Engineering Commons^™

Agen Bola Terpercaya Warung757.Net, Defaonline Blog

defaonline blog

The Ilo And The Regulation Of White Lead In Britain During The Interwar Years: An Examination Of International And National Campaigns In Occupational Health, John Alfred Heitmann

John A. Heitmann

Despite the International Labour Organization's (ILO) significance for much of the twentieth century, little has been written on its early history. This case study examines the thin tightrope that the ILO had to walk in balancing the needs and demands of government, employers and labor related to the ILO's Convention No. 13 (1921), "White Lead in Painting.' Great Britain was a leading producer of the pigment white lead prior to the First World War. A government investigation was published in 1915, but measures were shelved during the War. With the peace, the focus of activity shifted to the ILO.

Preparations …

Doing 'True Science': The Early History Of The 'Institutum Divi Thomae,' 1935-1951, John Alfred Heitmann

John A. Heitmann

This essay focuses on the origins and early history of the Institutum Divi Thomae (hereafter referred to as the IDT or Institutum), thus describing one particularly rich episode illustrating the relationship between American Catholicism and science during the middle of the twentieth century. The IDT was established by the Archdiocese of Cincinnati in 1935; its faculty and students, while working in the area of cancer research, published hundreds of scientific and technical papers, developed a number of commercial products, and received considerable publicity in both the religious and secular press during the first two decades of its existence. However, with …

Role Of Diffusive, Photovoltaic, And Thermal Effects In Beam Fanning In Linbo3, Jaw-Jueh Liu, Partha P. Banerjee, Q. W. Song

Partha Banerjee

We analyze the steady-state (Gaussian) beam fanning in LiNbO3 from the nonlinearly coupled Kukhtarev equations by including both diffusive and photovoltaic effects and by adding the thermal effect in the calculation. There is good agreement between theory and experiment. The results show a symmetric beam-fanning pattern whose size depends on the beam waist and the power. Possible applications of our results in nondestructive testing of material parameters and optical limiting are discussed.

Simulation Of Two-Dimensional Nonlinear Envelope Pulse Dynamics By A Two-Step Spatiotemporal Angular Spectrum Method, H. K. Sim, Adrianus Korpel, Karl E. Lonngren, Partha P. Banerjee

Partha Banerjee

We present an extension of our previous nonlinear beam-simulation method to the propagation and interaction of pulse envelopes. The extra time dimension is applied in the context of a dispersive nonlinear medium that is described by a Klein–Gordon equation with an added cubically nonlinear, self-focusing term. Pulse propagation in this medium is modeled as the evolution of a spatiotemporal spectrum—i.e., the frequency-dependent angular spectrum of the pulse envelope—traversing a sequence of self-induced, thin, weak phase filters. Preliminary simulation experiments show agreement with known behavior in the absence of nonlinearity, confirm the existence of an (apparently unstable) stationary solution, and demonstrate …

Theoretical And Experimental Studies Of Propagation Of Beams Through A Finite Sample Of A Cubically Nonlinear Material, Partha P. Banerjee, Raj M. Misra, M. Maghraoui

Partha Banerjee

Propagation of an externally focused or defocused Gaussian beam in a cubically nonlinear material is studied analytically and experimentally. The theoretical analysis is applied to determine the sign and magnitude of n2 for a material by means of a single-beam experiment with a finite nonlinear sample within which propagational diffraction cannot be neglected. Experimental results for a solution of chlorophyll in ethanol are reported. Based on available theory, an average n2 can be defined for a nonlinearity of thermal origin, and this value is found to be in good agreement with experimental results. Finally, the theoretical analysis and …

On A Simple Derivation Of The Fresnel Diffraction Formula And A Transfer Function Approach To Wave Propagation, Partha P. Banerjee, Ting-Chung Poon

Partha Banerjee

The Fresnel diffraction formula is straightforwardly obtained by solving a partial differential equation (PDE) for envelope propagation using Fourier transform techniques. The PDE, in turn, can be derived from the dispersion relation of a linear medium by employing a simple operator formalism. The transfer function and impulse response of propagation follows as a spin‐off and is used to solve illustrative problems. Huygens’ principle is visualized as a consequence of the convolution property of linear systems.

Notch Spatial Filtering With An Acousto-Optic Modulator, Partha P. Banerjee, Dongqing Cao, Ting-Chung Poon

Partha Banerjee

The role of acousto-optic (AO) modulators in programmable real-time image processing has recently been demonstrated. For fully investigating the image-processing capabilities of the AO modulator, general techniques to derive spatial transfer functions are needed for a variety of physical situations. We develop a technique to determine the spatial transfer functions numerically for various cases of beam incidence on an AO modulator. Normal incidence and incidence at twice the Bragg angle are investigated as examples for which double-sided and single-sided notch spatial filtering, respectively, are achieved. The observed spatial-filtering characteristics are reconciled with simple intuitive physical arguments.

Nonlinear Transverse Effects In Second-Harmonic Generation, Pawel Pliszka, Partha P. Banerjee

Partha Banerjee

We study a three-dimensional model of interaction of fundamental-frequency and second-harmonic beams in a quadratically nonlinear medium. Numerical simulations of the three-dimensional propagation problem in the presence of diffraction and anisotropy are performed under the paraxial approximation. The role of the transverse effects in various regimes is investigated. We demonstrate the effect of phase modulation and an induced nonlinear focusing during the interaction of the fundamental frequency with the generated second harmonic.

Multiwave Coupling In A High-Gain Photorefractive Polymer, Kenji Matsushita, Partha P. Banerjee, S. Ozaki, Daisuke Miyazaki

Partha Banerjee

The characteristics of a new high-gain photorefractive polymer composite with a PNP chromophore are investigated. Competition between beam fanning and two-wave coupling (TWC) is predicted and verified experimentally. The intensity dependence of TWC gain is studied. Higher diffraction order and forward phase conjugation in a TWC geometry are observed and explained.

Linear And Nonlinear Propagation In Negative Index Materials, Partha P. Banerjee, George Nehmetallah

Partha Banerjee

We analyze linear propagation in negative index materials by starting from a dispersion relation and by deriving the underlying partial differential equation. Transfer functions for propagation are derived in temporal and spatial frequency domains for unidirectional baseband and modulated pulse propagation, as well as for beam propagation. Gaussian beam propagation is analyzed and reconciled with the ray transfer matrix approach as applied to propagation in negative index materials. Nonlinear extensions of the linear partial differential equation are made by incorporating quadratic and cubic terms, and baseband and envelope solitary wave solutions are determined. The conditions for envelope solitary wave solutions …

Application Of Up-Sampling And Resolution Scaling To Fresnel Reconstruction Of Digital Holograms, Logan Williams, George Nehmetallah, Rola Aylo, Partha P. Banerjee

Partha Banerjee

Fresnel transform implementation methods using numerical preprocessing techniques are investigated in this paper. First, it is shown that up-sampling dramatically reduces the minimum reconstruction distance requirements and allows maximal signal recovery by eliminating aliasing artifacts which typically occur at distances much less than the Rayleigh range of the object. Second, zero-padding is employed to arbitrarily scale numerical resolution for the purpose of resolution matching multiple holograms, where each hologram is recorded using dissimilar geometric or illumination parameters. Such preprocessing yields numerical resolution scaling at any distance. Both techniques are extensively illustrated using experimental results.

Achieving Enhanced Gain In Photorefractive Polymers By Eliminating Electron Contributions Using Large Bias Fields, C. M. Liebig, S. H. Buller, Partha P. Banerjee, S. A. Basun, Pierre-Alexandre Blanche, J. Thomas, Cory W. Christenson, N. Peyghambarian, Dean R. Evans

Partha Banerjee

Photorefractive polymers have been extensively studied for over two decades and have found applications in holographic displays and optical image processing. The complexity of these materials arises from multiple charge contributions, for example, leading to the formation of competing photorefractive gratings. It has been recently shown that in a photorefractive polymer at relatively moderate applied electric fields the primary charge carriers (holes) establish an initial grating, followed by a subsequent competing grating (electrons) resulting in a decreased two-beam coupling and diffraction efficiencies. In this paper, it is shown that with relatively large sustainable bias fields, the two-beam coupling efficiency is …

3d Visualization Using Pulsed And Cw Digital Holographic Tomography Techniques, George Nehmetallah, Partha P. Banerjee, D. Ferree, R. Kephart, Sarat C. Praharaj

Partha Banerjee

We outline the use of digital holographic tomography to determine the three-dimensional (3D) shapes of falling and static objects, such as lenslets and water droplets. Reconstruction of digitally recorded inline holograms is performed using multiplicative and Radon transform techniques to reveal the exact 3D shapes of the objects.

A Comprehensive Optimized Model For On-Board Solar Photovoltaic System For Plug-In Electric Vehicles: Energy And Economic Impacts, Mahmoud M. Abdelhamid

Mahmoud M Abdelhamid

Computer-Assisted Learning Based On Universal Design, Multimodal Presentation And Textual Linkage, Leyla Zhuhadar

Leyla Zhuhadar

The Effect Of Preceptor Role Effectiveness On Newly Licensed Registered Nurses' Perceived Psychological Empowerment And Professional Autonomy, Channell Watkins, Patricia Hart, Nicole Mareno

Nicole Mareno

An Ontology And Integration Framework For Smart Communities, Steven Ray, Shishir Kinkar, Mark Hennessy

Steven R Ray

The Effects Of Transitioning From A Face-To-Face Fundamentals Of Engineering Review To A Virtual Environment, Mohammad Biswas

Mohammad Biswas

Guidelines For Using Process Mapping To Aid Improvement Efforts, Paul Savory, John Olson

John Olson

Process mapping is an easy-to-visualize method for people to analyze and agree on the most efficient routes for reengineering or improving a process. It aids in determining redundant tasks, uncovering hidden interactions between processes and people, and focusing on the processes that serve customers, improve quality, and generate income. This paper presents guidelines for using process mapping as an improvement tool. It is based on the authors’ experiences in aiding a variety of healthcare, service, and manufacturing companies.

A New Saifi Based Voltage Sag Index, Robert Barr, V. Gosbell, Ian Mcmichael

Robert Barr

Reliability measures of SAIDI (system average interruption duration index) and SAIFI (system average frequency index) are well established industry standards used world wide. While both measures have their limitations, they give a broad indication of average reliability that allows comparison within networks and across networks world wide. No such industry standard indices exist for voltage sags. The main reason being that voltage sags are multi-dimensional, involving retained sag voltage, sag duration, number of phases effected, phase angle jumps and the time between successive sags. This paper proposes a new voltage sag index that is dimensionally the same as SAIFI having …

Preliminary Evaluations On Laser - Tandem Gmaw, Ruham Reis, John Norrish, Dominic Cuiuri

Dominic Cuiuri

Recently there has been considerable research and development activity in the use of lasers for welding operations, turning this process into an important tool for a variety of applications. Although it is possible to use lasers as a unique source of heat to promote union of materials, the combination of the beam provided by a laser system with an arc welding process has been studied widely and applied in the so-called hybrid welding systems. Generally, the final result of such a combination is an increase in the weld penetration depth, width and welding travel speed. Despite these advantages, there are …

Cracking The Shell To Student Learning: An Innovative Instructional Approach, John Olson, Paul Savory

John Olson

Management and Industrial Engineering courses is motivating students to learn and apply the quantitative and managerial aspects of the material. The aim of our educational methodology is to not only teach and reinforce the core principles of the disciplines, but to have students develop a set of skills that will make them competitive in the classroom and the workforce. Teaching is why a university exists. As a result, the objective of our instructional approach is to attract and retain dedicated students to the fields of Operations Management and Industrial Engineering and to keep those students competitive and in focus with …

Road Rescue Implements A Continuous Process Improvement Framework, John Olson, Paul Savory

John Olson

Continuous improvement programs traditionally focus on making small incremental improvements to a system. Unfortunately, their success can be limited due to the rapid changing environment within which most small companies operate. Improvement efforts should be flexible enough to capitalize on incremental and radical changes to a system. This paper presents a case analysis of how Road Rescue, an ambulance manufacturer, uses a continuous improvement framework to capitalize on both radical and incremental improvement opportunities. Results include a 10% increase in throughput, reduced cycle time of 44%, increased customer satisfaction, and higher quality.

Constrained Biogeography-Based Optimization For Invariant Set Computation,, Arpit Shah, Daniel Simon, Hanz Richter

Hanz Richter

We discuss the application of biogeography-based optimization (BBO) to invariant set approximation. BBO is a recently developed evolutionary algorithm (EA) that is motivated by biogeography, which is the study and science of the geographical migration of biological species. Invariant sets are sets in the state space of a dynamic system such that if the state begins in the set, then it remains in the set for all time. Invariant sets have applications in many constrained control problems, and their computation amounts to a constrained optimization problem. We therefore frame the invariant set computation problem as a constrained optimization problem, and …

Discovery Of Design Methodologies, Cirrus Shakeri, David Brown, Mohammad Noori

David C. Brown

In this paper we present an AI-based approach for the discovery of design methodologies for multi-disciplinary design situations. The approach is based on simulating the design process using a multi-agent system that mimics the behavior of the design team. The system activates the pieces of design knowledge when they become applicable. The use of knowledge by agents is recorded by tracing the steps that the agents have taken during a design project. Many traces are generated by solving a large number of design projects that differ in their requirements. A set of design methodologies is constructed by using clustering techniques …

Combining Dynamic Stretch And Tunable Stiffness To Probe Cell Mechanobiology In Vitro, Angela Quinlan, Leslie Sierad, Andrew Capulli, Laura Firstenberg, Kristen Billiar

Kristen L. Billiar

Cells have the ability to actively sense their mechanical environment and respond to both substrate stiffness and stretch by altering their adhesion, proliferation, locomotion, morphology, and synthetic profile. In order to elucidate the interrelated effects of different mechanical stimuli on cell phenotype in vitro, we have developed a method for culturing mammalian cells in a two-dimensional environment at a wide range of combined levels of substrate stiffness and dynamic stretch. Polyacrylamide gels were covalently bonded to flexible silicone culture plates and coated with monomeric collagen for cell adhesion. Substrate stiffness was adjusted from relatively soft (G' = 0.3 kPa) to …

A Framework For Control Of Robots With Energy Regeneration, Hanz Richter

Hanz Richter

This paper focuses on robot control problems where energy regeneration is an explicit consideration, and it proposes a methodology for modeling and control design of regenerative motion control systems. The generic model consists of a robotic manipulator where some joints are actively controlled and the remaining joints are energetically self-contained and semi-actively controlled. The model can capture various electromechanical and hydraulic actuator configurations for industrial robots and powered human-assist devices. The basic control approach consists of three steps. First, a virtual control design is conducted by any suitable means. Then, virtual control inputs are enacted by a matching law for …

Thermodynamic Method For Prediction Of Surfactant Modified Oil Droplet Contact Angle, Samuel Morton, David Keffer, R. Counce, D. Depaoli, M. Hu

Samuel A Morton

A model applying surfactant self-assembly theory and classical thermodynamics has been developed to aid in the prediction of solid surface cleaning by aqueous surfactant solutions. Information gained from a combination of surfactant self-assembly behavior and cleaning system parameters, such as oil species, surfactant type, temperature, alkalinity, and solid surface type has been shown to provide insight into surface cleaning. The model combines minimization of free energy, pertinent component distribution mechanisms, and surfactant self-assembly processes to provide a methodology for the predicting of oil droplet contact angles. Such predictive capabilities will allow for the development of beneficial environmental and economic changes …

A Flexible Approach To On-Site Power Filtering And Supply Backup Using High Capacity High Temperature Smes For Maximum Equipment Utility, Dominic Cuiuri, Jeffrey Moscrop, Christopher Cook

Dominic Cuiuri

With power systems subject to an ever-increasing variety of load types, power quality remains of concern to both utilities and consumers alike. Some of the most concerning issues to users of sensitive equipment include voltage sags, supply interruption and current harmonics. This paper describes a comprehensive power quality device that can be designed to compensate for harmonic load currents and mains voltage variations in a system, as well as providing mains failure backup for smaller critical system loads. The design process described integrates high capacity high temperature Superconducting Magnetic Energy Storage (SMES) technology with Active Power Filter (APF) switching technology …