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Full-Text Articles in Engineering

Series Solution Of The Autocatalytic Hydrolysis Of Cellulose, Rou-Xi Chen, Zhi Liu, Ji-Huan He Dec 2104

Series Solution Of The Autocatalytic Hydrolysis Of Cellulose, Rou-Xi Chen, Zhi Liu, Ji-Huan He

Ji-Huan He

The chemical degradation kinetics of
cellulose is of scientific interest, as well as its practical
importance in many industrial activities for optimal
design. Much work has been done recently to understand
the depolymerizaton of cellulose in homogeneous
acidic medium on the assumption of
autocatalytic hydrolysis with a positive feedback of
acid production from the degraded biopolymer. Series
solutions are obtained for concentrations of cellulose
chains and degraded cellulose chains by Taylor series
and variational iteration method. Depolymerization of
cellulose strongly depends upon the initial conditions,
and the concentration of cellulose chains changes
exponentially with a linear and square/cubic time ...


An Analysis Of The Barriers To And Drivers Of Green Public Procurement In Achieving A More Sustainable Construction Industry, Myles Keaveney, Paul Butler Mar 2104

An Analysis Of The Barriers To And Drivers Of Green Public Procurement In Achieving A More Sustainable Construction Industry, Myles Keaveney, Paul Butler

Conference papers

The public sector in Ireland possesses enormous purchasing power which has the strength to affect production and consumption trends in all market sectors. Environmental purchasing tools such as Green Public Procurement (GPP) are seen by many as the solution to greener purchasing decisions in order to obtain and maintain not only a more sustainable construction sector but also a more sustainable economy. The purpose of this research is to determine and examine the key barriers to and drivers of implementing GPP in public procurement departments in order to reduce the effect construction works have on the environment. There was limited ...


Design Of Microwave Lowpass Filters Based On Metamaterial Components, Mushtaq Ahmed Dec 2103

Design Of Microwave Lowpass Filters Based On Metamaterial Components, Mushtaq Ahmed

Mushtaq A. Alqaisy

No abstract provided.


Cmmi High Maturity, Jack Calis Jan 2021

Cmmi High Maturity, Jack Calis

Jack Calis

Software Education Service in Asia, Europe and Africa, CMMI High Maturity based process of software process consultants and training in by CMMI-High Maturity.


Csar 62 Spin Curve, Mohsen Azadi, Georgia Griggs, Glen De Villafranca, Gerald Lopez Dec 2018

Csar 62 Spin Curve, Mohsen Azadi, Georgia Griggs, Glen De Villafranca, Gerald Lopez

Protocols and Reports

No abstract provided.


Jpk.Pdf, Jpk Sonick Sep 2018

Jpk.Pdf, Jpk Sonick

jpk sonick

Kami menerima jasa refill tabung pemadam kebakaran untuk berbagai merk yang berada di pasaran dan untuk berbagai media


Icdcs2018_Dumitru_Paper_1243.Pdf, Ion Dumitru Jul 2018

Icdcs2018_Dumitru_Paper_1243.Pdf, Ion Dumitru

Ion Dumitru

Remedial work for an iconic building in Sydney, Australia is currently being carried out. Two façade mortars, capable of matching the current exposed quartz aggregate finish and achieving a 40 years design life, are required. In order to ensure the quality of the imported quartz aggregates for this project, test have been carried out for particle size distribution, density, wet/dry strength variation, sodium sulphate soundness and Los Angeles Abrasion value. The two mortar mixes employed for repair work (Form & Pour and Hand Applied mixes) were comprehensively assessed for mix workability, compressive strength in warm and cold conditions, drying shrinkage ...


Systems Engineering Analysis For Optimum Selection Protocol For Thermal Expansion Measurement Of A Carbon Fiber Reinforced Composite Tube, Ronald Uchimiya Jul 2018

Systems Engineering Analysis For Optimum Selection Protocol For Thermal Expansion Measurement Of A Carbon Fiber Reinforced Composite Tube, Ronald Uchimiya

LMU/LLS Theses and Dissertations

A material’s Coefficient of Thermal Expansion (CTE) is a valuable physical property, particularly for structural fiber reinforced composites that are routinely used in satellite/aerospace applications. Satellite space structures are routinely designed with a high degree of dimensional and thermal stability. Designing and verifying for near zero CTE performance is a common design requirement. The CTE is routinely a physical property with known values for common materials. However, the strength, stiffness and CTE properties on a multi-ply graphite fiber reinforced laminate composite can be tailored to specific engineering requirements. Because of this, a method of verification (testing) is routinely ...


Development Of Carbon Fiber-Modified Electrically Conductive Concrete For Implementation In Des Moines International Airport, Alireza Sassani, Halil Ceylan, Sunghwan Kim, Ali Arabzadeh, Peter C. Taylor, Kasthurirangan Gopalakrishnan Jun 2018

Development Of Carbon Fiber-Modified Electrically Conductive Concrete For Implementation In Des Moines International Airport, Alireza Sassani, Halil Ceylan, Sunghwan Kim, Ali Arabzadeh, Peter C. Taylor, Kasthurirangan Gopalakrishnan

Civil, Construction and Environmental Engineering Publications

This paper reports on the procedures of mix design preparation, production, placement, and performance evaluation of the first electrically conductive concrete (ECON) heated-pavement system (HPS) implemented at a U.S. airport. While ECON has drawn considerable attention as a paving material for multi-functional pavements, including HPS, the majority of ECON HPS applications and studies have been limited to laboratory scale or include materials/methods that do not conform to regulations enforced by airfield construction practices. Carbon fiber-reinforced ECON provides a promising prospective for application in airfield pavements. In this study, ECON mixtures were prepared in the laboratory using varying cementitious ...


Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor May 2018

Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor

All Graduate Theses and Dissertations

The design of an aircraft wing often involves the use of mathematical methods for simultaneous aerodynamic and structural design. The goal of many of these methods is to minimize the drag on the wing. A variety of computer models exist for this purpose, but some require the use of expensive time and computational resources to give meaningful results. As an alternative, some mathematical methods have been developed that give reason ably accurate results without the need for a computer. However, most of these methods can only be used for wings with specific shapes and payload distributions. In this thesis, a ...


Evaluating Water Filtration And Disinfection For Household, Using Slow Sand Filters Plus Solar Disinfection, Mariana Demitry May 2018

Evaluating Water Filtration And Disinfection For Household, Using Slow Sand Filters Plus Solar Disinfection, Mariana Demitry

All Graduate Theses and Dissertations

In this research, a household water treatment system was built and evaluated as a trial for improving the drinking water quality of the Nile River for the low-income communities. The system consisted of household-scale slow sand filters, and transparent polyethylene terephthalate-bottles for solar disinfection. The evaluation of the system depended on the removal/inactivation of some surrogates for the reference pathogens, and turbidity. The reference pathogens are pathogens specified by the World Health Organization to evaluate the efficiency of the household water treatment options. They were chosen to represent the classes of pathogens in water (bacteria, viruses, protozoa). The surrogates ...


Evaluating The Impact Of External Carbon Source In Laboratory-Based Denitrification Rate Experiments, Jared Richens May 2018

Evaluating The Impact Of External Carbon Source In Laboratory-Based Denitrification Rate Experiments, Jared Richens

All Graduate Theses and Dissertations

Limitations in the quality of transformation rates used with water quality models such as QUAL2K have led to the need to identify methods that can effectively and accurately determine these rates. During the early stages of method development of a Utah Department of Environmental Quality (Utah DEQ) funded project seeking to identify such methods, it was determined that under certain situations external carbon amendment may be required to successfully determine denitrification rates.

The focus of this study was to evaluate the potential impacts that introducing external carbon sources may have on estimating the laboratory denitrification rates resulting from these methods ...


Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall May 2018

Thrust Augmented Nozzle For A Hybrid Rocket With A Helical Fuel Port, Joel H. Marshall

All Graduate Theses and Dissertations

A thrust augmented nozzle for hybrid rocket systems is investigated. The design lever-ages 3-D additive manufacturing to embed a helical fuel port into the thrust chamber of a hybrid rocket burning gaseous oxygen and ABS plastic as propellants. The helical port significantly increases how quickly the fuel burns, resulting in a fuel-rich exhaust exiting the nozzle. When a secondary gaseous oxygen flow is injected into the nozzle downstream of the throat, all of the remaining unburned fuel in the plume spontaneously ignites. This secondary reaction produces additional high pressure gases that are captured by the nozzle and significantly increases the ...


Size-Scale Effects Of Nonlinear Weir Hydraulics, Nathan L. Young May 2018

Size-Scale Effects Of Nonlinear Weir Hydraulics, Nathan L. Young

All Graduate Theses and Dissertations

Experimental physical model studies of hydraulic structures are often conducted to replicate flow behavior that may occur at the prototype scale. Geometric similitude is most often maintained between the prototype and model when studying reservoir and open channel hydraulic structures to account for the dominant gravity and inertia forces while other fluid forces (e.g., viscosity,surface tension) are assumed negligible. However, as model size and/or upstream head decreases, other fluid forces can exceed the negligible level and influence model flow behavior. This phenomenon is referred to as size-scale effects and is one potential origin of error in predicting ...


Advancing The Implementation Of Hydrologic Models As Web-Based Applications, Prasanna Dahal May 2018

Advancing The Implementation Of Hydrologic Models As Web-Based Applications, Prasanna Dahal

All Graduate Theses and Dissertations

Deeper understanding of relationships between flow in river sand various hydrologic elements such as rainfall, land use, and soil type is imperative to solve water related problems like droughts and floods. Advanced computer models are becoming essential in helping us understand such relationships. However, preparing such models requires huge investment of time and resources, much of which are concentrated on acquisition and curation of data. This work introduces agree and open source web Application (web App) that provides researchers with simplified access to hydrological data and modeling functionality. The web App helps in the creation of both hydrologic models, and ...


Characterization Of Carbon Nanostructured Composite Film Using Photothermal Measurement Technique, Kurt E. Harris May 2018

Characterization Of Carbon Nanostructured Composite Film Using Photothermal Measurement Technique, Kurt E. Harris

All Graduate Theses and Dissertations

Graphene is a form of carbon with unique thermal and structural properties, giving it high potential in many applications, from electronics to driveway heating. Advanced fabrication techniques putting small, graphene-like structures in a polymer matrix could allow for incorporation of some of the benefits of graphene into very lightweight materials, and allow for broader commercialization. Measuring the thermal properties of these thin-film samples is a technical capability in need of development for use with the specific specimens used in this study. Relating those thermal properties to the microstructural composition was the focus of this work.

Several conclusions could be drawn ...


Simulation And Optimization Models To Evaluate Performance Of Aquifer Storage And Recovery Wells In Fresh Water Aquifers, Ali Forghani May 2018

Simulation And Optimization Models To Evaluate Performance Of Aquifer Storage And Recovery Wells In Fresh Water Aquifers, Ali Forghani

All Graduate Theses and Dissertations

Aquifer storage and recovery (ASR) involves artificially recharging an aquifer through well(s) using surplus water for later recovery in high-demand months. The operators of the studied ASR system developed the system as a means of receiving additional water rights to supplement their pre-existing water rights for extraction in dry months. However, the region’s water regulators define the performance of this ASR system as the amount of the injected water that is recoverable from the same wells during extraction periods. The study proposes recovery effectiveness (REN) as the performance index of this ASR system. REN equals the injectate proportion ...


Integrated Systems Modeling To Improve Watershed Habitat Management And Decision Making, Ayman H. Alafifi May 2018

Integrated Systems Modeling To Improve Watershed Habitat Management And Decision Making, Ayman H. Alafifi

All Graduate Theses and Dissertations

Regulated rivers provide opportunities to improve habitat quality by managing the times, locations, and magnitudes of reservoir releases and diversions across the watershed. To identify these opportunities, managers select priority species and determine when, where, and how to allocate water between competing human and environmental users in the basin. Systems models have been used to recommend allocation of water between species. However, many models consider species’ water needs as constraints on instream flow that is managed to maximize human beneficial uses. Many models also incorporate uncertainty in the system and report an overwhelmingly large number of management alternatives. This dissertation ...


Modelling The Influence Of Crop Density And Weather Conditions On Field Drying Characteristics Of Switchgrass And Maize Stover Using Random Forest, Amit Khanchi, Stuart J. Birrell, Robert B. Mitchell May 2018

Modelling The Influence Of Crop Density And Weather Conditions On Field Drying Characteristics Of Switchgrass And Maize Stover Using Random Forest, Amit Khanchi, Stuart J. Birrell, Robert B. Mitchell

Agricultural and Biosystems Engineering Publications

Field drying trials were conducted using both field baskets as well as grab sampling techniques to study drying behaviour of switchgrass and maize (corn) stover (CS). Environmental conditions such as hourly solar radiation, vapour pressure deficit (VPD), average wind speed, rainfall amount, harvesting method, and field operations such as swath density were used as variables for model development. A powerful classification-based algorithm, which uses a collection of decision trees called random forest (RF) was utilised to predict moisture content (MC) of switchgrass and CS on wet basis. RF predicted the MC of switchgrass and CS with a coefficient of determination ...


Enhancement Of Dibenzothiophene Hydrodesulphurization Via Hydrogenation Route On Nimow Catalyst Supported On Hms Modified With Ti, Rafael Maya-Yescas Apr 2018

Enhancement Of Dibenzothiophene Hydrodesulphurization Via Hydrogenation Route On Nimow Catalyst Supported On Hms Modified With Ti, Rafael Maya-Yescas

Rafael Maya-Yescas

This study shows that ternary Ni-Mo-W sulfide catalysts supported on hexagonal mesoporous silica modified with Ti (HMS-Ti) showed a high enhancement of dibenzothiophene (DBT) transformation via hydrogenation route with respect to their Ti-free counterpart. The reaction of hydrodesulphurization (HDS) of DBT was carried out at in a batch reactor at 320 °C and 5.5 MPa of total H2 pressure. The catalysts were characterized by a variety of techniques (chemical analysis, N2 adsorption-desorption isotherms, low- and wide-angles XRD, TPR, TPDNH, DRS UV–vis, TPO/TG and HRTEM). At reaction time of 5 h, all synthetized catalysts exhibited higher DBT conversion ...


The Sustainable Future Of Cross-Modal Transportation And Container Supply Chain Through The Augmented Reality, Sajjad Khaksari Apr 2018

The Sustainable Future Of Cross-Modal Transportation And Container Supply Chain Through The Augmented Reality, Sajjad Khaksari

SAJJAD KHAKSARI

Idea Abstract
The history of innovation in human life is full of the fantastic incremental ideas which sometimes resembled and aspired from an ancient contraption, or sought out through a futuristic idea but what is important is that they always attempt to illuminate and illustrate better expectations. However, concerning the Cross-modal freight transportation and European intermodal container logistics, reducing the time hesitating and minimizing the idling time is one of the compelling arguments. Unfortunately, the Cross-modal transportation still suffers from the series of factors those increase the intermodal delivery time in practical working life. 

In such circumstances, "The Sustainable Future ...


Hybrid Sensorless Field Oriented And Direct Torque Control For Variable Speed Brushless Dc Motors, Kellen Carey Apr 2018

Hybrid Sensorless Field Oriented And Direct Torque Control For Variable Speed Brushless Dc Motors, Kellen Carey

Master's Theses (2009 -)

The objective of this thesis is to design a hybrid sensorless closed-loop motor controller using a combination of Field-Oriented Control (FOC) and Direct Torque Control (DTC) for brushless DC motors used in multi-rotor aerial vehicles. The primary challenge is the wide range of desired working speeds, which can quickly vary from low speed to high speed. For this range, the control approach must be efficient, effective, and low-cost in order to provide fast response times during initial startup, steady-state, and transient operation. Additional design challenges include minimal response time to desired speed changes and small steady-state speed errors. Finally, the ...


Open Source 3d Printers: An Appropriate Technology For Building Low Cost Optics Labs For The Developing Communities, Jephias Gwamuri, Joshua M. Pearce Mar 2018

Open Source 3d Printers: An Appropriate Technology For Building Low Cost Optics Labs For The Developing Communities, Jephias Gwamuri, Joshua M. Pearce

Joshua M. Pearce

The recent introduction of RepRap (self-replicating rapid prototyper) 3-D printers and the resultant open source technological improvements have resulted in affordable 3-D printing, enabling low-cost distributed manufacturing for individuals. This development and others such as the rise of open source-appropriate technology (OSAT) and solar powered 3-D printing are moving 3-D printing from an industry based technology to one that could be used in the developing world for sustainable development. In this paper, we explore some specific technological improvements and how distributed manufacturing with open-source 3-D printing can be used to provide open-source 3-D printable optics components for developing world communities ...


3-D Printing Open-Source Click-Muac Bands For Identification Of Malnutrition, Ross Michaels, Joshua M. Pearce Mar 2018

3-D Printing Open-Source Click-Muac Bands For Identification Of Malnutrition, Ross Michaels, Joshua M. Pearce

Joshua M. Pearce

No abstract provided.


A Hybrid Dynamical Extension Of Averaging And Its Application To The Analysis Of Legged Gait Stability, Avik De, Samuel A. Burden, Daniel E. Koditschek Mar 2018

A Hybrid Dynamical Extension Of Averaging And Its Application To The Analysis Of Legged Gait Stability, Avik De, Samuel A. Burden, Daniel E. Koditschek

Departmental Papers (ESE)

We extend a smooth dynamical systems averaging technique to a class of hybrid systems with a limit cycle that is particularly relevant to the synthesis of stable legged gaits. After introducing a definition of hybrid averageability sufficient to recover the classical result, we illustrate its applicability by analysis of first a one-legged and then a two-legged hopping model. These abstract systems prepare the ground for the analysis of a significantly more complicated two legged model—a new template for quadrupedal running to be analyzed and implemented on a physical robot in a companion paper. We conclude with some rather more ...


On Condition Monitoring Of High Switching Frequency Power Gan Converters With Adaptive Prognostics.Pdf, Mehrdad Biglarbegian Mar 2018

On Condition Monitoring Of High Switching Frequency Power Gan Converters With Adaptive Prognostics.Pdf, Mehrdad Biglarbegian

Mehrdad Biglarbegian

There is no doubt that in the future, a need for higher switching frequency is inevitable to extract the full benefits of reliable Gallium Nitride (GaN) device characteristics. Along with the reliability enhancement for GaN-based power converters, it is essential to monitor a precursor signature identification for diagnostics/prognostics techniques. With the availability of the most granular information deduced from advanced devices, a new data-driven scheme is proposed for system monitoring and possible lifetime extension of 400W power GaN converters at 100kHz. The approach relies on the real-time R_ds(on) data extraction from the power converter, and calibration of an ...


Multi-Purpose Generic Board For Hands-On Power Electronics Education Of Different Power Converter Topologies In Pv Applications.Pdf, Mehrdad Biglarbegian Mar 2018

Multi-Purpose Generic Board For Hands-On Power Electronics Education Of Different Power Converter Topologies In Pv Applications.Pdf, Mehrdad Biglarbegian

Mehrdad Biglarbegian

This paper presents the development of a multi-purpose generic board for hands-on power electronics education lab session focusing on Photovoltaic (PV) power electronics applications. The presented work tries to apply advanced methods for circuit designs and firmware developments of a DC/DC and a DC/AC converter for helping students to get familiar with system/subsystem level learning. The developed advanced converters can be used for interconnection of low voltage PV systems. Besides, the objective is to expedite the transferring of theory to practical purposes and to provide hands-on experiences for the development of power electronics systems.


Development Of Isolated Sensegan Current Monitoring For Boundary Conduction Mode Control Of Power Converters, Mehrdad Biglarbegian Mar 2018

Development Of Isolated Sensegan Current Monitoring For Boundary Conduction Mode Control Of Power Converters, Mehrdad Biglarbegian

Mehrdad Biglarbegian

This paper presents the design of the Isolated SenseGaN (Iso-SenseGaN) current sensing technique using Gallium Nitride (GaN) transistors. The isolation technique for the SenseGaN brings an opportunity for integration of sensing element with the power modules, and enables many control schemes in power converters. This could effectively open broader area for smart device monitoring, implementation of current controlling techniques at high frequency, and proper feedback for diagnostics/prognostics developments. In this work, the focus is on the practical challenges for the SenseGaN technique and presenting the inductor-based galvanic isolation. Using the current mirroring method, the authors defined a cursor for ...


Autonomous Vehicles And The City:, William W. Riggs, Michael R. Boswell, Shivani Shukla, Matthew Kawashima, Therese Perez Mar 2018

Autonomous Vehicles And The City:, William W. Riggs, Michael R. Boswell, Shivani Shukla, Matthew Kawashima, Therese Perez

William W. Riggs

Development of the autonomous vehicles (AVs) offers, perhaps, the most groundbreaking and revolutionary change in the way cities are built and function since the advent of the car. AVs present new opportunities to connect individuals to jobs and change the way cities organize space and optimize trips... .. there are also undeniable risks regarding the design and land use, social, and economic implications associated with their expansion... To begin to address these challenges, in November 2017, a panel of policy makers, planners, designers, developers, and other industry experts gathered at the University of San Francisco to discuss the role AVs will ...


Helipad Design And Best Practices, Andrew Swanson Mar 2018

Helipad Design And Best Practices, Andrew Swanson

Purdue Road School

Heated Permeable Concrete Helipads for Safety and Surety - The latest in helipad construction technologies has combined with aeronautical consultant-guided design to create helipads that are safe and environmentally friendly and that meet the guidelines of the FAA, state, local agencies, and first responders. Join us to learn about heated permeable concrete helipads, which offer safety to flight crew, patient, and helicopter by eliminating ice and snow on the pad and pathways.