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2018

Efficiency

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Full-Text Articles in Engineering

Development And Thermodynamic Analysis Of An Integrated Mild/Partial Gasification Combined Cycle (Impgc) Under Green And Brown Field Conditions With And Without Carbon Capture, Henry A. Long Iii Dec 2018

Development And Thermodynamic Analysis Of An Integrated Mild/Partial Gasification Combined Cycle (Impgc) Under Green And Brown Field Conditions With And Without Carbon Capture, Henry A. Long Iii

University of New Orleans Theses and Dissertations

Coal is a very prominent energy source in the world, but it is environmentally unattractive due to its high sulfur and ash content as well as its alleged contribution towards climate change, but it is affordable, abundant, and has high energy content. Thus, utilizing coal in a cleaner and more efficient way has become necessary. One promising clean coal technology involves fully gasifying coal into synthesis gas, cleaning it, and feeding it into a high-efficiency combined cycle, such as an Integrated Gasification Combined Cycle (IGCC). Inspired by the recent success of warn gas cleanup (WGCU), mild and partial gasification are …


A Comparative Analysis Of Regional Productivity Trends, Michael P. Foley Dec 2018

A Comparative Analysis Of Regional Productivity Trends, Michael P. Foley

Construction Management

Throughout recent decades, the construction industry has suffered considerably from its inability to accurately target and measure key aspects of worker output that hinder productivity most. Much research has been conducted to analyze the factors contributing to labor productivity output at the work face, however, this dissertation is primarily focused on discovering key components of the building process that seem to hinder productivity from the perspective of the general contracting team. This paper’s literature review looks to address historical data relating to productivity difficulties specific to the construction industry, laborers’ productivity dilemma at the work face, and the resulting impact …


A Comparative Analysis Of Regional Productivity Trends, Michael P. Foley Dec 2018

A Comparative Analysis Of Regional Productivity Trends, Michael P. Foley

Construction Management

Throughout recent decades, the construction industry has suffered considerably from its inability to accurately target and measure key aspects of worker output that hinder productivity most. Much research has been conducted to analyze the factors contributing to labor productivity output at the work face, however, this dissertation is primarily focused on discovering key components of the building process that seem to hinder productivity from the perspective of the general contracting team. This paper’s literature review looks to address historical data relating to productivity difficulties specific to the construction industry, laborers’ productivity dilemma at the work face, and the resulting impact …


Comparative Study Of Power Semiconductor Devices In A Multilevel Cascaded H-Bridge Inverter, Kenneth Mordi Dec 2018

Comparative Study Of Power Semiconductor Devices In A Multilevel Cascaded H-Bridge Inverter, Kenneth Mordi

Graduate Theses and Dissertations

This thesis compares the performance of a nine-level transformerless cascaded H-bridge (CHB) inverter with integrated battery energy storage system (BESS) using SiC power MOSFETs and Si IGBTs. Two crucial performance drivers for inverter applications are power loss and efficiency. Both of these are investigated in this thesis. Power devices with similar voltage and current ratings are used in the same inverter topology, and the performance of each device is analyzed with respect to switching frequency and operating temperature. The loss measurements and characteristics within the inverter are discussed. The Saber® simulation software was used for the comparisons. The power MOSFET …


Efficacy Of Virtual Models In A Production Systems Course, Lawrence Whitman, Barbara Chaparro Oct 2018

Efficacy Of Virtual Models In A Production Systems Course, Lawrence Whitman, Barbara Chaparro

Barbara S. Chaparro

Wichita State University has developed an integrated set of virtual reality models of an aircraft assembly line. These models are intended to provide students an ‘artifact’ of industrial and manufacturing engineering by providing a realistic environment for initial learning and application. By utilizing a virtual model of the line, students are able to view the process and interrogate the process details, make changes and observe the effects, and gain a better understanding of the concepts and their interrelationships. This paper presents the method used to assess if virtual models (computer models of a real factory) lead to: improved perception of …


Evaluation Of Heat Efficiency Of Flat Solar Air Heaters, E.S. Abbasov, M.A. Umurzakova Sep 2018

Evaluation Of Heat Efficiency Of Flat Solar Air Heaters, E.S. Abbasov, M.A. Umurzakova

Journal of Tashkent Institute of Railway Engineers

The article discusses the issues of increasing the thermal efficiency of flat solar air collectors. To achieve the goal, the authors propose to use methods of wall intensification of heat transfer (using the diffuser-confusor channels and surfaces with spherical depressions). In the article formulas for calculating the thermal efficiency and the relative thermal performance of the collectors are developed


Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl Jul 2018

Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl

Hans-Joachim Ruff-Stahl

Hybrid electric aircraft are expected to enter the small regional aircraft market within the next two decades. The aim of this study was to investigate if a hybrid electric passenger aircraft with 50 seats can be competitive against the established 100 seat aircraft on short range scheduled flights. The Embraer EMB 145 and EMB 190 regional jets were chosen as benchmarks for that market. A hypothetical hybrid version of the EMB 145 with increased fuel efficiency was tested on a cost per available seat mile (CASM) basis. The t tests confirmed significant (p < 0.05) competitiveness of the hybrid version, while in contrast the conventional 50-seater was significantly more expensive compared to the 100seat aircraft. This indicates that hybrid aircraft could enter the short haul market with a competitive advantage, even against the established 100 seat regional jets.


Solution Of Markshader Tasks Using Unmanned Aircraft Under Open Method Of Development Mineral Deposits, Sh.R. Okhunov Jun 2018

Solution Of Markshader Tasks Using Unmanned Aircraft Under Open Method Of Development Mineral Deposits, Sh.R. Okhunov

Gorniy vestnik Uzbekistana

The аrticle is devoted to the review of modern methods of the mineral deposits used when developing. Possibilities of modern unmanned aerial vehicles for shooting and three-dimensional modeling of surfaces are described.


Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl Jun 2018

Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl

International Journal of Aviation, Aeronautics, and Aerospace

Hybrid electric aircraft are expected to enter the small regional aircraft market within the next two decades. The aim of this study was to investigate if a hybrid electric passenger aircraft with 50 seats can be competitive against the established 100 seat aircraft on short range scheduled flights. The Embraer EMB 145 and EMB 190 regional jets were chosen as benchmarks for that market. A hypothetical hybrid version of the EMB 145 with increased fuel efficiency was tested on a cost per available seat mile (CASM) basis. The t tests confirmed significant (p < 0.05) competitiveness of the hybrid version, while in contrast the conventional 50-seater was significantly more expensive compared to the 100seat aircraft. This indicates that hybrid aircraft could enter the short haul market with a competitive advantage, even against the established 100 seat regional jets.


Solar Electric Immersion Heating Element Fabrication, Logan V. Kregness Jun 2018

Solar Electric Immersion Heating Element Fabrication, Logan V. Kregness

Industrial and Manufacturing Engineering

Believing that cooking with flame is cheaper and more efficient than cooking with electricity, Ugandan citizens have exposed themselves to several health and safety risks, including major respiratory issues through harmful emissions, pollution, and the burning down of many homes. Even though solar electric cooking is cheaper and healthier than cooking with flames in the long run, many Ugandans lack the resources to invest in cooking with electricity.

The Solar Stove student research team, led by Dr. Pete Schwartz, partnered with Aid Africa to bring solar panels and prototype solar electric cooking units to villages in Uganda. Observing how their …


Improving Efficiencies For The Loading And Packaging Departments At San Luis Sourdough, Alexis Bergstrom, Isabella Pereira, Claudia Robinson Jun 2018

Improving Efficiencies For The Loading And Packaging Departments At San Luis Sourdough, Alexis Bergstrom, Isabella Pereira, Claudia Robinson

Industrial and Manufacturing Engineering

San Luis Sourdough, currently has issues with efficiency and standardization in their packaging department, ergonomics problems in the packaging department, shipment accuracy in their loading department, and lacks an organized layout design. As a result, four objectives were designed within a six month period. The first was to create standard operating procedures for the packaging department. To inform this decision time studies were performed before and after creating these SOPs. It was discovered that there was a clear need for the SOPs due to variation in packaging efficiency among new and experienced associates. The second set of time studies showed …


Reducing Overall Overtime Hours Accumulated By San Luis Sourdough, Marie Scholl, Emily Vallejos, Randall Yonce Jun 2018

Reducing Overall Overtime Hours Accumulated By San Luis Sourdough, Marie Scholl, Emily Vallejos, Randall Yonce

Industrial and Manufacturing Engineering

The packaging department of San Luis Sourdough Company was redesigned to increase bread throughput and decrease overtime hours issued to employees. Time studies were performed to get an accurate representation of the average throughput of bread with the current packaging conveyor system. After collecting data and surveying the employees and management, we came up with three design solutions to improve their current packaging system. The first design recommendation has a low-investment and is quick to implement as it pertains to changing the worker’s schedule to alleviate the employees from working long hour shifts while increasing the bread throughput. The second …


The Design Of A Digital Scheduling Solution For Healing Alternatives, Hailey A. Malin, Krista L. Mcallester, Anne E. Shields Jun 2018

The Design Of A Digital Scheduling Solution For Healing Alternatives, Hailey A. Malin, Krista L. Mcallester, Anne E. Shields

Industrial and Manufacturing Engineering

The focus of this senior project is to assist Healing Alternatives, an acupuncture clinic located in San Luis Obispo, in developing a business management software to fit their needs and boost their overall organization. The approach to finding the right fit for this business included assessing their current system while simultaneously investigating other providers. Once alternatives were found that met all of Healing Alternatives’ initial requirements, trial demos were generated in order to perform user experience testing. The presented final solution, a scheduling software called Acuity Scheduling, was implemented in a three-phase move plan that occurred over the period of …


Slm Materials Development, Justin G. Reiner, Michael T. Schembri Jun 2018

Slm Materials Development, Justin G. Reiner, Michael T. Schembri

Industrial and Manufacturing Engineering

The purpose of this project was to create a procedure to efficiently determine a “recipe” of parameter values that create a desired set of mechanical properties. Research was conducted into the laser powder bed fusion process with focus on underdeveloped materials. A design of experiment was used with a set of density correlated parameters to establish a method of producing nearly dense parts. Our methods include SLM printing, metrology, and statistical analysis. An experimental procedure for materials development was designed, but unable to be validated during the scope of this project, due to unforeseen safety issues (exposure to Chromium 6, …


Healing Alternatives Workspace Remodel, Lissandra Ilcyn, Jenifer Astrid Colmenares, Grace E. Kuffner Jun 2018

Healing Alternatives Workspace Remodel, Lissandra Ilcyn, Jenifer Astrid Colmenares, Grace E. Kuffner

Industrial and Manufacturing Engineering

Healing Alternatives is an acupuncture office space located in a repurposed house in San Luis Obispo. Healing Alternatives’ current facility layout does not allow for an additional treatment room or the space to provide additional services because of the wasted space within the facility. Furthermore, patients can be disrupted by noise outside the treatment room causing a negative customer experience. The project team’s objectives are to:

o Design two layout alternatives

o Provide a time estimate for each alternative

o Provide a cost analysis of each alternative

o Implement 5s methodology on the storage room

o Provide a 2D-3D model …


Cal Poly Supermileage Drivetrain, Michael Bolton, Justin Miller, Heather Fields Jun 2018

Cal Poly Supermileage Drivetrain, Michael Bolton, Justin Miller, Heather Fields

Mechanical Engineering

The following report details the full design process used by the Cal Poly Supermileage Drivetrain (CPSMD) Senior Project team in designing a new drivetrain system for the Cal Poly Supermileage Vehicle (SMV) Team. Included is the development stages of each component, the manufacturing of our parts, the final solution’s assembly, the testing of the project, and the results from the 2018 Shell Eco-Marathon Competition. After collecting data from several tests, only the final drivetrain efficiency and final sprocket alignment remain unknown. Otherwise, the project came in under budget, within our weight tolerance, and met all the other design objectives. The …


Analysis Of Improved Multiphase Buck Converter, Usamah Riaz Ahmad, Scott Wu Jun 2018

Analysis Of Improved Multiphase Buck Converter, Usamah Riaz Ahmad, Scott Wu

Electrical Engineering

While the number of transistors per microprocessor is rapidly increasing, the power requirements of converters are getting more and more important. The amount of current is increasing, while at the same time the output voltage is steadily decreasing. Today’s boards are exceeding 100A, while the buck converters have their output voltage below 1 V. Due to these new power requirements, multiphase buck converters are becoming more popular. In addition, this topology is usually used with voltage regulator modules (VRM).

The TPS40090EVM-002 board was used as the original multiphase buck with an input voltage of 12 V and output voltage of …


Suitability Of The Kalina Cycle For Power Conversion From Pressurized Water Reactors, Jack Ryan Webster Jun 2018

Suitability Of The Kalina Cycle For Power Conversion From Pressurized Water Reactors, Jack Ryan Webster

Theses and Dissertations

The primary objective of this work is to determine the Kalina cycle's suitability for thermal power conversion from a pressurized water reactor. Several previous papers have examined this application, but these either lack proof of concept or make unfeasible assumptions. This work expands current knowledge by simulating the Kalina cycle and comparing it to current pressurized water reactor Rankine cycles in order to identify which is more efficient. Prerequisite to the modeling is a simulation tool capable of modeling the thermodynamics of ammonia/water mixtures. Instead of using an existing program, a new one called Clearwater is used. This tool is …


Evaluating The Practices Of A Small Business: A Case Study, Madeleine Anne Bernadicou Jun 2018

Evaluating The Practices Of A Small Business: A Case Study, Madeleine Anne Bernadicou

Construction Management

Companies are in constant search to increase profits. The company success is dependent on its standard operational procedures, otherwise known as SOP. Golden State Irrigation and Noack Pump is a non-union merit shop contractor that performs irrigation work in the California’s central valley. This paper researches the utilized methods of the company to see if it is operating at an optimal level. The methodology used in this project is a case study, where multiple jobs, income statements, and cash flows were analyzed, along with conducted interviews. Both qualitative and quantitative data were collected in the investigation of this case study. …


Thermoelectrics And Thermoelectric Devices, Benjamin T. Erck May 2018

Thermoelectrics And Thermoelectric Devices, Benjamin T. Erck

Senior Theses

The field of thermoelectrics has many applications, and more are found in everyday systems. From its current studies, it is apparent that improving the figure of merit zT (which defines a good thermoelectric material) is important in the effectiveness of power generation. Another important part of thermoelectrics is the duality of these devices. They can both move heat and generate power, depending on their role in the system. In this thesis research, a process was made to test these thermoelectric relationships for a few Peltier devices in order to understand their efficiencies and what systems they can be applied to.


Assisted Switched Reluctance Machines, Amy Robinson May 2018

Assisted Switched Reluctance Machines, Amy Robinson

Honors Scholar Theses

Switched reluctance machine (SRM) modifications in both control schemes and physical design have been steadily increasing in academia to improve machine performance. Assisted switched reluctance machines (ASRMs) are a type of design modification for SRMs. Permanent magnets (PMs) and electromagnetic DC coils (DCC) are being added to the SRM to improve its torque output and overall efficiency. The choice for the design modification has been evolving throughout the decades. The focus has shifted from adding DCC to ASRM to adding PMs to ASRMs. This paper reviews the research trends of ASRMs and includes an analysis of the modified stator yoke …


Implementation Of 5s At A Survey Laboratory In Western Kentucky University, Mercy Akunna Ebuetse Apr 2018

Implementation Of 5s At A Survey Laboratory In Western Kentucky University, Mercy Akunna Ebuetse

Masters Theses & Specialist Projects

5S is a technique used alongside methodologies such as lean, total quality management and six-sigma for continuous improvement and workplace standardization. Nonetheless, despite the upsurge in the implementation of 5S by lean manufacturing facilities and other industries, educational laboratories appear to be lagging. Taking into consideration the benefits of implementing 5S within industry, it has become crucial to replicate the technique in an educational laboratory to obtain equivalent results. To upgrade educational laboratories into industrial laboratories, 5S (sort, set in order, shine, standardize, and sustain) is required to improve the laboratory’s ergonomics that subsequently increases efficiency, productivity, and lessens waste …


Efficiency Improvement Of Fault-Tolerant Three-Level Power Converters, Ramin Katebi, Jiangbiao He, Waqar A. Khan, Nathan Weise Jan 2018

Efficiency Improvement Of Fault-Tolerant Three-Level Power Converters, Ramin Katebi, Jiangbiao He, Waqar A. Khan, Nathan Weise

Electrical and Computer Engineering Faculty Research and Publications

Fault-tolerant power converters play a critical role in the transportation electrification. However, fault-tolerant operation, high efficiency, and low cost usually result in design criteria that have conflicting constraints and goals. The majority of the fault-tolerant power converter topologies presented in the literature confirm these conflicts. In this paper, three types of fault-tolerant neutral-point clamped (NPC) converters are investigated. Various modulation strategies are explored to reduce the losses of the redundant phase leg. The simulation and experimental results show that the Switching Frequency Optimal Phase opposition Disposition modulation strategy is the most effective approach in minimizing the losses in the redundant …


Fundamental Efficiency Limit Of Passive Non-Magnetic Self-Interference Suppression In Full-Duplex Radios, Adam Narbudowicz, Giuseppe Ruvio, Max Ammann, Nicola Marchetti Jan 2018

Fundamental Efficiency Limit Of Passive Non-Magnetic Self-Interference Suppression In Full-Duplex Radios, Adam Narbudowicz, Giuseppe Ruvio, Max Ammann, Nicola Marchetti

Conference Papers

Passive non-magnetic self-interference suppression circuits are currently used as first stages of complex full-duplex radio systems that allow simultaneous reception and transmission within the same channel. This paper introduces the upper efficiency limit for such circuitry. It is demonstrated that for these devices it is not feasible to have simultaneously high efficiency, good transmitter-to-receiver isolation and same propagation channel for transmission and reception. More specifically, the maximum efficiency for most typical case cannot exceed 50% if good isolation is obtained.


Power Loss Comparison Of Dc Side And Ac Side Cascaded Modular Multilevel Inverters, Shahab Sajedi, Malabika Basu, Michael Farrell Jan 2018

Power Loss Comparison Of Dc Side And Ac Side Cascaded Modular Multilevel Inverters, Shahab Sajedi, Malabika Basu, Michael Farrell

Conference papers

High-voltage DC (HVDC) transmission systems

based on voltage source converter technology are increasingly being used for interconnecting power networks and for transporting energy from remote renewable energy sources. Modular multilevel converters (MMCs) are emerging as the technology of choice for future HVDC transmission systems. Several MMC topologies have been introduced for high power applications and among them the AC side and the DC side cascaded topologies have received most interest because of their high efficiency, low switching losses and good modularity. In high power applications, the efficiency of the converter is an important consideration. Hence it is essential converter power …


Electrical Response Of Thermoelectric Generator To Geometry Variation Under Transient Thermal Boundary Condition, Elias Yazdanshenas, Alireza Rezania, Meysam Karami Rad, Lasse Rosendahl Jan 2018

Electrical Response Of Thermoelectric Generator To Geometry Variation Under Transient Thermal Boundary Condition, Elias Yazdanshenas, Alireza Rezania, Meysam Karami Rad, Lasse Rosendahl

Mechanical & Aerospace Engineering Faculty Publications

A three-dimensional numerical model is applied in this study to illustrate the electrical response of a thermoelectric generator (TEG) during transient heat flux at the hot side. In this work, various types of thermal boundary conditions are considered to evaluate the performance of the TEG. Thus, a TEG under pulsed heat flux is studied numerically, and the numerical model is verified by experimental results. With the consideration of a defined reference geometry, different heat flux frequencies are applied in order to evaluate the corresponding electrical output by the TEG. In addition, variation of the module performance for various TEG leg …


Experimental Design, Testing, And Evaluation Of Methods To Improve The Efficiency And Reduce Emissions From A Small Two-Stroke Natural Gas Engine, Christopher Joseph Ulishney Jan 2018

Experimental Design, Testing, And Evaluation Of Methods To Improve The Efficiency And Reduce Emissions From A Small Two-Stroke Natural Gas Engine, Christopher Joseph Ulishney

Graduate Theses, Dissertations, and Problem Reports

Decentralized power generation is a research area of interest due to possible improvements in electrical generation efficiency and grid resilience. Two-stroke engines are simple, inexpensive, power dense systems that could serve as the prime-movers for combined heat and power (CHP) systems. In addition, such systems could be fueled on natural gas (NG) that is readily available to serve as a reliable fuel source in most households. However, most two-stroke engines are inefficient and produce excessive emissions. This research focused on methods to simultaneously improve engine efficiency and decrease emissions from a 34 cc air-cooled, two-stroke engine retrofitted to operate on …


Irrigation Pumps - Preserving Performance, Derrel L. Martin Jan 2018

Irrigation Pumps - Preserving Performance, Derrel L. Martin

Department of Biological Systems Engineering: Conference Presentations and White Papers

This paper describes how pumps must be matched to operating conditions and power units to provide the desired performance and efficiency. We have recently seen installations where one or more components are not properly matched causing higher than necessary pumping costs. Inspection and maintenance of systems and measurement of flow and pressure will go a long way toward monitoring if the proper conditions are being met. This paper also covers types of pumps, pump components, pump curves, impeller speed and trim, pump staging, affinity laws, pump drives, power units, cavitation, and net positive suction head.


A Review Of Latest Developments, Progress, And Applications Of Heat Pipe Solar Collectors, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati Jan 2018

A Review Of Latest Developments, Progress, And Applications Of Heat Pipe Solar Collectors, Abdellah Sharifian, Mehdi Khiadani, Ataollah Nosrati

Research outputs 2014 to 2021

Among all the available solutions to the current high energy demand and consequent economic and environmental problems, solar energy, without any doubt, is one of the most promising and widespread solutions. However, conventional solar systems face some intractable challenges affecting their technical performance and economic feasibility. To overcome these challenges, increasing attention has been drawn towards the utilization of heat pipes, as an efficient heat transfer technology, in conventional solar systems. To the authors’ knowledge, despite many valuable studies on heat pipe solar collectors (mainly during the last decade), a comprehensive review which surveys and summarizes those studies and identifies …