Hutyra, Lucy R.; Yoon, Byungman; Alberti, Marina. (2011). Terrestrial Carbon Stocks across a Gradient of Urbanization: A Study of the Seattle, WA Region. Global Change Biology, 17(2), 783 – 797.
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Abstract
Most of our global population and its CO2 emissions can be attributed to urban areas. The process of urbanization changes terrestrial carbon stocks and fluxes, which, in turn, impact ecosystem functions and atmospheric CO2 concentrations. Using the Seattle, WA, region as a case study, this paper explores the relationships between aboveground carbon stocks and land cover within an urbanizing area. The major objectives were to estimate aboveground live and dead terrestrial carbon stocks across multiple land cover classes and quantify the relationships between urban cover and vegetation across a gradient of urbanization. We established 154 sample plots in the Seattle region to assess carbon stocks as a function of distance from the urban core and land cover [urban (heavy, medium, and low), mixed forest, and conifer forest land covers]. The mean (and 95% CI) aboveground live biomass for the region was 89 +/- 22 Mg C ha-1 with an additional 11.8 +/- 4 Mg C ha-1 of coarse woody debris biomass. The average live biomass stored within forested and urban land covers was 140 +/- 40 and 18 +/- 14 Mg C ha-1, respectively, with a 57% mean vegetated canopy cover regionally. Both the total carbon stocks and mean vegetated canopy cover were surprisingly high, even within the heavily urbanized areas, well exceeding observations within other urbanizing areas and the average US forested carbon stocks. As urban land covers and populations continue to rapidly increase across the globe, these results highlight the importance of considering vegetation in urbanizing areas within the terrestrial carbon cycle.
Keywords
Urbanization & The Environment; Carbon Cycle; Carbon In Soils; Climate Change Prevention; Population & The Environment; Land Cover; Cities & Towns -- Environmental Conditions; Seattle (wash.); Washington (state); Climate Change; Development; Mitigation; Pacific Northwest; Urban; United-states; Woody Debris; Storage; Growth; Responses; Fluxes; Co2; Sequestration; Landscape; Forests
Larson, Elisabeth K.; Grimm, Nancy B. (2012). Small-Scale and Extensive Hydrogeomorphic Modification and Water Redistribution in a Desert City and Implications for Regional Nitrogen Removal. Urban Ecosystems, 15(1), 71 – 85.
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Abstract
There are numerous examples of small-scale hydrogeomorphic manipulations within urban ecosystems. These modifications are motivated both by a need to handle storm drainage and by a human desire for aquatic ecosystems as places for recreation and aesthetics. In the Phoenix Arizona metropolitan area, two examples of these local modifications are artificial lakes and stormwater retention basins. Although lakes are not a natural feature of Sonoran Desert ecosystems, numerous artificial lakes are evident in the region. Retention basins are a common landscaping practice for preventing damage from rare but potentially large storm events. Here we attempt to quantify the heretofore unknown number and extent of these designed aquatic ecosystems and consider their potential impact on hydrologic landscape connectivity and regional nitrogen (N) removal. For lakes, we found that official GIS layers from local and state agencies had significant misclassifications and omissions. We used two published GIS datasets and state impoundment-permit information to determine the number, areal extent, and water source for artificial lakes. We discovered that there are 908-1,390 lakes in the Phoenix area, with the number varying according to level of aggregation. There are no existing GIS data on retention basins, so we employed drywell-permit data to estimate that there may be 10,000 retention basins in the region. Basic data on N stocks in these ecosystems are discussed within the context of the regional N budget. Accurate data on the extent and distribution of these designed ecosystems will be vital for water-resources planning and stormwater management.
Keywords
Urban; Urbanization; Retention; Phoenix
Comu, Semra; Iorio, Josh; Taylor, John E.; Dossick, Carrie Sturts. (2013). Quantifying the Impact of Facilitation on Transactive Memory System Formation in Global Virtual Project Networks. Journal Of Construction Engineering & Management, 139(3), 294 – 303.
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Abstract
Building strong ties between geographically dispersed project participants is crucial to project success. In global project networks, many firms have adopted virtual collaboration tools to address the challenges imposed by temporal and geographical distance. Some researchers have examined the role of facilitators and found that process facilitation can improve collaboration. Research has also shown that facilitators can be drawn into content interactions, which may negatively impact collaboration effectiveness in virtual workspaces. Research to date has not quantified this negative impact. In this study, the formation and maintenance of transactive memory systems (TMS) in two facilitated and two nonfacilitated global virtual project networks were investigated, each executing a 2-month project. Using TMS formation and cohesive subgroup formation as a proxy for performance, quantitative evidence was found that demonstrates a negative impact on collaboration effectiveness when facilitators engage in content facilitation in virtual project networks. This paper shows that this negative impact restricts the establishment of TMSs. These findings have important implications for understanding and designing appropriate facilitator interactions in global virtual project networks. DOI: 10.1061/(ASCE)CO.1943-7862.0000610. (C) 2013 American Society of Civil Engineers.
Keywords
Globalisation; Groupware; International Collaboration; Production Engineering Computing; Project Management; Process Facilitation; Transactive Memory System Formation; Global Virtual Project Network; Virtual Collaboration Tool; Temporal Distance; Geographical Distance; Content Interaction; Virtual Workspace; Tms Cohesive Subgroup Formation; Content Facilitation; Knowledge Transfer; Group Cohesiveness; Group Cohesion; Performance; Teams; Models; Globalization; Networks; Project Networks; Social Network Analysis; Transactive Memory Systems; Virtual Teams
Won, Jongsung; Lee, Ghang; Dossick, Carrie; Messner, John. (2013). Where to Focus for Successful Adoption of Building Information Modeling within Organization. Journal Of Construction Engineering And Management, 139(11).
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Abstract
Suggestions abound for successful adoption of building information modeling (BIM); however, a company with limited resources cannot adopt them all. The factors that have top management priority for successful accomplishment of a task are termed critical success factors (CSFs). This paper aims to derive the CSFs for four questions commonly asked by companies in the first wave of BIM adoption: (1)What are the CSFs for adopting BIM in a company? (2)What are the CSFs for selecting projects to deploy BIM? (3)What are the CSFs for selecting BIM services? (4)What are the CSFs for selecting company-appropriate BIM software applications? A list of consideration factors was collected for each question, based on a literature review, and then refined through face-to-face interviews based on experiences of BIM experts. An international survey was conducted with leading BIM experts. From the 206 distributed surveys, 52 responses from four continents were collected. This study used quantitative data analysis to derive a manageable number (4-10) of CSFs for each category from dozens of anecdotal consideration factors. The derived CSFs are expected to be used as efficient metrics for evaluating and managing the level of BIM adoption and as a basis for developing BIM evaluation models in the future.
Keywords
Architectural Cad; Building Information Modeling; Bim; Critical Success Factors; Csf; Management; Building Information Models; Organizations; Computer Software; Building Information Modeling (bim); Critical Success Factor (csf); Organizational Strategy; Bim Software Application; Bim Service; Bim-assisted Project; Information Technologies
Gatti, Umberto C.; Migliaccio, Giovanni C.; Bogus, Susan M.; Schneider, Suzanne(3). (2014). An Exploratory Study of the Relationship between Construction Workforce Physical Strain and Task Level Productivity. Construction Management And Economics, 32(6), 548 – 564.
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Abstract
The monitoring of construction workforce physical strain can be a valuable management strategy in improving workforce productivity, safety, health, and quality of work. Nevertheless, clear relationships between workforce performance and physical strain have yet to be established. An exploratory investigation of the relationship between task level productivity and physical strain was conducted. Nine participants individually performed a four-hour simulated construction task while a wearable physiological status monitor continuously assessed their physiological condition. Heart rate, relative heart rate, and breathing rate were utilized as predictors of physical strain, and task level-single factor productivity was used as an index of productivity. Numerous regression models were generated using the collected data. This investigation initially unsuccessfully attempted to establish a relationship between physiological condition and productivity at the individual worker level. However, an analysis of the regression models showed that there is a relationship between productivity and either heart rate or relative heart rate at the group level, and that this relationship is parabolic. Breathing rate was proved to not be a significant predictor of productivity. Research results significantly improve understanding of the relationship between work physiology and task productivity. Researchers and practitioners may use the tested monitoring devices, analysis methods, and results to design further applied studies and to improve workforce productivity. © 2013 © 2013 Taylor & Francis.
Keywords
Heart; Industrial Hygiene; Occupational Risks; Personnel; Regression Analysis; Construction Workforces; Management Strategies; Occupational Health And Safety; Operations Management; Physiological Condition; Physiological Status Monitors; Work Physiology; Workforce
Wang, X.; Liu, C.; Kostyniuk, L.; Shen, Q.; Bao, S. (2014). The Influence of Street Environments on Fuel Efficiency: Insights from Naturalistic Driving. International Journal Of Environmental Science And Technology, 11(8), 2291 – 2306.
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Abstract
Fuel consumption and greenhouse gas emissions in the transportation sector are a result of a three-legged stool: fuel types, vehicle fuel efficiency, and vehicle miles travelled (VMT). While there is a substantial body of literature that examines the connection between the built environment and total VMT, few studies have focused on the impacts of the street environment on fuel consumption rate. Our research applied structural equation modeling to examine how driving behaviors and fuel efficiency respond to different street environments. We used a rich naturalistic driving dataset that recorded detailed driving patterns of 108 drivers randomly selected from the Southeast Michigan region. The results show that, some features of compact streets such as lower speed limit, higher intersection density, and higher employment density are associated with lower driving speed, more speed changes, and lower fuel efficiency; however, other features such as higher population density and higher density of pedestrian-scale retails improve fuel efficiency. The aim of our study is to gain further understanding of energy and environmental outcomes of the urban areas and the roadway infrastructure we plan, design, and build and to better inform policy decisions concerned with sustainable transportation.
Keywords
Travel; Consumption; Emissions; Cities; Energy; Street Environments; Fuel Efficiency; Structural Equation Modeling; Naturalistic Driving
Kang, Bumjoon; Scully, Jason Y.; Stewart, Orion; Hurvitz, Philip M.; Moudon, Anne V. (2015). Split-Match-Aggregate (SMA) Algorithm: Integrating Sidewalk Data with Transportation Network Data in GIS. International Journal Of Geographical Information Science, 29(3), 440 – 453.
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Abstract
Sidewalk geodata are essential to understand walking behavior. However, such geodata are scarce, only available at the local jurisdiction and not at the regional level. If they exist, the data are stored in geometric representational formats without network characteristics such as sidewalk connectivity and completeness. This article presents the Split-Match-Aggregate (SMA) algorithm, which automatically conflates sidewalk information from secondary geometric sidewalk data to existing street network data. The algorithm uses three parameters to determine geometric relationships between sidewalk and street segments: the distance between streets and sidewalk segments; the angle between sidewalk and street segments; and the difference between the lengths of matched sidewalk and street segments. The SMA algorithm was applied in urban King County, WA, to 13 jurisdictions' secondary sidewalk geodata. Parameter values were determined based on agreement rates between results obtained from 72 pre-specified parameter combinations and those of a trained geographic information systems (GIS) analyst using a randomly selected 5% of the 79,928 street segments as a parameter-development sample. The algorithm performed best when the distances between sidewalk and street segments were 12m or less, their angles were 25 degrees or less, and the tolerance was set to 18m, showing an excellent agreement rate of 96.5%. The SMA algorithm was applied to classify sidewalks in the entire study area and it successfully updated sidewalk coverage information on the existing regional-level street network data. The algorithm can be applied for conflating attributes between associated, but geometrically misaligned line data sets in GIS.
Keywords
Geodatabases; Sidewalks; Algorithms; Pedestrians; Digital Mapping; Algorithm; Gis; Pedestrian Network Data; Polyline Conflation; Sidewalk; Built Environment; Physical-activity; Mode Choice; Urban Form; Land-use; Travel; Generation; Walking
Baek, So-Ra; Moudon, Anne Vernez; Saelens, Brian E.; Kang, Bumjoon; Hurvitz, Philip M.; Bae, Chang-hee Christine. (2016). Comparisons of Physical Activity and Walking between Korean Immigrant and White Women in King County, WA. Journal Of Immigrant & Minority Health, 18(6), 1541 – 1546.
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Abstract
Immigrant and minority women are less physically active than White women particularly during leisure time. However, prior research demonstrates that reported household physical activity (PA) and non-leisure time walking/biking were higher among the former. Using accelerometers, GPS, and travel logs, transport-related, home-based, and leisure time PA were measured objectively for 7 days from a convenience sample of 60 first-generation Korean immigrant women and 69 matched White women from the Travel Assessment and Community Project in King County, Washington. Time spent in total PA, walking, and home-based PA was higher among Whites than Korean immigrants regardless of PA type or location. 58 % of the White women but only 20 % of the Korean women met CDC's PA recommendations. Socio-economic status, psychosocial factors, and participants' neighborhood built environmental factors failed to account for the observed PA differences between these groups.
Keywords
Accelerometer; Gps; Korean Immigrant Women; Objective Measures; Physical Activity; Walking; White Women; Nonleisure Time; Leisure-time; Environment; Transportation; Adults; Women; Socioeconomic Status; Time Use; Home Based; Environmental Aspects; Economic Status; Immigrants; Leisure; Socioeconomic Factors; Bicycles; Psychosocial Factors; Comparative Analysis; Minority & Ethnic Groups; Physical Fitness; Regression Analysis; Accelerometers; Travel; Traveltime; Environmental Factors; Recreation; Neighborhoods; Hispanic Americans; Global Positioning Systems--gps; Social Support; Noncitizens; Data Collection; Asian Americans; Psychological Aspects; Households; White People; Asian People; King County Washington; United States--us
Hashemloo, Alireza; Inanici, Mehlika; Meek, Christopher. (2016). Glareshade: A Visual Comfort-Based Approach to Occupant-Centric Shading Systems. Journal Of Building Performance Simulation, 9(4), 351 – 365.
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Abstract
This paper presents a novel method for designing of an occupant-centric shading algorithm that utilizes visual comfort metric as the form-generating criteria. Based on the premise of previous studies that demonstrate glare as the most important factor for operating shading devices, GlareShade is introduced as a simulation-based shading methodology driven by occupant's visual comfort. GlareShade not only responds to changing outdoor conditions such as the movement of the sun and the variation of cloud cover, but it also accounts for building specific local conditions. GlareShade draws its strength and flexibility from an occupant-centric approach that is based on the visual field of view of each occupant as the occupant is performing common visual tasks in a given environment, and the developed shading system is linked to a distributed sensing network of multiple occupants. ShadeFan is demonstrated as a proof-of-concept dynamic shading system utilizing the GlareShade method.
Keywords
Control Strategies; Design Tool; Daylight; Patterns; Offices; Blinds; Model; Occupant-centric Shading System; Glare; Daylighting; Visual Comfort
Oshima, Ken Tadashi. (2016). Rediscovering Japanese Urban Space in a World Context. Journal Of Urban History, 42(3), 623 – 633.
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Abstract
Counter to the rise of the modern metropolis in Japan in the era of high-speed growth following World War II, a movement to embrace elements of traditional townscapes that had been lost as rational urban planning took hold from the mid-1950s to the mid-1970s. During this period, the realities of large-scale urban development and increasing urban problems would eventually expose the limitations of functional planning and the need to preserve traditional structures and townscapes. While architects like Bruno Taut had praised the virtues of the farmhouse villages at Shirakawago in the 1930s and Yoshida Tetsur presented traditional Japanese architecture to an international audience as contemporary design before World War II, among others, the discourse subsequently shifted from Japanese objects and structures to urban space in the postwar period. This discourse on Japanese urban space would lead to the publication of Nihon no toshi kukan (Japanese Urban Space) in 1963 (1968 as a book) that presented the work of the Toshi dezain kenkyutai (Urban Design Research Group) including Isozaki Arata (1931-) and architectural historian It Teiji (1922-2010). This article analyzes the origins and implications of this work through a plethora of subsequent design surveys throughout Japan and other trajectories of research and design of Japanese urban space from the 1960s to the present.
Keywords
Japanese Urban Space; Urban Landscape; Serial Vision; Imageability; Design Survey