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Articles 1411 - 1440 of 2631
Full-Text Articles in Engineering
Applications Of Open Source Gmaw-Based Metal 3-D Printing, Yuenyong Nilsiam, Paul G. Sanders, Joshua M. Pearce
Applications Of Open Source Gmaw-Based Metal 3-D Printing, Yuenyong Nilsiam, Paul G. Sanders, Joshua M. Pearce
Department of Materials Science and Engineering Publications
The metal 3-D printing market is currently dominated by high-end applications, which make it inaccessible for small and medium enterprises, fab labs, and individual makers who are interested in the ability to prototype and additively manufacture final products in metal. Recent progress led to low-cost open-source metal 3-D printers using a gas metal arc welding (GMAW)-based print head. This reduced the cost of metal 3-D printers into the range of desktop prosumer polymer 3-D printers. Consequent research established good material properties of metal 3-D printed parts with readily-available weld filler wire, reusable substrates, thermal and stress properties, toolpath planning, bead-width …
Development Of A Resilient 3-D Printer For Humanitarian Crisis Response, Benjamin L. Savonen, Tobias Mahan, Maxwell W. Curtis, Jared W. Schreier, John K. Greshonen, Joshua M. Pearce
Development Of A Resilient 3-D Printer For Humanitarian Crisis Response, Benjamin L. Savonen, Tobias Mahan, Maxwell W. Curtis, Jared W. Schreier, John K. Greshonen, Joshua M. Pearce
Department of Materials Science and Engineering Publications
Rapid manufacturing using 3-D printing is a potential solution to some of the most pressing issues for humanitarian logistics. In this paper, findings are reported from a study that involved development of a new type of 3-D printer. In particular, a novel 3-D printer that is designed specifically for reliable rapid manufacturing at the sites of humanitarian crises. First, required capabilities are developed with design elements of a humanitarian 3-D printer, which include, (1) fused filament fabrication, (2) open source self-replicating rapid prototyper design, (3) modular, (4) separate frame, (5) protected electronics, (6) on-board computing, (7) flexible power supply, and …
Me-Em Enewsbrief, March 2018, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Me-Em Enewsbrief, March 2018, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Department of Mechanical and Aerospace Engineering eNewsBrief
No abstract provided.
The Suitability Of Zn–1.3% Fe Alloy As A Biodegradable Implant Material, Alon Kafri, Shira Ovadia, Jeremy Goldman, Jaroslaw W. Drelich, Eli Aghion
The Suitability Of Zn–1.3% Fe Alloy As A Biodegradable Implant Material, Alon Kafri, Shira Ovadia, Jeremy Goldman, Jaroslaw W. Drelich, Eli Aghion
Michigan Tech Publications, Part 1
Efforts to develop metallic zinc for biodegradable implants have significantly advanced following an earlier focus on magnesium (Mg) and iron (Fe). Mg and Fe base alloys experience an accelerated corrosion rate and harmful corrosion products, respectively. The corrosion rate of pure Zn, however, may need to be modified from its reported ~20 µm/year penetration rate, depending upon the intended application. The present study aimed at evaluating the possibility of using Fe as a relatively cathodic biocompatible alloying element in zinc that can tune the implant degradation rate via microgalvanic effects. The selected Zn–1.3wt %Fe alloy composition produced by gravity casting …
Research On An Electric Vehicle Owner-Friendly Charging Strategy Using Photovoltaic Generation At Office Sites In Major Chinese Cities, Su Su, Yong Hu, Tiantian Yang, Shidan Wang, Ziqi Liu, Xiangxiang Wei, Koji Yamashita, Et Al.
Research On An Electric Vehicle Owner-Friendly Charging Strategy Using Photovoltaic Generation At Office Sites In Major Chinese Cities, Su Su, Yong Hu, Tiantian Yang, Shidan Wang, Ziqi Liu, Xiangxiang Wei, Koji Yamashita, Et Al.
Michigan Tech Publications, Part 1
Electric vehicles (EV) and photovoltaic (PV) generation are widely recognized around the world. Most EV owners in the major Chinese cities are forced to charge their EV batteries at the workplace during the daytime due to the limited space near their homes, which will increase the peak load during the daytime. On the other hand, the PV output is most likely to have a peak at around noon, which means, PVs could have a potential capability to compensate the EV charging load. An EV owner-friendly charging strategy based on PV utilization which alleviates both the EV charging constraints and the …
Advanced Pavement Materials For Sustainable Transportation Infrastructure, Zhanping You, Meor O. Hamzah, Hainian Wang, Aboelkasim Diab, Qingli Dai
Advanced Pavement Materials For Sustainable Transportation Infrastructure, Zhanping You, Meor O. Hamzah, Hainian Wang, Aboelkasim Diab, Qingli Dai
Michigan Tech Publications, Part 1
Many road managers and stakeholders are looking for more and better options for the construction and maintenance of flexible and rigid pavements. Well-designed strategies for pavement construction and maintenance have attracted the interests of researchers since a large number of existing pavements are facing deterioration all over the world. The selection and engineering properties of paving materials are crucial factors affecting the durability and therefore demanding standards of sustainability of the constructed pavement. Researchers worldwide are putting extensive efforts to develop and promote advanced pavement materials and structures for constructing and maintaining sustainable pavements. Pavement materials that can improve durability, …
No-Releasing Polymers And Uses Thereof, Megan C. Frost, Genevieve Romanowicz
No-Releasing Polymers And Uses Thereof, Megan C. Frost, Genevieve Romanowicz
Michigan Tech Patents
The present invention provides stable, photosensitive polymers that release NO response to intensity and wavelength of light, methods of making such polymers and methods using such polymers.
Evaluation Of Well Designs To Improve Access To Safe And Clean Water In Rural Tanzania, Aminata Kilungo, Linda Powers, Nathan B. Arnold, Kelli Marie Whelan, Kurt Paterson, Dale Young
Evaluation Of Well Designs To Improve Access To Safe And Clean Water In Rural Tanzania, Aminata Kilungo, Linda Powers, Nathan B. Arnold, Kelli Marie Whelan, Kurt Paterson, Dale Young
Michigan Tech Publications, Part 1
The objective of this study was to examine three well designs: drilled wells (20–30 m deep), closed dug wells (>5 m deep), and hand-dug open wells (<5 m deep), to determine the water quality for improving access to safe and clean water in rural communities. Heterotrophic plate count (HPC), total coliforms (TC), Escherichia coli (E. coli) and turbidity, were used to assess the water quality of 97 wells. Additionally, the study looked at the microflora diversity of the water, focusing on potential pathogens using outgrowth, PCR, and genome sequencing for 10 wells. Concentrations of TC for the open dug wells (4 × 104 CFU/100 mL) were higher than the drilled (2 × 103 CFU/100 mL) and closed dug wells (3 × 103 CFU/100 mL). E. coli concentration for drilled and closed dug wells was <22 MPN (most probable number)/100 mL, but higher for open wells (>154 MPN/100 mL). The drilled well turbidity (11 NTU) was within the standard deviation of the closed well (28 NTU) compared to open dug wells (49 NTU). Drilled and closed wells had similar microbial diversity. There were no …22>5>
2017-2018 Che Newsletter, Department Of Chemical Engineering, Michigan Technological University
2017-2018 Che Newsletter, Department Of Chemical Engineering, Michigan Technological University
Department of Chemical Engineering Newsletters
Table of Contents
- Department
- Convocation
- Student News
- Faculty
- Alumni & Friends
2018 Civil And Environmental Engineering Department News, Department Of Civil And Environmental Engineering, Michigan Technological University
2018 Civil And Environmental Engineering Department News, Department Of Civil And Environmental Engineering, Michigan Technological University
Department of Civil, Environmental, and Geospatial Engineering Newsletters
Table of Contents
- External Awards
- Faculty Feature
- Student Features
- Outreach
- Alumni Feature
- CEE Academy
- Internal Awards
- Donors
Me-Em 2017-18 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Me-Em 2017-18 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University
Department of Mechanical and Aerospace Engineering Annual Reports
Table of Contents
- Curriculum Revision
- The Result: MEP I-IV
- ME-EM Research
- Alumni Features
- Enrollment & Degrees
- Graduates
- Faculty & Staff
- Alumni
- Donors
- Contracts & Grants
- Patents & Publications
Mechanistic Insight Into The Degradation Of Nitrosamines Via Aqueous-Phase Uv Photolysis Or A Uv-Based Advanced Oxidation Process: Quantum Mechanical Calculations, Daisuke Minakata, Erica Coscarelli
Mechanistic Insight Into The Degradation Of Nitrosamines Via Aqueous-Phase Uv Photolysis Or A Uv-Based Advanced Oxidation Process: Quantum Mechanical Calculations, Daisuke Minakata, Erica Coscarelli
Department of Civil, Environmental, and Geospatial Engineering Publications
Nitrosamines are a group of carcinogenic chemicals that are present in aquatic environments that result from byproducts of industrial processes and disinfection products. As indirect and direct potable reuse increase, the presence of trace nitrosamines presents challenges to water infrastructures that incorporate effluent from wastewater treatment. Ultraviolet (UV) photolysis or UV-based advanced oxidation processes that produce highly reactive hydroxyl radicals are promising technologies to remove nitrosamines from water. However, complex reaction mechanisms involving radicals limit our understandings of the elementary reaction pathways embedded in the overall reactions identified experimentally. In this study, we perform quantum mechanical calculations to identify the …
Oil Spills Detection By Means Of Uas And Inexpensive Airborne Thermal Sensors, Ausama Al Shammari
Oil Spills Detection By Means Of Uas And Inexpensive Airborne Thermal Sensors, Ausama Al Shammari
Dissertations, Master's Theses and Master's Reports
This thesis provides an overview of oil spill scenarios and the remote sensing methods used for detection and mapping the spills. It also discusses the different kinds of thermal sensors used in oil spills detection. As UAS is becoming an important player in the oil and gas industry for the low operating costs involved, this research involved working with a cheap thermal airborne sensor mounted on DJI Phantom 4 system. Data was collected in two scenarios, first scenario is collecting data in Michigan’s Upper Peninsula at a petroleum company location and the second scenario was an indoor experiment simulating an …
Pyrolysis Of Fiber-Plastic Waste Blends, Shreyas Kolapkar
Pyrolysis Of Fiber-Plastic Waste Blends, Shreyas Kolapkar
Dissertations, Master's Theses and Master's Reports
The main objective of this work is to investigate fast pyrolysis of fiber and plastic feedstocks in order to understand the synergistic effect from their co-pyrolysis. In this on-going work, fiber, plastic and their blend are characterized and pyrolysis oil is produced from them in the fast batch pyrolysis reactor. Based on a heat transfer model it is shown that results of oil produced from batch reactor will be applicable to the continuous paddle reactor. From feedstock characterization, chlorine was observed particularly in the plastic feedstock. Thus, chlorine removal method using torrefaction and high shear mixing was implemented and was …
Anomaly Inference Based On Heterogeneous Data Sources In An Electrical Distribution System, Yachen Tang
Anomaly Inference Based On Heterogeneous Data Sources In An Electrical Distribution System, Yachen Tang
Dissertations, Master's Theses and Master's Reports
Harnessing the heterogeneous data sets would improve system observability. While the current metering infrastructure in distribution network has been utilized for the operational purpose to tackle abnormal events, such as weather-related disturbance, the new normal we face today can be at a greater magnitude. Strengthening the inter-dependencies as well as incorporating new crowd-sourced information can enhance operational aspects such as system reconfigurability under extreme conditions. Such resilience is crucial to the recovery of any catastrophic events. In this dissertation, it is focused on the anomaly of potential foul play within an electrical distribution system, both primary and secondary networks as …
Extending Maneuverability Of Internally Actuated Underwater Gliders, An Attempt To Develop An Open Platform For Research And Education, Saeedeh Ziaeefard
Extending Maneuverability Of Internally Actuated Underwater Gliders, An Attempt To Develop An Open Platform For Research And Education, Saeedeh Ziaeefard
Dissertations, Master's Theses and Master's Reports
Increasing maneuverability of internally actuated Underwater Gliders (UGs) is inevitable due to high demands in underwater surveillance and reconnaissance missions where agility and stealthiness are the keys to success. High maneuverability is needed to provide the opportunity for optimal trajectory planning, planar motion smoothness, and re-planning adapting to the dynamic environments.
This work explores extending the maneuverability of underwater gliders through coupled improvement in mechanical design, efficient use of internal actuation, and motion planning strategy utilizing flight concatenation. The existence of five flight patterns ``advanced flight", inspired by air gliders, enabled solely by utilizing internal actuation are investigated: Circle, Oval …
Modelling And Analysis Of Chevy Volt Gen Ii Hybrid Vehicle In Electric Mode, Kaushik Surresh
Modelling And Analysis Of Chevy Volt Gen Ii Hybrid Vehicle In Electric Mode, Kaushik Surresh
Dissertations, Master's Theses and Master's Reports
The technical report discusses the high fidelity modelling of the powertrain of Chevy Volt Gen II Hybrid Vehicle in the Electric Mode. The overall objective of the powertrain model was to predict total energy consumed within 5% of experimental data for different drive cycles in Charge Depleting Mode. The following powertrain elements were modelled in Matlab and Simulink using parameters and performance maps provided by General Motors: battery, E-Motor, TPIM power electronics, transmission auxiliary pumps and spin losses.
An electric circuit based dynamic model of the Li-ion battery was developed. Static models of the E Motor, TPIM inverter, transmission auxiliary …
Two Pumps, One Volcano: An Epanet Feasbility Study Of Connecting Two Groundwater Pumps In Rural Coastal Communities In West Ambae, Vanuatu, Helen Amiri
Dissertations, Master's Theses and Master's Reports
In situations where groundwater supply shows vulnerability, improving water distribution network resiliency can be desirable. To do so, one water source can be linked with another to provide a redundant source.
On the South Pacific island of Ambae, the water demands of its residents routinely exceeded supply. Residents had traditionally used rainwater collection as their sole water supply source. In 2017, groundwater drilling operations created an alternative water supply at two community institutions, Ndui Ndui Health Center and Londua Junior Secondary School. One borehole went dry during pump testing; the feasibility of linking these two boreholes is investigated herein.
EPANET …
Electro-Mechanical-Thermal Modeling And Stability Of Pulsed Power Loads On A Dc Network, Joshua Allen Dillon
Electro-Mechanical-Thermal Modeling And Stability Of Pulsed Power Loads On A Dc Network, Joshua Allen Dillon
Dissertations, Master's Theses and Master's Reports
Modern military aircraft are developing larger pulsed power loads varying from new weapon technologies to advanced avionics and other electrical equipment. Pulsing power loads emulate a pulse width modulated signal which have non-linear destabilizing effects on the electrical system. Additionally, these devices have thermal properties that can induce electrical stability issues at low and high temperatures and various pulsing load conditions. These non-linear electrical stability issues carry through to the mechanical and thermal systems of the aircraft and can damage components. The MATLAB/Simulink workspace is used to simulate a non-linear model of an aircraft’s electrical-mechanicalthermal (EMT) system. This system includes …
A Model To Predict Concentrations And Uncertainty For Mercury Species In Lakes, Ashley Hendricks
A Model To Predict Concentrations And Uncertainty For Mercury Species In Lakes, Ashley Hendricks
Dissertations, Master's Theses and Master's Reports
To increase understanding of mercury cycling, a seasonal mass balance model was developed to predict mercury concentrations in lakes and fish. Results indicate that seasonality in mercury cycling is significant and is important for a northern latitude lake. Models, when validated, have the potential to be used as an alternative to measurements; models are relatively inexpensive and are not as time intensive. Previously published mercury models have neglected to perform a thorough validation. Model validation allows for regulators to be able to make more informed, confident decisions when using models in water quality management. It is critical to quantify uncertainty; …
Mitigating The Effect Of Misspeculations In Superscalar Processors, Zhaoxiang Jin
Mitigating The Effect Of Misspeculations In Superscalar Processors, Zhaoxiang Jin
Dissertations, Master's Theses and Master's Reports
Modern superscalar processors highly rely on the speculative execution which speculatively executes instructions and then verifies. If the prediction is different from the execution result, a misspeculation recovery is performed. Misspeculation recovery penalties still account for a substantial amount of performance reduction. This work focuses on the techniques to mitigate the effect of recovery penalties and proposes practical mechanisms which are thoroughly implemented and analyzed.
In general, we can divide the misspeculation penalty into four parts: misspeculation detection delay; stale instruction elimination delay; state restoration delay and pipeline fill delay. This dissertation does not consider the detection delay, instead, we …
Meniscus Modeling And Emission Studies Of An Ionic Liquid Ferrofluid Electrospray Source Emitting From A Magneto-Electric Instability, Brandon Jackson
Meniscus Modeling And Emission Studies Of An Ionic Liquid Ferrofluid Electrospray Source Emitting From A Magneto-Electric Instability, Brandon Jackson
Dissertations, Master's Theses and Master's Reports
This dissertation presents three studies on the electrospray of ionic liquid ferrofluid. Ionic liquid ferrofluids are electrically conductive super-paramagnetic fluids which respond strongly in the presence of electric and magnetic fields. When a small reservoir of ionic liquid ferrofluid is positioned within a magnetic field, magnetic stresses will deform the fluid interface into a peak. The addition of a strong electric field will further stress the fluid interface until a threshold stress is reached at which point the surface tension cannot contain the combined stresses and a spray of fluid or ions results at the apex. This process is termed …
A Bayesian Network Approach To Battery Aging In Electric Vehicle Transportation And Grid Integration, Mehdi Jafari
A Bayesian Network Approach To Battery Aging In Electric Vehicle Transportation And Grid Integration, Mehdi Jafari
Dissertations, Master's Theses and Master's Reports
Nowadays, batteries in electric vehicles (EVs) are facing a variety of tasks in their connection to the power grid in addition to the main task, driving. All of these tasks play a very significant role in the battery aging, but they are highly variable due to the change in the driver behavior, grid connection availability and weather conditions. The effect of these external factors in the battery degradation have been studied in literature by mostly deterministic and some stochastic approaches, but limited to specific cases.
In this dissertation, first, a large-scale deterministic approach is implemented to evaluate the effect of …
A Bluetooth Low-Energy Wireless Sensor Platform For Continuous Monitoring Of A Bioreactor Environment During Cell Manufacturing, Brad Nelson
Dissertations, Master's Theses and Master's Reports
A wireless sensor platform based on Bluetooth Low-Energy (BLE) technology was designed and prototyped for continuous monitoring of physical conditions and chemical analytes, which could be applied to bioreactors during the cell manufacturing process. Controlling environmental conditions such as pH, oxygen, glucose, temperature, and pressure is vital to ensure the consistency of the manufactured cells and maintain the potency of the product. Current methods to control bioreactor conditions focus only on monitoring the cell culture environment during cell growth, but there is a lack of direct quantification of cell properties to provide an integrated feedback system that can also maintain …
Investigation On The Potential Of A Co2 Capture System, Downstream Of The Aftertreatment System For A Heavy-Duty Engine Application, Murchana Pathak
Investigation On The Potential Of A Co2 Capture System, Downstream Of The Aftertreatment System For A Heavy-Duty Engine Application, Murchana Pathak
Dissertations, Master's Theses and Master's Reports
The transportation sector accounts for the second largest source of CO2 emissions after power generation. New Corporate Average Fuel Economy (CAFE) regulations are focusing on improving energy through reduced fuel consumption and greenhouse gas emissions. This work investigates the potential of a CO2 capture system downstream of an aftertreatment system for a heavy-duty engine application. Amine absorption has been described as one of the most effective ways to capture CO2 from the exhaust for point sources. Therefore, using thermal-swing absorption process with potassium carbonate (K2CO3) as the absorbent liquid, a process was analyzed …
Factors Contributing To Elevated Concentrations Of Mercury And Pcbs In Fish In The Inland Lakes Of Michigan's Upper Peninsula And Lake Superior, Mugdha Priyadarshini
Factors Contributing To Elevated Concentrations Of Mercury And Pcbs In Fish In The Inland Lakes Of Michigan's Upper Peninsula And Lake Superior, Mugdha Priyadarshini
Dissertations, Master's Theses and Master's Reports
Mercury (Hg) pollution adversely affects ecosystems and human health. Mercury in the form of methylmercury (MeHg) bioaccumulates in aquatic ecosystems, thereby affecting fish, fish-eating wildlife and humans. The goal of this research was to clarify the effects of environmental factors on MeHg concentrations in fish in the inland lakes of the Upper Peninsula of Michigan. Of the 74 lakes for which data were available, 56 had fish mercury concentrations above the water quality guideline. Multivariate statistical analyses indicated different factors affect fish Hg concentrations in large and small lakes.
Polychlorinated biphenyl (PCB) compounds are a class of persistent, bioaccumulative and …
The Interaction Of Ignition And In-Cylinder Flow On Flame Kernel Development And Its Impacts On Combustion In An Optically Accessible Direct Injection Engine, Yanyu Wang
Dissertations, Master's Theses and Master's Reports
A significant challenge facing spark-ignited (SI) engines to achieve higher efficiency via highly diluted combustion is the quickly increased combustion instability as the dilution level increases. The flow motion variation has been identified as a dominant factor that introduces combustion variability at highly diluted conditions. However, the detailed mechanism of how the variation in flow motion impacts the flame kernel development and introduces combustion instability is only partially understood. This research investigated the impacts of the in-cylinder flow on variability of the ignition and early flame kernel development in a single cylinder direct-injection spark-ignition (DI-SI) optically accessible engine and accessory …
System Architecture Optimization Using Hidden Genes Genetic Algorithms With Applications In Space Trajectory Optimization, Shadi Ahmadi Darani
System Architecture Optimization Using Hidden Genes Genetic Algorithms With Applications In Space Trajectory Optimization, Shadi Ahmadi Darani
Dissertations, Master's Theses and Master's Reports
In this dissertation, the concept of hidden genes genetic algorithms is developed. In system architecture optimization problems, the topology of the solution is unknown and hence, the number of design variables is variable. Hidden genes genetic algorithms are genetic algorithm based methods that are developed to handle such problems by hiding some genes in the chromosomes. The genes in the hidden genes genetic algorithms evolve through selection, mutation, and crossover operations. To determine if a gene is hidden or not, binary tags are assigned to them. The value of the tags determine the status of the genes. Different mechanisms are …
A New Technique To Determine Accommodation Coefficients Of Cryogenic Propellants, Kishan Bellur
A New Technique To Determine Accommodation Coefficients Of Cryogenic Propellants, Kishan Bellur
Dissertations, Master's Theses and Master's Reports
The control of propellant boil-off is essential in long-term space missions. However, a clear understanding of cryogenic propellant phase change and the values of accommodation coefficients are lacking. To that effect, a new method to determine accommodation coefficients using a combination of neutron imaging, thin film evaporation modeling and CFD modeling has been established. Phase change experiments were conducted in the BT-2 Neutron Imaging Facility at the National Institute of Standards and Technology (NIST) by introducing cryogenic vapor (H2 and CH4) at a set pressure into Al6061 and SS316L test cells placed inside a 70mm cryostat. Condensation is achieved by …
Linear Ring Resonator Modulator For Microwave Photonic Links, Arash Hosseinzadeh
Linear Ring Resonator Modulator For Microwave Photonic Links, Arash Hosseinzadeh
Dissertations, Master's Theses and Master's Reports
Modulators within Microwave photonic links (MPLs) encode Radio Frequency (RF) signal information to the optical domain for transmission in applications such as wireless access networks and antenna remoting exploiting advantages optical fiber offers over RF coaxial cables including bandwidth, loss, size, weight, and immunity to electromagnetic interference. A critical figure-of-merit in MPLs is spur-free-dynamic-range (SFDR) defining the range of RF signal power a MPL transmits without distortion. Current Mach-Zehnder Interference (MZI) modulators used in MPLs limit the SFDR because of the associated nonlinear sinusoidal transfer function.
A rigorous theoretical method is developed followed by design, fabrication, and testing to investigate …