Environmental Design Commons^™

Remotely Testing Whether A Climate Control System Controller Is Correctly Installed, Fadi M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

Disclosed are exemplary embodiments of apparatus and methods for remote testing of controllers such as thermostats, to detect incorrect climate control system configuration parameters . In an exemplary embodiment, a computer wirelessly connects with a remote thermostat and sends signal (s) to the thermostat instructing the thermostat to perform climate control function (s) in predefined sequence (s). The computer receives signal (s) from the thermostat indicating whether the thermostat is performing the climate control function (s) in accordance with the sent signal (s). Based on the signal (s) received from the thermostat, the computer determines whether the thermostat is configured …

Need For Aeromedical Evacuation High-Level Containment Transport Guidelines, Shawn G. Gibbs, Jocelyn J. Herstein, Aurora B. Le, Elizabeth L. Beam, Theodore J. Cieslak, James V. Lawler, Joshua L. Santarpia, Terry L. Stentz, Kelli R. Kopocis-Herstein, Chandran Achutan, Gary W. Carter, John J. Lowe

Durham School of Architectural Engineering and Construction: Faculty Publications

Circumstances exist that call for the aeromedical evacuation high-level containment transport (AE-HLCT) of patients with highly hazardous communicable diseases. A small number of organizations maintain AE-HLCT capabilities, and little is publicly available regarding the practices. The time is ripe for the development of standards and consensus guidelines involving AE-HLCT.

Hvac System Remote Monitoring And Diagnosis, Jeffrey N. Arensmeier, Gregg M. Hemmelgarn, Fadi M. Alsaleem, Priotomo Abiprojo

Durham School of Architectural Engineering and Construction: Faculty Publications

A monitoring system for an HVAC system of a building includes a monitoring server located remotely from the building. The monitoring server receives, from a device installed at the building, (i) time-domain current data based on a measured aggregate current supplied to a plurality of components of the HVAC system, and (ii) data based on frequency-domain current data of the measured aggregate current. Based on the received data, the monitoring server accesses (i) whether a failure has occurred in a first com ponent of the plurality of components and (ii) generates a preliminary advisory in response to determining that the …

Strategies And Resources For Government Agencies To Utilize Disadvantaged Business Enterprises In Transportation Design-Build Projects, Baabak Ashuri, Adjo Amekudzi-Kennedy, Stephanie Amoaning-Yankson, Yunping Liang, Yang Cao

Durham School of Architectural Engineering and Construction: Faculty Publications

The Disadvantaged Business Enterprise (DBE) Program was established to provide opportunities for businesses owned and controlled by socially and economically disadvantaged individuals, such as minority-owned and women-owned businesses, to participate in federally funded transportation-related projects. Such DBE participation has increasingly been achieved over the years with the appropriate guidance for traditional project delivery: design-bid-build. However, in recent times the onset of alternative project delivery methods, such as design-build (DB), has introduced challenges for state DOTs trying to implement the DBE program using traditional approaches. This paper presents a synthesis of strategies and resources being used in state DOTs to achieve …

Skip This Chore: Cleaning Your Air Conditioner Condenser Probably Won't Make It Work Better, David Yuill

Durham School of Architectural Engineering and Construction: Faculty Publications

I asked my neighbor who hoses off his air conditioner condenser every spring why he does it. “Because my dad always told me I had to,” he said.

Conventional wisdom like what my neighbor’s dad imparted may always seem right. But through my HVAC scholarship – the study of heating, ventilation and air-conditioning systems – I’ve learned that this particular presumption is probably wrong.

Heat Pump And Air Conditioning Grading Systems And Methods, Fadi Mohammad Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

An expectation module determines an expected average power consumption of a heat pump for a predetermined period as a function of indoor and outdoor temperatures of the building during the predetermined period. A difference module determines a power difference between an average power consumption of the heat pump during the predeter mined period and the expected average power consumption of the heat pump for the predetermined period. A grade determination module determines a grade of the heat pump for the predetermined period based on the power difference of the predetermined period. A reporting module generates a displayable report including the …

Building Envelope And Interior Grading Systems And Methods, Fadi Mohammad Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A difference module determines differences between an outdoor ambient temperature and an indoor temperature, determines a first average of the differences , and determines a second average of the differences. A storing module stores a first data point, the first data point including the first average and a first total run time of a heating, ventilation, and/or air conditioning (HVAC) system, and stores a second data point, the second data point including the second average and a second total run time of the HVAC system. A fitting module fits a line to the first and second data points. An envelope …

Experiencing Extreme Height For The First Time: The Influence Of Height, Self-Judgment Of Fear And A Moving Structural Beam On The Heart Rate And Postural Sway During The Quiet Stance, Mahmoud Habibnezhad, Jay Puckett, M. S. Fardhosseini, Houtan Jebelli, Terry Stentz, L. A. Pratama

Durham School of Architectural Engineering and Construction: Faculty Publications

Falling from elevated surfaces is the main cause of death and injury at construction sites. Based on the Bureau of Labor Statistics (BLS) reports, an average of nearly three workers per day suffer fatal injuries from falling. Studies show that postural instability is the foremost cause of this disproportional falling rate. To study what affects the postural stability of construction workers, we conducted a series of experiments in the virtual reality (VR). Twelve healthy adults—all students at the University of Nebraska-Lincoln—were recruited for this study. During each trial, participants’ heart rates and postural sways were measured as the dependent factors. …

Prediction Of Stress Increase At Ultimate In Unbonded Tendons Using Sparse Principal Component Analysis, Eric Mckinney, Minwoo Chang, Marc Maguire, Yan Sun

Durham School of Architectural Engineering and Construction: Faculty Publications

While internal and external unbonded tendons are widely utilized in concrete structures, an analytical solution for the increase in unbonded tendon stress at ultimate strength, ∆f_ps, is challenging due to the lack of bond between strand and concrete. Moreover, most analysis methods do not provide high correlation due to the limited available test data. The aim of this paper is to use advanced statistical techniques to develop a solution to the unbonded strand stress increase problem, which phenomenological models by themselves have done poorly. In this paper, Principal Component Analysis (PCA), and Sparse Principal Component Analysis (SPCA) …

A Practitioner’S Guide To Small Unmanned Aerial Systems For Bridge Inspection, Sattar Dorafshan, Robert J. Thomas, Calvin Coopmans, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Small unmanned aerial system(s) (sUAS) are rapidly emerging as a practical means of performing bridge inspections. Under the right condition, sUAS assisted inspections can be safer, faster, and less costly than manned inspections. Many Departments of Transportation in the United States are in the early stages of adopting this emerging technology. However, definitive guidelines for the selection of equipment for various types of bridge inspections or for the possible challenges during sUAS assisted inspections are absent. Given the large investments of time and capital associated with deploying a sUAS assisted bridge inspection program, a synthesis of authors experiences will be …

Hvac System Air Filter Diagnostics And Monitoring, Priotomo Abiprojo, Fadi M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A system and method for monitoring a heating, ventilation, or air conditioning (HVAC) system of a building is provided. A monitoring server, located remotely from the building, receives operating parameter data from a monitoring device at the building that measures an operating parameter of the HVAC system. The monitoring server generates a plurality of data clusters from the operating parameter data, each data cluster corresponding to operating parameter data generated during steady-state operation of the HVAC system. The monitoring server calculates an average operating parameter value for each data cluster. The monitoring server calculates normalized operating parameter values based on …

Social Media Communication By Local Governments And Its Implications For Urban Planning, Leiming Zhao

Community and Regional Planning Program: Theses

Social media has altered traditional communication and enriched traditional social networks. In addition to its use for personal communication and business marketing, social media has also been proved to be a valuable tool for urban planners and managers. However, there are relatively few studies about how social media communication may inform the design of urban master plans. The objectives of the thesis are to understand how the city governments have used social media to engage with the general public on urban planning issues, and assess if social media contents can be used to inform urban planning. The 10 top digital …

Measuring Landscape Performance: Case Study Investigation, Hannah Michelle Lopresto, Brandon Zambrano, Catherine De Almeida

UCARE: Research Products

Participating in the Landscape Architecture Foundation’s 2018 Case Study Investigation has been an incredibly informative experience for our research team at the University of Nebraska-Lincoln. We are eager to shine a spotlight on the landscape performance of two Great Plains projects: P Street Corridor, a revitalized downtown streetscape in Lincoln, Nebraska, and Tom Hanafan River’s Edge Park, a waterfront redevelopment in Council Bluffs, Iowa. Working on the post-occupancy study of both projects has been extremely beneficial in understanding how reclaiming underutilized sites can create high-performing landscapes. Both are public projects in urban settings with primary goals of transforming formerly unpleasant, …

Seventy-Five North Developments: A Holistic Approach To Improving Northeast Omaha, Fabiola Alikpokou

Community and Regional Planning Program: Theses

The concentration of public housing in high-poverty neighborhoods has many negative impacts; it limits educational opportunities for kids, leads to increased crime, causes poor health outcomes, hinders wealth building, and decreases investments (U.S. Department of Housing and Urban Development, 2013). Northeast Omaha exhibits many of these issues. North Omaha is not only home to many of the city's minority persons, but also home to one of the most impoverished Black communities in the United States (Cordes, Gonzalez, & Grace, 2011). The Omaha-Council Bluffs area was ranked 14 for the highest African-American poverty rate out of 100 most populous metro areas …

A Spatiotemporal Analysis To Identify Naturally Occurring Retirement Communities In Nebraska, Sangho Lee

Community and Regional Planning Program: Theses

This study aims to identify the geographic locations of “naturally occurring retirement communities (NORCs)” and whether there were spatiotemporal patterns of naturally occurring retirement communities in Nebraska for the time periods of 2000 to 2010, and to 2015. As the American population continues to age, older people generally prefer to live in their own homes for later years of life, instead of moving into assisted living. These demands have resulted in the increase of elderly populations who are “aging in place”. Nevertheless, there have been few spatiotemporal analyses about the distribution patterns of elderly households in terms of NORCs for …

Development Of A Model To Predict The Likelihood Of Complaints Due To Assorted Tone-In-Noise Combinations, Joonhee Lee, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper develops a model to predict if listeners would be likely to complain due to annoyance when exposed to a certain noise signal with a prominent tone, such as those commonly produced by heating, ventilation, and air-conditioning systems. Twenty participants completed digit span tasks while exposed in a controlled lab to noise signals with differing levels of tones, ranging from 125 to 1000 Hz, and overall loudness. After completing the digit span tasks under each noise signal, from which task accuracy and speed of completion were captured, subjects were asked to rate level of annoyance and indicate the likelihood …

Respirable Dust Monitoring In Construction Sites And Visualization In Building Information Modeling Using Real-Time Sensor Data, Nour Smaoui, Kyungki Kim, Omprakash Gnawali, Young-Joo Lee, Wonho Suh

Durham School of Architectural Engineering and Construction: Faculty Publications

Construction activities, involving cutting, drilling, and grinding of materials, often produce toxic respirable dust that can cause fatal diseases and illnesses. To protect workers from breathing excessive amounts of respirable dust at job sites, superintendents should continuously monitor the level of respirable dust in workspaces and make timely interventions for overexposed workers. However, current practices of respirable dust monitoring have critical drawbacks, and superintendents cannot accurately estimate workers’ exposures to respirable dust or make prompt decisions to protect the workers. Therefore, there is a need for real-time air dust monitoring that can be deployed ubiquitously at a construction site and …

Analyses Of Crowd-Sourced Sound Levels Of Restaurants And Bars In New York City, Gregory S. Farber, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

For several decades, there has been a significant need to better educate the public about noise pollution. A small number of small-scale studies have focused on the sound levels of restaurants and their impact on health and hearing. There have also been an increasing number of media articles stating that eating and drinking venues are getting increasingly loud making it more difficult for people to connect with others in conversation. This study reports on an exploratory large-scale noise survey of sound levels of 2,376 restaurants and bars in New York City using a novel smart-phone application and categorized them based …

Assessing Hazard Vulnerability, Habitat Conservation, And Restoration For The Enhancement Ofmainland China’S Coastal Resilience, Muhammad Sajjad, Yangfan Li, Zhenghong Tang, Ling Cao, Xiaoping Liu

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

Worldwide, humans are facing high risks from natural hazards, especially in coastal regions with high population densities. Rising sea levels due to global warming are making coastal communities’ infrastructure vulnerable to natural disasters. The present study aims to provide a coupling approach of vulnerability and resilience through restoration and conservation of lost or degraded coastal natural habitats to reclamation under different climate change scenarios. The integrated valuation of ecosystems and tradeoffs model is used to assess the current and future vulnerability of coastal communities. The model employed is based on seven different biogeophysical variables to calculate a natural hazard index …

Numerical Simulation Of Fault Impacts For Commercial Walk-In Freezers, Alireza Behfar, David P. Yuill

Durham School of Architectural Engineering and Construction: Faculty Publications

Refrigeration systems can undergo many faults that could negatively affect their operation and performance. This paper describes a modeling process to simulate the fault impacts on the operation of a commercial walk-in freezer using semi-empirical models. These models often require less modeling effort than full forward models and could be used in scenarios where detailed information is missing, such as in field-measured systems. An important characteristic of a typical walk-in refrigeration system is the existence of a liquid-line receiver after the condenser, which significantly changes the behavior of the cycle, in comparison to a receiver-less system. Component models described in …

Simultaneous Electrical And Mechanical Resonance Drive For Large Signal Amplification Of Micro Resonators, M. H. Hasan, Fadi M. Alsaleem, N. Jaber, M. A. A. Hafiz, M. I. Younis

Durham School of Architectural Engineering and Construction: Faculty Publications

Achieving large signal-noise ratio using low levels of excitation signal is key requirement for practical applications of micro and nano electromechanical resonators. In this work, we introduce the double electromechanical resonance drive concept to achieve an order-of-magnitude dynamic signal amplification in micro resonators. The concept relies on simultaneously activating the micro-resonator mechanical and electrical resonance frequencies. We report an input voltage amplification up to 15 times for a micro-resonator when its electrical resonance is tuned to match the mechanical resonance that leads to dynamic signal amplification in air (Quality factor enhancement). Furthermore, using a multi-frequency excitation technique, input voltage and …

Impact Of Owners’ Early Decisions On Project Performance And Dispute Occurrence In Public Highway Projects, Sogand Hasanzadeh, Behzad Esmaeili, Ghada M. Gad, Douglas D. Gransberg

Durham School of Architectural Engineering and Construction: Faculty Publications

Disputes are common in the construction industry and lead to unnecessary cost and schedule overruns in projects. It is commonly believed that owners’ early decisions regarding the selection of delivery methods, procurement methods, and contract types impact the frequency and severity of project disputes; however, no previous study has empirically tested this hypothesis, particularly in highway public projects. Therefore, this study empirically investigated the impact of owners’ early decisions regarding project organization (i.e., delivery methods, procurement, and contract types) on performance measures (e.g., cost and schedule growth), specifically dispute performance metrics (e.g., frequency and severity of disputes), in public highway …

Method For Radon Measurement In Residential Sewer Connections, David Yuill

Durham School of Architectural Engineering and Construction: Faculty Publications

Radon gas is the most deadly indoor air pollutant. In the US, it is responsible for over 20,000 deaths per year. Residential exposure is typically the largest portion of a person’s annual exposure, so a great deal of research has been done to understand the pathways that radon can follow to enter a house. Since radon emanates from the ground, it is present in high concentration in soil gas. Recent research on the vapor intrusion of volatile organic compounds from subsurface sources into a test house concluded that the sewer line is an important preferential pathway. Despite the potential for …

Utilizing Wearable Devices To Design Personal Thermal Comfort Model, Mostafa Rafaie, Mehari Tesfay, Fadi Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

have confirmed that thermal comfort significantly depends on internal personal parameters such as metabolic rate, age, and health status. This is manifested as a difference in comfort levels between people residing under the same roof, and hence no general comprehensive comfort model satisfying everyone. Current and newly emerging advancements in state of the art wearable technology have made it possible to continuously acquired biometric information. This work proposes to access and exploit this data to build personal thermal comfort model. Relying on various supervised machine-learning methods, a personal thermal comfort model will be produced and compared to a general model …

Localized Indoor Temperature Estimation Using Smartphone And Laptop Internal Sensors, Mostafa Rafaie, Mehari Tesfay, Fadi Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper investigates a mechanism in which indoor air temperature can be predicted using the temperature sensor on the battery and the CPU of smartphones or laptops, where data is easily accessible and ubiquitous. As a case study, several machine-learning methods were used to build models from a laptop data and the measured surrounding air temperature. The effects of the machine learning type and input feature size (by including other parameters such as CPU processing usage and battery charge percentage) on the model accuracy were investigated. The goal is to determine a set of feature combinations that can be used …

Comfort-Based Optimal Temperature Setpoint Calculation, Andrew Holthaus, Mostafa Rafaie, Fadi Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

General practice in current building HVAC control is to select building temperature setpoints that comply with ASHRAE Standard 55. By meeting this standard, based on the PMV comfort model, 80% of building occupants should be satisfied with their thermal environment. However, unfortunately, this is rarely the case. One possible reason for this is the variation in occupant activity and clothing that are usually assumed default values using this standard. In this work, we present an iterative-based algorithm to solve this problem. The algorithm solves the PMV inverse model equation to determine the optimal temperature setpoint while inferring human activity level …

Sdnet2018: An Annotated Image Data Set For Non-Contact Concrete Crack Detection Using Deep Convolutional Neural Networks, Sattar Dorafshan, Robert J. Thomas, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

SDNET2018 is an annotated image data set for training, validation, and benchmarking of artificial intelligence based crack detection algorithms for concrete. SDNET2018 contains over 56,000 images of cracked and non-cracked concrete bridge decks, walls, and pavements. The dataset includes cracks as narrow as 0.06 mm and as wide as 25 mm. The data set also includes images with a variety of obstructions, including shadows, surface roughness, scaling, edges, holes, and background debris. SDNET2018 will be useful for the continued development of concrete crack detection algorithms based on deep convolutional neural networks (DCNNs), which are a subject of continued research in …

Evaluation The Effect Of Washing On The Heat Transfer Capacity And Air-Side Flow Resistance Of Air Cooled Condensers, Mehdi Mehrabi, David Yuill

Durham School of Architectural Engineering and Construction: Faculty Publications

17th International Refrigeration and Air Conditioning Conference at Purdue, July 9-12, 2018

Infrared Thermography For Weld Inspection: Feasibility And Application, Sattar Dorafshan, Marc Maguire, William Collins

Durham School of Architectural Engineering and Construction: Faculty Publications

Traditional ultrasonic testing (UT) techniques have been widely used to detect surface and sub-surface defects of welds. UT inspection is a contact method which burdens the manufacturer by storing hot specimens for inspection when the material is cool. Additionally, UT is only valid for 5 mm specimens or thicker and requires a highly skilled operator to perform the inspections and interpret the signals. Infrared thermography (IRT) has the potential to be implemented for weld inspections due to its non-contact nature. In this study, the feasibility of using IRT to overcome the limitations of UT inspection is investigated to detect inclusion, …

Hvac System Remote Monitoring And Diagnosis Of Refrigerant Line Obstruction, Fadi M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A heating, ventilation, and air conditioning (HVAC) system of a building includes a refrigerant loop. A monitoring system for the HVAC system includes a monitoring device installed at the building. The monitoring device is configured to measure a first temperature of refrigerant in a refrigerant line located between a filter - drier of the refrigerant loop and an expansion valve of the refrigerant loop. The monitoring system includes a monitoring server, located remotely from the building. The monitoring server is con figured to receive the first temperature and, in response to the first temperature being less than a threshold, generate …