Engineering Commons^™

Predicting The Performance Of Queues: A Data Analytic Approach, Kum Khiong Yang, Cayirli Tugba, Mei Wan Low

Research Collection Lee Kong Chian School Of Business

Existing models of multi-server queues with system transience and non-standard assumptions are either too complex or restricted in their assumptions to be used broadly in practice. This paper proposes using data analytics, combining computer simulation to generate the data and an advanced non-linear regression technique called the Alternating Conditional Expectation (ACE) to construct a set of easy-to-use equations to predict the performance of queues with a scheduled start and end time. Our results show that the equations can accurately predict the queue performance as a function of the number of servers, mean arrival load, session length and service time variability. …

Exploratory Assessment Of Roadway Infrastructure Adaptation To The Impacts Of Sea-Level Rise, Mostafa Batouli

FIU Electronic Theses and Dissertations

Transportation agencies in coastal urban areas face a significant challenge to enhance the long-term resilience of their networks to flooding and storm surge events exacerbated by sea level rise. The problem of sea-level rise adaptation is characterized by deep uncertainty that makes it complex to assess the value of adaptation investments. To enable informed adaptation decisions, the present study created a dynamic stochastic modeling framework based on the theoretical underpinnings of complex adaptive systems that integrates: (i) stochastic simulation of sea-level rise stressors based on the data obtained from downscaled climate studies pertaining to future projections of sea-level and precipitation; …

Optimizing The Telescope Assembly Alignment Simulator For Sofia, Zoe E. Sharp, Alex Quyenvo, Jennifer Briggs, Brian Eney

STAR Program Research Presentations

The Stratospheric Observatory for Infrared Astronomy (SOFIA) conducts research on a modified Boeing 747sp aircraft. By using a variety of infrared science instruments mounted on a 2.7 meter telescope, researchers can make discoveries about the galactic center, star formation, and various topics associated with a deeper understanding of our universe. To efficiently collect data through the SOFIA instruments, the instruments must be tested and prepared prior to being placed on the aircraft. Therefore, with the use of the Telescope Assembly Alignment Simulator (TAAS), researchers can design and construct improvements needed for these instruments to efficiently perform while in flight. The …

Optimal Disposition Decisions For A Remanufacturing System Considering Time Value Of Products, Mostafa Pazoki, Walid Abdul-Kader

Industrial and Manufacturing Systems Engineering Publications

This paper studies disposition decisions of cores where the value of returns deteriorates over time. Mainly in disposition decisions, a remanufacturer is interested to determine how many units to remanufacture and to salvage. To address this research problem along with value deterioration of returns, a rough-cut mathematical model is developed by considering various parameters of interest such as selling price, salvage value and remanufacturing rate with the aim to maximize total profit. Due to uncertainty limitations, the model can provide decision-makers with relevant insights about disposition decisions. Simulation modeling techniques are used to validate the proposed model. Numerical examples are …

A System-Of-Systems Framework For Assessment Of Resilience In Complex Construction Projects, Jin Zhu

FIU Electronic Theses and Dissertations

Uncertainty is a major reason of low efficiency in construction projects. Traditional approaches in dealing with uncertainty in projects focus on risk identification, mitigation, and transfer. These risk-based approaches may protect projects from identified risks. However, they cannot ensure the success of projects in environments with deep uncertainty. Hence, there is a need for a paradigm shift from risk-based to resilience-based approaches. A resilience-based approach focuses on enhancing project resilience as a capability to cope with known and unknown uncertainty. The objective of this research is to fill the knowledge gap and create the theory of resilience in the context …

Fractional Transport Models For Shale Gas In Tight Porous Media, Nadeem A. Malik, Iftikhar Ali

Sixth International Conference on Porous Media and Its Applications in Science, Engineering and Industry

Modelling the flow of fluid through tight porous media, such as unconventional hydrocarbon reservoirs, is very challenging and it is a growing sector and must be addressed. Shale gas is found in such tight porous rocks which are characterized by nano-scale size porous networks with ultra-low permeability [1,2].

Please download the full abstract below.

Flow Of Shale Gas In Tight Rocks Using A Non-Linear Transport Model With Pressure Dependent Model Parameters, Nadeem A. Malik, Iftikhar Ali, Bilal Chanane, Ryad A. Ghanam

Sixth International Conference on Porous Media and Its Applications in Science, Engineering and Industry

A new source of energy has recently been discovered from unconventional hydrocarbon reservoirs, such as shale gas deposits. Shale gas is found in tight porous rocks which are characterised by nano-scale size porous networks with ultra-low permeability [1,2]. The modelling of transport through such tight porous media is very challenging because it is a relatively new discipline and not much is known but transport processes in them, and little data is available; but it is a growing sector and must be addressed. Here, we apply a recently developed non-linear gas transport model [3], to reservoir simulations of single-phase gas through …

Bunch Splitting Simulations For The Jleic Ion Collider Ring, R. Gamage, T. Satogata

Physics Faculty Publications

We describe the bunch splitting strategies for the proposed JLEIC ion collider ring at Jefferson Lab. This complex requires an unprecedented 9:6832 bunch splitting, performed in several stages. We outline the problem and current results, optimized with ESME including general parameterization of 1:2 bunch splitting for JLEIC parameters.

Development Of A Transition Between An Energy-Absorbing Concrete Barrier And A Rigid Concrete Buttress, Tyler Schmidt

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

From 2010 to 2015, MwRSF researchers developed the RESTORE barrier, which is a restorable MASH TL-4 median barrier with a steel and concrete rail supported by elastomer posts and steel skids. The research effort reported herein describes the initial development of a transition from the RESTORE barrier to a rigid TL-4 concrete buttress.

The previously-developed RESTORE barrier LS-DYNA model was validated against three full-scale vehicle crash tests. Several design concepts were generated through a series of brainstorming efforts. The primary transition concept consisted of a pin and loop connection between the RESTORE barrier and rigid concrete buttress, which was designed …

Advances In Repurposing And Recycling Of Post-Vehicle-Application Lithium-Ion Batteries, Charles R. Standridge, Lindsay Corneal, Nicholas Baine

Mineta Transportation Institute

Increased electrification of vehicles has increased the use of lithium-ion batteries for energy storage, and raised the issue of what to do with post-vehicle-application batteries. Three possibilities have been identified: 1) remanufacturing for intended reuse in vehicles; 2) repurposing for non-vehicle, stationary storage applications; and 3) recycling, extracting the precious metals, chemicals and other byproducts. Advances in repurposing and recycling are presented, along with a mathematical model that forecasts the manufacturing capacity needed for remanufacturing, repurposing, and recycling. Results obtained by simulating the model show that up to a 25% reduction in the need for new batteries can be achieved …

Modelling And Fem Simulation Of Electric Field Assisted Sintering Of Tungsten Carbide (Wc), Sree Koundinya

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Numerical modeling of sintering and its process variants (such as Hot Pressing, Hot Isostatic Pressing (HIP), Field Assisted Sintering Technique (FAST) or Spark Plasma Sintering (SPS), etc.) has been a field of interest among researchers and industrialists due to its efficiency in predicting various sintering characteristics such as densification, volumetric and shape changes. Thus, various mathematical models have been developed over the years, where, earlier models for sintering included rheological investigations which were able to capture the macroscopic shape and volume changes of a porous body over the process of sintering and were known as phenomenological models [1]. Due to …

Zion File System Simulator, Robert Adams, Frederic Paladin

Funded Articles

File systems are fundamental for computers and devices with data storage units. They allow operating systems to understand and organize streams of bytes and obtain readable files from them. There are numerous file systems available in the industry, all with their own unique features. Understanding how these file systems work is essential for computer science students, but their complex nature can be difficult and challenging to grasp, especially for students at the beginning of their career. The Zion File System Simulator was designed with this in mind. Zion is a teaching and experimenting tool, in the form of a small …

Cepsim: Modelling And Simulation Of Complex Event Processing Systems In Cloud Environments, Wilson A. Higashino, Miriam Am Capretz, Luiz F. Bittencourt

Electrical and Computer Engineering Publications

The emergence of Big Data has had profound impacts on how data are stored and processed. As technologies created to process continuous streams of data with low latency, Complex Event Processing (CEP) and Stream Processing (SP) have often been related to the Big Data velocity dimension and used in this context. Many modern CEP and SP systems leverage cloud environments to provide the low latency and scalability required by Big Data applications, yet validating these systems at the required scale is a research problem per se. Cloud computing simulators have been used as a tool to facilitate reproducible and repeatable …

Team Training In Safety And Security Via Simulation: A Practical Dimension Of Maritime Education And Training, Michael Baldauf, Dimitrios Dalaklis, Aditi Kataria

Conference Papers

In the rather extended maritime domain, a term that should be the epicentre of any successful careerbuilding path is tailor-made training via cutting-edge simulators. To cut a long story short, the breadth of operations on the various types of ships has expanded to such a large extent that extensive practical training drills are becoming a compelling need to contribute to competent seafarers. This type of training can guarantee the positive outcome in their decision-making process and help the seafarers often being under continuous pressure, to suitably respond to the various safety and security threats on-board a vessel. The several conventions …

Simulation-Based Evaluation Of An Integrated Planning And Scheduling Algorithm For Maintenance Projects, Rohit Patil, Nagesh Shukla, Senevi Kiridena

SMART Infrastructure Facility - Papers

The field of maintenance project planning and scheduling is attracting increasing attention due to ever growing competition among manufacturing organisations. There is a lack of studies that has tackled all the aspects of maintenance project implementation such as costs, resources, down times, uncertainties, operational constraints, among others. Therefore, an approach which uses a unitary structuring method and discrete event simulation to integrate relevant data about the maintenance projects is proposed. The results of the evaluation, on a case from paper-pulp industry, have shown that the proposed approach is able to overcome most of the issues of maintenance planning and scheduling.

Effect Of Deformation On Microstructure And Mechanical Properties Of Dual Phase Steel Produced Via Strip Casting Simulation, Zhiping Xiong, Andrii Kostryzhev, Nicole Stanford, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The strip casting is a recently appeared technology with a potential to significantly reduce energy consumption in steel production, compared to hot rolling and cold rolling. However, the quantitative dependences of the steel microstructure and mechanical properties on strip casting parameters are unknown and require investigation. In the present work we studied the effects of strain and interrupted cooling temperature on microstructure and mechanical properties in conventional dual phase steel (0.08C-0.81Si-1.47Mn-0.03Al wt%). The strip casting process was simulated using a Gleeble 3500 thermo-mechanical simulator. The steel microstructures were studied using optical, scanning and transmission electron microscopy. Mechanical properties were measured …

Organ Doses From Hepatic Radioembolization With 90y, 153sm, 166ho And 177lu: A Monte Carlo Simulation Study Using Geant4, N A A Hashikin, C H Y Yeong, Susanna Guatelli, B J J Abdullah, K H. Ng, Alessandra Malaroda, Anatoly B. Rosenfeld, A C. Perkins

Faculty of Engineering and Information Sciences - Papers: Part A

90Y-radioembolization is a palliative treatment for liver cancer. 90Y decays via beta emission, making imaging difficult due to absence of gamma radiation. Since post-procedure imaging is crucial, several theranostic radionuclides have been explored as alternatives. However, exposures to gamma radiation throughout the treatment caused concern for the organs near the liver. Geant4 Monte Carlo simulation using MIRD Pamphlet 5 reference phantom was carried out. A spherical tumour with 4.3cm radius was modelled within the liver. 1.82GBq of 90Y sources were isotropically distributed within the tumour, with no extrahepatic shunting. The simulation was repeated with 153Sm, 166Ho and 177Lu. The estimated …

An Implementation Of Discrete Electron Transport Models For Gold In The Geant4 Simulation Toolkit, D Sakata, Sebastien Incerti, M Bordage, N Lampe, Susumu Okada, Dimitris Emfietzoglou, Ioanna Kyriakou, K Murakami, Takashi Sasaki, H Tran, Susanna Guatelli, V Ivantchenko

Faculty of Engineering and Information Sciences - Papers: Part A

Gold nanoparticle (GNP) boosted radiation therapy can enhance the biological effectiveness of radiation treatments by increasing the quantity of direct and indirect radiation-induced cellular damage. As the physical effects of GNP boosted radiotherapy occur across energy scales that descend down to 10 eV, Monte Carlo simulations require discrete physics models down to these very low energies in order to avoid underestimating the absorbed dose and secondary particle generation. Discrete physics models for electron transportation down to 10 eV have been implemented within the Geant4-DNA low energy extension of Geant4. Such models allow the investigation of GNP effects at the nanoscale. …

A Dielectric Rod Antenna For Picosecond Pulse Stimulation Of Neurological Tissue, Ross A. Petrella, Karl H. Schoenbach, Shu Xiao

Bioelectrics Publications

A dielectrically loaded wideband rod antenna has been studied as a pulse delivery system to subcutaneous tissues. Simulation results applying 100-ps electrical pulse show that it allows us to generate a critical electric field for biological effects, such as brain stimulation, in the range of several centimeters. In order to reach the critical electric field for biological effects, which is similar to 20 kV/cm, at a depth of 2 cm, the input voltage needs to be 175 kV. The electric field spot size in the brain at this position is similar to 1 cm(2). Experimental studies in free space with …

Individual-Level Simulation Model For Cost Benefit Analysis In Healthcare, Nagesh Shukla, Vu Lam Cao, Van Hoang Phuong, Marian D. Shanahan, Alison Ritter, Pascal Perez

SMART Infrastructure Facility - Papers

Illicit drug use creates significant burden at societal, family and personal levels. Every year substantial resources are allocated for treatment and the consequences of illicit drug use in Australia and around the world. Heroin is one of the major forms of illicit drugs. Several independent heroin treatment strategies or interventions exist and state-of-the art research demonstrates their efficacy and relative costeffectiveness. However, assessing total potential gains and burden from providing all treatment interventions or varying the mix of heroin treatments has never been attempted. This paper proposed an individual-level simulation model (ISM) which addresses net social benefit over a lifetime …

Microstructure And Mechanical Properties Of Strip Cast Trip Steel Subjected To Thermo-Mechanical Simulation, Zhiping Xiong, Andrii Kostryzhev, Liang Chen, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

Instead of hot rolling and cold rolling followed by annealing, strip casting is a more economic and environmentally friendly way to produce transformation-induced plasticity (TRIP) steels. According to industrial practice of strip casting, rapid cooling in this work was achieved using a dip tester, and a Gleeble 3500 thermo-mechanical simulator was used to carry out the processing route. A typical microstructure of TRIP steels, which included ~0.55 fraction of polygonal ferrite with bainite, retained austenite and martensite, was obtained. The effects of deformation (0.41 reduction) above non-recrystallisation temperature, isothermal bainite transformation temperature and the size of second phase region on …

Particle Size Segregation Of Bulk Material In Dustiness Testers Via Dem Simulation, Sathaphon Wangchai, David B. Hastie, Peter W. Wypych

Faculty of Engineering and Information Sciences - Papers: Part A

Dustiness testers are used to quantify the level of dust within a bulk material. The generation of dust can occur as a result of many bulk material handling activities, including filling or discharge from storage bins, during free-fall, material impact on conveyor transfers, or impact with other materials. Dust generation can have a serious impact to the environment as well as workers and nearby communities. This paper presents the findings of a discrete element modeling (DEM) study of the flow behavior of a range of binary granular mixes tested in the European Standard and the Australian Standard dustiness testers. Due …

Coupling A Thermal Comfort Model With Building Simulation For User Comfort And Energy Efficiency, Katharina Boudier, Massimo Fiorentini, Sabine Hoffmann, Raghuram Kalyanam, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part B

This paper describes a methodology for coupling an advanced model of the thermo-regulatory system of the human body that describes its physiological processes, a comfort model that evaluates thermal sensation and comfort, and the ESP-r building simulation software that computes the transient thermal response of a building model. The objective of this study was to utilise the physiology and comfort models to dynamically modify the heating and cooling temperature set points of a zone controller in ESP-r, in accordance with the computed human thermal sensation and achieve realtime thermal comfort management. The comunication between the software is managed by the …

A Recommendation System For Meta-Modeling: A Meta-Learning Based Approach, Can Cui, Mengqi Hu, Jeffery D. Weir, Teresa Wu

Faculty Publications

Various meta-modeling techniques have been developed to replace computationally expensive simulation models. The performance of these meta-modeling techniques on different models is varied which makes existing model selection/recommendation approaches (e.g., trial-and-error, ensemble) problematic. To address these research gaps, we propose a general meta-modeling recommendation system using meta-learning which can automate the meta-modeling recommendation process by intelligently adapting the learning bias to problem characterizations. The proposed intelligent recommendation system includes four modules: (1) problem module, (2) meta-feature module which includes a comprehensive set of meta-features to characterize the geometrical properties of problems, (3) meta-learner module which compares the performance of instance-based …