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Comparison of Compression Parallel to Grain of Acacia Hybrid for Untreated and Treated at Different Combination of Age Groups
No full textSarawak's wood-based industries face challenges due to a shortage of wood-based raw materials. Research on the Acacia
hybrid species is limited, but it is crucial for the timber engineering field. Acacia hybrids have been selected for
reforestation projects due to their rapid growth. Since 2001, various license holders have planted Acacia mangium and its hybrids on over 245,000 hectares in Sarawak. The species were collected from a plantation area owned by Daiken Sarawak Sdn Bhd. Tests on physical properties, namely moisture content (MC) and basic density, were carried out. Meanwhile, tests on mechanical properties for both untreated and treated samples were also conducted, including static bending tests (modulus of rupture, MOR and modulus of elasticity, MOE) and compression parallel to the grain test. All the tested samples were in air-dry condition, with the MC ranging from 12 % to 19 %. The specimens were prepared according to BS 373:1957 and Method of Testing Small Clear Specimens of Timber. All tested results were analyzed using statistical methods to determine mean results. All the results that had been tested were analyzed using statistical analysis as mean results. Comprehensive testing of Acacia hybrid wood treated with copper chrome arsenic (CCA) has significantly improved its physical and mechanical properties. The treatment results in higher density and strength, influenced by growth and structural variations of the wood. It also enhances moisture retention, boosting the wood's hydrophobic properties and durability. Treated wood shows increased Modulus of Rupture (MOR) and Modulus of Elasticity (MOE) in static bending tests, demonstrating enhanced resistance to bending and structural integrity. Compression tests reveal that treated wood is 27% stronger than untreated, confirming its superior ability to withstand compressive forces. From this study, the best age
combination product is 10y+10y, and it can be concluded that the comprehensive testing of Acacia hybrid wood reveals
treatments enhance its physical and mechanical properties
On Ordered Weighted Averaging Operator and Monotone Takagi-Sugeno-Kang Fuzzy Inference Systems
Get PDF—The necessary and/or sufficient conditions for a TakagiSugeno-Kang Fuzzy Inference System (TSK-FIS) to be monotone has been a key research direction in the last two decades. In this paper, we firstly define fuzzy membership functions (FMFs) with single and continuous support; and consider TSK-FIS with a “grid partition” strategy for computing its firing strengths with product T-norm (here after denoted as TSK-FIS-product). We also define a more general joint necessary condition, whereby each constituent
itself is a necessary condition for the TSK-FIS-product model. The first necessary condition indicates that the normalized firing strength must not be indeterminate (i.e., 0/0), i.e. susceptible to the “tomato classification problem”. The second necessary condition indicates that all restricted consequents of fuzzy if-then rules must be defined. Based on the principle of the ordered weighted
averaging (OWA) operator as well as the concept of increasing orness in OWA and hyperboxes, a general joint sufficient condition for a TSK-FIS-product model to be monotone is derived. Three case studies of the developed methods for undertaking Failure Mode and Effect Analysis (FMEA) and image processing tasks are presented. The results are compared, analyzed, and discussed, demonstrating the usefulness of our developed methods
Experimental and Numerical Investigations on Micromixers and Micropumps for Performance Enhancement in Point-of-Care (POC) Applications
Get PDFPoint-of-care (POC) device is a medical tool for a rapid initial diagnosis of near-patient testing which suits the necessities in telemedicine. In POC devices, lamination-based passive micromixers have been largely used. This, however, requires a long mixing channel to mix fluid or bioassays completely. To overcome this, structured two-dimensional (2D) mixing channels have been introduced as an alternative to achieve the same mixing performance but with a shorter channel length. Hence, in this present study, two variants of the obstacle-based 2D passive micromixer were shortlisted, namely the T-micromixer with circular mixing channel and Tesla micromixer were introduced and fabricated to identify the best micromixer for POC application. Micromixer selection was based on the liquid mixing performance determined using the RGB method. Tesla micromixer was selected due to the capability to mix fluid completely (MI = 100%) compared to the T-micromixer with circular mixing channel (MI =57.33%) at the same Re = 40. On the other hand, passive micropumps are alternatives for conventional benchtop pumps used in POC devices due to the latter are usually placed at the micromixer inlets hence multiple units are required to drive fluids into a micromixer that has many inlets. Apart from that, running on these conventional pumps also may cause leakage in the device due to the higher working pressure than the ambient. Therefore, to cope with these shortcomings, two variations of the passive micropump were suggested, namely the multi-angle paper-based capillary (MAPC) and sub-atmospheric pressure (SAP) micropumps. They were fabricated and assessed for the selection of the suitable micropump to be used in the proposed POC unit. The micropump selection was based on the flow rate performance of the mentioned micropumps. During standalone operations, the SAP micropump has a higher flow rate (Q = 49.9 µL/s) as compared to the MAPC micropump (24.4 µL/s), thus it was selected to be integrated with Tesla micromixer in the proposed POC unit. SAP micropumps were identified to be suitable for attachment to the outlet of a micromixer for overcoming the leakage problem in tubing networks. In the final stage, the numerical investigation was done in terms of CFD simulations to optimize the gauge pressure of the integrated unit of the Tesla micromixer and SAP micropump. Optimization showed a complete fluid mixing was achieved at a gauge pressure of -10 kPa. In addition, the simulation showed that fluid mixing was caused by the generation of Dean vortices and minor chaotic advection at each valve stage. It was also identified that the actual gauge pressure was lesser than the simulated gauge pressure, and found to be diminished with time due to the physical limitation of the micropump chamber. In overall, the mixing performance between the simulation and experiment compares well despite the deviation of about -0.51 kPa, and demonstrates the viability of the proposed POC unit for enhanced fluid mixing
Isolation and Identification of Fungi in Raw Wet Sago Starch from Sarawak
Get PDFSago starch is a type of carbohydrate source which, extracted from the pith of Metroxylon sagu (true sago palm) and is a traditional staple food for some Sarawak communities. Fungi are widely distributed in the agricultural settings, and certain strains are known for causing infections that can affect the producers’ crops and the consumers’ health. Due to limited research conducted, the current food safety status of raw wet sago starch, remains undetermined and may pose significant risks. The aim of this research was to isolate and identify fungal species present in sago starch. The screening of fungi was conducted by using the serial dilution technique to isolate the fungi present in fifty (n=50) samples of sago starch. Identification of fungi was done by molecular analysis through species-specific PCR which targeted the ITS region. The results of all sago starch samples exceeded limit established by the Malaysian Standard for edible sago starch and complied for the International Commission for Microbiological Specification of Foods, with the highest count was 2.1 × 104 CFU/g, the lowest count was 1.3 × 102 CFU/g, and the mean count was 8.6 × 103 CFU/g. There were 45 isolated fungi derived from 10 genus, namely Aspergillus spp., Candida sp., Ceratocystic sp., Paecilomyces spp., Penicillium spp., Peniophora sp., Perenniporia sp., Phaeacremonium sp., Pleurostoma spp., and Trichoderma spp. that were detected from the samples. Based on the molecular identification, a total of eighteen (n=18) fungal species were identified, including Ceratocystic paradoxa, Trichoderma pleuroti, Trichoderma harzianum, Penicillium rolfsii, Penicillium brasilianum, Penicillium sumatraense, Penicillium verruculosum, Penicillium citrinum, Phaeoacremonium sp., Pleurostoma richardsiae, Aspergillus sydowii, Aspergillus caesiellus, Aspergillus terreus, Penicillium citrinum, Paecilomyces variotii, Paecilomyces niveus, Peniophora malaiensis, Candida blattae,and Perenniporia tephropora. In conclusion, all fifty raw wet sago starch samples collected and purchased from wet market from different districts and regions in Sarawak such as Mukah, Dalat, Matu, Pusa, Betong, Bintulu, Marudi, Miri, Sibu and Selangau were contaminated with fungi as it did exceed the permissible limits for human consumption. The outcomes from this study provided a baseline on level of fungi contamination in sago starch for future risk and mitigation assessment planning and established detailed knowledge of the food safety status in sago starch production from Sarawak, which will form a foundation for future studies
Innovation at the Intersection Exploring Technology, Sustainability and Creative Frontiers
No full textEmbark on a captivating journey through the pages of ‘Innovations at the Intersection: Exploring Technology, Sustainability, and Creative Frontiers.’ This anthology of cutting-edge research weaves a narrative of discovery, seamlessly blending the realms of technology, sustainability, and creative ingenuity. From the transformative landscapes of agarwood extraction using deep learning to the revolutionary framework for automated furniture design, each chapter unveils a unique facet of exploration.
Delve into the fusion of real and virtual worlds in immersive art practices, explore the potential of lignin-based nanoparticles in sustainable materials, and envision a future where eco-fashion principles redefine bespoke furniture design. From the ancient craft of bamboo charcoal production to the forefront of Malaysia’s energy
landscape, and ends at preserving cultural identity as a key component of cultural concepts in furniture design, this collection is a superb that transcends disciplinary boundaries.
As the pages unfold, ‘Innovations at the Intersection: Exploring Technology, Sustainability, and Creative Frontiers.’ invites readers to witness the synergy of progress, resilience, and visionary exploration. Discover the frontiers of innovation where technology meets sustainability, and creativity shapes the future. Join us on this intellectual odyssey, where each chapter contributes a vital chapter to a story of limitless possibilities and a world shaped by the convergence of diverse disciplines. Indeed, a must read collection
Hybrid Harmony Search Algorithm Integrating Differential Evolution and Lévy Flight for Engineering Optimization
Get PDFHarmony search algorithm (HSA) is extensively utilized in engineering optimization. Nevertheless,
it encounters problems of slow convergence and reduced accuracy, which hinder its capability to
escape local optima. This paper proposes HSA-DELF, a novel hybrid algorithm that combines differential
evolution (DE) and Lévy flight (LF) techniques to enhance the performance of HSA. HSA-DELF leverages
multi-mutation strategies of DE and LF random walk combined with weighted individuals to improve
exploration and exploitation based on population fitness standard deviation comparison, and adopts pairwise
iterative updates of the population to achieve faster convergence and higher solution quality. Extensive
experiments were conducted to validate performance on 23 classic benchmark functions and 12 CEC
2022 benchmark functions, followed by comprehensive testing on 7 engineering problems, demonstrating
the superiority of HSA-DELF. Comparative analysis with 5 well-known algorithms (HSA, DE, CSA, GA,
and PSO) and 4 HSA variants (IHS, MHSA, IHSDE, and IMGHSA) confirmed the robustness of HSADELF.
Statistical results, including best, mean, standard deviation, and worst values, consistently highlight
the superior performance of HSA-DELF in terms of convergence speed, solution quality, and robustness. The
Wilcoxon signed-rank test further corroborated these significant advantages. HSA-DELF showed notable
improvements in 6 out of 7 engineering problems, achieving an accuracy of 85.71%. This study establishes
HSA-DELF as an effective and reliable method for solving complex engineering optimization problems
Review on the synthesis of thiourea-triazine hybrid derivatives and its applications primarily in biological context
Get PDFThiourea and triazine are heteroatom scaolds that have been intensively employed for structural modication, particularly in the development of new drugs and the exploration of new
applications. Recent advances have initiated the concept of merging these two moieties, maximizing the potential and enhancing the properties. This review is a comprehensive compilation highlighting the various synthesis pathways of the compound comprised of both thiourea and triazine scaolds expressed in the form of fused triazinethione as well as mono-, bis-, and tristhiourea-triazine structures. The produced compounds indenitely showed the potential to be applied to various elds and industries. While this compilation majorly highlighted the biological capabilities of the thiourea–triazine compounds, a glimpse of other material chemistry applications was also included on the basis of the respective compound as documented by
precedent literature. Therefore, this review is signicant for structural modication in the eld of synthetic chemistry for intended applications
Advancing soil‑structure interaction (SSI): a comprehensive review of current practices, challenges, and future directions
Get PDFThe safety, stability, and long-term performance of reinforced concrete (RC) structures depend significantly on soilstructure interaction (SSI), a critical phenomenon governing the dynamic relationship between soil and structural behaviour. SSI plays a pivotal role in seismic design, influencing the stiffness, damping, and natural frequency of structures, yet its application in practical design remains underutilized due to challenges in modelling and integrating code provisions. This review synthesizes existing knowledge on SSI, emphasizing its impact on buildings, bridges, and foundations under static and dynamic loads. It highlights advancements in analytical, numerical, and experimental modelling methods, such as finite element analysis and discrete element methods, and evaluates their
effectiveness in capturing the complex interactions between soil and structural systems. The review identifies key gaps, including a lack of unified guidelines in international codes, inadequate integration of SSI in real-world design
processes, and limited exploration of its role in emerging engineering challenges like sustainability and climate
resilience. Historical seismic events, such as the Kobe and Loma Prieta earthquakes, are analysed to underscore the detrimental consequences of neglecting SSI considerations. Additionally, the review discusses recent innovations,
including the application of machine learning and advanced computational tools, and their potential to enhance
the accuracy and efficiency of SSI analysis. This study offers actionable insights for improving design practices, such as adapting SSI frameworks for structures on soft soils and incorporating dynamic interactions in seismic design
codes. It concludes with a call for interdisciplinary collaboration and future research into novel SSI applications, including its integration with smart sensing technologies and sustainable infrastructure design. This review bridges the gap between theoretical advancements and practical applications of soil-structure interaction (SSI) by synthesizing current knowledge, identifying critical research gaps, and proposing innovative solutions to enhance structural resilience, sustainability, and seismic safety
Driving Climate Awareness through Knowledge and Action
No full textFinal-year students from the Strategic Communication Programme, Faculty of Education, Language, and Communication (FELC), pulled off a successful roadshow as part of their PBK 4202, Strategic Campaign and Event Management course.
The Planet Pulse Roadshow was tied into the course’s main campaign, “EarthSOS: Our Planet, Our Future.” The theme was all about raising awareness of climate change and teaching the 5Rs – Refuse, Reduce, Reuse, Recycle, Rot – which are principles that help minimise waste and promote environmental responsibility, to fellow UNIMAS students. In addition, it showed how learning can be fun with play activities