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Articles 1 - 30 of 1945

Full-Text Articles in Engineering

It’S Art About Water Treatment! An Interview With Mallory Chaput, The Artist Inspiring Future Water Leaders-One Artwork At A Time, Swati Hegde Apr 2022

It’S Art About Water Treatment! An Interview With Mallory Chaput, The Artist Inspiring Future Water Leaders-One Artwork At A Time, Swati Hegde

wH2O: The Journal of Gender and Water

This article throws a spotlight on Mallory Chaput, an artist inspiring future water leaders to take up water careers. Through her coloring pages, paintings, and comics about the water treatment, Mallory is helping children re-imagine the water sector. Originally a landscaper, Mallory developed a profound interest in water and wastewater treatment and learned about it by visiting plants, talking to professionals, and studying engineering books. This article is a transcript of an interview with Mallory, featuring her background, her imaginative creations and her future goals.


Where There Are No Sewers: The Toilet Cleaners Of Lucknow, Sharada Prasad, Isha Ray Apr 2022

Where There Are No Sewers: The Toilet Cleaners Of Lucknow, Sharada Prasad, Isha Ray

wH2O: The Journal of Gender and Water

Enormous progress has been made in the global effort to provide safe and affordable toilets for the world’s poorest citizens since World Toilet Day was first declared in 2001. Significant strides have been made in “reinventing” toilet designs for low-income, water-short, un-sewered urban zones; celebrities such as Bill Gates and Matt Damon have brought this once-taboo topic into the open; and the Prime Minister of India – the country with the highest number of people still practicing open defecation – has publicly declared that his country needs toilets over temples.

Well over 2 billion people today lack access to basic sanitation ...


El Agua Es Oro: A Human Centered Solution For The City Of Cochabamba, Bolivia, Natalia Mendoza, Camilia Olmedo Apr 2022

El Agua Es Oro: A Human Centered Solution For The City Of Cochabamba, Bolivia, Natalia Mendoza, Camilia Olmedo

wH2O: The Journal of Gender and Water

The purpose of El Agua Es Oro (The Water is Gold) is to satisfy social needs, specifically for women living in peri-urban areas, with a more advanced efficiency. El Agua Es Oro creates an added value for people’s well-being by maximizing socio-environmental context and not just focusing on for-profit economics. Nevertheless, it is noteworthy to generate economic resources to sustain the impact that the organization seeks to achieve. El Agua Es Oro is a social enterprise based on the application of social innovation with the methodology and tools of a people-centered design, focusing on teenage girls and women. The ...


Climate Change, Differential Impacts On Women And Gender Mainstreaming: A Case Study Of East Rapti Watershed, Nepal, Anupama Ray Apr 2022

Climate Change, Differential Impacts On Women And Gender Mainstreaming: A Case Study Of East Rapti Watershed, Nepal, Anupama Ray

wH2O: The Journal of Gender and Water

Women and water share a great deal of nexus in several ways. However, women have still minimal control over the management of water resources, making them more vulnerable to climate change. This paper assesses how climate change impacts differently across different women groups using an intersectionality lens, thereby exploring the situation of gender mainstreaming in water sector in three communities, namely, Karaiya, Basauli, and Dadagaun in Khairahani Municipality located in the East Rapti watershed, Nepal. In this perception- based study, we conducted three key informant interviews and household interviews with 45 women of different castes, ages, communities, education levels, and ...


Gender In The Water Industry One Man Of Transgender Experience’S Story, Ari Copeland Apr 2022

Gender In The Water Industry One Man Of Transgender Experience’S Story, Ari Copeland

wH2O: The Journal of Gender and Water

is a complex topic Most people often confuse gender and sex; Most folks don’t realize that there are at least 57 genders and gender is a spectrum Some people within our workplace and the water industry don’t identify as a man or a woman, and/or their gender is more fluid (gender-expansive. In our day-to-day interactions with others, we often assume someone’s gender based on their appearance, mannerisms, and other social cues that vary depending on the culture Additionally, assuming everyone fits into the gender binary (just men and women is often-times a barrier to being inclusive ...


Exploring Sustainable Degrowth-Based Adaptation To Climate Change-Aggravated Water Insecurity In Parts Of Rural India: A Gender Relations Approach, Nairita Roy Chaudhuri Apr 2022

Exploring Sustainable Degrowth-Based Adaptation To Climate Change-Aggravated Water Insecurity In Parts Of Rural India: A Gender Relations Approach, Nairita Roy Chaudhuri

wH2O: The Journal of Gender and Water

This article reviews the theoretical concept of ‘sustainable adaptation’ to climate change and water scarcity using a gender-relations approach by answering the following questions: i) What is a sustainable adaptation to climate change? ii) Based on a literature review, how does gender interact with climate change adaptation to water scarcity and droughts in rural India? (iii) How do the concepts of sustainable adaptation, degrowth, and gender relations interact on the ground, pertaining to water justice?

The paper argues that climate change adaptation and development goals can harmonize only if they rectify root causes of vulnerabilities. For adaptation actions to yield ...


Access To Clean Water For Women In Iraq: Accorded Rights, Bakir H. Amin Feb 2022

Access To Clean Water For Women In Iraq: Accorded Rights, Bakir H. Amin

wH2O: The Journal of Gender and Water

After the Iraqi government was established in 1921, it had a little problem receiving a sufficient quantity of high-quality water from the Euphrates and Tigris Rivers. However, the upstream countries of Turkey, Syria, and Iran soon built dams and canal on the shared rivers in the latter half of the 20th century. Furthermore, engaged in prolonged military conflicts such as the Iranian-Iraq War of the 1980s, the Gulf War of the 1990s, the US-led invasion of Iraq in 2003, and the ongoing ISIS occupation in the region, Iraq’s political, economic, and social infrastructures have been crippled in the wake ...


Forward Kinematics And Control Of A Segmented Tunable-Stiffness 3-D Continuum Manipulator, Shivangi Misra, Cynthia Sung Jan 2022

Forward Kinematics And Control Of A Segmented Tunable-Stiffness 3-D Continuum Manipulator, Shivangi Misra, Cynthia Sung

Lab Papers (GRASP)

In this work, we consider the problem of controlling the end effector position of a continuum manipulator through local stiffness changes. Continuum manipulators offer the advantage of continuous deformation along their lengths, and recent advances in smart material actuators further enable local compliance changes, which can affect the manipulator's bulk motion. However, leveraging local stiffness change to control motion remains lightly explored. We build a kinematic model of a continuum manipulator as a sequence of segments consisting of symmetrically arranged springs around the perimeter of every segment, and we show that this system has a closed form solution to ...


Sop Of Be-04, Hiromichi Yamamoto Dec 2021

Sop Of Be-04, Hiromichi Yamamoto

Standard Operating Procedures

The standard operating procedure of BE-04


Sop Of Met-03, Hiromichi Yamamoto Dec 2021

Sop Of Met-03, Hiromichi Yamamoto

Standard Operating Procedures

The standard operating procedure of MET-03


Sop Of Met-01, Hiromichi Yamamoto Dec 2021

Sop Of Met-01, Hiromichi Yamamoto

Standard Operating Procedures

The standard operating procedure of MET-01


Sop Of Met-02, Hiromichi Yamamoto Dec 2021

Sop Of Met-02, Hiromichi Yamamoto

Standard Operating Procedures

The standard operating procedure of MET-02


Sop Of Met-04, Hiromichi Yamamoto Dec 2021

Sop Of Met-04, Hiromichi Yamamoto

Standard Operating Procedures

The standard operating procedure of MET-04


Make And Characterize Microfluidic Devices With Gelatin: Do-It-Yourself (Diy) Laboratory At Home, Marissa Youderian, Xilai Song, Mark Lancaster, Ahana Jhamb, David J. Jones, Gyuseok L. Kim Nov 2021

Make And Characterize Microfluidic Devices With Gelatin: Do-It-Yourself (Diy) Laboratory At Home, Marissa Youderian, Xilai Song, Mark Lancaster, Ahana Jhamb, David J. Jones, Gyuseok L. Kim

Educational Materials

Microfluidic devices have been fabricated with gelatin and paper clips. Optimization of fabrication and characterization process has been carried out systemically by varying gelatin-to-water ratio, bonding time and connector type. We find that the higher gelatin-to-water ratio and the luer lock syringe tip provide a greater success rate, whereas the influence of bonding time is limited. The Reynolds number was calculated to identify whether the fluid shows laminar or turbulent flow.


Magnetron Sputtering Explorer14 Standard Operating Procedure, Hiromichi Yamamoto Nov 2021

Magnetron Sputtering Explorer14 Standard Operating Procedure, Hiromichi Yamamoto

Standard Operating Procedures

Explorer14 standard operating procedure


Mems Device Demonstration For High School Students Or Nonspecialists, Jeffrey Meng, Gyuseok L. Kim, Gabriel Unger Oct 2021

Mems Device Demonstration For High School Students Or Nonspecialists, Jeffrey Meng, Gyuseok L. Kim, Gabriel Unger

Educational Materials

Micro-electromechanical systems (MEMS) devices have many unique advantages, and offer an exciting entrance for students into the field of nanotechnology and nanofabrication. In this article, an educational hands-on laboratory protocol with MEMS devices is proposed. Using a paper airplane, an Arduino, and the MPU 6050 MEMS accelerometer/gyroscope sensor students are able to create a graphical aircraft attitude indicator. The data is then processed on the Arduino, which is connected to a computer. The computer can then run graphics software displaying a digital aircraft attitude indicator showing the roll and pitch of the aircraft live.


Improving Neural Network Robustness Via Persistency Of Excitation, Kaustubh Sridhar, Oleg Sokolsky, Insup Lee, James Weimer Oct 2021

Improving Neural Network Robustness Via Persistency Of Excitation, Kaustubh Sridhar, Oleg Sokolsky, Insup Lee, James Weimer

Departmental Papers (CIS)

Improving adversarial robustness of neural networks remains a major challenge. Fundamentally, training a neural network via gradient descent is a parameter estimation problem. In adaptive control, maintaining persistency of excitation (PoE) is integral to ensuring convergence of parameter estimates in dynamical systems to their true values. We show that parameter estimation with gradient descent can be modeled as a sampling of an adaptive linear time-varying continuous system. Leveraging this model, and with inspiration from Model-Reference Adaptive Control (MRAC), we prove a sufficient condition to constrain gradient descent updates to reference persistently excited trajectories converging to the true parameters. The sufficient ...


Improving Healthspan Through Patient-Derived Artificial Organs From Induced Pluripotent Stem Cells And Two-Photon Polymerization, Connor Espenshade Sep 2021

Improving Healthspan Through Patient-Derived Artificial Organs From Induced Pluripotent Stem Cells And Two-Photon Polymerization, Connor Espenshade

Protocols and Reports

Senescence, from the shortening of telomeres, accumulation of mutations, epigenetic hypomethylation, and other causes, begins an eventual cycle of decline in every patient. Stem cells disappear as a function of age, which in turn impairs cellular replication. Moreover, when fully differentiated cells are induced back into induced pluripotent stem cells (iPSCs), they not only revert to a state of pre-differentiation, but also to a younger cellular age. Their aging clocks turn back: their telomeres become longer and DNA methylation reverts back to an earlier age. It should therefore be possible to use iPSCs to replace the missing stem cells from ...


Motivation Dynamics For Autonomous Composition Of Navigation Tasks, Paul B. Reverdy, Vasileios Vasilopoulos, Daniel E. Koditschek Aug 2021

Motivation Dynamics For Autonomous Composition Of Navigation Tasks, Paul B. Reverdy, Vasileios Vasilopoulos, Daniel E. Koditschek

Departmental Papers (ESE)

We physically demonstrate a reactive sensorimotor architecture for mobile robots whose behaviors are generated by motivation dynamics. Motivation dynamics uses a continuous dynamical system to reactively compose low-level control vector fields using valuation functions which capture the potentially competing influences of external stimuli relative to the system's own internal state. We show that motivation dynamics 1) naturally accommodates external stimuli through standard signal processing tools, and 2) can effectively encode a repetitive higher-level task by composing several low-level controllers to achieve a limit cycle in which the robot repeatedly navigates towards two alternatively valuable goal locations in a commensurately ...


Detecting Oods As Datapoints With High Uncertainty, Ramneet Kaur, Susmit Jha, Anirban Roy, Sangdon Park, Oleg Sokolsky, Insup Lee Jul 2021

Detecting Oods As Datapoints With High Uncertainty, Ramneet Kaur, Susmit Jha, Anirban Roy, Sangdon Park, Oleg Sokolsky, Insup Lee

Departmental Papers (CIS)

Deep neural networks (DNNs) are known to produce incorrect predictions with very high confidence on out-of-distribution inputs (OODs). This limitation is one of the key challenges in the adoption of DNNs in high-assurance systems such as autonomous driving, air traffic management, and medical diagnosis. This challenge has received significant attention recently, and several techniques have been developed to detect inputs where the model’s prediction cannot be trusted. These techniques detect OODs as datapoints with either high epistemic uncertainty or high aleatoric uncertainty. We demonstrate the difference in the detection ability of these techniques and propose an ensemble approach for ...


Origami-Inspired Robot That Swims Via Jet Propulsion, Zhiyuan Yang, Dongsheng Chen, David J. Levine, Cynthia R. Sung Jul 2021

Origami-Inspired Robot That Swims Via Jet Propulsion, Zhiyuan Yang, Dongsheng Chen, David J. Levine, Cynthia R. Sung

Lab Papers (GRASP)

Underwater swimmers present unique opportunities for using bodily reconfiguration for self propulsion. Origami-inspired designs are low-cost, fast to fabricate, robust, and can be used to create compliant mechanisms useful in energy efficient underwater locomotion. In this paper, we demonstrate an origami-inspired robot that can change its body shape to ingest and expel water, creating a jet that propels it forward similarly to cephalopods. We use the magic ball origami pattern, which can transform between ellipsoidal (low volume) and spherical (high volume) shapes. A custom actuation mechanism contracts the robot to take in fluid, and the inherent mechanics of the magic ...


Reconfiguring Non-Convex Holes In Pivoting Modular Cube Robots, Daniel Adam Feshbach, Cynthia Sung Jul 2021

Reconfiguring Non-Convex Holes In Pivoting Modular Cube Robots, Daniel Adam Feshbach, Cynthia Sung

Lab Papers (GRASP)

We present an algorithm for self-reconfiguration of admissible 3D configurations of pivoting modular cube robots with holes of arbitrary shape and number. Cube modules move across the surface of configurations by pivoting about shared edges, enabling configurations to reshape themselves. Previous work provides a reconfiguration algorithm for admissible 3D configurations containing no non-convex holes; we improve upon this by handling arbitrary admissible 3D configurations. The key insight specifies a point in the deconstruction of layers enclosing non-convex holes at which we can pause and move inner modules out of the hole. We prove this happens early enough to maintain connectivity ...


Verisig 2.0: Verification Of Neural Network Controllers Using Taylor Model Preconditioning, Radoslav Ivanov, Taylor Carpenter, James Weimer, Rajeev Alur, George Pappas, Insup Lee Jul 2021

Verisig 2.0: Verification Of Neural Network Controllers Using Taylor Model Preconditioning, Radoslav Ivanov, Taylor Carpenter, James Weimer, Rajeev Alur, George Pappas, Insup Lee

Departmental Papers (CIS)

This paper presents Verisig 2.0, a verification tool for closed-loop systems with neural network (NN) controllers. We focus on NNs with tanh/sigmoid activations and develop a Taylor-model-based reachability algorithm through Taylor model preconditioning and shrink wrapping. Furthermore, we provide a parallelized implementation that allows Verisig 2.0 to efficiently handle larger NNs than existing tools can. We provide an extensive evaluation over 10 benchmarks and compare Verisig 2.0 against three state-of-the-art verification tools. We show that Verisig 2.0 is both more accurate and faster, achieving speed-ups of up to 21x and 268x against different tools, respectively.


Modelguard: Runtime Validation Of Lipschitz-Continuous Models, Taylor J. Carpenter, Radoslav Ivanov, Insup Lee, James Weimer Jul 2021

Modelguard: Runtime Validation Of Lipschitz-Continuous Models, Taylor J. Carpenter, Radoslav Ivanov, Insup Lee, James Weimer

Departmental Papers (CIS)

This paper presents ModelGuard, a sampling-based approach to runtime model validation for Lipschitz-continuous models. Although techniques exist for the validation of many classes of models, the majority of these methods cannot be applied to the whole of Lipschitz-continuous models, which includes neural network models. Additionally, existing techniques generally consider only white-box models. By taking a sampling-based approach, we can address black-box models, represented only by an input-output relationship and a Lipschitz constant. We show that by randomly sampling from a parameter space and evaluating the model, it is possible to guarantee the correctness of traces labeled consistent and provide a ...


Effect Of Developer Temperature On Photoresist Contrast In Grayscale Lithography, Dale Farnan, George Patrick Watson May 2021

Effect Of Developer Temperature On Photoresist Contrast In Grayscale Lithography, Dale Farnan, George Patrick Watson

Protocols and Reports

SPR 220-3 photoresist was spin-coated onto a silicon wafer, exposed using a Heidelberg DWL66+ laserwriter at different laser powers, and developed at different temperatures. The effect of developer temperature on photoresist contrast was examined. Results show that increasing developer temperature decreased photoresist contrast and increased required dose.


Are Certain Countries More Nimble In Completing Major Infrastructure Projects? A Cross Country Analysis Of Infrastructure Capital Efficacy, Deniz Yilmaz May 2021

Are Certain Countries More Nimble In Completing Major Infrastructure Projects? A Cross Country Analysis Of Infrastructure Capital Efficacy, Deniz Yilmaz

Joseph Wharton Scholars

Discovering the drivers that lead to faster and more efficient completion of major infrastructure projects is important because there is a wide range when it comes to countries’ ability to complete projects in a time and cost effective manner. This study looks at a dataset of the longest bridges in the world, which includes highways, high speed rail, expressways, and roads among other transportation infrastructure projects from 41 countries. This paper aims to discover whether some countries or regions appear to complete infrastructure projects faster than others and find which variables lead to faster completion of bridges as measured by ...


Reimagining Robotic Walkers For Real-World Outdoor Play Environments With Insights From Legged Robots: A Scoping Review, Abriana Stewart-Height, Daniel E. Koditschek, Michelle J. Johnson May 2021

Reimagining Robotic Walkers For Real-World Outdoor Play Environments With Insights From Legged Robots: A Scoping Review, Abriana Stewart-Height, Daniel E. Koditschek, Michelle J. Johnson

Departmental Papers (ESE)

PURPOSE

For children with mobility impairments, without cognitive delays, who want to participate in outdoor activities, existing assistive technology (AT) to support their needs is limited. In this review, we investigate the control and design of a selection of robotic walkers while exploring a selection of legged robots to develop solutions that address this gap in robotic AT.

METHOD

We performed a comprehensive literature search from four main databases: PubMed, Google Scholar, Scopus, and IEEE Xplore. The keywords used in the search were the following: “walker”, “rollator”, “smart walker”, “robotic walker”, “robotic rollator”. Studies were required to discuss the control ...


Reactive Planning For Mobile Manipulation Tasks In Unexplored Semantic Environments, Vasileios Vasilopoulos, Yiannis Kantaros, George J. Pappas, Daniel E. Koditschek May 2021

Reactive Planning For Mobile Manipulation Tasks In Unexplored Semantic Environments, Vasileios Vasilopoulos, Yiannis Kantaros, George J. Pappas, Daniel E. Koditschek

Departmental Papers (ESE)

Complex manipulation tasks, such as rearrangement planning of numerous objects, are combinatorially hard problems. Existing algorithms either do not scale well or assume a great deal of prior knowledge about the environment, and few offer any rigorous guarantees. In this paper, we propose a novel hybrid control architecture for achieving such tasks with mobile manipulators. On the discrete side, we enrich a temporal logic specification with mobile manipulation primitives such as moving to a point, and grasping or moving an object. Such specifications are translated to an automaton representation, which orchestrates the physical grounding of the task to mobility or ...


Biofuels For Aviation, Chase Novak, Thomas Vasquez, Molly Zawacki Apr 2021

Biofuels For Aviation, Chase Novak, Thomas Vasquez, Molly Zawacki

Senior Design Reports (CBE)

Paraffinic Kerosene fuels are the backbone of commercial air travel. Kerosene fuels are primarily derived from petroleum processing and contribute significantly to carbon emissions globally. A variety of processes have been proposed to create renewable or semi-renewable sources of kerosene fuel suitable for aviation. One such process outlined in a 2019 white paper published by Gevo proposes the use of bio-based alcohol feed stocks to produce isobutanol which may be converted to kerosene mixtures through well-established dehydration and oligomerizations processes. The proposed Alcohol to Jet Fuel Pathway (ATJ-SPK) is a potentially net carbon neutral process which can greatly reduce the ...


Protein Purification To Produce Edible Soybean Protein, Miyu Ono, Gracelynn Soesanto, Alia Wallenstrom Apr 2021

Protein Purification To Produce Edible Soybean Protein, Miyu Ono, Gracelynn Soesanto, Alia Wallenstrom

Senior Design Reports (CBE)

This project recommends a design for a soy processing facility to produce soy protein concentrates (SPC), soy oil and soy molasses from dehulled soybeans. Utilities were minimized, wherever possible by evaluating whether streams within the system had the capacity to heat or cool other processes. The plant has a production capacity of 170 MM lb soy protein concentrate/year and will be located in Decatur, IL. The proposed design also yields 114 MM lb soy oil/year and 62 MM lb soy molasses/year. The SPC, soy oil and soy molasses have less than 2 PPM residual solvent concentrations and ...