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A Simulation-Based Dynamic Scheduling Model for Curtain Wall Production Considering Construction Planning Reliability

Kim, Taehoon; Kim, Yong-Woo; Cho, Hunhee. (2021). A Simulation-Based Dynamic Scheduling Model for Curtain Wall Production Considering Construction Planning Reliability. Journal Of Cleaner Production, 286.

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Abstract

Appropriate production scheduling of curtain wall systems is essential for the successful completion of construction projects. The construction process of the curtain wall system is mainly on the critical path and accounts for 10-15% of the total construction cost. Should curtain wall products not be timeously delivered to the construction site, construction projects are likely to fall behind schedule with most relevant activities on curtainwall installation on a critical path. However, due-date uncertainty caused by a contractor's lack of planning reliability causes the curtain wall production schedule to become complex and changes the due date after the initial order. In this regard, this study proposes a discrete event simulation-based dynamic scheduling model for curtain wall production to deliver products on time to the construction site by considering each construction project's planning reliability. Through simulation experiments, the validity and effectiveness of the proposed model were tested. The results of this study will help the successful completion of construction projects by ensuring the progress of the curtain wall system construction and follow-up activities following the construction schedule. (C) 2020 Elsevier Ltd. All rights reserved.

Keywords

Construction Industry; Discrete Event Simulation; Dynamic Scheduling; Production Control; Production Planning; Project Management; Reliability; Scheduling; Walls; Construction Planning Reliability; Construction Schedule; Curtain Wall System Construction; Construction Project; Discrete Event Simulation-based Dynamic Scheduling Model; Curtain Wall Production Schedule; Curtain Wall Installation; Curtain Wall Products; Total Construction Cost; Critical Path; Production Scheduling; Off-site Construction; Demand Variability; Job Shops; Precast; Minimize; Number; Curtain Wall; Simulation; Planning Reliability; Dispatching Rule

Exploring Partnership Between Transit Agency And Shared Mobility Company: An Incentive Program For App-based Carpooling

Shen, Qing; Wang, Yiyuan; Gifford, Casey. (2021). Exploring Partnership Between Transit Agency And Shared Mobility Company: An Incentive Program For App-based Carpooling. Transportation, 48(5), 2585 – 2603.

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Abstract

How should public transit agencies deliver mobility services in the era of shared mobility? Previous literature recommends that transit agencies actively build partnerships with mobility service companies from the private sector, yet public transit agencies are still in search of a solid empirical basis to help envision the consequences of doing so. This paper presents an effort to fill this gap by studying a recent experiment of shared mobility public-private partnership, the carpool incentive fund program launched by King County Metro in the Seattle region. This program offers monetary incentives for participants who commute using a dynamic app-based carpooling service. Through descriptive analysis and a series of logistic regression models, we find that the monetary incentive to encourage the use of app-based carpooling generates some promising outcomes while having distinctive limitations. In particular, it facilitates the growth of carpooling by making carpooling a competitive commuting option for long-distance commuters. Moreover, our evidence suggests that the newly generated carpooling trips mostly substitute single-occupancy vehicles, thus contributing to a reduction of regional VMT. The empirical results of this research will not only help King County Metro devise its future policies but also highlight an appealing alternative for other transit agencies in designing an integrated urban transportation system in the era of shared mobility.

Keywords

Shared Mobility; Public-Private Partnership; App-based Carpooling; Incentive Fund; Transit Agencies; Incentives; Commuting; Public Transportation; Mobility; Regression Analysis; Regression Models; Partnerships; Vehicles; Car Pools; Private Sector; Occupancy; Transportation Systems; Mass Transit; Transportation Planning; Empirical Analysis; Urban Transportation

Associations of Cannabis Retail Outlet Availability and Neighborhood Disadvantage with Cannabis Use and Related Risk Factors Among Young Adults in Washington State

Rhew, Isaac C.; Guttmannova, Katarina; Kilmer, Jason R.; Fleming, Charles B.; Hultgren, Brittney A.; Hurvitz, Philip M.; Dilley, Julia A.; Larimer, Mary E. (2022). Associations of Cannabis Retail Outlet Availability and Neighborhood Disadvantage with Cannabis Use and Related Risk Factors Among Young Adults in Washington State. Drug & Alcohol Dependence, 232.

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Abstract

Background: This study examined associations of local cannabis retail outlet availability and neighborhood disadvantage with cannabis use and related risk factors among young adults. Methods: Data were from annual cross-sectional surveys administered from 2015 to 2019 to individuals ages 18-25 residing in Washington State (N = 10,009). As outcomes, this study assessed self-reported cannabis use at different margins/frequencies (any past year, at least monthly, at least weekly, at least daily) and perceived ease of access to cannabis and acceptability of cannabis use in the community. Cannabis retail outlet availability was defined as the presence of at least one retail outlet within a 1-kilometer road network buffer of one's residence. Sensitivity analyses explored four other spatial metrics to define outlet availability (any outlet within 0.5-km, 2-km, and the census tract; and census tract density per 1000 residents). Census tract level disadvantage was a composite of five US census variables. Results: Adjusting for individual- and area-level covariates, living within 1-kilometer of at least one cannabis retail outlet was statistically significantly associated with any past year and at least monthly cannabis use as well as high perceived access to cannabis. Results using a 2-km buffer and census tract-level metrics for retail outlet availability showed similar findings. Neighborhood disadvantage was statistically significantly associated with at least weekly and at least daily cannabis use and with greater perceived acceptability of cannabis use. Conclusions: Results may have implications for regulatory and prevention strategies to reduce the population burden of cannabis use and related harms.

Keywords

Outlet Stores; Young Adults; Neighborhoods; Older People; Sensitivity Analysis; Washington (state); Cannabis; Cannabis Retail Outlets; Neighborhood Disadvantage; Alcohol-use; Marijuana Use; Density; Proximity; Health; Norms

Potential Impacts Of Washington State’s Wildfire Worker Protection Rule On Construction Workers.

Zuidema, Christopher; Austin, Elena; Cohen, Martin A.; Kasner, Edward; Liu, Lilian; Isaksen, Tania Busch; Lin, Ken-Yu; Spector, June; Seto, Edmund. (2022). Potential Impacts Of Washington State’s Wildfire Worker Protection Rule On Construction Workers. Annals Of Work Exposures & Health, 66(4), 419 – 432.

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Abstract

Driven by climate change, wildfires are increasing in frequency, duration, and intensity across the Western United States. Outdoor workers are being exposed to increasing wildfire-related particulate matter and smoke. Recognizing this emerging risk, Washington adopted an emergency rule and is presently engaged in creating a permanent rule to protect outdoor workers from wildfire smoke exposure. While there are growing bodies of literature on the exposure to and health effects of wildfire smoke in the general public and wildland firefighters, there is a gap in knowledge about wildfire smoke exposure among outdoor workers generally and construction workers specifically-a large category of outdoor workers in Washington totaling 200,000 people. Several data sources were linked in this study-including state-collected employment data and national ambient air quality data-to gain insight into the risk of PM2.5 exposure among construction workers and evaluate the impacts of different air quality thresholds that would have triggered a new Washington emergency wildfire smoke rule aimed at protecting workers from high PM2.5 exposure. Results indicate the number of poor air quality days has increased in August and September in recent years. Over the last decade, these months with the greatest potential for particulate matter exposure coincided with an annual peak in construction employment that was typically 9.4-42.7% larger across Washington counties (one county was 75.8%). Lastly, the 'encouraged' threshold of the Washington emergency rule (20.5 mu g m(-3)) would have resulted in 5.5 times more days subject to the wildfire rule on average across all Washington counties compared to its 'required' threshold (55.5 mu g m(-3)), and in 2020, the rule could have created demand for 1.35 million N-95 filtering facepiece respirators among construction workers. These results have important implications for both employers and policy makers as rules are developed. The potential policy implications of wildfire smoke exposure, exposure control strategies, and data gaps that would improve understanding of construction worker exposure to wildfire smoke are also discussed.

Keywords

Particulate Matter; Industrial Safety; Occupational Exposure; Rules; Smoke; Construction Industry; Employment; Occupational Hazards; Descriptive Statistics; Industrial Hygiene; Wildfires; N95 Respirators; Washington (state); Forest Fires; Pm 2.5; Respirator; Wildfire Smoke Protection Rule; Wildland Fire; Pm2 5; Health Impacts; Climate-change; Forest-fire; Exposure; Firefighters; Infiltration

Performance Assessment of a Street-Drainage Bioretention System

Chapman, Cameron; Horner, Richard R. (2010). Performance Assessment of a Street-Drainage Bioretention System. Water Environment Research, 82(2), 109 – 119.

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Abstract

Event-based, flow-paced composite sampling was carried out at the inlet and outlet of a street-side bioretention facility in Seattle, Washington, to assess its ability to reduce street runoff quantity and pollutants. Over 2.5 years, 48 to 74% of the incoming runoff was lost to infiltration and evaporation. Outlet pollutant concentrations were significantly lower than those at the inlet for nearly all monitored constituents. In terms of mass, the system retained most of the incoming pollutants. Besides soluble reactive phosphorus (the mass of which possibly increased), dissolved copper was the least effectively retained; at least 58% of dissolved copper (and potentially as much as 79%) was captured by the system. Motor oil was removed most effectively, with 92 to 96% of the incoming motor oil not leaving the system. The results indicate that bioretention systems can achieve a high level of runoff retention and treatment in real-weather conditions. Water Environ. Res., 82, 109 (2010).

Keywords

Stormwater; Removal; Runoff; Bioretention; Water Quality Monitoring; Best Management Practices; Low-impact Development

Building Bosnia

Winterbottom, Daniel. (2010). Building Bosnia. Landscape Architecture, 100(4), 94 – 102.

Are We Prepared for the Economic Risk Resulting from Telecom Hotel Disruptions?

Armbruster, Ginger; Endicott-Popousky, Barbara; Whittington, Jan. (2012). Are We Prepared for the Economic Risk Resulting from Telecom Hotel Disruptions? International Journal Of Critical Infrastructure Protection, 5(2), 55 – 65.

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Abstract

Large and small businesses in Seattle, Washington, as in most urban centers across the United States, increasingly rely on telecom hotels and related telecommunications centers to conduct business operations. What would be the economic impact to these businesses if a natural or man-made disaster were to make this infrastructure unavailable for a significant period of time? How long would it take for the owners of small businesses, which provide the foundation for economic recovery, to give up and move away? Are metropolitan regions prepared for this risk? This paper draws on publicly available reports of telecom hotel investments to examine the economic risks that such telecommunications hubs pose at the regional scale. New York City and Seattle are two urban areas that depend on key investments in telecom hotels. In the Pacific Northwest, these assets are located downtown, primarily in the center of the urban real estate market of Seattle. Although the terrorist attacks of September 11, 2001 were directed at the World Trade Center in Lower Manhattan, collateral damage to a major telecommunications hub brought outages during and after the attacks that highlighted the serious risk posed to small- and mid-sized businesses from disruptions in telecommunications service. The Seattle case study illustrates the potential to learn from the experience in Lower Manhattan and apply this knowledge across the United States. Regional economic analysis of the benefits of and the means to protect small- and mid-sized businesses can provide the basis for strategic investments that minimize economic loss and reduce the recovery time. (C) 2012 Elsevier B.V. All rights reserved.

Keywords

Telecommunications Hubs; Telecom Hotels; Business Continuity; Risk

The San Francisco Peninsula’s Great Estates: Part I

Streatfield, David C. (2012). The San Francisco Peninsula’s Great Estates: Part I. Eden, 15(1), 1 – 14.

Abstract

The article presents a historical background of several great estates in San Francisco Peninsula in California known for their unique landscaping and special garden designs in the late 19th and early 20th centuries. It discusses the climate and settlement styles in the area and offers information on the earliest estates such as the El Cerrito created by merchant William Davis Merry Howard and the notable mid-Victorian estates such as the Millbrae estate of banker Darius Ogden Mills.

Keywords

Garden Design; Landscape Design; Landscape Gardening; San Francisco Peninsula (calif.); California

Walking Objectively Measured: Classifying Accelerometer Data with GPS and Travel Diaries

Kang, Bumjoon; Moudon, Anne V.; Hurvitz, Philip M.; Reichley, Lucas; Saelens, Brian E. (2013). Walking Objectively Measured: Classifying Accelerometer Data with GPS and Travel Diaries. Medicine & Science In Sports & Exercise, 45(7), 1419 – 1428.

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Abstract

Purpose: This study developed and tested an algorithm to classify accelerometer data as walking or nonwalking using either GPS or travel diary data within a large sample of adults under free-living conditions. Methods: Participants wore an accelerometer and a GPS unit and concurrently completed a travel diary for seven consecutive days. Physical activity (PA) bouts were identified using accelerometry count sequences. PA bouts were then classified as walking or nonwalking based on a decision-tree algorithm consisting of seven classification scenarios. Algorithm reliability was examined relative to two independent analysts' classification of a 100-bout verification sample. The algorithm was then applied to the entire set of PA bouts. Results: The 706 participants' (mean age = 51 yr, 62% female, 80% non-Hispanic white, 70% college graduate or higher) yielded 4702 person-days of data and had a total of 13,971 PA bouts. The algorithm showed a mean agreement of 95% with the independent analysts. It classified PA into 8170 walking bouts (58.5 %) and 5337 nonwalking bouts (38.2%); 464 bouts (3.3%) were not classified for lack of GPS and diary data. Nearly 70% of the walking bouts and 68% of the nonwalking bouts were classified using only the objective accelerometer and GPS data. Travel diary data helped classify 30% of all bouts with no GPS data. The mean + SD duration of PA bouts classified as walking was 15.2 + 12.9 min. On average, participants had 1.7 walking bouts and 25.4 total walking minutes per day. Conclusions: GPS and travel diary information can be helpful in classifying most accelerometer-derived PA bouts into walking or nonwalking behavior.

Keywords

Walking; Algorithms; Decision Trees; Geographic Information Systems; Research Funding; Travel; Accelerometry; Diary (literary Form); Descriptive Statistics; Algorithm; Classification; Physical Activity; Walk Trip; Global Positioning Systems; Physical-activity; Environment; Behaviors; Validity; Location

Comparative Analysis of Hospital Energy Use: Pacific Northwest and Scandinavia

Burpee, Heather; McDade, Erin. (2014). Comparative Analysis of Hospital Energy Use: Pacific Northwest and Scandinavia. Health Environments Research & Design Journal (HERD) (Vendome Group LLC), 8(1), 20 – 44.

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Abstract

OBJECTIVE: This study aimed to establish the potential for significant energy reduction in hospitals in the United States by providing evidence of Scandinavian operational precedents with high Interior Environmental Quality (IEQ) and substantially lower energy profiles than comparable U.S. facilities. These facilities set important precedents for design teams seeking operational examples for achieving aggressive energy and interior environmental quality goals. This examination of operational hospitals is intended to offer hospital owners, designers, and building managers a strong case and concrete framework for strategies to achieve exceptionally high performing buildings. BACKGROUND: Energy efficient hospitals have the potential to significantly impact the U.S.'s overall energy profile, and key stakeholders in the hospital industry need specific, operationally grounded precedents in order to successfully implement informed energy reduction strategies. This study is an outgrowth of previous research evaluating high quality, low energy hospitals that serve as examples for new high performance hospital design, construction, and operation. Through extensive interviews, numerous site visits, the development of case studies, and data collection, this team has established thorough qualitative and quantitative analyses of several contemporary hospitals in Scandinavia and the Pacific Northwest. Many Scandinavian hospitals demonstrate a low energy profile, and when analyzed in comparison with U.S. hospitals, such Scandinavian precedents help define the framework required to make significant changes in the U.S. hospital building industry. METHODS: Eight hospitals, four Scandinavian and four Pacific Northwest, were quantitatively compared using the Environmental Protection Agency's Portfolio Manager, allowing researchers to answer specific questions about the impact of energy source and architectural and mechanical strategies on energy efficiency in operational hospitals. RESULTS: Specific architectural, mechanical, and plant systems make these Scandinavian hospitals more energy efficient than their Pacific Northwest counterparts. More importantly, synergistic systems integration allows for their significant reductions in energy consumption. CONCLUSIONS: This quantitative comparison of operational Scandinavian and Pacific Northwest hospitals resulted in compelling evidence of the potential for deep energy savings in the U.S., and allowed researchers to outline specific strategies for achieving such reductions.

Keywords

Environmental Quality; Energy Consumption; Health Facility Design & Construction; Comparative Studies; Energy Consumption In Hospitals; Pacific Northwest; Scandinavia; Built Environment; Case Study; Design Process; Healthcare Facility Design; Hospital; Post Occupancy