Oshima, K. T. (Ed.). (2016). Kiyonori Kikutake: Between Land and Sea. Lars Müller Publishers.
Year: 2016
Borrowing Constraints and Homeownership
Acolin, Arthur; Bricker, Jesse; Calem, Paul; Wachter, Susan. (2016). Borrowing Constraints and Homeownership. The American Economic Review, 106(5), 625 – 629.
Keywords
Borrowing Constraints, Homeownership, Credit Supply
A Renter or Homeowner Nation?
Acolin, Arthur; Goodman, Laurie S.; Wachter, Susan M. (2016). A Renter or Homeowner Nation? Cityscape, 18(1), 145 – 158.
Deconstructing the Construction Industry: A Spatiotemporal Clustering Approach to Profitability Modeling
Choi, Kunhee; Lee, Hyun Woo. (2016). Deconstructing the Construction Industry: A Spatiotemporal Clustering Approach to Profitability Modeling. Journal Of Construction Engineering And Management, 142(10).
Abstract
In spite of the strong influence of the construction industry on the national health of the United States' economy, very little research has specifically aimed at evaluating the key performance parameters and trends (KPPT) of the industry. Due to this knowledge gap, concerns have been constantly raised over lack of accurate measures of KPPT. To circumvent these challenges, this study investigates and models the macroeconomic KPPT of the industry through spatiotemporal clustering modeling. This study specifically aims to analyze the industry in 14 of its subsectors and subsequently, by 51 geographic spatial areas at a 15-year temporal scale. KPPT and their interdependence were firstly examined by utilizing the interpolated comprehensive U.S. economic census data. A hierarchical spatiotemporal clustering analysis was then performed to create predictive models that can reliably determine firm's profitability as a function of the key parameters. Lastly, the robustness of the predictive models was tested by a cross-validation technique called the predicted error sum of square. This study yields a notable conclusion that three key performance parameterslabor productivity, gross margin, and labor wageshave steadily improved over the study period from 1992 to 2007. This study also reveals that labor productivity is the most critical factor; the states and subsectors with the highest productivity are the most profitable. This study should be of value to decision-makers when plotting a roadmap for future growth and rendering a strategic business decisions.
Keywords
Construction Industry; Decision Making; Knowledge Management; Labour Resources; Macroeconomics; Organisational Aspects; Productivity; Profitability; Salaries; Statistical Analysis; Strategic Planning; Hierarchical Spatiotemporal Clustering Approach; National Health; Macroeconomic Kppt; Knowledge Gap; Spatiotemporal Clustering Modeling; Interpolated Comprehensive U.s. Economic Census Data; Parameters-labor Productivity; Gross Margin; Labor Wages; Strategic Business Decisions; Deconstructing; Key Performance Parameters And Trends; Firms Profitability; Error Sum Of Square; Labor Productivity; Projects; Firms; Performance; Performance Measurement; Cluster Analysis; Economic Census; Project Planning And Design
Cross Sectional Association between Spatially Measured Walking Bouts and Neighborhood Walkability
Hwang, Liang-dar; Hurvitz, Philip M.; Duncan, Glen E. (2016). Cross Sectional Association between Spatially Measured Walking Bouts and Neighborhood Walkability. International Journal Of Environmental Research And Public Health, 13(4).
Abstract
Walking is the most popular choice of aerobic physical activity to improve health among U.S. adults. Physical characteristics of the home neighborhood can facilitate or hinder walking. The purpose of this study was to quantify neighborhood walking, using objective methods and to examine the association between counts of walking bouts in the home neighborhood and neighborhood walkability. This was a cross-sectional study of 106 adults who wore accelerometers and GPS devices for two weeks. Walking was quantified within 1, 2, and 3 km Euclidean (straight-line) and network buffers around the geocoded home location. Walkability was estimated using a commercially available index. Walking bout counts increased with buffer size and were associated with walkability, regardless of buffer type or size (p < 0.001). Quantification of walking bouts within (and outside) of pre-defined neighborhood buffers of different sizes and types allowed for the specification of walking locations to better describe and elucidate walking behaviors. These data support the concept that neighborhood characteristics can influence walking among adults.
Keywords
Physical-activity; Accelerometer Data; United-states; Urban Form; Land-use; Validation; Health; Transportation; Environments; Intensity; Geographic Information Systems; Residence Characteristics; Twins; Walking
Study on the Ownership of Motorized and Non-Motorized Vehicles in Suburban Metro Station Areas: A Structural Equation Approach
Pan, Haixiao; Li, Jing; Chen, Peng. (2016). Study on the Ownership of Motorized and Non-Motorized Vehicles in Suburban Metro Station Areas: A Structural Equation Approach. Urban Rail Transit, 2(2), 47 – 58.
Abstract
As Chinese megacities are experiencing a large-scale motorization and suburbanization, an ever greater number of households are relocated to suburban towns. The increasing average travel distance surely encourages car growth. China is now the world's largest car consumer, resulting in a series of unforeseen environmental and public health issues. On the other hand, scooters, electric bikes, and motorcycles become attractive options to substitute non-motorized bicycles. The ongoing demographic changes should also be taken in account. China has a rapidly aging population and a higher birth rate following reforms to the one-child policy allowing couples to have a second child. These changes will lead to a dramatic alteration of the household composition in the near future. Under above emerging contexts, this study aims to understand what implies the ownership of motorized and non-motorized vehicles in suburban metro station areas by means of a structural equation model. The data employed in this study are based on a household survey collected from three neighborhoods in Shanghai suburban metro station areas in 2010. The major findings include: (1) Income is a decisive element in car ownership. Specifically, high-income households have higher propensity to own a car, while middle and poor income families tend to own scooters, electric bikes, motorcycles, or bicycles. (2) Workplace built environment features or mode preferences are not essential to understanding vehicle ownership in Chinese context. (3) Stem families are more likely to own cars; the presence of a child or a senior family member increases the probability of owning a car by enlarging the household. (4) The results estimated for core family and DINK (couple with no child) family are highly consistent, and these families are less likely to own cars. Therefore, transport policies may focus more on households. Providing safe, pleasant, and efficient pedestrian and bicycle paths for children and seniors may decrease the attractiveness of owning cars.
Keywords
Suburban Metro Station Areas; Ownership Of Motorized And Non-motorized Vehicles; Built Environment; Mode Preferences; Family Composition; Structural Equation Model
Time-Cost Performance Effect of Change Orders from Accelerated Contract Provisions
Choi, Kunhee; Lee, Hyun Woo; Bae, Junseo; Bilbo, David. (2016). Time-Cost Performance Effect of Change Orders from Accelerated Contract Provisions. Journal Of Construction Engineering And Management, 142(3).
Abstract
Accelerated contract provisions (ACPs) such as cost-plus-time (A+B) and incentives/disincentives (I/D) are increasingly common, yet very little is known about their pure time-cost performance effects on change orders. To fill this large knowledge gap, a two-stage research methodology drawing on 1,372 highway improvement projects completed in California was adopted for this study. The Stage I study investigated the marginal change-order impacts of two ACPs, pure A+B and I/D combined with A+B. How ACP change orders affect projects' time-cost performance was numerically modeled and successfully validated over the Stage II study. The results clearly showed that both ACPs led to more schedule-change and cost-change orders than conventionally contracted projects, whereas I/D combined with A+B performed significantly better than pure A+B in terms of the magnitude of schedule-change orders. This conveys an important recommendation to state transportation agencies (STAs) that A+B be used with an I/D provision. The results and numerical models of this study would help STAs better assess and justify the impact of change orders on the duration and cost of projects, enabling them to more effectively use contingency amounts. Use of the models can also benefit contractors requesting a change order because the models can provide them with advanced knowledge of the probable time-cost growth rates specifically for the pursued ACP. (C) 2015 American Society of Civil Engineers.
Keywords
Construction Industry; Contracts; Costing; Incentive Schemes; Numerical Analysis; Order Processing; Performance Evaluation; Roads; Scheduling; Time Management; Transportation; Projects Time-cost Performance Effect; Cost-change Order; Accelerated Contract Provision; Knowledge Gap; California; Acp; Schedule-change Order; State Transportation Agency; Numerical Model; Sta; Incentive; Highway Improvement Project; Labor Productivity; Construction; Impact; Model; Projects; Change Order; Highway Rehabilitation; Decision Modeling; Regression; Validation; Contracting
Spatial Energetics Integrating Data from GPS, Accelerometry, and GIS to Address Obesity and Inactivity
James, Peter; Jankowska, Marta; Marx, Christine; Hart, Jaime E.; Berrigan, David; Kerr, Jacqueline; Hurvitz, Philip M.; Hipp, J. Aaron; Laden, Francine. (2016). Spatial Energetics Integrating Data from GPS, Accelerometry, and GIS to Address Obesity and Inactivity. American Journal Of Preventive Medicine, 51(5), 792 – 800.
Abstract
To address the current obesity and inactivity epidemics, public health researchers have attempted to identify spatial factors that influence physical inactivity and obesity. Technologic and methodologic developments have led to a revolutionary ability to examine dynamic, high-resolution measures of temporally matched location and behavior data through GPS, accelerometry, and GIS. These advances allow the investigation of spatial energetics, high-spatiotemporal resolution data on location and time-matched energetics, to examine how environmental characteristics, space, and time are linked to activity-related health behaviors with far more robust and detailed data than in previous work. Although the transdisciplinary field of spatial energetics demonstrates promise to provide novel insights on how individuals and populations interact with their environment, there remain significant conceptual, technical, analytical, and ethical challenges stemming from the complex data streams that spatial energetics research generates. First, it is essential to better understand what spatial energetics data represent, the relevant spatial context of analysis for these data, and if spatial energetics can establish causality for development of spatially relevant interventions. Second, there are significant technical problems for analysis of voluminous and complex data that may require development of spatially aware scalable computational infrastructures. Third, the field must come to agreement on appropriate statistical methodologies to account for multiple observations per person. Finally, these challenges must be considered within the context of maintaining participant privacy and security. This article describes gaps in current practice and understanding and suggests solutions to move this promising area of research forward. (C) 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
Keywords
Physical-activity Levels; Built Environment; Activity Monitors; Travel Behavior; Health Research; Neighborhood; Exposure; Validation; Children; Design
Physical Activity and the Built Environment in Residential Neighborhoods of Seoul and Seattle: An Empirical Study Based on Housewives’ GPS Walking Data and Travel Diaries
Park, Sohyun; Choi, Yeemyung; Seo, Hanlim; Moudon, Anne Vernez; Bae, C. -h. Christine; Baek, So-ra. (2016). Physical Activity and the Built Environment in Residential Neighborhoods of Seoul and Seattle: An Empirical Study Based on Housewives’ GPS Walking Data and Travel Diaries. Journal Of Asian Architecture And Building Engineering, 15(3), 471 – 478.
Abstract
This paper is based on a collaborative pilot-study to ascertain the characteristic walking patterns and neighborhood features in residential areas of Seoul, Korea and Seattle, USA. As for sample sites, four case neighborhoods were selected: two from Seoul and two from in and outside of the Seattle-Shoreline areas. As for participants, thirty Korean housewives in Seoul and thirty Korean-American housewives in the Seattle area were selected respectively, and their socio-demographic characteristics, GPS records, and travel diary data for seven days were collected and analyzed. Considering the typical rainy seasons in the two cities, data collections, including the physical activity assessment by GPS devices, were carried out from May to June and from September to October in Seoul, and from July to October in Seattle during the year 2010. Noteworthy research findings include the following: Korean participants in Seoul walk about 2.6 km on average per day, while Korean-American participants in Seattle walk about 400m on average per day. In the case sites of Seoul, 75% of grocery shopping activities happen within the neighborhood by walking, while only 17% of those activities on foot happen in the case sites of Seattle. As for the most walking activity, about 70% of total walking amounts are related to utilitarian walking in Seoul sites, while 50% of total walking are related to recreational walking in Seattle sites. Recreational walking and utilitarian walking occur separately in Seattle sites, while the two walking types are often combined in Seoul sites, which also contribute to more walking amounts and farther walking distances in Seoul sites. This paper empirically confirms the widely held assumptions in part that residents in Seoul, a relatively high-density and high mixed-use city, walk more than those in Seattle, a relatively low-density and low mixed-use city. This paper also recognizes that in the case of both cities, more walking activities occur in the neighborhood built environment, where finely-grained street networks, small lots and blocks, various pedestrian destinations, public transit access, etc are provided in close connection. The amount and frequency of walking activities, as well as the fineness of neighborhood features, however, are remarkably different in the two cities, whose implications deserve in-depth exploration in further studies.
Keywords
Urban Design; Physical Activity; Neighborhood Environment; Objective Measures; Gps Walking Data; International Comparative Study
Environmental, Economic, and Social Implications of Highway Concrete Rehabilitation Alternatives
Choi, Kunhee; Lee, Hyun Woo; Mao, Zhuting; Lavy, Sarel; Ryoo, Boong Yeol. (2016). Environmental, Economic, and Social Implications of Highway Concrete Rehabilitation Alternatives. Journal Of Construction Engineering And Management, 142(2).
Abstract
Currently, there is no comprehensive benchmark of life-cycle assessment for the rigid pavement alternatives for highway rehabilitation. To fill this gap, the major objective of this study is to investigate the environmental, economic, and social impacts of the three most widely adopted rigid pavement choices through a life-cycle assessment approach with custom-built economic input-output life-cycle assessment (EIO-LCA) models. Quantity takeoffs were performed for each alternative assuming a 1-lane-km highway rehabilitation. Subsequently, the construction costs of each alternative were computed in order to determine the present values for a life span of 50years, while at the same time accounting for a different life expectancy for each pavement rehabilitation strategy. The present values were then incorporated into a corresponding EIO-LCA model. The results clearly indicate that continuously reinforced concrete pavement (CRCP) is the most sustainable choice and much preferable to the other alternatives for minimizing negative environmental, economic and social impacts from the life-cycle perspective. This finding champions a wider adoption of CRCP for future sustainable transportation infrastructure development projects, as CRCP's relatively high initial construction cost can be recouped by long-term sustained benefits. The results and findings of this study can serve as a solid foundation for industry practitioners and decision-makers to make better-informed project decisions when choosing the most sustainable pavement alternatives from a life-cycle perspective. (C) 2015 American Society of Civil Engineers.
Keywords
Construction Industry; Environmental Management; Life Cycle Costing; Product Life Cycle Management; Project Management; Reinforced Concrete; Road Building; Socio-economic Effects; Sustainable Development; Economic Implications; Environmental Implications; Industry Practitioners; Sustainable Transportation Infrastructure Development Projects; Continuously Reinforced Concrete Pavement; Crcp; Eio-lca Model; Life Span; Construction Costs; Custom-built Economic Input-output Life-cycle Assessment Models; Rigid Pavement Alternatives; Highway Concrete Rehabilitation Alternatives; Life-cycle Assessment Approach; Social Implications; Life-cycle Assessment; Pavement; Asphalt; Pavement Rehabilitation; Environmental Assessment; Economic Factors; Land Use