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A Framework For New Generation Transportation Simulation, Daiheng Ni

Daiheng Ni

This paper discussed the evolution and future trend of simulation in general domain and in transportation. Some challenges facing transportation modeling and simulation were identified. As an effort to address these challenges, a framework of new generation transportation simulation was developed. The framework is envisioned to be multi- scale in resolution, parallel in execution, and driven by ob- jects. The paper further discussed strategies of transporta- tion simulation at a nanoscopic level which offers a level of modeling detail beyond the state-of-the-art.

Characterization Of Manganese Oxide Coated Filter Media, Joseph Goodwill

Environmental & Water Resources Engineering Masters Projects

Abstract Several methods for removal of soluble maugauese from drinking water exist. One of these options involves adsorption of the maugauese onto Mn oxide coated filter media. Dissolved maugauese (Mn(H)) is adsorbed to sites on the Mn oxide coating aud then oxidized by free chlorine, thus regenerating the media sites for further Mn adsorption. This method has been successfully used by numerous water treatment plauts, decreasing Mn levels to below treatment goals. A disadvautage to this method is the use of chlorine prior to filtration, which cau lead to increased levels of disinfection by-products as compared to post-filter chlorination. Nine …

Impact Of Chloramines On Disinfection By-Products In Selected Surface Water Supplies, Allan P. Briggs

Environmental & Water Resources Engineering Masters Projects

Aquarion Water Company (AWC) of Connecticut owns and operates the Warner, Stamford and Dean's Mill drinking water treatment plants among several other facilities. Bench-scale experiments were conducted to evaluate the impact of secondary disinfection with chloramines on disinfectant by-products (DBP) for these three supplies. The goal was to determine if a significant decrease in DBP formation could be achieved. The final Stage 2 Disinfectants and Disinfection By-Products (DDBP) Rule has prompted A WC to investigate strategies that can help decrease DBP formation in their finished and distributed water. The Stage 2 DDPB Rule regulates two classes of DBPs, the four …

The Relationship Between Pre-Filter Chlorine Addition And Enhanced Disinfection Byproduct Formation, Melissa Brown

Environmental & Water Resources Engineering Masters Projects

In this work, the issue of how pre-filter chlorination of drinking water causes an increase in disinfection byproduct (DBP) formation is examined. Chlorination and granular media filtration are two widely used practices in drinking water treatment. It is also common to apply chlorine ahead of the filters. However, this has been shown to elevate disinfection byproducts (DBP) levels. Experiments were performed at full- and bench-scale using filter influent and effluent from working filters and several anthracite/sand filter columns operated in parallel. The filter influent for the bench-scale experiments was clarified water from the Warner Water Treatment Plant operated by the …

Performance Evaluation Of Appropriate In-Home Drinking Water Treatment Options For Developing Countries, Bree Carlson

Environmental & Water Resources Engineering Masters Projects

Globally, over one billion people do not have access to safe drinking water. The majority of these people live in developing nations, where large-scale drinking water treatment projects may not provide a viable solution because of a lack of skilled laborers, consistent and reliable electricity, materials, sufficient economic capital, and/or fuel sources. Appropriate non-conventional drinking water treatment technologies may provide a solution to these problems, particularly if such technologies are composed of materials readily accessible to the population. Three treatment technologies whose materials are easily acquired throughout the developed and developing world are sari filtration, solar disinfection, and citrus fruit …

Application Of Microbial Source Tracking To Separate Microbial Sources To A Tributary Of The Wachusett Reservoir, Michael N. Tache

Environmental & Water Resources Engineering Masters Projects

Surface waters used as sources of drinking water can be at risk for pathogen contamination from non-point source pollution. Non-point source pollution is a problem because it can be difficult to detect and quantify. Source water protection is a tool to protect public health by maintaining and improving source water quality. The Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR), which aims to improve the control of Cryptosporidium, recognizes watershed protection programs as part of both Cryptosporidium and virus removal requirements. Microbial source tracking (MST) is a tool that is currently being developed to aid in source water protection. …

The Suitability Of Coliphage As An Indicator Of Potential Fecal Contamination In Groundwater Systems, Keith G. Dewar

Environmental & Water Resources Engineering Masters Projects

Over the years aquifers have been considered a clean source of drinking water as the soil acts as a natural filter. It.has been realized that groundwater used as a source of drinking water can be subject to fecal contamination through a number of various sources. With almost half of the United States national domestic water supply originatng from groundwater, a system of monitoring for contamination should be implemented to ensure public health and safety. Monitoring water to assess its microbial safety has long relied on the detection of indicator microorganisms, total and fecal coliforms in particular. Coliform bacteria has exhibited …

Towards Defect-Tolerant Nanoscale Architectures, C. Andras Moritz, Teng Wang

C. Andras Moritz

Nanoscale computing systems show great potential but at the same time introduce new challenges not encountered in the world of conventional CMOS designs and manufacturing. For example, these systems need to work around layout and doping constraints resulting from unconventional bottom-up selfassembly, and need to cope with high manufacturing defect rates and transient faults. Unfortunately, most conventional defecttolerance techniques are not directly applicable in nanoscale systems because they have been designed for very small defect rates. In this paper, we explore built-in defect-tolerance techniques on 2-D semiconductor nanowire (NW) arrays to make designs self-healing. Our approach combines circuit and systemlevel …

Study And Characterization Of Tobacco Mosaic Virus Head-To-Tail Assembly Assisted By Aniline Polymerization, Zhongwei Niu, Michael Bruckman, Venkata S. Kotakadi, Jinbo He, Todd S. Emrick, Thomas P. Russell, Lin Yang, Qian Wang

Todd S. Emrick

One-dimensional composite nanofibres with narrow dispersity, high aspect ratio and high processibility have been fabricated by head-to-tail self-assembly of rod-like tobacco mosaic virus assisted by aniline polymerization, which can promote many potential applications including electronics, optics, sensing and biomedical engineering.

Stabilization Of Α-Chymotrypsin At Air–Water Interface Through Surface Binding To Gold Nanoparticle Scaffolds, Brian J. Jordan, Rui Hong, Basar Gider, Jason Hill, Todd S. Emrick, Vincent M. Rotello

Todd S. Emrick

Gold nanoparticles stabilize chymotrypsin (ChT) against denaturation at the air–water interface through catenation and preferential localization of the nanoparticles at the air–water interface with concomitant decrease in interfacial energy.

In Situ Observation Of Place Exchange Reactions Of Gold Nanoparticles. Correlation Of Monolayer Structure And Stability, Rui Hong, Joseph M. Fernández, Hiroshi Nakade, Rochelle Arvizo, Todd S. Emrick, Vincent M. Rotello

Todd S. Emrick

Place exchange reactions were studied using dye displacement: subtle changes in ligand structure greatly affected both the rate of displacement and the stability of the monolayer.

Kinetic Modeling Of Slurry Propylene Polymerization Using Rac-Et(Ind)2zrcl2/Mao, Ramon A. Gonzalez-Ruiz, Bernabe Quevedo-Sanchez, Robert L. Laurence, Michael A. Henson, E. Bryan Coughlin

Michael A Henson

The slurry homopolymerization of propylene catalyzed by the isospecific metallocene rac-Et(Ind)2ZrCl2/MAO was investigated using a semi-batch reactor. A full factorial design with three temperatures (50, 65 and 75°C) and four monomer partial pressure (1.5, 2.5, 3.2, and 3.8 atm) was performed. Analysis by 1H NMR revealed the formation of vinylidene, cis-2-butenyl and 4-butenyl end-groups. A kinetic model based on a coordination-insertion mechanism was developed to predict instantaneous reaction rate, molecular weights and polymer chain ends. The kinetic rate constants were estimated using a systematic optimization strategy. The model predicts that the insertion of the first propylene molecule is rate limiting …

Proposal To The Ethics Education In Science And Engineering Program, National Science Foundation: Role-Play Scenarios For Teaching Responsible Conduct Of Research, Michael C. Loui, C. K. Gunsalus

Ethics in Science and Engineering National Clearinghouse

We propose to develop and assess role-play scenarios to teach central topics in the responsible conduct of research (RCR) to graduate students in science and engineering. Together the scenarios will cover plagiarism, authorship, conflict of interest, interpersonal conflicts in mentoring, and concerns about compliance with research regulations on human participants in research, animal subjects, or hazardous substances. Two scenarios will present potential whistleblowing situations.

Intellectual merit: Few previous studies have carefully assessed the effectiveness of role-play in teaching ethics. We will conduct a rigorous, systematic assessment of role-play, using multiple methods, with a diverse group of graduate students. We will …

Spontaneous Formation Of Stable Aligned Wrinkling Patterns, Edwin P. Chan, Alfred Crosby

Alfred Crosby

We introduce a new methodology to produce aligned, or patterned, surface wrinkles on a soft elastomer sans topography. The surface buckles orient through the manipulation of the local stress distributions, which we control by defining specific regions of local differences in the elastic moduli of the material.

Origin Of The Formation Of The 4-Butenyl End Group In Zirconocene-Catalyzed Propylene Polymerization, Bernabe Quevedo-Sanchez, Michael A. Henson, E. Bryan Coughlin

Michael A Henson

It has been proposed that the 4-butenyl end group in polypropylene is formed by isomerization of the 2-butenyl end group. Prior experimental evidence has shown that the isomerization is not produced thermally or upon an acidic treatment during the workup or analysis of the polymer. We postulate that the production of the 4-butenyl end group by isomerization might be catalyzed by a zirconocene hydride complex that forms during the β-hydride elimination reaction. The isomerization of a preformed olefinic-end-group isotactic polypropylene with a well-known transition-metal hydride shows the disappearance of the 2-butenyl end group concomitant with the appearance of the 4-butenyl …

Transient Dynamics And Structure Of Optimal Excitations In Thermocapillary Spreading: Precursor Film Model, Jm Davis, De Kataoka, Sm Troian

Jeffrey M. Davis

Linearized modal stability theory has shown that the thermocapillary spreading of a liquid film on a homogeneous, completely wetting surface can produce a rivulet instability at the advancing front due to formation of a capillary ridge. Mechanisms that drain fluid from the ridge can stabilize the flow against rivulet formation. Numerical predictions from this analysis for the film speed, shape, and most unstable wavelength agree remarkably well with experimental measurements even though the linearized disturbance operator is non-normal, which allows transient growth of perturbations. Our previous studies using a more generalized nonmodal stability analysis for contact lines models describing partially …

Synthesis Of Transportation Fuels From Biomass:  Chemistry, Catalysts, And Engineering, George W. Huber, S. Iborra, A. Corma

George W. Huber

No abstract provided.

Theoretical Analysis Of The Effect Of Insoluble Surfactant On The Dip Coating Of Chemically Micropatterned Surfaces, N Tiwari, Jm Davis

Jeffrey M. Davis

Microfluidic flow on chemically heterogeneous surfaces is a useful technique with applications ranging from selective material deposition to the self-assembly of nanostructures. The recent theoretical analysis by Davis [Phys. Fluids 17, 038101 (2005)] of the dip coating of a pure fluid onto vertical, wetting stripes surrounded by nonwetting regions quantified the experimentally observed deviations from the classical Landau-Levich result due to lateral confinement of the fluid by chemical surface patterning. In this present work, the analysis of dip coating of these heterogeneous surfaces is extended to a liquid containing an insoluble surfactant. Using matched asymptotic expansions based on lubrication theory …

Wetting Of Rings On A Nanopatterned Surface: A Lattice Model Study, Peter A. Monson, Fabien Porcheron

Peter A. Monson

We perform mean-field density functional theory calculations on a lattice model to study the wetting of a solid substrate decorated with a ring pattern of nanoscale dimensions. We have found three different liquid morphologies on the substrate: a ring morphology where the liquid covers the pattern, a bulge morphology where a droplet is forming on one side of the ring, and a morphology where the liquid forms a cap spanning the nonwetting disk inside the pattern. We investigate the relative stability of these morphologies as a function of the ring size, wall-fluid interaction, and temperature. The results found are in …

Lyotropic Columnar Liquid Crystals Based On Polycatenar 1h-Imidazole Amphiphiles And Their Assembly Into Bundles At The Surface Of Silicon, Sang Hyuk Seo, Gregory N. Tew, Ji Young Chang

Gregory N. Tew

Polycatenar 1H-imidazole amphiphiles, consisting of a 1H-imidazole head connected through a benzene ring to a trialkyloxyphenyl tail, were synthesized and their self-assembling properties investigated. The 1H NMR and fluorescence spectroscopy studies showed that in nonpolar solvents, the amphiphiles formed reverse micelles in which the hydrophilic imidazole heads aggregated inside the micelles through intermolecular hydrogen bonding and the nonpolar alkyl chains were located at the periphery of the micelles. In concentrated solutions, they formed lyotropic liquid crystals having columnar hexagonal structures. The molecules were arranged in a disk via hydrogen bonding between successive imidazole moieties. When dilute solutions of the amphiphiles …

Insight Into The Periodicity Of Schallamach Waves In Soft Material Friction, Charles J. Rand, Alfred Crosby

Alfred Crosby

A dominant mechanism in friction of soft materialinterfaces is the onset and propagation of Schallamach waves. Schallamach waves are “tunnels” of air that provide relative displacement between the slider and the substrate rather than the instantaneous interfacial failure involved with stick-slip. Here, through model experiments and analysis, the authors present a fundamental relationship between the periodicity of Schallamach waves(λ) and the ratio of interfacialadhesion(Gc) over complex elastic modulus(E∗). This deconvolution of bulk and interfacial contributions to the friction of soft materials leads to interesting predictions that will impact material design for a wide range of applications.

Direct Methods Of Determining Traffic Stream Characteristics By Definition, John D. Leonard, Daiheng Ni

Daiheng Ni

There are generally two approaches to derive traffic stream characteristic s (i.e. flow, space mean speed, and density): indirect approach which derives traffic stream characteristics by estimation from correlated variable(s) and direct approach which determines traffic stream characteristics by definition from field observations. A method of the former approach inevitably involves estimation error while a method of the latter provides “the ground truth”. This paper examines and contrasts three direct methods, namely the HCM method, the x-t method, and the n-t method. The HCM method determines traffic stream characteristics based on their definition adopted by Highway Capacity Manual (HCM). The …

How To Select A Good Alternate Path In Large Peer-To-Peer Systems?, T Fei, S Tao, Lx Gao, R Guerin

Lixin Gao

No abstract provided.

Field-Programmable Gate Arrays In Embedded Systems, Miriam Leeser, Scott Hauck, Russell Tessier

Russell Tessier

No abstract provided.

Considerations For Bistatic Probing Of Clear-Air Winds In The Atmospheric Boundary Layer, Stephen Frasier, Z. C. Tulu, R. Janaswamy, D. J. Mclaughlin

Stephen Frasier

Bistatic radar measurement of clear-air winds in the atmospheric boundary layer is considered. The context is three-dimensional wind field measurement using dense networks of short-range radars configured to operate in bistatic geometries. Such networks exploit a combination of Rayleigh scattering from insects and Bragg scattering from refractive index turbulence, the latter exhibiting enhanced scattering intensity in forward scatter geometries compared to the monostatic case. Bistatic radar fundamentals are reviewed, and beam-limited scattering volumes are considered. Measurements with sufficient precision (<1 m s−1) are achievable with relatively low average powers (100 W) with reasonably short dwell times (1 s) for transmitters and receivers separated by as much as 15 km. For a fixed antenna aperture size, frequency dependence of sensitivity for the Bragg component of the composite scattered signal is weak (λ2/3), provided that the Bragg-resonant wave number for the forward scattering geometry lies within the inertial subrange of refractive index turbulence. In contrast, the strong (λ4) frequency-dependent Rayleigh insect echo dominates the scattered signal for short wavelengths (i.e., X band and higher frequencies) under many conditions except for small forward scatter angles. Owing to this dominance and to the tendency for refractive index turbulence and insects to occur together in the atmospheric boundary layer, reliance on the bistatic Bragg scattering mechanism is not warranted for short-range, short-wavelength radar networks.

Influence Of Defects On Nanotube Transistor Performance, Eric Polizzi, Neophytos Neophytou, Diego Kienle, M. P. Anantram

Eric Polizzi

We study the effect of vacancies and charged impurities on the performance of carbon nanotube transistors by self-consistently solving the three-dimensional Poisson and Schrödinger equations. We find that a single vacancy or charged impurity can decrease the drive current by more than 25% from the ballistic current. The threshold voltage shift in the case of charged impurities can be as large as 40 mV.

Robust Egress Interdomain Traffic Engineering, J Qiu, Lx Gao

Lixin Gao

No abstract provided.

Dual-Polarized C- And Ku-Band Ocean Backscatter Response To Hurricane-Force Winds, Stephen Frasier, D. Esteban-Fernandez, J. R. Carswell, P. S. Chang, P. G. Black, F. D. Marks

Stephen Frasier

Airborne ocean backscatter measurements at C- and Ku-band wavelengths and H and V polarizations at multiple incidence angles obtained in moderate to very high wind speed conditions (25–65 m s−1) during missions through several tropical cyclones are presented. These measurements clearly show that the normalized radar cross sections (NRCS) response stops increasing at hurricane-force winds for both frequency bands and polarizations except for high incidence angles at C-band and H polarization. The results also show the mean NRCS departing from a power law behavior for all the presented frequency bands, polarizations, and incidence angles, suggesting a reduction in the drag …