Scheduling system for repetitive unit construction using lineofbalance technologyARDITI, DAVID; TOKDEMIR, ONUR B.; SUH, KANGSUK
2001 Engineering, Construction and Architectural Management
doi: 10.1108/eb021173
Although lineofbalance LOB scheduling can be superior to bar charts and networks in repetitiveunit construction, there are indications that its use is not widespread. In this study, the major limitations of the existing LOB methodology are identified and then eliminated by developing a computer program called repetitive unit scheduling system RUSS. An effective algorithm that facilitates the implementation of LOB scheduling is developed. A tool that handles logical and strategic limitations caused by the particular characteristics of repetitive activities is provided. A learning model is developed and incorporated into LOB calculations. The program is designed to optimize resource allocation by using multiples of the natural rhythm of activities. An optimum crew size that guarantees maximum productivity in an activity is used throughout the LOB calculations to achieve costoptimized schedules. Nonlinear and discrete activities are incorporated into the LOB calculations. RUSS displays the LOB diagram of every individual path in the unit network. It is believed that a system such as RUSS will make the LOB method more appealing to contractors of repetitive projects.
Neurofuzzy modelling of construction projects' duration I principlesBOUSSABAINE, A.H.
2001 Engineering, Construction and Architectural Management
doi: 10.1108/eb021174
Construction projects' duration can be modelled using traditional and artificial intelligence methods. The first part of these two papers provides an insight into the principles of modelling project durations using neurofuzzy methods. This paper presents an understanding of how these methods operate and discusses the main issues concerning their use and application in construction management. An introduction to the problems of modelling and predicting construction projects' duration is first presented. This is followed by explaining the neurofuzzy life cycle modelling process and discussing methods for modelling projects' duration. A graphical presentation of the way in which neurofuzzy methods operate is also presented and discussed.
Multiproject cash flow optimization noninferior solution through neuromultiobjective algorithmLAM, K.C.; HU, TIESONG; CHEUNG, S.O.; YUEN, R.K.K.; DENG, Z.M.
2001 Engineering, Construction and Architectural Management
doi: 10.1108/eb021176
Modelling of the multiproject cash flow decisions in a contracting firm facilitates optimal resource utilization, financial planning, profit forecasting and enables the inclusion of cashflow liquidity in forecasting. However, a great challenge for contracting firm to manage his multiproject cash flow when large and multiple construction projects are involved manipulate large amount of resources, e.g. labour, plant, material, cost, etc.. In such cases, the complexity of the problem, hence the constraints involved, renders most existing regular optimization techniques computationally intractable within reasonable time frames. This limit inhibits the ability of contracting firms to complete construction projects at maximum efficiency through efficient utilization of resources among projects. Recently, artificial neural networks have demonstrated its strength in solving many optimization problems efficiently. In this regard a novel recurrentneuralnetwork model that integrates multiobjective linear programming and neural network MOLPNN techniques has been developed. The model was applied to a relatively large contracting company running 10 projects concurrently in Hong Kong. The case study verified the feasibility and applicability of the MOLPNN to the defined problem. A comparison undertaken of two optimal schedules i.e. riskavoiding scheme A and riskseeking scheme B of cash flow based on the decision maker's preference is described in this paper.
ISO 9000 certification of Singapore construction enterprises its costs and benefits and its role in the development of the industryOFORI, GEORGE; GANG, GU
2001 Engineering, Construction and Architectural Management
doi: 10.1108/eb021177
The construction management literature discusses the benefits which companies derive from having their operations certified to the ISO 9000 series of quality management systems QMS. In Singapore, quality has been a topical issue in the construction industry for the past decade. ISO 9000 certification, which has been a major part of the construction quality development programme, is now mandatory for large construction contracting and consultancy organizations wishing to register to undertake publicsector projects. This paper reports on a study on the role which ISO 9000 implementation plays in the quality development of Singapore's construction industry by ascertaining the perceptions, objectives, motivations and experiences including benefits and problems relating to quality in general, and to ISO 9000 certification and implementation in particular. A questionnairebased survey of large construction companies was conducted. It was found that construction firms benefit from QMS certification, and face no significant problems with it. Recommendations are made for enhancing the benefits of ISO 9000 and ensuring that it has a positive longterm impact on the development of Singapore's construction industry.