Kim, Yong-Woo; Ballard, Glenn. (2010). Management Thinking in the Earned Value Method System and the Last Planner System. Journal Of Management In Engineering, 26(4), 223 – 228.
View Publication
Abstract
Management theory has been neglected in the construction industry, which has rather focused on best practices. This paper investigates the theories implicit in two prevalent project control systems: the earned value method (EVM) and the last planner system (LPS). The study introduces two fundamental and competing conceptualizations of management: managing by means (MBM) and managing by results (MBR). The EVM is found to be based on MBR. However, project control based on MBR is argued to be inappropriate for managing at the operational level where tasks are highly interdependent. The LPS is found to be based on the MBM view. The empirical evidence from literature and case study suggested that the MBM view is more appropriate to manage works when it is applied to the operation level where each task is highly interdependent.
Keywords
Last Planner System (lps); Management Thinking; Performance Measures; Project Control
Karvonen, Andrew; Yocom, Ken. (2011). The Civics Of Urban Nature: Enacting Hybrid Landscapes. Environment & Planning A, 43(6), 1305 – 1322.
View Publication
Abstract
Urban nature is typically managed through top-down, bureaucratic, and expert-driven approaches that tend to rationalize and simplify the interactions between humans and their surroundings. In the last few decades, there has been a significant push in cultural geography and the design disciplines to develop a relational ontology of urban nature, a perspective that emphasizes the hybrid connections between humans and nonhumans, built and unbuilt, social and natural. This perspective offers new and exciting ways of conceptualizing urban nature but it has not produced alternatives to conventional governance. In other words, thinking differently about urban nature has yet to produce different ways of interacting with it. In this paper we argue that civic environmentalism can enact a relational ontology by engaging urban residents in processes of democratic deliberation and action in the reworking of urban nature. We illustrate this approach with a case study of a community-led project to construct a pedestrian trail along an urban creek in Seattle, Washington. The example demonstrates how the concept of civic environmentalism embraces a relational perspective of urban nature, while also producing generative forms of political action.
Keywords
Cities & Towns; Ontology; Deliberation; Environmentalism; Trails; Rivers; Washington (state); Seattle (wash.)
Kondo, Michelle C.; Rivera, Rebeca; Rullman, Stan, Jr. (2012). Protecting the Idyll but Not the Environment: Second Homes, Amenity Migration and Rural Exclusion in Washington State. Landscape And Urban Planning, 106(2), 174 – 182.
View Publication
Abstract
Researchers are beginning to take notice of amenity migration processes and their impacts in exurban areas of the U.S. Our research explores second-home owners as contributors to processes of amenity migration. Using a mixed-method approach combining spatial data and interview analyses, we investigate both the structural and behavioral aspects of amenity migration in San Juan and Okanogan counties of Washington State. Results indicate that second-home owners' desire for privacy and escape is reflected in patterns of spatial isolation among second homes in the study area. These patterns have potentially significant ecological effects. Second-home owners also seek to protect their investments by supporting regulations which support their version of a rural idyll. Therefore, policy-makers should be wary of strategies to promote regulations which promote aesthetic rather than social and ecological function. (C) 2012 Elsevier B.V. All rights reserved.
Keywords
Land-use; Colorado Mountains; Political Ecology; Landscape Change; United-states; Gentrification; Residents; Attitudes; Growth; West; Amenity Migration; Second Homes; Mixed-method Research
Cheng, Tao; Migliaccio, Giovanni C.; Teizer, Jochen; Gatti, Umberto C. (2013). Data Fusion of Real-Time Location Sensing and Physiological Status Monitoring for Ergonomics Analysis of Construction Workers. Journal Of Computing In Civil Engineering, 27(3), 320 – 335.
View Publication
Abstract
Previous research and applications in construction resource optimization have focused on tracking the location of material and equipment. There is a lack of studies on remote monitoring for improving safety and health of the construction workforce. This paper presents a new approach for monitoring ergonomically safe and unsafe behavior of construction workers. The study relies on a methodology that utilizes fusion of data from continuous remote monitoring of construction workers' location and physiological status. To monitor construction workers activities, the authors deployed nonintrusive real-time worker location sensing (RTLS) and physiological status monitoring (PSM) technology. This paper presents the background and need for a data fusion approach, the framework, the test bed environment, and results to some case studies that were used to automatically identify unhealthy work behavior. Results of this study suggest a new approach for automating remote monitoring of construction workers safety performance by fusing data on their location and physical strain. DOI: 10.1061/(ASCE)CP.1943-5487.0000222. (C) 2013 American Society of Civil Engineers.
Keywords
Civil Engineering Computing; Construction Industry; Ergonomics; Occupational Health; Occupational Safety; Personnel; Sensor Fusion; Psm Technology; Rtls Technology; Construction Workforce Health; Construction Workforce Safety; Equipment Location; Material Location; Construction Resource Optimization; Construction Worker; Ergonomics Analysis; Physiological Status Monitoring; Realtime Location Sensing; Data Fusion; Exposure; Tracking; Demands; Sensors; System; Construction Worker Behavior; Remote Location Sensing; Work Sampling; Workforce Safety And Health
Sprague, Tyler S. (2013). Beauty, Versatility, Practicality: The Rise of Hyperbolic Paraboloids in Post-War America (1950-1962). Construction History-international Journal Of The Construction History Society, 28(1), 165 – 184.
Abstract
The hyperbolic paraboloid was relatively unknown in the United States prior to 1950 but, by 1962, it had gained widespread recognition and acceptance among practising and academic architects, structural engineers and builders. Aligning with the architectural trends and structural capabilities of the post-war era, hyperbolic paraboloids were used to construct everything from churches to warehouses and residences to gas stations. They could be constructed in many different ways and built with different materials including reinforced concrete, plywood and aluminium. The hyperbolic paraboloid became synonymous with innovation and experimentation in construction technology. This paper reviews the people and buildings that influenced the rise in popularity of the hyperbolic paraboloid forms, traces different construction practices used to build them in the post-war Americas, and tracks their emergence as a built form that characterised the American post-war era.
Keywords
Hyperbolic Paraboloid; Construction Innovation; Aluminium; Plywood; Concrete Construction; Formwork; Usa; 1950s
Duncan, Glen E.; Mills, Brianna; Strachan, Eric; Hurvitz, Philip; Huang, Ruizhu; Moudon, Anne Vernez; Turkheimer, Eric. (2014). Stepping Towards Causation in Studies of Neighborhood and Environmental Effects: How Twin Research Can Overcome Problems of Selection and Reverse Causation. Health & Place, 27, 106 – 111.
View Publication
Abstract
No causal evidence is available to translate associations between neighborhood characteristics and health outcomes into beneficial changes to built environments. Observed associations may be causal or result from uncontrolled confounds related to family upbringing. Twin designs can help neighborhood effects studies overcome selection and reverse causation problems in specifying causal mechanisms. Beyond quantifying genetic effects (i.e., heritability coefficients), we provide examples of innovative measures and analytic methods that use twins as quasi-experimental controls for confounding by environmental effects. We conclude that collaboration among investigators from multiple fields can move the field forward by designing studies that step toward causation. (C) 2014 Elsevier Ltd. All rights reserved,
Keywords
Residential Location; Methylation; Gene; Interplay; Obesity; Causality; Environment Design; Lifestyle Risk Reduction; Social And Built Environments; Twin Studies
McLaren, Brian L. (2014). Architecture During Wartime: The Mostra d’Oltremare and Esposizione Universale di Roma. Architectural Theory Review, 19(3), 299 – 318.
View Publication
Abstract
This paper examines the architecture and planning of the Mostra d'Oltremare in Naplesa national display of colonial expansion that opened in May 1940and the Esposizione Universale di Romaan Olympics of Civilization that was proposed for 1942. These two major exhibitions will be studied in relation to Italy's violent and racially motivated Imperial politics. In the first case, it will closely examine the Villaggi indigeni (Indigenous village) of Italian East Africa, a scientific re-enactment of native constructions that became a space of violence and political confinement. In the second, it will study the Villaggio operaio (Workers' village), which, just like the larger exhibition grounds, was transformed into a site of military conflict during the war period.
Chalana, Manish. (2015). Chandigarh: City and Periphery. Journal Of Planning History, 14(1), 62 – 84.
View Publication
Abstract
This article traces the history of the greenbelt of Chandigarh, India's first modernist city, designed by Le Corbusier. The zone's protection was mandated by the Periphery Control Act of 1952, although the act's contents are often misinterpreted and do not fully reflect the project team's complex vision. This work clarifies the intentions behind the Periphery's creation, and establishes its integration with the master plan. I demonstrate how ongoing transformations violate the spirit of the Periphery's original purpose, but rarely the letter of the law. I highlight ongoing conflicts whose resolution will fundamentally shape the future of the Periphery and the master plan of Chandigarh.
Keywords
Greenbelts; Urban Planning; Urban Cores; Landscape Protection; Architecture; Government Policy; Twentieth Century; History Of India, 1947-; Chandigarh (india); India; Chandigarh; Greenbelt; Le Corbusier; Modernism; Periphery; Le Corbusier, 1887-1965
Shakouri, Mahmoud; Lee, Hyun Woo; Choi, Kunhee. (2015). PACPIM: New Decision-Support Model of Optimized Portfolio Analysis for Community-Based Photovoltaic Investment. Applied Energy, 156, 607 – 617.
View Publication
Abstract
Inherent in large-scale photovoltaic (PV) investments is volatility that stems from a unique set of spatial factors, such as shading, building orientation, and roof slope, which can significantly affect both the level of risk and the return on investment. In order to systematically assess and manage the volatility, this study seeks to create a quantitative decision-support model: Portfolio Analysis for Community-based PV Investment Model (PACPIM). Focusing on residential PV systems, PACPIM determines optimized portfolios by applying the Mean Variance Portfolio theory. The model is intended to play an instrumental role in: (1) maximizing the hourly electricity output of PV systems; (2) minimizing the hourly volatility in electricity output; and (3) optimizing the risk-adjusted performance of community-based PV investment. The application and framework of PACPIM were deployed with an actual residential community consisting of 24 houses and their simulated data utilizing PVWatts (R) for estimating hourly electricity production. Results reveal that the optimized portfolios developed by PACPIM (1) increased annual electricity output of PV systems by 4.6%; (2) reduced the volatility in electricity output by 4.3%; and (3) offered the highest risk-adjusted performance among all possible portfolios based on the Sharpe ratios. This study is expected to effectively assist project owners and investors in systematically assessing their community-based PV projects and in developing optimized investment strategies. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords
Photovoltaic Cells; Rate Of Return; Electricity; Dwellings; Electric Utilities; Community-based Investments; Decision-support Model; Mean–variance Portfolio Theory; Residential Photovoltaic Systems; Solar Energy; Decision Support Systems; Investment; Photovoltaic Power Systems; Large-scale Photovoltaic Investments; Spatial Factors; Shading; Building Orientation; Roof Slope; Return On Investment; Quantitative Decision-support Model; Portfolio Analysis For Community-based Pv Investment Model; Pacpim; Residential Pv Systems; Mean-variance Portfolio Theory; Hourly Electricity Output; Hourly Volatility; Risk-adjusted Performance; Hourly Electricity Production Estimation; Community-based Pv Projects; Optimized Investment Strategies; Romanian National Strategy; Renewable Energy; Public-attitudes; Wind Power; Pv Module; Performance; Implementation; Efficiency; Form; Economic Theory; Electricity Generation; Models; Risk; Shade; Solar Collectors
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).
View Publication
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