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Full-Text Articles in Engineering
Road Rescue Implements A Continuous Process Improvement Framework, John Olson, Paul Savory
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.
Geometric And Operational Improvements At Continuous Flow Intersections To Enhance Pedestrian Safety, Angela Coates, Ping Yi, Peng Liu, Xinlu Ma
Geometric And Operational Improvements At Continuous Flow Intersections To Enhance Pedestrian Safety, Angela Coates, Ping Yi, Peng Liu, Xinlu Ma
Ping Yi
Traditional four-phase, four-legged intersections may operate inefficiently under high traffic demand. Innovative geometric design configurations for intersections allow more efficient traffic operations and can significantly increase vehicle throughput. Continuous flow intersections (CFIs), also referred to as displaced left-turn intersections, use an unconventional lane arrangement to maximize the vehicular throughput. This arrangement involves displacing left-turn lanes across opposing through traffic before reaching the main intersection. Such an alteration allows left-turning and through vehicles to proceed simultaneously, and both intersection capacity and delay are improved as a result. Numerous studies have validated these operational improvements, but pedestrian accommodation often is low because …
Multi-Barge Flotilla Impact Forces On Bridges, Peng Yuan, Issam Harik, Michael Davidson
Multi-Barge Flotilla Impact Forces On Bridges, Peng Yuan, Issam Harik, Michael Davidson
Issam E. Harik
The current AASHTO equations for barge impact loads are based on scale models of barges, and may not accurately predict impact loads on bridge piers. The results of this study produce more realistic flotilla impact design loads, potentially leading to a reduction in construction costs of bridges over navigable waterways. The objectives of this study are: (1) To conduct theoretical finite element analysis on various types of flotillas impacting bridge piers. The flotillas and the respective barges will be of the type commonly traversing Kentucky’s waterways; and (2) To generate design equations for barge/flotilla impact loads. The study concludes the …
Equivalent Barge And Flotilla Impact Forces On Bridge Piers, Peng Yuan, Issam Harik
Equivalent Barge And Flotilla Impact Forces On Bridge Piers, Peng Yuan, Issam Harik
Issam E. Harik
Bridge piers located in navigable inland waterways are designed to resist impact forces from barges and flotillas in addition to other design considerations (e.g., scour, dead and live loads, etc.). The primary design tool for estimating these forces is the AASHTO Guide Specification which provides a simple hand calculation method for determining an “equivalent impact force”. The simplicity comes at a cost of excluding the effect of the pier shape, impact duration, and interaction between barges in a flotilla. The objective of this report is to present a hand calculation method for determining barge or flotilla equivalent static impact forces …
Laser Assisted Embedding Of Nanoparticles Into Metallic Materials, Dong Lin, Sergey Suslov, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng
Laser Assisted Embedding Of Nanoparticles Into Metallic Materials, Dong Lin, Sergey Suslov, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng
Dr. Chang Ye
This paper reports a methodology of half-embedding nanoparticles into metallic materials. Transparent and opaque nanoparticles are chosen to demonstrate the process of laser assisted nanoparticle embedding. Dip coating method is used to coat transparent or opaque nanoparticle on the surface of metallic material. Nanoparticles are embedded into substrate by laser irradiation. In this study, the mechanism and process of nanoparticle embedding are investigated. It is found both transparent and opaque nanoparticles embedding are with high densities and good uniformities.
An Intelligent Systems Approach For An Ultrasonic Based Neuro-Navigation System, Jennifer Akers, Sanjeevi Chitikeshi, Ajay Mahajan, Tsuchin Chu, Etienne Witte, Sumeer Lal
An Intelligent Systems Approach For An Ultrasonic Based Neuro-Navigation System, Jennifer Akers, Sanjeevi Chitikeshi, Ajay Mahajan, Tsuchin Chu, Etienne Witte, Sumeer Lal
Dr. Ajay Mahajan
This paper shows the feasibility of using an intelligent systems approach to increase the accuracy of a 3D ultrasonic position estimation system for real-time image guided neurosurgery. Current image guided systems use camera based technology that is space-intensive, have an accuracy of about 1.0–2.0 mm, and are prone to occasional failures. The 3D system presented in this paper eliminates the space intensive camera, has an accuracy of around 1.0 mm in the operating range of about 200–400 mm, makes the system independent of line-of-sight occlusion problems, and is expected to pave the way for accurate fusion models of MRI and …
Monte Carlo Simulation Of Tri-Functional Branching And Tetra-Functional Crosslinking In Emulsion Polymerization Of Butadiene, Esmaiel Jabbari
Monte Carlo Simulation Of Tri-Functional Branching And Tetra-Functional Crosslinking In Emulsion Polymerization Of Butadiene, Esmaiel Jabbari
Esmaiel Jabbari
No abstract provided.
Using Thermally Coupled Reactive Distillation Columns In Biodiesel Production, Nghi Nguyen, Yaşar Demirel
Using Thermally Coupled Reactive Distillation Columns In Biodiesel Production, Nghi Nguyen, Yaşar Demirel
YASAR DEMIREL
Production of ethyl dodecanoate (biodiesel) using lauric acid and methanol with a solid acid catalyst of sulfated zirconia is studied by using two distillation sequences. In the first sequence, the methanol recovery column follows the reactive distillation column. In the second sequence, the reactive distillation and methanol recovery columns are thermally coupled. Thermally coupled distillation sequences may consume less energy by allowing interconnecting vapor and liquid streams between the two columns to elminate reboiler or condenser or both. Here we study the thermally coupled side-stripper reactive distillation and eliminate the condenser of the reactive distillation column. Both the sequences are …
Viscoplastic Cap Model For Soils Under High Strain Rate Loading, Xiaoli Tong, Christopher Tuan
Viscoplastic Cap Model For Soils Under High Strain Rate Loading, Xiaoli Tong, Christopher Tuan
Christopher Y. Tuan
A viscoplastic cap model of the Perzyna type was developed for simulating high strain rate behaviors of soils. An associative viscous flow rule was used to represent time-dependent soil behaviors. The viscoplastic cap model was validated against experimental data from static and dynamic soil tests. The model was also compared with soil behaviors under creep and stress relaxation with good agreement. However, the model was unable to represent tertiary creep where strain softening became significant. The model was subsequently integrated into LS-DYNA for finite-element simulations of high strain rate behaviors of sandy and clayey soils in explosive tests. The significance …
Development Of Kansas Guardrail To Bridgerail Transition Designs Using Barrier Vii, Christopher Tuan, Edward Post, Syed Atuallah, J. Brewer
Development Of Kansas Guardrail To Bridgerail Transition Designs Using Barrier Vii, Christopher Tuan, Edward Post, Syed Atuallah, J. Brewer
Christopher Y. Tuan
BARRIER VII computer code was used to evaluate the dynamic performance of five Kansas guardrail-to-bridgerail transition designs. The simulation results were compared with those of two FHWA-approved transition designs. The test vehicle model was a 4,500-lb, 1977 Plymouth impacting the barriers at 60 mph with an approach angle of 25 deg. The vehicle-crushing properties and guardrail-post stiffness had been validated using full-scale vehicle crash test data before the simulations were conducted. A methodology for wheel-snagging prediction was also proposed and validated against available test data. It was shown that reliable simulation results could be obtained if the input parameters for …
Foot And Ankle Forces During An Automobile Collision: The Influence Of Muscles, Elizabeth Hardin, Anne Su, Antonie Van Den Bogert
Foot And Ankle Forces During An Automobile Collision: The Influence Of Muscles, Elizabeth Hardin, Anne Su, Antonie Van Den Bogert
Anne Su Ph.D.
Muscles have a potentially important effect on lower extremity injuries during an automobile collision. Computational modeling can be a powerful tool to predict these effects and develop protective interventions. Our purpose was to determine how muscles influence peak foot and ankle forces during an automobile collision. A 2-D bilateral musculoskeletal model was constructed with seven segments. Six muscle groups were included in the right lower extremity, each represented by a Hill muscle model. Vehicle deceleration data were applied as input and the resulting movements were simulated. Three models were evaluated: no muscles (NM), minimal muscle activation at a brake pedal …
Progressive Failure Simulation Of Security Cable Barriers, Christopher Tuan, Ratul Sarmah, Alexander Tuan, Ching-Sheng Kao, Q. Li
Progressive Failure Simulation Of Security Cable Barriers, Christopher Tuan, Ratul Sarmah, Alexander Tuan, Ching-Sheng Kao, Q. Li
Christopher Y. Tuan
Perimeter security cable barriers are widely used by various agencies all over the world to defeat threat vehicle penetration. New barrier designs require crash test validation prior to implementation. Full-scale vehicular crash tests are costly, whereas designs via finite element simulations are time consuming and require specialized skills. Based on full-scale crash tests, an innovative and simple algorithm has been developed to model the progressive failure of security cable barriers. A multi-body approach based on the first principles of physics was developed to substantially reduce computer runtime. The solution algorithm uses a large number of small time steps. Nonlinear vehicle …
Energy Modeling Of Wireless Sensor Nodes Based On Petri Nets, Ali Shareef, Yifeng Zhu
Energy Modeling Of Wireless Sensor Nodes Based On Petri Nets, Ali Shareef, Yifeng Zhu
Yifeng Zhu
Energy minimization is of great importance in wireless sensor networks in extending the battery lifetime. Accurately understanding the energy consumption characteristics of each sensor node is a critical step for the design of energy saving strategies. This paper develops a detailed probabilistic model based on Petri nets to evaluate the energy consumption of a wireless sensor node. The model factors critical components of a sensor node, including processors with emerging energy-saving features, wireless communication components, and an open or closed workload generator. Experimental results show that this model is more flexible and accurate than Markov models. The model provides a …
Introduction To The Geant4 Simulation Toolkit, Susanna Guatelli, D Cutajar, Bradley Oborn, Anatoly Rosenfeld
Introduction To The Geant4 Simulation Toolkit, Susanna Guatelli, D Cutajar, Bradley Oborn, Anatoly Rosenfeld
Dean Cutajar
Geant4 is a Monte Carlo simulation Toolkit, describing the interactions of particles with matter. Geant4 is widely used in radiation physics research, from High Energy Physics, to medical physics and space science, thanks to its sophisticated physics component, coupled with advanced functionality in geometry description. Geant4 is widely used at the Centre for Medical Radiation Physics (CMRP), at the University of Wollongong, to characterise and optimise novel detector concepts, radiotherapy treatments, and imaging solutions. This lecture consists of an introduction to Monte Carlo method, and to Geant4. Particular attention will be devoted to the Geant4 physics component, and to the …
Transferring Advanced Physics Research Tools To Education: How To Teach Simulation Tools Used In Radiation Physics Research To University Students, Susanna Guatelli, Catherine Layton, Dean Cutajar, Anatoly Rosenfeld
Transferring Advanced Physics Research Tools To Education: How To Teach Simulation Tools Used In Radiation Physics Research To University Students, Susanna Guatelli, Catherine Layton, Dean Cutajar, Anatoly Rosenfeld
Dean Cutajar
At the Centre of Medical Radiation Physics (CMRP), School of Engineering Physics, Faculty of Engineering, at the University of Wollongong (UOW), we are implementing a hands-on computing laboratory, commencing in autumn 2010, to teach scientific computing methods and modern, advanced research tools for radiation physics to postgraduate and undergraduate students. Engaging undergraduates and postgraduates together in work with a tool widely used in research laboratories is a unique development, and represents the articulation of the University’s commitment to the enhancement of the teaching/research nexus, and to the development of learning communities. The object of the laboratory is to teach students …
Evaluating The Impact Of Patient Arrival Patterns In The Performance Of Appointment Scheduling Rules, Alcides Santander-Mercado, Jose Zayas-Castro, Laila Cure, Ali Yalcin
Evaluating The Impact Of Patient Arrival Patterns In The Performance Of Appointment Scheduling Rules, Alcides Santander-Mercado, Jose Zayas-Castro, Laila Cure, Ali Yalcin
Laila Cure
This paper evaluates the ability of commonly used Appointment Scheduling Rules (ASRs) in smoothing the effect of environmental factors in the performance of an outpatient scheduling system. ASRs have been widely implemented in outpatient clinics to improve performance measures such as staff idle time, patient waiting time, and facility congestion. However, the successful implementation of an ASR depends on its ability in dealing with the environmental factors affecting the system. Factors such as no-shows, variability of consultation times, patient unpunctuality, walk-in patient arrivals and the number of admitted patients per session affect the performance of the clinics in terms of …