Design & Building Archives - Page 32 of 42

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.

View Publication

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

Cybergrid: A Virtual Workspace for Architecture, Engineering, and Construction

Taylor, John E.; Alin, Pauli; Anderson, Anne; Çomu, Semra; Dossick, Carrie Sturts; Hartmann, Timo; Iorio, Josh; Mahalingam, Ashwin; Mohammadi, Neda. (2018). Cybergrid: A Virtual Workspace for Architecture, Engineering, and Construction. Transforming Engineering Education: Innovative, Computer-mediated Learning Technologies, 291-321.

View Publication

Abstract

Projects in the architecture, engineering and construction (AEC) industry frequently involve a large number of firms that increasingly span national boundaries. National boundary spanning by AEC firms engaged in complex, interdependent work introduces coordination challenges because stakeholders may not share the same language, culture or work practices. These types of firms have begun to explore the use of technologies that can meaningfully create productive work connections between the distributed participants 47 and help improve work coordination and execution. In this chapter, we describe the CyberGRID (Cyber-enabled Global Research Infrastructure for Design); a virtual workspace designed to support geographically distributed AEC work coordination and execution. The CyberGRID was created as a research tool to both enable and study virtual AEC teamwork. We summarize findings from multiple experiments over the jive year history of CyberGRID research and development. These findings help to improve our understanding of interactional dynamics among virtual teams in complex sociotechnical systems like the CyberGRID. We then discuss the challenges faced in developing the CyberGRID and in achieving widespread adoption of such tools in the industry. We close the chapter with a discussion of future research opportunities to develop improved sociotechnical systems to better support the execution of AEC projects. Our goal with this chapter is to argue that sociotechnical systems like the CyberGRID can fundamentally and positively transform the interactional dynamics of AEC project stakeholders to create more efficient global virtual work practices.

Keywords

Civil Engineering Computing; Construction Industry; Data Visualisation; Groupware; Project Management; Team Working; Virtual Reality; Cybergrid; Virtual Workspace; Construction; Engineering; National Boundaries; National Boundary Spanning; Aec Firms; Complex Work; Interdependent Work; Coordination Challenges; Culture; Productive Work Connections; Chapter; Global Research Infrastructure; Geographically Distributed Aec Work Coordination; Research Tool; Virtual Aec Teamwork; Virtual Teams; Complex Sociotechnical Systems; Future Research Opportunities; Improved Sociotechnical Systems; Aec Projects; Aec Project Stakeholders; Efficient Global Virtual Work Practices

Environmental Benefits of Using Hybrid CLT Structure in Midrise Non-Residential Construction: An LCA Based Comparative Case Study in the U.S. Pacific Northwest

Pierobon, Francesca; Huang, Monica; Simonen, Kathrina; Ganguly, Indroneil. (2019). Environmental Benefits of Using Hybrid CLT Structure in Midrise Non-Residential Construction: An LCA Based Comparative Case Study in the U.S. Pacific Northwest. Journal Of Building Engineering, 26.

View Publication

Abstract

In this study, the cradle-to-gate environmental impact of a hybrid, mid-rise, cross-laminated timber (CLT) commercial building is evaluated and compared to that of a reinforced concrete building with similar functional characteristics. This study evaluates the embodied emissions and energy associated with building materials, manufacturing, and construction. Two alternative designs are considered for fire protection in the hybrid CLT building: 1) a 'fireproofing design', where gypsum wallboard is applied to the structural wood; and 2) a 'charring design', where two extra layers of CLT are added to the panel. The life cycle environmental impacts are assessed using TRACI 2.1 and the total primary energy is evaluated using the Cumulative Energy Demand impact method. Results show that an average of 26.5% reduction in the global warming potential is achieved in the hybrid CLT building compared to the concrete building, excluding biogenic carbon emissions. Except ozone depletion, where the difference in impact between scenarios is < 1%, replacing fireproofing with charring is beneficial for all impact categories. The embodied energy assessment of the building types reveals that, on average, the total primary energy in the hybrid CLT buildings and concrete building are similar. However, the non-renewable energy (fossil-based) use in the hybrid CLT building is 8% lower compared to that of the concrete building. As compared to the concrete building, additional 1,556 tCO(2)(e) and 2,567 tCO(2e) are stored in the wood components of the building (long-term storage of biogenic carbon) in the scenario with fireproofing and with charring, respectively.

Keywords

Wood; Concrete; Energy; Buildings; Impacts; Cross-laminated Timber; U.s. Pacific Northwest; Life Cycle Assessment; Cumulative Energy Demand; Biogenic Carbon; Carbon Storage

The Impact of Empowering Front-Line Managers on Planning Reliability and Project Schedule Performance

Kim, Yong-Woo; Rhee, Byong-Duk. (2020). The Impact of Empowering Front-Line Managers on Planning Reliability and Project Schedule Performance. Journal Of Management In Engineering, 36(3).

View Publication

Abstract

This study applies empowerment theory to production planning at the level of frontline managers in a construction project. Using structural equation modeling, we investigate how empowering frontline managers impacts their planning performance. In contrast to prior studies, we find that although psychological empowerment of frontline managers has no direct effect on their production planning reliability or scheduling performance, it has an indirect effect on planning reliability and scheduling performance, as long as the organization supports the empowerment structurally during production planning. This implies that a project manager should provide frontline managers at the operational level with proper formal and informal authority over workflow development, shielding, and resource allocation when planning production in order to enhance job performance through psychological empowerment. This study contributes to the body of knowledge on construction management by exploring the impact of psychological and structural empowerment of frontline managers on their performance of production planning reliability and scheduling performance.

Keywords

Psychological Empowerment; Work; Model; Variables; System; Job; Planning Reliability; Production Planning; Scheduling Performance; Structural Empowerment; Structural Equation Modeling

Does the Built Environment Have Independent Obesogenic Power? Urban Form and Trajectories of Weight Gain

Buszkiewicz, James H.; Bobb, Jennifer F.; Hurvitz, Philip M.; Arterburn, David; Moudon, Anne Vernez; Cook, Andrea; Mooney, Stephen J.; Cruz, Maricela; Gupta, Shilpi; Lozano, Paula; Rosenberg, Dori E.; Theis, Mary Kay; Anau, Jane; Drewnowski, Adam. (2021). Does the Built Environment Have Independent Obesogenic Power? Urban Form and Trajectories of Weight Gain. International Journal Of Obesity, 45(9), 1914 – 1924.

View Publication

Abstract

Objective To determine whether selected features of the built environment can predict weight gain in a large longitudinal cohort of adults. Methods Weight trajectories over a 5-year period were obtained from electronic health records for 115,260 insured patients aged 18-64 years in the Kaiser Permanente Washington health care system. Home addresses were geocoded using ArcGIS. Built environment variables were population, residential unit, and road intersection densities captured using Euclidean-based SmartMaps at 800-m buffers. Counts of area supermarkets and fast food restaurants were obtained using network-based SmartMaps at 1600, and 5000-m buffers. Property values were a measure of socioeconomic status. Linear mixed effects models tested whether built environment variables at baseline were associated with long-term weight gain, adjusting for sex, age, race/ethnicity, Medicaid insurance, body weight, and residential property values. Results Built environment variables at baseline were associated with differences in baseline obesity prevalence and body mass index but had limited impact on weight trajectories. Mean weight gain for the full cohort was 0.06 kg at 1 year (95% CI: 0.03, 0.10); 0.64 kg at 3 years (95% CI: 0.59, 0.68), and 0.95 kg at 5 years (95% CI: 0.90, 1.00). In adjusted regression models, the top tertile of density metrics and frequency counts were associated with lower weight gain at 5-years follow-up compared to the bottom tertiles, though the mean differences in weight change for each follow-up year (1, 3, and 5) did not exceed 0.5 kg. Conclusions Built environment variables that were associated with higher obesity prevalence at baseline had limited independent obesogenic power with respect to weight gain over time. Residential unit density had the strongest negative association with weight gain. Future work on the influence of built environment variables on health should also examine social context, including residential segregation and residential mobility.

Keywords

Body-mass Index; Physical-activity; Food Environment; Structural Racism; Obesity; Neighborhoods; Associations; Health; Walkability; Exposure; Environment Models; Minority & Ethnic Groups; Urban Environments; Regression Analysis; Regression Models; Residential Density; Body Mass Index; Property Values; Body Weight Gain; Government Programs; Body Weight; Electronic Medical Records; Electronic Health Records; Fast Food; Buffers; Real Estate; Body Mass; Body Size; Socioeconomics; Health Care

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.

View Publication

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

Elizabeth Golden and team at united4design shortlisted for Aga Khan Award in architecture

The Aga Khan Award for Architecture (AKAA) recently announced 20 shortlisted projects for the 2022 Award cycle. The projects will compete for a share of the US$ 1 million prize, one of the largest in architecture. The 20 shortlisted projects were selected by an independent Master Jury from a pool of 463 projects nominated for the 15th Award Cycle (2020-2022). The Aga Khan Award for Architecture was established by His Highness the Aga Khan in 1977 to identify and encourage…

Carbon Leadership Forum awarded ARPA-E grant to develop life cycle assessment tools for carbon negative buildings

ARPA-E announced $5 million in funding to two universities—the University of Washington and University of California, Davis—working to develop life cycle assessment tools and frameworks associated with transforming buildings into net carbon storage structures. The funding is part of the Harnessing Emissions into Structures Taking Inputs from the Atmosphere (HESTIA) Exploratory Topic. Parametric Open Data for Life Cycle Assessment (POD | LCA) – $3,744,303 The University of Washington’s Carbon Leadership Forum will develop a rigorous and flexible parametric Life Cycle Assessment (LCA)…

Ann Marie Borys publishes book on American Unitarian churches

Ann Marie Borys, Associate Professor in Architecture recently published a book titled American Unitarian Churches: Architecture of a Democratic Religion. The Unitarian religious tradition was a product of the same eighteenth-century democratic ideals that fueled the American Revolution and informed the founding of the United States. Its liberal humanistic principles influenced institutions such as Harvard University and philosophical movements like Transcendentalism. Yet, its role in the history of American architecture is little known and studied. In American Unitarian Churches, Ann Marie…

2022 CBE Inspire Fund awardees announced

In 2021 the College of Built Environments launched the CBE Inspire Fund, designed to support CBE research activities for which a relatively small amount of support can be transformative. The second year of awards have just been announced, supporting five projects across 4 departments within the college as they address topics such as food sovereignty, anti-displacement, affordable housing, and health & wellbeing. This year’s awardees include: Defining the New Diaspora: Where Seattle’s Black Church Congregants Are Moving and Why Rachel…