crops remain largely unaccepted due to concerns over their practicality and cost of implementation. This paper presents a case study for Hardin County, Iowa, to demonstrate how subfield decision making can be used to target candidate areas for conversion to energy crop production. Estimates of variability in row crop production at a subfield level are used to model the economic performance of corn (Zea mays L.) …

تمرين سري اول, Dr Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.

Landscape Management For Sustainable Supplies Of Bioenergy Feedstock And Enhanced Soil Quality, Douglas L. Karlen, David J. Muth Jr.

Douglas L Karlen

Agriculture can simultaneously address global food, feed, fi ber, and energy challenges provided our soil, water, and air resources are not compromised in doing so. As we embark on the 19th Triennial Conference of the International Soil and Tillage Research Organization (ISTRO), I am pleased to proclaim that our members are well poised to lead these endeavors because of our comprehensive understanding of soil, water, agricultural and bio-systems engineering processes. The concept of landscape management, as an approach for integrating multiple bioenergy feedstock sources, including biomass residuals, into current crop production systems, is used as the focal point to show …

الگو و دستورالعمل تهيه و تنظيم پايان نامه کارشناسي, Dr Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.

Thermal Modelling For Laser Treatment Of Port Wine Stains, Dong Li, Guo-Xiang Wang, Yaling He

Dr. Guo-Xiang Wang

No abstract provided.

Bioheat Transfer, Alireza Zolfaghari, Mehdi Maerefat

Dr Alireza Zolfaghari

No abstract provided.

7 - استفاده از روش معکوس برای طراحی حرارتی يک اتاق مسکونی، به منظور ايجاد شرايط آسايش حرارتی, Reza Imani, Mehdi Maerefat, Farshad Kowsari, Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.

7 - تأثير نوع پوشش محوطه اطراف ساختمان بر مصرف سالانه انرژي, Alireza Zolfaghari, Mehdi Maerefat

Dr Alireza Zolfaghari

No abstract provided.

Mechanochemical Mechanism For Fast Reaction Of Metastable Intermolecular Composites Based On Dispersion Of Liquid Metal, Valery I. Levitas, Blaine W. Asay, Steven F. Son, Michelle Pantoya

Steven F. Son

An unexpected mechanism for fast reaction of Alnanoparticles covered by a thin oxide shell during fast heating is proposed and justified theoretically and experimentally. For nanoparticles, the melting of Al occurs before the oxide fracture. The volume change due to melting induces pressures of 1–2 GPa and causes dynamic spallation of the shell. The unbalanced pressure between the Al core and the exposed surface creates an unloading wave with high tensile pressures resulting in dispersion of atomic scale liquid Al clusters. These clusters fly at high velocity and their reaction is not limited by diffusion (this is the opposite of …

Heat And Mass Transfer (Kreith), Dr Alireza Zolfaghari

Dr Alireza Zolfaghari

No abstract provided.