Penn Engineering Events

MSE Seminar: “Scalable Multifunctional Nanoarchitectures for Energy Storage”
2019-10-24 10:45 - 11:45 (America/New_York) | Auditorium, LRSM Building, 3231 Walnut Street, Philadelphia, PA, 19104, United States

CBE Seminar: "Toward Platinum-free Fuel Cells for Affordable Zero-emission Vehicles”
2019-10-23 15:00 - 16:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract:
One of the grand challenges facing humanity today is the development of an alternative energy system that is safe, clean, and sustainable. A Distributed Renewable Electrochemical Energy and Mobility System (DREEMS) can meet this challenge. At the foundation of this new energy system, we have chosen to study fuel cells, electrolyzers, and flow batteries. For all these devices polymer electrolytes play a critical role in controlling their performance, cost, and durability, and thus their economic viability. In this presentation, I will focus on our recent work on Hydroxide Exchange Membrane Fuel Cells (HEMFCs). More specifically, I will focus on our recent discovery of a new family of polymer hydroxide (and other anions) conductors that is chemically stable, ionically conductive, and mechanically robust; and HEMFCs with this new class of polymers showed record fuel cell performance and stability at 95 ºC. I will also briefly introduce a new class of crystalline porous polymers that are the most stable among all crystalline porous materials.

ESE Seminar: "Foundations of Deep Learning and Applications in Medicine"
2019-10-23 12:00 - 13:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract: Recent advances in machine learning, computer vision, natural language processing, and robotics, offer a tremendous opportunity to transform medicine, from reactive and hospital centered to proactive and patient-centered. To fulfill this promise, new methods need to be developed which are more interpretable, can handle data at multiple spatial and temporal scales, and are robust to data heterogeneity and limited amounts of annotations. The first part of this talk will overview our recent work on the theory of deep learning, including sufficient conditions to guarantee that local minima are globally optimal, as well as an analysis of the optimization and regularization properties of dropout. The second part of this talk will overview our recent work on the development of methods for interpreting biomedical datasets arising in blood cell analysis, regenerative medicine, digital pathology, brain imaging, surgery and rehabilitation therapy.

CIS Seminar: “Learning in dynamic environments”
2019-10-22 15:00 - 16:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract:
In many online systems participants use data and algorithms to experiment and learn how to best use the system. Examples include traffic routing as well as online auctions. Game theory classically studies Nash equilibrium as the outcome of selfish interaction, and has many examples illustrating that selfish behavior can lead to suboptimal outcome for all participants. Over the last decade, we developed good understanding how to quantify the impact of strategic user behavior on overall performance in Nash equilibria of games. In this talk we will focus on games where players use a form of learning that helps them adapt to the environment. We ask if the quantitative guarantees obtained for Nash equilibria extend to such out of equilibrium game play, possibly even in dynamically changing environments?

CBE Thesis Defense: "A Heterogeneous and Multiscale Modeling Framework to Develop Patient-Specific Pharmacodynamic System Models in Cancer"
2019-10-22 14:00 - 16:00 | Raisler Lounge (Room 225), Towne Building, 220 South 33rd Street, Philadelphia, PA, 19104, United States
Thesis Committee: Ravi Radhakrishnan, Ph.D., advisor; Dennis Discher, PhD; Scott Diamond, PhD; and Wei Guo, PhD

MEAM Seminar: "Architecture in Biological Materials: A Template for Toughness Enhancement, or a Siren Song?"
2019-10-22 10:30 - 12:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Structural biological materials, such as animal bones and shells, display remarkable mechanical properties despite being composed of quite simple and ordinary constituent materials. For example, the toughness of nacre, a structural biological material found in the shells of some mollusks, is orders of magnitude higher than that of its primary constituent—the calcium based mineral aragonite. A number of structural biological materials that display toughness enhancement also possess a lamellar architecture consisting of alternating layers of ceramic and organic phases. It is believed that a structural biological material’s intricate architecture—the geometric arrangement of these phases—is responsible for the observed property enhancements. Within the bio-mimetics community, there is currently great interest in reproducing these architectures in synthetic materials using micro-fabrication and 3D printing in order to achieve the property enhancements observed in structural biological materials.
In this talk I will present experimental and computational mechanics results that show that correctly identifying the connection between a structural biological material’s architecture and any property enhancements can be a very delicate process. Specifically, I will present experiments that characterize the toughness properties of the skeletal elements of the marine sponge Euplectella aspergillum, called spicules. I will show that despite possessing a lamellar architecture that is very similar to that seen in nacre, the spicules do not display a significant toughness enhancement. Through mechanics modeling, I argue that the spicule’s lamellar architecture is connected to their ability to bend more without failing, i.e., to their strength, rather than their toughness. These results serve as a reminder that any efforts aimed at reproducing a structural biological material’s architecture and property enhancements in synthetic materials should be prefaced by a careful investigation of the structural biological material itself.
References
[1] Monn, Michael A., James C. Weaver, Tianyang Zhang, Joanna Aizenberg, and
Haneesh Kesari. “New functional insights into the internal architecture of the
laminated anchor spicules of Euplectella aspergillum.” Proceedings of the National
Academy of Sciences 112, no. 16 (2015): 4976-4981.
[2] Monn, Michael A., and Haneesh Kesari. “A new structure-property connection in
the skeletal elements of the marine sponge Tethya aurantia that guards against
buckling instability.” Scientific reports 7 (2017): 39547.

EWaste Collection
2019-10-22 10:00 - 14:00 | Lobby and Mezzanine, Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
We will be collecting EWASTE items in Levine Lobby on Tuesday in support of Energy Week @ Penn campaign.
This is a great opportunity to properly recycle non-traditional items such as:

computers & printers
computer accessories (keyboards, mice)
Monitors, TVs, Displays
Mobile phones
household electronics (anything with a plug!)
light bulbs
non-recyclable glass

ESE Seminar: "Information Security for the Connected World"
2019-10-18 15:00 - 16:00 | PICS Conference Room 534 – A Wing , 5th Floor, 3401 Walnut Street, Philadelphia, PA, 19104, United States
Abstract: An all-wireless vision connecting billions of devices is finally in sight with the Internet-of-Everything paradigm. This vision entails large networks with dynamic connectivity, ad hoc formation and heterogeneous nodes. Central to be able to integrate all our lives to this massive virtual domain is security and privacy of the information that flows through it. Current wireless systems have security of information as an add-on to current design, and rely on application layer protocols, which have worked well for the scale and the resources of the systems to date. Going forward however, with massive scale formation of networks of asymmetric resources, these protocols involving key exchanges and shared randomness for security may prove to be less than practical.
Securing information at the foundation of system design can alleviate these issues by replacing or strengthening the present cryptographic solutions. This foundational design approach brings us to information theoretic security for the all- connected world. In this talk, we will provide an overview of this approach that relies on local randomness and produces information theoretic security guarantees, e.g, for confidentiality and authentication, utilizing the properties of the transmission medium. We will review the insights that have emerged when information security is included as a design primitive and provide the state of the art directions towards realizing the potential of this approach. We will also introduce models where this approach can be integrated with encryption for nodes with local memory storage.

MSE Seminar: “Science and Applications of Topological Photonics across the Electromagnetic Spectrum”
2019-10-17 10:45 - 11:45 | Auditorium, LRSM Building, 3231 Walnut Street, Philadelphia, PA, 19104, United States
The 2016 Nobel Prize in Physics was awarded to Kosterlitz, Thouless, and Haldane for their pioneering theoretical work on the novel and counter-intuitive phases of matter that are now referred to as topological phases. Almost half a century after these researchers applied powerful mathematical techniques of topology to condensed matter systems, a new rapidly developing area is taking shape, now in the field of photonics. While very different in many respects from their condensed matter counterparts, topological phases of light share some of their unique properties that make topological photonics particularly suitable for practical applications. Just as the inventors of photonic crystals (often referred to as the “semiconductors of light”) borrowed crucial ideas, such as propagation bands, bandgaps, and Brillouin zone, from condensed matter physics, so do the researchers in the field of topological photonics that attempts to emulate the key concepts from low-dimensional topological materials. Those include photonic topological insulators (PTIs), reflection-less edge states that propagate along the domain walls of the PTIs, and spin-polarized/valley-polarized transport.
In this talk, Dr. Shvets will provide an overview of the field, with special emphasis on the photonic emulation of the canonical quantum topological phases such as the Hall, spin-Hall, and valley-Hall phases. He will then describe how such heterogeneous PTIs can be integrated and used for developing novel devices such as compact circulators. Experimental results demonstrating reflection-less transport of topologically protected edge states will be presented. He will also discuss how the ideas from topological photonics can be used for complete reimagining of the architectures of photonic devices such as add/drop filters, delay lines, and logical gates based on the valley degree of freedom of photons (“photonic valleytronics”). Finally, Dr. Shvets will discuss the prospects of realizing reconfigurable topological photonic structures on a nanoscale. The prospects for exciting topologically protected microwaves using high current beams, and using the latter for high-power magnets-free microwave radiation, will also be discussed.

MSE Special Seminar: “What They Don’t Teach You in School that You Need to Succeed in Life”
2019-10-16 15:00 - 16:30 | Glandt Forum, Singh Center for Nanotechnology, 3205 Walnut Street, Philadelphia, PA, 19104, United States

CBE Seminar: "Examining Heterogeneous Populations of Microbes at the Single Cell Level Using Stabilized Emulsions”
2019-10-16 15:00 - 16:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract:
Conventional methods in microbiology can be limited by long assay execution and analysis times, large reagent volumes, and high single-use supply costs. These limitations can be overcome using drop-based microfluidics in which picoliter-sized, water-in-oil emulsions serve as independent microreactors, allowing for the compartmentalization of microbes and high-throughput assaying at the single cell level. Here, drop-based microfluidics is used to interrogate the physiological heterogeneity of P. aeruginosa cells in a microbial population using a technique we name DropSOAC (Drop Stabilization On A Chip). The DropSOAC method stabilizes the position and volume of monodisperse water-in-oil drops with diameters <20 mm within a monolayer array on a microfluidic chip for 24 h. The stability of drops is maintained by soaking the device in a reservoir containing both water and oil in thermodynamic equilibrium. This ensures that phase equilibrium of the drop emulsion fluids within the porous PDMS material structure is maintained during drop incubation and imaging. Continuing this work, we aim to study the rapid emergence of antibiotic resistance now observed in common bacterial strains to find effective treatments for persistent bacterial infections. This will be performed using a microfluidic chip that is capable of encapsulating in parallel, 96 barcoded assay samples in drops using fluorescent particles. Using a custom-built microscope that can read fluorescence from drops at rates of thousands per second, we demonstrate sorting for a particular barcode combination from our droplet library. The results presented here show the potential of drop-based microfluidics for high-throughput assaying of heterogeneous populations of microbes at the single cell level.

PSOC Seminar : "Lessons from the Liver: From Chromosome Segregation to Tissue Regeneration"
2019-10-14 12:00 - 13:00 | PICS Conference Room 534 – A Wing , 5th Floor, 3401 Walnut Street, Philadelphia, PA, 19104, United States

MEAM Doctoral Dissertation Defense: "Problems in Nonlinear Homogenization: Bounds, Estimates, Macroscopic Instabilities, and Post-Bifurcation Response"
2019-10-11 11:00 - 13:00 | Towne 309, 220 S. 33rd Street, Philadelphia, PA, 19104, United States
This talk is concerned with the use of nonlinear homogenization to study the effective response of composites. We look to illustrate the effect that constitutive assumptions have on the methods by which such estimates can be obtained, as well as on the actual effective, or homogenized, response of the material. Although helpful in ensuring existence in a variational setting, convexity is often inconsistent with certain physical requirements (e.g. objectivity). Such is the case of hyperelasticity, the subject of the first part of the talk. The lack of convexity of the stored-energy functions of such hyperelastic systems has long been known to lead to the development of instabilities. When such instabilities do not result in material failure, we look to study the post-bifurcation behavior of the system. We present a framework for doing so, and compute the post-bifurcation response of a laminated hyperelastic composite explicitly under general three-dimensional loading conditions. In the second part of the talk, we will consider the class of magneto-elastic composites, which consist of hyperelastic materials that are also magnetically susceptible. Unlike in the case of hyperelasticity, there lacks a complete mathematical framework for obtaining the effective response of such materials, and researchers have only begun to investigate the potential for instabilities in these materials. We therefore look to generalize the same methodology used successfully in the purely mechanical context to study the post-bifurcation behavior of magneto-elastic composites. This in part requires a rigorous generalization of the theoretical aspects that underlie the method. With this, we calculate the post-bifurcation response of a magneto-elastic material under general plane-strain loading conditions with a magnetic field applied in the plane of deformation.

BE Doctoral Dissertation Defense: Human organ-on-chip systems for the study of biomechanical forces in health and disease
2019-10-09 15:30 - 17:00 | Glandt Forum, Singh Center for Nanotechnology, 3205 Walnut Street, Philadelphia, PA, 19104, United States

Cultivating Cultures of Ethical STEM: Institutional Transformation and Industrial Research Approaches and Findings
2019-10-08 15:00 - 16:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
This two-part talk will describe the scope of work and emergent findings of two ongoing National Science Foundation Cultivating Cultures of Ethical STEM (CCESTEM) projects. Each project seeks to provide strategies for the design, assessment, and research of learners’ ethical formation. The first project, an Institutional Transformation CCESTEM project (Award #1737157), seeks to utilize Faculty Learning Communities to refine instructional approaches to the Integrated Community-Engaged Learning and Ethical Reflection (I-CELER) framework among faculty in two departments at Indiana University Purdue University – Indianapolis (IUPUI). The second project, a Standard Research CCESTEM project (Award #1737303), seeks to explore variations in ways of experience ethics among engineering practitioners in the health products industry. Taken together, these projects provide insights for the design of learning environments to foster STEM students’ and practitioners’ ethical dispositions and reasoning skills.

ESE Seminar: "2D Materials for Unconventional Devices: From Flexible/Wearable Tattoo Sensors to Monolayer Memory"
2019-10-08 11:00 - 12:00 | PICS Conference Room 534 – A Wing , 5th Floor, 3401 Walnut Street, Philadelphia, PA, 19104, United States
Abstract: This talk will present our latest research adventures on 2D nanomaterials towards greater scientific understanding and advanced engineering applications. In particular the talk will highlight our work on flexible electronics, zero-power devices, monolayer memory (atomristors), non-volatile RF switches, and wearable tattoo sensors. Non-volatile memory devices based on 2D materials are an application of defects and is a rapidly advancing field with rich physics that can be attributed to sulfur vacancies or metal diffusion. Atomistic modeling and atomic resolution imaging are contemporary tools under use to elucidate the memory phenomena. Likewise, from a practical point, electronic tattoos based on graphene have ushered a new material platform that has highly desirable practical attributes including optical transparency, mechanical imperceptibility, and is the thinnest conductive electrode sensor that can be integrated on skin for physiological measurements. Much of these research achievements have been published in nature, IEEE and ACS journals, and widely covered by the news media including Time magazine, BBC, Nature news, IEEE spectrum, and several dozen media outlets.
References:
[1] Akinwande, et al., “Graphene and 2D Materials for Silicon Technology,” Nature, 2019.
[2] X. Wu, R. Ge, P.-A. Chen, H. Chou, Z. Zhang, Y. Zhang, S. Banerjee, M.-H. Chiang, J. C. Lee, and D. Akinwande, “Thinnest Nonvolatile Memory Based on Monolayer h-BN,” Advanced Materials, p. 1806790, 2019.
[3] M. Kim, R. Ge, X. Wu, X. Lan, J. Tice, J. C. Lee, and D. Akinwande, “Zero-static power radio-frequency switches based on MoS2 atomristors,” Nature Communications, vol. 9, p. 2524, 2018.
[4] S. Kabiri Ameri, R. Ho, H. Jang, L. Tao, Y. Wang, L. Wang, D. M. Schnyer, D. Akinwande, and N. Lu, “Graphene Electronic Tattoo Sensors,” ACS Nano, vol. 11, 2017.

MEAM Seminar: "Scalable Fabrication of Nanostructured Energy Storage Systems"
2019-10-08 10:30 - 12:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
The demand for autonomous devices, including intelligent sensor platforms for IOT applications, is driving a parallel need for efficient energy storage systems that are inexpensive to produce, exhibit high power and energy densities, and occupy a minimum footprint on the device. Necessary enhancement in the performance of batteries and supercapacitors can be realized by fabrication of hierarchical 3D architectures with dimensional control ranging from the nm to the macroscale, however the most promising structures have proven difficult to achieve using approaches suitable for large scale production.
We are fabricating energy storage devices using combinations of nanoimprint lithography, self-assembly, and novel approaches to high-rate materials synthesis including rapid photothermal processing. In one example, 3D lithium-ion microbatteries are prepared via imprint lithography using inks comprised of LiMn2O4 and Li4Ti5O12 nanoparticles and the battery cell is integrated vertically through layer-by-layer (LBL) assembly. The batteries are shown to possess superior capacity retention and high-power density. We also fabricate hierarchical graphene/carbon/FeOx nanoparticle composite anodes for high performance Li ion batteries using a combination of imprint lithography and photothermal processing, wherein multilayer graphene embedded within a porous carbon matrix is generated in situ from a simple precursor film, eliminating the need for externally sourced graphene. The approaches employed are rapid and highly efficient, enabling batch fabrication for 3D microbattery systems as well as the roll-to-roll production of large energy storage batteries.

PSOC Seminar : "Using mechanics to understand liver cancer models"
2019-10-07 12:00 - 13:00 | Room 337, Towne Building, 220 South 33rd Street, Philadelphia, PA, 19104, United States

PICS Colloquium: Concurrent Atomistic-Continuum Modeling and Simulation of Transport Processes in Crystalline Materials
2019-10-04 14:00 - 15:00 | PICS Conference Room 534 – A Wing , 5th Floor, 3401 Walnut Street, Philadelphia, PA, 19104, United States
Abstract: In this talk we present a concurrent atomistic-continuum (CAC) method for modeling and simulation of transport processes in crystalline materials. The CAC formulation extends the Irving-Kirkwood procedure for deriving transport equations and fluxes for homogenized molecular systems to that for polyatomic crystalline materials by employing a concurrent two- level structural description of crystals. A multiscale representation of conservation laws is formulated that holds instantaneously, as a direct consequence of Newton’s second law, using the mathematical theory of generalized functions. Finite element (FE) solutions to the conservation equations, as well as fluxes and temperature in the FE representation, are introduced, followed by numerical examples of atomic-scale structures of interfaces, dynamics of fracture and dislocations, and phonon transport in multiscale structured materials. In addition to providing a methodology for concurrent multiscale simulation of transport processes under a single theoretical framework, the CAC formulation can also be used to compute fluxes (stress and heat flux) in atomistic and coarse-grained atomistic simulations.

CIS Seminar: “A Geometric Perspective on Computing Motion”
2019-10-03 15:00 - 16:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract:
The connections between geometry and mechanics have been explored for centuries. How these connections shape computation is a question we are just beginning to explore.
If computers can predict how materials move and deform, they can help us to understand, anticipate and manipulate the physical world. Our group develops models and algorithms that capture the characteristic behavior of a mechanical system. We focus on a geometric interpretation of the physics. Building a discrete geometric picture from the ground up, we mimic the axioms, structures, and symmetries of the smooth setting. The result is a readily computable model that preserves invariants and conservation laws.
We develop models for elastic rods, thin shells, liquid threads, droplets, soap films, and granular media. As we explore applications ranging from flagellar propulsion and robotics to fashion design, we learn about the potential for impact on art, medicine, engineering and scientific research.

BE Seminar: "Developing neuroengineering solutions of biomedical relevance using crayfish as a model system"
2019-10-03 12:00 - 13:30 | Room 337, Towne Building, 220 South 33rd Street, Philadelphia, PA, 19104, United States
In my talk, I will first describe one of the main projects in my lab that investigates the underlying cellular-molecular mechanisms for changes in alcohol sensitivity of crayfish with different prior social experiences. In this context, I will explain why “simple” invertebrates may provide unique advantages for studying complex phenomena such as socially-dependent drug effects. Crayfish are inexpensive and easily maintained in the laboratory, and they have an accessible nervous system with large, identified neurons that link directly to behavior and can sustain many hours of experimental study. This allows for high precision and reproducibility and makes crayfish a suitable model not just for investigating neurobehavioral questions, but for developing and improving biomedical devices and tools. In the second part of my talk, I will illustrate two projects that are currently ongoing in collaboration with engineering colleagues at UMD. The first one aims to develop nanoparticles that wirelessly activate and record neural activity patterns using microwave signals. Preliminary data using individual neurons of the ex vivo crayfish nerve cord revealed that single action potentials can be robustly recorded by activating microwave signals in a nanoscale magnetic tunnel junction. The future goal of this project is to develop this technique for non-invasive monitoring and modulating of activity in brains of higher complexity. The second project interfaces the crayfish ex vivo ventral nerve cord and innervated hindgut with a multi-sensor 3D printed platform that contains cultured human gut cells and interchangeable colonies of microbiota. The physiological responses to serotonin release from cell cultures will be measured and quantified in crayfish neurons of the central and enteric nervous system and on corresponding hindgut motility with intracellular electrophysiology and motion tracking. The long-term goal is to develop a real-time, high-throughput discovery platform that allows detailed investigation of the cellular processes underlying the gut-brain axis.

MSE Seminar: “A Polymer Brush Approach to Controlling Biological Binding to Surfaces”
2019-10-03 10:45 - 11:45 | Auditorium, LRSM Building, 3231 Walnut Street, Philadelphia, PA, 19104, United States
Polymer brushes are a common feature in many biological surfaces. The ability to rapidly transform a substrate from a hard, structural material to a soft, hydrogel structure over the course of a few tens of nanometers makes polymer brushes elegant materials for tailoring the biology-materials interface. Polymer brushes, because of their surface confinement, are typically stretched from the surface when compared to identical unattached polymer segments and confinement provides them with useful barrier properties. This presentation will discuss recent studies of surface grown polymer brushes, effects of charge on surface properties and brush viability, the use of charged brushes for interaction with biological systems both in terms of directing cell growth and their use for support of cell membrane mimics.
While “grown from” polymer brushes cannot address large surface area applications, the use of block copolymers in place of “grown from” brushes provides most of the benefits of polymer brushes with the ability to coat large area surfaces. Surfaces used for anti-fouling coatings are an example of brush like, large area application. Numerous studies have shown that amphiphilic brush surfaces (with both polar and non-polar groups) provide a broad range of anti-fouling properties. Here we describe new approaches to surface active block copolymers including the use of sequence controlled functional groups to tune surface
properties and surface placement.

Thriving in a Start-Up Ecosystem: Success and Failure in the Life of an Entrepreneur
2019-10-02 18:30 - 20:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
We invite you to join an exclusive event with Penn Engineering alumni who will share their stories on how they have thrived in the startup ecosystem. These alums range from an angel investor in Uber, a serial biotech entrepreneur with several exits, an entrepreneur who has generated over half a billion in licensing deals and one of the top 100 VCs in the world. We hope you can join Dawn Eringis ENG’85 WG’89, Joan Lau ENG’92 W’92, Nihal Mehta C’99 ENG’99, and David Pakman ENG’91, in what promises to be a candid conversation moderated by Professor Vanessa Chan ENG’94.

CBE Seminar: "Thermodynamics of Sequence-defined Polyelectrolyte Complexes”
2019-10-02 15:00 - 16:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract:
Charged polymers known as polyelectrolytes have been studied for decades, however, understanding their physical properties remains a persistent challenge for polymer scientists. This difficulty stems from the intricate interplay between length scales spanning as much as 3-4 orders of magnitude, which has stymied our understanding of a truly important class of polymers; polyelectrolytes are widely used in applications ranging from food additives to paints, and most biopolymers (proteins, DNA, polysaccharides) are also polyelectrolytes. However, the complexity of charged polymers can be harnessed for molecular-level materials design. To demonstrate this, we study a class of polyelectrolyte materials known as complex coacervates. Complex coacervates are aqueous solutions composed of oppositely-charged polyelectrolytes and salt that undergo an associative phase separation process. We use simulation and theory, along with close experimental collaboration, to demonstrate that coacervates are highly sensitive to precise charge patterning. We elucidate the key molecular features that play a large role in coacervate thermodynamics. Building upon these insights, we demonstrate how coacervate phase behavior can be strongly tuned via specific charge sequences. We will show how the physical principles governing the thermodynamics of sequence-defined polyelectrolytes provides the foundation to study coacervate-driven assembly on length scales ranging from monomer-level structure to block copolymer nano-phase separation.

ESE Faculty Hosted Talk: "Deep Learned Optical Multiplexing for Microscopy"
2019-10-02 14:00 - 15:00 | Room 307, Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract: Fourier ptychographic microscopy is a technique that achieves a high space-bandwidth product, i.e. high resolution and high field-of-view. In Fourier ptychographic microscopy, variable illumination patterns are used to collect multiple low-resolution images. These low-resolution images are then computationally combined to create an image with resolution exceeding that of any single image from the microscope. Due to the necessity of acquiring multiple low-resolution images, Fourier ptychographic microscopy has poor temporal resolution. Our aim is to improve temporal resolution in Fourier ptychographic microscopy, achieving single-shot imaging without sacrificing space-bandwidth product. We use physical preprocessing and example-based super-resolution to achieve this goal by trading off generality of the imaging approach.
In example-based super-resolution, the function relating low-resolution images to their high-resolution counterparts is learned from a given dataset. We take the additional step of optimizing the imaging hardware in order to collect more informative low-resolution images. We show that this “physical preprocessing” allows for improved image reconstruction with deep learning in Fourier ptychographic microscopy.

ESE Seminar: "AI and Intelligent IC/Accelerator Design: A Synergistic Approach"
2019-10-01 11:00 - 12:00 | PICS Conference Room 534 – A Wing , 5th Floor, 3401 Walnut Street, Philadelphia, PA, 19104, United States
The recent artificial intelligence (AI) boom has been largely driven by three confluence forces: algorithms, big data, and computing power enabled by modern integrated circuits (ICs) including specialized AI accelerators. In this talk, I will present a synergistic approach on AI and intelligent IC/accelerator designs with two main themes, AI for IC and IC for AI. As the semiconductor technology enters the era of extreme scaling, IC design and manufacturing complexities are becoming extremely high. More intelligent and agile IC design technologies are needed than ever to optimize performance, power, area, manufacturability, reliability, security, etc., and to deliver equivalent scaling to Moore’s Law. I will present some recent results leveraging modern AI and machine learning advancement with domain-specific customizations for agile IC design and manufacturing closure. Meanwhile, customized IC can drastically improve AI performance and energy efficiency by orders of magnitude. I will present the hardware/software co-design for energy-efficient neural networks. The bidirectional reinforcement of AI and IC technologies holds great potential to significantly advance the state-of-the-art of each other.

Tedori-Callinan Lecture: "Isogeometric Analysis"
2019-10-01 10:30 - 12:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
The vision of Isogeometric Analysis was first presented in a paper published October 1, 2005 [1]. Since then it has become a focus of research within both the fields of Finite Element Analysis (FEA) and Computer Aided Design (CAD) and is rapidly becoming a mainstream analysis methodology and a new paradigm for geometric design [2]. The key concept utilized in the technical approach is the development of a new foundation for FEA, based on rich geometric descriptions originating in CAD, resulting in a single geometric model that serves as a basis for both design and analysis.
In this overview, I will describe some areas in which progress has been made in developing improved methodologies to efficiently solve problems that have been at the very least difficult, if not impossible, within traditional FEA. I will also describe current areas of intense activity and areas where problems remain open, representing both challenges and opportunities for future research (see, e.g., [3,4]).
REFERENCES
[1] T.J.R. Hughes, J.A. Cottrell and Y. Bazilevs, Isogeometric Analysis: CAD, Finite Elements, NURBS, Exact Geometry and Mesh Refinement, Computer Methods in Applied Mechanics and Engineering, 194, (2005) 4135-4195.
[2] J.A. Cottrell, T.J.R. Hughes and Y. Bazilevs, Isogeometric Analysis: Toward Integration of CAD and FEA, Wiley, Chichester, U.K., 2009.
[3] Special Issue on Isogeometric Analysis, (eds. T.J.R. Hughes, J.T. Oden and M. Papadrakakis), Computer Methods in Applied Mechanics and Engineering, 284, (1 February 2015), 1-1182.
[4] Special Issue on Isogeometric Analysis: Progress and Challenges, (eds. T.J.R. Hughes, J.T. Oden and M. Papadrakakis), Computer Methods in Applied Mechanics and Engineering, 316, (1 April 2017), 1-1270.

MSE Seminar: “Topology and Quantum Matter: From Axions to Spintronics”
2019-09-26 10:45 - 11:45 | Auditorium, LRSM Building, 3231 Walnut Street, Philadelphia, PA, 19104, United States
The confluence of fundamental symmetries and spin-orbit coupling is known to produce emergent electronic states in crystalline solids that are accurately described using the language of topology. This talk provides an overview of this relatively young field of research, showing how the synthesis and study of topological quantum matter yields a playground for both exotic pursuits at millikelvin temperatures (such as the realization of axion electrodynamics in condensed matter [3]) and pragmatic technologies that work under ambient conditions (such as spintronic devices).

CBE Seminar: "Protein-integrated Electronics: From Molecules to Machines”
2019-09-25 15:00 - 16:00 | Wu and Chen Auditorium (Room 101), Levine Hall, 3330 Walnut Street, Philadelphia, PA, 19104, United States
Abstract:
We are developing chemo-mechatronic systems, structures, and machines that can transduce signals between the chemical, mechanical, and electrical domains to produce intelligent behaviors in response to an external stimuli. Inspired by systems spanning from how tissues build themselves to how animals camouflage, I will discuss our molecular-level approach to building new materials that can produce tailorable and reversible transformations in response to specific chemical inputs for applications ranging from bio-photonic devices to implantable electronics.

Penn Engineering's NSF Fellowship Workshop
2019-09-24 18:00 - 19:00 | Heilmeier Hall (Room 100), Towne Building, 220 South 33rd Street, Philadelphia, PA, 19104, United States
Penn Engineering is holding a workshop for students interested in applying for the 2020 National Science Foundation Graduate Research Fellowship (NSFGRF) .
The goal of this workshop is to discuss strategies for submitting a strong application, as well as to connect applicants with mentors to help guide applicants through the process.
This event will involve a panel discussion with successful NSF GRF awardees from SEAS and will be moderated by Penn Engineering faculty members. All 1st and 2nd year PhD scholars eligible for submitting an NSF GRF fellowship application are invited to attend.
