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Lighting Energy Consumption in Ultra-Low Energy Buildings: Using a Simulation and Measurement Methodology to Model Occupant Behavior and Lighting Controls

Zhu, Panyu; Gilbride, Michael; Yan, Da; Sun, Hongshan; Meek, Christopher. (2017). Lighting Energy Consumption in Ultra-Low Energy Buildings: Using a Simulation and Measurement Methodology to Model Occupant Behavior and Lighting Controls. Building Simulation, 10(6), 799 – 810.

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Abstract

As building owners, designers, and operators aim to achieve significant reductions in overall energy consumption, understanding and evaluating the probable impacts of occupant behavior becomes a critical component of a holistic energy conservation strategy. This becomes significantly more pronounced in ultra-efficient buildings, where system loads such as heating, cooling, lighting, and ventilation are reduced or eliminated through high-performance building design and where occupant behavior-driven impacts reflect a large portion of end-use energy. Further, variation in behavior patterns can substantially impact the persistence of any performance gains. This paper describes a methodology of building occupant behavior modeling using simulation methods developed by the Building Energy Research Center (BERC) at Tsinghua University using measured energy consumption data collected by the University of Washington Integrated Design Lab (UW IDL). The Bullitt Center, a six-story 4831 m(2) (52,000 ft(2)) net-positive-energy urban office building in Seattle, WA, USA, is one of the most energy-efficient buildings in the world (2013 WAN Sustainable Building of the Year Winner). Its measured energy consumption in 2015 was approximately 34.8 kWh/(m(2)a (TM) yr) (11 kBtu/(ft(2)a (TM) yr)). Occupant behavior exerts an out-sized influence on the energy performance of the building. Nearly 33% of the end-use energy consumption at the Bullitt Center consists of unregulated miscellaneous electrical loads (plug-loads), which are directly attributable to occupant behavior and equipment procurement choices. Approximately 16% of end-use energy is attributable to electric lighting which is also largely determined by occupant behavior. Key to the building's energy efficiency is employment of lighting controls and daylighting strategies to minimize the lighting load. This paper uses measured energy use in a 330 m(2) (3550 ft(2)) open office space in this building to inform occupant profiles that are then modified to create four scenarios to model the impact of behavior on lighting use. By using measured energy consumption and an energy model to simulate the energy performance of this space, this paper evaluates the potential energy savings based on different occupant behavior. This paper describes occupant behavior simulation methods and evaluates them using a robust dataset of 15 minute interval sub-metered energy consumption data. Lighting control strategies are compared via simulation results, in order to achieve the best match between occupant schedules, controls, and energy savings. Using these findings, we propose a simulation methodology that incorporates measured energy use data to generate occupant schedules and control schemes with the ultimate aim of using simulation results to evaluate energy saving measures that target occupant behavior.

Keywords

Control-systems; Patterns; Offices; Lighting Control; Ultra-low Energy Building; Occupant Behavior; Building Simulation; Energy Consumption

Introducing Supergrids, Superblocks, Areas, Networks, and Levels to Urban Morphological Analyses

Moudon, Anne Vernez. (2019). Introducing Supergrids, Superblocks, Areas, Networks, and Levels to Urban Morphological Analyses. Iconarp International Journal Of Architecture And Planning, 7, 1 – 14.

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Abstract

Urban morphological analyses have identified the parcel (plot), the building type, or the plan unit (tessuto in Italian) as the basic elements of urban form. As cities have grown in geographic size disproportionately to their growth in population over the past seven decades, new elements have been introduced that structure their form. This essay describes these new elements and proposes that they be formally recognized in urban morphology. It introduces a conceptual framework for a multilevel structure of urban space using areas and networks and including supergrids and superblocks to guide morphological analyses.

Keywords

Morphological Elements; A Posteriori Approach; A Priori Approach

Disruptive Information Exchange Requirements in Construction Projects: Perception and Response Patterns

Abdirad, Hamid; Dossick, Carrie S.; Johnson, Brian R.; Migliaccio, Giovanni. (2021). Disruptive Information Exchange Requirements in Construction Projects: Perception and Response Patterns. Building Research And Information, 49(2), 161 – 178.

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Abstract

The current proliferation of custom information exchange initiatives in projects disrupts information exchange routines of design and construction firms. This paper investigates how firms perceive, interpret, and act upon information exchange requirements that do not align with their existing routines. This case study examines a construction project for which the owner specified highly custom requirements for digital production and delivery of project submittals. Using ethnographic methods, the project parties' existing routines and their patterns of perceiving and responding to the requirements were identified. These patterns showed that the parties perceived disruptions to the existing dispositions and rules that guided their routines and shaped their performance across projects. The project parties used a combination of deductive, inductive, and abductive reasoning mechanisms to interpret the requirements, expose the inefficiencies associated with their workflows, and set new ground rules for action. The grounded propositions in this study hold that the limited opportunities for inductive reasoning and reflective assessment of workflows in projects can press project parties into identifying alternative workflows through cognitive search and abductive reasoning. This, in turn, results in highly situated, temporary, and fragmented workflows that are not durable and effective to contribute to refinement of existing information exchange routines.

Keywords

Construction Industry; Abductive Reasoning; Cognitive Searches; Construction Projects; Design And Construction; Ethnographic Methods; Inductive Reasoning; Information Exchange Requirements; Information Exchanges; Organizational Routines; Risk; Bim; Implementation; Innovation; Information Exchange; Disruptive Requirements; Routines; Construction Companies; Cognitive Ability; Project Engineering; Reasoning

Design Of Broadband Helmholtz Resonator Arrays Using The Radiation Impedance Method.

Rajendran, Vidhya; Piacsek, Andy; Méndez Echenagucia, Tomás. (2022). Design Of Broadband Helmholtz Resonator Arrays Using The Radiation Impedance Method. Journal Of The Acoustical Society Of America, 151(1), 457 – 466.

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Abstract

This paper describes the design process of a low-frequency sound absorptive panel composed of differently tuned Helmholtz resonators (HRs), considering size and fabrication constraints relevant for applications in the building sector. The paper focuses on cylindrical and spiral resonators with embedded necks that are thin and can achieve high absorption. the mutual interaction between the resonators was modeled based on the radiation impedance method and it plays a key component in enhancing the absorption performance of the array. The differential evolution search algorithm was used to design the resonators and modify their mutual interaction to derive the absorption performance of multiple HR arrays for comparison. Optimizations to the resonator configuration and the neck resistance were implemented to produce a unit panel that has a broadband absorption performance with emphasis on the low to mid frequencies and is thin and light in weight. Unit panels with dimensions of 20 cm x 20 cm , consisting of 29 cylindrical HRs designed to absorb in the 25–900 Hz frequency range, were constructed and tested in a custom-built impedance tube. The measured absorption performance of these panels is consistent with the theoretical predictions. [ABSTRACT FROM AUTHOR]; Copyright of Journal of the Acoustical Society of America is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Keywords

Helmholtz Resonators; Differential Evolution; Search Algorithms; Radiation; Structural Optimization; Resonators; Bandpass Filters

Automated Task-Level Activity Analysis through Fusion of Real Time Location Sensors and Worker’s Thoracic Posture Data

Cheng, Tao; Teizer, Jochen; Migliaccio, Giovanni C.; Gatti, Umberto C. (2013). Automated Task-Level Activity Analysis through Fusion of Real Time Location Sensors and Worker’s Thoracic Posture Data. Automation In Construction, 29, 24 – 39.

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Abstract

Knowledge of workforce productivity and activity is crucial for determining whether a construction project can be accomplished on time and within budget. Significant work has been done on improving and assessing productivity and activity at task, project, or industry levels. Task level productivity and activity analysis are used extensively within the construction industry for various purposes, including cost estimating, claim evaluation, and day-to-day project management. The assessment is mostly performed through visual observations and after-the-fact analyses even though previous studies show automatic translation of operations data into productivity information and provide spatial information of resources for specific construction operations. An original approach is presented that automatically assesses labor activity. Using data fusion of spatio-temporal and workers' thoracic posture data, a framework was developed for identifying and understanding the worker's activity type over time. This information is used to perform automatic work sampling that is expected to facilitate real-time productivity assessment. Published by Elsevier B.V.

Keywords

Detectors; Construction Projects; Labor Supply; Real-time Control; Construction Costs; Project Management; Machine Translating; Activity And Task Analysis; Construction Worker; Data Fusion; Health; Location Tracking; Productivity; Safety; Sensors; Thoracic Posture Data; Workforce; Construction Industry; Costing; Labour Resources; Sensor Fusion; Real-time Productivity Assessment; Automatic Work Sampling; Worker Activity Type; Spatio-temporal Data; Labor Activity Assessment; Construction Operations; Spatial Information; Productivity Information; Day-to-day Project Management; Claim Evaluation; Cost Estimating; Task Level Productivity; Industry Levels; Project Levels; Construction Project; Workforce Activity; Workforce Productivity; Worker Thoracic Posture Data; Real Time Location Sensors Fusion; Automated Task-level Activity Analysis; Construction-industry Productivity

Efficiency Index for Fiber-Reinforced Concrete Lining at Ultimate Limit State

Fantilli, Alessandro P.; Nemati, Kamran M.; Chiaia, Bernardino. (2016). Efficiency Index for Fiber-Reinforced Concrete Lining at Ultimate Limit State. Sustainable And Resilient Infrastructure, 1(1-2), 84 – 91.

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Abstract

The fiber contribution to the ultimate limit state capacity of precast and cast-in situ tunnel linings is analytically investigated. By means of a numerical model, capable of computing the interaction curves of reinforced concrete cross sections subjected to combined compressive and bending actions, the mechanical performances of plain and fiber-reinforced concrete are compared. As a result, a new index is introduced to quantify the effectiveness of fiber addition. The higher the efficiency index, the higher the amount of steel reinforcing bar that can be removed from a plain concrete cross section. The application to real concrete linings, where shear resistance is ensured without shear reinforcement, shows that a large volume of rebar can be saved by the presence of steel fibers. This gives significant advantages in terms of durability and rapidity of tunnel construction.

Keywords

Fiber-reinforced Concrete; Efficiency Index; Ultimate Limit State; Cast-in Situ Concrete Lining; Precast Tunnel Segments

In Situ Measurement of Wind Pressure Loadings on Pedestal Style Rooftop Photovoltaic Panels

Bender, W.; Waytuck, D.; Wang, S.; Reed, D. A. (2018). In Situ Measurement of Wind Pressure Loadings on Pedestal Style Rooftop Photovoltaic Panels. Engineering Structures, 163, 281 – 293.

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Abstract

The installation of rooftop photovoltaic (PV) arrays is increasing throughout the US. Until recently, pedestal type PV framing systems for rooftops were basically designed using procedures from the ASCE7-10 Components and Cladding Standard for rooftop equipment. The 2011 Japanese Standard Load design guide on structures for photovoltaic arrays was useful in characterizing the pressure coefficients on rooftops, but the Standard employs different wind speed and importance factors, making its use in the US quite limited, Even the updated 2017 version is written for a different audience. Because rooftop pressure loadings are high due to flow separation, SEAOC and other organizations contracted boundary layer wind tunnel tests of panels attached to rooftops to ascertain if the ASCE7-10 equipment loadings were appropriate. The investigations resulted in new standards for pedestal-style arrays that appear in Chapter 29 of ASCE7-16. However, the new standards are limited to simple geometries and orientations, and the dynamics of the simply-supported thin PV plates do not appear to be considered. Questions regarding the ability of the boundary tunnels to simulate accurately the turbulence at the scale required for the attached panels have been raised. In response, very limited full-scale investigations in large-scale tunnels and in situ have been undertaken to calibrate the tunnel results. The results of this paper represent one of these calibration investigations. Specifically, in situ full-scale net wind pressure loadings on a rooftop PV array in a pedestal-style framing system located on the three story Hogue Technology Building of Central Washington University (CWU) in Ellensburg, Washington were measured. The CWU campus has a rural setting in a region with steady winds: Ellensburg is located in the Kittitas Breezeway portion of the Northwest wind power region. Indeed, the Wild Horse Wind and Solar Farm is located on the outskirts of town. The data described here were collected from April through August 2014. The measured net pressure coefficient time series were similar to those for rooftop pressure loadings for low-rise buildings described in the literature such as the Wind Engineering Research Field Laboratory at Texas Tech University (Ham and Bienkiewicz, 1998 [1]; Levitan and Mehta, 1992 [2]). The analysis of the net pressure time series data included an examination of the minimum, maximum, mean, and RMS values. Preliminary results suggest that the range of the values is larger than assumed in the ASCE7 Standard, and that the magnitude of the loadings vary considerably spatially over the multiple panel array. The pressure loading measurements are ongoing.

Keywords

Building Integrated Photovoltaics; Buildings (structures); Calibration; Design Engineering; Pressure Measurement; Roofs; Solar Cell Arrays; Standards; Time Series; Turbulence; Wind Tunnels; Japanese Standard Load Design Guide; Wind Pressure Loading Measurements; Asce7-10 Components-cladding Standard; Tunnel Calibration; Texas Tech University; Kittitas Breezeway Portion; Wild Horse Wind And Solar Farm; Ellensburg; Central Washington University; Hogue Technology Building; Boundary Layer Wind Tunnel Test; Flow Separation; Multiple Panel Array; Wind Engineering Research Field Laboratory; Net Pressure Coefficient Time Series; Northwest Wind Power Region; Pedestal-style Framing System; Pv Plates; Rooftop Equipment; Pedestal Style Rooftop Photovoltaic Panels; Solar-arrays; Loads; Simulation; Wind Engineering; Photovoltaic Modules; Solar Energy; Full-scale Measurements; Wind Loadings; Photovoltaic Cells; Roofing; Wind Power; Structural Engineering; Boundary Layers; Cladding; Wind Tunnel Testing; Solar Cells; In Situ Measurement; Framing; Photovoltaics; Engineering Research; Wind Measurement; Pressure; Panels; Wind Pressure; Design Standards; Fluid Dynamics; Low Rise Buildings; Colleges & Universities; Wind Speed; United States--us

Urban Systems Design: A Conceptual Framework for Planning Smart Communities

Tobey, Michael B.; Binder, Robert B.; Chang, Soowon; Yoshida, Takahiro; Yamagata, Yoshiki; Yang, Perry P. J. (2019). Urban Systems Design: A Conceptual Framework for Planning Smart Communities. Smart Cities, 2(4), 522 – 537.

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Abstract

Urban systems design arises from disparate current planning approaches (urban design, Planning Support Systems, and community engagement), compounded by the reemergence of rational planning methods from new technology (Internet of Things (IoT), metric based analysis, and big data). The proposed methods join social considerations (Human Well-Being), environmental needs (Sustainability), climate change and disaster mitigation (Resilience), and prosperity (Economics) as the four foundational pillars. Urban systems design integrates planning methodologies to systematically tackle urban challenges, using IoT and rational methods, while human beings form the core of all analysis and objectives. Our approach utilizes an iterative three-phase development loop to contextualize, evaluate, plan and design scenarios for the specific needs of communities. An equal emphasis is placed on feedback loops through analysis and design, to achieve the end goal of building smart communities.

Keywords

Urban Design; Planning Support System; Resilience; Sustainability; Economics; Human Factors; Big Data

Toward a Cross-Platform Framework: Assessing the Comprehensiveness of Online Rental Listings

Costa, Ana; Sass, Victoria; Kennedy, Ian; Roy, Roshni; Walter, Rebecca J.; Acolin, Arthur; Crowder, Kyle; Hess, Chris; Ramiller, Alex; Chasins, Sarah. (2021). Toward a Cross-Platform Framework: Assessing the Comprehensiveness of Online Rental Listings. Cityscape, 23(2), 327 – 339.

Abstract

Research on rental housing markets in the United States has traditionally relied on national or local housing surveys. Those sources lack temporal and spatial specificity, limiting their use for tracking short-term changes in local markets. As rental housing ads have transitioned to digital spaces, a growing body of literature has utilized web scraping to analyze listing practices and variations in rental market dynamics. Those studies have primarily relied on one platform, Craigslist, as a source of data. Despite Craigslist's popularity, the authors contend that rental listings from various websites, rather than from individual ones, provide a more comprehensive picture. Using a mixed-methods approach to study listings across various platforms in five metropolitan areas, this article demonstrates considerable variation in both the types of rental units advertised and the features provided across those platforms. The article begins with an account of the birth and consolidation of online rental platforms and emergent characteristics of several selected websites, including the criteria for posting, search parameters, search results priority, and first-page search results. Visualizations are used to compare features such as the 40th percentile of rent, rent distribution, and bedroom size based on scraped data from six online platforms (Padmapper, Forrent.com , Trulia, Zillow, Craigslist, and GoSection8), 2020 Fair Market Rents, and 2019 American Community Survey data. The analyses indicate that online listing platforms target different audiences and offer distinct information on units within those market segments, resulting in markedly different estimates of local rental costs and unit size distribution depending on the platform.

Evaluation of Sky Spectra and Sky Models in Daylighting Simulations

Inanici, M; Abboushi, B; Safranek, S. (2022). Evaluation of Sky Spectra and Sky Models in Daylighting Simulations. Lighting Research & Technology, 1.

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Abstract

Sky models in daylight simulations represent the luminance variation across the sky-dome for different locations, dates, times and weather conditions, but skies are typically modelled as colourless. Recent studies explore techniques for incorporating the spectral content of daylighting in simulations. This paper provides an evaluation of the existing spectral sky models in lighting simulation software. The comparisons are made between the available mathematical sky models and naturally occurring skies that were recorded using high dynamic range photography and spectrophotometric measurements. The results show that recently developed sky models present progress compared to colourless sky models, but further research is needed to accurately simulate daylight spectra. [ABSTRACT FROM AUTHOR]; Copyright of Lighting Research & Technology is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)