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Articles 541 - 570 of 1134

Full-Text Articles in Engineering

Plastic Pollution, Fall/Winter 2019, Issue 39.3 Aug 2019

Plastic Pollution, Fall/Winter 2019, Issue 39.3

Sustain Magazine

No abstract provided.


Plastic Pollution, Fall/Winter 2019, Issue 39.2 Aug 2019

Plastic Pollution, Fall/Winter 2019, Issue 39.2

Sustain Magazine

No abstract provided.


Plastic Pollution, Fall/Winter 2019, Issue 39 Aug 2019

Plastic Pollution, Fall/Winter 2019, Issue 39

Sustain Magazine

No abstract provided.


Iot Ignorance Is Digital Forensics Research Bliss: A Survey To Understand Iot Forensics Definitions, Challenges And Future Research Directions, Tina Wu, Frank Breitinger, Ibrahim Baggili Aug 2019

Iot Ignorance Is Digital Forensics Research Bliss: A Survey To Understand Iot Forensics Definitions, Challenges And Future Research Directions, Tina Wu, Frank Breitinger, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

Interactions with IoT devices generates vast amounts of personal data that can be used as a source of evidence in digital investigations. Currently, there are many challenges in IoT forensics such as the difficulty in acquiring and analysing IoT data/devices and the lack IoT forensic tools. Besides technical challenges, there are many concepts in IoT forensics that have yet to be explored such as definitions, experience and capability in the analysis of IoT data/devices and current/future challenges. A deeper understanding of these various concepts will help progress the field. To achieve this goal, we conducted a survey which received 70 …


Research Methodology Adopted In Developing Tansse-L System, Ellen Kalinga Jun 2019

Research Methodology Adopted In Developing Tansse-L System, Ellen Kalinga

Tanzania Journal of Engineering and Technology (TJET)

Research methodology is among the very important part in a research work. It is the heart which describe the activities necessary for the completion of the research work. Research methodology provides a plan of investigation considered to obtain answers to research problems and it depends on the context of application. This paper presents the research methodology adopted when developing Tanzania Secondary Schools e-Learning (TanSSe-L) system, a learning management system (LMS) which was successfully developed through customization of Moodle open source LMS. TanSSe-L system is a context centered platform for secondary schools in Tanzania. TanSSe-L system was developed using a number …


Material Flow Analysis As A Decision Supporting Tool For Faecal Sludge Resource Recovery: Mathematical Formulation And Quantification, Isabela Thomas Mkude Jun 2019

Material Flow Analysis As A Decision Supporting Tool For Faecal Sludge Resource Recovery: Mathematical Formulation And Quantification, Isabela Thomas Mkude

Tanzania Journal of Engineering and Technology (TJET)

In this work, a conceptual framework for faecal sludge (FS) management and resource recovery in Dar es Salaam city was developed. Material Flow Analysis (MFA) approach was used to assess and quantify the current materials and nutrients to support on decisions for nutrient recovery and minimize environmental pollution in three unplanned settlements of Manzese, Keko and Kipawa in Dar es Salaam city. Nitrogen and Phosphorus were chosen as indicators for the evaluation of the process. The results showed that about 75% of the Dar es Salaam city population relies on pit latrines and 15% connected to septic tanks, translating to …


Assessment Of Surface Water Resources In Great Ruaha River Sub-Basin Tanzania: Application Of Weap Model For Water Allocation And Utilization Impacts Analysis, Deogratias Mulungu Jun 2019

Assessment Of Surface Water Resources In Great Ruaha River Sub-Basin Tanzania: Application Of Weap Model For Water Allocation And Utilization Impacts Analysis, Deogratias Mulungu

Tanzania Journal of Engineering and Technology (TJET)

The Great Ruaha River (GRR) sub-basin is one of the most important waterways in Tanzania as it supports important economic activities. The sub-basin is progressively faced with an inevitable situation of increasing water demand among competing users while the quantity and quality of water is diminishing. The focus of this study was to assess allocation of existing (2012) and future (up to 2025) quantities of surface water in the GRR sub-basin with consideration of priorities given in the Tanzania Water Resources Management Act, 2009 in the order: domestic, environment, agriculture, livestock and non-domestic. Simulation of water allocation scenarios of irrigation …


Recovery Of Carbonaceous Solid Residue (Char) From Coal Ash To Use As Possible Substitute Graphite-Based Materials In Green Energy Applications, Ana C. Santos, Charlotte J. Badenhorst, Barbara Białecka, Joanna Całus-Moszko May 2019

Recovery Of Carbonaceous Solid Residue (Char) From Coal Ash To Use As Possible Substitute Graphite-Based Materials In Green Energy Applications, Ana C. Santos, Charlotte J. Badenhorst, Barbara Białecka, Joanna Całus-Moszko

World of Coal Ash Proceedings

No abstract provided.


The Santa Clara, 2019-05-09, Santa Clara University May 2019

The Santa Clara, 2019-05-09, Santa Clara University

The Santa Clara

No abstract provided.


Fluoride Removal From Water Using A 3d Printed Calcium Carbonate Filter, Sophia Bakar, David Kahler, Benjamin S. Goldschmidt Apr 2019

Fluoride Removal From Water Using A 3d Printed Calcium Carbonate Filter, Sophia Bakar, David Kahler, Benjamin S. Goldschmidt

Undergraduate Research and Scholarship Symposium

Groundwater containing high concentrations of fluoride is the most common source of drinking water in rural areas in parts of east Africa, India, and China. The elevated levels of fluoride cause skeletal and dental fluorosis, which is the weakening and decay of bone structures due to the leeching of calcium from the body as calcium and fluoride bond by the process of adsorption. Over 150 million people are suffering from some form of fluorosis due to the consumption of groundwater. Calcium carbonate has been demonstrated to influence fluoride removal in several forms. To make fluoride removal a cost-effective and user-friendly …


A Data-Driven Approach For Modeling Agents, Hamdi Kavak Apr 2019

A Data-Driven Approach For Modeling Agents, Hamdi Kavak

Computational Modeling & Simulation Engineering Theses & Dissertations

Agents are commonly created on a set of simple rules driven by theories, hypotheses, and assumptions. Such modeling premise has limited use of real-world data and is challenged when modeling real-world systems due to the lack of empirical grounding. Simultaneously, the last decade has witnessed the production and availability of large-scale data from various sensors that carry behavioral signals. These data sources have the potential to change the way we create agent-based models; from simple rules to driven by data. Despite this opportunity, the literature has neglected to offer a modeling approach to generate granular agent behaviors from data, creating …


Poster Session 1, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Poster Session 1, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • 1.1 Evaluating Soil Characteristics in Rural and Urban Areas
  • 1.2 Use of eDNA in Detection of Multiple Salamander Species in Eastern Kentucky Streams
  • 1.3 Evaluation of biomass and filtration method on eDNA detection of fantail darters (Etheostoma flabellare)
  • 1.4 The Impact of Agricultural Development on Nutrient Contamination Hotspots Within a Small, Intermittent Watershed at EKU’s Meadowbrook Farm, Madison County, Kentucky
  • 1.5 How Does Drought Length Impact the Runoff and Nutrient Storm Response in an Agricultural, Intermittent Catchment in Central Kentucky?
  • 1.6 Analyzing Sanitary Sewer Overflow Sensitivity to Storm Characteristics
  • 1.7 Evaluating Soil Properties in No-Till and Conventional Tillage Systems
  • 1.8 …


The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman Mar 2019

The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The sunlight photochemistry of the organic chromophore pyruvic acid (PA) in water generates ketyl and acetyl radicals that contribute to the production and processing of atmospheric aerosols. The photochemical mechanism is highly sensitive to dissolved oxygen content, [O2(aq)], among other environmental conditions. Thus, herein we investigate the photolysis (λ ≥ 305 nm) of 10–200 mM PA at pH 1.0 in water covering the relevant range 0 ≤ [O2(aq)] ≤ 1.3 mM. The rapid consumption of dissolved oxygen by the intermediate photolytic radicals is monitored in real time with a dissolved oxygen electrode. …


Fischer–Tropsch: Product Selectivity–The Fingerprint Of Synthetic Fuels, Wilson D. Shafer, Muthu Kumaran Gnanamani, Uschi M. Graham, Jia Yang, Cornelius M. Masuku, Gary Jacobs, Burtron H. Davis Mar 2019

Fischer–Tropsch: Product Selectivity–The Fingerprint Of Synthetic Fuels, Wilson D. Shafer, Muthu Kumaran Gnanamani, Uschi M. Graham, Jia Yang, Cornelius M. Masuku, Gary Jacobs, Burtron H. Davis

Center for Applied Energy Research Faculty and Staff Publications

The bulk of the products that were synthesized from Fischer–Tropsch synthesis (FTS) is a wide range (C1–C70+) of hydrocarbons, primarily straight-chained paraffins. Additional hydrocarbon products, which can also be a majority, are linear olefins, specifically: 1-olefin, trans-2-olefin, and cis-2-olefin. Minor hydrocarbon products can include isomerized hydrocarbons, predominantly methyl-branched paraffin, cyclic hydrocarbons mainly derived from high-temperature FTS and internal olefins. Combined, these products provide 80–95% of the total products (excluding CO2) generated from syngas. A vast number of different oxygenated species, such as aldehydes, ketones, acids, and alcohols, are also embedded in this product range. …


The Santa Clara, 2019-02-28, Santa Clara University Feb 2019

The Santa Clara, 2019-02-28, Santa Clara University

The Santa Clara

No abstract provided.


Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth Feb 2019

Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth

Plant and Soil Sciences Faculty Publications

Stony soils are distributed all over the world. The study of their characteristics has gained importance lately due to their increasing use as agricultural soils. The effect that rock fragments exert on the soil hydraulic properties is difficult to measure in situ, and is usually derived from the fine earth properties. However, the corrections used so far do not seem accurate for all types of stony soils. Our objective was to assess the adequacy of estimating the hydraulic properties of a stony soil from the fine earth ones by correcting the latter by the volume occupied by rock fragments. To …


Nanosat Tracking And Identification Techniques And Technologies, Mark A. Skinner Feb 2019

Nanosat Tracking And Identification Techniques And Technologies, Mark A. Skinner

Space Traffic Management Conference

Nanosats (and CubeSats, ‘Smallsats’, etc.) are of order 10 cm in size, and are at or near the limits of what can be tracked and characterized, using existing space surveillance assets. Additionally, given the CubeSat form-factor, they are often launched in large numbers (scores), and can be virtually identical. Thus are they difficult to track and to identify.

We have identified a number of technologies that future nanosat missions could employ that would enhance the trackability and/or identification of their satellites when on-orbit. Some of these technologies require active illumination of the satellite with electromagnetic energy, either in the radio …


Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen Feb 2019

Limits To The World’S Green Water Resources For Food, Feed, Fiber, Timber, And Bioenergy, Joep F. Schyns, Arjen Y. Hoekstra, Martijn J. Booij, Rick J. Hogeboom, Mesfin Mekonnen

Daugherty Water for Food Global Institute: Faculty Publications

Green water––rainfall over land that eventually flows back to the atmosphere as evapotranspiration––is the main source of water to produce food, feed, fiber, timber, and bioenergy. To understand how freshwater scarcity constrains production of these goods, we need to consider limits to the green water footprint (WFg), the green water flow allocated to human society. However, research traditionally focuses on scarcity of blue water––groundwater and surface water. Here we expand the debate on water scarcity by considering green water scarcity (WSg). At 5 × 5 arc-minute spatial resolution, we quantify WFg and the maximum sustainable level to this footprint (WFg,m), …


Theoretical Research On The Ploughing Rock Breaking Properties Of New Conical Pdc Cutter, Ju Pei, Wang Chuanliu Feb 2019

Theoretical Research On The Ploughing Rock Breaking Properties Of New Conical Pdc Cutter, Ju Pei, Wang Chuanliu

Coal Geology & Exploration

The researches on the conical PDC cutter are now focused on numerical simulation, field and laboratory tests, the theoretical analysis on its mechanical properties has not been reported. Therefore, the tensile shear rock breaking mechanism and cutting load distribution characteristics of the conical PDC cutter are described by numerical simulation, the theoretical formula of the cutting load is derived according to the energy balance principle. Results show that comparing with the conventional cylindrical PDC cutter, the rock breaking process of conical PDC cutter is more stable, the cutting load is influenced by the rock properties, the parameters of cutter structure, …


Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker Feb 2019

Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

Pt represents an effective promoter of supported Ni catalysts in the transformation of tristearin to green diesel via decarbonylation/decarboxylation (deCOx), conversion increasing from 2% over 20% Ni/Al2O3 to 100% over 20% Ni-0.5% Pt/Al2O3 at 260 °C. Catalyst characterization reveals that the superior activity of Ni-Pt relative to Ni-only catalysts is not a result of Ni particle size effects or surface area differences, but rather stems from several other phenomena, including the improved reducibility of NiO when Pt is present. Indeed, the addition of a small amount of Pt to the supported Ni …


The Santa Clara, 2019-02-07, Santa Clara University Feb 2019

The Santa Clara, 2019-02-07, Santa Clara University

The Santa Clara

No abstract provided.


Continuous Catalytic Deoxygenation Of Waste Free Fatty Acid-Based Feeds To Fuel-Like Hydrocarbons Over A Supported Ni-Cu Catalyst, Ryan Loe, Yasmeen Lavoignat, Miranda Maier, Mohanad Abdallah, Tonya Morgan, Dali Qian, Robert Pace, Eduardo Santillan-Jimenez, Mark Crocker Jan 2019

Continuous Catalytic Deoxygenation Of Waste Free Fatty Acid-Based Feeds To Fuel-Like Hydrocarbons Over A Supported Ni-Cu Catalyst, Ryan Loe, Yasmeen Lavoignat, Miranda Maier, Mohanad Abdallah, Tonya Morgan, Dali Qian, Robert Pace, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

While commercial hydrodeoxygenation (HDO) processes convert fats, oils, and grease (FOG) to fuel-like hydrocarbons, alternative processes based on decarboxylation/decarbonylation (deCOx) continue to attract interest. In this contribution, the activity of 20% Ni-5% Cu/Al2O3 in the deCOx of waste free fatty acid (FFA)-based feeds—including brown grease (BG) and an FFA feed obtained by steam stripping a biodiesel feedstock—was investigated, along with the structure-activity relationships responsible for Ni promotion by Cu and the structural evolution of catalysts during use and regeneration. In eight-hour experiments, near quantitative conversion of the aforementioned feeds to diesel-like hydrocarbons was achieved. …


Irrigation Water Quality—A Contemporary Perspective, Arindam Malakar, Daniel D. Snow, Chittaranjan Ray Jan 2019

Irrigation Water Quality—A Contemporary Perspective, Arindam Malakar, Daniel D. Snow, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

In the race to enhance agricultural productivity, irrigation will become more dependent on poorly characterized and virtually unmonitored sources of water. Increased use of irrigation water has led to impaired water and soil quality in many areas. Historically, soil salinization and reduced crop productivity have been the primary focus of irrigation water quality. Recently, there is increasing evidence for the occurrence of geogenic contaminants in water. The appearance of trace elements and an increase in the use of wastewater has highlighted the vulnerability and complexities of the composition of irrigation water and its role in ensuring proper crop growth, and …


Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Christopher M. U. Neale, A Cast Of Thousands Jan 2019

Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Christopher M. U. Neale, A Cast Of Thousands

Daugherty Water for Food Global Institute: Faculty Publications

This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through online media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focused …


Analyzing Public View Towards Vaccination Using Twitter, Mahajan Rutuja Jan 2019

Analyzing Public View Towards Vaccination Using Twitter, Mahajan Rutuja

Browse all Theses and Dissertations

Educating people about vaccination tends to target vaccine acceptance and reduction of hesitancy. Social media provides a promising platform for studying public perception regarding vaccination. In this study, we harvested tweets over a year related to vaccines from February 2018 to January 2019. We present a two-stage classifier to: (1) classify the tweets as relevant or non-relevant and (2) categorize them in terms of pro-vaccination, anti-vaccination, or neutral outlook. We found that the classifier was able to distinguish clearly between anti-vaccination and pro-vaccination tweets, but also misclassified many of these as neutral. Using Latent Dirichlet Allocation, we found that two …


A Policy Mechanism For Federal Recommendation Of Security Standards For Mobile Devices That Conduct Transactions, Ariel Huckabay Jan 2019

A Policy Mechanism For Federal Recommendation Of Security Standards For Mobile Devices That Conduct Transactions, Ariel Huckabay

Electronic Theses and Dissertations

The proliferation of mobile devices in the BRIC countries has prompted them to develop policies to manage the security of these devices. In China, mobile devices are a primary tool for payments. As a result, China instituted in 2017 a cyber security policy that applies to mobile devices giving China broad authority to manage cyber threats. The United States has a similar need for a cyber policy. Mobile devices are likely to become a primary payment tool in the United States soon. DHS has also identified a need for more effective security policy in mobile devices for government operations. This …


Santa Clara Magazine, Volume 61 Number 1, Winter 2019, Santa Clara University Jan 2019

Santa Clara Magazine, Volume 61 Number 1, Winter 2019, Santa Clara University

Santa Clara Magazine

14 - IN THE BEGINNING An interview with Santa Clara University President Kevin O’Brien, S.J. on what's next and noticing what we swim in. Matt Morgan

22 - ADAM, EVE, AND THE APPLE If making—and appreciating—art makes us human, what happens when we get help making a masterpiece from something unhuman? Lauren Loftus.

28 - BEDROCK When faced with tough decisions, Santa Clara values stand as good guides, says Leon Panetta ’60, J.D. ’63. Leslie Griffy.


Tolle Lege Works Published In 2019, Mcquade Library Jan 2019

Tolle Lege Works Published In 2019, Mcquade Library

Bibliographies

Compiled Tolle Lege bibliography of works published by members of the Merrimack College Community in 2019. Works include journal articles, books, book chapters, conference presentations and posters, and more.


Cadmium Sulfide-Buffered Pv Systems: Assessing The Environmental, Health, And Economic Impacts, Maqsood Ali Mughal, Rajesh Sharma Jan 2019

Cadmium Sulfide-Buffered Pv Systems: Assessing The Environmental, Health, And Economic Impacts, Maqsood Ali Mughal, Rajesh Sharma

Journal of the Arkansas Academy of Science

As the world’s population continues to grow, global energy crises are expected to rise in the future, thus accelerating the demand for renewable energy technology, particularly solar photovoltaics. The energy sector will face an increasingly complex array of interlocking challenges - technological, environmental, health, economic, and regulatory. In this paper, we study CdS, a widely used buffer material in thin film photovoltaics, to assess and monetize environmental, health, and socio-economic externalities associated with the use of the material. Currently, CdS has a significant advantage over other alternate buffer materials in terms of efficiency and low-cost production of large-area processing of …


Improving The Redundancy Of Knuth?S Balancing Scheme For Packet Transmissionsystems, Elie Ngomseu Mambou, Ebenezer Esenogho, Hendrik Ferreira Jan 2019

Improving The Redundancy Of Knuth?S Balancing Scheme For Packet Transmissionsystems, Elie Ngomseu Mambou, Ebenezer Esenogho, Hendrik Ferreira

Turkish Journal of Electrical Engineering and Computer Sciences

A simple scheme was proposed by Knuth to generate binary balanced code words from any information word. However, this method is limited in the sense that its redundancy is twice that of the full sets of balanced codes. The gap between Knuth?s algorithm?s redundancy and that of the full sets of balanced codes is significantly considerable. This paper attempts to reduce that gap. Furthermore, many constructions assume that a full balancing can be performed without showing the steps. A full balancing refers to the overall balancing of the encoded information together with the prefix. We propose an efficient way to …