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Dragon fruit, also called pitaya or pitahaya, is in the family Cactaceae. It is found in two genera: 'Selenicereus' and 'Hylocereus'. The substantial growth in demand intensifies dragon fruit processing operations, and waste materials such as peels and seeds are generated in more significant quantities. The transformation of waste materials into value-added components needs greater focus since managing food waste is an important environmental concern. Two well-known varieties of dragon fruit are pitaya (Stenocereus) and pitahaya (Hylocereus), which are different in their sour and sweet tastes. The flesh of the dragon fruit constitutes about two-thirds (~65%) of the fruit, and the peel is approximately one-third (~22%). Dragon fruit peel is believed to be rich in pectin and dietary fibre. In this regard, extracting pectin from dragon fruit peel can be an innovative technology that minimises waste disposal and adds value to the peel. Dragon fruit are currently used in several applications, such as bioplastics, natural dyes and cosmetics. Further research is recommended for diverging its development in various areas and maturing the innovation of its usage. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae is a gram-negative bacterium that causes serious illnesses, including pneumonia, liver abscess, meningitis, bloodstream infections, and urinary tract infections (UTIs). This study aimed to isolate and diagnose K. pneumoniae from clinical specimens of urine from patients with UTIs and perform molecular detection of the blaSHV-la gene in K. pneumonia in the Najaf Province, Iraq. The study included 100 clinical specimens from October 2021 to March 2022. As an initial diagnosis, K. pneumoniae isolates were diagnosed based on culture and biochemical features. Apart from the usage of polymerase chain reaction (PCR) technology to identify the blaSHV-la gene, the final diagnostic was achieved by the automated Vitek-2 compact system. The biochemical findings revealed that 40 out of every 100 isolates tested positive for K. pneumoniae. These results were validated by Vitek, which revealed that 40/100 of the samples tested positive for K. pneumoniae, and by PCR utilizing the blaSHV-la gene, which showed that 13/40 of the samples tested positive for K. pneumoniae isolated from the urine of patients with UTIs. In conclusion, the results indicated that the use of the Vitek-2 technique was required to confirm the accurate identification of the pathogen. Klebsiella pneumoniae clinical isolates showed multidrug resistance to antibiotics commonly used to treat UTIs. The blaSHV gene encoded for Extended-spectrum beta-lactam antibiotic was found almost in K. pneumoniae isolates. [ABSTRACT FROM AUTHOR]

It is essential to understand the factors influencing thermal responses to improve human comfort and properly reduce energy consumption. It has been confirmed that parameters unrelated to the thermal environment can influence the thermal responses of occupants. These factors are yet to be investigated and studied in detailed, especially under different environmental conditions because of insufficient knowledge about indoor environment factor interactions. Therefore, accurate and high-quality data of light intensity is highly important to be focused on. Accordingly, the influences of light intensity on the temperature and air velocity of the indoor environment were studied and investigated under natural and controlled environmental conditions. The main objectives are to investigate and evaluate various effects of light intensity parameters on the indoor room temperature and air velocity for the indoor environmental condition. An effect of light intensity and simulation analysis for the indoor environment was performed using the ANSYS platform. The main parameters such as indoor temperature and air velocity were measured. Based on the results obtained from simulation analysis, the halogen lamps possess an enormous influence on the indoor environmental parameters than the LED lamps; the light intensity is directly proportional to the air velocity and indoor temperature. Conclusively, the results of this study can be considered as a reinforcement step in emphasizing the actual effect of lighting intensity, and the required lighting must be in accordance with the daily duty. [ABSTRACT FROM AUTHOR]

Membrane distillation (MD) is a promising water desalination technology that is capable of treating high salinity water. However, the problematic fouling issues and membrane wetting are the primary impediments to the large-scale application of this technology. To overcome the mentioned problems, the distilling membrane should be made from anti-wetting materials and possess a highly porous structure. In this study, a superhydrophobic nanofibrous membrane was fabricated through surface coating of electrospun polyacrylonitrile (PAN) nanofibres membranes using silica nanoparticles and fluorinated alkyl silane surface treatment. The coated PAN nanofibre membranes were characterised using scanning electron microscope (SEM), water contact angle (WCA) method, Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC). It was observed that the amount and size of silica nanoparticle were related to hydrolysis time, which was crucial in determining the membrane pore size and formation of superhydrophobic surface. The presence of silica nanoparticles and fluorine content significantly improved the hydrophobicity and thermal properties of the nanofibres. The results from this study provide valuable insights into the understanding of the behaviour of silica nanoparticles and the method to fabricate superhydrophobic electrospun nanofibre membranes for MD application. [ABSTRACT FROM AUTHOR]

This paper presents a study on the implementation of dark and raining environment test conditions to investigate Lane Support System (LSS) performance for passenger cars in Southeast Asia. The case study has been performed for Malaysian domestic roads. LSS systems involved have been the Lane Departure Warning (LDW) and Lane Keep Assist (LKA). The literature review conducted has revealed that there is not yet a similar study performed for vehicle LSS system. The motivation of this study has been to identify the effect of both environmental conditions on the vehicle LSS performance. This pioneering work is also aimed to help in establishing a new LSS test protocol that could reflect better the driving situations in Southeast Asia countries. The experimental works have been carried out at state road in Melaka, Malaysia. LSS on-road test parameters have been adopted from LSS test protocols from the European New Car Assessment Programme (Euro NCAP) and the Japan National Agency for Automotive Safety and Victim's Aid (NASVA). A new test procedure to carry out the study has been also developed in this study in order to complement the referred test protocols, including customized rain-making testing equipment to simulate the raining environment conditions. Results from the study have showed that both LDW and LKA systems performance could successfully be evaluated when subjected to dark and raining environment conditions using the new test procedure. Furthermore, the new test procedure developed in this study is also highly applicable for implementation in future LSS on-road tests involving any type of road category (both domestic and highway) with minimal setting up process. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present research findings on the measurements of mechanical, morphological, and thermal properties of Roselle fiber-reinforced thermoplastic polyurethane composites. The Roselle fiber/thermoplastic polyurethane composites were prepared with fibers of different sizes such as 125 µm and lower, 125–300 and 300–425 µm by internal mixer and hot press at 170°C. The results show that mechanical properties (tensile, flexural, and impact properties) of the composites were improved with the increase in fiber sizes. The highest tensile (10.45 MPa), flexural strength (6.93 MPa), and impact strength (20.22 kJ/m2) was obtained from composites with 300–425 µm fiber size of Roselle fiber/thermoplastic polyurethane composites. Morphological properties of dispersion fiber and tensile fracture surfaces were studied using scanning electron microscope. Thermal properties of the composites were studied using thermogravimetric analyses and results showed that the thermal decomposition effect was almost similar for all compositions. [ABSTRACT FROM PUBLISHER]

This paper presents the perforation behaviour of polyethylene terephthalate (PET) foam cored sandwich structures when subjected to quasi-static and dynamic loading at normal (0°) and oblique angles of 10° and 20°. An instrumented drop-weight hammer rig was used with fully-clamped conditions for the low-velocity impact test with impact energy of 40 J and velocity of 3.78 m/s. Meanwhile, the quasi-static indentation test was carried out using a universal testing machine via an Instron 4505, at crosshead displacement rate of 1 mm/min, with boundary conditions similar to those of the dynamic test. Results obtained showed that the normal impact generated the highest peak force for both the first and second peaks, which are associated with the damage to the top and bottom skins of the sandwich structures. Moreover, regardless of whether the test was done on the normal or inclined angles, it was observed that the dynamic loading produced higher force magnitude in comparison to those of the quasi-static response, due to the enhanced strength and stiffness of the components because of the strain rate and inertia effects. However, in terms of the damage profiles, it is evident that the maximum damage area increased with the increase inclination angle as supported by simple geometric analysis. For the oblique impact cases, the damage was due to the combined effect of tensile, compression and shear for impact at 10°. The damage occurred as a result of pure shearing for the 20° impact case. In conclusion, the perforation behaviour at inclined angles allowed more area to be perforated in comparison to those of the normal cases. [ABSTRACT FROM AUTHOR]

The fossil fuel price crisis and emissions control in the transportation sector in Malaysia have become national issues, especially in the transportation sector. As an alternative, using hydrogen mixed with gasoline fuel in conventional combustion engines is a very effective way of improving engine performance and emission control. Generating hydrogen via a chemical reaction between hydrochloric acid and aluminium is a new approach in this study. This methodology has been tested through the mixture application (G + H2) in 10-year-old motorcycles (gasoline) with a modified conventional carburettor engine. The testing of engine performance by chassis dynamometer was done at three levels of experiments: L0: 0 Amp load, L1: 1 Amp load, and L2: 2 Amp load for different engine performances, particularly in identifying quality improvements through the brake thermal efficiency. The study found that the average increase in brake thermal efficiency was 23% higher in the (G + H2) engine compared to gasoline only. The results of this study have proven that the use of hydrogen (Al + HCl) in the stoichiometric ratio has helped to increase combustion efficiency, especially when the oxygen content in the fuel mixture ratio is not adequate during the stroke of power. The successful reduction in fuel consumption, increased engine performance, reduction of pollution and the system's ability to meet the basic needs of the internal combustion engine cycle can be beneficial to the development of the automotive industry, particularly in the transport sector. [ABSTRACT FROM AUTHOR]

Under the double-degree programme offered by Universiti Kebangsaan Malaysia (UKM), a number of Universitat Duisburg-Essen (UDE) students are required to study in UKM for one semester each year. They are free to choose any courses offered in the programme for that particular semester. In Semester 1 of the 2014/2015 session, the Department of Mechanical and Materials Engineering ran four courses that were enrolled in by students from both universities. Given the different background, ways of thinking and academic competencies, it was expected that the students would perform differently and it was predicted that the German students would demonstrate better achievement compared to UKM's mostly Malaysian students. The objective of this study was to discover if there was a difference in terms of performance between the international students and the host students who took the same courses. This paper consists of three main sections. First, after a general introduction of the study, the methodology is explained. Second, a comparison of examination-based achievement in four selected courses between the two groups of students is presented in summary. Finally, some possible reasons as well as explanations for the difference or similarity in the performance of the two groups is considered. The findings suggest that in general, students from UDE showed better performance than the host students. In the long term, this study is intended to be useful in improving the quality of teaching and learning in UKM, specifically when dealing with students from UDE as well as home students. [ABSTRACT FROM AUTHOR]

In this report, rules of mixture (ROM) and rule of hybrid mixtures (RoHM) were utilized to predict the mechanical properties of kenaf/glass fiber reinforced polypropylene short random oriented hybrid composites material. Three hybrid composition were studied with total fiber contents 30 vol%, 40 vol% and 50 vol% and the relative glass fiber contents are varied from 0 to 100 vol%. Analytical results using the both micromechanical models show that the hybridization between kenaf with glass fiber in short fiber form using polypropylene matrix give positive hybrid effect to the overall hybrid stiffness at minimum relative glass fiber volume fraction of 87.5% compared to the kenaf/polypropylene composites single system for all total fiber volume content cases. Similarly, it was also observed that the stiffness of the hybrid short and randomly oriented composites increases as the overall fiber volume contents increases. The overall results have provided useful insight of the hybridization effects to the stiffness of the final hybrid composites especially for the application in product development process using similar hybrid short randomly oriented kenaf/glass fiber reinforced polypropylene composite materials. [ABSTRACT FROM AUTHOR]