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The railway is indeed one of the main transportations means in the world. However, with the rapid development and advancement of the railway industries, more railways accidents occur mainly due to its defects which result in economic losses. Traditionally, the railway defect detections process which is deems to be dirty, difficult and dangerous are done manually by the railway maintenance workers. In the recent years, many sophisticated equipment such as portable detectors, track inspection trolleys, track comprehensive inspection vehicles, etc had been developed. This article outlines two main mode of inspection namely static and dynamic inspection, which are commonly used in the railway defect detection and maintenance work. Furthermore, the railway inspection equipment used by the major countries are summarized and the impact on railway inspection based on deep learning and artificial intelligence are appropriately predicted.

Constraint is a limitation of a situation, agency, or force that obstructs movement toward a goal or purpose. There are several sorts of constraints that might impact building projects. During the early phases of a project, constraints should be recognized and explained in as much detail as possible, so that knowledge of them and their potential impact can be handled. The aim of this study is to identify types of constraints that might occur in the construction industry which may affect the time, cost and scope of the project. The study was carried out on the basis of a literature review with the result and findings of previous researchers. The result and findings from the previous researcher have been analysing in the table together with the method of analysis that being used by them in order to carry out the study. From the review, it can be summarized that the key of constraints can be divided into five major elements. There are Environmental constraints, Legal Constraints, Environmental Constraints, Technical Constraints and Social Constraints. Therefore, by doing this investigation, it will help to give a better solution and performance in term of time, cost and scope of the project by classifying and limiting the constraints in the construction industry especially at an early stage in the project planning and schedule.

Urban population of Malaysia is stated as 72.8% of its total population, and growing every year. Due to this growing number of population, the sewage sludge waste produce every year has also gradually increased. Malaysia itself produces 3.2 million m3 of sewage sludge annually. Normally all of this waste is disposed by landfill. Furthermore, usual production of cement and sewage sludge ash consumes a lot of energy by using incineration process with a very high temperature. Thus, microwave heating method was an alternatives use in this research to reduce the consumption of energy and time used to heat the sewage sludge ash. This research was conducted to investigate the optimum performances of different percentage (0%, 5%, 10%, 15% and 20%) by weight of cement of the Microwaved Sewage Sludge Ash (MSSA) concrete with different curing regime, which was air and water curing. The characteristic of MSSA was tested by X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The mechanical properties of MSSA concrete was examined by Compressive Strength test, Flexural Strength test and Modulus of Elasticity test after 180 days of curing. The MSSA samples were also tested with water absorption test to evaluate the quality of concrete in term of porosity and permeability. Water curing sample with 5% of MSSA (W5) had the best in results compared to other specimens. The mechanical properties of W5 content in concrete shows the most optimum samples due to the densification of pozzolanic reaction and filler effect of MSSA. The curing effect with better result was water curing, as it got highest value of strength in compressive test, flexural test and modulus of elasticity test. As conclusion, based on the results, it is shown the positive impact on using the MSSA as additional material to the cement mixture to improve the quality of the concrete. Thus, this will reduce the disposal of sewage sludge waste on dumping site and improves the quality performances of the concrete.

Delay is a worldwide problem which normally occurs in every project. Delay of the project occurs when a period of time of the completion date is late or postponed. Since the project is delayed, the cost of the project will have escalation which will risk the contractors. Instead of getting a benefit from the project, they gain losses. Similarly, other construction projects in different countries are prone to face delays. The aim of this study is to summarise the causes of delay in the construction project from previous study. Regarding the causes of construction project delay, the major countries in the world have faced slow decision making, poor site management and supervision, shortage of labour, changes of scope of work during construction, late in revising and approving design documents, etc. The identification of important delay causes helps a contractor to plan well before the project start.