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Full-Text Articles in Architecture
Development Of A Model To Predict The Likelihood Of Complaints Due To Assorted Tone-In-Noise Combinations, Joonhee Lee, Lily M. Wang
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
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
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 …
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
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
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 …
Numerical Simulation Of Fault Impacts For Commercial Walk-In Freezers, Alireza Behfar, David P. Yuill
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 …
Method For Radon Measurement In Residential Sewer Connections, David Yuill
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
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
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 …
Evaluation The Effect Of Washing On The Heat Transfer Capacity And Air-Side Flow Resistance Of Air Cooled Condensers, Mehdi Mehrabi, David Yuill
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
Comfort-Based Optimal Temperature Setpoint Calculation, Andrew Holthaus, Mostafa Rafaie, Fadi Alsaleem
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
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 …
Infrared Thermography For Weld Inspection: Feasibility And Application, Sattar Dorafshan, Marc Maguire, William Collins
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
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 …