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Naked Object File System (Nofs): A Framework To Expose An Object-Oriented Domain Model As A File System, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal 2011 Loyola University Chicago

Naked Object File System (Nofs): A Framework To Expose An Object-Oriented Domain Model As A File System, Joseph P. Kaylor, Konstantin Läufer, George K. Thiruvathukal

George K. Thiruvathukal

We present Naked Objects File System (NOFS), a novel framework that allows a developer to expose a domain model as a file system by leveraging the Naked Objects design principle. NOFS allows a developer to construct a file system without having to understand or implement all details related to normal file systems development. In this paper we explore file systems frameworks and object-oriented frameworks in a historical context and present an example domain model using the framework. This paper is based on a fully-functional implementation that is distributed as free/open source software, including virtual machine images to demonstrate and study …


Improving The Ductility Of Knee Joints Between Rectangular Hollow Sections, Lip H. Teh, Gregory J. Hancock 2011 University of Wollongong

Improving The Ductility Of Knee Joints Between Rectangular Hollow Sections, Lip H. Teh, Gregory J. Hancock

Lip H. Teh

This paper proposes a new welding-based solution that significantly increases the rotation capacity of a stiffened welded knee joint between cold-formed rectangular hollow sections under opening moment. The proposed solution is more economical than the use of internal sleeves and can be applied to new as well as existing structures. The solution involves the use of extra layers of weld on the inner (tension) flange of a stiffened welded knee joint. Laboratory test results are presented to demonstrate that the solution enabled such a joint between DuraGal C450 150×50×4 or 150×50×5 rectangular hollow sections manufactured to AS 1163 to satisfy …


Beam Element Verification For 3d Elastic Steel Frame Analysis, Lip H. Teh 2011 University of Wollongong

Beam Element Verification For 3d Elastic Steel Frame Analysis, Lip H. Teh

Lip H. Teh

The paper describes the attributes that should be possessed by a benchmark example for verifying the beam elements used to carry out 3D linear buckling analysis and 3D second-order elastic analysis of steel frames. Based on the attributes described, the paper proposes a suite of benchmark examples selected from the literature. The necessary features of a beam element required to pass the proposed benchmark problems are given, and beam elements that possess these features are cited. The paper also explains the merits of linear buckling analysis examples, and provides a commentary on two well-known examples.


Cubic Beam Elements In Practical Analysis And Design Of Steel Frames, Lip H. Teh 2011 University of Wollongong

Cubic Beam Elements In Practical Analysis And Design Of Steel Frames, Lip H. Teh

Lip H. Teh

This paper discusses various issues in the use of cubic beam elements for computer structural analysis/design of steel frames. It is pointed out that the concern expressed in recent literature regarding the number of cubic elements required to model a steel member is not justified, and that the inaccuracy of one cubic element in Euler buckling analysis of a simply supported column is largely irrelevant to the second-order elastic analysis/design or advanced analysis of steel frames. The sources of inaccuracy of the cubic element are elucidated. It is also explained that the plastic-zone analysis method is not so inefficient as …


Second-Order Moments In Torsion Members, Nicholas S. Trahair, Lip H. Teh 2011 University of Sydney

Second-Order Moments In Torsion Members, Nicholas S. Trahair, Lip H. Teh

Lip H. Teh

This paper is concerned with the elastic flexural buckling of structural members under torsion, and with second-order moments in torsion members. Previous research is reviewed, and the energy method of predicting elastic buckling is presented. This is used to develop the differential equilibrium equations for a buckled member. Approximate solutions based on the energy method are obtained for a range of conservative applied torque distributions and flexural boundary conditions. A comparison with the limited range of independent solutions available and with independent finite element solutions suggests that the errors in the approximate solutions may be as small as 1%. The …


Analysis And Design Of Double-Sided High-Rise Steel Pallet Rack Frames, Lip H. Teh, Gregory J. Hancock, Murray J. Clarke 2011 University of Wollongong

Analysis And Design Of Double-Sided High-Rise Steel Pallet Rack Frames, Lip H. Teh, Gregory J. Hancock, Murray J. Clarke

Lip H. Teh

In routine design of steel storage rack frames, it is far more common to perform two dimensional (2D) rather than three dimensional (3D) linear buckling analyses. In this paper, it is demonstrated that the global buckling behavior of high-rise steel storage rack frames may not be revealed by 2D buckling analyses as 3D interaction modes are involved. It is shown that the monosymmetric upright columns of a high-rise rack frame fail in a flexural–torsional mode due to the shear-center eccentricity of the sections, and that the 3D frame buckling analysis is more reliable in determining the critical members of a …


Spatial Rotation Kinematics And Flexural-Torsional Buckling, Lip H. Teh 2011 University of Wollongong

Spatial Rotation Kinematics And Flexural-Torsional Buckling, Lip H. Teh

Lip H. Teh

This paper aims to clarify the intricacies of spatial rotation kinematics as applied to three-dimensional (3D) stability analysis of metal framed structures with minimal mathematical abstraction. In particular, it discusses the ability of the kinematic relationships traditionally used for a spatial Euler–Bernoulli beam element, which are expressed in terms of transverse displacement derivatives, to detect the flexural–torsional instability of a cantilever and of an L-shaped frame. The distinction between transverse displacement derivatives and vectorial rotations is illustrated graphically. The paper also discusses the symmetry and asymmetry of tangent stiffness matrices derived for 3D beam elements, and the concepts of semitangential …


Causes Of The Blackout: The Grid Operation And Environment, Almoataz Youssef Abdelaziz 2011 Electrical Power & Machines Department, Faculty of Engineering, Ain Shams University

Causes Of The Blackout: The Grid Operation And Environment, Almoataz Youssef Abdelaziz

Almoataz Youssef Abdelaziz

Despite huge advancements in different power system components, operations, and protection technologies, todayÕs power systems are more vulnerable to blackouts than ever before. Deregulation, market competition, and increasing demands, in addition to less investment in transmission assets, all contribute to the critical state power systems operate at. Two main characteristics of the power system are always being put under the scope of study, reliability and security. This paper takes a subjective thorough look at the previous numerous blackout events, surveyed by the authors, that have been encountered by different power systems around the globe and classifies them into different types …


Directed Evolution Of Adeno-Associated Virus For Enhanced Gene Delivery And Gene Targeting In Human Pluripotent Stem Cells, Prashanth Asuri, Melissa Bartel, Tandis Vazin, Jae-Hyung Jang, Tiffany Wong, David Schaffer 2011 Santa Clara University

Directed Evolution Of Adeno-Associated Virus For Enhanced Gene Delivery And Gene Targeting In Human Pluripotent Stem Cells, Prashanth Asuri, Melissa Bartel, Tandis Vazin, Jae-Hyung Jang, Tiffany Wong, David Schaffer

Bioengineering

Efficient approaches for the precise genetic engineering of human pluripotent stem cells (hPSCs) can enhance both basic and applied stem cell research. Adenoassociated virus (AAV) vectors are of particular interest for their capacity to mediate efficient gene delivery to and gene targeting in various cells. However, natural AAV serotypes offer only modest transduction of human embryonic and induced pluripotent stem cells (hESCs and hiPSCs), which limits their utility for efficiently manipulating the hPSC genome. Directed evolution is a powerful means to generate viral vectors with novel capabilities, and we have applied this approach to create a novel AAV variant with …


Ceas E-News 11.22.2011, College of Engineering and Applied Sciences 2011 Western Michigan University

Ceas E-News 11.22.2011, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

Stryker Challenge Team Win, Student Team and Alumni Accelerate Michigan Win, ProModel Team Win, Workshop, Roundtable, SWE Event, Make a Difference


A Time-Efficient Method For Accurate T1 Mapping Of The Human Brain, Yung-Yeh Chang 2011 Virginia Commonwealth University

A Time-Efficient Method For Accurate T1 Mapping Of The Human Brain, Yung-Yeh Chang

Theses and Dissertations

The signal resulting from the IR-FSE sequence has been thoroughly analyzed in order to improve the accuracy of quantitative T1 mapping of the human brain. Several optimized post-processing algorithms have been studied and compared in terms of their T1 mapping accuracy. The modified multipoint two-parameter fitting method was found to produce less underestimation compared to the traditional multipoint three-parameter fitting method, and therefore, to result in a smaller T1 estimation error. Two correction methods were proposed to reduce the underestimation problem which is commonly seen in IR-FSE sequences used for measuring T1, especially when a large turbo factor is used. …


Investigations Of Transesterification Of Canola Oil With Methanol And Ethanol For A New Efficient Method Of Biodiesel Production, Krupal Pal 2011 The University of Western Ontario

Investigations Of Transesterification Of Canola Oil With Methanol And Ethanol For A New Efficient Method Of Biodiesel Production, Krupal Pal

Electronic Thesis and Dissertation Repository

Transesterification of vegetable oil to biodiesel is a multistep process affected by mass transfer, mixing and chemical reaction equilibrium. Attempts have been made in this study to overcome these limitations by gradually feeding oil into a pool of alcohol. This approach provided large excess of alcohol to allow reaction to proceed further as well as allowed easy dispersion of oil into the alcohol. As a result improved conversion of feed, higher yield and better product quality were achieved. Comparisons have been made with other methods to show the differences and highlight improvements. Reactions were conducted at various reaction conditions for …


Interconnection Of Oman And Uae Electric Power Systems, Omar H. Abdalla, Rashid Al-Badwawi, Hilal S. Al-Hadi, Hisham A. Al-Riyami, Ahmed Al-Nadabi, Karim Karoui, Ariadne Szekut 2011 University of Helwan

Interconnection Of Oman And Uae Electric Power Systems, Omar H. Abdalla, Rashid Al-Badwawi, Hilal S. Al-Hadi, Hisham A. Al-Riyami, Ahmed Al-Nadabi, Karim Karoui, Ariadne Szekut

Omar H. Abdalla

The objective of this paper is to assess the impact of interconnecting Oman and United Arab Emirates (UAE) through the existing 220kV, 46.7km double circuit transmission line rated 762MVA for each circuit. A model is developed to represent both systems of Oman and UAE based on the EUROSTAG© software. Load flow and contingency studies are presented to evaluate the compliance of the interconnected system for security criteria N and N-1. Calculations are applied to two operating conditions (peak and minimum load) and for three energy exchange cases: no exchange and maximum exchanges in both directions. Short circuit studies are presented …


Power Control And Security Games For Wireless Communication Networks, Bo Liang 2011 University of Nebraska-Lincoln

Power Control And Security Games For Wireless Communication Networks, Bo Liang

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

In this thesis, game theoretic analysis of wireless communication networks has been performed. Game theory provides valuable tools can be used to solve problem of conflict and cooperation in wireless communication networks. Game theoretic tools can be applied to multiple layers of wireless networks. First, we consider power control issues at the physical layer of wireless networks. A game theoretic analysis for resource allocation policies in fading interference channels in the presence of quality of service (QoS) constraints is performed. We model a two player non-cooperative power control game and assume that both transmitters and receivers know the channel side …


One-Step Infiltration Of Mixed Conducting Electrocatalysts For Reducing Cathode Polarization Of A Commercial Cathode-Supported Sofc, Nansheng Xu, Xue Li, Xuan Zhao, Hailei Zhao, Kevin Huang 2011 University of South Carolina - Columbia

One-Step Infiltration Of Mixed Conducting Electrocatalysts For Reducing Cathode Polarization Of A Commercial Cathode-Supported Sofc, Nansheng Xu, Xue Li, Xuan Zhao, Hailei Zhao, Kevin Huang

Faculty Publications

Infiltrating fine-grained electrocatalyst particles of either ion conducting or mixed electron and ion conducting (MEIC) material into a ceramic porous electrode scaffold has proven a very effective way to improve electrode performance for low to intermediate temperature solid oxide fuel cells (SOFCs). We report here one-step infiltration of MEIC fine particles, La0.6Sr0.4CoO3-δ (LSCo) and SrCo0.8Fe0.2O3-δ (SCF), into a commercial cathode substrate. A comparative study shows that the cathode polarization can be considerably reduced by a factor of 17 to 28 and 28 to 49 from 1000 to 700 ³C by …


Bonding Of Polydimethylsiloxane Microfluidics To Silicon-Based Sensors, Long-Fang Tsai, William C. Dahlquist, Seunghyun Kim, Gregory P. Nordin 2011 University of Alabama in Huntsville

Bonding Of Polydimethylsiloxane Microfluidics To Silicon-Based Sensors, Long-Fang Tsai, William C. Dahlquist, Seunghyun Kim, Gregory P. Nordin

Faculty Publications

We investigate bonding polydimethylsiloxane (PDMS) to silicon using a thin (~2μm) intermediate adhesive layer stamped onto a PDMS piece prior to bonding. In particular, we compare as adhesive layers Sylgard 184 and 182 curing agents and a UV curable adhesive (NOA 75). We examine the effect of both curing temperature and duration on curing agent bond strength. Bond strengths for the different adhesives are determined by measuring the average burst pressure at a PDMS-silicon interface using a PDMS test design. We find that Sylgard 184 curing agent gives the highest bond strength with burst pressure of 700 kPa or more …


Circular And Near-Circular Polarization States Of Evanescent Monochromatic Light Fields In Total Internal Reflection, R. M. A Azzam 2011 University of New Orleans

Circular And Near-Circular Polarization States Of Evanescent Monochromatic Light Fields In Total Internal Reflection, R. M. A Azzam

Electrical Engineering Faculty Publications

Conditions for the production of near-circular polarization states of the evanescent field present in the rarer medium in total internal reflection of incident monochromatic p-polarized light at a dielectric-dielectric planar interface are determined. Such conditions are satisfied if high-index (>3.2) transparent prism materials (e.g., GaP and Ge) are used at angles of incidence well above the critical angle but sufficiently below grazing incidence. Furthermore, elliptical polarization of incident light with nonzero p and s components can be tailored to cause circular polarization of the resultant tangential electric field in the plane of the interface or circular polarization of the …


Efficient Database Generation For Decision Tree Based Power System Security Assessment, Venkat Krishnan 2011 Iowa State University

Efficient Database Generation For Decision Tree Based Power System Security Assessment, Venkat Krishnan

Venkat Kumar Krishnan

No abstract provided.


Determination Of Isotherms Of Enantiomers On A Chiral Stationary Phase Using Supercritical Fluid Chromatography, Wade Newlin Mack Ii 2011 University of South Florida

Determination Of Isotherms Of Enantiomers On A Chiral Stationary Phase Using Supercritical Fluid Chromatography, Wade Newlin Mack Ii

USF Tampa Graduate Theses and Dissertations

Supercritical fluids provide a robust, tunable environment with favorable transport properties and enhanced solubility. Supercritical carbon dioxide is an environmentally friendly substance that has distinct advantages to traditional solvents used in large scale chemical processing. Ibuprofen is an enantiomeric drug that has been shown to fight prostate cancer and has been used as a mild Alzheimer's disease treatment in the S conformation. Purification of high value products with decreased hazardous material consumption is accomplished by employing supercritical fluid chromatography (SFC). Large scale, single enantiomer purification of pharmaceuticals is dependent on scale-up information. Equilibrium isotherms provide the necessary information to scale-up …


High Speed And Low-Complexity Hardware Architectures For Elliptic Curve-Based Crypto-Processors, Reza Azarderakhsh 2011 University of Western Ontario

High Speed And Low-Complexity Hardware Architectures For Elliptic Curve-Based Crypto-Processors, Reza Azarderakhsh

Electronic Thesis and Dissertation Repository

The elliptic curve cryptography (ECC) has been identified as an efficient scheme for public-key cryptography. This thesis studies efficient implementation of ECC crypto-processors on hardware platforms in a bottom-up approach. We first study efficient and low-complexity architectures for finite field multiplications over Gaussian normal basis (GNB). We propose three new low-complexity digit-level architectures for finite field multiplication. Architectures are modified in order to make them more suitable for hardware implementations specially focusing on reducing the area usage. Then, for the first time, we propose a hybrid digit-level multiplier architecture which performs two multiplications together (double-multiplication) with the same number of …


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