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Most residential building owners often report problems associated with the plumbing systems. If identified at the early stages, plumbing-related defects can be easily repaired. However, if unnoticed for a long period of time, they could lead to major damages and incur a significant cost to repair. Despite the problems, studies investigating plumbing anomalies and their root causes in residential buildings are limited. This study aims to explore plumbing defects and their potential causes, diagnosis methods and repair techniques in residential buildings.

This research used data collected through an extensive survey of both academic and grey literature. Through the content analysis, plumbing defects and the associated causes have been identified and presented in tabular format.

The study investigated the anomalies and causes in the residential plumbing system under five key sub-systems: water supply system; sanitary plumbing system; roof drainage system; heating, ventilation, air conditioning and gas system; and swimming pool. Accordingly, some of the identified plumbing defects include leakages, corrosion, water penetration, slow drainage and cracks. Damaged pipes, faulty equipment and installations are some of the common causes of the anomalies. Visual inspection, hydrostatic pressure test, thermography, high-tech pipe cameras, infrared cameras, leak noise correlators and leak loggers are techniques used for diagnosing anomalies. Reactive, preventive, predictive and reliability-centred maintenance strategies are identified to control or prevent anomalies.

The findings of this research can be used as a useful tool or guideline for contractors, plumbers, facilities managers and building surveyors to identify and rectify plumbing system-related defects in residential buildings.

THESE notes have been prepared because it is a fact that there is no publication available to the ordinary aeroplane mechanic which gives him the essential information which will guide him in the overhaul and maintenance of hydraulic equipment. There are only one or two books which even touch on the subject other than the official (and very excellent) R.A.F. publication, A.P. 1803.

Given below are details of certain recent developments of interest to the paint‐using industries. These are additional to the many references to new paint materials in past issues of ‘Corrosion Technology’.

This study aims to develop a decision support tool to improve planning for the rehabilitation of water distribution networks (WDN) using the analytical hierarchy process (AHP) method and the urgency level score.

In this paper the AHP method was used to outclass the indicators having a strong influence on the deterioration of the pipes and the score of the level of urgency is calculated to establish the rehabilitation program (short, medium and long term). The proposed model was tested for the case of the city of Souk-Ahras in Algeria.

Based on the judgments of twenty-four experts, the relative weights of the three physical, operational and environmental criteria of the pipeline were calculated and found to be equal to 35.40%, 55.60% and 9.00%, respectively. The two indicators, number of failures and pressure, were found to have the highest overall weights. The results of this article can be used to improve decision-making in WDN rehabilitation planning in Algeria.

The main objective of water companies is to provide citizens with good quality drinking water in sufficient quantity. However, over time, WDN age, degrade and deteriorate. This degradation leads to a drop in the performance through the degradation of water quality and an increase in loss rates. WDN rehabilitation is one of the most widely adopted solutions to address these drawbacks.

Application of a hybrid method (AHP- Level of Emergency) for the planning of the rehabilitation of WDN in Algeria.

This chapter discusses the application of fuzzy cognitive map (FCM) modelling to construction management (CM) challenges and problems. It focuses on the critical issue of managing the complexity and uncertainty inherent in CM by providing a new intelligent layer that enhances classical approaches to construction modelling and management. It investigates how the myriad types of internal and external factors affecting the feasibility and performance of construction projects can be modelled using a fuzzy hybrid method that explores the complex relationships among many contributing factors and assesses and evaluates their impacts on past and future projects. This chapter proposes a hybrid modelling approach in the traditional context of cost, schedule and risk management and describes how augmenting and enhancing existing state-of-the-art tools and processes in CM can assist construction managers. This chapter provides a background on the theory of FCMs, presents foundational and current research, and explains how to apply this approach in the CM domain. This chapter also provides a detailed description of how to develop, modify and employ interactive models to specific CM challenges and problems. It includes a customisable, interactive base model and demonstrates how the model has been applied to specific CM events and issues. Examples are presented that highlight the interplay between project-specific goals and characteristics and the way these impact the interrelated and often opposing triad of cost, schedule and risk. The presented examples and practical applications make this state-of-the-art approach useful to both academic and industry practitioners.

Despite long-term, sustained research and industry practice, predicting construction labour productivity (CLP) using existing factor and activity modelling approaches remains a challenge. The purpose of this paper is to first demonstrate the limited usefulness of activity models and then to propose a system model approach that integrates factor and activity models for better prediction of CLP.

The system model parameters – comprising factors and practices – and work sampling proportions (WSPs) were identified from literature. Field data were collected from 11 projects over a span of 29 months. Activity models based on the relationship between CLP and WSPs were created, and their validity was tested using regression analysis for eight activities in the concreting, electrical and shutdown categories. The proposed system model was developed for concreting activity using the key influencing parameters in conjunction with WSPs.

The results of the regression analysis indicate that WSPs, like direct work, are not significantly correlated to CLP and fail to explain its variance. Evaluation of the system model approach for the concreting activity showed improved CLP prediction as compared to existing approaches.

The system model was tested for concreting activity using data collected from six projects; however, further investigation into the model’s accuracy and efficacy using data collected from other labour-intensive activities is suggested.

This research establishes the role of WSPs in CLP modelling, and develops a system modelling approach to assist researchers and practitioners in the analysis of productivity-influencing parameters together with WSPs.

In 1923 Harry Crook of Bristol pioneered the manufacture of a new type of twisted wire brush, and, copying an American idea, marketed his product using a door‐to‐door selling technique. Today the firm he founded, Kleeneze, still 100 per cent British, has a turnover of £11 million, employs a staff of 600, and, is expanding fast. Today, Kleeneze's profitability lies foremost in the manufacture and marketing of products for industry, particularly brushstrip. Moreover with sales in 14 countries, a factory in Virginia, USA, a company in France and another one planned in Germany, the export potential is very promising.

This paper aims to increase the integrity of the planning process with the executive process by simulating the Last Planner System (LPS) technique using building information modeling.

A five-dimensional model was prepared, and after specifying the number of physical conflicts on the plans, all the scenarios of the starting points in the expert contractors’ plans were analyzed. Accordingly, the best scenario was determined by LPS technique. To assess the performance of the study, it was implemented on several tasks of a construction project.

The results of this research indicate that if this method is used in the planning process, the time conflicts between the expert contractors who are in the critical path are reduced, and the total delay of the scheduled time reaches zero. In addition, the conflicts between contractors whose suspension will cause no incentive and increase the daily cost overruns will reduce to the lowest point.

By simulating LPS in the planning process, time-physical conflicts are considered at the lowest point. Using this approach, conflicts are detected before the execution process, resulting in a significant reduction in the delays and cost overruns in construction projects.

The management of materials consists of an important analysis for industries as there are factors in several areas that should be considered. For this, it should take into account logistical factors, quality and production, because one piece delivered in a large lead time or outside the technical quality standards, imply delays in the project or rework. In this context, the importance of creating a control method of input and output of tools in an aviation industry in the city of Toulouse, France, was seen due to the amount of many incomplete arrivals or inappropriate material for use. The paper aims to discuss this issue.

This study used a philosophy of lean manufacturing tools and visual management (VM). A VM panel with information documents of all tools used in an assembly station of a model airplane was applied. With all data collected to carry out the project, the panel was created with the most relevant information of each tool and applied to an assembly station. That done, the production supervisors, mechanical and electrical supervisors were trained in the operation. Despite a change of management, it was realized that all supported the change due to the ease of understanding of the method and a good VM.

At the end of the work, materials management became more simplified, operators were more satisfied because of the non-occurrence of tools mistakes and the control time decreased from 120 to 15 minutes.

The application of this project has begun in an assembly station; however, it has been validated to be applied throughout the facility and its applications are being studied for other industries with different models.

This project developed a visual panel for support visual communication of the airplane assembly line. Its usage eliminates tools lost, inefficiencies and decreases lost time with tools selection.

This work proposes a way to simplify the management tools for assembly station plane using a VM panel based on the lean philosophy. The study was conducted at the Final Assembly Line of an aircraft model from a unit of an aircraft company.

This study aims to propose a hybrid simulation approach for site layout and material laydown planning in construction projects considering both the project’s continuous and discrete state.

Efficient site layout planning (SLP) is a critical task at the early stages of the project to enhance constructability and reduce safety risks, construction duration and cost. In this paper, external and internal conditions affecting SLP gets identified. Then dynamic features of project conditions and project operations are analyzed by using a hybrid simulation approach combining continuous simulation (CS) and discrete event simulation (DES).

An efficient site layout plan regarding the project conditions results in cost efficiency. Instead of using DES or CS alone, this paper uses a hybrid simulation approach. Such a hybrid method leads to more accurate results that enable construction managers to make better decisions, such as material management variables. The proposed approach is implemented in a real construction project (i.e. earthmoving operation) to evaluate the hybrid simulation approach’s performance.

The proposed approach is implemented in a real construction project (i.e. earthmoving operation) to evaluate the performance of the hybrid simulation approach.

Although DES is used widely in construction simulation, it involves some limitations or inefficiencies. On the other hand, modeling resource interactions and capturing the construction project’s holistic nature with CS or system dynamics face some challenges. This study uses a hybrid DES and CS approach to enhance commercial construction projects’ SLP.