Engineering Commons^™

Characterization And Upgrade Of Endocarp Biomass Derived Lignin To Value Added Products, Makua Vin-Nnajiofor

Theses and Dissertations--Biosystems and Agricultural Engineering

Lignin is an abundant biopolymer and a promising source of feedstock for high-value chemicals and energy materials, however, application methods of lignin into valuable products is yet to be fully explored. This study explores the valorization of lignin derived from lignin-rich endocarp biomass through the development of lignin-derived electrode materials. The chemical composition and cellular structure of the endocarps were characterized using HPLC and scanning electron microscopy (SEM) imaging. Mechanical properties of walnut and peach endocarps and preprocessing requirements were investigated using nanoindentation and specific energy consumption during grinding. Next, lignin was extracted from endocarps using deep eutectic solvent and …

Rees/Aaee Special Focus On Ethics: Introduction By Guest Editor, Shannon Chance, Shannon Chance

Articles

Today, more than ever, we see the significance of ethics in developing and sustaining the built, social, and natural environments around us. We also recognise the need to develop engineering students’ knowledge, skills, and values regarding engineering, innovation, design, production, and the like. Engineers’ actions can have intended as well as unintended consequences, and we as a community need to become more aware of the outcomes and implications of our work. In response to the many topics presented at the REES 2019, the REEN Board selected ethics as the focus for this special issue and joined with AAEE to publish …

Advancement Of Full-Vector Variable-Temperature Magnetometry For Rock-Magnetic And Paleointensity Applications, Leonid Surovitskii

Dissertations, Master's Theses and Master's Reports

Data on the variation of the direction and strength of Earth’s ancient magnetic field (absolute paleointensity) provide crucial information into the mechanisms of the geodynamo and the Earth’s thermal history. However, the use of conventional methods and instrumentation for absolute paleointensity determination has been hampered by physicochemical alteration of the samples caused by multiple high-temperature cycles and long experiment durations. The reliability and efficiency of the measurement process can be improved by the measurement of the full remanent magnetization vector simultaneously with the temperature cycling of a sample. Such as approach can also substantially expand the scope of materials available …

Implementing The Empirical Stone Mine Pillar Strength Equation Into The Boundary Element Method Software Lamodel, Samuel Escobar

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research, the equation for the increasing stress into the interior of a stone mine pillar, as a function of the pillar width-to-height ratio, is derived from the empirical pillar strength equation proposed by Esterhuizen et al. (2011). The gradient stress equations for the stone mine pillars were derived by following similar approaches to those presented by Mark et al. (1992) and Johnson et al. (2014). In these approaches, it is assumed that the variation of stresses within the pillar is a function of distance to the closest rib. The stress gradient function provides the stress distribution within the …

Above And Beyond: Ethics And Responsibility In Civil Engineering, Shannon Chance, Rob Lawlor, Inês Direito Direito, John Mitchell

Articles

This exploratory study investigates how nine London-based civil engineers have enacted ‘global responsibility’ and how their efforts involve ethics and professionalism. The study assesses moral philosophies related to ethics, as well as professional engineering bodies’ visions, accreditation standards, and requirements for continuing professional development. Regarding ethics, the study questions where the line falls between what an engineer ‘must do’ and what ‘would be good to do’. Although the term ethics did not spring to mind when participants were asked about making decisions related to global responsibility, participants’ concern for protecting the environment and making life better for people did, nonetheless, …

Computational Modeling Of Climate Attributes And Condition Deterioration Of Concrete Highway Pavements, Salma Sultana

Electronic Theses and Dissertations

An efficient and safe road network secures the nation’s economy and prosperity by providing public mobility and freight transport. Maintenance and rehabilitation of the road network cost billions of dollars annually. Road and highway infrastructures performance in any country is impacted by load repetitions and it is further compromised by climate attributes and extreme weather events. Damages to roads and bridges are among the infrastructure failures that have occurred during these extreme events. If maintenance and rehabilitation are not done promptly, the damages to the road caused by heavy traffic and extreme climate may lead to life-threatening conditions for road …

A Hydrologic Study Of Climate Variability In Arid Region, Abdullah Alzaydani

Electronic Theses and Dissertations

Climate variability is an important subject to study. It is the change of climate over a long time, which could have a positive or negative impact on humans, soil, and wildlife. Many environments, such as arid environment could be affected by climate variability. The research goal is studying and examining climate variability in arid environment. The research includes three different studies. The first study includes reviewing and understanding of climate variability over extended time through existing studies in arid environments. In addition, this study includes knowledge about climate negative or positive impact on the environment. This study will be reviewing …

Less Commute Miles. Decreased Tire Wear. What Would You Do?, Dylan Schwarz, Brendon M. Ford, Brandon D. Hadinger, Abbie N. Pearce, Jacinta M. Pikunas

Williams Honors College, Honors Research Projects

With the flagrant recognition of the coronavirus as one of those most impactful viruses in the history of the world, it is important to study how the effects of such a disease can create troublesome ripple effects in the world. Covid-19 has caused the death of hundreds of thousands of individuals and has negatively impacted the lives of American’s all across the country during the nationwide lockdown. Decreased work commuters, minimal road travel, and little need for car repairs hit the Goodyear Tire and Rubber Company hard. The University of Akron has teamed up with Goodyear to explore such effects …

Improving Operational Short- To Medium-Range (Sr2mr) Streamflow Forecasts In The Upper Zambezi Basin And Its Sub-Basins Using Variational Ensemble Forecasting, Rodrigo Valdés-Pineda, Juan B. Valdés, Sungwook Wi, Aleix Serrat-Capdevila, Tirthankar Roy

Department of Civil and Environmental Engineering: Faculty Publications

The combination of Hydrological Models and high-resolution Satellite Precipitation Products (SPPs) or regional Climatological Models (RCMs), has provided the means to establish baselines for the quantification, propagation, and reduction in hydrological uncertainty when generating streamflow forecasts. This study aimed to improve operational real-time streamflow forecasts for the Upper Zambezi River Basin (UZRB), in Africa, utilizing the novel Variational Ensemble Forecasting (VEF) approach. In this regard, we describe and discuss the main steps required to implement, calibrate, and validate an operational hydrologic forecasting system (HFS) using VEF and Hydrologic Processing Strategies (HPS). The operational HFS was constructed to monitor daily streamflow …

Joint Carrier Frequency And Phase Offset Estimation Algorithm For Cpm-Dsssbased Secure Point-To-Point Communication, Saima Shehzadi, Farzana Kulsoom, Muhammad Zeeshan, Qasim Umar Khan, Shahzad Amin Sheikh

Turkish Journal of Electrical Engineering and Computer Sciences

A point-to-point (P2P) communication system based on the CPM-DSSS scheme ensures reliability, security, and antijamming capabilities. However, for reliable detection of data carrier synchronization of CPM-DSSS based system is one of the requirements. This paper presents a joint algorithm for carrier frequency offset (CFO) and carrier phase offset (CPO) estimation for CPM-DSSS based P2P system. The results indicate that the proposed CFO estimator is unbiased and can accurately estimate a wide range of offsets. Moreover, the proposed algorithm is compared with another research work. The results show that the proposed CFO and CPO estimation algorithm outperforms its counterpart with a …

Computer Modeling Of Solar Thermal System With Underground Storage Tank For Space Heating, Mohammad Yousef Mousa Naser

Browse all Theses and Dissertations

Space heating is required in almost every dwelling across the country for different periods of time. The thermal energy needed to meet a heating demand can be supplied using different conventional and/or renewable technologies. Solar energy is one example of a renewable resource that can be used for supplying heating needs. It can be utilized either by using photovoltaic panels to generate electricity, that in turn can be used to operate heaters, or by using solar thermal panels. Solar thermal panels obtain higher operating efficiencies than photovoltaic panels, but solar energy for heating purposes suffers from a mismatch between supply …

Geology Oriented Loading Approach For Underground Coal Mines, Deniz Tuncay

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mining-induced stresses in underground coal mines play a significant role in pillar and support design, hence in the safety of mining operations. Adequate design of pillars and roof control plans rely on the accurate assessment of the mining-induced loads, as well as the load-bearing capacities of the supports. In pillar design tools frequently used by the underground coal mining industry and Mine Safety and Health Administration (MSHA), overburden loading is estimated by geometric concepts such as the tributary area and the abutment angle method. These methods do not explicitly consider important mechanical responses such as specific overall ground behavior. The …

Various Operational Aspects Of The Extraction Of Critical Minerals From Acid Mine Drainage And Its Treatment By-Product, Zhongqing Xiao

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid mine drainage (AMD) is environmentally hazardous acidic water, which is continuously generated in large volumes at coal mining sites, typically when pyrite is exposed to oxygen and water. As its continuous migration under the geologic conditions, AMD tends to leach metal elements out from the surrounding minerals, leading to high concentrations of metal elements, like iron, aluminum, magnesium, manganese, lead, arsenic, as well as critical cobalt and rare earth elements (REEs). AMD must be treated and monitored to meet the effluent limits, under U.S.C §1251, the Clean Water act, before being discharged to receiving streams.

Recently, the research is …

The Effect Of Natural Fractures On The Mechanical Behavior Of Limestone Pillars: A Synthetic Rock Mass Approach Application, Mustafa Can Süner

Graduate Theses, Dissertations, and Problem Reports (ETD)

In general, underground limestone mines have inherently strong rock and experience good ground stability. Also, modern pillar design guidelines developed by National Institute for Occupational Safety and Health (NIOSH) have improved the design of stable layouts for modern limestone mines. However, ground control-related incidents are still an important problem. In underground limestone mines, previously mined sections stay open for the life of the mine which may be many years, and it is possible for travel ways to working faces to pass through these old sections. In a recent massive pillar collapse in an old section of a mine in Pennsylvania …

Determination Of Effectiveness Of Energy Management System In Buildings, Vivash Karki

Graduate Theses, Dissertations, and Problem Reports (ETD)

Building Energy Management Systems (BEMS) are computer-based systems that aid in managing, controlling, and monitoring the building technical services and energy consumption by equipment used in the building. The effectiveness of BEMS is dependent upon numerous factors, among which the operational characteristics of the building and the BEMS control parameters also play an essential role. This research develops a user-driven simulation tool where users can input the building parameters and BEMS controls to determine the effectiveness of their BEMS. The simulation tool gives the user the flexibility to understand the potential energy savings by employing specific BEMS control and help …

Wireless Mobile Phone Technology, Deregulation Policy, Competition And Economic Welfare In Nigeria’S Telecom Industry: An Analytic Model, Onochie J. Dieli Phd

Journal of International Technology and Information Management

This analytic model is about the Nigerian telecom industry’s structural change caused by the arrival of a new wireless mobile phone technology. Nigeria’s telecom industry transformed from natural monopoly to competitive market as a result of deregulation that occurred in 1999. Under the price regulation using underground or above the ground cable telephone lines, it could run only with the help of government subsidies. This study argues that the arrival of a new telecomm technology was the key to success of Nigeria’s deregulation of its telecom industry. An analysis of a simple microeconomic model shows that with the new wireless …

Overcoming Team Boundaries In Agile Software Development, Scarlet Rahy, Julian Bass

Journal of International Technology and Information Management

Abstract: The usage of agile software development methods is increasing and so is the need for enhancing the collaboration between the different stakeholders. Thus, we chose to investigate the communication tools and challenges across the different boundaries and consequently deduce implications for practitioners. This research addresses inter-team communication by exploring the practitioners' perception on the different communication tools and the challenges faced at the three different boundaries, inter-team, team and customers, and geographically separated teams. We aim to enhance the productivity of software development through enhancing the communication between the different stakeholders. In this research, we use grounded theory approach …

Surveillance Of Plasticizers, Bisphenol A, Steroids And Caffeine In Surface Water Of River Ganga And Sundarban Wetland Along The Bay Of Bengal: Occurrence, Sources, Estrogenicity Screening And Ecotoxicological Risk Assessment, Paromita Chakraborty, Nancy W. Shappell, Moitraiyee Mukhopadhyay, Sathaporn Onanong, Daniel D. Snow

Daugherty Water for Food Global Institute: Faculty Publications

The transboundary River Ganga serves as a conduit for meltwater from the Himalayas and is a major freshwater source for two thirds of Indian population before emptying into the Sundarban Delta, the largest estuary in the Bay of Bengal. Endocrine disrupting compounds (EDCs) such as phthalic acid esters (PAEs) and bisphenol A (BPA) used as organic plastic additives can pollute the aquatic environment receiving plastic litter. Hence, we have investigated these EDCs in water samples from Ganga and Sundarban wetland of India. Since these compounds exhibit estrogenic potential, we have further measured steroids and evaluated the estrogenic activity (estradiol equivalents, …

Assessment Of A Decentralized Solution For Waste Plastic Management In Developing Regions, Chandniben Ashishkumar Joshi

Theses and Dissertations--Chemical and Materials Engineering

Rapid population growth, urbanization and availability of pre-packaged consumer goods have led to increased generation and consumption of plastic – so much so that it has become ubiquitous in the environment. An affordable, durable, and lightweight material of construction, plastic is used in innumerable products in every country on earth. However, this explosion of consumption coupled with the material’s significantly low degradability have led to serious plastic accumulation challenges, which are now an imminent threat to terrestrial and marine species globally. These challenges are especially acute in developing countries, where capital and infrastructure constraints, poor governmental regulation and lack of …

Assessments Of Chromium Pollution In Surface Sediment Of The Inner Gulf Of Thailand, Patcha Leelakun

Chulalongkorn University Theses and Dissertations (Chula ETD)

The inner Gulf of Thailand is an important marine resource for economic and social developments of Thailand. Moreover, the inner Gulf of Thailand is a diverse of biological coastal ecosystem, which is make an equilibrium marine environment. On the other hand, this area is due mainly to a variety of pollutant sources from the surface runoff, particularly major large rivers including the Mae Klong, the Tha Chin, the Chao Phraya and the Bangpakong Rivers. As a result, chromium contamination can occur in the inner Gulf of Thailand and ultimately become a serious environmental issue in Thailand. Therefore, the surface sediments …

Ecological Risk Assessment Of Microplastics And Heavy Metals In Central Industrial Wastewater Treatment Plant, Thamonwan Phuprasert

Chulalongkorn University Theses and Dissertations (Chula ETD)

Microplastics become a big concern in environment. Their small particle size can absorb a variety of pollutants from the nearby environment when discharged into the environment, especially heavy metals. Central industrial wastewater treatment plant (WWTP) is an important source of microplastics in the environment. In this study, wastewater and sludge were collected from two industrial estates in Thailand. Wastewater was collected from 4 points i.e., influent, post grit chamber, post aeration tank, and post sedimentation tank while sludge was collected from sludge storage. Concentration of microplastics, heavy metals and heavy metals on microplastics were examined to evaluate ecological risk assessment. …

Experimental Investigation And Numerical Modelling Of Biomechanical Variation Of Decomposed Root: An Application Of Vegetated Slope Stability, Trung Nghia Phan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Plant root reinforcement in soil bioengineering has gained increasing interest as a means of sustainable and environmentally friendly soil reinforcement and stabilization. In addition, quantifying evolutions of the biomechanical properties and mechanical root reinforcement to soil with the duration of root decomposition is important to agricultural land-use strategy and to soil stabilization purpose. However, the variations of these properties of the roots of herbaceous species, especially following herbicide application, have rarely been studied. This study aims to comprehensively measure the root morphological traits, root biomechanical properties, and root reinforcement of two contrasting vetiver species (Chrysopogon nemoralis and Chrysopogon zizanioides). In …

Impact Analysis Of Variable Renewable Energy Integration On Total System Costs And Electricity Generation Revenue And Impact Mitigation, Veeraya Imcharoenkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Variable renewable energy (VRE) integration creates additional costs, called integration costs. These costs have grown with VRE penetration, potentially increasing the total system costs delivered to customers (direct integration costs) and decreasing electricity generation revenue, discouraging investment by generators (indirect integration costs). Thus, integration costs can serve as an economic barrier to the integration of high VRE shares. The main objective of this dissertation is to propose a novel method of determining the impacts of VRE integration on total system costs and electricity generation revenue. With this method, the optimal generation mix and optimal generation schedules at the specific VRE …

Site Selection For Feasibility Study Of Pump-Storage Hydropower Project In The Philippines, Sornsawan Utthakrue

Chulalongkorn University Theses and Dissertations (Chula ETD)

Pumped-storage hydropower projects (PSP) are a technology for hydroelectric energy storage. It is a design of two water reservoirs at different elevations that can create electricity as water flows from one to the other via a turbine. The PSP system is similar to a huge battery in that it can store and then release energy as needed. The Philippines is a country with a wide range of elevations due to its island composition. Natural disasters occur frequently, making it challenging to establish any structure. But the PSP is a large building that is also capable of generating a great amount …

Impact Evaluation Of Major Hurricanes On Designated Southeast Coast Counties Of Usa Using Multivariate Analysis And Forecasting, Mukti Patel

All ETDs from UAB

The study includes four major analyses. Each analysis has its own uniqueness. The Temporal analysis intended to track the economic effect trends of major storms in small counties and large metro regions as well as compare how the percent GDP loss in these locations has affected. The study shows that unfavorable impacts of major storms of the same scale and intensity stood the greatest shift in GDP growth rate percentage along with greatest damage in terms of GDP particularly in the smaller counties during and after major storm event. In addition to that percentage change in population growth rate, personal …

Aviation Culture: A ‘Glass Sky’ For Women Pilots - Literature Review, Ivana Gorlin, Donna Bridges

International Journal of Aviation, Aeronautics, and Aerospace

This paper reports on a review of literature covering gender issues in aviation. It considers the impacts of aviation culture on women pilots. The focus of the review was on empirical studies over a 25-year period (1996-2020). Two research questions underpin the review; firstly, we investigated how aviation culture impacts women pilots’ experiences, secondly, we considered its effect on women as pilots. Using a hermeneutic methodological framework, we found that cultural attitudes towards women pilots in the aviation industry are biased and discriminatory. The studies in the review overwhelming concur that the hegemonic masculine culture that dominates aviation significantly diminishes …

Arab American Women In Engineering: How Did Their Culture Influence Their Achievement?, Iktimal Bia Hamed

Master's Theses and Doctoral Dissertations

This body of research examined the Arab American culture and its impact on women who studied the male-dominated major of engineering. Through a qualitative approach, women born and raised in an Arab American home unpacked their experiences since childhood that made them who they are today. The 10 female Arab American participants shared how they made it through and successfully completed their major in engineering. This study focused on engineering, since there has been little to no growth in women who major in this male-dominated subject. This research examined how the participants’ parents, extended family, friends, community, and both K-12 …

Information Retrieval-Based Bug Localization Approach With Adaptive Attributeweighting, Mustafa Erşahi̇n, Semi̇h Utku, Deni̇z Kilinç, Buket Erşahi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Software quality assurance is one of the crucial factors for the success of software projects. Bug fixing has an essential role in software quality assurance, and bug localization (BL) is the first step of this process. BL is difficult and time-consuming since the developers should understand the flow, coding structure, and the logic of the program. Information retrieval-based bug localization (IRBL) uses the information of bug reports and source code to locate the section of code in which the bug occurs. It is difficult to apply other tools because of the diversity of software development languages, design patterns, and development …

Aviation English Assessment And Training, Robert Fowler, Elizabeth Mathews, Jena Lynch, Jennifer Roberts M.A.

Publications

Due to a significant global increase in demand for air travel, there has been a corresponding increase in demand for ab initio flight training. Thousands of international flight students seek admission to collegiate aviation programs in the United States and Canada every year. These international flight students come to the United States and Canada because flight training is nonexistent in their native countries. In fact, flight training in most of these countries is impossible due to airspace restrictions and onerous regulations. If there is flight training available in these countries, the cost is usually prohibitive compared to the cost in …

On The Mandelbrot Set For I**2 = ±1 And Imaginary Higgs Fields, Jonathan Blackledge

Articles

We consider the consequence of breaking with a fundamental result in complex analysisby lettingi2=±1wherei=√−1is the basic unit of all imaginary numbers. An analysis of theMandelbrot set for this case shows that a demarcation between a Fractal and a Euclidean object ispossible based oni2=−1andi2= +1, respectively. Further, we consider the transient behaviourassociated with the two cases to produce a range of non-standard sets in which a Fractal geometricstructure is transformed into a Euclidean object. In the case of the Mandelbrot set, the Euclideanobject is a square whose properties are investigate. Coupled with the associated Julia sets and othercomplex plane mappings, this …