Engineering | Open Access Articles | Digital Commons Network™

Energy, U.S. Department Of, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides information about the U.S. Department of Energy (DOE) and its predecessor agencies and how DOE influences federal energy policy and scientific research in the western U.S.

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Army Corps Of Engineers, U.S., Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides an overview of how the U.S. Army Corps of Engineers has influenced historical and contemporary economic, environmental, and political developments in the American West.

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Aridity, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides an overview of how aridity in the American West has influenced that region's economic, environmental, and political development and U.S. Government policies in this region.

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Colorado River Compact (1922), Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides an overview of the 1922 Colorado River Compact seeking to fairly distribute Colorado River water to Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming and their increasing populations.

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Hydroelectric Power, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides a historical overview and contemporary analysis of the advantages and disadvantages of federal government support for hydroelectric power in the American West.

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Oil Industry, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides an overview of the historical and contemporary development of the American oil industry and how it has impacted U.S. natural resources policies in the American west.

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Mining, Uranium, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Provides an overview of uranium mining's role and influence in the American West with comparative information on uranium mining in foreign countries.

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Quantum Criticality Analysis By Finite-Size Scaling And Exponential Basis Sets, Fahhad H. Alberbi, Sabre Kais

Birck and NCN Publications

We combine the finite-size scaling method with the mesh-free spectral method to calculate quantum critical parameters for a given Hamiltonian. The basic idea is to expand the exact wave function in a finite exponential basis set and extrapolate the information about system criticality from a finite basis to the infinite basis set limit. The used exponential basis set, though chosen intuitively, allows handling a very wide range of exponential decay rates and calculating multiple eigenvalues simultaneously. As a benchmark system to illustrate the combined approach, we choose the Hulthen potential. The results show that the method is very accurate and …

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Broadband Enhancement Of Spontaneous Emission From Nitrogen-Vacancy Centers In Nanodiamonds By Hyperbolic Metamaterials, Mikhail Y. Shalaginov, Satoshi Ishii, J. Liu, Joseph Irudayaraj, A. Lagutchev, Alexander V. Kildishev, Vladimir M. Shalaev

Birck and NCN Publications

We experimentally demonstrate a broadband enhancement of emission from nitrogen-vacancy centers in nanodiamonds. The enhancement is achieved by using a multilayer metamaterial with hyperbolic dispersion. The metamaterial is fabricated as a stack of alternating gold and alumina layers. Our approach paves the way towards the construction of efficient single-photon sources as planar on-chip devices. (C) 2013 AIP Publishing LLC.

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Pre-Breakdown Evaluation Of Gas Discharge Mechanisms In Microgaps, Abbas Semnani, Ayyaswamy Venkattraman, Alina A. Alexeenko, Dimitrios Peroulis

Birck and NCN Publications

The individual contributions of various gas discharge mechanisms to total pre-breakdown current in microgaps are quantified numerically. The variation of contributions of field emission and secondary electron emission with increasing electric field shows contrasting behavior even for a given gap size. The total current near breakdown decreases rapidly with gap size indicating that microscale discharges operate in a high-current, low-voltage regime. This study provides the first such analysis of breakdown mechanisms and aids in the formulation of physics-based theories for microscale breakdown. (C) 2013 AIP Publishing LLC

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Evidence For Effective Mass Reduction In Gaas/Algaas Quantum Wells, A. T. Hatke, M. A. Zudov, J. D. Watson, Michael J. Manfra, L. N. Pfeiffer, K. W. West

Birck and NCN Publications

We have performed microwave photoresistance measurements in high mobility GaAs/AlGaAs quantum wells and investigated the value of the effective mass. Surprisingly, the effective mass, obtained from the period of microwave-induced resistance oscillations, is found to be about 12% lower than the band mass in GaAs, m(b)*. This finding provides strong evidence for electron-electron interactions which can be probed by microwave photoresistance in very high Landau levels. In contrast, the measured magnetoplasmon dispersion revealed an effective mass which is close to m(b)*, in accord with previous studies. DOI: 10.1103/PhysRevB.87.161307

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Sustainability In Industrial Logistics Operations, Vishnu Siddharth Somanur Paramasivam

Purdue Polytechnic Directed Projects

CO2 concentration in the atmosphere has been rising at a rapid rate. As per the numbers quoted, the concentration has surpassed the safest upper limit suggested by the scientists. CO2 is a green-house gas and is partially responsible for global warming. With the current rate of emissions, it poses a threat to the planet's future and prosperity. Transportation contributes 30% of the overall CO2 emissions. Companies that use transportation are taking sustainability initiatives to reduce the emissions. This project documented some of the sustainability practices followed by the companies currently. It was found that the practices followed three general methods …

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Thermoelectric Properties Of Epitaxial Scn Films Deposited By Reactive Magnetron Sputtering Onto Mgo(001) Substrates, Polina V. Burmistrova, Jesse Maassen, Tela Favaloro, Bivas Saha, Shuaib Salamat, Yee Rui Koh, Mark S. Lundstrom, Ali Shakouri, Timothy D. Sands

Birck and NCN Publications

Epitaxial ScN(001) thin films were grown on MgO(001) substrates by dc reactive magnetron sputtering. The deposition was performed in an Ar/N-2 atmosphere at 2 x 10(-3) Torr at a substrate temperature of 850 degrees C in a high vacuum chamber with a base pressure of 10(-8) Torr. In spite of oxygen contamination of 1.6 +/- 1 at. %, the electrical resistivity, electron mobility, and carrier concentration obtained from a typical film grown under these conditions by room temperature Hall measurements are 0.22 m Omega cm, 106 cm(2) V-1 s(-1), and 2.5 x 10(20) cm(-3), respectively. These films exhibit remarkable thermoelectric …

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Length And Temperature Dependent 1/F Noise In Vertical Single-Walled Carbon Nanotube Arrays, Robert A. Sayer, Jeffrey D. Engerer, N. S. Vidhyadhiraja, Timothy S. Fisher

Birck and NCN Publications

We report measurements of temperature-and length-dependent 1/f noise in vertical single-walled carbon nanotube (SWCNT) arrays. Carbon nanotubes are synthesized in a porous anodic alumina template with sub-micrometer channel lengths ranging from 100 to 700 nm. A significant difference is observed in the 1/f noise magnitude of quasi-ballistic and diffusive SWCNT devices, with quasi-ballistic devices exhibiting 1/f noise levels that are one to two orders of magnitude less than diffusively conducting devices. Furthermore, 1/f noise was measured from 90 to 400 K, and the noise prefactor decreased significantly at temperatures below 250 K. (C) 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4800856]

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Universal Scaling And Intrinsic Classification Of Electro-Mechanical Actuators, Sambit Palit, Ankit Jain, Muhammad A. Alam

Birck and NCN Publications

Actuation characteristics of electromechanical (EM) actuators have traditionally been studied for a few specific regular electrode geometries and support (anchor) configurations. The ability to predict actuation characteristics of electrodes of arbitrary geometries and complex support configurations relevant for broad range of applications in switching, displays, and varactors, however, remains an open problem. In this article, we provide four universal scaling relationships for EM actuation characteristics that depend only on the mechanical support configuration and the corresponding electrode geometries, but are independent of the specific geometrical dimensions and material properties of these actuators. These scaling relationships offer an intrinsic classification for …

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Atomic Force Microscopy-Coupled Microcoils For Cellular-Scale Nuclear Magnetic Resonance Spectroscopy, Charilaos Mousoulis, Teimour Maleki, Babak Ziaie, Corey Neu

Birck and NCN Publications

We present the coupling of atomic force microscopy (AFM) and nuclear magnetic resonance (NMR) technologies to enable topographical, mechanical, and chemical profiling of biological samples. Here, we fabricate and perform proof-of-concept testing of radiofrequency planar microcoils on commercial AFM cantilevers. The sensitive region of the coil was estimated to cover an approximate volume of 19.4 x 10(3) mu m(3) (19.4 pl). Functionality of the spectroscopic module of the prototype device is illustrated through the detection of H-1 resonance in deionized water. The acquired spectra depict combined NMR capability with AFM that may ultimately enable biophysical and biochemical studies at the …

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Mechanism Of Fatigue Performance Enhancement In A Laser Sintered Superhard Nanoparticles Reinforced Nanocomposite Followed By Laser Shock Peening, Dong Lin, Chang Ye, Yiliang Liao, Sergey Suslov, Richard Liu, Gary J. Cheng

Birck and NCN Publications

This study investigates the fundamental mechanism of fatigue performance enhancement during a novel hybrid manufacturing process, which combines laser sintering of superhard nanoparticles integrated nanocomposites and laser shock peening (LSP). Through laser sintering, TiN nanoparticles are integrated uniformly into iron matrix to form a nanocomposite layer near the surface of AISI4140 steel. LSP is then performed on the nanocomposite layer to generate interaction between nanoparticles and shock waves. The fundamental mechanism of fatigue performance enhancement is discussed in this paper. During laser shock interaction with the nanocomposites, the existence of nanoparticles increases the dislocation density and also helps to pin …

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Cleerhub.Org Adoption By Eafit University Engineering Faculty Members: A Longitudinal Study, Diego M. Mendez Mena

Purdue Polytechnic Masters Theses

The main purpose of this study is to identify and comprehend faculty members’ perception of attributes of the diffusion of the technological innovation CLEERhub.org at EAFIT University, College of Engineering, in Medellin, Colombia. Moreover, this work attempts to understand causes and motivators that might lead to innovation adoption or rejection. The Diffusion of Innovations Theory serves as the framework to develop an appropriate assessing instrument that allows accurate measuring of user opinions towards the practice of CLEERhub.org in their educational research work in Engineering. In order to correctly assess user perception of the embracement process of such technological/cyberinfrastructure innovation, the …

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Control Charts As A Productivity Improvement Tool In Construction, Jospeh Hubert Ault

Purdue Polytechnic Masters Theses

This study examined the use of individuals control charts to facilitate the productivity improvement of repetitive construction processes. Cycles times for excavation, forming, and reinforcing processes were observed using stratified random sampling during the construction of six residential home foundations. The cycle time information was plotted on control charts followed by an intervention, with the applicable crew members and management, to analyze the charts and propose solutions to any problems identified. Following the intervention, more samples were collected for comparison to the baseline observations collected before the intervention. The mean cycle times were compared before and after the interventions using …

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Enhanced Diagnostic Accuracy Of Mammograms On A Mobile Device, Sharanya Padmanabhan

Open Access Theses

With the death of a woman every 13 minutes in the US, and one every minute worldwide, due to breast cancer, the need for early detection cannot be overstated. Mammography is a boon for both early detection and screening of breast tumors. It is an imaging system that uses low dose (9mrem) x-rays for examining the breasts, by the electrons reflected from the tissues (thermoelectric effect). However, there are 20% false positives and 10% false negatives in current practice. Hence, there is a critical need for enhancing the accuracy of these mammograms. Towards this, this thesis was aimed at enhancing …

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Assessment Procedures For Paved And Gravel Roads, Claudio Figueroa, Bradley Fotsch, Sarah M. Hubbard, John Haddock

Indiana Local Technical Assistance Program (LTAP) Publications

The funding available to local agencies in Indiana to manage roadways has decreased in recent years, and many agencies cannot provide adequate maintenance with the available resources. Consequently, agencies are doing everything they can to evaluate the least expensive method to maintain their roads that will meet their objectives and needs. In some cases, the most appropriate surface type is a paved road, and in some cases, it is a gravel road. The decision as to the most appropriate surface type depends on a variety of factors, such as cost, traffic volume, development and public input. The purpose of this …

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Nanopatterning Of Metal-Coated Silicon Surfaces Via Ion Beam Irradiation: Real Time X-Ray Studies Reveal The Effect Of Silicide Bonding, Osman El-Atwani, Sean Gonderman, Alexander Demasi, Anastassiya Suslova, Justin Fowler, Mohamad El-Atwani, Karl Ludwig, Jean Paul Allain

Birck and NCN Publications

We investigated the effect of silicide formation on ion-induced nanopatterning of silicon with various ultrathin metal coatings. Silicon substrates coated with 10 nm Ni, Fe, and Cu were irradiated with 200 eV argon ions at normal incidence. Real time grazing incidence small angle x-ray scattering (GISAXS) and x-ray fluorescence (XRF) were performed during the irradiation process and real time measurements revealed threshold conditions for nanopatterning of silicon at normal incidence irradiation. Three main stages of the nanopatterning process were identified. The real time GISAXS intensity of the correlated peaks in conjunction with XRF revealed that the nanostructures remain for a …

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Full Band Calculations Of The Intrinsic Lower Limit Of Contact Resistivity, Jesse Maassen, C. Jeong, A. Baraskar, M. Rodwell, Mark S. Lundstrom

Birck and NCN Publications

The intrinsic lower limit of contact resistivity (rho(LL)(c)) for InAs, In0.53Ga0.47As, GaSb, and Si is calculated using a full band ballistic quantum transport approach. Surprisingly, our results show that rho(LL)(c) is almost independent of the semiconductor. An analytical model, derived for 1D, 2D, and 3D, correctly reproduces the numerical results and explains why rho(LL)(c) is very similar in all cases. Our analysis sets a minimal carrier density required to meet the International Technology Roadmap for Semiconductors call for rho(c) x 10(-9) Omega-cm(2) by 2023. Comparison with experiments shows there is room for improvement, which will come from optimizing interfacial properties. …

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Coupled Vibrational Modes In Multiple-Filled Skutterudites And The Effects On Lattice Thermal Conductivity Reduction, Liang Guo, Xianfan Xu, J. R. Salvador, G. P. Meisner

Birck and NCN Publications

The influence of guest atoms on thermal conduction in filled skutterudites was studied using ultrafast reflectance spectroscopy. Different filling species cause coupled vibrational modes between the guest atoms and the host lattice at different frequencies, which scatter phonons in different spectral spans. Using a Debye model for the measured lattice thermal conductivity together with the measured vibration frequencies and scattering rates, it is shown that scattering due to the coupled vibrational modes has a considerable contribution to the suppression of lattice thermal conduction. This demonstrates that filling with multiple species can efficiently reduce the lattice thermal conductivity in skutterudites. (C) …

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Thermoreflectance Imaging Of Sub 100 Ns Pulsed Cooling In High-Speed Thermoelectric Microcoolers, Bjorn Vermeersch, Je-Hyeong Bahk, James Christofferson, Ali Shakouri

Birck and NCN Publications

Miniaturized thin film thermoelectric coolers have received considerable attention as potential means to locally address hot spots in microprocessors. Given the highly dynamic workload in complex integrated circuits, the need arises for a thorough understanding of the high-speed thermal behavior of microcoolers. Although some prior work on transient Peltier cooling in pulsed operation is available, these studies mostly focus on theoretical modeling and typically deal with relatively large modules with time constants well into the millisecond range. In this paper, we present an extensive experimental characterization of 30 x 30 mu m(2) high-speed coplanar SiGe superlattice microcoolers subjected to 300 …

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Shape Memory Metamaterials With Tunable Thermo-Mechanical Response Via Hetero-Epitaxial Integration: A Molecular Dynamics Study, Karthik Guda Vishnu, Alejandro Strachan

Birck and NCN Publications

We show that nanoscale epitaxial superlattices (SLs) can be used to engineer the energy landscape that governs the martensitic transformation in shape memory alloys and tune their thermo-mechanical response. We demonstrate the approach using large-scale molecular dynamics simulations of a SL material consisting of alternate layers of a shape memory Ni-rich NiAl alloy and NiAl B2 alloy. The non-martensitic NiAl alloy was chosen to reduce the energy barrier that separates the martensite and austenite phases of the SL and its incorporation leads to a reduction in the thermal hysteresis of the transition. This is a desirable feature in applications involving …

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Characterizing Reliability Of Manual Intersection Turning Movement Counts Using Modern Data Collection Technology, Gary Shoup, Steve M. Remias, Alexander M. Hainen, Gannon Grimmer, Alexander D. Davis

JTRP Other Publications and Reports

Collecting intersection turning movement counts at intersections is an essential data collection task for many types of traffic engineering studies. On a daily basis, consulting firms and agencies collect turning movement counts that are used for preparing traffic impact studies, determining design hours for road improvements, and the retiming of traffic signals. Although there is a substantial body of literature on the stochastic nature of traffic volumes and how they vary by time, day of week, and season, the literature is quite sparse on how accurately turning movement counts can be collected at signalized intersections. The objective of this paper …

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Trail Data Acquisition, Amy Hartzog, Greg Lindsey, Rory Robinson

Purdue Road School

Trail usage is one of the most frequently asked questions when planning and maintaining trails. From building justification to maintenance dollars, community leaders want to know how many people are being served by the trail. This session will explain to the attendees the different data collection methods, how the data can be collected and used, and why it is so important.

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The Importance Of Performing Route Surveys In The State Of Indiana, Rodney Kelly, Chester Parsons, Grant Niemeyer

Purdue Road School

This presentation provides an overview of Rule 12 and discuss what is involved in a Location Control Route Survey (LCRS). Details such as where they must be performed, why they are important, their benefits and best practices will be discussed.

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How To Develop And Implement A Successful In-House Chip Seal Program, Bill Tompkins, Gary Vandegriff

Purdue Road School

This session covers the lessons learned from the development of INDOT’s in-house chip seal/ fog seal program. Presenters will discuss the methodology involved in candidate selection, material selection and logistics. Presenters will also discuss the statewide effort to provide training and support to the INDOT staff that has reintroduced this age old surface treatment as a viable, economical, and effective pavement preservation treatment.

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Full-Text Articles in Engineering

Energy, U.S. Department Of, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Army Corps Of Engineers, U.S., Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Aridity, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Colorado River Compact (1922), Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Hydroelectric Power, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Oil Industry, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Mining, Uranium, Bert Chapman

Libraries Faculty and Staff Scholarship and Research

Quantum Criticality Analysis By Finite-Size Scaling And Exponential Basis Sets, Fahhad H. Alberbi, Sabre Kais

Birck and NCN Publications

Broadband Enhancement Of Spontaneous Emission From Nitrogen-Vacancy Centers In Nanodiamonds By Hyperbolic Metamaterials, Mikhail Y. Shalaginov, Satoshi Ishii, J. Liu, Joseph Irudayaraj, A. Lagutchev, Alexander V. Kildishev, Vladimir M. Shalaev

Birck and NCN Publications

Pre-Breakdown Evaluation Of Gas Discharge Mechanisms In Microgaps, Abbas Semnani, Ayyaswamy Venkattraman, Alina A. Alexeenko, Dimitrios Peroulis

Birck and NCN Publications

Evidence For Effective Mass Reduction In Gaas/Algaas Quantum Wells, A. T. Hatke, M. A. Zudov, J. D. Watson, Michael J. Manfra, L. N. Pfeiffer, K. W. West

Birck and NCN Publications

Sustainability In Industrial Logistics Operations, Vishnu Siddharth Somanur Paramasivam

Purdue Polytechnic Directed Projects

Thermoelectric Properties Of Epitaxial Scn Films Deposited By Reactive Magnetron Sputtering Onto Mgo(001) Substrates, Polina V. Burmistrova, Jesse Maassen, Tela Favaloro, Bivas Saha, Shuaib Salamat, Yee Rui Koh, Mark S. Lundstrom, Ali Shakouri, Timothy D. Sands

Birck and NCN Publications

Length And Temperature Dependent 1/F Noise In Vertical Single-Walled Carbon Nanotube Arrays, Robert A. Sayer, Jeffrey D. Engerer, N. S. Vidhyadhiraja, Timothy S. Fisher

Birck and NCN Publications

Universal Scaling And Intrinsic Classification Of Electro-Mechanical Actuators, Sambit Palit, Ankit Jain, Muhammad A. Alam

Birck and NCN Publications

Atomic Force Microscopy-Coupled Microcoils For Cellular-Scale Nuclear Magnetic Resonance Spectroscopy, Charilaos Mousoulis, Teimour Maleki, Babak Ziaie, Corey Neu

Birck and NCN Publications

Mechanism Of Fatigue Performance Enhancement In A Laser Sintered Superhard Nanoparticles Reinforced Nanocomposite Followed By Laser Shock Peening, Dong Lin, Chang Ye, Yiliang Liao, Sergey Suslov, Richard Liu, Gary J. Cheng

Birck and NCN Publications

Cleerhub.Org Adoption By Eafit University Engineering Faculty Members: A Longitudinal Study, Diego M. Mendez Mena

Purdue Polytechnic Masters Theses

Control Charts As A Productivity Improvement Tool In Construction, Jospeh Hubert Ault

Purdue Polytechnic Masters Theses

Enhanced Diagnostic Accuracy Of Mammograms On A Mobile Device, Sharanya Padmanabhan

Open Access Theses

Assessment Procedures For Paved And Gravel Roads, Claudio Figueroa, Bradley Fotsch, Sarah M. Hubbard, John Haddock

Indiana Local Technical Assistance Program (LTAP) Publications

Nanopatterning Of Metal-Coated Silicon Surfaces Via Ion Beam Irradiation: Real Time X-Ray Studies Reveal The Effect Of Silicide Bonding, Osman El-Atwani, Sean Gonderman, Alexander Demasi, Anastassiya Suslova, Justin Fowler, Mohamad El-Atwani, Karl Ludwig, Jean Paul Allain

Birck and NCN Publications

Full Band Calculations Of The Intrinsic Lower Limit Of Contact Resistivity, Jesse Maassen, C. Jeong, A. Baraskar, M. Rodwell, Mark S. Lundstrom

Birck and NCN Publications

Coupled Vibrational Modes In Multiple-Filled Skutterudites And The Effects On Lattice Thermal Conductivity Reduction, Liang Guo, Xianfan Xu, J. R. Salvador, G. P. Meisner

Birck and NCN Publications

Thermoreflectance Imaging Of Sub 100 Ns Pulsed Cooling In High-Speed Thermoelectric Microcoolers, Bjorn Vermeersch, Je-Hyeong Bahk, James Christofferson, Ali Shakouri

Birck and NCN Publications

Shape Memory Metamaterials With Tunable Thermo-Mechanical Response Via Hetero-Epitaxial Integration: A Molecular Dynamics Study, Karthik Guda Vishnu, Alejandro Strachan

Birck and NCN Publications

Characterizing Reliability Of Manual Intersection Turning Movement Counts Using Modern Data Collection Technology, Gary Shoup, Steve M. Remias, Alexander M. Hainen, Gannon Grimmer, Alexander D. Davis

JTRP Other Publications and Reports

Trail Data Acquisition, Amy Hartzog, Greg Lindsey, Rory Robinson

Purdue Road School

The Importance Of Performing Route Surveys In The State Of Indiana, Rodney Kelly, Chester Parsons, Grant Niemeyer

Purdue Road School

How To Develop And Implement A Successful In-House Chip Seal Program, Bill Tompkins, Gary Vandegriff

Purdue Road School