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Quick understanding of clay-sand stabilization in strength performance assessment on CBR and UCT tests
No full textThe clay contain is fine-grain fractions with low bearing capacity. The clay can be improved by adding sand as coarse-grains. Incorporate the sand in clay mixture does not always exhibit the same trend of increasing in strength from different mechanical tests. This study aims to quickly understand the effective sand content in clay soil by UCT and CBR tests. Clay mixed with two sand contents of 10% and 20%. The samples are cured for four days before testing. According to the USCS method, the clay has a high plasticity
index (CH). Meanwhile, sand is classified in the sand group with a small number of fine-grains. Clay-sand stabilized obtained an increase in strength with a positive trend using the CBR test but has a negative trend when using UCT. The unconfined compressive strength decreases at an additional 20% sand content. Presence the coarse fraction and decrease in cohesiveness of clay, as well as unconfined samples condition lead a decrease in compressive strength. Therefore, it can be emphasized that UCT is only suitable for clay or cohesive soils with effective sand content of 15% maximum
Why Do Tourists Buy Culture? An Investigation of Demographic Differences in Cultural Souvenir Preferences among Chinese Tourists
No full textThis study investigates how demographic factors shape Chinese tourists’ preferences for cultural souvenir design and influence their purchase intentions. Despite the significance of souvenir consumption in tourism, the role of consumer demographics remainsunderexplored, especially in the Chinese outbound market. Drawing on the Theory of Planned Behavior and semiotics, this research examines how gender, age, income, and education affect evaluations of three design attributes—aesthetic value, care & travel convenience, and uniqueness—and their moderating role in shaping purchase intention. Based on survey data from 620 domestic Chinese tourists, structural equation modeling and hierarchical regression reveal that all four demographic factors not only influence design preferences but also significantly moderate their effect on purchase intention. For example, women are more sensitive to symbolic aesthetics, older and higher-income tourists respond more strongly to design features, and higher education enhances design influence. The study extends consumer behavior theory by establishing demographics as key moderators and offers practical implications for segmented marketing and design strategies in cultural tourism.
Keywords: Cultural Souvenirs; Design Preferences; Purchase Intention; Demographic Moderators; Chinese Tourist
Coolant Characterization and Predictive Monitoring System for Heavy-Duty Trucks using Machine Learning
No full textOver 50% of engine failures are attributed to poor coolant system maintenance. This study reports on a fleet test of automobile coolants and the development of a monitoring system to evaluate coolant performance. The fleet test was conducted on six trucks, where parameters such as pH, reserve alkalinity (RA), ethylene glycol (EG) content, and functional characteristics of the coolant were measured over eight months, and then subjected to regression learning. A
coolant monitoring system was also developed to record and visualize coolant performance. The tensile strength of the radiator hose was examined to assess the impact of coolant on hose integrity. The study identifies pH as the most suitable indicator of coolant health against mileage
with its stable degradation trend and clear threshold, though insensitive to coolant dilution. The C-O vibration of EG, as detected by Fourier Transform Infrared (FTIR) analysis, corresponded well with EG content determined using a refractometer. There was no evidence that coolant
affects the tensile strength of the radiator hose. The Gaussian Process Regression (GPR) model was used to predict coolant degradation and estimates the optimal replacement mileage at of 111,473.65 km. This study introduces a data-driven coolant management approach to enhance reliability, cut maintenance costs, and reduce downtime
PHYTOCHEMICAL ANALYSIS OF COFFEE BY-PRODUCTS: SARAWAK LIBERICA COFFEE SILVERSKIN AND COFFEE LEAVES
No full textCoffee Silverskin (CS) and the leaves are by-products generated during the harvesting of green coffee beans. CS and the leaves obtained from the major Liberica
species cultivated in Sarawak, Malaysia, remain underexplored. This study investigated the bioactive compound composition of Sarawak Liberica coffee silverskin and leaf extracts using gas chromatography coupled with mass spectrometry (GC-MS). Phytochemical analysis was conducted on the extracts of both CS and leaves. The GC-MS analysis
revealed the presence of 41 chemical compounds, with four major compounds identified:5-hydroxymethylfurfural (5-HMF), D-allose, 1,6-anhydro-β-D-glucofuranose, and caffeine in the CS extract. The results indicated that the percentage of caffeine content in the CS extracts showed no significant difference (p < 0.05) between ethanol (1.55± 0.47%), methanol (1.77 ± 0.38%), and water (1.92 ± 0.65%). Additionally, the total phenolic content (TPC) of Liberica coffee leaves was measured at 35.76 ± 2.12 mg GAE/g
extract, while the total flavonoid content (TFC) was 605.85 ± 8.20 mg QE/g extract. The antioxidant activity of Liberica coffee leaves was recorded at 54.37 ± 0.10%. The
substantial presence of bioactive compounds suggests potential applications in food and pharmaceutical formulations
The environmental Kuznets curve in Japan with nuclear energy and foreign direct investment using ARDL and NARDL models
No full textThis study investigates the relationship between carbon dioxide (CO2) emissions, economic growth, nuclear energy, and foreign direct investment (FDI) in Japan over the period 1985–2023. Employing autoregressive distributed lag (ARDL)
and nonlinear ARDL (NARDL) models, it tests the Environmental Kuznets Curve (EKC) hypothesis and explores both linear and asymmetric dynamics. The results confirm the EKC pattern, showing that economic growth initially raises emissions but reduces them beyond a critical income threshold. Nuclear energy is found to significantly lower CO2 emissions, underscoring its role as a low-carbon energy source, although transitional adjustment costs are observed in the short run. By contrast, FDI exerts a small but positive influence on emissions, suggesting that capital inflows may contribute to environmental pressures in the absence of strict regulatory oversight. These findings highlight the importance of stable nuclear energy policies, enhanced green investment screening, and integrated energy strategies for achieving Japan’s carbon neutrality targets. This research contributes new evidence by jointly analysing GDP, nuclear energy, and FDI within the EKC framework and by applying asymmetric methods to capture Japan’s post-Fukushima energy transition
Gut microbiome community profiling of Bornean bats with different feeding guilds
Get PDFBats are extraordinary mammals. They have evolved to consume various dietary sources, such as insects, fruits, nectar, blood, and meat. This diversity has generated considerable interest in the scientific community, resulting in efforts to leverage bats as model organisms to study the correlation between diet and gut microbiome community. Although such studies now commonly use Next Generation Sequencing (NGS), similar studies are early in their development in Southeast Asia, especially in Malaysia, which harbours an incredibly diverse bat fauna. This study provides pioneering NGS metabarcoding information on Bornean bats. By using a high-throughput Nanopore-based 16S rRNA gene sequencing method, Bacillota, Pseudomonadota, and Campylobacterota were found in insectivorous bats and phytophagous bats. Both
nsectivorous and phytophagous groups harboured
no dominant taxon (D=0.076; D=0.085). A comparative analysis of gut bacteria functional groups identified
eight major groups in both phytophagous and insectivorous bats, with fermentation being the predominant group. The correlation network analysis revealed a negative correlation between the ‘good bacteria’ Lactobacillus and various pathogenic bacteria genera, such as Salmonella (-0.4124) and Yersinia (-0.4654), demonstrating its prebiotic characteristics. This study broadens our understanding of the bat gut microbiome from various diets, with emphasis on new data from Borne
Model Predictive Controller (MPC) Design for an UAV Quadcopter in Windy Critical Environment
Get PDFUnmanned Aerial Vehicles (UAVs), particularly quadcopters, have become indispensable in navigating critical windy environments, offering unparalleled access to complex terrains. These challenging environments pose unique navigational difficulties due to fluctuating wind patterns, which significantly impact UAV performance and accuracy. This research enhances UAV navigation effectiveness and stability through the development of a robust controller—specifically, a cascade Model Predictive Control (MPC) algorithm, optimized for continuous gust conditions as modelled by the Dryden wind turbulence approach. To accurately capture UAV dynamics within these environments, a mathematical model was developed using the Newton-Euler technique. This approach enabled precise analysis of both translational and rotational motions, factoring in elements such as inertia, torque, and external forces like drag and lift. The cascade MPC was further validated through real-time experiments, adapting UAV dynamics to unpredictable turbulence patterns and obstructions. This system’s adaptability and precision are contrasted with a Proportional-Integral-Derivative (PID) controller, highlighting MPC's predictive advantages for dynamic environments. Experiments were conducted in mangrove forests, settings characterized by complex wind patterns, using a UAV equipped with a Pixhawk hardware controller. The UAV followed predefined paths to collect data on altitude, roll, pitch, yaw, and responses to wind turbulence, enabling refined control strategies and model improvements based on real-world performance. Comparative analysis shows that the quadcopter, when equipped with MPC, not only achieved better stability and responsiveness but also improved operational efficiency under adverse weather conditions, demonstrating the system’s robustness and applicability to challenging UAV operations. This research thus advances UAV deployment in demanding real-world applications by integrating sophisticated dynamic modelling with innovative control techniques
Optimization of Chitosan-Alginate Hydrogel Properties for Controlled Release of Urea
Get PDFThis study explored the effects of synthesis parameters such as chitosan molecular weight, alginate loading, and crosslinker loading in optimizing chitosan-alginate hydrogel using response surface methodology prepared by ionotropic gelation. Box-Behnken design evaluated the effects of chitosan molecular weight, alginate loading (2.5
to 4.5 wt%), and crosslinker loading (0.10 M to 1.00 M) on encapsulation efficiency, swelling behaviour and urea release. The hydrogels were spherical and with a mean diameter of 3.82 ± 0.78 μm. FTIR analysis confirmed the interactions between chitosan, alginate and crosslinker
added. Encapsulation efficiency was maximized at 89.43 ± 12.66%, with alginate concentration (3.5 wt%) being the most significant factor (p = 0.001264). Higher alginate concentrations improved encapsulation by facilitating crosslinking with Ca²⁺ ions. Swelling studies revealed an
average swelling capacity of 33.27 ± 17.26%, peaking at 77%. Urea release over 2 hours averaged 20.08 ± 16.39%, with minimal release observed in formulations using lower molecular weight chitosan and moderate alginate concentrations (p = 0.01535). Statistical models indicated high adequacy for encapsulation efficiency (R² = 0.844) but limited predictive power for swelling (R² = 0.4987). The findings demonstrated the influence of formulation variables on hydrogel properties, underscoring their potential as nutrient delivery systems with controlled release and
swelling behaviour
Narrative Review of Cervical Cancer in Malaysia: Knowledge and Challenge
Get PDFAccording to the 2019 Malaysia National Cancer Registry Report (MNCR), 3,981 cases of cervix uteri cancer were diagnosed between 2012 and 2016, compared to 4,352 cases in
the 2007-2011 report. The third most common cancer in women was cervix uteri cancer, ranked ninth in Malaysia, up from seventh in the previous survey. Over the last five years, the incidence rate has dropped from 7.6 to 6.2 per 100,000 people. Cervical cancer is the most prevalent disease among women. The Pap smear is the main technique for identifying potentially cancerous cells. The purpose of this research paper is to investigate women's knowledge and understanding of cervical cancer in Malaysia, attitudes toward cervical cancer (CC) among Malaysian women, and the challenges faced
by medical professionals. The primary articles came from the two established databases, which are SCOPUS and Web of Science (WoS). The advanced searching focuses on two
keywords: cervical cancer and Malaysia. Based on previous research, the study involves an overview of women's awareness and knowledge, a cross-sectional study, a selfsampling
device, and perceived barriers to having a pap smear test in Malaysia. Furthermore, it was discovered that ethnicity promotes HPV vaccines, and MSPs may be given for medical students' programs aimed at preventing the spread of cervical cancer, as well as vaccination subsidies. Providers and academia should co-operate to raise immunization coverage. The majority of women surveyed in Malaysia are women
between the ages of 21 and 60. In contrast to other research, there is still a shortage of understanding about cervical cancer, which has resulted in implicit cluelessness and
negative perceptions toward it. Regarding the risk aspects, there are two well-known among Malaysian women: unprotected sexual partners and sexually transmitted infections. Participants are aware that a normal Papanicolaou (Pap) smear would detect cervical cancer and that an operation may be an option. Besides that, people in Malaysia have a modest understanding of Pap smears as a preventative measure to diagnose and prevent Cervical Cancer at a preliminary phase. In summary, most women in Malaysia understand the importance of the Pap test screening technique for early detection and
operation as a cure. More initiative will be needed with the potential to increase understanding of women's perceptions to-wards cervical cancer