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In this study, a knowledge-based system has been developed for selection of non-conventional machining processes using a hybrid multi-criteria decision making Method. This approach is a combination ofDEMATEL(Decision Making Trial and Evaluation Laboratory),ANP(Analytic Network Process) andVIKOR(VlseKriterijumska Optimizacija I Kompromisno Resenje, in Serbian, meaning Multi-criteria Optimization and Compromise Solution) methods which evaluates different types of quantitative and qualitative measures of performance and economic factors, and ultimately provides a set of capable processes in order of priority. Twelve machining processes, eight group of workpiece material and eighteen shape features have been investigated in this study. What separates this approach from others is that, this hybrid method considers the influence of factors in the network relation map as well as their relative importance. Moreover, unlike other popular ranking methods such as TOPSIS (Technique for Order Preference by Similarity to the Ideal Solution), it is not just based on two reference points, namely ideal and inferior points; instead, it proposes a compromise solution and not just a single ranking score. Observations have shown that the developed system works satisfactorily, yields acceptable results and makes accurate decisions as well. It also provides a comparative study among the alternative processes by utilizing graphical features for better analysis and judgment of acceptable alternatives.

Mortar is a workable paste essential in civil and building construction. Mortar works as binding material extensively use for masonry unit in construction. The global consumption of natural sand is very high, due to the extensive use of concrete or mortar. Natural sand deposits are being depleted and causing a serious threat to the environment as well as the society. Sandy clay has been widely use in preparing the mortar for masonry work. The aim of this research was to study the bending strength of built-up masonry prism using sandy clay mortar. There were two series of mortar containing 0% and 100% of sandy clay had been prepared. The sandy clay was used to replace natural fine aggregate. Mortar with 0% sandy clay was the control mix containing 100% natural fine aggregate. Three types of masonry unit consist of clay brick, cement brick and lightweight brick were used in this study. The masonry units were combined together using the mortar joints to form the masonry prisms. 100% natural fine sand and 100% sandy clay mortar were prepared and used for the joints. Built-up masonry prisms with single and double joints of mortar. Also, the masonry prisms contained from a length ranging from 390 mm to 610 mm were prepared using the mortar joints. The thickness of the mortar joint which was used in this study was 10 mm, 20 mm and 30 mm. the prisms had been tested for the determination of bending strength at 28 days. The experimental results were analyzed to investigate the effect of sandy clay and thickness of mortar on the bending strength of built-up masonry prism. Results had shown that masonry prism built with sandy clay mortar has higher bending strength compare to the fine sand mortar. Clay brick exhibited highest bending strength with sandy clay mortar which was 38.28 N/mm2and cement brick had the lowest bending strength which was 18.8 N/mm2, while cement brick achieved optimum bending strength. In addition, the highest collapse and deflection achieved by clay brick and cement brick whereas the lowest value of collapse and deflection was by lightweight brick. The highest percentage of increment in terms of collapse load was determined to be 13.73% for sandy clay mortar prism. Hence, 100% sandy clay mortar is suitable to be used in masonry works.

Coal is one of the most important sources of energy, providing for over 40% of global electricity generation. Coal fly ash (CFA) is the by-product of thermal generation of energy in coal-fired power plant. CFA has been widely employed in the construction of concrete; however, there are only a few cases in which asphalt pavements have employed coal fly ash. This paper aims to determine the performances of CFA as filler in hot mix asphalt (HMA) mixture. This study used four CFA contents as filler by weight of aggregate in the dry method, namely CFA-0, CFA-2, CFA-4, and CFA-6. The mixtures were tested for stability, flow, stiffness, moisture damage, and Cantabro loss test. The findings indicated that the stability values of asphalt mixtures containing CFA were higher than conventional mixture. In addition, incorporating CFA also improved resistance towards moisture damage and durability. As a result, it can be inferred that CFA can be employed as filler substitute in HMA mixtures.