Rensselaer Polytechnic Research Articles

The Research Data Alliance: Benefits and Challenges of Building a Community Organization

The Research Data Alliance (RDA) is a community-driven organization dedicated to the development and use of technical, social, and community infrastructure promoting data sharing and data-driven exploration. RDA is particularly important for the global academic community where research infrastructure is often ad hoc, may have a short shelf-life, and hard to fund.At its launch in 2013, RDA struck a chord. Since then, RDA has attracted more than 9400 members from 130-plus countries and developed infrastructure used by groups all over the world. One of its founders is Francine Berman (FB), 2019–2020 Radcliffe Fellow at Harvard and the Edward P. Hamilton Distinguished Professor of Computer Science at Rensselaer Polytechnic Institute. Berman served as co-chair of RDA’s leadership council and chair of the U.S. region of RDA (RDA/US) for the first 6 years of RDA’s growth. Her leadership and organizational experience in developing and operating national-scale cyberinfrastructure (she is former director of the San Diego Supercomputer Center) and her broad community contributions have helped drive the success of RDA.In this piece, Berman is interviewed by Mercè Crosas, Harvard University’s Research Data Officer with the Chief Information Officer’s leadership team and leader of Dataverse. Berman and Crosas met through RDA and both have deep knowledge of the benefits and challenges of running a community-focused organization. They share some of those insights in the conversation below. More information, including specifics on the RDA community and RDA’s ‘origin story,’ can be found here <https://www.rd-alliance.org/sites/default/files/attachment/RDA%20RETROSPECTIVE%20FINAL%20-%20HDSR.pdf> .

Invited Lecture 8: Innovation and Exponential Technologies in the Era of COVID 19

Brief Biosketch Prof. Mary Hrachoohi Boghosian did her PhD in “Physics of Magnetic Materials” from the University of London, Imperial College of Science and Technology, London, England, and MBA in “Innovation, Technology Planning and Management” from the Rensselaer Polytechnic Institute (RPI), School of Management and Technology, Troy, New York. She is working as Adjunct Professor at the American University of Armenia (AUA) and the California State University of Los Angeles (USA). She is also a visiting professor at the Yerevan State University, School of Journalism initiating and teaching a postgraduate-level course on the “Essentials of Creative Thinking”. She spent 16 years working for NASA and the Aerospace Companies leading NASA projects and studies as well as developing the first-ever cost estimation methodology for costing very small satellites. Dr Boghosian is the author of more than forty publications and two inventions on space-related sensors and actuators. She is a recipient of several NASA technology achievement awards. In highly competitive economies, technology advancements move at an exponential pace leading to rapid change in innovation. Covid-19 has reshaped the global scientific and technological community through urgency for sharing information in research and technology development. COVID 19 has also shaped business commercialization and consumer behaviour allowing faster response and new infrastructure for technology and business development. In the midst of all this, exponential technologies supported by disruptive digitization allow companies to create their own innovation processes allowing cross industries and break down barriers. We will discuss the exponential technologies and the disruptive digitization process leading to new innovations and digital society and economy.

Patents targeting the Warburg effect for cancer therapy: an interview with William P Katt.

Dr William Katt is a multidisciplinary scientist with particular focus in computational, synthetic and biological chemistry. He obtained his undergraduate degree at Rensselaer Polytechnic Institute and performed his graduate studies at Yale University, where he focused on designing small-molecule inhibitors of the Rho/Rho GEF interaction. Following those studies, Dr Katt accepted a fellowship from the American Cancer Society which funded his work at Cornell University, where he investigated small-molecule inhibitors of the enzyme glutaminase, a key player in cancer metabolism. Today, Dr Katt is a research associate at Cornell and maintains a number of collaborations with researchers across the nation examining glutaminase, cancer stem cells, nano-therapeutics and more, with the goal of developing therapeutic approaches that will eventually help patients in the clinic.

Reflections on the Ingredients for Success in AI Research: An Interview with Arvind Gupta

This article contains the observations of Arvind Gupta, who has over 22 years of experience in leadership, policy, and entrepreneurial roles, in both the Silicon Valley and India. Gupta was recently interviewed about the factors that could influence successful artificial intelligence research. At the time of the interview, Gupta was the chief executive officer of MyGov, India. During our interview, he shared with the editorial team his perspectives on investing in artificial intelligence innovations for business and society, in India. The interviewers included members of the special track edito­rial team from IBM (Biplav Srivastava, Daby Sow, and Ching-Hua Chen) and Rensselaer Polytechnic Institute (Oshani Seneviratne).

Reflections on Successful Research in Artificial Intelligence: An Interview with Yolanda Gil

This article contains the observations of Yolanda Gil, director of knowledge technologies and research professor at the Information Sciences Institute of the University of Southern California, USA, and president of Association for Advancement of Artificial Intelligence who was recently interviewed about the factors that could influence successful AI research. The editorial team interviewers included members of the special track editorial team from IBM Research (Biplav Srivastava, Ching-Hua Chen) and Rensselaer Polytechnic Institute (Oshani Seneviratne).

Polymer provides extended release of estrogen

Few people recover completely from spinal cord injuries, and the ones that do tend to be women. This sex difference has led to interest in the use of estrogen, which has been shown to protect neurons and help them grow, as a treatment for spinal cord injury. The challenge for this approach is finding a way to avoid side effects of high estrogen doses by delivering the hormone at low doses over an extended period. Researchers have previously used polymeric nanoparticles to deliver the hormone. But such materials sustain delivery for only a few days or weeks. Now, Ryan J. Gilbert, Edmund F. Palermo, and coworkers at Rensselaer Polytechnic Institute have synthesized a polymer that can release estrogen over much longer periods, perhaps even years. Instead of mixing estrogen with an inert carrier polymer, they incorporate it as part of the polymer (Nat. Commun. 2019, DOI: 10.1038/s41467-019-12835-w). Their material is

Numerical simulation study on the flow and heat transfer characteristics of sub-cooled boiling in vertical round and flattened tubes

Sub-cooled boiling is crucial in dominating the operation performance in several engineering processes. In spite of the experimental investigations conducted in the previous reports, the mechanism of how tube shape affects the heat transfer is still in vagueness. Here, a simulation study on the sub-cooled water flow boiling in tubes of various shapes is performed by adopting the RPI (Rensselaer Polytechnic Institute) model to elucidate the structural effect on the hydraulic and thermal performance, including the average vapor volume fraction and pressure drop. The results demonstrate that for tubes with aspect ratio (AR) ranging from 0 to 5 the heat transfer performance varies greatly, among which the testing tube with AR = 3 exhibits the supreme. The heat transfer coefficient and pressure drop show an around 20% and 7% enhancement, respectively, when the tube AR increases from 0 to 3. Our results show: for these geometric and physical models, when aspect ratio (AR = 0, 1, 3 and 5) of flattened tube is equal to 3 which has the best heat transfer performance and then tends to be stable. For other factors, the heat transfer coefficient enhances by increasing heat flux (395.8 kW/m2, 475 kW/m2 and 570.0 kW/m2), mass flux (900, 990 and 1080 kg/(m2·s)). Heat transfer coefficient increases about 20%, pressure drop augments about 7% when the flattened tube’s AR increases from 0 to 3.

Numerical investigation on the nucleate pool boiling heat transfer of R134a outside the plain tube

In the present work, a numerical method is utilized to simulate the nucleate pool boiling of R134a outside the horizontal plain tube. Eulerian multiphase model integrated with Rensselaer Polytechnic Institute (RPI) nucleate boiling model is adopted. The nucleate pool boiling is numerically investigated at the heat flux of 20–80 kW/m2 and saturation temperatures of 279 and 299.7 K. By analyzing the experimental results, a modified correlation of active nucleation site density is proposed. The numerical results based on the modified correlation agree well with the experimental data of the pool boiling heat transfer outside the plain tube. According to the simulation of azimuthal variations of temperature around the tube, it is found that the region between 90° and 130° has the best heat transfer performance for its high velocity and turbulence. The maximum temperature appears at the upper of the tube because the velocity and turbulence intensity at this region are lower. The investigation helps to explain the phenomena and observed facts in the experiment.

George P. Gross

George P. Gross, 94, died on Oct. 13, 2018, in Chatham, New Jersey. “George was a research associate for Exxon for more than 30 years, focusing on cleaner-burning fuels and receiving patents for his work. He was a US Navy veteran of World War II and served as a navigation officer aboard the USS Topeka. In his youth, George was active as a Boy Scout, attending the first National Jamboree and attaining the Eagle Scout rank. He remained active in Scouting with his sons, as a leader in both Troops 71 and 77 in Westfield, New Jersey. As a Scout leader, he taught young men to become active citizens who grew up to contribute to their community and beyond. George had a lifelong passion for nature and outdoor activities such as bird watching and hiking.”—family of George Gross Most recent title: Research associate, Exxon Education: PhD, chemistry, Rensselaer Polytechnic Institute,

Experimental measurements of isothermal reactivity coefficient and temperature-dependent reactivity changes with associated uncertainty evaluations

The low power Reactor Critical Facility (RCF) at Rensselaer Polytechnic Institute has recently been utilized to design and perform low-power temperature dependent experiments. The experiments include determination of isothermal excess reactivity and reactivity coefficient at different temperatures and measurements of time-dependent reactivity change with system temperature change. The above-mentioned experiments have produced significant quantities of data, and numerous post-processing steps are needed in order to make the data useful for computational model validation. One important step toward providing the data as an accurate and high-fidelity experiment benchmark for modern code validation is to develop in-depth experimental uncertainty quantification. In this paper, we analyze in particular two types of reactor physics experiments driven by the change in system temperature within a small temperature range. Uncertainty quantification includes separately derived experimental errors for both independent (temperature) and dependent (reactivity) variables, and an iterative weighted least squares approach is used to combine them into the equivalent uncertainty in reactivity. The results of the experiments show the negative effects of the system temperature on reactor reactivity due to combined effects of the Doppler broadening in the fuel, the S(α,β) thermal scattering physics and the decrease in water density. The low uncertainty values obtained for the reactor isothermal excess reactivity (<0.10 cents), the isothermal reactivity coefficient (<0.01 cents/°C), and the time-dependent reactivity change with system temperature increase (<0.16 cents) show that these experiments can be reliably used as benchmarks for code validation. The iterative method adapted in this work for combining temperature and reactivity uncertainties can be used to analyze similar temperature-dependent reactivity benchmark experiments.

Eulerian–Eulerian multi-phase RPI modeling of turbulent forced convective of boiling flow inside the tube with porous medium

PurposeThe purpose of this study is simulation the flow boiling inside a tube in the turbulent flow regime for investigating the effect of using a porous medium in the boiling procedure.Design/methodology/approachTo ensure the accuracy of the obtained numerical results, the presented results have been compared with the experimental results, and proper coincidence has been achieved. In this study, the phase change phenomenon of boiling has been modeled by using the Eulerian–Eulerian multi-phase Rensselaer Polytechnic Institute (RPI) wall boiling model.FindingsThe obtained results indicate using a porous medium in boiling process is very effective in a way that by using a porous medium inside the tub, the location of changing the liquid to the vapor and the creation of bubbles, changes. By increasing the thermal conductivity of porous medium, the onset of phase changing postpones, which causes the enhancement of heat transfer from the wall to the fluid. Generally, it can be said that using a porous medium in boiling flows, especially in flow with high Reynolds numbers, has a positive effect on heat transfer enhancement. Also, the obtained results revealed that by increasing Reynolds number, the created vapor phase along the tube decreases and by increasing Reynolds number, the Nusselt number enhances.Originality/valueIn present research, by using the computational fluid dynamics, the effect of using a porous medium in the forced boiling of water flow inside a tube has been investigated. The fluid boiling inside the tube has been simulated by using the multi-phase Eulerian RPI wall boiling model, and the effect of thermal conductivity of a porous medium and the Reynolds number on the flow properties, heat transfer and boiling procedure have been investigated.

Half a century of Lighting Research & Technology: A bibliometric review

Lighting Research &amp; Technology (LRT) is an influential journal in the field of light and lighting dating back to 1969. To celebrate its 50th birthday, the current study explored its bibliometric characteristics and mapped the bibliographic information graphically through VOSviewer software. This analysis found that the number of papers has steadily increased during recent years. The most productive and cited country was the United Kingdom. The most productive and cited institution was Rensselaer Polytechnic Institute. The most prolific author was Steve Fotios and the most cited author was Mark Rea. The journal most cited together with LRT was Leukos. LRT has become more and more international and interdisciplinary over the last five decades. Suggestions for the development of LRT are provided. Develpoments over the last 50 years have turned LRT into one of leading journals in the light and lighting field, one which has a bright future.

Effects of vibration on pool boiling heat transfer from a vertically aligned array of heated tubes

In the present study, the use of mechanical vibration for the enhancement of pool boiling heat transfer is evaluated theoretically. For this purpose, a vertical array of vibrating circular tubes is considered. The array is submerged in a pool of water under atmospheric conditions and electrically heated for boiling to occur on the tube surfaces. To model this phase-change phenomenon, a two-fluid formulation is employed and accompanied by the Rensselaer Polytechnic Institute (RPI) model to estimate the boiling heat flux on a solid surface. A comprehensive parametric study is undertaken to investigate the effects of the amplitude and frequency of vibration, the magnitude of the heat flux, and the pitch-to-diameter ratio of the array on pool boiling heat transfer in the presence of mechanical vibration. An increase of up to 90% in the heat transfer rate is achieved within the simulated operating conditions.

Oxides of Manganese As Efficient Bifunctional Electrocatalysts

The electrolysis of water, or water splitting reaction is one of the cleanest ways of producing hydrogen and oxygen gas for fuel. Electrochemical devices employing these reactions include regenerative fuel cells and rechargeable metal-air batteries, which have the highest theoretical energy density. Considerable efforts have been dedicated towards improving the energy conversion efficiency of these devices. However, the single main obstacle for achieving this has been the lack of suitable bifunctional oxygen electrocatalysts that show simultaneous high activity for both oxygen reduction (ORR) and oxygen evolution (OER) reactions during charge/discharge cycles. The overpotential and slow kinetics of oxygen reactions are limiting parameters in the advancement of electrochemical storage devices. Taking inspiration from nature’s photosynthetic process that uses a Mn4O4Ca cluster in photosystem II to catalyze water splitting, we studied the efficiency of various phases of manganese oxide (MnOx) as electrocatalysts for OER and ORR process, including the role of defects on bifunctionality. Cyclic voltammetry was used to prove that Mn2O3 is a bifunctional catalyst by showing high activity for OER and ORR. Next, in-situ UV-Vis absorbance spectroscopy was conducted to track changes in the surface oxidation state as a result of occurring reactions. Finally, we use electrochemical quartz crystal microbalance to track ion intercalation into the material. Results from these studies were used to obtain a structure-defect-function correlation that can improve the design of electrocatalysts with bifunctional properties. Acknowledgements: The authors would like to thank Rensselaer Polytechnic Institute (RPI) and National Science Foundation, CBET award (No: 1511733), for the partial financial support and Nicholas Smieszek for his assistance with the preparation of this manuscript. I.R, and Q.W also gratefully acknowledge the partial support of Howard P. Isermann fellowship provided by the Department of Chemical and Biological Engineering at RPI.

Influences of operator head posture and protective eyewear on eye lens doses in interventional radiology: A Monte Carlo Study.

To quantify the effects of operator head posture and different types of protective eyewear on the eye lens dose to operators in interventional radiology (IR). A deformable computational human phantom, Rensselaer Polytechnic Institute (RPI) Adult Male, consisting of a high-resolution eye model, was used to simulate a radiologist who is performing an interventional radiology procedure. The radiologist phantom was deformed to a set of different head postures. Three different protective eyewear models were incorporated into the posture-deformed radiologist phantom. The eye lens dose of the radiologist was calculated using the Monte Carlo code, MCNP. Effects of the radiologist's head posture and different types of protective eyewear on eye lens doses were studied. The relationship between efficacy of protective eyewear and the radiologist's head posture was investigated. Effects of other parameters on efficacy of protective eyewear were also studied, including the angular position of the radiologist, the gap between the eyewear and the face of the radiologist, and the lead equivalent thickness. The dose to both lenses decreased by 80% as the head posture moved from looking downward to looking upward. Sports wrap glasses were found to reduce doses further than the other two studied models. The efficacy of eyewear was found to be related to radiologist's head posture as well. When the radiologist was looking up, the protective eyewear almost provided no protection to both lenses. Other factors such as the face-to-eyewear distance and the lead equivalent thickness were also found to have an impact on the efficacy of protective eyewear. The dose reduction factor (DRF), defined as the ratio of the dose to the lens without protection to that with protection, decreased from 4.25 to 1.07 as the face-to-eyewear distance increased. The DRF almost doubled when the lead equivalent thickness increased from 0.07 to 0.35mm. However, further increase in lead equivalent thickness showed little improvement in dose reduction. The radiologist's head posture has a significant influence on the eye lens dose in IR. Sports wrap protective eyewear which conforms to the curve of the face is essential for the radiation protection of the eye lens. However, the radiologist's head posture and other exposure parameters should be considered when evaluating the protection of the radiologist's eyes.

Three-dimensional numerical study of direct steam generation in vertical tubes receiving concentrated solar radiation

Concentrated solar thermal energy is a good alternative to mitigate the environmental impacts generated by the growing use of energy. There are several commercial solar power tower plants in the world operating with direct steam generation. These plants operate with cavity-type and external tubular receivers. The conventional tubular receivers consist of a set of vertical circular tubes through which the working fluid circulates. This study is focused to analyze in detail the direct steam generation in a vertical tube receiving concentrated solar radiation. The mathematical model is based on the equations of continuity, momentum and energy for each phase. The modified model of Rensselaer Polytechnic Institute was used for the conditions of critical heat flux coupled to a Eulerian two fluid model. In the modified model of Rensselaer Polytechnic Institute, the total heat flux is divided into four components from the wall to the liquid: (a) liquid-phase convective heat flux, (b) heat transfer due to quenching, (c) heat flux due to evaporation and (d) convective heat flux of the vapor phase. The mathematical model was solved with a computational fluid dynamics software. The results were validated with experimental data reported in the literature and a parametric study was carried out to determinate the effect of the mass flux and heat flux incident on the wall, on: the steam quality, the volumetric fraction, the enthalpies and temperatures of liquid and steam. The reduction of mass flux by 44% increased the output mass flow of steam 4.28 times, whereas the increase of concentrated solar flux by 40% increased the output mass flow of steam 4 times.

Centrifuge tests on liquefaction potential and slope stability of mine tailings

Several factors have led to the extended need for investigation of the static and dynamic behaviour of mine tailings and include the rising generation and surface storage of mine waste, its frequent use as a construction material for the retaining structures and the relatively high rate of associated failures, with seismic liquefaction being a rather common cause. In this experimental study, dynamic response and surface slope stability of a layered mine tailings deposit were examined by means of four centrifuge tests performed at the Center for Earthquake Engineering Simulation (Rensselaer Polytechnic Institute). The material under study was fine copper–gold tailings and the varying parameters were average degree of consolidation prior to dynamic loading and base acceleration amplitude. The material was found to be liquefiable and its performance in terms of acceleration, shear strain, slope stability, residual lateral deformation, pore-pressure build-up and liquefied depth was somewhat dependent on the aforementioned parameters. The response of the deposits changed with increasing depth and effective stress, which made centrifuge testing highly advantageous.

Reaction: Precision Macromolecules for Self-Assembly

Wei Zhang received his BS degree from Peking University and PhD degree in polymer science from the University of Akron (UA). He is now a postdoc at Harvard Medical School. Xuehui Dong received his BS degree at the University of Science and Technology of China and PhD degree in polymer science from UA. After completing postdoctoral research at the Massachusetts Institute of Technology, he joined the South China Advanced Institute for Soft Matter Science and Technology (AISMST) as a professor. Stephen Z.D. Cheng received his PhD degree from Rensselaer Polytechnic Institute. He has been at UA for his entire career and also serves as dean for AISMST at the South China University of Technology. He has received a number of awards and has been a member of the US National Academic of Engineering since 2008. His research interests span condensed states in polymers, liquid crystals, and hybrid systems.

Reaction: Size Distribution in Olefin Block Copolymers: Not Bad at All

Hongyu Chen completed his PhD in macromolecular science at Case Western Reserve University in 2010. He is a fellow of the Dow Chemical Company, where he focuses on developing new products. He is also a fellow of the American Physical Society and American Chemical Society. Valeriy Ginzburg completed his PhD in polymer physics at the Moscow Institute of Physics and Technology in 1992. He is a senior scientist at the Dow Chemical Company and a fellow of the American Physical Society.

Tantalum, Titanium, and Zirconium Neutron Total Cross-Section Measurements from 0.4 to 25 MeV

The electron linear accelerator housed in the Gaerttner Linear Accelerator Center at Rensselaer Polytechnic Institute was used to generate a pulsed neutron source to measure the neutron total cross section of tantalum, titanium, and zirconium from 0.4 to 25 MeV. Neutron transmission measurements were made using the time-of-flight method with neutron flight paths of approximately 100 and 250 m. The long flight paths combined with narrow neutron pulse widths, fast detector responses, fast electronics, and data collection system provide good energy resolution for the measurements. A high signal-to-background ratio through much of the energy range combined with low statistical errors resulted in low uncertainties on cross sections.The results are presented and compared with the major nuclear data evaluations. Each measurement identifies regions where the neutron total cross sections could be reevaluated. The total cross-section measurements presented here can help nuclear data evaluators improve neutron total cross-section data in future evaluations.