C M Tam, Arthur W T Leung
Using Construction Process Simulation to Assess Productivity of Laying Water Mains in Hong Kong
Abstract: Construction process simulation is becoming a general technique in managing design and construction processes in the western world (Hossain and Chua 2009). However, there is a paucity of records on its practical application in Hong Kong and in the Greater China. Thus, it still remains as a tool for generating academic papers within the academic arena. In Hong Kong, there is a plan to upgrade 45% of the existing 7,700 km of water mains, giving a total of 3,000 km of aged water mains to be replaced in the next couples of years. In managing this sheer amount of construction works, studying its productivity is of prime importance in order to complete the works on time and within budget. This study has applied one of the simplest simulation tools, Web-CYCLONE, to assess the productivity and explore ways to optimize it. The study reveals that Web-CYCLONE is user-friendly in assessing productivity. However, it has a number of shortfalls. For example, in running two consecutive programs, the system needs to be refreshed to renew the interface and trace the charts and diagrams generated. Besides, Web-CYCLONE has the limitation of inability in identifying the critical path of a project and thus the floats cannot be considered. Web-CYCLONE is also difficult in modeling projects with complex resource involvement.
Keywords: water mains construction, construction process simulation, productivity
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Duhovnik J, Dolinsek B
Computer modeling of robotic assembling of reinforcement
Abstract: The paper describes the functional des@ of a robot system for the assembling of the
reinforcement cages for beams and columns. The robot system was developed using a graphic
simulation program. The robot cell consists of a frame structure, a supporting mechanism, two
robots for moving and assembling of rebars and stirrups, a robot for bending of stirups, a robot
for connecting of rebars and stirrups, and a storage table for delivery of rebars and laying down
of manufactured reinforcement cages.
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Cluster: papers of the same cluster (result of machine made clusters)
Class: class.software-machine (0.133666)
class.software development (0.007740)
Sound: read aloud.
Permission to reproduce these papers has been graciously provided by the University of Ljubljana. The assistance of the editor, Prof. Ziga Turk, is gratefully appreciated.
Jakob Beetz, Leon van Berlo, Ruben de Laat, Pim van den Helm
BIMSERVER.Org – An Open Source IFC Model Server
Abstract: In this paper we introduce the ongoing development of a free and open model server to persist, maintain and manage instance models of the Industry Foundation Classes (IFC) format. By using open standards, robust existing software frameworks, best practices and workflows accepted in the broader software engineering world as the basis of our framework, we hope to gain traction within the research and development community by creating a completely open reference implementation that is free to use and extend within individual research projects and commercial applications. By providing an open and extendable architecture around a robust and performant kernel we hope to be able to encourage the integration of many earlier and current efforts that have been undertaken in the field of IFC-based model processing.We describe the set of features implemented so far and give an outline of a roadmap for future developments. Some of these implemented features include: User management, up- and downloads of models, a check-out and check-in mechanism and versioning. As part of this versioning mechanism we show a tree comparison algorithm that allows the creation of version-deltas we refer to as change sets. These change sets are used to minimize the amount of traffic to and from the central repository by only communicating its differences. All server-side functionality described here is exposed through a web-service API which has been used to implement web-based and standalone client applications. A filtering mechanism allows the extraction of sub-models such as specific element types. We show how we transform original STEP part 11 EXPRESS schemas into a Meta-Object-Facility (MOF), and store them in XMI/EMF models. Furthermore, we describe how our framework provides a mapping to a BerkeleyDB database facilitating its rich set of features. We demonstrate how we use a suite of more than 1600 IFC models from various sources to test the integrity of the framework. To demonstrate that our framework works efficiently enough for real-world building model scenarios, we provide some performance indicators using this extensive suite of test models.We finish our report by laying out some of the ideas and plans for the future development of the server which include query languages (for the definition of IDMs etc.), a viewer (e.g. for the visualization of differences between model versions) and the integration of other model schemas such as the ISO 12006-3.
Keywords: IFC, model server, BIM, CAD, collaboration
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Z. Ren, L. Sha, T. M. Hassan
RFID facilitated construction material management - a case study of water supply project
Abstract: Due to the complex and dynamic nature of the construction industry, construction material management faces many unique challenges from material planning, ordering, receiving and storing, handling and distribution, site usage and monitoring (Johnston and Brennan 1996). Poor material management has been identified as a major source for low construction productivity, cost overrun and delay (Fearon 1973, Olomolaiye et al. 1998). Although many fac-tors contribute to the problems of material management, the lack of active, accurate and integrated information flow from material planning, inventory to site use and monitoring is the major contributor. However, it is difficult to obtain such accurate information actively due to the nature of the industry, particularly for large or material intensive projects such as oil or water pipe-laying projects. A Radio Frequency Identification system (RFID) facilitated construction ma-terial management system has been developed to tackle this problem. This latest technology helps the project team to collect material storage and usage in an active and accurate way, and further to facilitate the information flow through the construction material management process with focus on the dynamic material planning, ordering and monitoring. The developed system is being implemented in a water-supply project.
Keywords: RFID, construction, dynamic, material planning, monitoring
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