Sprague, Tyler S. (2018). Jack Christiansen’s Cylindrical Concrete Shells. Journal Of The International Association For Shell And Spatial Structures, 59(2), 131 – 140.
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Abstract
This article examines the early thin shell concrete designs of the structural engineer Jack Christiansen (1927-2017), a 2016 recipient of the Eduardo Torroja Medal. With no proper training in shell behavior, Christiansen started his career designing cylindrical concrete shells based on the 1952 American Society of Civil Engineers (ASCE) Manual 31. This manual, and its approach to solving indeterminate behavior, both directed Christiansen's early design and provided a framework for significant creative work outside its bounds. His designs of long, spanning shells and short, arching shells (between 1954 and 1958) were adapted to a variety of architectural spaces, utilizing emerging structural methods like prestressing. These designs constitute the first era of Christiansen's career, and set the stage for more varied shell geometries to come.
Keywords
Historic Structures; Concrete Shells; Cylindrical Shells; Modernism; Indeterminate Analysis Methods
Colburn, Gregg. (2019). The Effect of Market Conditions on the Housing Outcomes of Subsidized Households: The Case of the US Voucher Programme. Housing Studies, 34(9), 1465 – 1484.
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Abstract
Since being created in the 1970s, housing vouchers have become the primary mode of federal housing support for low-income households in the US. The voucher programme was designed to provide recipients with the mobility needed to secure higher quality housing in neighbourhoods of their choice. Decades of analysis suggest that the programme has failed to produce the favourable outcomes envisioned by policymakers. To add to our understanding of the outcomes of this important federal programme, this paper seeks to underscore the importance of context-dependent policy analysis. In particular, this study analyses the impact of housing market conditions on the outcomes achieved by voucher recipients. Using neighbourhood and housing outcome data from the American Housing Survey, and median rent and rental market vacancy data, this paper demonstrates the important role that market conditions play in programme outcomes. The results from this study suggest that voucher recipients are successful at improving housing unit quality outcomes regardless of market conditions, but the ability to move to a better neighbourhood is a function of vacancy rates.
Keywords
Housing Subsidies; Housing Vouchers; Housing Market; Poor Communities; Neighborhoods; Housing; Housing Choice Voucher; Market; Neighbourhood; Section 8; Vacancy; Voucher; Residential-mobility Decisions; Choice Vouchers; Neighborhood; Income; Live; Families; Place; Home; Markets; Economic Conditions; Policy Analysis; Households; Impact Analysis; Policy Making; Low Income Groups; Vouchers; Mobility; Vacancies; Conditions; United States--us
Kim, Jonghyeob; Han, Sangwon; Hyun, Chang-taek. (2019). Identification and Reduction of Synchronous Replacements in Life-Cycle Cost Analysis of Equipment. Journal Of Management In Engineering, 35(1).
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Abstract
Life-cycle cost analysis (LCCA) is a methodology used to calculate the total cost of a project from initial planning to final disposal. In conventional approaches, LCCA assumes that regular and preventive maintenance will be performed according to each replacement cycle for individual components, and replacement for each component is considered independently. However, because the components of equipment used in buildings are installed systemically, replacements of major components may cause unexpected replacements of dependent minor components. Therefore, it is necessary to identify additional replacements based on the associations among these related replacement components to achieve a more reliable LCCA. In response, this study proposes an LCCA model that comprehensively considers the relationships among the maintenance components. The development of the model involves identifying relationships among components using social network analysis (SNA), arranging individual replacement timings of the components that reflect these relationships, and analyzing the life-cycle cost (LCC) based on the arranged timing. To validate the model, its applicability and effectiveness was illustrated and tested using 19 components of a rainwater reuse system. This study makes a theoretical contribution to the body of knowledge by suggesting concepts of synchronous relationships and replacements based on SNA. In addition, the use of the model proposed in this study enables practitioners to analyze LCCs that reflect synchronous replacements, which allows more reasonable decision-making considering hidden costs in conventional LCC. (C) 2018 American Society of Civil Engineers.
Keywords
Decision Making; Life Cycle Costing; Preventive Maintenance; Synchronous Replacements; Life-cycle Cost Analysis; Lcca Model; Maintenance Components; Social Network Analysis; Painted Surfaces; Decision-making; Prediction; Model; Risk; Maintenance; Replacement; Synchronous Replacement; Synchronous Relationship; Life-cycle Cost Analysis (lcca); Social Network Analysis (sna)
Scully, Jason Y.; Moudon, Anne Vernez; Hurvitz, Philip M.; Aggarwal, Anju; Drewnowski, Adam. (2019). A Time-Based Objective Measure of Exposure to the Food Environment. International Journal Of Environmental Research And Public Health, 16(7).
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Abstract
Exposure to food environments has mainly been limited to counting food outlets near participants' homes. This study considers food environment exposures in time and space using global positioning systems (GPS) records and fast food restaurants (FFRs) as the environment of interest. Data came from 412 participants (median participant age of 45) in the Seattle Obesity Study II who completed a survey, wore GPS receivers, and filled out travel logs for seven days. FFR locations were obtained from Public Health Seattle King County and geocoded. Exposure was conceptualized as contact between stressors (FFRs) and receptors (participants' mobility records from GPS data) using four proximities: 21 m, 100 m, 500 m, and 1/2 mile. Measures included count of proximal FFRs, time duration in proximity to 1 FFR, and time duration in proximity to FFRs weighted by FFR counts. Self-reported exposures (FFR visits) were excluded from these measures. Logistic regressions tested associations between one or more reported FFR visits and the three exposure measures at the four proximities. Time spent in proximity to an FFR was associated with significantly higher odds of FFR visits at all proximities. Weighted duration also showed positive associations with FFR visits at 21-m and 100-m proximities. FFR counts were not associated with FFR visits. Duration of exposure helps measure the relationship between the food environment, mobility patterns, and health behaviors. The stronger associations between exposure and outcome found at closer proximities (<100 m) need further research.
Keywords
Global Positioning Systems; Physical-activity; Health Research; Land-use; Neighborhood; Gps; Obesity; Tracking; Validity; Mobility; Fast Food; Spatio-temporal Exposure; Mobility Patterns; Selective Mobility Bias
Cheng, Renée. (2020). Opinion: Change Agency, Value Change. Architect, 109(9), 20 – 20.
Keywords
Attitude Change (psychology); Air Flow; Hand Washing
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).
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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
Rodriguez, Barbara X.; Huang, Monica; Lee, Hyun Woo; Simonen, Kathrina; Ditto, Jim. (2020). Mechanical, Electrical, Plumbing and Tenant Improvements over the Building Lifetime: Estimating Material Quantities and Embodied Carbon for Climate Change Mitigation. Energy And Buildings, 226.
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Abstract
The building industry is expanding its ability to mitigate the environmental impacts of buildings through the application of life cycle assessment (LCA). Most building LCA studies focus on core and shell (C&S) and rarely assess mechanical, electrical, and plumbing (MEP) and tenant improvements (TI). However, C&S typologies in the commercial sector pose particular challenges to achieving net zero carbon due to the numerous renovations these building undergo through during their service life. MEP and TI are installed multiple times over the lifetime of commercial buildings leading to cumulative environmental impact caused by increasing material quantities and embodied carbon (EC). This study aimed to establish a preliminary range of material quantities and embodied carbon impacts for MEP and TI components, focusing on commercial office buildings in the Pacific Northwest. The first research stage involved quantifying material quantities while a second stage aimed to calculate Embodied Carbon Coefficients (ECC) and LCA impacts using different data sources. The embodied carbon estimates ranged from 40 to 75 kg CO(2)e/m(2) for MEP and 45-135 kg CO(2)e/m(2) for TI. However, with recurring instalments during a life span of 60 years the impacts become comparable to known impacts of core and shell systems. (C) 2020 Elsevier B.V. All rights reserved.
Keywords
Embodied Carbon; Life Cycle Assessment; Tenant Improvement; Mechanical; Electrical And Plumbing
Born, Branden; Berney, Rachel; Baker, Olivia; Jones, Mark R.; King, Donald; Marcus, Dylan. (2021). Pushing Back on Displacement: Community-Based Redevelopment through Historically Black Churches. Societies, 11(1).
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Abstract
Gentrification and subsequent displacement are common problems in cities, and result in the removal of poor communities and communities of color from urban areas as they move to cheaper locations in the metropolitan region. Here we describe a community-based approach to redevelopment by historic Black churches that seeks to counter such displacement and cultural removal. We explain the history of a historically Black neighborhood in Seattle and the founding and rationale for a church-led project called the Nehemiah Initiative. Our perspective is that of participants in the work of the Nehemiah Initiative and as faculty and students from a local university partner supporting it. We conclude with policy strategies that can be used to support such redevelopment in Seattle, with understanding that some may be broadly applicable to other cities.
Keywords
Black Churches; Community Based; Displacement; Equitable Development; Faith Based; Gentrification; Housing Affordability; Redevelopment; University-community Partnership
Jung, Meen Chel; Dyson, Karen; Alberti, Marina. (2021). Urban Landscape Heterogeneity Influences the Relationship Between Tree Canopy and Land Surface Temperature. Urban Forestry & Urban Greening, 57.
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Abstract
Urban trees play a key role in alleviating elevated summertime land surface temperatures in cities. However, urban landscape influences the capacity of urban trees to mitigate higher temperatures. We propose that both developed land characteristics and tree cover should be considered to accurately estimate the mitigation effects of canopy cover. We subclassified original land cover based on the canopy cover ratio to capture the within-land cover heterogeneity. We selected two coastal cities with different summertime climatic conditions: Seattle, Washington, USA, and Baltimore, Maryland, USA. We used Landsat-based grid cells (30 m x 30 m) as our spatial analytical unit, with corresponding land surface temperature, canopy area, canopy compactness, population size, and National Land Cover Database (NLCD)-based land cover group. We first used grouped boxplots, Kruskal-Wallis H tests, and post-hoc multiple comparison tests to detect the distribution of land surface temperatures by the land cover group. We then introduced statistical models to test the group effects on the relationship between land surface temperatures and canopy cover variables. We found: (1) land surface temperature increases with level of development, (2) land surface temperature decreases with canopy cover level, (3) the magnitude of the mitigation effects from canopy area differs based on development level and current canopy cover, (4) the differing efficacies of canopy area in decreasing land surface temperature follows a nonlinear threshold relationship, and (5) compactness of canopy cover was not significant in reducing the land surface temperature. These findings suggest the importance of considering heterogeneous canopy cover within developed land cover classes in urban heat island research. Tree planting strategies need to consider the nonlinear relationships between tree canopy cover and land surface temperature alongside environmental equity concerns.
Keywords
Extreme Heat Events; Climate-change; Cover Data; Island; Pattern; Cities; Vegetation; Mortality; Phoenix; Impact; Canopy Cover; Environmental Equity; Land Cover; Land Surface Temperature; Mitigation Effect; Area; Canopy; Cells; Climatic Factors; Databases; Heat Island; Landscapes; Multiple Comparison Test; Planting; Population Size; Research; Statistical Models; Summer; Surface Temperature; Testing; Trees; Urban Forestry; Maryland
Wagenfeld, Amy; Winterbottom, Daniel. (2021). Coping on the Inside: Design for Therapeutic Incarceration Interventions – A Case Study. Work-a Journal Of Prevention Assessment & Rehabilitation, 68(1), 97 – 106.
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Abstract
BACKGROUND: Adjusting to incarceration is traumatic. An under-utilized strategy understood to buffer and counteract the negative impacts of incarceration are nature interventions. OBJECTIVE: Outcomes of an interdisciplinary design studio course focused on developing masterplans for a women's prison in the Pacific Northwest (US) are presented. Course objectives included comprehension and application of therapeutic and culturally expressive design principles to increase the benefits of environmental design within a carceral setting; collaboration, developing a deeper, more representative understanding of how design processes can improve the lives of marginalized populations; and enhancing design skills, including at masterplan and schematic scale using an iterative process and reflection. METHODS: A landscape architect, occupational therapist, and architect teaching team, with support from architects and justice specialists facilitated an elective design studio course to redesign the Washington Corrections Center for Women campus. RESULTS: In a ten-week academic quarter, six student design teams created conceptual masterplans for therapeutic outdoor spaces at the Washington Corrections Center for Women. Students presented their plans to prison staff, current and ex-offenders, and architects and landscape architects in practice, and then received positive feedback. CONCLUSION: Despite well-documented need for and value of nature interventions to improve health and wellbeing for everyone regardless of circumstance or situation, the project awaits administrative approval to move forward to installation.
Keywords
Recovery; Exposure; Health; Correctional Institutions; Environmental Justice; Therapeutic Outdoor Environments; Interdisciplinary Academic Design Studio