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Neurophysiological Testing for Assessing Construction Workers’ Task Performance at Virtual Height

Habibnezhad, Mahmoud; Puckett, Jay; Jebelli, Houtan; Karji, Ali; Fardhosseini, Mohammad Sadra; Asadi, Somayeh. (2020). Neurophysiological Testing for Assessing Construction Workers’ Task Performance at Virtual Height. Automation In Construction, 113.

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Abstract

Falling from heights is the primary cause of death and injuries at construction sites. As loss of balance has a fundamental effect on falling, it is important to understand postural regulation behavior during construction tasks at heights, especially those that require precise focus in an upright standing position (therefore, a dual-task demand on focus). Previous studies examined body sway during a quiet stance and dual tasks to understand latent factors affecting postural balance. Despite the success of these studies in discovering underlying factors, they lack a comprehensive analysis of a task's simultaneous cognitive load, postural sway, and visual depth. To address this limitation, this paper aims to examine construction workers' postural stability and task performance during the execution of visual construction tasks while standing upright on elevated platforms. To that end, two non-intrusive neurophysiological tests, a hand-steadiness task (HST) and a pursuit task (PT), were developed for construction tasks in a virtual environment (VE) as performance-based means to assess the cognitive function of workers at height. Workers' postural stability was measured by recording the mapped position of the Center of Pressure (COP) of the body on a posturography force plate, and the postural sway metrics subsequently calculated. A laboratory experiment was designed to collect postural and task performance data from 18 subjects performing the two batteries of tests in the virtual environment. The results demonstrated a significant decrease in the Root-Mean Square (RMS) of COP along the anterior-posterior axis during the Randomized Pursuit Task (RPT) and maximum body sway of the center of pressure (COP) in the mediolateral direction during both tests. Also, subjects exposed to high elevation predominately exhibit higher accuracy for RPT (P-value = 0.02) and lower accuracy for HST (P-value = 0.05). The results show that the combination of elevation-related visual depth and low-complexity dual tasks impairs task performance due to the elevation-induced visual perturbations and anxiety-driven motor responses. On the other hand, in the absence of visual depth at height, high task complexity surprisingly improves the pursuit tracking performance. As expected, during both tasks, alterations in postural control were manifested in the form of a body sway decrement as a compensatory postural strategy for accomplishing tasks at high elevation.

Keywords

Task Performance; Construction Workers; Test Design; Cognitive Load; Standing Position; Sitting Position; Neurophysiological Test; Postural Stability; Virtual Reality; Workers' Safety At Height; Fall-risk; Reaction-time; Fear; Real; Acrophobia; Balance; Safety

Evidence-Driven Sound Detection for Prenotification and Identification Of Construction Safety Hazards and Accidents

Lee, Yong-Cheol; Shariatfar, Moeid; Rashidi, Abbas; Lee, Hyun Woo. (2020). Evidence-Driven Sound Detection for Prenotification and Identification Of Construction Safety Hazards and Accidents. Automation In Construction, 113.

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Abstract

As the construction industry experiences a high rate of casualties and significant economic loss associated with accidents, safety has always been a primary concern. In response, several studies have attempted to develop new approaches and state-of-the-art technology for conducting autonomous safety surveillance of construction work zones such as vision-based monitoring. The current and proposed methods including human inspection, however, are limited to consistent and real-time monitoring and rapid event recognition of construction safety issues. In addition, the health and safety risks inherent in construction projects make it challenging for construction workers to be aware of possible safety risks and hazards according to daily planned work activities. To address the urgent demand of the industry to improve worker safety, this study involves the development of an audio-based event detection system to provide daily safety issues to laborers and through the rapid identification of construction accidents. As an evidence-driven approach, the proposed framework incorporates the occupational injury and illness manual data, consisting of historical construction accident data classified by types of sources and events, into an audio-based safety event detection framework. This evidence-driven framework integrated with a daily project schedule can automatically provide construction workers with prenotifications regarding safety hazards at a pertinent work zone as well as consistently contribute to enhanced construction safety monitoring by audio-based event detection. By using a machine learning algorithm, the framework can clearly categorize the narrowed-down sound training data according to a daily project schedule and dynamically restrict sound classification types in advance. The proposed framework is expected to contribute to an emerging knowledge base for integrating an automated safety surveillance system into occupational accident data, significantly improving the accuracy of audio-based event detection.

Keywords

Construction Projects; Occupational Hazards; Construction Workers; Construction; System Safety; Video Surveillance; Work-related Injuries; Audio-based Accident Recognition; Autonomous Safety Surveillance; Construction Safety; Evidence-driven Sound Event Detection; Accident Prevention; Accidents; Audio Acoustics; Classification (of Information); Construction Industry; Health Hazards; Health Risks; Knowledge Based Systems; Learning Algorithms; Losses; Machine Learning; Monitoring; Motion Compensation; Occupational Diseases; Steel Beams And Girders; Audio-based; Construction Accidents; Construction Work Zones; Historical Construction; Sound Event Detection; State-of-the-art Technology; Vision Based Monitoring; Algorithm; System

Impact of Energy Benchmarking and Disclosure Policy on Office Buildings

Shang, Luming; Lee, Hyun Woo; Dermisi, Sofia; Choe, Youngjun. (2020). Impact of Energy Benchmarking and Disclosure Policy on Office Buildings. Journal Of Cleaner Production, 250.

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Abstract

Building energy benchmarking policies require owners to publicly disclose their building's energy performance. In the US, the adoption of such policies is contributing to an increased awareness among tenants and buyers and is expected to motivate the owners of less efficient buildings to invest in energy efficiency improvements. However, there is a lack of studies specifically aimed at investigating the impact of such policies on office buildings among major cities through quantitative analyses. In response, this study evaluated the effectiveness of the benchmarking policy on energy efficiency improvements decision-making and on real estate performances, by applying two interrupted time series analyses to office buildings in downtown Chicago. The initial results indicate a lack of statistically strong evidence that the policy affected the annual vacancy trend of the energy efficient buildings (represented by ENERGY STAR labeled buildings). However, the use of interrupted time series in a more in-depth analysis shows that the policy is associated with a 6.7% decrease in vacancy among energy efficient buildings. The study proposed a method to quantitatively evaluate the impact of energy policies on the real estate performance of office buildings, and the result confirms the positive impact of energy-efficient retrofits on the real estate performance. The study findings support the reasoning behind the owners' decision in implementing energy efficiency improvements in their office buildings to remain competitive in the market. (C) 2019 Elsevier Ltd. All rights reserved.

Keywords

Office Buildings; Building Failures; Time Series Analysis; Real Property; Energy Consumption; Metropolis; Building Performance; Chicago (ill.); Building Energy Benchmarking And Disclosure Policies; Building Energy Efficiency; Time Series Modeling; Energy Star (program); Building Management Systems; Buildings (structures); Decision Making; Energy Conservation; Maintenance Engineering; Time Series; Disclosure Policy; Energy Benchmarking Policies; Building; Benchmarking Policy; Energy Efficiency Improvements Decision-making; Estate Performance; Energy Efficient Buildings; Energy Star; Energy Policies; Energy-efficient Retrofits; Interrupted Time-series; Regression; Behavior; Designs; Building Energy Benchmarking And; Disclosure Policies; Buildings; Cities; Energy Efficiency; Energy Policy; Markets; Quantitative Analysis; United States

Ancient and Current Resilience in the Chengdu Plain: Agropolitan Development Re-‘Revisited’

Abramson, Daniel B. (2020). Ancient and Current Resilience in the Chengdu Plain: Agropolitan Development Re-‘Revisited’. Urban Studies (sage Publications, Ltd.), 57(7), 1372 – 1397.

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Abstract

The Dujiangyan irrigation system, China's largest, is one of the world's most important examples of sustainable agropolitan development, maintained by a relatively decentralised system of governance that minimises bureaucratic oversight and depends on significant local autonomy at many scales down to the household. At its historic core in the Chengdu Plain, the system has supported over 2000 years of near-continuously stable urban culture, as well as some of the world's highest sustained long-term per-hectare productivity and diversity of grain and other crops, especially considering its high population density, forest cover, general biodiversity and flood management success. During the past decade, rapid urban expansion has turned the Chengdu Plain from a net grain exporter into a grain importer, and has radically transformed its productive functioning and distinctive scattered settlement pattern, reorganising much of the landscape into larger, corporately-managed farms, and more concentrated and infrastructure-intensive settlements of non-farming as well as farming households. Community-scale case studies of spatial-morphological and household socio-economic variants on the regional trend help to articulate what is at stake. Neither market-driven 'laissez-faire' rural development nor local state-driven spatial settlement consolidation and corporatisation of production seem to correlate well with important factors of resilience: landscape heterogeneity; crop diversity and food production; permaculture; and flexibility in household independence and choice of livelihood. Management of the irrigation system should be linked to community-based agricultural landscape preservation and productive dwelling, as sources of adaptive capacity crucial to the social-ecological resilience of the city-region, the nation and perhaps all humanity.

Keywords

Urbanization; Economies Of Agglomeration; Agricultural Ecology; Sustainability; Urban Planning; Land Use; China; Agglomeration/urbanisation; Agroecosystems; Environment/sustainability; History/heritage/memory; Redevelopment/regeneration; Cultivated Land; Countryside; Expansion; State; Rise; Modernization; Conservation; Integration; Earthquake; Agglomeration; Urbanisation; Environment; History; Heritage; Memory; Redevelopment; Regeneration; Population Density; Production; Farming; Agriculture; Decentralization; Autonomy; Food Production; Households; Landscape; Resilience; Rural Development; Food; Farms; Regional Development; Productivity; Economic Development; Case Studies; Agricultural Production; Biodiversity; Sustainable Development; Governance; Preservation; Crops; Flood Management; Irrigation; Permaculture; Radicalism; Socioeconomic Factors; Grain; Flexibility; Heterogeneity; Variants; Urban Areas; Irrigation Systems; Rural Communities; Bureaucracy; Landscape Preservation; Agricultural Land; Flood Control; Density; Infrastructure; Urban Sprawl; Livelihood; Farm Management; Rural Areas; Urban Farming; Settlement Patterns; Agribusiness; Market Economies

Blue Seattle: Immanent Ethics and Contemporary Urbanisation

Harris, Keith. (2020). Blue Seattle: Immanent Ethics and Contemporary Urbanisation. Area, 52(2), 273 – 281.

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Abstract

This paper asserts that critical investigations into the urbanisation process should consider the actually existing ethics of the process itself, without defaulting to transcendent normative principles. Grounded in an ontology of immanence, as presented in Deleuze and Guattari's (9) political philosophy, I argue that attention must be paid to the production and transformation of normativity. Using the redevelopment of the South Lake Union (SLU) neighbourhood of Seattle - (in)famously home to Amazon, but largely envisioned and developed by Paul Allen's investment and philanthropic organisation, Vulcan - as an analytical starting point, this paper sketches out a profile of the blue dimension of the genesis of Seattle's environmental ethic, from early efforts to reshape the region's hydrology and address water pollution in Lake Washington, through efforts by governmental bodies and Vulcan to protect water quality and salmon habitat, and on to a large-scale infrastructure project - the Elliott Bay Seawall replacement - that includes features to enhance biodiversity and ecological functioning in the nearshore environment. In tracking these movements, I identify the emergence of an explicitly post-anthropocentric ethic from what initially appears as an aesthetic concern, while also highlighting the ongoing complexification of an earlier engineering ethic that dates back to the earliest attempts by settlers to manage the natural environment.

Keywords

Water Pollution; Urbanization; Water Quality; Ethics; Political Philosophy; Home Ownership; Seattle (wash.); Blue Space; Deleuze And Guattari; Immanence; Post-anthropocentrism; Seattle; Allen, Paul, 1953-2018; Deleuze; Post-anthropocentrism

Community Response to Hurricane Threat: Estimates of Household Evacuation Preparation Time Distributions

Lindell, Michael K.; Sorensen, John H.; Baker, Earl J.; Lehman, William P. (2020). Community Response to Hurricane Threat: Estimates of Household Evacuation Preparation Time Distributions. Transportation Research Part D-transport And Environment, 85.

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Abstract

Household evacuation preparation time distributions are essential when computing evacuation time estimates (ETEs) for hurricanes with late intensification or late changing tracks. Although evacuation preparation times have been assessed by expected task completion times, actual task completion times, and departure delays, it is unknown if these methods produce similar results. Consequently, this study compares data from one survey assessing expected task completion times, three surveys assessing actual task completion times, and three surveys assessing departure delays after receiving a warning. In addition, this study seeks to identify variables that predict household evacuation preparation times. These analyses show that the three methods of assessing evacuation preparation times produce results that are somewhat different, but the differences have plausible explanations. Household evacuation preparation times are poorly predicted by demographic variables, but are better predicted by variables that predict evacuation decisions-perceived storm characteristics, expected personal impacts, and evacuation facilitators.

Keywords

Travel Demand Model; Decision-making; Communication; Prediction; Simulation; Hurricane Evacuation Models; Preparation Time Distributions; Mobilization Time Distributions; Departure Delay Time Distributions; Social Milling

Demystifying Progressive Design Build: Implementation Issues and Lessons Learned through Case Study Analysis

Shang, Luming; Migliaccio, Giovanni C. (2020). Demystifying Progressive Design Build: Implementation Issues and Lessons Learned through Case Study Analysis. Organization Technology And Management In Construction, 12(1), 2095 – 2108.

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Abstract

The design-build (DB) project delivery method has been used for several decades in the US construction market. DB contracts are usually awarded on the basis of a multicriteria evaluation, with price as one of the most salient criteria. To ensure the project's success, an owner usually has to invest enough time and effort during scoping and early design to define a program, scope, and budget, ready for procurement and price generation. However, this process can become a burden for the owner and may lengthen the project development duration. As an alternative to the traditional DB, the progressive design-build (PDB) approach permits the selection of the DB team prior to defining the project program and/or budget. PDB has the advantage of maintaining a single point of accountability and allowing team selection based mainly on qualifications, with a limited consideration of price. Under PDB, the selected team works with the project stakeholders during the early design stage, while helping the owner balance scope and budget. However, the key to the effectiveness of PDB is its provision for the ongoing and complete involvement of the owner in the early design phase. Due to the differences between PDB and the other project delivery methods (e.g., traditional DB), project teams must carefully consider several factors to ensure its successful implementation. The research team conducted a case study of the University of Washington's pilot PDB project to complete the West Campus Utility Plant (WCUP). This paper carefully explores and summarizes the project's entire delivery process (e.g., planning, solicitation, design, and construction), its organizational structures, and the project performance outcomes. The lessons learned from the WCUP project will contribute to best practices for future PDB implementation.

Keywords

Progressive Design Build; Project Delivery Method

Housing Wealth and Consumption over the 2001-2013 Period: The Role of the Collateral Channel

Acolin, Arthur. (2020). Housing Wealth and Consumption over the 2001-2013 Period: The Role of the Collateral Channel. Journal Of Housing Research, 29(1), 68 – 88.

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Abstract

This study estimates changes in the relationship between housing wealth and consumption among homeowners during the recent housing boom and bust in the United States, focusing on the period 2001-2007, during which house prices increased and financial innovations led to an increased availability of products enabling households to extract home equity; and on the period 2007-2013, during which house prices declined and home equity withdrawal products became largely unavailable. The estimated elasticity of consumption with regard to housing wealth increased in 2004 and 2007 (.06) relative to 2001 (.04). The estimated elasticities then decreased in 2010 and 2013 (to below .04). In addition, the increase was larger among borrowing constrained households than unconstrained households. No relationship between housing prices and consumption was found among renters. These additional tests for subpopulations support the hypothesis that the increase in consumption out of housing wealth occurred through the collateral channel.

Keywords

Consumption (economics); Wealth; Product Elimination; Equity (real Property); Home Prices; Home Ownership; United States; Collateral Channel; Credit And Consumption; Housing Wealth Effects; Housing; Housing Costs; Estimates; Prices; Households; Consumption; Equity; Borrowing; Hypotheses; Innovations; Elasticity Of Demand; Propensity To Consume; Housing Prices; Lines Of Credit; Mortgages; Subpopulations; Collateral; United States--us

Racial Disparity in Exposure to Housing Cost Burden in the United States: 1980-2017

Hess, Chris; Colburn, Gregg; Crowder, Kyle; Allen, Ryan. (2020). Racial Disparity in Exposure to Housing Cost Burden in the United States: 1980-2017. Housing Studies.

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Abstract

This article uses the Panel Study of Income Dynamics to analyse Black-White differences in housing cost burden exposure among renter households in the USA from 1980 to 2017, expanding understanding of this phenomenon in two respects. Specifically, we document how much this racial disparity changed among renters over almost four decades and identify how much factors associated with income or housing costs explain Black-White inequality in exposure to housing cost burden. For White households, the net contribution of household, neighbourhood and metropolitan covariates accounts for much of the change in the probability of housing cost burden over time. For Black households, however, the probability of experiencing housing cost burden continued to rise throughout the period of this study, even after controlling for household, neighbourhood and metropolitan covariates. This suggests that unobserved variables like racial discrimination, social networks or employment quality might explain the increasing disparity in cost burden among for Black and White households in the USA.

Keywords

Cost Burden; Housing Cost; Racial Inequality; Income Inequality; Rent Burden; Affordability; Neighborhoods; Segregation; Dynamics; Hardship; Prices; Market; Poor

Deep Neural Network Approach for Annual Luminance Simulations

Liu, Yue; Colburn, Alex; Inanici, Mehlika. (2020). Deep Neural Network Approach for Annual Luminance Simulations. Journal Of Building Performance Simulation, 13(5), 532 – 554.

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Abstract

Annual luminance maps provide meaningful evaluations for occupants' visual comfort and perception. This paper presents a novel data-driven approach for predicting annual luminance maps from a limited number of point-in-time high-dynamic-range imagery by utilizing a deep neural network. A sensitivity analysis is performed to develop guidelines for determining the minimum and optimum data collection periods for generating accurate maps. The proposed model can faithfully predict high-quality annual panoramic luminance maps from one of the three options within 30 min training time: (i) point-in-time luminance imagery spanning 5% of the year, when evenly distributed during daylight hours, (ii) one-month hourly imagery generated during daylight hours around the equinoxes; or (iii) 9 days of hourly data collected around the spring equinox, summer and winter solstices (2.5% of the year) all suffice to predict the luminance maps for the rest of the year. The DNN predicted high-quality panoramas are validated against Radiance renderings.

Keywords

Scattering Distribution-functions; Daylight Performance; Glare; Model; Prediction; Daylighting Simulation; Luminance Maps; Machine Learning; Neural Networks; Hdr Imagery; Panoramic View