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2015

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Full-Text Articles in Engineering

Power Protection Analysis For A Ten Bus System, Sean Hanna Dec 2015

Power Protection Analysis For A Ten Bus System, Sean Hanna

Electrical Engineering

Each power system built in the industry requires a protection plan. Undetected faults in a power system can contribute to hazardous conditions, overheating of power devices, low or high system voltages, unbalanced conditions, and blackouts. This senior project is the design of a protection plan for a power system using the software Electric Transient Analyzer Program (ETAP). With ten buses, five transformers, two generators, two motors, and six transmission lines, there are many possibilities for a fault to occur. The Load flow and fault analysis are studied before the system is protected. All components of the system are protected using …


Mohat Tool To Illustrate Diode And Transistor Modes Of Operation Using Ltspice, Getu D. Engdaw Dec 2015

Mohat Tool To Illustrate Diode And Transistor Modes Of Operation Using Ltspice, Getu D. Engdaw

Electrical Engineering

This project develops a tool to identify the modes of operation of diodes and transistors in a circuit. The MoHAT tool receives schematics or circuit files generated from LTspice, and it determines the state of each diode and transistor. This tool illustrates diodes, BJT and MOS regions of operations using text or graphics accordingly. The tool also suggests necessary adjustments to switch from one mode of operation to another upon users request. Furthermore, the tool specifies if a transistor functions in amplification region. The MoHAT tool compares the nodal voltages of an element and determines the mode of operation.


Utilization Of High Efficient Single Phase Motor, Kevin Hua Dec 2015

Utilization Of High Efficient Single Phase Motor, Kevin Hua

Electrical Engineering

A Smith Motor is a three phase induction motor that has shunt capacitors parallel to its induction coils. The shunt capacitors provide balance and allow the motor to operate using a single phase power supply. Preliminary studies show that the Smith Motor is more efficient than a single phase induction motor powered by a single phase power supply, but less efficient than a three phase induction motor powered by a three phase power supply. The Smith Motor’s advantage is its ability to operate from a single phase power source instead of having a three phase power source installed. Its limitation …


Comparative Analysis Of Buckling-Restrained Braced Frames In Eccentric Configuration (Brbf-Es) And Eccentrically Braced Frames (Ebfs), Peter T. Vayda Dec 2015

Comparative Analysis Of Buckling-Restrained Braced Frames In Eccentric Configuration (Brbf-Es) And Eccentrically Braced Frames (Ebfs), Peter T. Vayda

Civil Engineering Undergraduate Honors Theses

Continuing on the findings of “Using Buckling-Restrained Braced Frames in Eccentric Configuration,” by Dr. Gary S. Prinz, P.E., which determined that, from a performance standpoint, BRBF-Es could be a viable alternative for EBFs. A comparative analysis was conducted on the design procedures and initial cost estimates of BRBF-Es and EBFs. Upon designing four 12-Story buildings (two BRBF-Es and two EBFs), it was determined that BRBF-Es were easier to design due to the statically determinant system. The initial costs estimates of BRBF-Es; however, ranged upwards of 30% more cost than EBFs. Therefore, the initial investment of more intensive structural engineering design …


A Network Topology Control And Identity Authentication Protocol With Support For Movable Sensor Nodes, Ying Zhang, Wei Chen, Jixing Liang, Bingxin Zheng, Shengming Jiang Dec 2015

A Network Topology Control And Identity Authentication Protocol With Support For Movable Sensor Nodes, Ying Zhang, Wei Chen, Jixing Liang, Bingxin Zheng, Shengming Jiang

Computer Science Faculty Research

It is expected that in the near future wireless sensor network (WSNs) will be more widely used in the mobile environment, in applications such as Autonomous Underwater Vehicles (AUVs) for marine monitoring and mobile robots for environmental investigation. The sensor nodes’ mobility can easily cause changes to the structure of a network topology, and lead to the decline in the amount of transmitted data, excessive energy consumption, and lack of security. To solve these problems, a kind of efficient Topology Control algorithm for node Mobility (TCM) is proposed. In the topology construction stage, an efficient clustering algorithm is adopted, which …


Computer Aided Brain Tumor Edge Extraction Using Morphological Operations, Warqaa Shaher Alazawee Dec 2015

Computer Aided Brain Tumor Edge Extraction Using Morphological Operations, Warqaa Shaher Alazawee

Masters Theses

Detecting the precise boundary of the area containing a recognized brain tumor is a complex problem and must be addressed since it applies to many medical modalities and tumor types. The objective of this thesis is to provide an efficient algorithm for detecting edges of brain tumors to help neurosurgeons identify the border of the critical area and distinguish the precise margin of the tumor from the rest of the brain tissue during the surgery. This thesis work exploits MRI brain tumor images as a tool to aid surgeons. MRI image segmentation is an essential step as a preliminary process …


Implementing A Linear Quadratic Spacecraft Attitude Control System, Daniel Kolosa Dec 2015

Implementing A Linear Quadratic Spacecraft Attitude Control System, Daniel Kolosa

Masters Theses

This thesis implements a linear quadratic attitude control system for a low-thrust spacecraft. The goal is to maintain spacecraft alignment with a time-varying thrust vector needed for trajectory change maneuvers. A linear quadratic attitude control approach is used to maintain spacecraft pointing throughout flight. This attitude control strategy uses the thrust-acceleration input obtained from a linear quadratic optimal trajectory control model that simulates the trajectory of a spacecraft in orbit maneuvers. This attitude model simulates a CubeSat, a small satellite that is equipped with a low-thrust propulsion and attitude control system. An orbit raising and a plane change scenario is …


An Integrated Framework For Cardiac Sounds Diagnosis, Zichun Tong Dec 2015

An Integrated Framework For Cardiac Sounds Diagnosis, Zichun Tong

Masters Theses

The Phonocardiogram (PCG) signal contains valuable information about the cardiac condition and is a useful tool in recognizing dysfunction and heart failure. By analyzing the PCG, early detection and diagnosis of heart diseases can be accomplished since many pathological conditions of the cardiovascular system cause murmurs or abnormal heart sounds. This thesis presents an algorithm to classify normal and abnormal heart sound signals using PCG. The proposed analysis is based on a framework composed of several statistical signal analysis techniques such as wavelet based de-noising, energy-based segmentation, Hilbert-Huang transform based feature extraction, and Support Vector Machine based classification. The MATLAB …


Modeling And Analysis Of Pca Workflow, Ewing Tiong Dec 2015

Modeling And Analysis Of Pca Workflow, Ewing Tiong

Masters Theses

Nursing shortage has been reported as a major problem faced not only by the United States but also by many other countries. One of the many interventions that has been used to curb nursing shortage is the increase in employment of Unlicensed Assistive Personnels (UAPs) as an alternative care delivery model. There are many types of UAP and one of them are Patient Care Assistants (PCAs). This research proposes a methodology to model and analyze the work ow of a PCA in terms of completing assigned tasks in a timely manner. The specific objectives of this research are to model …


An Investigation Of Cooling Configurations In Gas Turbine Engines Using Jet Impingement, Bhushan Upalkar Dec 2015

An Investigation Of Cooling Configurations In Gas Turbine Engines Using Jet Impingement, Bhushan Upalkar

Doctoral Dissertations and Master's Theses

A numerical investigation for predicting the heat transfer effects of turbulence was conducted by making a scaled-up model of a section in a jet impingement channel. Different turbulence models were run and the results were compared to experimental data. Experimental comparisons were made for impingement channels between a baseline case, which is a rectangular array of jets of 20 rows and 3 jets per row, and different hole spacing configurations. The heat transfer was measured using Temperature Sensitive Paint. The turbulence model v²-f gave the most accurate prediction with an error of about 17% with the EB k-E, with an …


A Proposed Integrated Data Collection, Analysis And Sharing Platform For Impact Evaluation, Andreas Kipt, Waylon Brunette, Jordon Kellerstrass, Matthew Podolsky, Javier Rosa, Mitchell Sundt, Daniel Wilson, Gaetano Borriello, Eric Brewer, Evan A. Thomas Dec 2015

A Proposed Integrated Data Collection, Analysis And Sharing Platform For Impact Evaluation, Andreas Kipt, Waylon Brunette, Jordon Kellerstrass, Matthew Podolsky, Javier Rosa, Mitchell Sundt, Daniel Wilson, Gaetano Borriello, Eric Brewer, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

Global poverty reduction efforts value monitoring and evaluation, but often struggle to translate lessons learned from one intervention into practical application in another intervention. Commonly, data is not easily or often shared between interventions and summary data collected as part of an impact evaluation is often not available until after the intervention is complete. Equally limiting, the workflows that lead to research results are rarely published in a reproducible, reusable, and easy-to-understand fashion for others. Information and communication technologies widely used in commercial and government pro- grams are growing in relevance for international global development professionals and offer a potential …


Comparative Estimates Of Anthropogenic Heat Emission In Relation To Surface Energy Balance Of A Subtropical Urban Neighborhood, Changhyoun Park, Gunnar W. Schade, Nicholas D. Werner, David J. Sailor, Cheolhee Kim Dec 2015

Comparative Estimates Of Anthropogenic Heat Emission In Relation To Surface Energy Balance Of A Subtropical Urban Neighborhood, Changhyoun Park, Gunnar W. Schade, Nicholas D. Werner, David J. Sailor, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

Long-term eddy covariance measurements have been conducted in a subtropical urban area, an older neighborhood north of downtown Houston. The measured net radiation (Q*), sensible heat flux (H) and latent heat flux (LE) showed typical seasonal diurnal variations in urban areas: highest in summer; lowest in winter. From an analysis of a subset of the first two years of measurements, we find that approximately 42% of Q* is converted into H, and 22% into LE during daytime. The local anthropogenic heat emissions were estimated conventionally using the long-term residual method and the heat emission inventory approach. We also …


Biochar From Pyrolysis Of Biosolids For Nutrient Adsorption And Turfgrass Cultivation, Daniel Elliott Carey, Patrick J. Mcnamara, Daniel Zitomer Dec 2015

Biochar From Pyrolysis Of Biosolids For Nutrient Adsorption And Turfgrass Cultivation, Daniel Elliott Carey, Patrick J. Mcnamara, Daniel Zitomer

Civil and Environmental Engineering Faculty Research and Publications

At water resource recovery facilities, nutrient removal is often required and energy recovery is an ever-increasing goal. Pyrolysis may be a sustainable process for handling wastewater biosolids because energy can be recovered in the py-gas and py-oil. Additionally, the biochar produced has value as a soil conditioner. The objective of this work was to determine if biochar could be used to adsorb ammonia from biosolids filtrate and subsequently be applied as a soil conditioner to improve grass growth. The maximum carrying capacity of base modified biochar for NH3−N was 5.3 mg/g. Biochar containing adsorbed ammonium and potassium was …


Increased Lower Limb Spasticity But Not Strength Or Function Following A Single-Dose Serotonin Reuptake Inhibitor In Chronic Stroke, Krishnaj Gourab, Brian D. Schmit, T. George Hornby Dec 2015

Increased Lower Limb Spasticity But Not Strength Or Function Following A Single-Dose Serotonin Reuptake Inhibitor In Chronic Stroke, Krishnaj Gourab, Brian D. Schmit, T. George Hornby

Biomedical Engineering Faculty Research and Publications

Objective: To investigate the effects of single doses of a selective serotonin reuptake inhibitor (SSRI) on lower limb voluntary and reflex function in individuals with chronic stroke.

Design: Double-blind, randomized, placebo-controlled crossover trial.

Setting: Outpatient research setting.

Participants: Individuals (N=10; 7 men; mean age ± SD, 57±10y) with poststroke hemiplegia of >1 year duration who completed all assessments.

Interventions: Patients were assessed before and 5 hours after single-dose, overencapsulated 10-mg doses of escitalopram (SSRI) or placebo, with 1 week between conditions.

Main Outcome Measures: Primary assessments included maximal ankle and knee isometric strength, and velocity-dependent (30°/s–120°/s) plantarflexor stretch reflexes under …


Retinal Architecture In ​Rgs9- And ​R9ap-Associated Retinal Dysfunction (Bradyopsia), Rupert W. Strauss, Adam M. Dubis, Robert F. Cooper, Rola Ba-Abbad, Anthony T. Moore, Andrew R. Webster, Alfredo Dubra, Joseph Carroll, Michel Michaelides Dec 2015

Retinal Architecture In ​Rgs9- And ​R9ap-Associated Retinal Dysfunction (Bradyopsia), Rupert W. Strauss, Adam M. Dubis, Robert F. Cooper, Rola Ba-Abbad, Anthony T. Moore, Andrew R. Webster, Alfredo Dubra, Joseph Carroll, Michel Michaelides

Biomedical Engineering Faculty Research and Publications

Purpose

To characterize photoreceptor structure and mosaic integrity in subjects with RGS9- and R9AP-associated retinal dysfunction (bradyopsia) and compare to previous observations in other cone dysfunction disorders such as oligocone trichromacy.

Design

Observational case series.

Methods

setting: Moorfields Eye Hospital (United Kingdom) and Medical College Wisconsin (USA). study population: Six eyes of 3 subjects with disease-causing variants in RGS9 or R9AP. main outcome measures: Detailed retinal imaging using spectral-domain optical coherence tomography and confocal adaptive-optics scanning light ophthalmoscopy.

Results

Cone density at 100 μm from foveal center ranged from 123 132 cones/mm2to 140 013 cones/mm2 …


Voxel-Level Absorbed Dose Calculations With A Deterministic Grid-Based Boltzmann Solver For Nuclear Medicine And The Clinical Value Of Voxel-Level Calculations, Justin Mikell Dec 2015

Voxel-Level Absorbed Dose Calculations With A Deterministic Grid-Based Boltzmann Solver For Nuclear Medicine And The Clinical Value Of Voxel-Level Calculations, Justin Mikell

Dissertations and Theses (Open Access)

Voxel-level absorbed dose (VLAD) is rarely calculated for nuclear medicine (NM) procedures involving unsealed sources or 90Y microspheres (YM). The current standard of practice for absorbed dose calculations in NM utilizes MIRD S-values, which 1) assume a uniform distribution in organs, 2) do not use patient specific geometry, and 3) lack a tumor model. VLADs overcome these limitations. One reason VLADs are not routinely performed is the difficulty in obtaining accurate absorbed doses in a clinically acceptable time. The deterministic grid-based Boltzmann solver (GBBS) was recently applied to radiation oncology where it was reported as fast and accurate for both …


An Automated Tool For High Resolution Visualization Applied To Transient Watershed Models, Noah Robert Taylor Dec 2015

An Automated Tool For High Resolution Visualization Applied To Transient Watershed Models, Noah Robert Taylor

Theses and Dissertations

Numeric hydrologic models can aid in water resource management by providing predictive simulations of water behavior. As computers become more advanced, the models developed also become more complex using more data to represent larger areas for forecasting hydrologic behavior. Unfortunately, as the simulations use more data, the output often becomes difficult to manage and share without investing time and effort into setting up server environments or decreasing the quality of the output to compensate for an efficient and effective user experience. A proposed solution to facilitate the accessibility of massive hydrologic model output is through the web-based visualization tool developed …


Configuration Scrubbing Architectures For High-Reliability Fpga Systems, Aaron Gerald Stoddard Dec 2015

Configuration Scrubbing Architectures For High-Reliability Fpga Systems, Aaron Gerald Stoddard

Theses and Dissertations

Field Programmable Gate Arrays (FPGAs) are being used more frequently in space applications because of their reconfigurability and intensive processing capabilities. FPGAs in environments like space are susceptible to ionizing radiation which can cause Single Event Upsets (SEUs) in the FPGA's configuration memory. These upsets may cause the programmed user design on the FPGA to deviate from its normal behavior. Space missions cannot afford to allow important data processing applications to become corrupted due to these radiation upsets.Configuration scrubbing is an upset mitigation technique that detects and corrects upsets in an FPGA's configuration memory. Configuration scrubbing periodically monitors an FPGA's …


Evaluating Long-Term Land Cover Changes For Malheur Lake, Oregon Using Envi And Arcgis, Ryan Joseph Woods Dec 2015

Evaluating Long-Term Land Cover Changes For Malheur Lake, Oregon Using Envi And Arcgis, Ryan Joseph Woods

Theses and Dissertations

Land cover change over time can be a useful indicator of variations in a watershed, such as the patterns of drought in an area. I present a case study using remotely sensed images from Landsat satellites for over a 30-year period to generate classifications representing land cover categories, which I use to quantify land cover change in the watershed areas that contribute to Malheur, Mud, and Harney Lakes. I selected images, about every 4 to 6 years from late June to late July, in an attempt to capture the peak vegetation growth and to avoid cloud cover. Complete coverage of …


Shaking Table Testing To Evaluate Effectiveness Of Prefabricated Vertical Drains For Liquefaction Mitigation, Caleb Robert Oakes Dec 2015

Shaking Table Testing To Evaluate Effectiveness Of Prefabricated Vertical Drains For Liquefaction Mitigation, Caleb Robert Oakes

Theses and Dissertations

This study was designed to evaluate the ability of vertical drains to prevent liquefaction and limit associated settlement. Drain performance was investigated using full-scale tests with vertical drains in liquefiable sand using a laminar shear box with acceleration time histories applied at the base. Performance of the sand box with drains in these tests was compared with performance of the sane box without drains in previous tests. The test data was also used to create case histories which can be used for further research and calibration of computer models. Although some investigations regarding vertical drains have been performed with centrifuge …


Numerical Analysis Of Passive Force On Skewed Bridge Abutments, Zifan Guo Dec 2015

Numerical Analysis Of Passive Force On Skewed Bridge Abutments, Zifan Guo

Theses and Dissertations

Accounting for seismic forces and thermal expansion in bridge design requires an accurate passive force-deflection relationship for the abutment wall. Current design codes make no allowance for skew effects on passive force; however, large scale field tests indicate that there is a substantial reduction in peak passive force as skew angle increases. A reduction in passive force also reduces the transverse shear resistance on the abutment. The purpose of this study is to validate three-dimensional model using PLAXIS 3D, against large scale test results performed at Brigham Young University and to develop a set of calibrated finite element models. The …


Design For Reduction Of Noise Produced By Natural Gas Regulator, Britany L. Chamberlain Dec 2015

Design For Reduction Of Noise Produced By Natural Gas Regulator, Britany L. Chamberlain

Undergraduate Honors Capstone Projects

This document describes the design of a multi-stage restrictive orifice device (MSRO) that serves to reduce the noise produced by a regulator valve. The scope of this document explains the determination of the proper design through the development of analytical models, the design of a test fixture to obtain empirical data, and the corroboration of the models with empirical data to obtain a working solution.


The Performance Of Quaternary Amplitude Modulation With Quaternary Spreading In The Presence Of Interfering Signals, Allison Manhard Dec 2015

The Performance Of Quaternary Amplitude Modulation With Quaternary Spreading In The Presence Of Interfering Signals, Allison Manhard

All Theses

Multiple-access digital communications is considered with direct-sequence spread-spectrum (DS-SS) quadrature amplitude modulation and quaternary spreading in each transmission. Each transmitted signal undergoes attenuation and a delay at a receiver in the additive white Gaussian noise channel. The receiver uses coherent demodulation with a correlation detector synchronized to the one of the K received signals so that the K - 1 other transmissions act as interference. The average probability of error at the output of the detector is determined using Monte Carlo simulation and compared with an approximation in which the interference component in each detection statistic is approximated by a …


Control Of Thermoforming Process Parameters To Manufacture Surfaces With Pin-Based Tooling, Vijay Sarthy Mysore Sreedhara Dec 2015

Control Of Thermoforming Process Parameters To Manufacture Surfaces With Pin-Based Tooling, Vijay Sarthy Mysore Sreedhara

All Theses

Many manufacturing processes used to mass produce parts rely on expensive and time consuming tooling. These processes include sheet metal forming, injection molding, casting, and thermoforming. The time invested in design and development of tooling can be justified for high-production volumes. However, for low-volume production and customized products, the tooling investment cannot be amortized. Flexible tooling has been developed to address the needs of smaller production volumes. Reconfigurable pin tooling is an example of flexible tooling that relies on a matrix of adjustable-height pins to produce approximate surfaces. A key challenge in pin-based tooling is achieving accurate high quality surfaces …


Detecting Occlusions Of Automobile Parts Being Inspected By A Camera System During Manufacturing Assembly, Jayadevan Puthumanappilly Dec 2015

Detecting Occlusions Of Automobile Parts Being Inspected By A Camera System During Manufacturing Assembly, Jayadevan Puthumanappilly

All Theses

This thesis considers the problem of detecting occlusions in automobile parts on a moving assembly line in an automotive manufacturing plant. This work builds on the existing ``Visual Inspector'' (VI) system developed as a joint research project between Clemson University and the BMW Spartanburg manufacturing plant. The goal is to develop a method that can successfully detect occlusions in real-time. VI is a detector and classifier system that uses video cameras to determine the correct installation of a part in the assembly line. In the current version of VI, an occluded part is flagged simply as `not OK' - as …


Structural Optimization Using Parametric Programming Method, Krupakaran Ravichandraan Dec 2015

Structural Optimization Using Parametric Programming Method, Krupakaran Ravichandraan

All Theses

The Parametric Programming method is investigated to consider its applicability to structural optimization problems. It is used to solve optimization problems that have design variables as implicit functions of some independent input parameter(s). It provides optimal solutions as a parametric function of the input parameter(s) for the entire parameter space of interest. It does not require the detailed discrete optimizations needed at a large number of parameter values as in traditional non-parametric optimization. Parametric programming is widely used in optimal controls, model predictive control, scheduling, process synthesis and material design under uncertainty due to the above mentioned benefits. Its benefits …


Single Particle And Biological Cell Detection By A Radio Frequency Interferometer, Zheng Wang Dec 2015

Single Particle And Biological Cell Detection By A Radio Frequency Interferometer, Zheng Wang

All Theses

This thesis presents a series of studies on single particle and biological cell detection and differentiation by a radio frequency (RF) interferometer system. Several techniques, such as dielectrophoresis (DEP), time domain method and 3D focusing have been illustrated and investigated to demonstrate the capacity of interrogating the electric property of single particle or biological cell by the RF interferometer. Silica particles and live yeast cells are trapped at the sensing area by DEP force and detected by the RF sensor. Solutions of particle mixtures (~4 μm silica and ~10 μm polystyrene) and cell mixtures (viable and non-viable yeast cells, normal …


Design Of A Web Application To Improve The Efficiency Of Crnas., Venkatramanan Chanchapalli Madhavan Dec 2015

Design Of A Web Application To Improve The Efficiency Of Crnas., Venkatramanan Chanchapalli Madhavan

All Theses

Physical artifacts such as whiteboards have been successfully used in healthcare facilities to keep track of dynamic changes in information and to manage work schedules. Since these whiteboards are easy- to- use and do not require any technical expertise, they have been easy- to-adopt. Additionally, they act as memory aids for the users by capturing transient information. However, they have their own limitations, the primary ones being the lack of mobility and real-time updates, both of which are crucial in a high consequence environment such as a healthcare facility. These whiteboards are usually kept in a central location with the …


Review Of Aviation Research: A Content Analysis Of Articles Published In The Collegiate Aviation Review, 2007–2012, Safak Aktemur Dec 2015

Review Of Aviation Research: A Content Analysis Of Articles Published In The Collegiate Aviation Review, 2007–2012, Safak Aktemur

Theses and Dissertations

The purpose of the study was to conduct a content analysis of the methodological quality of articles published in the Collegiate Aviation Review (CAR)” a refereed journal of the University Aviation Alliance (UAA)”to determine if actual practices of aviation researchers were consistent with commonly recommended research methods and procedures. The accessible population consisted of the 76 articles published in CAR between 2007 and 2012 (Volumes 25“30). The sample consisted of N = 69 articles and excluded literature reviews, meta-analyses, studies that described the development or validation of an instrument, philosophical inquiries, position papers, or historical studies. The analysis focused on …


Long-Term Winter Inversion Properties In A Mountain Valley Of The Western United States And Implications On Air Quality, Shih-Yu (Simon) Wang, Lawrence E. Hipps, Oi-Yu Chung, Robert R. Gillies, Randy S. Martin Dec 2015

Long-Term Winter Inversion Properties In A Mountain Valley Of The Western United States And Implications On Air Quality, Shih-Yu (Simon) Wang, Lawrence E. Hipps, Oi-Yu Chung, Robert R. Gillies, Randy S. Martin

Civil and Environmental Engineering Faculty Publications

Because of the geography of a narrow valley and surrounding tall mountains, Cache Valley (located in northern Utah and southern Idaho) experiences frequent shallow temperature inversions that are both intense and persistent. Such temperature inversions have resulted in the worst air quality in the nation. In this paper, the historical properties of Cache Valley’s winter inversions are examined by using two meteorological stations with a difference in elevation of approximately 100 m and a horizontal distance apart of ~4.5 km. Differences in daily maximum air temperature between two stations were used to define the frequency and intensity of inversions. Despite …