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Full-Text Articles in Architectural Engineering

Out-Of-Plane Flexural Behavior Of Insulatedwall Panels Constructed With Large Insulation Thicknesses, Jacob Luebke, Fray F. Pozo-Lora, Salam Al-Rubaye, Marc Maguire May 2023

Out-Of-Plane Flexural Behavior Of Insulatedwall Panels Constructed With Large Insulation Thicknesses, Jacob Luebke, Fray F. Pozo-Lora, Salam Al-Rubaye, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Insulated concrete sandwich wall panels (ICSWPs) are gaining popularity as energy regulations become stricter worldwide. ICSWPs are now being constructed with thinner wythes and thicker insulation to keep up with the changing market, which is reducing material costs and increasing thermal and structural efficiency. However, there is a need for adequate experimental testing to validate the current design methods for these new panels. This research aims to provide that validation by comparing the predictions of four different methods with experimental data obtained from six large-scale panels. The study found that while current design methods adequately predict the behavior of thin …


Energy Efficient Integrated Mems Neural Network For Simultaneous Sensing And Computing, Hamed Nikfarjam, Mohammad Megdadi, Mohammad Okour, Siavash Pourkamali, F. M. Alsaleem Apr 2023

Energy Efficient Integrated Mems Neural Network For Simultaneous Sensing And Computing, Hamed Nikfarjam, Mohammad Megdadi, Mohammad Okour, Siavash Pourkamali, F. M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

Biological systems seamlessly combine multiple functions in lightweight and energy-efficient structures. Such capability in synthetic structures would be desirable in numerous engineering applications such as aerospace, robotics and wearable devices. Here we report an integrated silicon-based structure configured to sense, perform different classification algorithms, and produce an action signal within the same physical layer. The algorithms are coded in the mechanical responses of the sensing elements of multiple coupled micro-electromechanical systems (MEMS), simultaneously capturing acceleration measurements to produce an actuated signal. This all-in-one structure operates with zero circuitry and low power consumption. As a demonstration, we designed and fabricated a …


Reconfigurable Metatiles With Circular Maze-Like Space-Coiling-Based Acoustic Metastructure For Low-To-Mid Frequency Sound Attenuation, Sanjay Kumar, Heow Pueh Lee Apr 2023

Reconfigurable Metatiles With Circular Maze-Like Space-Coiling-Based Acoustic Metastructure For Low-To-Mid Frequency Sound Attenuation, Sanjay Kumar, Heow Pueh Lee

Durham School of Architectural Engineering and Construction: Faculty Publications

This study presents a compact, lightweight, and reconfigurable acoustic metatile for sound mitigation applications. The metatile prototype is designed based on a circular maze-like acoustic metastructure, which utilizes a space-coiling technique for enhanced acoustic performance in low-to-mid frequencies. The proposed labyrinthine acoustic metadisk structure comprises a central hollow front face sheet and two coiling-up backing cavities. Experimental results show that the metadisk has high absorption peaks of 0.81 and 0.75 at 574 and 1436 Hz, respectively, and exhibits high sound transmission loss (STL) values (≥25 dB) in separate wide frequency bands between 100–580 Hz and 820–1600 Hz. Based on the …


Structural Testing Of Concrete Walls On-Edge With Combined Axial And Out-Of-Plane Loading, Salam Al-Rubaye, Marc Maguire Apr 2023

Structural Testing Of Concrete Walls On-Edge With Combined Axial And Out-Of-Plane Loading, Salam Al-Rubaye, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Full-scale testing of structural components can be time consuming and difficult. The design of full- scale slender concrete walls is highly influenced and controlled by second-order and out-of-plane bending loads. Previous experiments on out-plane bending of slender walls and insulated walls have been performed with bending in the direction of gravity (with or against). Additionally, most of the research considering out-of-plane bending does not include an axial load and suffers from inaccurate results due to not simulating the actual loading and constraining conditions or safety issues. This testing method was developed expressly for the determination of slender wall behavior in …


Inter-Wythe Slip Design Criteria For Non-Composite Insulated Walls, Abdelrahman Awawdeh, Fray F. Pozo-Lora, Marc Maguire Apr 2023

Inter-Wythe Slip Design Criteria For Non-Composite Insulated Walls, Abdelrahman Awawdeh, Fray F. Pozo-Lora, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Non-composite insulated wall connector design is governed by ICC-ES AC320. This standard works entirely in the loading domain, asking the engineer to prevent connector failure due to tension and shear loading. In this paper, the authors discuss additional criteria related to thermal loading and out-of-plane wind loading that create displacement demand in the non-composite connectors. Loads suitable for such analyses are not well defined. Loads are assumed and demonstrated herein and shown to cause significant displacement demand on connectors. Limited non-composite wythe connector testing is available, and some results are presented here. A comparison indicates that outright failure of non-composite …


Relationships Between Residence Characteristics And Nursing Home Compare Database Quality Measures, Brian J. Puckett, Erica E. Ryherd, Natalie Manley, Carey S. Ryan Apr 2023

Relationships Between Residence Characteristics And Nursing Home Compare Database Quality Measures, Brian J. Puckett, Erica E. Ryherd, Natalie Manley, Carey S. Ryan

Durham School of Architectural Engineering and Construction: Faculty Publications

Objective: This study evaluated relationships between physical characteristics of nursing home residences and quality-of-care measures.

Design: This was a cross-sectional ecologic study. The dependent variables were 5 Centers for Medicare & Medicaid Services (CMS) Nursing Home Compare database long-stay quality measures (QMs) during 2019: percentage of residents who displayed depressive symptoms, percentage of residents who were physically restrained, percentage of residents who experienced 1 or more falls resulting in injury, percentage of residents who received antipsychotic medication, and percentage of residents who received anti-anxiety medication. The independent variables were 4 residence characteristics: ownership type, size, occupancy, and region …


Design Of Wythe Connectors For Concentrated Out-Of-Plane Loading Of Insulated Walls, Ammar Al-Maabreh, Fray F. Pozo, Marc Maguire Apr 2023

Design Of Wythe Connectors For Concentrated Out-Of-Plane Loading Of Insulated Walls, Ammar Al-Maabreh, Fray F. Pozo, Marc Maguire

Durham School of Architectural Engineering and Construction: Faculty Publications

Partially composite concrete insulated wall panels must be designed to handle different types of loading, including out-of-plane concentrated loads. Currently, there is a lack of information that describes and helps engineers analyze the mechanics of axial load transfer for insulated wall panels for concentrated out-of-plane loads that may occur from lifting, handling, or floor/roof reactions. Such loading generates axial and shear forces in the wythe connectors, making it important to choose the type and quantity of connectors in the design process. This paper aims to develop a better understanding of out-of-plane point load mechanics on concrete sandwich wall panels. A …


Analysis And Design Of Lateral Framing Systems For Multi-Story Steel Buildings, Husam Al Dughaishi, Jawad Al Lawati, Moad Alosta, Shaker Mahmood, Mohamed Faisal Al-Kazee, Nur Izzi Md Yusoff, Abdalrhman Milad Mar 2023

Analysis And Design Of Lateral Framing Systems For Multi-Story Steel Buildings, Husam Al Dughaishi, Jawad Al Lawati, Moad Alosta, Shaker Mahmood, Mohamed Faisal Al-Kazee, Nur Izzi Md Yusoff, Abdalrhman Milad

Durham School of Architectural Engineering and Construction: Faculty Publications

This study focused on identifying the most appropriate structural system for multi-story buildings and analyzing its response to lateral loads. The study analyzed and compared the different structural systems to determine the most suitable option. The study aims to utilize three lateral framing systems (moment, braced, and diagrid) in order to investigate which system needs the least amount of steel to meet the design requirements. Thus, in order to determine the estimated steel savings of this system as compared to the moment and braced frames, the four-story and eight-story buildings that are 96' × 96' in the plane and utilize …


Airborne Infection Risks From Covid-19 In Meat Processing Plants And Different Solutions To Mitigate The Risks, Debayan Shom Mar 2023

Airborne Infection Risks From Covid-19 In Meat Processing Plants And Different Solutions To Mitigate The Risks, Debayan Shom

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

Meat processing plants are linked to the rapid spread of COVID-19 cases. A related literature review shows a lack of proper ventilation standards for the meat processing plants for workers’ health and safety. Ventilation rates in these plants are considered adequate if the meat products are unadulterated. Thus, the air distribution and ventilation rate experiments were conducted in three meat processing plants. These measured ventilation rates were either compared to ASHRAE Std. 62.1 (2019) for a similar space or the design values provided by the plant’s administration. The measured values were low in common spaces, such as the cafeteria and …


A Framework To Predict Variability Characteristics In Building Load Profiles, Sam Moayedi, Andrew Parker, Kevin James, Xiaoyue Cheng, Michael Hempel, Hamid Sharif, Mahmoud A. Alahmad Jan 2023

A Framework To Predict Variability Characteristics In Building Load Profiles, Sam Moayedi, Andrew Parker, Kevin James, Xiaoyue Cheng, Michael Hempel, Hamid Sharif, Mahmoud A. Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

The expansion of Advanced Metering Infrastructure (AMI) has provided building operators and researchers detailed information on building energy consumption. The majority of AMI systems, however, record data at relatively low resolutions of 15, 30, or 60 minutes, due to cost, storage and bandwidth limitations. Emerging applications in power flow analysis, Quasi-Static Time-Series Simulation (QSTS), smart grid integration and load matching, however, require data at higher resolutions. Short-term energy demand can deviate significantly from long-term averages, with an unknown magnitude and frequency when only low-resolution load profile data is available. This paper presents a novel data-driven approach to predict characteristics of …


Integration Of Real-Time Semantic Building Map Updating With Adaptive Monte Carlo Localization (Amcl) For Robust Indoor Mobile Robot Localization, Matthew Peavy, Pileun Kim, Hafiz Oyediran, Kyungki Kim Jan 2023

Integration Of Real-Time Semantic Building Map Updating With Adaptive Monte Carlo Localization (Amcl) For Robust Indoor Mobile Robot Localization, Matthew Peavy, Pileun Kim, Hafiz Oyediran, Kyungki Kim

Durham School of Architectural Engineering and Construction: Faculty Publications

A robot can accurately localize itself and navigate in an indoor environment based on information about the operating environment, often called a world or a map. While typical maps describe structural layouts of buildings, the accuracy of localization is significantly affected by nonstructural building elements and common items, such as doors, appliances, and furniture. This study enhances the robustness and accuracy of indoor robot localization by dynamically updating the semantic building map with non-structural elements detected by sensors. We propose modified Adaptive Monte Carlo Localization (AMCL), integrating object recognition and map updating into the traditional probabilistic localization. With the proposed …


Dissipated Hysteretic Energy Reconstruction For High-Resolution Seismic Monitoring Of Instrumented Buildings, Milad Roochi, Eric M. Hernández, David V. Rosowsky Jan 2023

Dissipated Hysteretic Energy Reconstruction For High-Resolution Seismic Monitoring Of Instrumented Buildings, Milad Roochi, Eric M. Hernández, David V. Rosowsky

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper proposes a high-resolution seismic monitoring framework that employs dissipated energy as a feature for damage detection and localization in instrumented building structures. The the methodology consists of (1) implementing a nonlinear state observer to reconstruct the dynamic response at all degrees of freedom (DoF) of a structural model, (2) employing the reconstructed response to estimate element-by-element forces and displacements, and (3) using estimated displacement, forces, and constitutive laws to estimate elementlevel dissipated energy. The main advantages of the proposed energy-based approach are that i) the proposed feature is physically meaningful and correlates well with the level of cyclic …


Integrating Life-Cycle Analysis Into Civil Infrastructure Resilience Decision Making: Illustrative Application To Seismic Resilience Modeling Of Us Communities, Milad Roohi, Jiate Li, W. Van De Lindt Jan 2023

Integrating Life-Cycle Analysis Into Civil Infrastructure Resilience Decision Making: Illustrative Application To Seismic Resilience Modeling Of Us Communities, Milad Roohi, Jiate Li, W. Van De Lindt

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper aims to integrate life-cycle analysis into civil infrastructure resilience modeling and decision-making in seismic-prone communities. To achieve this aim, the authors present a methodology for modeling seismic life-cycle resilience of interdependent buildings and lifeline systems and subsequently informing resilience decisions directly related to the maintenance and retrofit of interdependent infrastructure to enhance a community’s physical, social, and economic systems. The methodology consists of 1) community data collection, 2) seismic hazard analysis, 3) physical damage analysis, and 4) system-level functionality and restoration analysis, 5) socio-economic impact analysis, 6) life-cycle optimization and retrofit decisionmaking. The methodology begins by developing geospatial …


Applying Unsupervised Machine Learning Clustering Techniques To Early Childcare Soundscapes, Kenton Hummel, Erica E. Ryherd, Iason Konstantzos, Abbie Raikes Dec 2022

Applying Unsupervised Machine Learning Clustering Techniques To Early Childcare Soundscapes, Kenton Hummel, Erica E. Ryherd, Iason Konstantzos, Abbie Raikes

Durham School of Architectural Engineering and Construction: Faculty Publications

Early childhood is a critical time period for language, brain, cognitive, and social/emotional development. Out-of-home childcare is a normative, typical experience for millions of young children. Although Indoor Environmental Quality (IEQ) in K-12 settings has received recent, significant attention, the links between IEQ and children’s learning and development in early childcare settings is a less understood topic. This work focuses specifically on the sound aspect of IEQ in early childcare settings to better understand typical noise levels and occupant experience. Standard approaches to analyzing background noise will be presented alongside more detailed statistical analyses utilizing unsupervised machine learning clustering techniques. …


Foreign Object Debris Detection For Airport Pavement Images Based On Self-Supervised Localization And Vision Transformer, Travis Munyer, Daniel Brinkman, Xin Zhong, Chenyu Huang, Iason Konstantzos Oct 2022

Foreign Object Debris Detection For Airport Pavement Images Based On Self-Supervised Localization And Vision Transformer, Travis Munyer, Daniel Brinkman, Xin Zhong, Chenyu Huang, Iason Konstantzos

Durham School of Architectural Engineering and Construction: Faculty Publications

Supervised object detection methods provide subpar performance when applied to Foreign Object Debris (FOD) detection because FOD could be arbitrary objects according to the Federal Aviation Administration (FAA) specification. Current supervised object detection algorithms require datasets that contain annotated examples of every to-be-detected object. While a large and expensive dataset could be developed to include common FOD examples, it is infeasible to collect all possible FOD examples in the dataset representation because of the openended nature of FOD. Limitations of the dataset could cause FOD detection systems driven by those supervised algorithms to miss certain FOD, which can become dangerous …


Zero Net Energy Test House, Timothy Hemsath, James D. Goedert, Avery Don Schwer, Yong Cho Sep 2022

Zero Net Energy Test House, Timothy Hemsath, James D. Goedert, Avery Don Schwer, Yong Cho

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper describes the first phase of a residential research program to reduce the impact of new construction on the environment through research and education using a Zero Net Energy Test House as a framework. Containing four bedrooms, three and a half baths, the 1,800 square foot house, 1,000 square foot basement, is located in Omaha, Nebraska. It is being used to validate several research projects and provides a platform for applications research of a number of technological advances. Laminated photovoltaic solar panels, a wind turbine, and an occupant monitoring energy control system are some of the sustainable design innovations …


Intelligibility Of Medically Related Sentences In Quiet, Speech-Shaped Noise, And Hospital Noise, Tessa Bent, Melissa Baese-Berk, Erica E. Ryherd, Sidney Perry May 2022

Intelligibility Of Medically Related Sentences In Quiet, Speech-Shaped Noise, And Hospital Noise, Tessa Bent, Melissa Baese-Berk, Erica E. Ryherd, Sidney Perry

Durham School of Architectural Engineering and Construction: Faculty Publications

Noise in healthcare settings, such as hospitals, often exceeds levels recommended by health organizations. Although researchers and medical professionals have raised concerns about the effect of these noise levels on spoken communication, objective measures of behavioral intelligibility in hospital noise are lacking. Further, no studies of intelligibility in hospital noise used medically relevant terminology, which may differentially impact intelligibility compared to standard terminology in speech perception research and is essential for ensuring ecological validity. Here, intelligibility was measured using online testing for 69 young adult listeners in three listening conditions (i.e., quiet, speech-shaped noise, and hospital noise: 23 listeners per …


Neuromorphic Computing Using Electrostatic Mems Devices, Fadi Alsaleem Apr 2022

Neuromorphic Computing Using Electrostatic Mems Devices, Fadi Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

A continuous - time recurrent neural network ( CTRNN ) is described that exploits the nonlinear dynamics of micro electro - mechanical system ( MEMS ) devices to model a neuron in accordance with a neuron rate model that is the basis for dynamic field theory . Each MEMS device in the CTRNN is configured to simulate a neuron population by exploiting the characteristics of bi - stability and hysteresis inherent in certain MEMS device structures . In an embodiment , the MEMS device is a microbeam or cantilevered microbeam device that is excited with an alternating current ( AC …


Ahp Based Multi Criteria Decision Analysis Of Success Factors To Enhance Decision Making In Infrastructure Construction Projects, Solomon Belay, James D. Goedert, Asregedew Woldesenbet, Saeed Rokooei Feb 2022

Ahp Based Multi Criteria Decision Analysis Of Success Factors To Enhance Decision Making In Infrastructure Construction Projects, Solomon Belay, James D. Goedert, Asregedew Woldesenbet, Saeed Rokooei

Durham School of Architectural Engineering and Construction: Faculty Publications

The study presents analytical data-based multi-criteria approach of critical success factors of infrastructure construction projects analyzed in the Ethiopian construction industry. This multi-criteria technique helps to improve the decision capabilities and ultimate performance of construction processes in various low-income countries of the East African region. The aim of this paper is to establish a logical relationship and interdependencies of success-related factors for enhancing decision making for various project teams and identify priorities while taking into account all known construction organizational constraints. A structured hierarchical matrix was developed based on a pre-identified success-related factors, and initially evaluated by experienced professionals as …


Availability Heuristic In Construction Workforce Decision-Making Amid Covid-19 Pandemic: Empirical Evidence And Mitigation Strategy, Yunping Liang, Anil Baral, Mohsen Shahandashti, Baabak Ashuri Jan 2022

Availability Heuristic In Construction Workforce Decision-Making Amid Covid-19 Pandemic: Empirical Evidence And Mitigation Strategy, Yunping Liang, Anil Baral, Mohsen Shahandashti, Baabak Ashuri

Durham School of Architectural Engineering and Construction: Faculty Publications

The decision-making situations of the construction workforce have been drastically altered since the outbreak of the Coronavirus 2019 (COVID-19) pandemic. The new situation, where decision-makers strive to promptly respond to the unprecedented crisis to sustain essential construction operations without compromising the safety and health of workers, implies the presence of an availability heuristic. An availability heuristic has the potential to bring unconscious, systematic errors to the decision-making process. This study creates a decision-making experiment to empirically examine the presence of an availability heuristic and the effectiveness of a corresponding mitigation strategy in construction workforce decision-making under COVID-19 uncertainties. The experiment …


Impact Of Covid-19 On The Diversity Of The Construction Workforce, Anil Baral, Yunping Liang, Mingshu Li, Marilyn Gonzalez, Mohsen Shahandashti, Baabak Ashuri Jan 2022

Impact Of Covid-19 On The Diversity Of The Construction Workforce, Anil Baral, Yunping Liang, Mingshu Li, Marilyn Gonzalez, Mohsen Shahandashti, Baabak Ashuri

Durham School of Architectural Engineering and Construction: Faculty Publications

Construction industry employment has been severely impacted by the coronavirus (COVID-19) pandemic. This paper examines the impact of the COVID-19 pandemic in the US construction labor market. This study contributes to the state of knowledge by (1) revealing how the COVID-19 pandemic impacted construction employment across different demographic groups and geographic regions in the US, and (2) identifying vulnerable demographic groups (e.g., minorities, women, older workers) in the construction workforce that are disproportionally impacted by the pandemic. Employment data from the Current Population Survey and Current Employment Statistics (CES) programs, which are administered by the Bureau of Labor Statistics, are …


Tilt-Up Partially Composite Insulated Wall Panels, Marc Maguire, Salam Al-Rubaye Jan 2022

Tilt-Up Partially Composite Insulated Wall Panels, Marc Maguire, Salam Al-Rubaye

Durham School of Architectural Engineering and Construction: Faculty Publications

This research project was initiated to investigate the behavior of load-bearing concrete insulated wall panels for use in tilt-up construction. The primary objective was to understand the inelastic behavior of these panels so that engineers could perform a proper second-order analysis for combined axial and out-of-plane loading. Toward this aim, the Tilt-up Concrete Institute (TCA) and wythe connector suppliers Innstruct, Thermomass, HK Composites, Dayton Superior, and IconX, funded this study.

This report contains information related to testing of solid and partially composite insulated wall panels that integrated proprietary wythe connection systems. Using the information from these tests, a method to …


Challenges And Enabling Features Of Small And Medium Infrastructure Public-Private Partnerships (P3s): A Case Study Of The Us P3 Infrastructure Market, Yunping Liang, Baabak Ashuri Jan 2022

Challenges And Enabling Features Of Small And Medium Infrastructure Public-Private Partnerships (P3s): A Case Study Of The Us P3 Infrastructure Market, Yunping Liang, Baabak Ashuri

Durham School of Architectural Engineering and Construction: Faculty Publications

Purpose: In classical perspective, projects under a certain size are not feasible for P3. However, there is an emerging trend on using P3 to deliver projects that are frequently small to medium sized to meet ever-increasingly complex social needs, including enhancing lifecycle performance of existing facilities, designing and building for resilience and sustainability, ensuring cost effectiveness of public spending, and fostering innovation. In contrast with the increasing implementation, small and medium P3s, especially those in the United States, receive little attention in existing studies. This study aims at answering the question: in the context of the US, what features of …


Higher Sound Levels In K-12 Classrooms Correlate To Lower Math Achievement Scores, Laura Caroline Brill, Lily M. Wang Nov 2021

Higher Sound Levels In K-12 Classrooms Correlate To Lower Math Achievement Scores, Laura Caroline Brill, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Sound levels from occupied classrooms have been gathered from 220 classrooms across four grade levels (3, 5, 8 and 11) over six school days each and processed with k-means clustering into speech and non-speech clusters. Three metrics describing the classroom acoustics, including the average daily A-weighted equivalent level for non-speech, the average daily difference between the A-weighted equivalent levels for speech and nonspeech (a signal to noise ratio), and the mid-frequency averaged reverberation time, were analyzed against classroom-aggregated standardized reading and math achievement test scores, while controlling for classroom demographics including socioeconomic status. Interactions between the metrics and demographics were …


Investigation Of The Prevalence Of Faults In The Heating, Ventilation, And Air-Conditioning Systems Of Commercial Buildings, Amir Ebrahimifakhar Nov 2021

Investigation Of The Prevalence Of Faults In The Heating, Ventilation, And Air-Conditioning Systems Of Commercial Buildings, Amir Ebrahimifakhar

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This dissertation describes a large-scale investigation of heating, ventilation, and air-conditioning (HVAC) fault prevalence in commercial buildings in the United States. A multi-year dataset with 36,556 pieces of HVAC equipment including air handling units (AHUs), air terminal units (ATUs), and packaged rooftop units (RTUs) was analyzed to determine values for several HVAC fault prevalence metrics. The primary source of data for this study comes from three commercial fault detection and diagnostics (FDD) providers. Since each FDD provider uses different terms to refer to the same fault in an HVAC system, a mapping function was created for each FDD provider’s dataset, …


The Effects Of The Visual Environment On K-12 Student Achievement, Michael Kuhlenengel, Iason Konstantzos, Clarence E. Waters Oct 2021

The Effects Of The Visual Environment On K-12 Student Achievement, Michael Kuhlenengel, Iason Konstantzos, Clarence E. Waters

Durham School of Architectural Engineering and Construction: Faculty Publications

The varying indoor environments among educational buildings can have an impact on students’ ability to learn. This study looks at field data from 220 classrooms in the Midwest, United States, over a two-year period, to analyze the effects of the visual environment on student achievement. The visual environmental metrics considered within this scope include the three new view metrics introduced within the EN 17037 “Daylight of Buildings” standard (Horizontal Sight Angle, Outside Distance of View, and Number of View Layers), as well as standard daylight and electric lighting metrics, focusing on light availability and glare. To capture student achievement, math …


Simulation For A Mems-Based Ctrnn Ultra-Low Power Implementation Of Human Activity Recognition, Muhammad Emad-Ud-Din, Mohammad H. Hasan, Roozbeh Jafari, Siavash Pourkamali, Fadi M. Alsaleem Sep 2021

Simulation For A Mems-Based Ctrnn Ultra-Low Power Implementation Of Human Activity Recognition, Muhammad Emad-Ud-Din, Mohammad H. Hasan, Roozbeh Jafari, Siavash Pourkamali, Fadi M. Alsaleem

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper presents an energy-efficient classification framework that performs human activity recognition (HAR). Typically, HAR classification tasks require a computational platform that includes a processor and memory along with sensors and their interfaces, all of which consume significant power. The presented framework employs microelectromechanical systems (MEMS) based Continuous Time Recurrent Neural Network (CTRNN) to performHAR tasks very efficiently. In a real physical implementation, we show that the MEMS-CTRNN nodes can perform computing while consuming power on a nano-watts scale compared to the micro-watts state-of-the-art hardware. We also confirm that this huge power reduction doesn’t come at the expense of reduced …


Framework To Develop Time- And Voltage-Dependent Building Load Profiles Using Polynomial Load Models, Andrew Parker, Mhd Anas Alkrch, Kevin James, Ahmad Almaghrebi, Mahmoud Alahmad Sep 2021

Framework To Develop Time- And Voltage-Dependent Building Load Profiles Using Polynomial Load Models, Andrew Parker, Mhd Anas Alkrch, Kevin James, Ahmad Almaghrebi, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

The power consumption of buildings over the course of each minute, hour, day and season plays a major role in how this load influences the Electric Power System voltage and frequency, and vice versa. This consumption is based on the building's load component types, efficiencies, and how they consume power and react to changes in real time. Due to this complexity, standard full-building load models are typically voltage-invariant. This paper proposes a novel framework to transform these voltage-invariant building load models into fully time- and voltage-dependent load profiles using available data on the voltage sensitivity of individual load components. While …


A Case Study To Quantify Variability In Building Load Profiles, Andrew Parker, Sam Moayedi, Kevin James, Dongming Peng, Mahmoud Alahmad Sep 2021

A Case Study To Quantify Variability In Building Load Profiles, Andrew Parker, Sam Moayedi, Kevin James, Dongming Peng, Mahmoud Alahmad

Durham School of Architectural Engineering and Construction: Faculty Publications

Recent technology development and penetration of advanced metering infrastructure (AMI), advanced building control systems, and the internet-of-things (IoT) in the built environment are providing detailed information on building operation, performance, and user's comfort and behavior. Building owners can obtain a wide range of energy consumption details at various levels of time granularity to augment their decisions as they manage the building operation and interact with the grid. AMI data are providing a new level of detail and visibility that may enhance building services and assets in the smart grid domain and make buildings inch closer to becoming a grid-interactive energy …


Evaluating Prediction Models Of Creep And Drying Shrinkage Of Self-Consolidating Concrete Containing Supplementary Cementitious Materials/Fillers, Micheal Asaad, George Morcous Aug 2021

Evaluating Prediction Models Of Creep And Drying Shrinkage Of Self-Consolidating Concrete Containing Supplementary Cementitious Materials/Fillers, Micheal Asaad, George Morcous

Durham School of Architectural Engineering and Construction: Faculty Publications

Supplementary cementitious materials (SCMs) and fillers play an important role in enhancing the mechanical properties and durability of concrete. SCMs and fillers are commonly used in self-consolidating concrete (SCC) mixtures to also enhance their rheological properties. However, these additives could have significant effects on the viscoelastic properties of concrete. Existing models for predicting creep and drying shrinkage of concrete do not consider the effect of SCM/filler on the predicted values. This study evaluates existing creep and drying shrinkage models, including AASHTO LRFD, ACI209, CEB-FIP MC90-99, B3, and GL2000, for SCC mixtures with different SCMs/fillers. Forty SCC mixtures were proportioned for …