Performance of self consolidating concrete with recycled concrete aggregate / Mohd Afiq Mohd Fauzi

Self Consolidating Concrete (SCC) is an emerging class of concrete materials that offers great potential for improved ease of positioning and scaled down cost through reduced time and labour. Generally, tonnes of Construction and Demolition Wastes (C&DW) are raised daily. The situation is similar to the paper industry where large amount of the wastes or paper sludge generated every day and at the same time bringing potential and devastating harmful impact to the surroundings. For this reason, the search into the use of coarse and fine recycled concrete aggregate produced from crushed concrete waste is looked into. Many researchers had found that waste materials have unique properties that could improve the quality of self consolidating concrete produced. Nevertheless, on that point there is no study available on using Waste Paper Sludge Ash (WPSA) as cement and coarse and fine Recycled Concrete Aggregate (RCA) as coarse and fine aggregate replacement materials respectively in self consolidating concrete. Therefore, the reuse of RCA and WPSA generated as the supplemental material for the replacement of aggregate and cement are significant in reducing the environmental impact. This research was focused on the strength characteristic and the chloride permeability level of SCC containing RCA and WPSA. The influence of RCA content in the range from 0% to 100% of Natural Aggregate (NA) to the strength characteristic and the chloride permeability level of SCC containing optimum WPSA was identified and compared with SCC containing normal mixes. In this research, three (3) series of concrete specimens were cast with different water cement ratios (0.53, 0.49 and 0.45). The concrete specimens were subjected to strength at the age of 3, 7, 14, 21, 28, 56 and 90 days and durability at the age of 28, 56 and 90 days. The result indicated that the compressive strength and chloride permeability of SCC containing 100% RCA replacement give better performance than the 0% RCA replacement. Based on the finding, SCC containing 100% RCA replacement can be categorized same as a conventional concrete hence it can be utilized for construction purposes. RCA can also acts as an alternative replacement in concrete for replacing the NA

Computer Vision Estimation Of Volume And Weight Of Apple By Using 2d Noncontact Measuring Method

Apple is one of the most famous fruits that have been picked by a lot of families in Malaysia. There are several factors that determine apple quality which are volume and weight. The two parameters have been used as a benchmark to identify the quality of apples. These two parameters can be easily measured individually by using a weighing balance to measure weight and water displacement method (WDM) to measure volume. However, these two methods are not suitable to apply in industries since both methods required a lot of time to obtain the final output. Therefore, new technology is needed in order to estimate the weight and volume of apples. The main objective of this project is to develop a vision-based system that is able to estimate the volume and weight of apples. The volume of the apple is calculated by using the width and height of the apple via images. The camera needs to calibrate in order to get the ratio of pixel/cm which is used for conversion data. Detectron2 with a custom dataset will be used to detect and segment apple images. The output of detection and segmentation images will be used to create boundary boxes to obtain the height and width of apples. The developed systems are tested by four different settings which have different variables. The volume and weight of apples are able to obtain 85.41% and 85.26% of accuracy by using the formula. Overall, the project is able to estimate all the parameters of apple with an accuracy of more than 80% which can be concluded as a successful project

The implementation of teaching Science and Mathematics in English at secondary school in Kelantan / Iszam Hayati Hamat...[et al.]

Teaching of Science and Mathematics in English TeSME, more frequently referred to as PPSMI(Pengajaran dan Pembelajaran Sains dan Matematik dalam Bahasa Inggeris) is a policy involving the change of medium of instruction for these two subjects from Malay which is the National Language of Malaysia to English. The implementation of PPSMI seems to have resulted in several issues and problems that have required attention. This article reports on part of an on-going study that focuses on the demographic profiles and perceptions of learners with limited English proficiency. The purpose of the study was to find out the relationship between student’s attitude and their achievement towards learning English in mathematics and science. In implementing English language as a second language in school, normally teachers who are teach in school at rural area usually faced more problems compare to the teachers who are teach English in urban school. One of the objectives of this study to know how far that statement can be accepted and the research will handle about the problems of teaching English as a secondary language, whether the students agree or disagree about this. The result showed that the highest percentage of students disagree for the implementation of study mathematics and science in English. It can be prove by the questionnaire and question test that will be given for them

Estimation of volume and weight of apple by using 2D contactless computer vision measuring method

Volume and weight are key parameters that have been used as a benchmark to identify the quality of apples. These two parameters can be easily measured individually by using a weighing balance to measure weight and the water displacement method (WDM) to measure volume. However, these two methods are not suitable to apply in industries since both methods require a lot of time to obtain the final output. Therefore, a new approach is needed. The main objective of this work is to develop a contactless system based on computer vision system that can estimate the volume and weight of apples by using the width and height via 2D image captured. The camera needs to calibrate in order to get the ratio of pixel/cm by using the checkerboard point detection technique. Mask regional convolution neural network (R-CNN) was used to detect and segment apple images while providing the height and width of apples. The system was tested with four different settings, with 20cm and 30cm distance, and two different camera models. The best estimation of the volume and weight of apples obtained were with errors of 11.97 % and 11.49 % respectively. Overall, the findings showed that height and width from a 2D calibrated perspective can be used as an alternative method for the contactless assessment of apple volume and weight

Effect of Limestone Powder as an Additive and as Replacement of Self-Consolidating Lightweight Foamed Concrete

Concrete is the absolute most broadly utilized material in the development which must needs to guarantee attractive compressive quality and sturdiness. Mechanical properties of concrete are highly influenced by its density. A denser concrete generally provides higher strength. Numerous studies have been conducted for development of self-consolidating lightweight concrete (SCLWC) by investigating especially on their materials component and mix proportion. Commonly, considerations made by the researchers to produce SCLWC is by replacement of aggregates with alternative lightweight materials such as pumice, expanded clay, rubber granules and more or by adding foam agent. Besides, Limestone powder (LP) is one of concrete admixture that widely used as cement replacement. LP is proven can reduce energy consumption and resources from cement process, as well as effects the concrete properties. However, there are very few studies using only LP as main admixture for SCLWC. Therefore, the objectives of this study are to investigate the effect of limestone powder as an additive and as cement replacement in SCLW foamed concrete (SCLWFC) to the flowability and compressive strength. The experiment involves 3 types of SCLWFC which are normal mix; mixes without LP, additive mix; mixes with LP as an additive and replacement mix; mixes with and LP as cement replacement. Based on this study, the results indicated that the utilization of LP has positive effects to the flowability. Maximum value for slump flow was obtained when the LP as cement replacement at 40% and maximum value for compressive strength was obtained when the LP as an additive at 10%

Generation Of Q-Switched Fiber Laser At 1.0-, 1.55-And 2.0-µM Employing A Spent Coffee Ground Based Saturable Absorber

Spent coffee ground (SCG) was demonstrated as saturable absorber (SA) for Wideband Q-switched fiber lasers generation. The SCG SA has a broad linear absorption that covers from 1000 nm to 2000 nm wavelength and a modulation depth of 30% at 1.55-µm region. Through purification process, the finer SCG powder is obtained, and be embedded with a polyvinyl alcohol for thin film formation. To realize Q-switching operation lasers, a fabricated SCG film was integrated into three different fiber laser cavities including ytterbium-doped fiber laser, erbium-doped fiber laser, and thulium-doped fiber laser. A peak wavelength has obtainable at 1031 nm, 1563 nm, and 1976 nm for 1-, 1.55-, and 2- µm regions, respectively. The shortest pulse width of 4.80 µs and maximum pulse energy of 0.152 µJ are observed from the YDFL cavity. RF spectrum shows the signal-to-noise ratio for all regions is above 35 dB, indicates a stable pulsing generation. Our technique opens the door for unlimited materials SA from environmentally friendly resources which contribute to sustainable effort