The prediction of wake wash in the towing tank

The wash or ship-generated waves from high speed craft has become a common subject in research and development of marine transportation. Since some time now the wake wash of high speed craft has become a problem in particular on inland or confined waterways. This wake wash has an impact on safety and environment such as bank/shoreline erosion, risk to people on shore and small boats in harbors and changes in the local ecology. This paper describes the results of model test of a high speed patrol, together with theoretical prediction of wake wash

Kualiti pengalaman pembelajaran pelajar-pelajar sarjana muda kejuruteraan elektrik di Kolej Universiti Teknologi Tun Hussein Onn (KUiTTHO) dari aspek pembelajaran kognitif, psikomotor dan afektif

Pembelajaran kognitif, psikomotor dan afektif merupakan pembelajaran yang perlu ditekankan dalam konteks pengajaran dan pembelajaran di institusiinstitusi pengajian tinggi. Ketiga-tiga aspek pembelajaran tersebut amat penting bagi melahirkan graduan yang mempunyai ketrampilan yang tinggi dari segi kreativiti, berinovatif, berkaliber, berkompetensi serta mempunyai motivasi kendiri yang tinggi. Kajian ini adalah satu kajian untuk menilai kualiti pengalaman pembelajaran pelajar-pelajar Saijana Muda Kejuruteraan Elektrik di KUiTTHO. Kajian ini meninjau pengalaman pembelajaran di dalam kelas dan di makmal/bengkel dari aspek pembelajaran kognitif, psikomotor dan afektif. Responden terdiri daripada empat puluh orang pelajar Saijana Muda Kejuruteraan Elektrik semester akhir yang dipilih secara rawak. Instrumen yang digunakan dalam kajian ini ialah jenis soal selidik di mana penilaian dilakukan berdasarkan persepsi responden terhadap pengalaman pembelajaran yang ditempuhi sepanjang pengajiannya serta menjalankan sesi temubual dengan beberapa orang responden. Data-data yang dikumpulkan, dianalisis menggunakan SPSS version 11.0 yang melibatkan skor min dan sisihan piawai. Dapatan kajian menunjukkan kualiti keseluruhan pengalaman pembelajaran pelajar adalah di tahap sederhana (skor min = 3.49). Bagi pengalaman pembelajaran di dalam kelas dan makmal, kualitinya adalah di tahap sederhana (skor min = 3.31 dan 3.67 masing-masing). Sementara kualiti keseluruhan pengalaman pembelajaran dari aspek kognitif, psikomotor dan afektif juga berada di tahap sederhana (skor min = 3.50, 3.39 dan 3.57 masing-masing). Oleh itu, berdasarkan kualiti pengalaman pembelajaran pelajar yang sederhana ini, pengkaji telah membina satu produk cadangan iaitu Sistem Senarai Semak Kualiti Pengajaran dan Pembelajaran bagi membantu pihak pengurusan akademik KUiTTHO meningkatkan kualiti pengajaran dan pembelajaran dari ketiga-tiga aspek kognitif, psikomotor dan afektif

Computer self-efficacy, anxiety and attitudes towards use of technology among university academicians: a case study of University of Port Harcourt Nigeria

The 21st century also called ICT literacy includes not only the traditional concept of literacy, but it also encompasses the ability to incorporate new technologies into teaching and learning. The paper focus on computer, self-efficacy, anxiety and attitudes towards use of technology, as it influence the behavioral intention of the university academicians to accept and use ICT for teaching and learning. The University of Port Harcourt Nigeria was use as a case study, and 100 questionnaires were administered and collected. The technology usage by the academic staff shows that 74% are willing to use ICT once or more a day. 51% of the respondents said that the use of ICT is voluntary. Three null hypotheses were stated. The findings shows that the Uniport academic staff had medium computer anxiousness, they have moderate computer self efficacy and high attitudes towards use of technology. Therefore, as attitudes towards use of technology increase, computer self efficacy also increase and this cause a gradual decrease in computer anxiety. The most influential construct is attitudes towards use of technology. This was determined by the regression analysis and the hypotheses. The knowledge gained from this study is beneficial to university administrators, academic staff and the Nigerian ICT policy makers

Coherence in amalgamated algebra along an ideal

Let $f: A\rightarrow B$ be a ring homomorphism and let $J$ be an ideal of $B$. In this paper, we investigate the transfert of the property of coherence to the amalgamation $A\bowtie^{f}J$. We provide necessary and sufficient conditions for $A\bowtie^{f}J$ to be a coherent ring

Experimental evaluation of physicochemical properties and tapping torque of hexagonal boron nitride in modified jatropha oils-based as sustainable metalworking fluids

In consideration of the important role of environmentally begin metalworking fluid (MWF) in the machining industry, jatropha oil has been acknowledged as a suitable type of lubrication based oil. Despite its advantages, crude jatropha oil (CJO) had its main drawback in terms of poor thermaloxidative stability due to the presence of unsaturated molecules that leads to oxidation reaction. The objective of this study was to evaluate the physicochemical properties and tapping torque of newly developed modified jatropha oils (MJOs). Initially, CJO was chemically modified through the transesterification process at various molar ratios of jatropha methyl ester (JME) to trimethylolpropane (TMP) to produce a series of MJOs denoted as MJO1, MJO3, and MJO5. Hexagonal boron nitride particles at concentrations of 0.05, 0.1 and 0.5 wt% were mixed with the MJOs. MJOs with and without hBN particles were analysed based on the physicochemical testing (i.e., acid value, viscosity, viscosity index (VI) and flash point) and tapping torque test (i.e., tapping torque, thrust force and tapping torque efficiency). Experimental results showed an improvement of physicochemical properties of these newly developed MWFs with the increase in JME:TMP molar ratio and concentration of hBN particles. MJO5 displayed the best physicochemical properties with the highest VI of 196, compared with MJO3 and MJO1. The addition of 0.5 wt% of hBN particles in MJO5 (MJO5c) caused the highest VI achieved at 228, compared with the other samples. The average tapping torque and thrust force were reduced approximately by 15% and 45%, respectively using MJO5a (0.05 wt% of hBN particles with MJO5), compared with SE. MJO5a also demonstrated an improvement of 118% tapping torque efficiency that indicated an excellent machining performance. In conclusion, MJOs containing hBN particles showed better performances on the lubricating property. Among the samples, MJO5a could be proposed to substitute synthetic ester as a sustainable MWF for machining processe

Performance of modified jatropha oil in combination with hexagonal boron nitride particles as a bio-based lubricant for green machining

This study evaluates the machining performance of newly developed modified jatropha oils (MJO1, MJO3 and MJO5), both with and without hexagonal boron nitride (hBN) particles (ranging between 0.05 and 0.5 wt%) during turning of AISI 1045 using minimum quantity lubrication (MQL). The experimental results indicated that, viscosity improved with the increase in MJOs molar ratio and hBN concentration. Excellent tribological behaviours is found to correlated with a better machining performance were achieved by MJO5a with 0.05 wt%. The MJO5a sample showed the lowest values of cutting force, cutting temperature and surface roughness, with a prolonged tool life and less tool wear, qualifying itself to be a potential alternative to the synthetic ester, with regard to the environmental concern