Choi, Kunhee; Bae, Junseo; Yin, Yangtian; Lee, Hyun Woo. (2021). Act(2): Time Cost Tradeoffs from Alternative Contracting Methods. Journal Of Management In Engineering, 37(1).
View Publication
Abstract
Incentive/disincentive (I/D) and cost-plus-time (A+B) are two of the most widely used alternative contracting methods (ACMs) for accelerating the construction of highway infrastructure improvement projects. However, little is known about the effects of trade-offs in terms of project schedule and cost performance. This study addresses this problem by creating and testing a stochastic decision support model called accelerated alternative contracting cost-time trade-off (ACT(2)). This model was developed by a second-order polynomial regression analysis and validated by the predicted error sum of square statistic and paired comparison tests. The results of a descriptive trend analysis based on a rich set of high-confidence project data show that I/D is effective at reducing project duration but results in higher cost compared to pure A+B and conventional methods. This cost-time trade-off effect was confirmed by the ACT(2) model, which determines the level of cost-time trade-off for different ACMs. This study will help state transportation agencies promote more effective application of ACMs by providing data-driven performance benchmarking results when evaluating competing acceleration strategies and techniques. (C) 2020 American Society of Civil Engineers.
Keywords
Highway; Construction; Model; Alternative Contracting Methods; Cost-plus-time; A Plus B; Incentive; Infrastructure Trend; Time-cost Trade-off
Ho, Chung; Kim, Yong-woo; Zabinsky, Zelda B. (2022). Prefabrication Supply Chains With Multiple Shops: Optimization For Job Allocation. Automation In Construction, 136.
View Publication
Abstract
Prefabrication or off-site construction is a growing trend contributing to productivity improvements. It motivates specialty contractors and suppliers to operate multiple fabrication shops close to market regions, where a shop can produce and delivery prefabricated components in a timely fashion and at a minimal cost. Few quantitative models are available to assist companies with scheduling and allocation questions. This research utilizes optimization to answer these questions supporting the production planning in prefabrication supply chains. The paper presents an optimization model that seeks minimal cost while considering job demands and shop capacities. Computational results suggest that the model generates a lower-cost production schedule than the early due date (EDD) method. It also indicates that varying due dates cause changes in total cost. Moreover, this research supports decision-makers by analyzing the impacts of changing shop capacities regarding available machines. It provides further insight into construction supply chain management with multiple shops.
Keywords
Supply Chains; Job Shops; Supply Chain Management; Production Scheduling; Production Planning; Warehouses; Construction; Modularization; Optimization; Prefabrication; Scheduling; Off-site Construction; Modular Buildings; Scheduling Model; Precast; Management; Transportation; Performance; Decisions
Stewart, Orion; Moudon, Anne Vernez; Claybrooke, Charlotte. (2012). Common Ground: Eight Factors that Influence Walking and Biking to School. Transport Policy, 24, 240 – 248.
View Publication
Abstract
The primary goals of Safe Routes to School (SRTS) programs are to increase the number and safety of children walking, biking or using other forms of active travel to school (ATS). This study reviewed quantitative and qualitative research and identified eight common factors that influenced the choice of ATS: distance to school, parental fear of traffic and crime, family schedule constraints and values, neighborhood and family resources and culture, weather, and school characteristics. Suggestions were made as to how these barriers and facilitators of ATS could be integrated into the decision to fund local SRTS programs and to improve their effectiveness. Published by Elsevier Ltd.
Keywords
Commuting; Transportation Of School Children; Transportation Safety Measures; Qualitative Research; Cycling; Walking; Bike; Child; Pedestrian; Safe Routes To School; Safety; Walk; Active Transportation; Physical-activity; Urban Form; Elementary-schools; Safe Routes; Travel Mode; Children; Prevalence; Trip; Environment
Migliaccio, G. C.; Bogus, Susan M.; Cordova-Alvidrez, A. A. (2014). Techniques for Continuous Improvement of Quality of Data Collection in Systems of Capital Infrastructure Management. Journal Of Construction Engineering And Management, 140(4).
View Publication
Abstract
oLa infraestructura del transporte es una de las mas grandes inversiones que realizan los gobiernos. Las agencias gubernamentales de transporte administran este capital y utilizan la informacion de las condiciones de este para decidir la programacion y tipo de mantenimiento y recursos a ejercer. Para recolectar la informacion pertinente, las agencias emplean evaluadores adiestrados para evaluar la infraestructura, ya sea en sitio o analizando fotografias y/o videos. Las evaluaciones visuales son empleadas para inspeccionar las condiciones de la infraestructura, incluyendo el desgaste de la superficie de los caminos y carreteras. Este articulo describe un Data Quality Assessment & Improvement Framework (DQAIF) (Sistema de Evaluacion y Mejora de la Calidad de la Informacion) para medir y controlar los datos de los evaluadores del deterioro de carreteras, al controlar el criterio de estos. El DQAIF es en un proceso ciclico de Mejora Continua de Calidad compuesto por: a)la evaluacion del nivel de acuerdo entre evaluadores -por medio del analisis estadistico (inter-rater agreement analysis), b)la evaluacion de la consistencia a traves del tiempo -mediante analisis de regresion lineal, y c)la implementacion de practicas gerenciales para mejorar los resultados mostrados en las evaluaciones anteriores. Se llevo a cabo un estudio de caso para validar el sistema propuesto. Los resultados mostraron que el DQAIF es efectivo para identificar y resolver problemas de la calidad de los datos obtenidos en las inspecciones de infraestructura. Con este sistema se garantiza la reduccion del riesgo de la subjetividad y asi aplicar acciones de mantenimiento mas oportunas. El DQAIF puede ser empleado en un programa de gerencia de infraestructura o en cualquier programa de ingenieria en donde la informacion esta sujeta al juicio o criterio personal de los individuos que realizan la evaluacion. Este proceso puede ser adaptado, incluso, para evaluar el desempeno de sistemas automatizados de evaluacion de pavimentos.
Keywords
Manual Pavement Distress; Quality Control; Pavement Management; Inspection; Quantitative Analysis; Data Collection; Assets; Reliability; Construction Materials And Methods
El-Anwar, Omar; Ye, Jin; Orabi, Wallied. (2016). Efficient Optimization of Post-Disaster Reconstruction of Transportation Networks. Journal Of Computing In Civil Engineering, 30(3).
View Publication
Abstract
Catastrophes, such as hurricanes, earthquakes, and tsunamis often cause large-scale damage to transportation systems. In the aftermath of these disasters, there is a present challenge to quickly analyze various reconstruction plans and assess their impacts on restoring transportation services. This paper presents a new methodology for optimizing post-disaster reconstruction plans for transportation networks with superior computational efficiency employing mixed-integer linear programming (MILP). The model is capable of optimizing transportation recovery projects prioritization and contractors assignment in order to simultaneously: (1)accelerate networks recovery; and (2)minimize public expenditures. The full methodology is presented in two companion publications, where the focus of this paper is to propose new methods for (1)decomposing traffic analysis; (2)assessing the traffic and cost performance of reconstruction plans; (3)reducing the massive solution search space; and (4)phasing the use of mixed-integer linear programming to optimize the problem. An illustrative example is presented throughout the paper to demonstrate the implementation phases. (C) 2015 American Society of Civil Engineers.
Keywords
Cost Reduction; Disasters; Emergency Management; Integer Programming; Linear Programming; Project Management; Public Finance; Search Problems; Town And Country Planning; Transportation; Solution Search Space Reduction; Cost Performance Assessment; Traffic Performance Assessment; Traffic Analysis; Public Expenditure Minimization; Network Recovery Acceleration; Contractor Assignment; Transportation Recovery Project Prioritization; Milp; Mixed-integer Linear Programming; Post-disaster Reconstruction Plan Optimization; Transportation Service Restoration; Reconstruction Plans; Transportation System Large-scale Damage; Tsunami; Earthquake; Hurricane; Catastrophe; Transportation Network; Post-disaster Reconstruction Optimization; Optimizing Resource Utilization; Natural Disasters; Housing Projects; Construction; Performance; Robustness; Recovery; Plans; Transportation Network Reconstruction; Post-disaster Recovery; Multi-objective Optimization; Computational Cost; Contractors Assignment; Search Space
Coslett, Daniel E. (2017). (Re)branding a (Post)colonial Streetscape: Tunis’s Avenue Habib Bourguiba and the Road Ahead. International Journal Of Islamic Architecture, 6(1), 59 – 96.
View Publication
Abstract
Arguably Tunis's premier public space, the iconic Avenue Bourguiba is today the product of over 150 years of manipulation, regulation and interpretation. Its development can be seen as an early example of thematic place branding, thereby complicating the notion that the widespread phenomenon is an exclusively postmodern and western one. In identifying three potential place-brand labels, this article considers the establishment of the 'Parisian Colonial' Avenue by French colonial authorities, its 'Tunisian Modern' modification at independence, and its more recent historicist 'Parisian Global' refurbishment within the contexts of colonialism, authoritarian governance and globalization. On the eve of the January 2011 revolution, the space reinforced the Ben Ali regime's maintenance of control and capitalized on the long-since entrenched image of a dual - eastern and western, traditional and modern - postcolonial city. In the revolution's wake the Avenue has become a reinvigorated public forum with a more complex character. Indeed, while the Avenue's existing form and function remain emblematic of Tunis's hybrid postcolonial identity, the thoroughfare now exemplifies the ongoing 'Arab Spring'. Its cultural brandscape and heritage content, though enhanced with new aspects of democratic empowerment, are likely to endure as the transitioning country continues to participate in the process of globalization.
Keywords
Africa; (post)colonialism; Architectural/urban History; Place Branding; Heritage; Arab Spring; Tunis
Liu, Qian; Chen, Peng; Sun, Feiyang. (2018). Parking Policies in China’s Metropolises: Rationales, Consequences, and Implications. Urban Policy & Research, 36(2), 186 – 200.
View Publication
Abstract
Metropolises in China, a rapidly motorizing nation, are confronted with the challenge of managing parking pressures. Given the generally increased affordability of cars, most local authorities are making efforts to provide more parking spaces to accommodate additional cars. Although the worldwide paradigm of managing parking is shifting from a supply-focused approach to a restraint mind-set, China has been slow to follow this trend. To untangle the factors that contribute to delays implementing desirable parking policy reforms, this paper examines the development of parking policies in China. This paper characterizes the challenge of parking in Chinese cities as a spatio-temporal mismatch. In the context of rapid motorization, local authorities are subject to political pressure to cater to the increased parking demand by increasing the minimum parking requirements. However, this approach fails to mitigate parking shortages and results in unintended consequences, including relatively high parking density in central and transit-rich areas and imbalanced parking across neighbourhoods. This paper suggests four strategies, including market-based pricing, geographically differentiated supply regulations, and district-based parking management (Parking management is referred to as various policies and programs that result in more efficient use of parking resources). These strategies represent policy-reform targets to establish more efficient parking systems in rapidly motorizing urban settings worldwide.
Keywords
Parking Facilities; Urbanization; Parking Lots; China; Minimum Parking Requirements; Motorization; Parking Policies; Parking Supply; Spatio-temporal Mismatch; Requirements; Minimum; Ownership; Future; Transportation; Cities; Pressure; Neighborhoods; Affordability; Local Authorities; Shortages; Regulation; Developmental Delays; Density; Parking; Reforms
Dunn, Peter T. (2020). Participatory Infrastructures: The Politics of Mobility Platforms. Urban Planning, 5(4), 335 – 346.
View Publication
Abstract
Much of everyday life in cities is now mediated by digital platforms, a mode of organization in which control is both distributed widely among participants and sharply delimited by the platform's constraints. This article uses examples of smartphone-based platforms for urban mobility to argue that platforms create new political arrangements of the city, intermediating the social processes of management and movement that characterize urban life. Its empirical basis is a study of user interfaces, data specifications, and algorithms used in the operation and regulation of ride-hailing services and bike-share systems. I focus on three aspects of urban politics affected by platforms: its location, its participants, and the types of conflict it addresses. First, the programming forums in which decisions are encoded in and distributed through platforms' core digital architecture are new sites of policy deliberation outside the more familiar arenas of city politics. Second, travelers have new opportunities to use platforms for travel on their own terms, but this expanded participation is circumscribed by interfaces that presuppose individual, transactional engagement rather than a participation attentive to a broader social and environmental context. Finally, digital systems show themselves to be well suited to enforcing quantifiable distributional goals, but struggle to resolve the more nuanced relational matters that constitute the politics of everyday city life. These illustrations suggest that digital tools for managing transportation are not only political products, but also reset the stage on which urban encounters play out.
Keywords
Construction; Users; Digital Geographies; Infrastructure; Participation; Platform Urbanism; Shared-use Mobility
Dannenberg, Andrew L.; Rodriguez, Daniel A.; Sandt, Laura S. (2021). Advancing Research in Transportation and Public Health: A Selection of Twenty Project Ideas from a US Research Roadmap. Journal Of Transport & Health, 21.
View Publication
Abstract
Background: Transportation policies and projects have multiple impacts on health. Research on these impacts can help promote positive and reduce adverse health consequences of decisions made by transportation agencies. Methods: In 2019 the U.S. National Cooperative Highway Research Program published a research roadmap for transportation and public health based on an extensive literature search and key informant interviews. The roadmap identified 44 research gaps and 122 research needs on a wide range of relevant topics. From this list, using pre-established criteria including specificity, equity, potential impact, and long-term usefulness, we selected 20 topics suitable for further research especially in academic settings. Results: We present the questions, context, and possible research approach for each of the 20 topics. These topics cover issues ranging from integrating equity into performance measures and developing forecasting models for active travel to incorporating health questions into routine household travel surveys and examining health impacts of autonomous vehicles. We added questions on the impacts of the COVID-19 pandemic on transportation. Discussion: This list will be useful to faculty, researchers, and students as they consider topics for research in transportation and public health. Results of research on these topics could influence transportation decisions in policy making, planning and community participation, capital programming, project design, and implementation. Future leaders of transportation agencies, transportation providers, and advocacy organizations may be more likely to consider transportation policies that incorporate a health perspective if their training includes research findings that increase their awareness of the health impacts of these policies.
Keywords
Public Health; Equity; Research; Public Transit; Metrics; Transportation Planning
Choi, Suji; Kim, Soyeon; Kwak, Mingi; Park, Jaewan; Park, Subin; Kwak, Dongjoon; Lee, Hyun Woo; Lee, Sangwon. (2022). Would You Trust Driverless Service? Formation Of Pedestrian’s Trust And Attitude Using Non-verbal Social Cues. Sensors (14248220), 22(7).
View Publication
Abstract
Despite the widespread application of Autonomous Vehicles (AV) to various services, there has been relatively little research carried out on pedestrian-AV interaction and trust within the context of service provided by AV. This study explores the communication design strategy promoting a pedestrian's trust and positive attitude to driverless services within the context of pedestrian-AV interaction using non-verbal social cues. An empirical study was conducted with an experimental VR environment to measure participants' intimacy, trust, and brand attitude toward AV. Further understanding of their social interaction experiences was explored through semi-structured interviews. As a result of the study, the interaction effect of social cues was found, and it was revealed that brand attitude was formed by the direct effects of intimacy and trust as well as the indirect effects of intimacy through trust's mediation. Furthermore, 'Conceptual Definition of Space' was identified to generate differences in the interplay among intimacy, trust, and brand attitude according to social cues. Quantitative and qualitative results were synthesized to discuss implications considering the service context. Practical implications were also addressed suggesting specific design strategies for utilizing the sociality of AV.
Keywords
Pedestrians; Nonverbal Cues; Consumer Attitudes; Social Attitudes; Social Interaction; Attitude (psychology); Autonomous Vehicles; Brand Attitude; Driverless Service; Intimacy; Pedestrian–av Interaction; Social Cues; Trust; Pedestrian-av Interaction; Conversational Agent; Brand Experience; Impact; Automation; Perception; Disclosure; Style; Gaze