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Showing papers by "Virginia Tech published in 2013"


Journal ArticleDOI
Fiona A. Harrison1, William W. Craig2, William W. Craig3, Finn Erland Christensen4, Charles J. Hailey5, William W. Zhang6, Steven E. Boggs3, Daniel Stern1, W. Rick Cook1, Karl Forster1, Paolo Giommi, Brian W. Grefenstette1, Yunjin Kim1, Takao Kitaguchi7, Jason E. Koglin5, Kristin K. Madsen1, Peter H. Mao1, Hiromasa Miyasaka1, Kaya Mori5, M. Perri8, Michael J. Pivovaroff2, Simonetta Puccetti8, Vikram Rana1, Niels Jørgen Stenfeldt Westergaard4, J. L. Willis1, Andreas Zoglauer3, Hongjun An9, Matteo Bachetti10, Matteo Bachetti11, Nicolas M. Barrière3, Eric C. Bellm1, Varun Bhalerao1, Varun Bhalerao12, Nicolai Brejnholt4, Felix Fuerst1, Carl Christian Liebe1, Craig B. Markwardt6, Melania Nynka5, Julia Vogel2, Dominic J. Walton1, Daniel R. Wik6, David M. Alexander13, L. R. Cominsky14, Ann Hornschemeier6, Allan Hornstrup4, Victoria M. Kaspi9, Greg Madejski, Giorgio Matt15, S. Molendi7, David M. Smith16, John A. Tomsick3, Marco Ajello3, David R. Ballantyne17, Mislav Baloković1, Didier Barret11, Didier Barret10, Franz E. Bauer18, Roger Blandford8, W. Niel Brandt19, Laura Brenneman20, James Chiang8, Deepto Chakrabarty21, Jérôme Chenevez4, Andrea Comastri7, Francois Dufour9, Martin Elvis20, Andrew C. Fabian22, Duncan Farrah23, Chris L. Fryer24, Eric V. Gotthelf5, Jonathan E. Grindlay20, D. J. Helfand25, Roman Krivonos3, David L. Meier1, Jon M. Miller26, Lorenzo Natalucci7, Patrick Ogle1, Eran O. Ofek27, Andrew Ptak6, Stephen P. Reynolds28, Jane R. Rigby6, Gianpiero Tagliaferri7, Stephen E. Thorsett29, Ezequiel Treister30, C. Megan Urry31 
TL;DR: The Nuclear Spectroscopic Telescope Array (NuSTAR) as discussed by the authors is the first focusing high-energy X-ray telescope in orbit, which operates in the band from 3 to 79 keV.
Abstract: The Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched on 2012 June 13, is the first focusing high-energy X-ray telescope in orbit. NuSTAR operates in the band from 3 to 79 keV, extending the sensitivity of focusing far beyond the ~10 keV high-energy cutoff achieved by all previous X-ray satellites. The inherently low background associated with concentrating the X-ray light enables NuSTAR to probe the hard X-ray sky with a more than 100-fold improvement in sensitivity over the collimated or coded mask instruments that have operated in this bandpass. Using its unprecedented combination of sensitivity and spatial and spectral resolution, NuSTAR will pursue five primary scientific objectives: (1) probe obscured active galactic nucleus (AGN) activity out to the peak epoch of galaxy assembly in the universe (at z ≾ 2) by surveying selected regions of the sky; (2) study the population of hard X-ray-emitting compact objects in the Galaxy by mapping the central regions of the Milky Way; (3) study the non-thermal radiation in young supernova remnants, both the hard X-ray continuum and the emission from the radioactive element ^(44)Ti; (4) observe blazars contemporaneously with ground-based radio, optical, and TeV telescopes, as well as with Fermi and Swift, to constrain the structure of AGN jets; and (5) observe line and continuum emission from core-collapse supernovae in the Local Group, and from nearby Type Ia events, to constrain explosion models. During its baseline two-year mission, NuSTAR will also undertake a broad program of targeted observations. The observatory consists of two co-aligned grazing-incidence X-ray telescopes pointed at celestial targets by a three-axis stabilized spacecraft. Deployed into a 600 km, near-circular, 6° inclination orbit, the observatory has now completed commissioning, and is performing consistent with pre-launch expectations. NuSTAR is now executing its primary science mission, and with an expected orbit lifetime of 10 yr, we anticipate proposing a guest investigator program, to begin in late 2014.

1,966 citations


Journal ArticleDOI
TL;DR: A comprehensive voxel-based examination of the impact of motion on the BOLD signal suggests that positive relationships may reflect neural origins of motion while negative relationships are likely to originate from motion artifact.

1,300 citations


Journal ArticleDOI
16 Aug 2013-Polymer
TL;DR: A review of the fundamental scientific principles underpinning the operation of polymers for gas separations, including the solution-diffusion model and various structure/property relations, is presented in this paper.

1,095 citations


Journal ArticleDOI
TL;DR: A novel patient-centric framework and a suite of mechanisms for data access control to PHRs stored in semitrusted servers are proposed and a high degree of patient privacy is guaranteed simultaneously by exploiting multiauthority ABE.
Abstract: Personal health record (PHR) is an emerging patient-centric model of health information exchange, which is often outsourced to be stored at a third party, such as cloud providers. However, there have been wide privacy concerns as personal health information could be exposed to those third party servers and to unauthorized parties. To assure the patients' control over access to their own PHRs, it is a promising method to encrypt the PHRs before outsourcing. Yet, issues such as risks of privacy exposure, scalability in key management, flexible access, and efficient user revocation, have remained the most important challenges toward achieving fine-grained, cryptographically enforced data access control. In this paper, we propose a novel patient-centric framework and a suite of mechanisms for data access control to PHRs stored in semitrusted servers. To achieve fine-grained and scalable data access control for PHRs, we leverage attribute-based encryption (ABE) techniques to encrypt each patient's PHR file. Different from previous works in secure data outsourcing, we focus on the multiple data owner scenario, and divide the users in the PHR system into multiple security domains that greatly reduces the key management complexity for owners and users. A high degree of patient privacy is guaranteed simultaneously by exploiting multiauthority ABE. Our scheme also enables dynamic modification of access policies or file attributes, supports efficient on-demand user/attribute revocation and break-glass access under emergency scenarios. Extensive analytical and experimental results are presented which show the security, scalability, and efficiency of our proposed scheme.

1,057 citations


Journal ArticleDOI
TL;DR: In this article, the authors present a systematical technology review essential for the development and application of SST in the distribution system, including high-voltage power devices, high-power and high-frequency transformers, ac/ac converter topologies, and future research directions.
Abstract: The solid-state transformer (SST), which has been regarded as one of the 10 most emerging technologies by Massachusetts Institute of Technology (MIT) Technology Review in 2010, has gained increasing importance in the future power distribution system. This paper presents a systematical technology review essential for the development and application of SST in the distribution system. The state-of-the-art technologies of four critical areas are reviewed, including high-voltage power devices, high-power and high-frequency transformers, ac/ac converter topologies, and applications of SST in the distribution system. In addition, future research directions are presented. It is concluded that the SST is an emerging technology for the future distribution system.

897 citations


Journal ArticleDOI
TL;DR: In this paper, the authors proposed integration of MFCs with other treatment technologies to form an MFC-centered treatment scheme based on thoroughly analyzing the challenges and opportunities, and discuss future efforts to be made for realizing sustainable wastewater treatment.
Abstract: Microbial fuel cells (MFCs) have been conceived and intensively studied as a promising technology to achieve sustainable wastewater treatment. However, doubts and debates arose in recent years regarding the technical and economic viability of this technology on a larger scale and in a real-world applications. Hence, it is time to think about and examine how to recalibrate this technology's role in a future paradigm of sustainable wastewater treatment. In the past years, many good ideas/approaches have been proposed and investigated for MFC application, but information is scattered. Various review papers were published on MFC configuration, substrates, electrode materials, separators and microbiology but there is lack of critical thinking and systematic analysis of MFC application niche in wastewater treatment. To systematically formulate a strategy of (potentially) practical MFC application and provide information to guide MFC development, this perspective has critically examined and discussed the problems and challenges for developing MFC technology, and identified a possible application niche whereby MFCs can be rationally incorporated into the treatment process. We propose integration of MFCs with other treatment technologies to form an MFC-centered treatment scheme based on thoroughly analyzing the challenges and opportunities, and discuss future efforts to be made for realizing sustainable wastewater treatment.

748 citations


Journal ArticleDOI
TL;DR: Environmental releases of antibiotics and antibiotic-resistant bacteria can in many cases be reduced at little or no cost and the anticipated benefit is an extended useful life span for current and future antibiotics.
Abstract: Background: There is growing concern worldwide about the role of polluted soil and water environments in the development and dissemination of antibiotic resistance.Objective: Our aim in this study ...

659 citations


Journal ArticleDOI
TL;DR: It is revealed that MI consistently recruits a large fronto-parietal network in addition to subcortical and cerebellar regions, the first quantitative cortical map of MI, and methodological issues that should be addressed in future research are highlighted.

639 citations


Journal ArticleDOI
18 Apr 2013-Nature
TL;DR: Despite the overall downturn in cosmic star formation towards the highest redshifts, it seems that environments mature enough to form the most massive, intense starbursts existed at least as early as 880 million years after the Big Bang.
Abstract: Massive present-day early-type (elliptical and lenticular) galaxies probably gained the bulk of their stellar mass and heavy elements through intense, dust-enshrouded starbursts--that is, increased rates of star formation--in the most massive dark-matter haloes at early epochs. However, it remains unknown how soon after the Big Bang massive starburst progenitors exist. The measured redshift (z) distribution of dusty, massive starbursts has long been suspected to be biased low in z owing to selection effects, as confirmed by recent findings of systems with redshifts as high as ~5 (refs 2-4). Here we report the identification of a massive starburst galaxy at z = 6.34 through a submillimetre colour-selection technique. We unambiguously determined the redshift from a suite of molecular and atomic fine-structure cooling lines. These measurements reveal a hundred billion solar masses of highly excited, chemically evolved interstellar medium in this galaxy, which constitutes at least 40 per cent of the baryonic mass. A `maximum starburst' converts the gas into stars at a rate more than 2,000 times that of the Milky Way, a rate among the highest observed at any epoch. Despite the overall downturn in cosmic star formation towards the highest redshifts, it seems that environments mature enough to form the most massive, intense starbursts existed at least as early as 880 million years after the Big Bang.

631 citations


Journal ArticleDOI
TL;DR: In this paper, the authors test a theoretical model that links community residents' perceptions of tourism impact (economic, social, cultural, and environmental) with residents' satisfaction with particular life domains (material well-being, community wellbeing, emotional well being, and health and safety wellbeing) and overall life satisfaction.

628 citations


Journal ArticleDOI
Z. Q. Liu, C. P. Shen1, C. Z. Yuan, I. Adachi  +188 moreInstitutions (56)
TL;DR: In a study of Y(4260) → π+ π- J/φ decays, a structure is observed in the M(π(±)J/ψ) mass spectrum with 5.2σ significance that can be interpreted as a new charged charmoniumlike state.
Abstract: The cross section for ee+ e- → π+ π- J/ψ between 3.8 and 5.5 GeV is measured with a 967 fb(-1) data sample collected by the Belle detector at or near the Υ(nS) (n = 1,2,…,5) resonances. The Y(4260) state is observed, and its resonance parameters are determined. In addition, an excess of π+ π- J/ψ production around 4 GeV is observed. This feature can be described by a Breit-Wigner parametrization with properties that are consistent with the Y(4008) state that was previously reported by Belle. In a study of Y(4260) → π+ π- J/ψ decays, a structure is observed in the M(π(±)J/ψ) mass spectrum with 5.2σ significance, with mass M = (3894.5 ± 6.6 ± 4.5) MeV/c2 and width Γ = (63 ± 24 ± 26) MeV/c2, where the errors are statistical and systematic, respectively. This structure can be interpreted as a new charged charmoniumlike state.

Journal ArticleDOI
TL;DR: New insights on the contribution of material properties towards osteoinductivity and the role of signaling molecules involved in osteoblastic differentiation can potentially aid the design of CPC-based biomaterials that support bone regeneration without the need for additional biochemical supplements.

Journal ArticleDOI
05 Dec 2013-Nature
TL;DR: In this article, the future impacts of climate change on landfalling tropical cyclones are unclear, but regardless of this uncertainty, flooding by hurricanes will increase as a result of accelerated sea-level rise.
Abstract: The future impacts of climate change on landfalling tropical cyclones are unclear. Regardless of this uncertainty, flooding by tropical cyclones will increase as a result of accelerated sea-level rise. Under similar rates of rapid sea-level rise during the early Holocene epoch most low-lying sedimentary coastlines were generally much less resilient to storm impacts. Society must learn to live with a rapidly evolving shoreline that is increasingly prone to flooding from tropical cyclones. These impacts can be mitigated partly with adaptive strategies, which include careful stewardship of sediments and reductions in human-induced land subsidence.

Journal ArticleDOI
TL;DR: A flexible model-based approach is proposed to empirically derive and summarize the class-dependent density functions of distal outcomes with categorical, continuous, or count distributions and is demonstrated empirically: latent classes of adolescent depression are used to predict smoking, grades, and delinquency.
Abstract: Although prediction of class membership from observed variables in latent class analysis is well understood, predicting an observed distal outcome from latent class membership is more complicated. A flexible model-based approach is proposed to empirically derive and summarize the class-dependent density functions of distal outcomes with categorical, continuous, or count distributions. A Monte Carlo simulation study is conducted to compare the performance of the new technique to two commonly used classify-analyze techniques: maximum-probability assignment and multiple pseudo-class draws. Simulation results show that the model-based approach produces substantially less biased estimates of the effect compared to either classify-analyze technique, particularly when the association between the latent class variable and the distal outcome is strong. In addition, we show that only the model-based approach is consistent. The approach is demonstrated empirically: latent classes of adolescent depression are used to predict smoking, grades, and delinquency. SAS syntax for implementing this approach using PROC LCA and a corresponding macro are provided.

Journal ArticleDOI
TL;DR: Poor ER may be inherent in ASD and may provide a more parsimonious conceptualization for the many associated socioemotional and behavioral problems in this population.
Abstract: Objective Autism spectrum disorder (ASD) is associated with amplified emotional responses and poor emotional control, but little is known about the underlying mechanisms. This article provides a conceptual and methodologic framework for understanding compromised emotion regulation (ER) in ASD. Method After defining ER and related constructs, methods to study ER were reviewed with special consideration on how to apply these approaches to ASD. Against the backdrop of cognitive characteristics in ASD and existing ER theories, available research was examined to identify likely contributors to emotional dysregulation in ASD. Results Little is currently known about ER in youth with ASD. Some mechanisms that contribute to poor ER in ASD may be shared with other clinical populations (e.g., physiologic arousal, degree of negative and positive affect, alterations in the amygdala and prefrontal cortex), whereas other mechanisms may be more unique to ASD (e.g., differences in information processing/perception, cognitive factors [e.g., rigidity], less goal-directed behavior and more disorganized emotion in ASD). Conclusions Although assignment of concomitant psychiatric diagnoses is warranted in some cases, poor ER may be inherent in ASD and may provide a more parsimonious conceptualization for the many associated socioemotional and behavioral problems in this population. Further study of ER in youth with ASD may identify meaningful subgroups of patients and lead to more effective individualized treatments.

Journal ArticleDOI
Xiaosi Gu1, Xiaosi Gu2, Patrick R. Hof, Karl J. Friston2, Jin Fan 
TL;DR: A model in which AIC serves two major functions: integrating bottom‐up interoceptive signals with top‐down predictions to generate a current awareness state and providing descending predictions to visceral systems that provide a point of reference for autonomic reflexes is proposed.
Abstract: This paper reviews the foundation for a role of the human anterior insular cortex (AIC) in emotional awareness, defined as the conscious experience of emotions. We first introduce the neuroanatomical features of AIC and existing findings on emotional awareness. Using empathy, the awareness and understanding of other people’s emotional states, as a test case, we then present evidence to demonstrate: 1) AIC and anterior cingulate cortex (ACC) are commonly coactivated as revealed by a meta-analysis, 2) AIC is functionally dissociable from ACC, 3) AIC integrates stimulus-driven and top-down information, and 4) AIC is necessary for emotional awareness. We propose a model in which AIC serves two major functions: integrating bottom-up interoceptive signals with top-down predictions to generate a current awareness state and providing descending predictions to visceral systems that provide a point of reference for autonomic reflexes. We argue that AIC is critical and necessary for emotional awareness. J. Comp. Neurol. 521:3371-3388, 2013.

Journal ArticleDOI
TL;DR: In this article, the MiniBooNE experiment at Fermilab reports results from an analysis of ν¯e appearance data from 11.27×10µµ protons on target in the antineutrino mode, an increase of approximately a factor of 2 over the previously reported results.
Abstract: The MiniBooNE experiment at Fermilab reports results from an analysis of ν¯e appearance data from 11.27×10²⁰ protons on target in the antineutrino mode, an increase of approximately a factor of 2 over the previously reported results. An event excess of 78.4±28.5 events (2.8σ) is observed in the energy range 200QEν<1250 MeV. If interpreted in a two-neutrino oscillation model, ν¯μ→ν¯e, the best oscillation fit to the excess has a probability of 66% while the background-only fit has a χ² probability of 0.5% relative to the best fit. The data are consistent with antineutrino oscillations in the 0.01<Δm²<1.0 eV² range and have some overlap with the evidence for antineutrino oscillations from the Liquid Scintillator Neutrino Detector. All of the major backgrounds are constrained by in situ event measurements so nonoscillation explanations would need to invoke new anomalous background processes. The neutrino mode running also shows an excess at low energy of 162.0±47.8 events (3.4σ) but the energy distribution of the excess is marginally compatible with a simple two neutrino oscillation formalism. Expanded models with several sterile neutrinos can reduce the incompatibility by allowing for CP violating effects between neutrino and antineutrino oscillations.

Journal ArticleDOI
TL;DR: In this paper, the authors provide a synthesis of common terminology and explain a rationale and framework for distinguishing among the components of ecosystem service delivery, including: an ecosystem's capacity to produce services; ecological pressures that interfere with the ecosystem's ability to provide the services; societal demand for the service; and flow of the service to people.

Journal ArticleDOI
TL;DR: A review of the history of wireless power transfer and its recent developments is given to show how such technologies can be applied to sensor networks and address their energy constraints.
Abstract: Energy constraints are widely regarded as a fundamental limitation of wireless and mobile devices. For sensor networks, a limited lifetime due to battery constraint poses a performance bottleneck and barrier for large scale deployment. Recently, wireless power transfer has emerged as a promising technology to address energy and lifetime bottlenecks in a sensor network. In this article, we give a review of the history of wireless power transfer and describe its recent developments. We show how such technologies can be applied to sensor networks and address their energy constraints.

Journal ArticleDOI
01 Nov 2013-Mbio
TL;DR: The finding that the emergent U.S. PEDV strains share unique genetic features at the 5′-untranslated region with a bat coronavirus provided further support of the evolutionary origin of P EDV from bats and potential cross-species transmission.
Abstract: Coronaviruses are known to infect humans and other animals and cause respiratory and gastrointestinal diseases. Here we report the emergence of porcine epidemic diarrhea virus (PEDV) in the United States and determination of its origin, evolution, and genotypes based on temporal and geographical evidence. Histological lesions in small intestine sections of affected pigs and the complete genomic sequences of three emergent strains of PEDV isolated from outbreaks in Minnesota and Iowa were characterized. Genetic and phylogenetic analyses of the three U.S. strains revealed a close relationship with Chinese PEDV strains and their likely Chinese origin. The U.S. PEDV strains underwent evolutionary divergence, which can be classified into two sublineages. The three emergent U.S. strains are most closely related to a strain isolated in 2012 from Anhui Province in China, which might be the result of multiple recombination events between different genetic lineages or sublineages of PEDV. Molecular clock analysis of the divergent time based on the complete genomic sequences is consistent with the actual time difference, approximately 2 to 3 years, of the PED outbreaks between China (December 2010) and the United States (May 2013). The finding that the emergent U.S. PEDV strains share unique genetic features at the 5′-untranslated region with a bat coronavirus provided further support of the evolutionary origin of PEDV from bats and potential cross-species transmission. The data from this study have important implications for understanding the ongoing PEDV outbreaks in the United States and will guide future efforts to develop effective preventive and control measures against PEDV. IMPORTANCE The sudden emergence of porcine epidemic diarrhea virus (PEDV), a coronavirus, for the first time in the United States causes significant economic and public health concerns. Since its recognition in May 2013, PEDV has rapidly spread across the United States, resulting in high mortality in piglets in more than 17 States now. The ongoing outbreaks of Middle East respiratory syndrome coronavirus in humans from countries in or near the Arabian Peninsula and the historical deadly nature of the 2002 outbreaks of severe acute respiratory syndrome coronavirus create further anxiety over the emergence of PEDV in the United States due to the lack of scientific information about the origin and evolution of this emerging coronavirus. Here we report the detailed genetic characterization, origin, and evolution of emergent PEDV strains in the United States. The results provide much needed information to devise effective preventive and control strategies against PEDV in the United States.

Journal ArticleDOI
TL;DR: Recent findings on the anti-diabetic effects of dietary flavonoids, including flavan-3-ols, flavanones, flavonols, anthocyanidins, flavones and isoflavones are highlighted, with particular emphasis on the studies that investigated the cellular and molecular mechanisms involved in the beneficial effects of the compounds.
Abstract: Flavonoids are polyphenolic compounds that are abundant in fruits and vegetables, and increasing evidence demonstrates a positive relationship between consumption of flavonoid-rich foods and disease prevention. Epidemiological, in vitro and animal studies support the beneficial effects of dietary flavonoids on glucose and lipid homeostasis. It is encouraging that the beneficial effects of some flavonoids are at physiological concentrations and comparable to clinically-used anti-diabetic drugs; however, clinical research in this field and studies on the anti-diabetic effects of flavonoid metabolites are limited. Flavonoids act on various molecular targets and regulate different signaling pathways in pancreatic β-cells, hepatocytes, adipocytes and skeletal myofibers. Flavonoids may exert beneficial effects in diabetes by (i) enhancing insulin secretion and reducing apoptosis and promoting proliferation of pancreatic β-cells; (ii) improving hyperglycemia through regulation of glucose metabolism in hepatocytes; (iii) reducing insulin resistance, inflammation and oxidative stress in muscle and fat and (iv) increasing glucose uptake in skeletal muscle and white adipose tissue. This review highlights recent findings on the anti-diabetic effects of dietary flavonoids, including flavan-3-ols, flavanones, flavonols, anthocyanidins, flavones and isoflavones, with particular emphasis on the studies that investigated the cellular and molecular mechanisms involved in the beneficial effects of the compounds.

Journal ArticleDOI
TL;DR: In this article, a structural equation modeling approach was used to understand tourists' experience values and extend the theoretical and empirical evidence of causal relationships between the motivation, involvement, and the experience value of the destination.
Abstract: Research acknowledges the tourist as imperative in creating experience value. Building on this premise, the present study offers an integrated approach to understanding tourists’ experience values and attempts to extend the theoretical and empirical evidence of causal relationships between the motivation, involvement, and the experience value of the destination, hereafter called experience value. Using a sample drawn from tourists in Norway, the research model investigates relationships between the three constructs, using a structural equation modeling approach. The results indicate that motivation and involvement are linked to tourists’ experience value and motivation affects the level of involvement. In order to facilitate for tourists to cocreate experience value then, not only should the industry recognize experiences that tourists value but should also acknowledge motivation and involvement as essential in value creation for tourist experiences.


Journal ArticleDOI
TL;DR: A review of available published literature in which nanostructures are incorporated into AM printing media as an attempt to improve the properties of the final printed part is provided in this paper.
Abstract: Purpose – This paper aims to provide a review of available published literature in which nanostructures are incorporated into AM printing media as an attempt to improve the properties of the final printed part. The purpose of this article is to summarize the research done to date, to highlight successes in the field, and to identify opportunities that the union of AM and nanotechnology could bring to science and technology.Design/methodology/approach – Research in which metal, ceramic, and carbon nanomaterials have been incorporated into AM technologies such as stereolithography, laser sintering, fused filament fabrication, and three‐dimensional printing is presented. The results of the addition of nanomaterials into these AM processes are reviewed.Findings – The addition of nanostructured materials into the printing media for additive manufacturing affects significantly the properties of the final parts. Challenges in the application of nanomaterials to additive manufacturing are nevertheless numerous.Re...

Journal ArticleDOI
01 Dec 2013-Cities
TL;DR: In this paper, a conceptual resilience framework is proposed for designing, planning, and managing for resilience by including an evaluation of cultural and process dynamics within cities as well as their physical elements.

Journal ArticleDOI
TL;DR: This paper presents a review of highway-based evacuation modeling and simulation and its evolution over the past decade, including the current state of modeling in the forecasting of evacuation travel demand, distribution and assignment of evacuation demand to regional road networks to reach destinations.
Abstract: This paper presents a review of highway-based evacuation modeling and simulation and its evolution over the past decade. The review includes the major components of roadway transportation planning and operations, including the current state of modeling in the forecasting of evacuation travel demand, distribution and assignment of evacuation demand to regional road networks to reach destinations, assignment of evacuees to various modes of transportation, and evaluation and testing of alternative management strategies to increase capacity of evacuation networks or manage demand. Although this discussion does not cover recent work in other modes used in evacuation such as air, rail, and pedestrian, this paper does highlight recent interdisciplinary modeling work in evacuation to help bridge the gap between the behavioral sciences and engineering and the application of emerging techniques for the verification, validation, and calibration of models. The manuscript also calls attention to special considerations and logistical difficulties, which have received limited attention to date. In addition to these concerns, the following future directions are discussed: further interdisciplinary efforts, including incorporating the medical community; using new technologies for communication of warnings and traffic condition information, data collection, and increased modeling resolution and confidence; using real-time information; and further model refinements and validation.

Book ChapterDOI
TL;DR: A systematic method to evaluate and compare the performance of physical unclonable functions (PUFs) using measured data from PUF implementations in state-of-the-art FPGAs and focuses on the statistical properties of the binary PUF responses.
Abstract: We propose a systematic method to evaluate and compare the performance of physical unclonable functions (PUFs). The need for such a method is justified by the fact that various types of PUFs have been proposed so far. However, there is no common method that can fairly compare them in terms of their performance. We first propose three generic dimensions of PUF measurement. We then define several parameters to quantify the performance of a PUF along these dimensions. We also analyze existing parameters proposed by other researchers. Based on our analysis, we propose a compact set of parameters that will be used as a tool to evaluate as well as compare the performance of different PUFs. To make the method independent of the underlying PUF technique, we focus on the statistical properties of the binary PUF responses. We demonstrate the proposed method with a detailed comparison analysis between two PUFs: the ring-oscillator-based PUF (RO PUF) and the Arbiter-based PUF (APUF) using measured data from PUF implementations in state-of-the-art FPGAs. Finally, we present an online database where our measurements and analysis results can be consulted. Our dataset comprises measurements in 193 FPGAs.

Journal ArticleDOI
TL;DR: This review presents the past and present work on GPU accelerated medical image processing, and is meant to serve as an overview and introduction to existing GPU implementations.

Journal ArticleDOI
TL;DR: A central role for BCAT1 in glioma pathogenesis is suggested, makingBCAT1 and BCAA metabolism attractive targets for the development of targeted therapeutic approaches to treat patients with glioblastoma.
Abstract: Branched-chain amino acid transaminase 1, the enzyme that initiates the catabolism of branched-chain amino acids, is involved in glioma pathogenesis, making it a potential therapeutic target.

Proceedings ArticleDOI
08 May 2013
TL;DR: This paper presents a verifiable privacy-preserving multi-keyword text search (MTS) scheme with similarity-based ranking to address the problem of secure search functions over encrypted data and proposes two secure index schemes to meet the stringent privacy requirements under strong threat models.
Abstract: With the increasing popularity of cloud computing, huge amount of documents are outsourced to the cloud for reduced management cost and ease of access. Although encryption helps protecting user data confidentiality, it leaves the well-functioning yet practically-efficient secure search functions over encrypted data a challenging problem. In this paper, we present a privacy-preserving multi-keyword text search (MTS) scheme with similarity-based ranking to address this problem. To support multi-keyword search and search result ranking, we propose to build the search index based on term frequency and the vector space model with cosine similarity measure to achieve higher search result accuracy. To improve the search efficiency, we propose a tree-based index structure and various adaption methods for multi-dimensional (MD) algorithm so that the practical search efficiency is much better than that of linear search. To further enhance the search privacy, we propose two secure index schemes to meet the stringent privacy requirements under strong threat models, i.e., known ciphertext model and known background model. Finally, we demonstrate the effectiveness and efficiency of the proposed schemes through extensive experimental evaluation.