Mamdani-Fuzzy Modeling Approach for Quality Prediction of Non-Linear Laser Lathing Process

Lathing is a process to fashioning stock materials into desired cylindrical shapes which usually performed by traditional lathe machine. But, the recent rapid advancements in engineering materials and precision demand gives a great challenge to the traditional method. The main drawback of conventional lathe is its mechanical contact which brings to the undesirable tool wear, heat affected zone, finishing, and dimensional accuracy especially taper quality in machining of stock with high length to diameter ratio. Therefore, a novel approach has been devised to investigate in transforming a 2D flatbed CO2 laser cutting machine into 3D laser lathing capability as an alternative solution. Three significant design parameters were selected for this experiment, namely cutting speed, spinning speed, and depth of cut. Total of 24 experiments were performed with eight (8) sequential runs where they were then replicated three (3) times. The experimental results were then used to establish Mamdani - Fuzzy predictive model where it yields the accuracy of more than 95%. Thus, the proposed Mamdani-Fuzzy modeling approach is found very much suitable and practical for quality prediction of non-linear laser lathing process for cylindrical stocks of 10mm diameter

AN ANALYSIS OF QUALITY CRITERIA TO DETERMINE THE IMPROVEMENT PRIORITY ATTRIBUTES

The focus of this study is on how to find out the improvement priorities for customer satisfaction. The identification, analysis, and evaluation conducted in this study is to the Voice of Customer (VoC) based on the service attributes of SERVQUAL.  To explore customer satisfaction, the survey distributed is through questionnaire developed using Kano method and Likert scale to the customers of event organizer in Selangor, especially the customers who are using their services for wedding events. While to find out what the attributes of service delivered as the elements for improvement required, the analysis conducted is through the integration of ranking level, customer satisfaction-dissatisfaction (CS-DS) values and graph, and their correlation. In this study, the statistical analysis conducted using SPSS is to construct the comparison between Kano method results against the quality attributes based on pairwise of Functional and Dysfunctional condition to find out the correlation and the relationship among the service elements identified. This study found that “The electronic service to communicate with customer (K1)” of the service attributes of “Responsiveness” is as the first priority improvement required by customer

The performance of beta type stirling engine using different fuel

Stirling engine categorized as external combustion engine which defined as a closed-cycle regenerative heat engine to perform the conversion of energy into the mechanical power. The thermal efficiency of the Stirling cycle always is the main criterion, and the literature showed its efficiency of energy conversion is consider relatively as high as the Carnot cycle. Although the Stirling engine consists of great versatility for energy sources, however still inadequate efforts were done for the development of the Stirling engine that is powered by combustion fuel, since generally the engine is fueled by renewable energy which is inapplicable by the public. Therefore, the objectives to fill up the research gaps are to simulate the operation condition of Beta type Stirling engine by manipulated the use of different fuels with the assistant of MATLAB then compared with the outcome of a reference model to validate the outcome and to acquire the optimum performance of the engine, and any index that brings a reputation for the development of the Stirling engine. Compression ratio, and the temperature of the heater that affected by the specifications of Stirling engine design and effective volume of the heater, respectively act as the major element that manipulated the final power output. A higher compression ratio of 18 and power output of 315.88 Watts can be obtained with smaller clearance between the engine primary components, besides the heater temperature that achieves 855.75 K and thermal efficiency of 64.93% is affected by the usage of appropriate combustion fuel as gasoline and bigger effective volume of the heater

A STUDY ON IMPACT BEHAVIOUR OF A NOVEL OIL PALM FIBRE REINFORCED METAL LAMINATE SYSTEM

ABSTRACT Recently, researchers and industries have shown an increased interest in, natural fibres due to their advantages compared to synthetic fibres as it is environment friendly and low cost engineering materials. Low velocity impact response of fibre metal laminate (FML) based on short oil palm empty fruit bunch fibres according to weight percentage of 0%, 10%, 20%, 30%, 50% and 60% has been investigated. The specimens were prepared and tested using impact pendulum tester according to ASTM E-23 standard. The impact resistances of the various laminates were benchmarked with monolithic aluminium. Flat wise impact energy is almost equivalent with monolithic aluminium. This work shows that this type of FML can be used as a substitute to aluminium panels

Physical-chemical properties modification of hermetia illucens larvae oil and diesel fuel for the internal combustion engines application

The use of insects as a biofuel feedstock has received limited research, and little is known about the fuel characteristics of insect biofuel. Fuel properties characterization can guide researchers focused on renewable fuel for the internal combustion engine. Therefore, this investigation focused on the physical-chemical properties modification of Hermetia illucens larvae oil (HILO) and diesel fuel blends, which could highly become an alternative renewable fuel. Five test fuel blends of HILO and diesel fuel were prepared at 0%, 25%, 50%, 75%, and 100% on a volume basis. Fuel properties such as chemical composition, density, viscosity, heating value, cetane number, and flash point of the test fuel blends were analyzed and compared to the diesel fuel. The main physical-chemical properties of HILO-diesel fuel blends were determined following the ASTM standards. Based on the results, the density, viscosity, cetane number, and flash point of the diesel fuel-HILO fuel blends were increased by 11.28%, 740.30%, 16.92%, and 86.67%, respectively, with the addition of HILO, except for the heating value reduced by 13.66%

Advancements in additive manufacturing: Innovations in direct ink writing materials and their transformative practical applications

The domain of three-dimensional (3D) printing holds limitless potential, encompassing a diverse range of materials and applications. This review offers a comprehensive exploration of the Direct Ink Writing (DIW) technique within additive manufacturing, alongside recent breakthroughs in material advancement. The purview extends to encompass DIW methodologies, graphene oxide, hydrogels, shape-memory polymers, ceramics, polymers, and composite-based materials. The discussion delves into the multifaceted potential of 3D printing materials and their prospective applications, notably emphasizing the transformative role of DIW. The versatility of DIW is showcased in various fields, including energy storage, electronics, soft robotics, and biomedical applications. Through an in-depth analysis of capabilities of DIW and the diverse materials it encompasses, this review sheds light on the promising avenues that lie ahead in the evolving landscape of additive manufacturing

Experimental analysis on the performance, combustion/emission characteristics of a DI diesel engine using hydrogen in dual fuel mode

Among alternative fuels, hydrogen has significant promise as both a fuel and a carrier of energy. Hydrogen is projected to be a key alternative fuel in the near future to meet stringent pollution standards. Internal combustion (IC) engines, gas turbine, and aerospace industries use hydrogen as a fuel because it is non-toxic, odorless with high calorific value (CV), and combustible across a wide temperature range while also being a long-term renewable and less polluting energy source. The objective of this study is to investigate the impact of using different hydrogen rations on combustion behaver, engine performance, and emission characteristics in a dual fuel compressed ignition (CI) diesel engine. The tests were performed at speeds of 1500, 2000, and 2500 rpm at difference operating conditions. Hydrogen was introduced at flow rates of 21.4, 28.5, 36.2, 42.8, and 49.6 L per minute for each load. The findings reveal that hydrogen flow rate of 21.4 l/min and 42.8 l/min gives significant impact to engine coefficient of variation (COV) and the performance of the engine. In addition, the emissions level of CO, CO2 and smoke were improved at the same flow rate. Moreover, the break thermal efficiency (BTE) has shown significant improvement at 21.4 l/min of hydrogen flow rate due to the reduction in combustion length and the movement of the combustion phasing toward the ideal phase. The use of hydrogen as alternative energy has important role as a future green energy source

Exploring the Potentials of Copper Oxide and CNC Nanocoolants

The characteristics, stability, kinematic viscosity, viscosity index, thermal conductivity, and specific heat changes of Copper Oxide (CuO) and Cellulose Nanocrystal (CNC) hybrid nanocoolants at low concentrations are investigated in this work. The hybrid nanocoolants were created using different ratios of CNC and CuO nanoparticles and compared to single nanoparticle coolants. The existence of Cu-O and other similar formations was verified using Fourier Transform Infrared Spectroscopy (FTIR). Visual examination and UV Spectrophotometry stability study revealed that the nanocoolants were stable for up to 8 weeks, with little precipitation seen for single nanoparticle coolants after 12 weeks. When tested against temperature, kinematic viscosity decreased with increasing temperature, with very minor differences amongst coolants. The results of the Viscosity Index (VI) indicated that the hybrid nanocoolant performed similarly to the basic fluid, Ethylene Glycol (EG), even at high temperatures. Thermal conductivity rose as temperature increased, with a single CuO nanocoolant and a CNC:CuO (80:20) hybrid having the maximum conductivity. Specific heat capacity measurements revealed a declining trend as temperature rose. Overall, the CNC:CuO (80:20) hybrid nanocoolant and the CuO single nanocoolant displayed improved characteristics and stability, suggesting their potential for increased heat transfer applications

Enhancing Lubrication Efficiency and Wear Resistance in Mechanical Systems through the Application of Nanofluids: A Comprehensive Review

Due to its potential to increase lubrication effectiveness and reduce wear, nanofluids have drawn substantial interest in the field of mechanical systems. Colloidal suspensions of nanoparticles dispersed across a base fluid to create nanofluids. This comprehensive study's goal is to examine recent developments, scientific discoveries, and possible applications of nanofluids in tribology. The scientific and technical characteristics of materials which move in relation to one another are the subject of the academic topic of tribology. The aim of this review paper includes a thorough investigation of phenomena like lubrication mechanism, wear and friction. Because of their unique features at the nanoscale, nanoparticles offer a special opportunity to mitigate enduring problems in tribological systems. This review critically evaluates the process utilized to create nanofluids, examines their tribological properties, and considers how they affect the effectiveness of how mechanical systems function. The higher lubrication effectiveness and wear resistance are the main points of attention. This study also investigates several methods for characterizing nanofluids to examine their behavior. The assessment also emphasizes important elements that affect the effectiveness of nanofluids, including the composition, concentration, size, and choice of nanoparticles, in addition to the choice of the base fluid. This study examines many problems and probable future endeavors within the industry, encompassing inquiries pertaining to long-term durability, and scalability. The primary objective of this review paper is to conduct a comprehensive analysis of the current state of nanofluid research within the domain of tribology. The objective is to foster further progress and encourage the extensive adoption of nanofluids as an innovative lubricating technology