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Articles 751 - 780 of 3831
Full-Text Articles in Engineering
The Study On The Empty Container Repositioning Of Container Leasing Company, Yi Zhao
The Study On The Empty Container Repositioning Of Container Leasing Company, Yi Zhao
World Maritime University Dissertations
No abstract provided.
Risk Analysis Of Mega Container Ship, Xiaojing Zhu
Risk Analysis Of Mega Container Ship, Xiaojing Zhu
World Maritime University Dissertations
No abstract provided.
Spatio-Temporal Anomaly Detection For Mobile Devices, Guarav Tandon, Philip K. Chan
Spatio-Temporal Anomaly Detection For Mobile Devices, Guarav Tandon, Philip K. Chan
Electrical Engineering and Computer Science Faculty Publications
With the increase in popularity of mobile devices, there has been a significant rise in mobile related security problems. The biggest threat for a mobile subscriber is lost or stolen device, which can lead to confidential data leakage, identity theft, misuse, impersonation, and high service charges. A significant amount of time may elapse between losing a device and disabling it through the service provider, during which an unauthorized malicious user may gain access and incur severe damage. We propose a probabilistic approach to spatio-temporal anomaly detection and evaluate smoothing techniques for sparse data. Our approach outperforms Markov Chain in experiments …
Ccfss Technical Bulletin Fall 2007, Wei-Wen Yu Center For Cold-Formed Steel Structures
Ccfss Technical Bulletin Fall 2007, Wei-Wen Yu Center For Cold-Formed Steel Structures
CCFSS Technical Bulletins (1993 - 2020)
No abstract provided.
Acuta Enews August 2007, Vol. 36, No. 8
Acuta Enews August 2007, Vol. 36, No. 8
ACUTA Newsletters
ln This lssue
From the President ............. Walt Magnussen, Ph,D., Texas A&M University
Tech Talk: ls This a Phone That You Want on Your Network? ............ Kevin Tanzillo, Dux PR 2 ACUTA Resources Make Membership a Great Value
DC Update ............... Jeanne Jansenius, Sewonee, The University of the South
Board Report............... Riny Ledgerwood, San Diego State Univ., ACUTA Sec./Treasurer
IPFIX Standard (NetFlow) and lT Staff |mpact.............. Gary Audin, Delphi lnc.
Check lt Out: RFls/RFPs, Job Postings, Press Releases
FYI: Useful lnformation from the Campus................. Student Monitor
Web Tip: Address Change for ACUTA Listservs ..... Aaron Fuehrer, ACUTA lnformation Technology Mgr. …
Marquette Interchange Phase I Final Report, Nicholas Hornyak, James Crovetti, David Newman, Jay Schabelski
Marquette Interchange Phase I Final Report, Nicholas Hornyak, James Crovetti, David Newman, Jay Schabelski
Transportation Research Center: Marquette Interchange Instrumentation
This report provides details on the design, installation and monitoring of a pavement instrumentation system for the analysis of load-induced stresses and strains within a perpetual HMA pavement system. The HMA pavement was constructed as part of an urban highway improvement project in the City of Milwaukee, Wisconsin. The outer wheel path of the outside lane was instrumented with asphalt strain sensors, base and subgrade pressure sensors, subgrade moisture and temperature sensors, HMA layer temperature sensors, traffic wander strips and a weigh in motion system. Environmental sensors for air temperature, wind speed and solar radiation are also included. The system …
M Solutions Good, M-1 Solutions Better, Luc Longpre, William Gasarch, G. W. Walster, Vladik Kreinovich
M Solutions Good, M-1 Solutions Better, Luc Longpre, William Gasarch, G. W. Walster, Vladik Kreinovich
Departmental Technical Reports (CS)
One of the main objectives of theoretical research in computational complexity and feasibility is to explain experimentally observed difference in complexity.
Empirical evidence shows that the more solutions a system of equations has, the more difficult it is to solve it. Similarly, the more global maxima a continuous function has, the more difficult it is to locate them. Until now, these empirical facts have been only partially formalized: namely, it has been shown that problems with two or more solutions are more difficult to solve than problems with exactly one solution. In this paper, we extend this result and show …
Using Patterns And Composite Propositions To Automate The Generation Of Complex Ltl, Salamah Salamah, Ann Q. Gates, Vladik Kreinovich, Steve Roach
Using Patterns And Composite Propositions To Automate The Generation Of Complex Ltl, Salamah Salamah, Ann Q. Gates, Vladik Kreinovich, Steve Roach
Departmental Technical Reports (CS)
Property classifications and patterns, i.e., high-level abstractions that describe common behavior, have been used to assist practitioners in specifying properties. The Specification Pattern System (SPS) provides descriptions of a collection of patterns. Each pattern is associated with a scope that defines the extent of program execution over which a property pattern is considered. Based on a selected pattern, SPS provides a specification for each type of scope in multiple formal languages including Linear Temporal Logic (LTL). The (Prospec) tool extends SPS by introducing the notion of Composite Propositions (CP), which are classifications for defining sequential and concurrent behavior to represent …
Static Space-Times Naturally Lead To Quasi-Pseudometrics, Hans-Peter A. Kuenzi, Vladik Kreinovich
Static Space-Times Naturally Lead To Quasi-Pseudometrics, Hans-Peter A. Kuenzi, Vladik Kreinovich
Departmental Technical Reports (CS)
The standard 4-dimensional Minkowski space-time of special relativity is based on the 3-dimensional Euclidean metric. In 1967, H.~Busemann showed that similar static space-time models can be based on an arbitrary metric space. In this paper, we search for the broadest possible generalization of a metric under which a construction of a static space-time leads to a physically reasonable space-time model. It turns out that this broadest possible generalization is related to the known notion of a quasi-pseudometric.
Corrosion Effects On Tension Stiffening Behavior Of Reinforced Concrete, M. A. Shayanfar, M. Ghalehnovi, Amir Safiey
Corrosion Effects On Tension Stiffening Behavior Of Reinforced Concrete, M. A. Shayanfar, M. Ghalehnovi, Amir Safiey
Publications
The investigation of corrosion effects on the tensile behavior of reinforced concrete (RC) members is very important in region prone to high corrosion conditions. In this article, an experimental study concerning corrosion effects on tensile behavior of RC members is presented. For this purpose, a comprehensive experimental program including 58 cylindrical reinforced concrete specimens under various levels of corrosion is conducted. Some of the specimens (44) are located in large tub containing water and salt (5% salt solution); an electrical supplier has been utilized for the accelerated corrosion program. Afterwards, the tensile behavior of the specimens was studied by means …
A Self-Tuning Controller For Real-Time Voltage Regulation, Weiming Li, Xiao-Hua Yu
A Self-Tuning Controller For Real-Time Voltage Regulation, Weiming Li, Xiao-Hua Yu
Electrical Engineering
In this research, a self-tuning controller based on multi-layer feed-forward neural network is developed for real-time output voltage regulation of a class of DC power supplies. The neural network based controller has the advantage of adaptive learning ability, and can work under the situations when the input voltage and load current fluctuate. Levenberg-Marquardt back-propagation training algorithm is used in computer simulation. The neural network controller is implemented and tested on hardware using a DSP (digital signal processor). Experimental results show that this neural network based approach outperforms the conventional analog controller, in terms of both line regulation and load regulation.
Flight Physician - August, 2007, Civil Aviation Medical Association
Flight Physician - August, 2007, Civil Aviation Medical Association
Browse all Civil Aviation Medical Association Newsletters
A sixteen page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.
Design Aids For Threaded Rod Precast Prestressed Girder Continuity System, Maher K. Tadros, Leslie D. Martin
Design Aids For Threaded Rod Precast Prestressed Girder Continuity System, Maher K. Tadros, Leslie D. Martin
Nebraska Department of Transportation: Research Reports
No abstract provided.
Flood Frequency Analysis Using Copula With Mixed Marginal Distributions, Subhankar Karmakar, Slobodan P. Simonovic
Flood Frequency Analysis Using Copula With Mixed Marginal Distributions, Subhankar Karmakar, Slobodan P. Simonovic
Water Resources Research Report
In flood frequency analysis, a flood event is mainly characterized by peak flow, volume and duration. These three variables or characteristics of flood are random in nature and mutually correlated. In this article, a methodology is developed to derive bivariate joint distributions of the flood characteristics using the concept of copula considering a set of parametric and nonparametric marginal distributions for peak flow, volume and duration to mathematically model the correlated nature among them. A set of parametric distribution functions, and nonparametric methods based on kernel density estimation and orthonormal series are used to determine the marginal distribution functions for …
Case Studies On Usage Of Axiomatic Design Methodology In The U.S. Industries, Alireza Alavizadeh
Case Studies On Usage Of Axiomatic Design Methodology In The U.S. Industries, Alireza Alavizadeh
All-Inclusive List of Electronic Theses and Dissertations
Axiomatic Design, originally developed by Nam Suh, is a design methodology that attempts to systematize the design practices and to provide a basis on which design can be carried out and optimized according to two main axioms, namely, Independence and Information axioms. Although various scholars in both academia and industry have studied the applicability and effectiveness of this methodology, the extent to which Axiomatic Design has been implemented in industry, particularly in the U.S., is unknown. l1l This study was conducted to identify the extent to which Axiomatic Design is known to the U.S. industries. Other purposes of this study …
Detection Of Aortic Calcification During Vertebral Fracture Assessment (Vfa) Compared To Digital Radiography, John T. Schousboe, Kevin E. Wilson, Thomas N. Hangartner
Detection Of Aortic Calcification During Vertebral Fracture Assessment (Vfa) Compared To Digital Radiography, John T. Schousboe, Kevin E. Wilson, Thomas N. Hangartner
Biomedical, Industrial & Human Factors Engineering Faculty Publications
Background: Cardiovascular disease is the most common cause of mortality among post-menopausal women. Our objective was to determine whether or not lateral spine images obtained on a bone densitometer to detect prevalent vertebral fracture can also accurately detect radiographic abdominal aortic calcification (AAC), an important risk factor for cardiovascular disease independent of clinical risk factors.
Methodology/Principal Findings: One hundred seventy four postmenopausal women had bone densitometry, lateral spine densitometry imaging (called vertebral fracture assessment, or VFA), and lateral spine digital radiographs. Radiographs and VFA images were scored for AAC using a previously validated 24 point scale and a simplified, …
Quantum Ballistics, Andrei Sokolov
Quantum Ballistics, Andrei Sokolov
Materials Research Science and Engineering Center: Faculty Publications
For the last 40 years, computer-chip manufacturers have been constantly improving the performance of their products by shrinking the size of transistors—the building blocks of processors and memory chips. Having gone from dimensions of a few microns in the early 1970s to 45 nm in Intel’s latest prototypes, the number of transistors that can be etched on a given area of silicon has been doubling every 18 months. This exponential trend, which is known as Moore’s law, has been the driving force behind the relentless miniaturization of microelectronic devices. However, we are now approaching the physical limits of existing technology. …
Towards A More Physically Adequate Definition Of Randomness: A Topological Approach, Vladik Kreinovich
Towards A More Physically Adequate Definition Of Randomness: A Topological Approach, Vladik Kreinovich
Departmental Technical Reports (CS)
Kolmogorov-Martin-Lof definition describes a random sequence as a sequence which satisfies all the laws of probability. This notion formalizes the intuitive physical idea that if an event has a probability 0, then this event cannot occur. Physicists, however, also believe that if an event has a very small probability, then it cannot occur. In our previous papers, we proposed a modification of the Kolmogorov-Martin-Lof definition which formalizes this idea as well. It turns out that our original definition is too general: e.g., it includes some clearly non-physical situations when the set of all random elements is a one-point set. In …
Towards Efficient Prediction Of Decisions Under Interval Uncertainty, Van Nam Huynh, Vladik Kreinovich, Yoshiteru Nakamori, Hung T. Nguyen
Towards Efficient Prediction Of Decisions Under Interval Uncertainty, Van Nam Huynh, Vladik Kreinovich, Yoshiteru Nakamori, Hung T. Nguyen
Departmental Technical Reports (CS)
In many practical situations, users select between n alternatives a1, ..., an, and the only information that we have about the utilities vi of these alternatives are bounds vi- <= vi <= v-+. In such situations, it is reasonable to assume that the values vi are independent and uniformly distributed on the corresponding intervals [vi-,vi+]. Under this assumption, we would like to estimate, for each i, the probability pi that the alternative ai will be selected. In this paper, we provide efficient algorithms for computing these probabilities.
Experimental Tuning Of Aifsn And Cwmin Parameters To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Experimental Tuning Of Aifsn And Cwmin Parameters To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Conference papers
In this paper we experimentally study the impact of two EDCA parameters, namely AIFSN and CWmin, on a mixed voice/data wireless transmission. In particular we investigate how the tuning of these parameters affects both the voice transmission quality and background data throughput. We predict end-to-end voice transmission quality from time varying transmission impairments using the latest Appendix to the ITU-T E-model. Our experimental results show that the tuning of the EDCA parameters can be used to successfully prioritize voice transmission over data in real 802.11e networks. We also demonstrate that the AIFSN parameter more effectively protects voice calls against background …
Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager
Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager
Material Science and Engineering Theses - Archive
Several undisclosed fiberglass and carbon fiber laminates with toughened resin systems were tested and examined. Experiments were conducted to determine Modes I and II interlaminar fracture toughness for each of the nine laminates with varying types of processing forms such as roving, tape, and slit tape of glass and carbon fibers. Fractography was then used to correlate the fracture toughness results with the unique characteristics and failure mechanisms. Overall, fiberglass laminates had larger interlaminar fracture toughness for both Modes I and II over the carbon laminates. This was also confirmed by the significant amount of the fractured surface area and …
Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure
Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure
Material Science and Engineering Theses - Archive
In the field of organic solar cell, the conjugated polymer-fullerene bulk heterojunction concept is one of the ongoing research interests. In this work, the use of de-oxyribose nucleic acid/ hexadecyl trimethyl ammonium chloride (DNA/CTMA) thin films as hole transport layer in poly(3-hexylthiophene)-methanofullerene (P3HT-PCBM) bulk heterojunction polymer solar cell is demonstrated. P3HT-PCBM bulk heterojunction polymer solar cell was fabricated with a DNA complex layer replacing commonly used PEDOT-PSS (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS). While PEDOT-PSS, as a hole transport and electron blocking layer, often improves the solar cell performance by improving fill factor, it requires careful engineering of spin-coating for the aqueous solution of …
Complete Stress Analysis For Two Dimensional Inclusion Problem Using Complex Variables, Rohan Arun Patil
Complete Stress Analysis For Two Dimensional Inclusion Problem Using Complex Variables, Rohan Arun Patil
Mechanical and Aerospace Engineering Theses - Archive
This thesis addresses the problem of finding stresses and displacements in an infinite plate with a two dimensional circular inclusion with different material properties using complex variable method with biaxial loading acting on it. The complex variable method is used so that the continuity equations of traction force and displacement field are satisfied at the interface .All the complex equations are solved using software Mathematica.
Stress Analysis Of An Ellipsoidal Inclusion, Mahesh Kailas
Stress Analysis Of An Ellipsoidal Inclusion, Mahesh Kailas
Mechanical and Aerospace Engineering Theses - Archive
The focus of the present thesis is to develop a mathematical model to calculate the stresses inside an ellipsoidal inclusion present in an infinitely extended matrix region and to validate the mathematically derived model by the Finite Element Method. To this end, a theoretical model has been developed to predict the stress inside an ellipsoidal inclusion. This model is based on equivalent inclusion method used to evaluate the stress distribution theoretically. Though there have been many theories to predict the stress distribution inside an ellipsoidal inclusion, its numerical validation is new despite its importance. A finite element model of a …
Exploratory Studies Of Convective Flows Due To Arc Tracking, Richard R. Mitchell
Exploratory Studies Of Convective Flows Due To Arc Tracking, Richard R. Mitchell
Mechanical and Aerospace Engineering Theses - Archive
The objective of the research was to develop an understanding of how a flame propagates through an electronic enclosure. FLUENT®, a Navier-Stokes solver, was chosen due to its widespread commercial use, the availability of turbulence models and its ability to handle combustion. The relevance of this study with respect to the aerospace and domestic appliance industry was shown through case reports. Initial observations were made on arc discharges, chemical compounds and their relevance to establishing the flame. Experimental bench tests highlighted the instigating factors for flame ignition. The first round of bench testing revealed that solder node separation played an …
Vehicular Emissions Models Using Mobile6.2 And Field Data, Abhishek Yerramalla
Vehicular Emissions Models Using Mobile6.2 And Field Data, Abhishek Yerramalla
Civil Engineering Theses - Archive
Regression models to predict vehicular emissions for different categories of vehicles for different pollutants are presented in this thesis. Vehicular emissions are affected by numerous variables which, among others, include speed, temperature, acceleration, deceleration, driving behavior and meteorological data. Regression models are developed based on data obtained from Mobile 6.2 and on-board emissions measurements. The U.S. Department of Transportation (US DOT) conducted sensitivity analysis of Mobile6 where they evaluated different parameters used to find the emission factors, such as vehicle miles traveled, speed, humidity, etc. The sensitivity analysis investigated the overall Mobile6.2 model behavior for various conditions. In the analysis, …
Large Array Emg Monitoring Of Lumbar Region Muscle Action In Discogenic Low Back Pain, Jazzmyne Ann Richardson Buckels
Large Array Emg Monitoring Of Lumbar Region Muscle Action In Discogenic Low Back Pain, Jazzmyne Ann Richardson Buckels
Bioengineering Theses - Archive
This project explored the use of large array surface electromyography (LASE) as a technique for assessing the patterns of muscular activity under standardized loading conditions in patients with lumbar disc related pain and healthy subjects. Specifically, the project evaluated quantitative parameters of visually observed patterns of muscle action proposed to clinically discriminate between groups. If such correlates exist, then, this work may lead to technology assessment for sensitivity and specificity as a diagnostic procedure. Solutions to the issues for determining the effects of low back pain (LBP) on force and moment generation in the spine as well as its effect …
A Functional Analysis Of The Mechanically And Metabolically Sensitive Components Of The Skeletal Muscle Exercise Pressor Reflex In Hypertension, Anna Katherine Leal
A Functional Analysis Of The Mechanically And Metabolically Sensitive Components Of The Skeletal Muscle Exercise Pressor Reflex In Hypertension, Anna Katherine Leal
Bioengineering Theses - Archive
Background - In hypertension, physical activity creates a risk for adverse cardiac events by causing exaggerated increases in mean arterial pressure (MAP) and heart rate (HR). One physiological mechanism responsible for this cardiovascular hyperactivity is the exercise pressor reflex (EPR). The EPR is a neural pathway originating in skeletal muscle that contributes to cardiovascular regulation during exercise. The EPR is composed of two afferent arms: one is comprised of mostly mechanically sensitive, group III afferent fibers that respond to muscle stretch and pressure, and the other is predominantly metabolically sensitive, group IV afferent fibers that respond to the chemical milieu …
Development Of A Broadband Multi-Channel Nirs System For Quantifying Absolute Concentrations Of Hemoglobin Derivatives And Reduced Scattering Coefficients, Dheerendra Kashyap
Development Of A Broadband Multi-Channel Nirs System For Quantifying Absolute Concentrations Of Hemoglobin Derivatives And Reduced Scattering Coefficients, Dheerendra Kashyap
Bioengineering Dissertations - Archive
Near infrared spectroscopy (NIRS) has been widely applied to investigate hemoglobin oxygenations of muscles, brain and breast tumors. Steady state reflectance techniques developed previously have been restricted to determination of relative concentrations. To overcome these limitations, this dissertation describes the development, validation and applications of broadband, steady-state, optical spectroscopic systems and algorithms to quantify absolute concentrations of hemoglobin derivatives and reduced light scattering coefficients using (1) thin optical probes with small (100 μm - 1 mm) source-detector separations and (2) a large separation (< 4 cm) probe.. A recently developed mathematical model by Zonios and Dimou for reflectance at small source-detector separations was used to develop techniques to quantify chromophore concentrations and light scattering coefficients (Chap. 2). Blood-intralipid phantom models were used to determine empirical coefficients to model reflectance spectra. This technique was further applied to quantify hemodynamic changes during formalin- induced pain behaviors in rats (Chap. 3). To overcome limitations in penetration depth and investigated tissue volume, another approach to quantify concentrations of chromophores in tissues at large source-detector separations was also developed. This novel approach uses the process of second differential spectroscopy to quantify concentrations of deoxygenated hemoglobin with respect to the tissue water content. Based on such quantification, an adaptation of the ant colony optimization algorithm was utilized to quantify absolute concentrations of other constituent tissue chromophores. The developed techniques were validated with the reflectance measurements from blood-intralipid phantoms and further applied to monitoring of ex vivo human prostate lesions and of rat brain tumor growth in vivo (Chap. 4). In the second stage of my doctoral development, a multi-channel, broadband, steady-state, NIRS imaging system was developed to determine spatial distributions of hemoglobin concentrations and reduced light scattering coefficients. The imager was calibrated with laboratory phantoms to eliminate deterministic instrumentation bias of CCD-spectrometers, optical fibers, and multiplexer channels. Calibration procedures also include determinations of the source strength and boundary coefficients in order to obtain accurate image reconstructions. A multi-wavelength, spectrally constrained reconstruction algorithm was developed to obtain tomographic maps of hemoglobin derivative concentrations and reduced scattering coefficients, using laboratory tissue phantoms. The developed imaging system and reconstruction algorithms were validated with both static and dynamic multi-tube phantoms.
Resolution And Localization In Single Molecule Microscopy, Sripad Ram
Resolution And Localization In Single Molecule Microscopy, Sripad Ram
Bioengineering Dissertations - Archive
Rayleigh's criterion is extensively used in optical microscopy to determine the resolution of microscopes. Despite its widespread use, it is well known that this criterion is based on heuristic notions and can be surpassed in a regular optical microscope. The inadequacy of Rayleigh's criterion has necessitated a reassessment of the resolution limits of optical microscopes. The thesis proposes a new resolution criterion that overcomes the limitations of Rayleigh's criterion. The new result predicts that there is no resolution limit, but that the resolvability depends on the number of detected photons. Analytical tools are introduced to estimate the distance from microscopy …