bluuebunny/crossref_metadata_2025_split huggingface dataset:
Devices to Aid Mobility: Biomedical Engineering-Focused Undergraduate Senior Capstone Design Projects
Authors: Thompson Lara A. , Xu Jiajun , Shetty Devdas 
Published: January 2019

In order to meet the increasing societal and market demand for a diverse and well-trained Biomedical Engineering (BME) workforce, the University of the District of Columbia (UDC), the nation’s only urban land-grant institution, the District of Columbia’s only public institution of higher education, and a historically black college and university (HBCU), nurtures BME activities focused on exposure, training and cultivation through research and experiential learning. Undergraduate design projects and research-based learning opportunities in BME are key program ingredients. This paper presents the former (i.e., three, BME-related undergraduate senior Capstone Design projects that target devices to aid patient immobility) namely, the design of: 1) an ankle foot orthosis, 2) an upperlimb robotic hand prosthetic, and 3) a chairless chair lower limb exoskeleton.
A current focus of the UDC BME program is Rehabilitation Engineering (i.e., interventions and devices aimed at aiding those with mobility impairments). We briefly discuss the necessity for rehabilitation-focused, biomedical-related undergraduate experiences and training for underrepresented minority students at UDC, in particular, undergraduate engineering education through multidisciplinary BME projects that foster hands-on creativity towards innovative designs.
In addition to critical design experiences and undergraduate training in BME, devices may have the potential to develop into new commercial technologies and/or research projects that will aid and enhance the quality life of individuals suffering from a wide-range of mobility-related issues.
Development of a Low Cost Self-Sustaining Water Distillation System Using Activated Carbon Nanofluids
Authors: Mishra Ashreet , Nnanna A. G. Agwu 
Published: January 2019

There is an ever increasing need to provide clean and portable drinking water in developing countries because of the poor quality of water, which causes various water borne diseases killing millions of infants and elderly people every year. There have been a lot of recent developments in the field of solar enabled water distillation where pure water is being generated. But a majority of the system use some type of external energy source for the system to run on which might make it efficient but can cause dependence on energy sources. The power of the Sun can be effectively harnessed and used as heat and light source for efficient steam generation. One of the challenges is to develop a low cost system which can perform at par with the best and extravagant systems.
This paper investigates the performance of the solar distillation system when activated carbon nanoparticles are used along with brine and other sources of impure water so as to obtain clean water. The activated carbon nanoparticle which are an efficient and cheap mode of water purification enhanced the productivity of the system by 190% when compared to saline water due to its steam generation properties. A solar simulator of 1KWm2 was used to simulate the sun. Various parameters like the variation of air flow on condensation rate, height of fluid on vapor production rate and the temperature variation of the system are evaluated. Parametric studies of the effect of water quality and salinity were performed. It was determined that the optimum output rate of distilled water was 240 grams (6000gday.m2) was determined by the system from the parametric studies and the system is feasible and cost effective to be used in real world application. All of these standout features make the system a low cost option which can tackle the clean water dilemma in developing countries.
EHSA Primary Flight Controls Seals Wear Degradation Model
Authors: Bertolino Antonio C. , Gentile Rocco , Jacazio Giovanni , Marino Francesco , Sorli Massimo 
Published: January 2019

Seals are widely used in hydraulic power systems to prevent fluid leakages. However, several types of degradation can decrease the performance of these components such as wear, which induces changes in the geometry of the cross-section area, influencing their sealing capability. Over the years, their behaviour has been primarily investigated with several theoretical and experimental researches. All these valuable results can be considered as a starting point for further investigations on the interaction between seals and the complete hydraulic equipment and on the root of seals degradation.
This article proposes a physical model of performance degradation acting on dynamic seals of an electro-hydraulic servo-actuator (EHSA) ram for primary flight controls. In this article, a dynamic non-linear seals degradation model has been developed, based on the Hart-Smith hyperelasticity model, which physically describes the stress and strain of “rubber-like” materials. Similarly, wearing has been assessment by using the Archard’s equation. Furthermore, different operating temperatures have been considered to analyze the effect on seals performances.
The integration between the mentioned seals degradation model and the high-fidelity model of the complete EHSA allows to evaluate the influence of various wear levels on the actuator behaviour. This research activity is inserted into a more extensive project of Prognostic and Health Management (PHM) of EHSAs. The results of the proposed simulations reveal how the performance of an EHSA can be affected by seals degradations.
Problem Based Learning: Generating a 3D Educational Brain Model to Engage Undergraduate Engineering Honors Students
Authors: Gomez Connie , Nasir Sheema 
Published: January 2019

Engineering courses offered through the Honors Program allow students to conduct both research and design during their time at a community college, which is extremely valuable due to the limited number of research opportunities when compared to a four-year institution. Additionally, community college engineering courses normally serve students seeking to enter a wide range of engineering disciplines.
Therefore, any research or design experience with lasting impact must also encompass a wide range of topics while also fostering communication, teamwork, creativity and life-long learning. This paper describes an engineering graphics honors course that engaged students in the development of a CAD model and prototype of a 3D brain model for use by Anatomy and Physiology students. This project allowed students to engage in the areas of personalized learning, reverse engineering the brain, manufacturing as well a computer-aided design. This paper discusses the development of technical and soft skill competencies through student performance and student perception via questionnaires. Finally, this paper sets forth recommendations for other community colleges interested in developing problem-based learning opportunities throughout their engineering curriculum.
Numerical Study on Influencing Factors of Film Cooling on Turbine Blade Leading Edge Under Rotating State
Authors: Ma Yiwen , Li Haiwang , Yang Meisong , Wu Min , Zhou Huimin 
Published: January 2019

Engine turbine blades operate at a high speed of rotation and are subjected to high temperature and pressure prevailing gas from the combustion chamber, making the working condition very harsh. In particular, the leading edge of the blade, which is directly subjected to high-temperature gas impacts, is the hottest part of the turbine. Therefore, it is of great importance to improve the protection of the blade leading edge and enhance the understanding of this part of the flow field and temperature field. This paper will focus on the phenomenon of wake deflection and study the film cooling characteristics of the turbine blade under rotating condition. The characteristics of pressure surface and suction surface of the blade are verified by numerical simulation. The contents cover the influence of the film hole diameter, pitch, blowing ratio, rotation number and the development process, the film cooling efficiency on the outflow of coolant film. The result shows that Coriolis force, centrifugal force and secondary flow induced by rotation will change the mainstream flow along the blade, which will lead to changes of pattern concerning the development of the film on the blade surface. In the process of wake development, deflection occurs in different directions at different positions, and the greater the rotation number is, the more obvious the degree of deflection will be.
Studying the model with film holes on the leading edge of the blade, these phenomena can be observed along the downstream on the pressure and suction surfaces. Also, models with film holes independently set on the pressure and suction surfaces can be used as proof of these features. At the same time, this paper studies the flow and heat transfer characteristics of the leading-edge gas film under rotating condition and focuses on the influence of rotation on the outflow and the development processes of the wake. The gas film cooling models in rotating state of different film hole diameters and film hole radial spacing will also be compared to further understand the flow and heat transfer characteristics of film cooling on the leading edge of the blade.
A Numerical Approach for the Evaluation of the Energy Efficiency in Ventilated Façade
Authors: Milani Massimo , Montorsi Luca , Venturelli Matteo 
Published: January 2019

The paper studies the ventilated façade as a potential alternative to conventional coating technologies for the thermal insulation of building’s external walls. The ventilated façade is modeled by means of a CFD approach that accounts for the full 3D-geometry of the building, the walls thickness and materials’ thermal properties. The effects of the windows on the heat losses and in the performance of the ventilated façade are modeled in order to accurately characterize the thermal behavior of the system. The solar radiative heat transfer during two representative days of the year is considered in the analysis and a multiband thermal radiation is adopted to capture the different nature of radiative heat exchange according to the light wavelengths.
The numerical approach enables to estimate the thermo-fluid dynamic behavior of the system and the temperature distribution and the velocity flow field within the air gap between the walls are addressed and their influence on the heat transfer through the building’s external walls is determined. The CFD analysis is employed to compare different configurations of the ventilated façade for improving the thermal insulation of the building; the performance of each scenario is determined in terms of electric energy and fuel consumption for the air conditioning and the heating system. Thus, the potential saving of the energy cost for ambient thermal conditioning is evaluated.
The analysis investigates the effects on the energy efficiency of different geometrical features of the system such as the height of the building and the air gap thickness and theoretical correlations are derived in order to estimate the best tradeoff between the energy efficiency of the building and the investment of the ventilated façade configuration.
Finite Element Analysis (FEA) for Optimization the Design of a Baja SAE Chassis
Authors: Maradey Lázaro Jessica Gissella , Esteban Villegas Helio Sneyder , Blanco Caballero Braulio José 
Published: January 2019

The chassis is one of the main components of the vehicle, which provides not only support and stiffness but also gives the vehicle its shape. Its design is a challenge for the mechanical engineer: to achieve an optimum resistance-weight ratio which can ensure the safety of the pilot. To optimize its design, engineers can rely on the Finite Element Analysis (FEA) an ideal method to predict the behavior of the chassis to the different loads (Mechanical Effort, fatigue, movement) and effects (Vibration, heat, fluid flow, transfer of heat) given in real environments. This analysis is able to describe if a product may break, wear out or, otherwise, it will work as expected. Additionally, it allows the variation of the geometry and materials used so that the most suitable one can be selected for the application in study.
This article aims to show the preliminary design of the chassis (Simplified 3D model using CAD) taking into account the rules of the SAE competition and its optimization by using the FEA analysis and also taking into account its geometry. Static load analysis will start by selecting the appropriate mesh size and having as criteria that Von Mises stress should be less than the yield point of the selected material. Likewise, the deformation of the members that make up the chassis should not put at risk the safety of the pilot. Moreover, a Modal Analysis of the chassis to verify the natural frequencies and vibration modes is also made.
The result of this research provides a design approach for the validation (theory vs simulation) and optimization of the chassis to ensure better performance as well as to facilitate the manufacture of its parts and assembly.
Hands-On Experiences for Problem Solving in Engineering Education Based on Trees and Plants
Authors: Vargas-Silva Gustavo , Jawaharlal Mariappan 
Published: January 2019

We teachers know that problem solving is a crucial skill for our students. It is indispensable for developing original and creative thinking. We also know that deep learning of engineering fact can be assisted by using non-conventional tools and heterodox ideas for teaching, learning and presenting technical concepts. On that sense, we propose that engineering students could learn how to solve hands-on problems from nature; in particular from the plant kingdom.
In addition, we engineers should not turn our back to nature. We should start a new voyage of discovery, seeking new landscapes with a different outlook. But how? The present paper presents an approach to integrate trees and plants into engineering education to learn problem solving hands-on experiences. The aim of this approach is to teach engineering design using trees in the local area with an emphasis on structural strategies. Students taking courses such as statics, dynamics, strength of materials, stress analysis, material science, and design courses can benefit tremendously from studying trees. Furthermore, this approach provides an exciting opportunity for students to understand the complexities of real world living systems, appreciate the genius of nature’s design, and develop methods to create sustainable designs.
We think that those kind of natural realistic problems are complex: they have conflicting objectives, multiple solution methods, non-engineering success criteria, non-engineering constraints, unanticipated issues, interactions, collaborative activity systems, and multiple forms of problem representation. From an educational point of view, using a tree can bring tremendous practical benefits for problem solving in engineering education. Trees are everywhere, and they can easily integrate them into the classroom. Trees offer unlimited potential for teaching and research. For example, each student will have a different tree, and there are plenty of them, so each problem will be original and creative for each student providing a genuine learning experience.
The present work puts on view a new development for teaching structural mechanics based on plant biomechanics, i.e. the study of the structural strategies of plants (and trees). The goal is to understand and emulate structures and functions of the plant kingdom to develop structural solutions in engineering. Therefore this paper presents teaching results and novel concepts for problem solving in engineering education, seeking new landscapes.
Gait Analysis for Muscular Forces Evaluation in Human Movement: Integration Protocol of Typical Measurement Methods
Authors: Fontanili Luca , Milani Massimo , Montorsi Luca , Valente Giordano 
Published: January 2019

The paper focuses on the gait analysis for the investigation of the typical events occurring in human movements and validate its use as a method for musculoskeletal disease evaluation and for the improvement of athletic training. In the present research the motion capture system is combined with an in-house developed prototype of uniaxial force plates for the measurement of the vertical component of ground reaction forces during movement.
While similar techniques are implemented for gait, this equipment can be employed to investigate running, thus, covering a larger number of possible applications and providing a deeper insight either of the athlete performance or the disease analysis.
For the prevention and the treatment of those events occurring during running, a thorough understanding of its mechanisms is critical; therefore, a method for evaluating both the kinematic behavior of the human body and the ground reaction forces combined to a model for determining the muscle forces is proposed.
An infrared motion capture technique is adopted for measuring accurately the body motion and a multiple force-plate system is used to calculate the force exerted by the ground and sub-divided in the three components by an ad-hoc developed routine.
Moreover, the data are used as input parameters for the OpenSim software to derive muscles forces. Finally, the potential of the proposed protocol is determined by an experimental campaign on healthy subjects and a significant database of muscle forces is constructed for different running speeds.
Reconstruction of Swirling Blood Flow in the Heart and Aorta on the Basis of Measurements of Dynamic Geometry and Elastic Properties of the Flow Channel
Authors: Talygin Eugeny A. , Zhorzholiani Shota T. , Tkhagapsova Marina M. , Tsygankov Yuriy M. , Agafonov Andrei V. , Gorodkov Alexander Y. , Kiknadze Gennadiy I. , Bockeria Leo A. 
Published: January 2019

As it has been shown previously, the blood flow in the heart and the main vessels is a self-organizing tornado-like flow of a viscous fluid, exhaustively described by the particular solution of nonstationary hydrodynamic equations coined in 1986. This solution is implemented in a local dynamic cylindrical coordinate system, which origin moves with the flow. Streamlines of these flows are characterized with an axial symmetry and determine certain restrictions to the geometry of the flow channels. It has been proved, that the experimentally measured orientations of intraventricular trabeculae and dynamic geometric characteristics of the aortic flow channel during the cardiac cycle satisfy the conditions for the self-organization of tornado-like blood flow. This enables to obtain relative estimates of the flow parameters using the geometric characteristics of the flow channel. For this, a set of experimentally measured quasi-invariant anatomical marks was used, which static and dynamic parameters are utterly determined by the structure of the dominant blood jet. Such marks are the position of the embouchures of pulmonary veins and the left atrium auricle, the directions of the trabecular profile on the left ventricle streamlined surface, the dynamic geometry of the mitral and aortic valves, the length and radial elasticity of the aorta, etc. These marks allow a formal localization of the dynamic coordinate system position of a swirling blood flow in the investigated part of the cardiovascular channel and more accurate estimation of the jet structural parameters evolution.
Basing on these parameters, a consistent theory of the initiation and evolution of swirling blood jet in the flow channel beginning from the left atrium to the aorta and its main branches has been proposed. The result of the study is a concept, integrating the measured characteristics of the heart and the aorta flow channel (dynamic dimensions, elasticity) and the structural parameters of swirling blood flow. It was shown that flow channel pathological changes significantly affect the flow structure.
Fluid-Structure Interaction of Blood Flow in Human Aorta Under Dynamic Conditions: A Numerical Approach
Authors: Martelli Francesca , Milani Massimo , Montorsi Luca , Ligabue Guido , Torricelli Pietro 
Published: January 2019

The paper proposes a numerical approach for the analysis of the blood flow in human aorta under real operating conditions. An ad-hoc procedure is developed for importing the aorta geometry from magnetic resonance imaging in order to have a patient based analysis. The aortic flow is simulated accounting for the dynamic behavior of the flow resulting from the heart pulse and for the non-Newtonian properties of blood. Fluid – structure analysis is carried out to address the mutual influence of the flow transient nature and the aorta walls’ deformation on the pressure flow field and tissue’s stresses. Finite element method approach is used for the structural analysis of the aorta walls which are assumed as a linear elastic isotropic material; nevertheless, different regions are introduced to account for the Young modulus variation from the ascending aorta to the common iliac arteries. Mesh morphing techniques are adopted to simulate the wall deformation and a two equation turbulence model is adopted to include the turbulence effects.
The proposed numerical approach is validated against the measurements carried out on magnetic resonance imaging scanner and a good agreement is found in terms of aorta wall maximum and minimum deformation during the cardiac cycle. Therefore, the fluid-structure analysis can provide an important tool to extend the insight of the aortic system from magnetic resonance imaging techniques and improve the understanding of arteriosclerosis and the related phenomena as well as their dependence on flow structure and tissue stresses.
Computational Investigation of Flow Over Geometry Compliant Lattice Structures
Authors: Tinsley James J. , Vernon Gregory J. , Homan Kelly O. 
Published: January 2019

With the increasing prevalence of additive manufacturing, geometries that would not have been possible to manufacture just a few years ago are becoming a reality. One example is the ability to create pipes with integral, geometry compliant lattice structures. These compliant lattice structures offer the potential to greatly enhance heat transfer in arbitrary flow passages. This preliminary paper will focus on the development of an isothermal simulation model in OpenFOAM, to model the nature of the flow for a single unit cell, a unit cell screen, and a series of unit cell screens.
Honeywell FM&T is a contractor of the U.S. Government under Contract No. DE-NA0002839.