Skip to content

Tri-stimulus Color Accuracy in Image-based Sky Models: Simulating the Impact of Color Distributions throughout the Sky Dome on Daylit Interiors with Different Orientations

Inanici, M. (2019). Tri-stimulus Color Accuracy in Image-based Sky Models: Simulating the Impact of Color Distributions throughout the Sky Dome on Daylit Interiors with Different Orientations. Proceedings of Building Simulation 2019: 16th Conference of IBPSA. https://doi.org/10.26868/25222708.2019.210585.

View Publication

Abstract

Spectral properties of daylight surpasses any other light source. Its dynamic intensity and spectra across the full spectrum facilitates sustainable daylighting practices, produces best color rendition, and regulates circadian rhythms in all living beings. However, simulation models do not typically include spectral variability; daylight is modelled as a uniform, equal energy white source. In this paper, tristimulus calibration procedures are utilized to create spectrally accurate High Dynamic Range (HDR) photographs. HDR photographs of skies are collected and utilized as an input to image based lighting (IBL) simulations. The impact of color variations across the sky dome and between different sky conditions are studied. Per-pixel photopic luminances, tri-stimulus chromatic distributions, Correlated Color Temperatures (CCT) and circadian luminance and illuminance values are quantified for image-based daylighting simulations, and compared with standard colorless Perez skies.

Keywords

color based skies; image based lighting; daylight simulations; high dynamic range imagery; color calibration

Performative By-Products: The Emergence of Waste Reuse Strategies at the Blue Lagoon

De Almeida, Catherine. (2019). Performative By-Products: The Emergence of Waste Reuse Strategies at the Blue Lagoon. Journal of Landscape Architecture, 13(3), 64-77.

View Publication

Abstract

Materials and landscapes associated with waste are perceived as objectionable. By reactivating and embracing waste conditions as desirable opportunities for diverse programmes rooted in economy, ecology, and culture, designers can form hybrid assemblages on waste sites through the exchange of waste materials—a landscape lifecycles approach. This frame-work is applicable to not only design research, but also as a critical lens for evaluating the landscape performance of existing projects that engage with waste reuse. The Blue Lagoon in southwest Iceland materialized as a spa industry out of geothermal waste effluent from the adjacent Svartsengi Geothermal Power Station, reusing undesirable materials and transforming a waste landscape through diversified material recovery strategies. Featuring an industrial by-product turned economic generator, this case study reveals the opportunities for reusing geothermal ‘waste’ in these emergent landscape conditions, which hybridize economies with recreation, research, and ecology, and shift the conventional relationship with waste from passive to performative.

Keywords

Waste reuse; Blue Lagoon; material lifecycles; Iceland; landscape reclamation

Comparing Small Area Fair Market Rents with Other Rental Measures across Diverse Housing Markets

Hess, Christian; Walter, Rebecca J.; Acolin, Arthur; Chasins, Sarah. (2019). Comparing Small Area Fair Market Rents with Other Rental Measures across Diverse Housing Markets. Cityscape, 21(3), 159 – 186.

View Publication

Abstract

Small Area Fair Market Rents (SAFMRs) are calculated at the 40th percentile of the U.S. postal ZIP Code instead of the metropolitan area in an effort to capture localized rents to expand choice for voucher holders to access housing in higher-opportunity neighborhoods. Existing studies on the potential and actual outcomes of SAFMRs demonstrate that findings vary for different types of housing markets. Furthermore, the decisions public housing authorities (PHAs) make in the implementation process affect PHAs' program budget and the rent burden and locational outcomes for voucher households. This study aims to address how these implementation factors are affected by local rental market conditions for three PHAs-Housing Authority of the City of Fort Lauderdale, San Antonio Housing Authority, and Seattle Housing Authority-in diverse housing markets. By comparing different sources of market rent estimates with SAFMRs in each location, we contribute new information about how this rule is likely to produce different residential outcomes in terms of increased access to low-poverty neighborhoods and adjustments to payment standards in low-rent neighborhoods. The findings reveal differences across rent measures in terms of estimated levels and relative differences across ZIP Codes. These findings suggest that housing authorities may face challenges in meeting the objectives of the SAFMR final rule without some form of local adjustments.]

The Determinants of Executive Compensation in US REITs: Performance vs. Corporate Governance Factors

Ascherl, Claudia; Schrand, Liesa; Schaefers, Wolfgang; Dermisi, Sofia. (2019). The Determinants of Executive Compensation in US REITs: Performance vs. Corporate Governance Factors. Journal Of Property Research, 36(4), 313 – 342.

View Publication

Abstract

The paper examines whether executive compensation packages within the US REIT industry are determined merely by performance or also by CEO power mechanisms that have an essential influence on board-level negotiations. We offer original insights into management compensation arrangements during and after the financial crisis. The relative importance of cash bonuses in CEO compensation contracts has more than halved after the crisis. Simultaneously, after the financial crisis, equity-based compensation became increasingly important. Concerning the pay-for-performance link, our results show no relationship during the financial crisis. However, after the crisis, we find a strong significant link between remuneration packages and corporate success.

Keywords

Executive Compensation; Chief Executive Officers; Negotiations; Compensation; Packages; Crises; Economic Crisis; Corporate Governance; United States--us

Perceptions and Expected Immediate Reactions to Severe Storm Displays

Jon, Ihnji; Huang, Shih-Kai; Lindell, Michael K. (2019). Perceptions and Expected Immediate Reactions to Severe Storm Displays. Risk Analysis, 39(1), 274 – 290.

View Publication

Abstract

The National Weather Service has adopted warning polygons that more specifically indicate the risk area than its previous county-wide warnings. However, these polygons are not defined in terms of numerical strike probabilities (p(s)). To better understand people's interpretations of warning polygons, 167 participants were shown 23 hypothetical scenarios in one of three information conditions-polygon-only (Condition A), polygon + tornadic storm cell (Condition B), and polygon + tornadic storm cell + flanking nontornadic storm cells (Condition C). Participants judged each polygon's p(s) and reported the likelihood of taking nine different response actions. The polygon-only condition replicated the results of previous studies; p(s) was highest at the polygon's centroid and declined in all directions from there. The two conditions displaying storm cells differed from the polygon-only condition only in having p(s) just as high at the polygon's edge nearest the storm cell as at its centroid. Overall, p(s) values were positively correlated with expectations of continuing normal activities, seeking information from social sources, seeking shelter, and evacuating by car. These results indicate that participants make more appropriate p(s) judgments when polygons are presented in their natural context of radar displays than when they are presented in isolation. However, the fact that p(s) judgments had moderately positive correlations with both sheltering (a generally appropriate response) and evacuation (a generally inappropriate response) suggests that experiment participants experience the same ambivalence about these two protective actions as people threatened by actual tornadoes.

Keywords

Decision-making; Tornado; Risk; Communication; Numeracy; Residents; Shelter; Events; Protective Actions; Risk Perceptions; Tornado Warning Polygons; Judgments; Tornadoes; Meteorological Services; Storms; Lymphocytes B; Polygons; Emergency Warning Programs; Evacuation; Displays; Inappropriateness; Weather; Warnings; Conditions; Ambivalence

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

Reintegrating The North American Beaver (castor Canadensis) In The Urban Landscape.

Bailey, David R.; Dittbrenner, Benjamin J.; Yocom, Ken P. (2019). Reintegrating The North American Beaver (castor Canadensis) In The Urban Landscape. Wires Water, 6(1).

View Publication

Abstract

In recent decades, ecological restoration and landscape architecture have focused on reintegrating ecological processes in the urban environment to support greater habitat complexity and increase biodiversity. As these values are more broadly recognized, new approaches are being investigated to increase ecosystem services and ecological benefits in urban areas. Ecosystem engineers, such as the North American beaver (Castor canadensis), can create complex habitat and influence ecological processes in natural environments. Through dam building and wetland formation, beaver can create fish habitat, diversify vegetation in riparian zones, and aggrade sediment to increase stream productivity. As beaver populations have increased in urban areas across North America, their presence presents challenges and opportunities. Beaver can be integrated into the design of new and established urban green spaces to improve ecosystem functions. If managed properly, the conflicts that beaver sometimes create can be minimized. In this paper, we examine how landscape architects and restoration ecologists are anticipating the geomorphic and hydrological implications of beaver reintroduction in the design of wetlands and urban natural areas at regional and site levels. We present an urban beaver map and three case studies in Seattle, WA, USA, to identify various approaches, successes, and management strategies for integrating the actions of beaver into project designs. We make recommendations for how designers can capitalize on the benefits of beaver by identifying sites with increased likelihood of colonization, leveraging ecosystem engineers in design conception, designing site features to reduce constraints for the reintroduction and establishment of beaver, and anticipating and managing impacts. This article is categorized under: Water and Life > Conservation, Management, and Awareness Engineering Water > Planning Water

Keywords

Beavers; Cities & Towns In Art; Nature; Riparian Areas; Municipal Water Supply; Restoration Ecology; Wetland Ecology; United States; Seattle (wash.); North America; Beaver; Biodiversity; Castor Canadensis; Ecological Design; Ecological Restoration; Ecosystem Engineers; Ecosystem Services; Species Richness; Wetland Habitat; River-basin; Dams; Channel; Streams; Impact; Water; Ponds; Ecology; Urban Populations; Habitats; Ecosystem Management; Landscape Architecture; Colonization; Fish; Geomorphology; Habitat; Design; Ecological Monitoring; Landscape; Urban Areas; Restoration; Riparian Environments; Ecosystems; Wetlands; Ecologists; Reintroduction; Case Studies; Environmental Restoration; Open Spaces; Freshwater Mammals; Urban Environments; Aquatic Mammals; Water Conservation; Ecological Effects; Disputes; Design Engineering; Dam Construction; Engineers; Urban Planning; Complexity; Hydrology

Measuring Circadian Lighting through High Dynamic Range Photography

Jung, B.; Inanici, M. (2019). Measuring Circadian Lighting through High Dynamic Range Photography. Lighting Research & Technology, 51(5), 742 – 763.

View Publication

Abstract

The human ocular system functions in a dual manner. While the most well-known function is to facilitate vision, a growing body of research demonstrates its role in resetting the internal body clock to synchronize with the 24-hour daily cycle. Most research on circadian rhythms is performed in controlled laboratory environments. Little is known about the variability of circadian light within the built and natural environments. Currently, very few specialized devices measure the circadian light, and they are not accessible to many researchers and practitioners. In this paper, tristimulus colour calibration procedures for high dynamic range photography are developed to measure circadian lighting. Camera colour accuracy is evaluated through CIE trichromatic (XYZ) measurements; and the results demonstrate a strong linear relationship between the camera recordings and a scientific-grade colorimeter. Therefore, it is possible to correct for the colour aberrations and use high dynamic range photographs to measure both photopic and circadian lighting values. Spectrophotometric measurements are collected to validate the methodology. Results demonstrate that measurements from high dynamic range photographs can correspond to the physical quantity of circadian luminance with reasonable precision and repeatability. Circadian data collected in built environments can be utilized to study the impact of design decisions on human circadian entrainment and to create guidelines and metrics for designing circadian friendly environments.

Keywords

Physical Constants; Medical Photography; Photography; Built Environment; Morningness-eveningness Questionnaire; Statistical Reliability; Circadian Rhythms; Action Spectrum; Ganglion-cells; Bright Light; Exposure; Sensitivity; Framework; Daylight; Daytime; Model; Rod