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Multi-Period Liner Ship Fleet Planning With Dependent Uncertain Container Shipment Demand, Qiang Meng, Tingsong Wang, Shuaian Wang 2015 University of Wollongong

Multi-Period Liner Ship Fleet Planning With Dependent Uncertain Container Shipment Demand, Qiang Meng, Tingsong Wang, Shuaian Wang

Faculty of Engineering and Information Sciences - Papers

This paper deals with a realistic multi-period liner ship fleet planning problem by incorporating stochastic dependency of the random and period-dependent container shipment demand. This problem is formulated as a multi-period stochastic programming model with a sequence of interrelated two-stage stochastic programming (2SSP) problems characterized ship fleet planning in each single period. A solution method integrating dual decomposition and Lagrangian relaxation method is designed for solving the developed model. Numerical experiments are carried out to assess applicability and performance of the proposed model and solution algorithm. The results further demonstrate importance of stochastic dependence of the uncertain container shipment demand.


Nyiso – Selected Topics, Dejan Sobajic 2014 Engineering Conferences International

Nyiso – Selected Topics, Dejan Sobajic

Modeling, Simulation, And Optimization for the 21st Century Electric Power Grid

No abstract provided.


Injectable, Magnetic Plum Pudding Hydrogel Composites For Controlled Pulsatile Drug Release, Danielle Maitland 2014 McMaster University

Injectable, Magnetic Plum Pudding Hydrogel Composites For Controlled Pulsatile Drug Release, Danielle Maitland

Open Access Dissertations and Theses

Injectable, in-situ gelling magnetic plum pudding hydrogel composites were fabricated by entrapping superparamagnetic iron oxide nanoparticles (SPIONs) and thermosensitive N-isopropylacrylamide (NIPAM)-co–N-isopropylmethacrylamide (NIPMAM) microgels in a pNIPAM-hydrazide/carbohydrate-aldehyde hydrogel matrix. The resulting composites exhibited significant, repeatable pulsatile release of 4 kDa FITC-dextran upon exposure to an alternating magnetic field. The pulsatile release from the composites could be controlled by altering the volume phase transition temperatures of the microgel particles (with VPTTs over 37°C corresponding to improved pulsatile release) and changing the microgel content of the composite (with higher microgel content corresponding to higher pulsatile release). By changing the ...


Measurement And Prediction Of The Onset Of Intermittent Dryout During Blowdown Transients For Upward Annular Flow, Bradley A. Statham 2014 McMaster University

Measurement And Prediction Of The Onset Of Intermittent Dryout During Blowdown Transients For Upward Annular Flow, Bradley A. Statham

Open Access Dissertations and Theses

The effect of pressure transients on the onset of intermittent dryout in upward annular flow was experimentally investigated in order to resolve the conflict between the observations drawn from two major data sets in the literature. A delay in time to the onset of dryout at the test section exit relative to the time predicted based on steady-state data was observed in the R-12 experiments of Celata et al (1988; 1991). Steady-state prediction methods were sufficient to predict the upstream progression of a pre-existing dryout front in the water experiments of Lyons and Swinnerton (1983). Steady state and pressure transient ...


A Multi-Well Concentration Gradient Drug Delivery Microfluidic Device For High-Content And High-Throughput Screening, Michael M. Nelson 2014 McMaster University

A Multi-Well Concentration Gradient Drug Delivery Microfluidic Device For High-Content And High-Throughput Screening, Michael M. Nelson

Open Access Dissertations and Theses

A microfluidic device capable of drug delivery to multiple wells in a concentration gradient was designed for automated high content and high throughput screening. The design was proposed to utilize a nanoporous polycarbonate membrane to spatially and temporally control drug dosage from the microchannels below to the wells above. Microchannels were to hold to the drugs or reagents, while wells were to culture cells. An array of 16 wells was to fit in the equivalent area of a single well of a 96 well plate. Two simpler devices were created to validate electrokinetic drug delivery to a single well and ...


Explicit Solution Of The Large Amplitude Transverse Vibrations Of A Flexible String Under Constant Tension, Ali Nikkar, Reza Taghipour, Tohid Akhlaghi 2014 SelectedWorks

Explicit Solution Of The Large Amplitude Transverse Vibrations Of A Flexible String Under Constant Tension, Ali Nikkar, Reza Taghipour, Tohid Akhlaghi

Ali Nikkar

This paper presents the analytical simulation of string with large amplitudes using the Variational Iteration Method (VIM) and Hamiltonian Approach (HA). In order to verify the precision of the presented methods, current results were compared with He’s Variational Approach and Runge-Kutta 4th order. It has been found that these methods are well suited for a range of parameters and the approximate frequencies and periodic solutions show a good agreement with other techniques. The results show that both methods can be easily extended to other nonlinear oscillations and it can be predicted that both methods can be found widely applicable ...


Structural And Catalytic Differences In The Effect Of Co And Mo As Promoters For Pt-Based Aqueous Phase Reforming Catalysts, Paul J. Dietrich, Fred G. Sollberger, M. Cem Akatay, Eric A. Stach, W.Nicholas Delgass, Jeffrey T. Miller, Fabio H. Ribeiro 2014 Purdue University

Structural And Catalytic Differences In The Effect Of Co And Mo As Promoters For Pt-Based Aqueous Phase Reforming Catalysts, Paul J. Dietrich, Fred G. Sollberger, M. Cem Akatay, Eric A. Stach, W.Nicholas Delgass, Jeffrey T. Miller, Fabio H. Ribeiro

Birck and NCN Publications

Reaction rates (site time yields, normalized to CO chemisorption sites) and product selectivity were determined for PtCo, PtMo, and Pt supported on multi-walled carbon nanotubes for aqueous phase reforming of glycerol. The bimetallic PtCo and PtMo catalysts had 4.6x and 5.4x higher glycerol consumption rates than Pt, and 3.9x and 0.6x rates in H-2 formation compared to Pt. Hydrogen generation selectivity was similar on Pt and PtCo, but PtMo had an increase in selectivity to C-O cleavage products, which reduced H-2 yield at conversions over 60% (85-90% hydrogen yield for Pt and PtCo, 65% for PtMo ...


Failures Of Mainline Railway Sleepers And Suggested Remedies-Review Of Current Practice, Wahid Ferdous 2014 SelectedWorks

Failures Of Mainline Railway Sleepers And Suggested Remedies-Review Of Current Practice, Wahid Ferdous

Wahid Ferdous

Over the last two decades, the premature failures of traditional railway sleepers have significantly increased the track maintenance costs. The primary obstacle to minimising this problem is the lack of understanding of the mechanism of sleeper degradation. This paper discusses the different deterioration mechanisms for traditional timber, concrete and steel sleepers and the potential protective measures to minimise these problems. This paper exhaustively reviews the failure mechanisms of these three commonly used sleeper materials with suggested solutions. Fungal decay, end splitting and termite attacks has been identified as the principal causes of timber sleeper failures. On the other hand, concrete ...


Implementation And Validation Of Aortic Remodeling In Hypertensive Rats, Shijia Zhao, Linxia Gu 2014 University of Nebraska - Lincoln

Implementation And Validation Of Aortic Remodeling In Hypertensive Rats, Shijia Zhao, Linxia Gu

Mechanical & Materials Engineering Faculty Publications

A computational framework was implemented and validated to better understand the hypertensive artery remodeling in both geometric dimensions and material properties. Integrating the stress-modulated remodeling equations into commercial finite element codes allows a better control and visualization of local mechanical parameters. Both arterial thickening and stiffening effects were captured and visualized. An adaptive material remodeling strategy combined with the element birth and death techniques for the geometrical growth were implemented. The numerically predicted remodeling results in terms of the wall thickness, inner diameter, and the ratio of elastin to collagen content of the artery were compared with and fine-tuned by ...


Assessment Of Policies For Innovative Financing In Infrastructure Systems, Ali Mostafavi, Dulcy Abraham, Charlene Sullivan 2014 Florida International University

Assessment Of Policies For Innovative Financing In Infrastructure Systems, Ali Mostafavi, Dulcy Abraham, Charlene Sullivan

Infrastructure System-of-Systems (I-SoS ) Research Group

Infrastructure systems are drivers of the economy in the nation. A dollar spent on infrastructure development yields roughly double the initial spending in ultimate economic output in the short term; and over a twenty-year period, and generalized ‘public investment’ produces an aggregated $3.21 of economic activity per $1.00 spent [1]. Thus, formulation of policies pertaining to infrastructure investment and development is of significance affecting the social and economic wellbeing of the nation. The aim of this policy brief is to evaluate innovative financing in infrastructure systems from two different perspectives: (1) through consideration of the current condition of ...


Turbulent Circular Culvert Flow: Implications To Fish Passage Design, Amin Mohebbi 2014 University of Nebraska - Lincoln

Turbulent Circular Culvert Flow: Implications To Fish Passage Design, Amin Mohebbi

Civil Engineering Theses, Dissertations, and Student Research

Culverts are popular conveyance structures in America and Canada to be used as a fish passage or in sewage collection and disposal systems. Fish passage design criteria is based on biological capabilities of fish whereas it should satisfy hydraulic and hydrological constraints as well. Failing to provide enough low velocity regions for aquatic organisms may result in their mass extinctions. Currently, proper road crossing design depends on either model studies or numerical simulations via Computational Fluid Dynamic (CFD) packages, both of which are expensive and time consuming. Further, although the design procedures released by FHWA recently ensures safe fish migration ...


Exploration Of The Validity Of The Two-Dimensional Sagittal Plane Standing Long Jump Model, Lauren Hickox 2014 Grand Valley State University

Exploration Of The Validity Of The Two-Dimensional Sagittal Plane Standing Long Jump Model, Lauren Hickox

Masters Theses

Most previous standing long jump studies have been based on the assumption of two-dimensional sagittal plane motion. The purpose of this study was to investigate the validity of this assumption. Standing long jump trials were collected using six adult male subjects. Each subject stood with a foot on each of two force plates and performed eight standing long jumps for maximal distance. Inverse dynamics analyses were performed for the two-dimensional (2D) and three-dimensional (3D) models and the joint moments, powers, and work values were compared. The differences between these models with respect to the validity of the common planar jumping ...


Feeding Condensed Distillers Solubles To Feedlot Finishing Steers And The Effects Of Feed Additives In Adaptation Diets, Marie E. Harris 2014 University of Nebraska - Lincoln

Feeding Condensed Distillers Solubles To Feedlot Finishing Steers And The Effects Of Feed Additives In Adaptation Diets, Marie E. Harris

Theses and Dissertations in Animal Science

By-products from the dry-milling ethanol process can be used in cattle diets to replace corn. There is a significant interaction between corn processing methods as CCDS concentration increases in the diet. Improvements are observed for SFC in final BW, ADG, and G:F over DRC. An experiment was conducted to determine if greater concentrations of CCDS could be fed in SFC based diets and maintain or improve performance. Performance and carcass characteristics were evaluated with increasing concentrations of CCDS at 0, 9, 18, 27, or 36% in place of SFC in feedlot finishing diets. As CCDS concentration increased, DMI decreased ...


Shape Optimization Of Airfoils Without And With Ground Effect Using A Multi-Objective Genetic Algorithm, Yilei He 2014 Washington University in St. Louis

Shape Optimization Of Airfoils Without And With Ground Effect Using A Multi-Objective Genetic Algorithm, Yilei He

Engineering and Applied Science Theses & Dissertations

The focus of this thesis is on shape optimization using a genetic algorithm. A multi-objective genetic algorithm (MOGA) is employed to optimize the shape of an airfoil to improve its lift and drag characteristics, in particular to achieve two objectives simultaneously that is to increase its lift as well as its lift to drag ratio. The commercially available software FLUENT is employed to calculate the flow field on an adaptive structured mesh, which is generated by the commercial mesh generating software ICEM. The flow field is calculated using the Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with a two equation k-ω ...


Review Of Microbially Induced Corrosion And Comments On Needs Related To Testing Procedures, Mitchell House, W. J. Weiss 2014 Purdue University

Review Of Microbially Induced Corrosion And Comments On Needs Related To Testing Procedures, Mitchell House, W. J. Weiss

International Conference on Durability of Concrete Structures

Concrete is the most widely used material for the construction of the wastewater collection, storage, and treatment infrastructure. The chemical and physical characteristics of hydrated Portland cement may make it susceptible to degradation under highly acidic conditions. As a result, some concrete wastewater infrastructure may be susceptible to a multistage degradation process known as microbially induced corrosion (MIC). MIC begins with the production of aqueous hydrogen sulfide (H2S(aq)) by anaerobic sulfate-reducing bacteria present below the waterline. H2S(aq) partitions to the gas phase where it is oxidized to sulfuric acid by the aerobic sulfur-oxidizing bacteria Thiobacillus that resides on ...


Numerical Simulation Method For Fracture Effect Of Corroded Steel Strand Under Tension, Fumin Li, Yaxu Qu, Yu Zhao, Rong Lu 2014 Purdue University

Numerical Simulation Method For Fracture Effect Of Corroded Steel Strand Under Tension, Fumin Li, Yaxu Qu, Yu Zhao, Rong Lu

International Conference on Durability of Concrete Structures

Steel strand presents characteristic pitting corrosion in chloride environment, which leads PC structures to a serious structural failure even with light presentational corrosion. So it is necessary to analyze the fracture effect of steel strand caused by pitting corrosion. The theoretical analyses are difficult for the presence of complicated threedimension pits, so numerical method becomes a feasible choice. A numerical simulation method for fracture effect of corroded steel strand under tension by the ANSYS software is introduced in this paper, which contains mainly four issues such as fracture criterion, constitutive relation, geometrical models, and simplified mechanical models. The Mises strain ...


Effects Of Stirrups On Bond Behavior Between Concrete And Corroded Steel Bars, Hongwei Lin, Yuxi Zhao, Ming Sun 2014 Purdue University

Effects Of Stirrups On Bond Behavior Between Concrete And Corroded Steel Bars, Hongwei Lin, Yuxi Zhao, Ming Sun

International Conference on Durability of Concrete Structures

Steel corrosion leads to the deterioration of bond between concrete and steel bars. The serviceability and ultimate strength of concrete elements within RC structures are hence affected. Many researchers have studied the bond behavior of corroded steel bars. However, very few studies have investigated the effects of confinements on the degradation of bond strength. The present paper proposed a new kind of beam specimen based on which the effects of stirrups on degradation of bond were investigated. The test results proved that stirrups can effectively increase the bond strength between concrete and corroded steel bars.


Behavior Of Steel–Concrete Composite Beams With Corroded Shear Studs Under Negative Bending Moment, Ju Chen, A. Jiang, W. Jin 2014 Purdue University

Behavior Of Steel–Concrete Composite Beams With Corroded Shear Studs Under Negative Bending Moment, Ju Chen, A. Jiang, W. Jin

International Conference on Durability of Concrete Structures

The behavior of corroded steel–concrete composite beams under hogging moment was studied by experimental investigation and theoretical analysis. A total of eight specimens, six of which had corroded shear studs, were tested. The corrosion rate of studs ranged from 0 to approximately 50%. The constant-current accelerated corrosion method was adopted to accelerate the corrosion process. The loading test results indicated that the bending capacity of the corroded beams decreased slightly with increasing corrosion ratio of the studs. The corroded beams also exhibited an obvious decrease in bending rigid stiffness and increase in the slip between the steel beam and ...


Prediction Of Corrosion-Induced Crack Width Of Corroded Reinforced Concrete Structures, Jin Xia, Wei-Liang Jin 2014 Purdue University

Prediction Of Corrosion-Induced Crack Width Of Corroded Reinforced Concrete Structures, Jin Xia, Wei-Liang Jin

International Conference on Durability of Concrete Structures

This paper presents an experimental investigation on the crack width induced by the corrosion of reinforcing steel bars in concrete. Reinforcing steel bars with different diameters were corroded using an accelerated test in three types of concrete members, including 24 beams with corroded stirrup and 20 beams with corroded longitudinal reinforcing steel bars. The corrosion patterns and rusts characteristics of the corroded steel bars were examined and compared with those observed in real RC structures. According to the experimental result, the corrosioninduced crack width were analyzed and showed a linear relationship with the corrosion loss of reinforcing steel bar. Finally ...


Flexural Behavior Of Rc Beams Under Combined Effects Of Acid–Salt Mist And Carbon Dioxide, Wu Yuan-Zhou, Lv Heng-Lin, Fang Zhong-Nian 2014 Purdue University

Flexural Behavior Of Rc Beams Under Combined Effects Of Acid–Salt Mist And Carbon Dioxide, Wu Yuan-Zhou, Lv Heng-Lin, Fang Zhong-Nian

International Conference on Durability of Concrete Structures

The coupling effects of hydrochloric acid mist, carbon dioxide, and salt mist rich in Cl and SO42– on the degradation of reinforcement concrete (RC) beams were researched with the simulation of colliery ground environment (CGE) and experimental investigation. The results indicated that carbonation of concrete and corrosion of rebar increased slowly as the maximum width of crack became <0.5 mm. Meanwhile, the flexural carrying capacity of the deteriorated beam decreased slightly, while the concrete strength got a small increase first and a large decrease of more than 20% quickly. As the width of crack exceeded 0.5 mm, each target changed rapidly except the carbonation depth. Because of the interaction of deteriorated concrete and corroded rebar, the crack width, and flexural behavior of the beams have discrete correlation with the corrosion of rebar. The failure mode of beams changed from the crushing of compression concrete to the yielding of rebar.


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