Performance of sludge palm oil combustion using waste oil burner

Sludge palm oil (SPO) is one of the wastes produced during the activity of palm oil milling process. The most common method to synthesise biodiesel from SPO is through a chemical process known as esterification and transesterification. The chemical process required additional cost and time. Hence this paper aims to evaluate the utilisation of SPO directly as fuel in burner system and compare with conventional diesel. The SPO studied contain free fatty acid (FFA) content about 30 %, density and viscosity at 0.982 g/cm3 and 67.76 mm2/s respectively which is higher than diesel. The maximum combustion temperature achieved was 869 °C lower than diesel, 891 °C. Lower CO, CO2 and NOx emission during combustion compare to diesel around 34 %, 6% and 90 % reduction respectively. The low combustion temperature, flame length and emission due to the high viscosity of SPO compare to diesel. Fuel spray and flow was affected by viscosity which lowers the combustibility and consumption of SPO. SPO show great properties and combustion performance as fuel for burner system and improvement can make it even better

Water content determination of steam generated water-in-diesel emulsion

Emulsion fuel is one of the prevalent NOx and PM reducing techniques in compression ignition engines. An alternative method to produce emulsion is by mixing steam into diesel involving the condensation of water in the immiscible diesel. The converted steam into water, however, is difficult to determine. Hence, this paper describes a method of estimating the water content of the produced emulsion by using heat balance and Jakob’s number equations. Experiments were performed by using a custom designed 250 ml glass column, where final temperatures of the emulsion were recorded, and distillation of the sample was performed to analyze the water content. The results were compared with the equations where Jakob’s number model delivers a closer estimate of the experimental values (maximum difference 5.90%) than the heat balance equation (maximum difference 7.93%)

Zero-One matrix on Tudung Saji pattern via image processing

Pattern recognition is a method for classifying or describing the quantitative measurement of features of any object, data, or source. It involves any input that depends on the context of the study, such as biometric data, sensor data, signals, images, and so on. Prior research had been conducted on tudung saji, with a particular emphasis placed on ethnographic research that was related to group theory. In order to advance the study of the relationships between tudung saji and group theory, additional analysis is undertaken to examine the pattern of tudung saji within certain finite matrix rings. This analysis involves studying the zero-one matrix that is obtained through image processing. It is important to understand the process of pattern recognition to produce the output as a classification result from the feature extraction of the input. The study focuses on the stages of image preprocessing, which include scaling, grayscale conversion, and thresholding. The binarization image is classified through feature extraction using the image of tudung saji patterns. The binarization image produces a binary value. The threshold value is calculated by using the Otsu’s Method. This method evaluates the binary value by comparing the threshold value with the grayscale value. The result assists researchers in the subsequent classification of tudung saji patterns into group theory by means of analysing the finite zero-one matrix. Hence, the classification of tudung saji patterns can be achieved by utilising finite zeroone matrices, which allows for a more comprehensive analysis of these patterns from the standpoint of group theory. In light of these considerations, a mathematical analysis is conducted on the patterns of tudung saji under the field of pattern recognition. In this analysis, the image of the tudung saji pattern serves as the input for data processing, resulting in the production of a finite zero-one matrix

Classification of n-th order limit language in formal language classes

The study of splicing systems and their language has grown rapidly since Paun developed a splicing system known as a regular splicing scheme that produces a regular language. Since then, the researchers have been eager to classify the splicing language into certain classes in the Chomsky hierarchy, such as context-free language, contextsensitive language and recursive enumerable language. Previously, the study on the nth order limit language was conducted from the biological perspective to the limit language produced. Still, no research has been done from the generation of language point of view. This research presents a generalization on the type of classes of the formal language, the n-th order limit language. The cases to obtain the n-th order limit language are revisited and used to obtain the types of language classes according to the Chomsky hierarchy produced by the n-th order limit language

STUDENTS’ PERCEPTIONS OF COMPUTER-BASED LANGUAGE TEST (CBLT) AND VALIDATION OF CBLT-LISTENING QUESTIONNAIRE USING EXPLORATORY FACTOR ANALYSIS

Background and Purpose: One of the difficulties that emerged during online learning was the teaching and learning of listening skills which prompted the development of an online platform, Computer-based Language Test (CBLT), to assist educators conduct listening practices and assessment with students without experiencing geographical limitations. As this is a novel platform, this paper intends to examine students’ perceptions of listening skills and online learning after utilising this platform using the developed CBLT-Listening Questionnaire.   Methodology: This cross-sectional quantitative study employed questionnaires to collect data from diploma students. Two-stage sampling was utilised whereby the first stage used stratified random sampling in selecting classes from twenty-three (23) branches of the university. Simple random sampling was practised in the second stage which yielded 410 responses. The data were subjected to descriptive and exploratory factor analyses (EFA) in SPSS.   Findings: Descriptive analysis revealed that the respondents find listening a difficult skill to acquire yet view CBLT an excellent initiative for online distance learning. EFA revealed that the items in the Listening construct were significant and to be retained. However, the EFA results reported that one item from the Online Distance Learning construct needs to be deleted from the questionnaire.   Contributions: The validated CBLT-S Listening Questionnaire serves as an instrument to investigate the impact of a novel online platform (CBLT) on students' perceptions on listening and online learning. The results from this study evidenced that online platforms that incorporate practices and assessment are viewed positively by students for pedagogy in language teaching.   Keywords: Computer-based language test, exploratory factor analysis, listening skill, online listening test, CBLT-listening questionnaire.   Cite as: Khairuddin, Z., Anuar, N., Azhari, M. A., Serip Mohamad, N. H., Mohd Daud, K., Ahmad, A. R., & Abd Rashid, M. H. (2023). Students’ perceptions of Computer-Based Language Test (CBLT) and validation of CBLT-listening questionnaire using exploratory factor analysis.  Journal of Nusantara Studies, 8(2), 222-241. http://dx.doi.org/10.24200/jonus.vol8iss2pp222-24

Solution for nonlinear Duffing oscillator using variable order variable stepsize block method

Real life phenomena found in various fields such as engineering, physics, biology and communication theory can be modeled as nonlinear higher order ordinary differential equations, particularly the Duffing oscillator. Analytical solutions for these differential equations can be time consuming whereas, conventional numerical solutions may lack accuracy. This research propose a block multistep method integrated with a variable order step size (VOS) algorithm for solving these Duffing oscillators directly. The proposed VOS Block method provides an alternative numerical solution by reducing computational cost (time) but without loss of accuracy. Numerical simulations are compared with known exact solutions for proof of accuracy and against current numerical methods for proof of efficiency (steps taken)

Stability analysis of multirotor drone with water jet payload

Multirotor stability is achieved when all rotors generate equal trust to stay hovering and throttle mode. It's required the control system algorithm for propulsion speed adjustment, which is related to translational vector and rotation angle. Even with external disturbance, control system algorithm can adjust tilting angle to stabilize quadcopter. Therefore, this study focuses on developing quadcopter with waterjet system and datalogging to analyse the flight stability. It is developed with quadcopter configuration and integrating waterjet nozzle as a payload. The process includes frame development, propulsion sizing, speed calibration for each rotor, trim calibration, and a proportional integral derivative (PID) control tuning. For data collecting, copter is equipped with data storage to store flight log in form off log file. Quadcopter is test flight outdoor to embraced wind factor. The data logger shows quadcopter tilting at certain angle cause by external forces created by waterjet

DESIGN AND DEVELOP LOW-COST DEVICE FOR MONITORING OCCUPATIONAL NOISE EXPOSURE TOWARD WORKERS IN FACTORY

Occupational noiseexposure towards workeris amajorproblem related to health and safety. Itcan be annoying and affects the worker’s concentration and health during the working hours. Environmental stresssuch as occupational noise exposure from factories and industrial sites are well known with a harsh environment. This occupational noise pollutionsuch as heavy machinery noise, high number of large vehicles in and out of the sites which causing undesirable situation as a good working environment. However, the undesired noise exposure also will lead tocauses hazard and unhealthy environment at the workplace. Hence, this studydone as a solution for this problem where at least decreased the level of problems effect towardsworkers and increasethe company performance. The purpose of thisstudyis to design and develop low-cost device on monitoring occupational noise exposure named (LCDONE). This LCDONEconsist of programming for Arduino Wi-Fi UNO based ESPDuino-32 with integrated with IoTanalytics platform service ThingSpeak to gathered real time data monitoring. The data collection will be shown in decibel (dB)throughout the ThingSpeak Viewerand hasbeen validated with the established sound level meterRS PRO RS-95 with the average percentage of error for LCDONE from this study is 2.52%.The selected factory for this study and testing LCDONE was in Palm Oil Mill located in Kota Samarahan, Sarawak, Malaysia

Effect of different types of mulching on soil properties and tree growth of Magnolia champaca planted at the Montane Rainforest in Cameron Highlands, Pahang, Malaysia

Tropical Montane Cloud Forest (TMCF) is among the most vulnerable habitats to fragmentation, deforestation, and global climate change. A successful restoration program requires a comprehensive understanding of variables influencing seedling efficiency. This study was conducted on Sg. Terla Forest Reserve Cameron Highlands, Pahang, Malaysia. In this study, we used a randomized complete block design (RCBD) and measured the Magnolia champaca height, root collar diameter, diameter at breast height, plant survival, root diameter, main root length, lateral root length, root coiling, root direction, and chlorophyll content. The soil samples were taken to study the effect of different mulching materials on soil characteristics. We also measured soil compaction, soil texture, soil colour, soil moisture content, soil organic carbon, total nitrogen, total sulphur, available phosphorus, and exchanged potassium. This study indicates that mulching had no significant effect on plant height, diameter breast height, root collar diameter, and chlorophyll content between treatments. Although mulching had a significant effect on root diameter, main root length, and root distributions among treatments while for lateral root length and root:shoot ratio did not show a significant effect among treatments. However, oil palm mulching treatment had a greater effect on plant height, root collar diameter, and diameter at breast height growth, among treatments. Mulching significantly affected soil pH, soil moisture content, total sulphur, and potassium exchange. In contrast, mulching did not significantly affect soil organic carbon, total soil nitrogen, and soil available phosphorus between treatments

Microhabitat and microclimate preferences of anuran species inhabiting restoration and adjacent forest of Cameron Highlands, Pahang Darul Makmur, Malaysia

The conversion of forests to agricultural farmland modifies lands into small patches, making amphibians more susceptible to external environmental changes. It is important to restore the forest ecosystem so that fauna species, especially anurans, could gradually recover and help create a balanced ecosystem in the restoration process. The aims of this study are to determine diversity, richness, and evenness of the anuran species, and to investigate the relationship of the anuran species with environmental variables of restoration areas and adjacent forests of Terla Forest Reserve (FR), Cameron Highlands, Pahang. The study recorded 14 species belonging to six families with higher species diversity, whereby the Shannon Wiener (H’) value in the adjacent forest (H’ = 1.71) was higher as compared to the restoration area (H’ = 0.77). The anuran species in the restoration area showed an adaptation to bare soil, herbs, and shrubs. Meanwhile, in the forest, forest litter was favoured by the anuran species. Species abundance demonstrated correlation towards microclimate. The adaption of two species to the restoration area showed that temperature had a significant and negative correlation with Duttaphrynus melanostictus; relative humidity was significant and positively correlated with Polypedates leucomystax; while relative humidity had a significant and negative correlation with Microhyla annectens, a forest specialist. A deeper understanding of environmental factors that affect the presence of anurans, especially in restoration areas, can facilitate forest management in evaluating the effectiveness of forest restoration in this region