Dyson, Karen; Dawwas, Emad; Poulton Kamakura, Renata; Alberti, Marina; Fuentes, Tracy L. (2023). Say Where You Sample: Increasing Site Selection Transparency in Urban Ecology. Ecosphere, 14(3).
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Abstract
Urban ecological studies have the potential to expand our understanding of socioecological systems beyond that of an individual city or region. Cross-comparative empirical work and synthesis are imperative to develop a general urban ecological theory. This can be achieved only if studies are replicable and generalizable. Transparency in methods reporting facilitates generalizability and replicability by documenting the decisions scientists make during the various steps of research design; this is particularly true for sampling design and selection because of their impact on both internal and external validity and the potential to unintentionally introduce bias. Three interdependent aspects of sample design are study sample selection (e.g., specific organisms, soils, or water), sample specification (measurement of specific variable of interest), and site selection (locations sampled). Of these, documentation of site selection—the where component of sample design—is underrepresented in the urban ecology literature. Using a stratified random sample of 158 papers from 12 major urban ecology journals, we investigated how researchers selected study sites in urban ecosystems and evaluated whether their site selection methods were transparent. We extracted data from these papers using a 50-question, theory-based questionnaire and a multiple-reviewer approach. Our sample represented almost 45 years of urban ecology research across 40 different countries. We found that more than 80% of the papers we read were not transparent in their site selection methodology. We do not believe site selection methods are replicable for 70% of the papers read. Key weaknesses include incomplete descriptions of populations and sampling frames, urban gradients, sample selection methods, and property access. Low transparency in reporting the where methodology limits urban ecologists' ability to assess the internal and external validity of studies' findings and to replicate published studies; it also limits the generalizability of existing studies. The challenges of low transparency are particularly relevant in urban ecology, a field where standard protocols for site selection and delineation are still being developed. These limitations interfere with the fields' ability to build theory and inform policy. We conclude by offering a set of recommendations to increase transparency, replicability, and generalizability.
Keywords
external validity, field ecology, generalizability, internal validity, replication, reproducibility, sampling design, site selection, theory building, transparency
Choi, Kunhee, Bae, Junseo, Yin, Yangtian, and Lee, Hyun Woo. (2014). ACT²: Time–Cost Tradeoffs from Alternative Contracting Methods. Journal of Management in Engineering, 37(1).
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Abstract
Incentive/disincentive (I/D) and cost-plus-time (A+B) are two of the most widely used alternative contracting methods (ACMs) for accelerating the construction of highway infrastructure improvement projects. However, little is known about the effects of trade-offs in terms of project schedule and cost performance. This study addresses this problem by creating and testing a stochastic decision support model called accelerated alternative contracting cost-time trade-off (ACT2). This model was developed by a second-order polynomial regression analysis and validated by the predicted error sum of square statistic and paired comparison tests. The results of a descriptive trend analysis based on a rich set of high-confidence project data show that I/D is effective at reducing project duration but results in higher cost compared to pure A+B and conventional methods. This cost-time trade-off effect was confirmed by the ACT2 model, which determines the level of cost-time trade-off for different ACMs. This study will help state transportation agencies promote more effective application of ACMs by providing data-driven performance benchmarking results when evaluating competing acceleration strategies and techniques.
Keywords
Errors (statistics), Project management, Benefit cost ratios, Regression analysis, Construction costs, Infrastructure construction, Contracts and subcontracts, Construction methods
Kim, Yong-Woo, and 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
Organizations, Managers, Structural models, Scheduling, Structural reliability, Construction management, Human and behavioral factors, Resource allocation
Wang, Lan, Kaichen Zhou, Surong Zhang, Anne Vernez Moudon, Jinfeng Wang, Yong-Guan Zhu, Wenyao Sun, Jianfeng Lin, Chao Tian, and Miao Liu. 2023. “Designing Bike-Friendly Cities: Interactive Effects of Built Environment Factors on Cycling.” SSRN Electronic Journal.
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Abstract
Geographical detector models facilitate a comprehensive approach to urban Design. • Interaction detector measures combined effects of the built environment on Cycling. • Street network centrality has the largest explanatory power on cycling. • A sense of enclosure defined by streetscape elements encourages cycling. Designing bike-friendly cities could promote health and mitigate climate change. Most studies of the association between the built environment and cycling used the "5Ds" framework and linear modeling. However, the built environment exerts complex influences on travel behavior. To better inform urban design for cycling, this study employed geographical detector models that quantify the explanatory power of individual and interactively paired built environment factors on bike-sharing. Data came from 6.5 million bike-sharing orders in Shanghai. Expectedly, we found that street network centrality and important facilities like supermarkets and libraries have the greatest independent and interactive effects. More surprisingly, streetscape elements, including sky view and building frontage, offered significantly higher explanatory power when paired with each other or with street network centrality and important facilities. By identifying the overlooked interactive effects of urban environment factors, the study provides guidance for urban designers to consider combinations of factors that effectively promote cycling. [ABSTRACT FROM AUTHOR]
Keywords
Bike-friendly city; Cycling; Street view images; Urban design
Chen, Chen; Koll, Charles; Wang, Haizhong; Lindell, Michael K . 2023. “An Interdisciplinary Agent-Based Evacuation Model: Integrating the Natural Environment, Built Environment, and Social System for Community Preparedness and Resilience.” Natural Hazards and Earth System Sciences 23 (2).
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Abstract
Previous tsunami evacuation simulations have mostly been based on arbitrary assumptions or inputs adapted from non-emergency situations, but a few studies have used empirical behavior data. This study bridges this gap by integrating empirical decision data from surveys on local evacuation expectations and evacuation drills into an agent-based model of evacuation behavior for two Cascadia subduction zone (CSZ) communities that would be inundated within 20–40 min after a CSZ earthquake. The model also considers the impacts of liquefaction and landslides from the earthquake on tsunami evacuation. Furthermore, we integrate the slope-speed component from least-cost distance to build the simulation model that better represents the complex nature of evacuations. The simulation results indicate that milling time and the evacuation participation rate have significant nonlinear impacts on tsunami mortality estimates. When people walk faster than 1 m s -1 , evacuation by foot is more effective because it avoids traffic congestion when driving. We also find that evacuation results are more sensitive to walking speed, milling time, evacuation participation, and choosing the closest safe location than to other behavioral variables. Minimum tsunami mortality results from maximizing the evacuation participation rate, minimizing milling time, and choosing the closest safe destination outside of the inundation zone. This study's comparison of the agent-based model and the beat-the-wave (BtW) model finds consistency between the two models' results. By integrating the natural system, built environment, and social system, this interdisciplinary model incorporates substantial aspects of the real world into the multi-hazard agent-based platform. This model provides a unique opportunity for local authorities to prioritize their resources for hazard education, community disaster preparedness, and resilience plans. [ABSTRACT FROM AUTHOR]
Lindell, Michael K., Meen Chel Jung, Carla S. Prater, and Donald H. House. 2023. “US Pacific Coast Communities’ Past Preparedness and Preparedness Intentions for Cascadia Subduction Zone Tsunamis.” International Journal of Disaster Risk Reduction 84.
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Abstract
This study examined tsunami awareness and preparedness by 225 respondents in three communities exposed to Cascadia Subduction Zone (CSZ) tsunamis. Some participants viewed a tsunami brochure, but all participants reported their degree of information sufficiency about tsunamis and protective actions to take when a tsunami threatens, expected warning sources for local and distant tsunamis, past preparedness actions and preparedness intentions, tsunami experience, past tsunami information, perceived tsunami zone, and demographic characteristics. In addition to the results showing that the brochure had a significant positive effect on tsunami information sufficiency and expected warning sources, the latter two variables affected intentions to engage in future preparedness actions. In addition, tsunami experience, past tsunami infor-mation, and past preparedness also affected these variables. Although psychological responses were significantly related to preparedness intentions, they were not related to hypothesized antecedent variables-tsunami experience, past preparedness, past information, and de-mographic characteristics. The data suggest that emergency managers can promote tsunami hazard education by distributing comprehensive tsunami brochures, but should also work with local news media to direct CSZ residents to agency web sites where they can access additional information about tsunami hazard, expected warning sources, appropriate preparedness, and response actions.
Keywords
Cascadia subduction zone tsunamis; Risk communication; Tsunami hazard awareness; Tsunami preparedness
Min, Yohan, Lee, Hyun Woo, & Hurvitz, Philip M. (2023). Clean Energy Justice: Different Adoption Characteristics of Underserved Communities in Rooftop Solar and Electric Vehicle Chargers in Seattle. Energy Research & Social Science, 96.
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Abstract
Concerns over global climate change have led to energy transition to clean energy systems with the development of various clean energy policies. However, social equity issues have emerged in association with the rapid transition of energy systems related to distributed energy resources (DERs), evidenced by disparities in clean energy access. While most existing studies have focused on several variables impacting the adoption of DERs, there is a dearth of studies concerning distributional and recognition justice specifically aimed at investigating: (1) which DER adoption variable is the most important among several variables identified in the literature; and (2) how adoption patterns vary by technologies and communities. The objective of the present study is to answer the two questions by examining the geographic distribution of rooftop solar and electric vehicle (EV) chargers and the related community attributes. Also, the study involves identifying latent variables by addressing inter-correlations among several adoption determinants. The results show that rooftop solar and EV charger adoptions in Seattle present disparities associated with geographic locations and community attributes. In particular, housing variables are the main indicators for rooftop solar adoption and even stronger in communities with low adoption rates. EV charger adoptions are strongly associated with economic variables. Furthermore, spatial inequality of rooftop solar adoption is higher than that of EV charger adoption. The study suggests housing-related support may increase the adoption of both technologies, particularly in communities with low adoption rates. Considering that the installations of rooftop solar and EV chargers were concentrated in particular communities, the study results imply that policies aimed at increasing the adoption of DERs should be tailored to local community characteristics.
Min, Yohan; Lee, Hyun Woo. (2023). Characterization of Vulnerable Communities in Terms of the Benefits and Burdens of the Energy Transition in Pacific Northwest Cities. Journal of Cleaner Production.
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Abstract
Energy transition to renewable sources has occurred along with the development of various clean energy policies aimed at decarbonization and electrification. However, the transition can inadvertently lead to social inequity resulting in increasing burdens on vulnerable communities. Although many studies have tried to define and identify vulnerable communities, there has been no study specifically aimed at characterizing vulnerable communities in terms of the benefits and burdens of such energy transition. In response, the objective of this study is to characterize vulnerable communities by examining rooftop solar adoption and energy expenditure using spatial and mixed-effect models. Rooftop solar adoption operationalizes energy resilience and benefits, and energy expenditure operationalizes energy dependence and burdens of the transition. The study also investigates the link between rooftop solar adoption and energy expenditure by considering city-level variability in three Pacific Northwest cities. The results show that Bellevue has 50.4% less rooftop solar adoption than Portland, while Portland has 16.1% or $223 more energy expenditure than Seattle. On average, an increase in annual energy expenditure of $431 is associated with 29% increase in rooftop solar adoption, specifically Bellevue, Seattle, and Portland by 21.4%, 39.1%, and 26.2%, respectively, but not vice versa. Furthermore, the group of communities more vulnerable in housing attributes has 15.2% less rooftop solar adoption than the group of more vulnerable communities in socioeconomic attributes. In addition, the city centers, commercial areas, or mid-rise and high-rise zones are found to have lower rooftop solar adoption and energy expenditure than other areas. The results suggest that policymakers should consider between-city variability when identifying vulnerable communities. Policies should also be tailored to local communities based on their attributes as communities with similar attributes tend to cluster together. Furthermore, policymakers should focus more on housing and built environment attributes to promote resilient communities.
Hou, J. (2023). Seattle’s CHOP Guerrilla Garden as a “Thick” Space of Civil Resistance. Local Environment, 28(2), 189–202.
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Abstract
More than just everyday acts of appropriation, guerrilla gardens have appeared in a growing number of civic protests. During Seattle’s Capitol Hill Occupied Protest (CHOP) in 2020, a guerrilla garden was featured prominently within the six-block area taken over by protesters following a standoff with the Seattle Police. Through informal and semi-structured interviews with the garden leaders, volunteers, protesters, and neighbours who lived near the site, this study examines the garden's role and significance during the month-long protest. Findings suggested that the CHOP garden provided opportunities for social interactions among protesters as well as non-protesters. Through expanded engagement, the garden brought a wider range of individuals to the protest site. With its ability to engage broader participation, the garden helped mobilise additional human and material resources for the movement. Furthermore, the garden functioned as a place of learning that deepened the meanings and narrative of the movement. It also served as a place of refuge and relief during the tense occupation. Lastly, the social networks and relationships that emerged from the garden serve as a vehicle for sustaining the movement beyond the protest. As a place that facilitated these multilayered processes, these findings suggest that the CHOP Garden functioned as a “thick” space of civil resistance. The notion of thick space highlights the importance of specific spatial practices that can contribute significantly to the transformative outcomes of social movements.
Keywords
Guerrilla garden; protest; civil resistance; thick space; CHOP
Wu, Shuang, Abramson, Daniel B., & Zhong, Bo. (2022). Digital Governance in Rural Chengdu, China: Its Potential for Social-ecological Resilience. Frontiers in Sustainable Cities, 4.
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Abstract
In this study, we echo the call from the UN to interpret Sustainable Development Goals (SDGs) in their regional context—in this case, the linpan (wooded lot) landscape of the Chengdu Plain, in Sichuan, China, where the shocks and stresses of recent, rapid administrative-economic urbanization are testing the resilience of some of the world's most sustainably productive and long- and densely-settled agrarian environments. In recent years, fine-grained information and communications technology (ICT) governance tools in Chengdu, such as “grid management”, present opportunities to sustain and scale up the collection of data necessary to validate and refine indicators of landscape resilience, and use them to regulate development, in accordance with SDG goal 11 to enhance legislation, governance, and capacity via information gathering and sharing. ICT-based governance in combination with traditional place-based knowledge can play a critical role in ensuring the resilience of urban-rural co-development. To realize this potential, however, ICT-enabled governance needs to incorporate greater transparency and more local feedback loops and enable greater participation from older farmers and women, to inform household and community-level land-use choices and initiatives. It also needs to link regulatory functions with marketing and pricing functions so that farmers may benefit from the sustainable practices they are encouraged to adopt.