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Department: College of Built Environments

Identification and Reduction of Synchronous Replacements in Life-Cycle Cost Analysis of Equipment

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)

A Time-Based Objective Measure of Exposure to the Food Environment

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

Opinion: Change Agency, Value Change

Cheng, Renée. (2020). Opinion: Change Agency, Value Change. Architect, 109(9), 20 – 20.

Keywords

Attitude Change (psychology); Air Flow; Hand Washing

Dynamic Production Scheduling Model Under Due Date Uncertainty in Precast Concrete Construction

Kim, Taehoon; Kim, Yong-Woo; Cho, Hunhee. (2020). Dynamic Production Scheduling Model Under Due Date Uncertainty in Precast Concrete Construction. Journal Of Cleaner Production, 257.

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Abstract

Precast concrete structures (PCs) are widely used in the construction industry to reduce project delivery times and improve quality. On-time delivery of PCs is critical for successful project completion because the processes involving precast concrete are the critical paths in most cases. However, existing models for scheduling PC production are not adequate for use in dynamic environments where construction projects have uncertain construction schedules because of various reasons such as poor labor productivity, inadequate equipment, and poor weather. This research proposes a dynamic model for PC production scheduling by adopting a discrete-time simulation method to respond to due date changes in real time and by using a new dispatching rule that considers the uncertainty of the due dates to minimize tardiness. The model is validated by simulation experiments based on various scenarios with different levels of tightness and due date uncertainty. The results of this research will contribute to construction project productivity with a reliable and economic precast concrete supply chain. (C) 2020 Elsevier Ltd. All rights reserved.

Keywords

Multiple Production; Demand Variability; Supply Chain; Shop; Management; Minimize; Lines; Precast Concrete Production; Dynamic Simulation; Uncertainty; Production Scheduling; Dispatching Rule

Climate-Driven Habitat Change Causes Evolution in Threespine Stickleback

Roches, Simone Des; Bell, Michael A.; Palkovacs, Eric P. (2020). Climate-Driven Habitat Change Causes Evolution in Threespine Stickleback. Global Change Biology, 26(2), 597 – 606.

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Abstract

Climate change can shape evolution directly by altering abiotic conditions or indirectly by modifying habitats, yet few studies have investigated the effects of climate-driven habitat change on contemporary evolution. We resampled populations of Threespine Stickleback (Gasterosteus aculeatus) along a latitudinal gradient in California bar-built estuaries to examine their evolution in response to changing climate and habitat. We took advantage of the strong association between stickleback lateral plate phenotypes and Ectodysplasin A (Eda) genotypes to infer changes in allele frequencies over time. Our results show that over time the frequency of low-plated alleles has generally increased and heterozygosity has decreased. Latitudinal patterns in stickleback plate phenotypes suggest that evolution at Eda is a response to climate-driven habitat transformation rather than a direct consequence of climate. As climate change has reduced precipitation and increased temperature and drought, bar-built estuaries have transitioned from lotic (flowing-water) to lentic (still-water) habitats, where the low-plated allele is favoured. The low-plated allele has achieved fixation at the driest, hottest southernmost sites, a trend that is progressing northward with climate change. Climate-driven habitat change is therefore causing a reduction in genetic variation that may hinder future adaptation for populations facing multiple threats.

Keywords

Gasterosteus-aculeatus; Natural-selection; 3-spined Stickleback; Armor; Populations; Patterns; Reductions; Adaptation; Capacity; Package; Climate Change; Gasterosteus Aculeatus; Intraspecific Variation; Latitudinal Gradient; Rapid Evolution; Resurvey; Space-for-time

Use of Health Impact Assessments in the Housing Sector to Promote Health in the United States, 2002-2016

Bever, Emily; Arnold, Kimberly T.; Lindberg, Ruth; Dannenberg, Andrew L.; Morley, Rebecca; Breysse, Jill; Pollack Porter, Keshia M. (2021). Use of Health Impact Assessments in the Housing Sector to Promote Health in the United States, 2002-2016. Journal Of Housing And The Built Environment, 36(3), 1277 – 1297.

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Abstract

Housing affects health, yet health is seldom considered in housing decisions. Health impact assessment (HIA) is a tool that can improve housing-related policies, plans, programs, and projects by bringing together scientific data, health expertise, and stakeholder engagement to identify the potential health effects of proposed decisions. We systematically identified and reviewed HIAs of housing decisions in the United States, yielding 54 HIAs between 2002 and 2016. Two examined federal proposals; the others explored decisions in 20 states. A variety of organizations led the HIAs, including non-profits, public health departments, and academic institutions. The primary decision-makers each HIA sought to inform were housing, planning, and/or elected officials. Eighteen HIAs focused on housing policies, codes, design elements, and utilities in residential structures. The remaining 36 HIAs included housing as one element of broader community development and transportation planning decisions. HIA recommendations changed decisions in some cases, and the assessment process helped strengthen connections between public health and housing decision-makers. To illustrate key characteristics of housing HIAs, we purposefully selected three HIAs and described the decisions they informed in detail: off-campus student housing in Flagstaff, Arizona; a rental housing inspections program in Portland, Oregon; and revitalization plans for a major thoroughfare in a suburb of St. Louis, Missouri. With a few exceptions, federal, state, and local agencies in the U.S. are not required to consider the health impacts of housing decisions, such as where housing is sited, how it is designed and constructed, and policies for ensuring that it is affordable and safe. HIA has emerged as a tool for advocates, health and housing practitioners, and policymakers to fill this gap. However, few studies have examined whether HIAs do in fact change housing decisions, shift the way that decision-makers think, or ultimately shift determinants of health (e.g., housing affordability and quality). This review demonstrates that HIAs can facilitate the consideration of health during housing decision-making. Housing HIAs can also help decision-makers address commonly overlooked effects, such as changes to social cohesion, and improve civic participation by engaging communities in the decisionmaking process.

Keywords

0; Community Development; Decision-making; Healthy Housing; Health Impact Assessment; Housing Policy; Stakeholder Engagement; Health Promotion; Public Health; Exceptions; Impact Analysis; Nonprofit Organizations; Affordability; Suburban Areas; Profits; Housing; Policy Making; Transportation Planning; Decision Making; Rental Housing; Public Officials; Policies; Regeneration; Utilities; Social Cohesion; Inspections; Community Involvement; Decision Makers; Community Participation; United States--us

Three Pathways to Highly Energy Efficient Buildings: Assessing Combinations of Teaming and Technology

Homayouni, Hoda; Dossick, Carrie Sturts; Neff, Gina. (2021). Three Pathways to Highly Energy Efficient Buildings: Assessing Combinations of Teaming and Technology. Journal Of Management In Engineering, 37(2).

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Abstract

Highly energy efficient (HEE) buildings require a whole-system approach to building design. Scholars have suggested many tools, techniques, and processes to address the cross-disciplinary complexities of such an approach, but how these elements might be best combined to lead to better project outcomes is yet unknown. To address this, we surveyed architects associated with 33 AIA-COTE award-winning projects on the social, organizational, and technological elements of whole-system design (WSD) practices. We then used fuzzy sets-qualitative comparative analysis (fsQCA) to analyze the interdependencies among those elements. We found three distinct pathways for the design and construction of HEE buildings: information-driven, process-driven, or organization-driven. We also found that HEE buildings share some conditions for success, including having shared goals, owners engagement in the design process, and frequent and participatory interorganizational meetings. Our findings can help practitioners strategize and make decisions on incorporating WSD elements associated with their project types. Moreover, these results provide a launchpad for scholars to investigate complementarities among elements facilitating the design and construction process of HEE projects.

Keywords

Buildings (structures); Construction; Design Engineering; Energy Conservation; Fuzzy Set Theory; Innovation Management; Organisational Aspects; Project Management; Team Working; Whole-system Approach; Building Design; Cross-disciplinary Complexities; Social Elements; Organizational Elements; Technological Elements; Whole-system Design Practices; Fuzzy Set; Distinct Pathways; Hee Buildings; Project Types; Construction Process; Hee Projects; Highly Energy Efficient Buildings; Whole-system Design; Energy Efficient Buildings; Building Information Modeling; Integrated Project Teams; Fuzzy Sets-qualitative Comparative Analysis

Triggering a Climate Change Dominated Anthropocene: Is it Common Among Exocivilizations

Savitch, Ethan; Frank, Adam; Carroll-Nellenback, Jonathan; Haqq-Misra, Jacob; Kleidon, Axel; Alberti, Marina. (2021). Triggering a Climate Change Dominated Anthropocene: Is it Common Among Exocivilizations? Astronomical Journal, 162(5).

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Abstract

We seek to model the coupled evolution of a civilization and its host planet through the era when energy harvesting by the civilization drives the planet into new and adverse climate states. In this way, we ask if triggering Anthropocenes of the kind humanity is experiencing might be a generic feature of planet-civilization evolution. This question has direct consequences for both the study of astrobiology and the sustainability of human civilization. Furthermore, if Anthropocenes prove fatal for some civilizations then they can be considered as one form of a Great Filter and are therefore relevant to discussions of the Fermi Paradox. In this study, we focus on the effects of energy harvesting via combustion and vary the planet's initial chemistry and orbital radius. We find that in this context, the most influential parameter dictating a civilization's fate is their host planet's climate sensitivity, which quantifies how global temperatures change as CO2 is added to the atmosphere. Furthermore, this is in itself a function of the planet's atmospheric CO2 level, so planets with low levels of CO2 will have high climate sensitivities and high probabilities of triggering climate change. Using simulations of the coupled nonlinear model combined with semi-analytic treatments, we find that most planets in our initial parameter space experience diminished growth due to climate effects, an event we call a climate-dominated Anthropocene.

Keywords

Habitable Planets; Complex Life; Evolution; Earth

Geographic Ecological Momentary Assessment Methods to Examine Spatio-temporal Exposures Associated with Marijuana Use Among Young Adults: A Pilot Study

Rhew, Isaac C.; Hurvitz, Philip M.; Lyles-riebli, Rose; Lee, Christine M. (2022). Geographic Ecological Momentary Assessment Methods to Examine Spatio-temporal Exposures Associated with Marijuana Use Among Young Adults: A Pilot Study. Spatial And Spatio-temporal Epidemiology, 41.

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Abstract

Background: This study demonstrates the use of geographic ecological momentary assessment (GEMA) methods among young adult marijuana users. Method: Participants were 14 current marijuana users ages 21-27 living in Greater Seattle, Washington. They completed brief surveys four times per day for 14 consecutive days, including measures of marijuana use and desire to use. They also carried a GPS data logger that tracked their spatial movements over time. Results: Participants completed 80.1% of possible EMA surveys. Using the GPS data, we calculated daily number of exposures to (i.e., within 100-m of) marijuana retail outlets (mean = 3.9 times per day; SD = 4.4) and time spent per day in high poverty census tracts (mean = 7.3 h per day in high poverty census tracts; SD = 5.1). Conclusions: GEMA may be a promising approach for studying the role spatio-temporal factors play in marijuana use and related factors.

Keywords

Geographic Ecological Momentary Assessment; Spatio-temporal Factors; Marijuana; Young Adults; Geographic Information System; Poverty; Substance Use; Alcohol; Tracking

Assessment of Data Quality for Evaluations of Manual Pavement Distress

Bogus, Susan M.; Migliaccio, Giovanni C.; Cordova, Arturo A. (2010). Assessment of Data Quality for Evaluations of Manual Pavement Distress. Transportation Research Record, 2170, 1 – 8.

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Abstract

Assessment of the conditions of current assets is a task of major relevance in a transportation agency asset management program It not only provides information on the current condition of the asset but also helps the agency make decisions on future maintenance and rehabilitation activities Although low volume roadways represent a large proportion of the total road network in the United States little research on the management of these assets has been done Two major data collection techniques are used for roadway condition assessment manual and automated Although automated techniques have been found to be safer and quicker manual condition surveys have been proven to offer preciseness and cost effectiveness In the case of low volume roadway assessment for which the funds available to asset managers are limited manual condition surveys are often preferred Nevertheless manual condition surveys must address the potential subjectivity of the results Therefore agencies could benefit from a system for ensuring quality on manual condition surveys This paper proposes a framework for assessment of data quality and presents a case study of its implementation in the Northern New Mexico Pavement Evaluation Program The proposed framework is easily implementable and able to identify potential and actual data collection issues The framework can be used as part of an asset management program and could be particularly beneficial in the case of low volume roads

Keywords

Interrater Reliability; Agreement; Ratings