| Journal Volume 7, No 2, ISSN: 1832-8505 Date: Nov, 2012 |
| Title: A KNOWLEDGE BASED SYSTEM OF ELEMENT RECOGNITION IN 2D CONSTRUCTION DRAWINGS FOR AN AUTOMATED BILLS OF QUANTITIES |
-By Chitrakala Muthuveerappan, Anil Minhans, Abdul Hakim Mohammed and Muhd Zaimi Abd Majid
Abstract
Estimating is one of the critical success factors of a construction project. In practice, estimating is a sole activity carried out at the pre-construction phase using the construction drawings. Engineering drawing specifications, past experience, and previous records or references help the quantity surveyors to produce the bills of quantities manually. However, the estimating software available in market needs manual key-in for the drawing elements as the automation of estimating made directly from the construction drawings is critical. This is due to various issues such as no algorithm to recognise the primitive symbols of the two dimensional (2D) drawings into construction elements, random practice of drawing specifications, and lack of standardized specifications in 2D drawings. This study develops a prototype in-built with a new knowledge-based algorithm to recognize the drawing primitive symbols of lines, arcs, text and other symbols into construction elements in 2D drawings. The beam element drawing is selected randomly for this element recognition. The element recognition method follows namely i) extraction of the drawing attributes from the 2D drawing; ii) identification of the construction elements from the extracted drawing attributes; iii) classification of the construction element’s attributes into parametric values; and iv) interpretation of the parametric values into bills of quantities. The prototype has been validated with real-time commercial drawing for its element recognition performance to produce the bills of quantities. In conclusion, the prototype being developed from this research successfully produces bills of quantities through auto element recognition from the 2D drawing.
Keywords: Bills of quantities, element recognition, estimating.
| Journal Volume 7, No 2, ISSN: 1832-8505 Date: Nov, 2012 |
| Title: GIS-BASED MASS APPRAISAL MODEL FOR EQUITY AND UNIFORMITY OF RATING ASSESSMENT |
-By Ibrahim Sipan, HishamuddinMohd Ali, Suriatini Ismail, Shahabudin Abdullah and Shazmin Shareena Abd Aziz
Abstract
Rating is a major source of income for local authorities. The basis of rating is the assessed values of property holdings from which property tax can be charged. The traditional single valuation method contributes to the inconsistency of assessed values because locational factors are not considered objectively. The traditional method is also unable to produce equity and uniformity of the assessment values consistently. The main objective of this study was to develop a mass appraisal model incorporating spatial analysis and geographic information system (GIS) to produce more accurate predictions of property values and, thus, to achieve an overall equity and uniformity of property rating assessment. In order to achieve the objective, Majlis Perbandaran Kulai was chosen as a study area. The study involved 1,500 property holdings transacted between 2004 and 2006 representing 86 housing areas. The variable components for locational factors, namely accessibility, neighborhood and environment were generated using GIS spatial analysis which included buffering, overlaying, and network analysis. The outputs from the analyses consisted of variable components which were derived objectively and they can assist in the process of forming mass appraisal model. Four mass appraisal models were used as alternative choices to the traditional single valuation method. They were ordinary least squares (OLS), spatial hedonic model (SHM), geographically weighted regression (GWR), and kriging. The outcomes of the models showed that the assessed values were statistically significant. The performance of mass appraisal models from equity and uniformity perspectives was measured using ratio study technique. The four models were compared on the basis of their accuracy in terms of equity and uniformity. It was discovered that the spatial hedonic model (SHM) was the best choice followed by the ordinary least square model (OLS) as the second best choice.
Keywords: property rating, mass appraisal model, equity, uniformity, ratio study, geographic information system (GIS), spatial analysis, OLS, SHM, GWR, kriging
GIS-BASED MASS APPRAISAL MODEL FOR EQUITY AND UNIFORMITY OF RATING ASSESSMENT
| Journal Volume 7, No 2, ISSN: 1832-8505 Date: Nov, 2012 |
| Title: PROCUREMENT CONTRACT: EXPLORING THE PRINCIPLE AND ISSUE IN THE MALAYSIAN CONTRUCTION INDUSTRY |
-By Mastura Jaafar and Saieed Mohamed A. Abdelsalam
Abstract
Procuring buildings is different from procuring goods. In procuring goods, a buyer can benefit from price competition even for inferior goods with questionable quality. The scenario is different in the construction industry. The term “procurement system” which is different from “procurement contract” has been closely associated with procuring materials or buildings. The use of different terminologies motivates this study to look closely at the definitions of these terms. The literature shows that the terms “procurement system” and “procurement contract” are used interchangeably especially in the Western countries, but the term “procurement system” is more widely used by industry players in Malaysia. Despite the various terms used for “procurement contract”, in most countries, “fixed price” (FP) procurement contract has been more extensively used in the construction industry compared to “cost reimbursement” (CR). Besides, the concept of procurement contract as FP and CR, mainly used by Western economists, is also explored.
Keywords: procurement system, procurement contract, fixed price, cost reimbursement, construction industry
PROCUREMENT CONTRAC, EXPLORING THE PRINCIPLE AND ISSUE IN THE MALAYSIAN CONTRIBUTION INDUSTRY
| Journal Volume 7, No 2, ISSN: 1832-8505 Date: Nov, 2012 |
| Title: THE CAUSE FACTORS OF LARGE PROJECT’S COST OVERRUN: A SURVEY IN THE SOUTHERN PART OF PENINSULAR MALAYSIA |
-By Aftab Hameed Memon, Ismail Abdul Rahman and Ade Asmi Abdul Aziz
Abstract
Construction cost overrun has become a global concern amongst the practitioners and academic researchers because the construction projects are very rarely completed within the estimated cost limit. There are various contributing factors to cost overrun. This study focuses on cost overrun encountered in large construction projects. Data was gathered using structured questionnaire survey among clients, consultants and contractors in the states of Johor, Melaka and Negeri Sembilan of Peninsular Malaysia. Statistical methods were used to analyze the data. The survey results show that 96% of the respondents agreed that most construction projects face cost overrun with an average amount ranging from 5% to 10% of the contract sum. Investigation on the causes of cost overrun involves 35 common factors identified through the literature. Results indicate that fluctuation in materials price, cash flow and financial difficulties faced by contractors, delay in progress payment by owner, and frequent design changes were most dominant factors causing cost overrun. Spearman correlation test was conducted on the factors showing that slow information flow was highly correlated with the lack of communication between parties (with a correlation value ρ = 0.787). Standardized design practices, efficient resource planning and management and proper financial management should be considered as effective tools in controlling cost overrun especially in large construction
projects.
Keywords: Cost overrun, Causes of cost overrun, Relative Importance Index, Spearman correlation, large projects
| Journal Volume 7, No 2, ISSN: 1832-8505 Date: Nov, 2012 |
| Title: THE FUTURE USE OF UNDERGROUND SPACE IN MALAYSIA, A LITERATURE REVIEW |
-By Farah Zaini, Khadijah Hussin, Arfaliza Arrifin and Nurlaila Ali
Abstract
Today, more than half of the world population lives in urban areas and it is expected that this figure will grow rapidly to reach 85.9% in 2050. People will keep on migrating from inland to village, city, and metropolis and the number is increasing year by year. Cities are increasingly overcrowded and congested. The rapid developments in urban area to meet human needs are found to be inconsistent with the principle of sustainable development. Besides, space is highly demanded with great pressure especially for housing and infrastructure. This results in other problems such as greater traffic congestion, air pollution, and lack of green space for development. Due to these circumstances, the other consideration is using none other than going to the third dimension of city as a final frontier in urban development and possible path to sustainable urban form. In Malaysia, the use of underground space started with the establishment of shop lots below the Merdeka Square, sixteen years ago, then followed by Petronas Twin Towers, Light Rail Transit, Storm water Management and Road Tunnel (SMART), and the most recent is an ongoing project of Mass Rapid Transit (MRT). Looking on positively for the underground development for infrastructure, this paper attempts to review and discuss the present and future use of underground space in Malaysia. The paper also explores the potential planning and challenges of underground development. This is done by reviewing successful underground developments around the world in order to suggest the potential planning for underground space in Malaysia. The investigation attempts to address the possibility of developing a sustainable underground development in Malaysia as a step forward.
Keywords: urban underground space, planning and utilization, sustainable development
THE FUTURE USE OF UNDERGROUND SPACE IN MALAYSIA, A LITERATURE REVIEW