Engineering Commons^™

Effects Of Warm-Mix Asphalt Additives On Asphalt Mixture Characteristics And Pavement Performance, Jun Zhang

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

The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera synthetic zeolite) were evaluated. For a more realistic evaluation of the WMA approaches, trial pavement sections of the WMA mixtures and their HMA counterparts were implemented in Antelope County, Nebraska. More than one ton of field-mixed loose mixtures were collected at the time of paving and were transported to the NDOR and UNL laboratories to conduct comprehensive laboratory evaluations and pavement performance predictions of the …

A Comprehensive Analysis Of Lte Physical Layer, Fahimeh Rezaei

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

The 3rd Generation Partnership Project (3GPP) introduced Long Term Evolution (LTE) as the 3rd generation of mobile communication standards. LTE Release 8 describes a mobile communication standard which supports up to 300 Mbps of data transmission in downlink using the OFDM scheme as well as up to 75 Mbps throughput for uplink using the SC-FDMA modulation. In this thesis, an in-depth study of LTE performance based on Release 8 is conducted for uplink and downlink under different scenarios. The main objective of this study is to investigate a comprehensive analysis of physical layer throughput of LTE Release8 based on standard …

Fractional Factorial Design Optimization Of Nontraditional Completion Fluid For Perforation With Underbalance, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

Optimal well performance is always associated with the creation of a clean and undamaged connection between wellbore and reservoir. However, it is apparent that the use of shaped-charge perforating tends to produce perforation-induced formation damage. This damage impairs fluid flow and decreases well productivity. To minimize and eliminate this damage, underbalance perforating should be considered. Underbalance perforating has been considered as one of the best means of providing a transient surge flow for tunnel cleanup. This paper introduces the formulation of super lightweight completion to achieve underbalance condition. The formulation was optimized using fractional factorial design. The result indicates that …

High Quality Biodiesel And Its Diesel Engine Application: A Review, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

The continuous increasing demand for energy and the diminishing tendency of petroleum resources has led to the search for alternative renewable and sustainable fuel. Biodiesel is best substitute for petro-diesel and also most advantageous over petro-diesel for its environmental friendliness. The quality of biodiesel fuel was found to be significant for its successful use on compression ignition engines and subsequent replacement of non-renewable fossil fuels. Conventional biodiesel separation and purification technologies were noticed to yield lower quality biodiesel fuel with resultant excessive energy and water consumptions. Membrane technology showed more potential for effective and efficient separation and purification of biodiesel. …

Performance Evaluation Of Open Graded Base Course With Doweled And Non-Doweled Transverse Joints, Robert Schmitt, Samuel Owusu-Ababio, James Crovetti

Transportation Reports with the Wisconsin Department of Transportation

The objectives of this study were to investigate the performance of 20-year old doweled/non-doweled and dense-graded/permeable base test sections on three concrete pavement segments in Wisconsin: USH 18/151 in Iowa and Dane counties, STH 29 in Brown County, and USH 151 in Columbia and Dane Counties. Five pavement bases were placed including: dense graded, asphalt-stabilized permeable, cement-stabilized permeable, and untreated permeable having two gradation sizes.

USH 18/151 test sections had similar performance (PDI) for doweled unsealed pavement on dense and permeable base. Distresses common to all segments included slight to moderate distressed joints/cracks and slight transverse faulting. Asphalt-stabilized permeable base …

Experimental Development Of Compressor And Turbine Performance Maps For Turbomachinery, Michael W. Green

Aerospace Engineering

Turbomachinery performance maps are used to reveal the on and off design performance of compressors and turbines. These maps plot the component’s pressure ratio versus the corrected flow rate for multiple engine rotor speeds. In this experiment, a Boeing T50-BO-8A converted turbojet engine was operated at a wide variety of rotor speeds with orifice plates of different sizes to vary the flow rate. The corrected flow rate through the turbojet ranged from 1.32 to 2.55 lb/s. The pressure ratios for the compressor and turbine ranged from 2.0 to 4.3 and from 1.7 to 4.3, respectively. The resulting performance maps showed …

The Impact Of Flexibility And Capacity Allocation On The Performance Of Primary Care Practices, Liang Wang

Masters Theses 1911 - February 2014

The two important metrics for any primary care practice are: (1) Timely Access and (2) Patient-physician Continuity. Timely access focuses on the ability of a patient to get access to a physician as soon as possible. Patient-physician continuity refers to building a strong or permanent relationship between a patient and a specific physician by maximizing patient visits to that physician. In the past decade, a new paradigm called advanced access or open access has been adopted by practices nationwide to encourage physician to “do today’s work today.” However, most clinics still reserve pre-scheduled appointments for long lead-time appointments due to …

The Influence Of Action Learning On Student Perception And Performance, Brad Stappenbelt

Faculty of Engineering - Papers (Archive)

The study of floating oscillating water column (OWC) wave energy conversion (WEC) device performance includes analysis of the dynamic coupling of the water column and the floating structure. In the present investigation, a mechanical oscillator model was proposed in order to examine this relationship for the heave motion of a floating wave energy conversion device. Characterisation of the dynamic system optimal behaviour was performed by examining the effect of relative OWC and floating structure natural frequencies, the phase relationships of the various system components and the optimal power take-off damping of the system. It was determined that separation of the …

Performance Enhancement Of A Complex Chilled Water System Using A Check Valve: Experimental Validation, Shengwei Wang, Zhenjun Ma, Dian-Ce Gao

Faculty of Engineering - Papers (Archive)

The large primary–secondary chilled water systems often suffer from the excess flow demand and low chilled water temperature difference, which is known as the low ΔT central plant syndrome, during operation. This paper presents an approach for experimental validation of the possible utility of a check valve (i.e., putting a one-direction check valve in the chilled water by-pass line) to solve this operational problem and enhance the overall system performance, prior to a check valve is really installed. The experimental tests were carried out on the complex central chiller plant in a super high-rise building using a simulated check valve …

Temperature Effect On Microstructure And Electromagnetic Performance Of Polycarbosilane And Sugar-Doped Mgb2 Wires, Andrey V. Shcherbakov, Josip Horvat, Olga V. Shcherbakova, Nikolina Novosel, Emil Babic, S. X. Dou

Faculty of Engineering - Papers (Archive)

The effect of processing temperature on structural and superconducting properties of 10 wt.% sugar- and 10 wt.% PCS-doped MgB₂ wires is systematically investigated. It is demonstrated that these dopants significantly enhance the electromagnetic performance of Fe-clad MgB₂ superconductor and increase its potential for practical application. The enhancement of in-field critical current density (J_c(B_a)) and upper critical field (B_c2) is due to formation of a large amount of lattice defects caused by impurities and C substitution into the MgB₂ crystal lattice. High temperature sintering of sugar-doped sample results …

Effect Of Bulk Temperature On The Tribological Performance Of Aqueous Symmetric Tri-Block Copolymers (Ppo-Peo-Ppo And Peo-Ppo-Peo) Based Lubricant, Oyong Novareza, P B. Kosasih, A K. Tieu, Hongtao Zhu

Faculty of Engineering - Papers (Archive)

This work investigates the effect of bulk temperature and the tribological performance of a number of symmetric triblock copolymers on MSI020 commonly in metal forming. It is to determine the best bulk temperature for the lubricants in order to apply in metal fOlming application. The triblock polymers are temperature dependant'. The polymers can be compeletly dissolved in solution since of hydrogen bonding in certain temperature. As temperature increases, the bond is weakend and the polymer break from the water and form dispersion in the water

The Impact Of Strategy And Maturity On Business Analytics And Firm Performance: A Review And Research Agenda, Graeme Shanks, Rajeev Sharma, Peter Seddon, Peter Reynolds

Faculty of Engineering and Information Sciences - Papers: Part A

Business analytics involves interpreting organizational data to improve decision-making and to optimise business processes. It has the potential to improve firm performance and increase competitive advantage. Although many case studies have been reponed that describe business analytics applications and speculate about how they might contribute to firm performance, there is no clearly articulated and theoretically grounded model in the literature. This paper proposes a theoretical framework jor understanding how and why business analytics technology and capabilities can lead to value-creating actions that lead to improved form performance and competitive advantage. We jocus particularly on how strategy and maturity impact business …

Soft Soils Improved By Prefabricated Vertical Drains: Performance And Prediction, Buddhima Indraratna, Cholachat Rujikiatkamjorn, V Wijeyakulasuriya, G Mcintosh, R Kelly

Faculty of Engineering - Papers (Archive)

The use of prefabricated vertical drains with preloading is now common practice and is proving to be one of the most effective ground improvement techniques known. The factors affecting its performance, such as the smear zone, the drain influence zone, and drain unsaturation, are discussed in this paper. In order to evaluate these effects a large scale consolidation test was conducted and it was found that the proposed Cavity Expansion Theory could be used to predict the characteristics of the smear zone based on the soil properties available. Moreover, the procedure for converting an equivalent 2-D plane strain multi-drain analysis …

Performance Of A Prb For The Remediation Of Acidic Groundwater In Acid Sulfate Soil Terrain, Buddhima Indraratna, Gyanendra Regmi, Long Nghiem, A. Golab

Faculty of Engineering - Papers (Archive)

Contaminated groundwater resulting from pyrite oxidation of acid sulfate soils (ASSs) is a major environmental problem in coastal Australia. A column test was carried out for an extended period with recycled concrete to study the efficiency of the reactive materials for neutralizing acidic groundwater. Results show that the actual acid neutralization capacity of the recycled concrete could decrease to less than 50% of the theoretical value due to armoring effects. Nevertheless, the performance is good as a spot treatment in ASS Terrain using a near-zero cost waste product. Based on the test results and site characterization, a permeable reactive barrier …

Seismic Performance-Based Design Of Bridges With Quantitative Local Performance Criteria, M Neaz Sheikh, Frederic Legeron

Faculty of Engineering - Papers (Archive)

Performance based design of bridges for earthquake resistance is still not explicitly used in design. However, most codes specify a level of performance for bridges under various earthquake inputs. In principle, design rules suggested in the code should meet stipulated performance criteria. However, it has been highlighted in the past that design rules are not directly related with stipulated performance criteria. After the presentation of performance criteria and their relation with post-earthquake functional requirements, the article examines the case of the Canadian Bridge Design Code (CAN/CSA-S6-06). Performance of bridges designed with this code is predicted and compared to expected levels. …

Direct Scattered Growth Of Mwnt On Si For High Performance Anode Material In Li-Ion Batteries, Pengfei Gao, Yanna Nuli, Yu-Shi He, Andrew I. Minett, Jiazhao Wang, Jun Yang, Jun Chen

Faculty of Engineering - Papers (Archive)

A novel Si-MWNT nanocomposite synthesized via a CVD process shows a high reversible capacity of over 1500 mAh g⁻¹ and stable cycling performance, which can be ascribed to the maintenance of a good conductive network by means of the direct scattered growth and pinning of MWNTs on Si particles.

Performance Comparison Between An Mrf Damper And An Mre Isolator Incorporated With A Building Structure, Yang Zhou, Weihua Li, Muhammad N. S Hadi

Faculty of Engineering - Papers (Archive)

As an important member of smart materials, magnetorheological elastomers (MREs) exhibit characteristics that their modulus can be controlled by an external magnetic field. Based on these experimental results, a viscoelastic solid model with four parameters was proposed to predict the performance of MRE. A building model, three stories high, was constructed using MATLAB SIMULINK to evaluate the performance of an MRE device in structural control. In addition, the performance of an MRF damper and an MRE device in structural control, where the resultant peak force was selected as a criterion in the evaluation process, was compared and discussed. Two controllers, …

Preparation, Characterization, And Electrochemical Performance Of Li2cusno4 And Li2cusnsio6 Electrodes For Lithium Batteries, Atef Y. Shenouda, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Lithium copper tin silicon oxide was prepared from their precursor compounds using Brij surfactant and different sources of Si such as SiO₂, SiC, and Si₃N₄. A hydrothermal autoclave method was used in the first stage of the preparation. X-ray diffraction characterization revealed that the crystal structures of these compounds were tetragonal. Scanning electron microscope investigation showed that the particle size morphology of Li₂CuSnSiO₆ is larger than that of Li₂CuSnO₄. Electrochemical impedance spectroscopy explained that the cell prepared from the Li₂CuSnSiO₆ electrode using Si_{3 …}

The Comparison Between Nanostructure Control And Other Modifications To Improve The Electrochemical Performance Of Sno, Yong-Mook Kang, Min-Sik Park, Hua-Kun Liu, S. X. Dou

Faculty of Engineering - Papers (Archive)

With an advent of the ubiquitous era, the demand for rechargeable batteries with a higher energy density is getting more and more critical. It is because applications are emerging such as electric vehicles and various types of portable electronic devices. Carbonaceous materials are commonly adopted as the anode material for commercial lithium-ion secondary batteries because it can reversibly intercalate or de-intercalate Li ion. However, low capacity of carbon has become a limiting factor in wider applications, and high capacity alternative to carbonaceous material has thus been sought for. Even if tin and silicon have been considered as one of the …

A Boundary Element Analysis On The Influence Of Krc And E/D On The Performance Of Cyclically Loaded Single Pile In Clay, Sudip Basack

Faculty of Engineering - Papers (Archive)

The environment prevalent in oceans necessitates the piles supporting offshore structures to be designed against lateral cyclic loading initiated by wave action. Such quasi-static load reversal induces deterioration in the strength and stiffness of the soil-pile system, introducing progressive reduction in the bearing capacity associated with increased settlement of the pile foundation. To understand the effect of lateral cyclic load on axial response of single piles in soft clay, a numerical model was previously developed and validated by the author. Using the methodology, further analysis has been carried out to investigate how the variation in relative pilesoil stiffness and eccentricity …

"Organic" Mgb2-Xcx Superconductor With High Performance Enabled By Liquid Mixing Approach, Olga V. Shcherbakova, Alexey V. Pan, Emil Babic, S. X. Dou

Faculty of Engineering - Papers (Archive)

Comparative analysis of structural and electromagnetic characteristics have been performed on nano SiC- and polycarbosilane-doped MgB₂ samples prepared by the dry and liquid mixing approaches. The total benefit of liquid mixing approach for fabrication of "organic" MgB₂ superconductor with excellent electromagnetic performance has been demonstrated

Passive All-Fiber Wavelength Measurement Systems: Performance Determination Factors, Ginu Rajan, Yuliya Semenova, Agus Hatta, Gerald Farrell

Books/Book Chapters

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