T. Celik, Y. Baalousha & F. Ibisevic
Developing a forecasting model for the prediction of inflation rates for use in life cycle cost analysis
Abstract: Life cycle cost (LCC) is a technique that satisfies the requirements of owners for adequate analysis of total costs. Inflation rate may be considered as one of the main parameters that may have an effect on a LCC analysis of a project. Therefore it is necessary during the life cycle cost analysis to carry out a detailed analysis and predict inflation rates for the future.This paper outlines the development of an artificial neural network model for forecasting the inflation rates for the project period. The artificial neural network back propagation algorithm is implemented by using Mat lab Package. The model trained by 25 inflation index values and tested with 25 inflation index values, by comparing the two sets, the error rates was found as 0.022. LCC spreadsheet was developed in Microsoft Excel, taking into consideration all costs that may be in-curred during the project life and predicted inflation rate.
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The LexiCon: structuring semantics
Abstract: The ISO/PAS 12006-3:2000 "Framework for object oriented information exchange" provides a metamodel
for structuring data relevant to the construction industry. The LexiCon, developed by STABU, is an
implementation of that model. The LexiCon consists of a set of concepts, grouped into categories according
to 12006-3. Each concept should be defined by a set of other concepts and is placed in a specialization
hierarchy with other concepts of the same category. Ultimately, a set of basic concepts exists, from which
all the other concepts are being derived, but which can only be described by a verbal definition.
The concepts in the LexiCon represent the language of the construction industry. The terms of this
language are extracted from numerous documents on several levels of formality, such as standards,
building codes, specification systems, product information systems, technical dictionaries and classification
systems. From these terms found in external documents concepts are then defined in the LexiCon with
formal definitions. Terms from external documents can be in any human language, thus the LexiCon will be
Putting the concepts in the LexiCon in a specialization hierarchy has been a process of trial and error, so
far. In principal, the number of possible hierarchies is endless, leading to also endless discussions. We are
now trying to use a more systematic approach, based on the idea that, when a concept is defined by a set of
other concepts, there will be a subset of these defining concepts that will dedicate where the described
concept will fit into a hierarchy. A consistent hierarchy will be obtained when the subsets of defining
concepts are subsets of defining concepts on a lower level of that hierarchy. It will then be possible to
reorder the hierarchy into another hierarchy, by using different sets and subsets of defining concepts.
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Cluster: papers of the same cluster (result of machine made clusters)
Class: class.synthesis (0.018068)
class.software development (0.012882)
Sound: read aloud.
Permission to reproduce these documents have been graciously provided by the Aarhus School of Architecture, Denmark. The assistnace of the editor, Prof. Kristian Agger, is gratefully aprecciated.
Zhuohua Huang and Aizhu Ren
A BIM Based Collaboration Platform for Data Transmitting in Building Design
Abstract: BIM (Building Information Modelling) has gradually been accepted and applied by the Chinese engineers. In the meantime, the BIM software which suits the Chinese design process and satisfies the Chinese design codes have not been developed sufficiently. To meet the requirements of BIM based collaboration platform for fluent data transmitting in building design process which suits the Chinese building design practice, this paper presents the solutions on the development of a BIM based collaboration platform. 4-layer architecture is employed to make the function of each part of the collaboration platform clearer; a 3D space for BIM models with version information is created to record the model history and allow engineers to check the version difference; the authorization and certification managing algorithms are designed to ensure an ordered work status on the collaboration platform; the lock-switches and dividing of work sets are developed to solve the object conflict problems; message sending and receiving mechanism are formulated to get fluent communications among the users who are working on the same building project. A protocol of the collaboration platform has been developed on these solutions and shows the study results.
Keywords: BIM, Collaboration Platform, Building Design, System Architecture
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