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EAS PhD Proposal Defense by Cory Hoi Understanding fluid dynamics of surfactant replacement therapy for treating preterm infants with respiratory distress syndrome - A computational study

EAS PhD Program (CSE Option/Mechanical Engineering) PhD PROPOSAL DEFENSE by Mr. Cory Hoi Date: January 20, 2021 Time: 1:00 p.m. - 3:00 p.m. Topic: Understanding fluid dynamics of surfactant replacement therapy for treating preterm infants with respiratory distress syndrome - A computational study Zoom Teleconference: https://umassd.zoom.us/j/93637727210?pwd=VjgvWkZyaFRtTml5VG9JcUgxUGpLZz09 Meeting ID: 936 3772 7210 Passcode: 810959 Abstract: We present 3D multiphase flow simulations of liquid surfactant plug transport through physically representative models of infant lung airway trees. Liquid surfactant instillation into the lung is used to treat respiratory distress syndrome (RDS), affecting preterm infants with a pulmonary surfactant insufficiency. The procedure, commonly known as surfactant replacement therapy (SRT), delivers surfactant plugs with the goal of achieving a uniform film distribution. SRTs effectiveness is tied to the successful plug propagation through each branching airway network. Although effective, SRT has a 35% non-response rate. The difficulty is attributed to the complexity of the human lung, which spans multiple length scales, and that, in turn, complicates predicting the fluid flow in successive airway generations based on plug instillation fluid dynamics at the trachea. To better understand plug flow in each airway generation we have investigated single plug instillation in individual airways (straight tubes) and branching Y-shaped tube models. The results led to correlations between the capillary number, plug film deposition, and plug splitting at bifurcating airways. The preliminary results also include investigation of the effects of multi-plug instillation, plug blockages, and plug rupture on the downstream homogeneity of surfactant in 3-generation airway models. The future work of the proposed PhD research includes simulations of surfactant plug transport in 6- and 8-generation airway models with both Newtonian and non-Newtonian surfactants. The ultimate goal of the proposed research is to develop better understanding of the governing fluid dynamics in upper airway generations to improve SRT. Acknowledgment: The research support from the National Science Foundation under CBET Grant No. 1904204 (Fluid Dynamics Program) is gratefully acknowledged. ADVISOR(S): Dr. Mehdi Raessi, Department of Mechanical Engineering (mraessi@umassd.edu, 508-999-8496) COMMITTEE MEMBERS: Dr. Geoffrey Cowles, SMAST/Fisheries Oceanography Dr. Alfa Heryudono, Department of Mathematics Dr. Hangjian Ling, Department of Mechanical Engineering NOTE: All MNE and EAS Students are ENCOURAGED to attend.

EAS Doctoral Proposal Defense Presensation by Ibrahim Abdalfattah

EAS Doctoral Proposal Defense Presentation by by Ibrahim Abdalfattah Date: January 21, 2021 Time: 10:00 a.m. - 12:00 p.m. Topic: Recycled Plastics Modified Asphalt Binders and Mixtures: Performance Characteristics and Environmental Impact Zoom Teleconference: https://umassd.zoom.us/j/94648196799?pwd=SjV1VXpRWTVSWjBNVDJsOVBXRFJxZz09 Meeting ID: 946 4819 6799 Passcode: 931518 Abstract: During the past decade, there has been a rapid growth in global plastic production, however, only a small proportion of plastic waste is recycled and the rest ended up in landfills and oceans. Recently, the US waste plastic became a critical issue and received much attention, especially, the US plastic recycling rate is less than 10% of the total annual plastic waste. Currently, there is a growing interest in the possibility of using recycled plastic in the asphalt industry as an attempt to reduce the amount of plastics that are send to the landfills. Infusing plastic into highways construction may contribute towards better environmental quality and sustainable development, especially, the highway construction industry is one of the largest material consuming industries in the world. On the other hand, there are equal concerns which are expressed over the feasibility of using recycled plastic on the performance of modified asphalt binders and mixtures and the negative environmental impact if toxic pollutants leach out during the pavement service life. The proposed research study aims at evaluating and quantifying the effect of using the recycled polyethylene (RPE) which is the major plastic waste substance as a modifier on the properties of conventional asphalt binders and mixtures. Different sources of RPEs, asphalt binders, virgin aggregates including low- and high- absorptive aggregates will be used in the developing of modified asphalts and mixtures to understand and evaluate the effect of each parameter on the performance of the RPE modified asphalt and mixture. Asphalt binder rheological evaluation testing will include performance grading (PG), multiple stress creep recovery (MSCR), extended BBR, delta Tc (Tc), and Double Edge Notched Tension (DENT). Moreover, the ductility and cracking susceptibility among different binders after extended aging will be characterized. In this research, two laboratory-produced 12.5-mm and 9.5-mm nominal maximum aggregate size (NMAS) Superpave mixes will be designed as control mixtures then a comprehensive study will be conducted to evaluate the laboratory performance of RPE modified asphalt mixtures with regard to permanent deformation, moisture-induced damage, intermediate- and low-temperature cracking. In addition, the environmental impacts of RPE after subjecting mixtures to accelerated weathering conditions will be investigated using the System for Weathering Infrastructure Materials (SWIM). The SWIM is a custom designed device that exposes infrastructure materials to extended periods of UV aging (radiation & heat from UV exposure), as well as periods of intermittent moisture (rain). Furthermore, the impact of different RPEs on in-situ rutting and bottom-up fatigue cracking performance will be analyzed by the AASHTOWare Pavement ME Design software based on level 1 inputs. The predicted performance curves and pavement preservation and rehabilitation strategies will be used to conduct Life Cycle Cost Analysis (LCCA) to evaluate the overall life-cycle cost of pavements utilizing RPE. ADVISOR(S): Dr. Walaa Mogawer, Department of Civil & Environmental Engineering (wmogawer@umassd.edu, 508-910-9824) COMMITTEE MEMBERS: Prof. Ramon Bonaqist, P.E. Prof. Eyad Masad, P.E., F.ASCE Dr. Tracie Ferreira, Department of Bioengineering Dr. Alireza Asadpoure, Department of Civil & Environmental Engineering NOTE: All EAS Students are ENCOURAGED to attend.

Mechanical Engineering MS Thesis Defense by Mr. David Markt Jr.

Mechanical Engineering MS Thesis Defense by Mr. David Markt Jr. DATE: January 22, 2021 TIME: 11:00 a.m. to 1:00 p.m. LOCATION: Virtual; Zoom link: https://umassd.zoom.us/j/98690657717?pwd=dVNMOGZQVlFXWlZKNjh5eG91Rnd6QT09 Meeting ID: 986 9065 7717 Passcode: 797661 TOPIC: IMPINGEMENT OF HYDROCARBON FUEL DROP TRAINS: DEVELOPMENT OF AN ENHANCED SPRAY-WALL INTERACTION SUBMODEL ABSTRACT: This work investigates surface impingement of mono-dispersed trains of hydrocarbon fuels using computational simulations. The three-dimensional simulations include ethanol and diesel drop impingement onto initially dry and wetted stainless steel substrates. The high-speed micron-sized diesel drop size and impact velocity are representative of fuel injection conditions in internal combustion engines (ICEs). The drop trains serve as a simplified representation of fuel spray. The impingement frequency at which drop trains transition from depositing to splashing was identified. Furthermore, effects of impingement frequency on splashed mass were quantified. Additionally, the effects of a pre-existing film on splashing dynamics were investigated at various film thicknesses, where the temporal evolution of splashed mass was obtained. Secondary droplet characterization was performed on simulation results using a robust algorithm that scrutinizes the volume fraction and velocity fields. This analysis provides insights into the stages of secondary droplet formation. Instantaneous and time-averaged distributions of secondary droplet size, velocity magnitude and trajectory angle are reported. The splashed mass ratio and secondary droplet characterization results were compared to commonly used spray-wall interaction (SWI) sub-models, which are heavily relied upon in a Lagrangian-Eulerian (LE) fuel injection modeling framework. The comparison reveals the SWI sub-models suffer from significant inaccuracy under engine-relevant conditions. Finally, a new SWI sub-model is proposed for diesel fuel injection based on the simulation results. The model provides correlations for splashed mass ratio and secondary droplet size and velocity as a function of a nondimensional velocity. To the best of the author's knowledge, the proposed model is the first SWI sub-model based on engine-relevant drop impingements, which is expected to improve the accuracy of LE combustion simulations. ADVISOR: Dr. Mehdi Raessi, Associate Professor of Mechanical Engineering, College of Engineering, UMassD COMMITTEE MEMBERS: -Dr. Alex Fowler, Professor of Mechanical Engineering, UMassD -Dr. Banafsheh Seyedaghazadeh, Assistant Professor of Mechanical Engineering, College of Engineering, UMassD Open to the public. All MNE students are encouraged to attend. For more information, please contact Dr. Mehdi Raessi (mraessi@umassd.edu, 508-999-8496). Thank you, Sue Cunha, Administrative Assistant UMass Dartmouth Mechanical Engineering Department scunha@umassd.edu 508-999-8492

ECE Oral Comprehensive Exam for Doctoral Candidacy By: Chinmay Mahabal

Topic: 5g Based V2v Communication for Autonomous Vehicles Zoom Teleconference: https://umassd.zoom.com.cn/j/96327292542 Abstract: The autonomous vehicles are equipped with high definition cameras, Lidars and ultrasonic sensors which require a throughput more than 7 Gbps. The existing 4G LTE is challenged to satisfy these requirements hence the current research is focused on 5G using millimeter waves. The URLLC scheme under 5G is specifically designed for such high reliable low latency communications. This standard assumes channel qualities with a latency less than 0.1 millisecond and a reliability greater than 99.99%. One of the key challenges is the lack of any strong standard due to variability in channel state estimation parameters such high frequencies under 5G. My study includes analyzing the characteristics of mmWaves by observing changes in pathloss and SNR with distance between the transreceiver. The dynamic nature of the environment causes high interference and drops the Signal to Noise ratio below the acceptable thresholds. A detailed analysis of the 5G architecture is necessary to increase the flexibility in the end-to-end simulation. An overview of inter-related parameters stretched across all the layers of this architecture is studied and the PHY-MAC level communication is simulated using Matlab. By performing extensive literature survey and simulations a platform for Vehicular communication designed for platooning or convoying is proposed as a test bench. This study includes an end-to-end analysis of the existing challenges, their probable solutions and a comparison between them. The future research directions would include Deep Learning to predict the nonstationary environment parameters and neighboring vehicles for more efficient collective communication, hardware verification of the results on SDRs and special case study for vehicle platooning applications. NOTE: All ECE Graduate Students are ENCOURAGED to attend. All interested parties are invited to attend. Open to the public. Co-Advisors: Dr. Honggang Wang and Dr. Hua Fang Committee Member: Dr. Ruolin Zhou, Department of Electrical & Computer Engineering, University of Massachusetts Dartmouth; Dr. Qing Yang, Department of Computer Science and Engineering, University of North Texas *For further information, please contact Dr. Honggang Wang via email at hwang1@umassd.edu.

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Presidents' Day Holiday: no classes

Presidents' Day holiday, no classes today.

Follow Monday's class schedule

Follow Monday's schedule.

Spring recess begins (after last class or lab)

Spring recess begins today after last class or lab. NOTE: Please consult the PCE calendar if you are taking courses through Professional and Continuing Education.

Spring recess begins after last class (Online & Continuing Education)

Spring recess begins today after last class or lab. NOTE: Please consult the Online & Continuing Education calendar if you are taking courses through Professional and Continuing Education.

Classes resume

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Registration for Fall 2021 begins

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