Lee, Wonil; Migliaccio, Giovanni C.; Lin, Ken-Yu; Seto, Edmund Y. W. (2020). Workforce Development: Understanding Task-Level Job Demands-Resources, Burnout, and Performance in Unskilled Construction Workers. Safety Science, 123.
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Abstract
This study examines how task demands and personal resources affect unskilled construction worker productivity and safety performance. It extends the job demands-resources (JD-R) burnout model to show how job characteristics interact with burnout to influence performance. A modified model was designed to measure burnout, with exhaustion and disengagement among unskilled construction workers taken into consideration. An observational study was conducted in a laboratory environment to test the research hypotheses and assess the prediction accuracies of outcome constructs. Twenty-two subjects participated in multiple experiments designed to expose them to varying levels of task-demands and to record their personal resources as they performed common construction material-handling tasks. Specifically, both surveys and physiological measurements using wearable sensors were used to operationalize the model constructs. Moreover, partial least squares structural equation modeling was applied to analyze data collected at the task and individual levels. Exhaustion and disengagement exhibited different relationships with productivity and safety performance outcomes as measured by unit rate productivity and ergonomic behavior, respectively. Subjects with high burnout and high engagement showed high productivity but low safety performance. Thus, exhausted workers stand a greater chance of failing to comply with safety. As the sample and the task performed in the experiment do not cover the experience and trade of all construction workers, our findings are limited in their application to entry-level and unskilled workers, whose work is mainly manual material-handling tasks.
Keywords
Construction Workers; Structural Equation Modeling; Job Descriptions; Labor Productivity; Labor Supply; Burnout; Job Demand-resources Model; Partial Least Squares Structural Equation Modeling; Productivity; Safety; Wearable Sensors; Biomechanics; Construction Industry; Ergonomics; Occupational Health; Occupational Safety; Occupational Stress; Personnel; Statistical Analysis; Workforce Development; Understanding Task-level Job Demands-resources; Unskilled Construction Workers; Task Demands; Personal Resources; Unskilled Construction Worker Productivity; Job Demands-resources Burnout Model; Job Characteristics Interact; Exhaustion; Disengagement; Outcome Constructs; Varying Levels; Task-demands; Common Construction Material-handling Tasks; Physiological Measurements; Model Constructs; Individual Levels; Unit Rate Productivity; High Burnout; Low Safety Performance; Exhausted Workers; Entry-level; Unskilled Workers; Manual Material-handling Tasks; Heart-rate-variability; Labor Productivity Trends; Physiological Demands; Emotional Exhaustion; Safety Climate; Role Stress; Engagement; Fatigue; Workload; Task Analysis; Workforce; Level (quantity); Construction Materials; Personnel Management; Materials Handling; Multivariate Statistical Analysis
Shang, Luming; Aziz, Ahmed M. Abdel. (2020). Stackelberg Game Theory-Based Optimization Model for Design of Payment Mechanism in Performance-Based PPPs. Journal Of Construction Engineering And Management, 146(4).
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Abstract
Payment mechanisms lie at the heart of public-private partnership (PPP) contracts. A good design of the payment mechanism should consider the owner's goals in the project, allocate risks appropriately to stakeholders, and assure satisfactory performance by providing reasonable compensation to the private developer. This paper proposes a Stackelberg game theory-based model to assist public agencies in designing payment mechanisms for PPP transportation projects. The interests of both public and private sectors are considered and reflected by a bilevel objective function. The model aims to search for solutions that maximize a project's overall performance for the sake of social welfare while simultaneously maximizing return for the sake of private investment. A variable elimination method and genetic algorithm are used to solve the optimization model. A case study based on a real PPP project is discussed to validate the effectiveness of the proposed model. The solutions provided by the model reveal that the optimal payment mechanism structure could be established such that it would satisfy owners' requirements for overall project performance while optimizing project total payments to contractors.
Keywords
Construction Industry; Contracts; Financial Management; Game Theory; Genetic Algorithms; Investment; Optimisation; Organisational Aspects; Project Management; Public Administration; Transportation; Public-private Partnership Contracts; Good Design; Private Developer; Stackelberg Game Theory-based Model; Ppp Transportation Projects; Public Sectors; Private Sectors; Private Investment; Ppp Project; Optimal Payment Mechanism Structure; Project Performance; Project Total Payments; Stackelberg Game Theory-based Optimization Model; Performance-based Ppps; Public-private Partnerships; Analytic Hierarchy Process; Weighted Sum Method; Multiobjective Optimization; Algorithm; Incentives; Projects; Network; Success; Branch
Chalana, Manish. (2021). Whither the “Hindoo Invasion”? South Asians in the Pacific Northwest of the United States, 1907-1930. International Journal Of Regional & Local History, 16(1), 14 – 38.
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Abstract
The first decade of the twentieth century saw several thousand men migrate from India to the North American West Coast. While most settled in British Columbia or California, a smaller number moved to the US Pacific Northwest states of Washington and Oregon. A series of violent riots in 1907-8 drove many from the region. The basic contours of this population in the region after this time remain unclear. I uncover evidence that Indians persisted for a longer time period, and in more varied locations and occupations than some previous research suggests, but that ultimately violent exclusion led them to disappear almost entirely from the region. I investigate the conditions in which these men lived and toiled, and the ways in which they were viewed by the larger society, particularly in terms of evolving concepts of race and assimilation. [ABSTRACT FROM AUTHOR]; Copyright of International Journal of Regional & Local History is the property of Taylor & Francis Ltd 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
Immigration; Indians; Oregon; Pacific Northwest; Punjabis; Sikh; South Asians; Washington
Lin, Brenda B.; Ossola, Alessandro; Alberti, Marina; Andersson, Erik; Bai, Xuemei; Dobbs, Cynnamon; Elmqvist, Thomas; Evans, Karl L.; Frantzeskaki, Niki; Fuller, Richard A.; Gaston, Kevin J.; Haase, Dagmar; Jim, Chi Yung; Konijnendijk, Cecil; Nagendra, Harini; Niemela, Jari; Mcphearson, Timon; Moomaw, William R.; Parnell, Susan; Pataki, Diane; Ripple, William J.; Tan, Puay Yok. (2021). Integrating Solutions to Adapt Cities for Climate Change. Lancet Planetary Health, 5(7), E479 – E486.
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Abstract
Record climate extremes are reducing urban liveability, compounding inequality, and threatening infrastructure. Adaptation measures that integrate technological, nature-based, and social solutions can provide multiple co-benefits to address complex socioecological issues in cities while increasing resilience to potential impacts. However, there remain many challenges to developing and implementing integrated solutions. In this Viewpoint, we consider the value of integrating across the three solution sets, the challenges and potential enablers for integrating solution sets, and present examples of challenges and adopted solutions in three cities with different urban contexts and climates (Freiburg, Germany; Durban, South Africa; and Singapore). We conclude with a discussion of research directions and provide a road map to identify the actions that enable successful implementation of integrated climate solutions. We highlight the need for more systematic research that targets enabling environments for integration; achieving integrated solutions in different contexts to avoid maladaptation; simultaneously improving liveability, sustainability, and equality; and replicating via transfer and scale-up of local solutions. Cities in systematically disadvantaged countries (sometimes referred to as the Global South) are central to future urban development and must be prioritised. Helping decision makers and communities understand the potential opportunities associated with integrated solutions for climate change will encourage urgent and deliberate strides towards adapting cities to the dynamic climate reality.
Keywords
Urban; Resilience; Energy; Water; Transformations; Sustainability; Opportunities; Challenges; Mitigation; Knowledge
Xiang, Wei-qi; Yang, Xiao-hua; Li, Yu-qi. (2021). A Set Pair Analysis Model for Suitability Evaluation of Human Settlement Environment. Thermal Science, 25(3B), 2109 – 2116.
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Abstract
The human settlement environment is a dynamic subsystem where people live and produce in the social system. This paper aims at evaluating comprehensively the suitability state of a given human settlement environment in a certain time and space and its evolutionary trend, the set pair analysis theory and its connection numbers are introduced into the suitability evaluation, and the set of human settlements is established. The set pair analysis model based on partial connection number is used to assess the suitability status and the development trend of human settlements in Guizhou Province from 2014 to 2017. The result shows that the set pair analysis model has the features of convenience, impersonality and good feasibility.
Keywords
Human Ecology; Human Settlements; Number Theory; Social Systems; Guizhou Sheng (china); Human Settlement Environment; Partial Connection Number; Set Pair Analysis; Suitability Evaluation
El-Anwar, Omar; El-Rayes, Khaled; Elnashai, Amr. (2010). Maximizing Temporary Housing Safety after Natural Disasters. Journal Of Infrastructure Systems, 16(2), 138 – 148.
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Abstract
In the aftermath of large-scale natural disasters, emergency management organizations are expected to provide safe temporary housing for a large number of displaced families and to ensure that these housing arrangements are not located in hazardous areas. Potential postdisaster hazards can take many forms such as earthquake aftershocks, landslides, postearthquake soil liquefaction, flooding, hazardous material releases, etc. This paper presents the development of a multiobjective optimization methodology to support decision-makers in emergency management organizations in optimizing postdisaster temporary housing arrangements. The developed methodology incorporates (1) a safety model to measure and quantify temporary housing safety in the presence of multiple potential postdisaster hazards; (2) a cost model to minimize total public expenditures on temporary housing; and (3) a multiobjective optimization model to simultaneously maximize temporary housing safety and minimize public expenditures on temporary housing. An application to a large region is presented to illustrate the use of the models and demonstrate their capabilities in optimizing postdisaster temporary housing arrangements.
Keywords
Earthquake; Landslides; Optimization; Temporary Housing; Postdisaster Hazards; Housing Safety; Postdisaster Recovery
Hutyra, Lucy R.; Yoon, Byungman; Hepinstall-Cymerman, Jeffrey; Alberti, Marina. (2011). Carbon Consequences of Land Cover Change and Expansion of Urban Lands: A Case Study in the Seattle Metropolitan Region. Landscape And Urban Planning, 103(1), 83 – 93.
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Abstract
Understanding the role humans play in modifying ecosystems through changing land cover is central to addressing our current and emerging environmental challenges. In particular, the consequences of urban growth and land cover change on terrestrial carbon budgets is a growing issue for our rapidly urbanizing planet. Using the lowland Seattle Statistical Metropolitan Area (MSA) region as a case study, this paper explores the consequences of the past land cover changes on vegetative carbon stocks with a combination of direct field measurements and a time series of remote sensing data. Between 1986 and 2007, the amount of urban land cover within the lowland Seattle MSA more than doubled, from 1316 km(2) to 2798 km(2), respectively. Virtually all of the urban expansion was at the expense of forests with the forested area declining from 4472 km(2) in 1986 to 2878 km(2) in 2007. The annual mean rate of urban land cover expansion was 1 +/- 0.6% year(-1). We estimate that the impact of these regional land cover changes on aboveground carbon stocks was an average loss of 1.2 Mg C ha(-1) yr(-1) in vegetative carbon stocks. These carbon losses from urban expansion correspond to nearly 15% of the lowland regional fossil fuel emissions making it an important, albeit typically overlooked, term in regional carbon emissions budgets. As we plan for future urban growth and strive for more ecologically sustainable cities, it is critical that we understand the past patterns and consequences of urban development to inform future land development and conservation strategies. (C) 2011 Elsevier B.V. All rights reserved.
Keywords
Sprawl; Growth; Carbon Cycle; Emissions; Land Cover; Urbanization; Seattle; Vegetation; Carbon; Carbon Sinks; Case Studies; Cities; Ecosystems; Forests; Fossil Fuels; Humans; Land Use; Planning; Remote Sensing; Time Series Analysis
Lin, K. Y.; Levan, A.; Dossick, C. S. (2012). Teaching Life-Cycle Thinking in Construction Materials and Methods: Evaluation of and Deployment Strategies for Life-Cycle Assessment in Construction Engineering and Management Education. Journal Of Professional Issues In Engineering Education And Practice, 138(3), 163 – 170.
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Keywords
Sustainability; Design
El-Anwar, Omar. (2013). Advancing Optimization of Hybrid Housing Development Plans Following Disasters: Achieving Computational Robustness, Effectiveness, and Efficiency. Journal Of Computing In Civil Engineering, 27(4), 358 – 369.
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Abstract
Following disasters, displaced families often face significant challenges to move from temporary to permanent housing. The Federal Emergency Management Agency is exploring alternative housing pilot programs to evaluate the possibility of providing quickly deployable, affordable housing that can serve both as temporary and permanent housing. Because of the complexities and costs associated with these programs, it is impractical to assume that accelerated permanent housing can fully replace the need for traditional temporary housing, especially in cases of large-scale displacements. A novel methodology was developed to evaluate the socioeconomic benefits of candidate configurations of hybrid housing plans, which incorporates both temporary and accelerated permanent housing developments. This paper presents the computational implementation and performance analysis of this novel methodology to offer a practical decision-support tool to emergency planners. To this end, genetic algorithms and integer-programming optimization models are formulated, and their performances are analyzed based on their effectiveness, efficiency, and robustness. In lieu of developing the integer-programming model, the paper also presents a linear formulation that overcomes the need to use logical operations to model fixed and variable cost components for developing housing projects. Results show the superior performance of integer programming, whereas genetic algorithms offer higher modeling flexibility.
Keywords
Decision Support Systems; Emergency Management; Genetic Algorithms; Integer Programming; Advancing Optimization; Hybrid Housing Development Plans Following Disasters; Achieving Computational Robustness; Achieving Computational Effectiveness; Achieving Computational Efficiency; Federal Emergency Management Agency; Housing Pilot Programs; Temporary Housing; Permanent Housing Developments; Decision-support Tool; Emergency Planners; Integer-programming Optimization Models; Logical Operations; Optimization; Disasters; Housing; Social Factors; Economic Factors; Computation; Hybrid Methods; Disaster Recovery; Accelerated Permanent Housing; Socioeconomic Welfare; Robustness; Effectiveness; Computational Efficiency; 0
Aggarwal, Anju; Cook, Andrea J.; Jiao, Junfeng; Seguin, Rebecca A.; Moudon, Anne Vernez; Hurvitz, Philip M.; Drewnowski, Adam. (2014). Access to Supermarkets and Fruit and Vegetable Consumption. American Journal Of Public Health, 104(5), 917 – 923.
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Abstract
Objectives. We examined whether supermarket choice, conceptualized as a proxy for underlying personal factors, would better predict access to supermarkets and fruit and vegetable consumption than mere physical proximity. Methods. The Seattle Obesity Study geocoded respondents' home addresses and locations of their primary supermarkets. Primary supermarkets were stratified into low, medium, and high cost according to the market basket cost of 100 foods. Data on fruit and vegetable consumption were obtained during telephone surveys. Linear regressions examined associations between physical proximity to primary supermarkets, supermarket choice, and fruit and vegetable consumption. Descriptive analyses examined whether supermarket choice outweighed physical proximity among lower-income and vulnerable groups. Results. Only one third of the respondents shopped at their nearest supermarket for their primary food supply. Those who shopped at low-cost supermarkets were more likely to travel beyond their nearest supermarket. Fruit and vegetable consumption was not associated with physical distance but, with supermarket choice, after adjusting for covariates. Conclusions. Mere physical distance may not be the most salient variable to reflect access to supermarkets, particularly among those who shop by car. Studies on food environments need to focus beyond neighborhood geographic boundaries to capture actual food shopping behaviors.
Keywords
Confidence Intervals; Correlation (statistics); Fruit; Geographic Information Systems; Ingestion; Multivariate Analysis; Population Geography; Questionnaires; Regression Analysis; Research Funding; Sales Personnel; Shopping; Travel; Vegetables; Predictive Validity; Cross-sectional Method; Statistical Models; Descriptive Statistics; Null Hypothesis; Washington (state); Local Food Environment; Diet Quality; Socioeconomic Position; Atherosclerosis Risk; Stores; Associations; Obesity; Adults; Availability; Communities