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Understanding the Perception of Islamic Medicine Among the Malaysian Muslim Community
No full textThis study was conducted to identify and describe the patients’ perceptions of Islamic medicine based on gender, age, marital, educational level and working status among the Malaysian Muslim population. A nationwide interviewer-administered questionnaire survey was conducted in 2013. An open-ended questionnaire pertaining to Islamic medicine was used to increase the probability of capturing maximum data. This survey implemented a multistage design, stratified by state, proportionate to the size of the state population and was representative of the Malaysian population. Post-survey classification of results was performed accordingly. Complex data analysis was carried out using SPSS 16.0. The discussion was identified and categorised into various sections. The paper concludes that Islamic medicine has a major influence in the Malaysian Muslim community compared to other alternatives. Further, its potential for growth and importance especially for treating spiritual ailments cannot be denied. The respondents indicated that two factors motivate Islamic medicine in Malaysia: (1) the Muslim community opts for alternative healing because of their dissatisfaction with conventional methods; (2) Islamic medicine focuses only on healing spiritual-related problems. The average perception of respondents is that the function of Islamic medicine in healing physical diseases is undervalued and that it is not suitable to replace the functions of modern health institutions
Supercontinuum Micrometer-Displacement Sensor Using Single-Multi-Air-Gap-Single Mode Fiber as Sensing Probe
No full textIn this paper, a displacement sensor utilizing a Mach-Zehnder interferometer with a single-multi-air-gap-single mode (SMAS) fiber structure is proposed and demonstrated. A 30-cm-long four-mode step index fiber (FMSIF) is used as the multimode fiber in the SMAS structure, with the left end of the FMSIF fusion spliced to a 50-cm-long single-mode fiber (SMF-28). The right end of the FMSIF is aligned to another 50-cm SMF-28 on the v-groove of Fitel S178A fusion splicer but without splicing, creating an air gap with a tunable length of 0-300μm. The performance of the displacement sensor is investigated over the range of 1.1-1.7μm using a supercontinuum source. Through the experiment wavelength range, the highest sensor sensitivity is achieved at 1.7 μm with a sensitivity of 12.3 pm/ μm and an R2 coefficient of 0.926. The implementation of a displacement sensor utilizing the simple and cost-effective concept of the SMAS will be beneficial for use in various areas, such as biomedicine, manufacturing, and engineering
Multi-wavelength Praseodymium fiber laser using stimulated Brillouin scattering
No full textA multi-wavelength Brillouin Praseodymium fiber laser (MWBPFL) operating at 1300 nm region is demonstrated based on the hybrid scheme by utilizing Brillouin gain medium and Praseodymium-doped fluoride fiber as linear gain medium. A 15 µm air gap is incorporated into the cavity to allow the switching of Brillouin frequency spacing from double to single spacing. Under the Brillouin pump of 8 dBm and the 1020 nm pump power of 567.2 mW, 36 Stokes lines with a wavelength spacing of 0.16 nm and 24 Stokes lines with a wavelength spacing of 0.08 nm are achieved. The wavelength tunability of 8 nm is realized for both MWBPFLs by shifting the Brillouin pump wavelength. The MWBPFLs exhibit an excellent stability in the number of generated Stokes and power level over one-hour period
Nickel oxide nanoparticles grafted with Chitosan as saturable absorber for tunable passively Q-switched fiber laser in S+/S band
No full textA tunable, passively Q-switched fiber laser using nickel oxide nanoparticles grafted onto a chitosan host (NiO/Chitosan) as saturable absorber (SA) is proposed and demonstrated for operation in the S+/S band region. The generated Q-switched pulses can be tuned from 1452 nm to 1515 nm, giving a tuning range of 63 nm. The pulses have a repetition rate from 12.3 kHz to 30.8 kHz as well as minimum pulse width and maximum pulse energy of 3.5 µs and 61.0 nJ, respectively at maximum pump power of 135.8 mW. To the best of the author's knowledge, this is the first time that tunable Q-switching operation in the S+/S band region is obtained using a NiO/Chitosan based SA
Wide-band, passively Q-switched Yb- and Tm-doped fibre laser using WSSe saturable absorber
No full textA wide-band, passively Q-switched fibre lasers based on ytterbium- and thulium-doped fibre gain medium are proposed and demonstrated. The lasers employ a transition metal dichalcogenide, tungsten sulphoselenide as a saturable absorber (SA) which is prepared by mechanical exfoliation technique. By integrating the SA in the laser cavities, self-starting Q-switched at 1038 and 1982 nm are obtained. The generated pulses exhibit a microsecond pulse duration with few kilohertz repetition rate. The proposed SA has high potential as a new material to cater to the needs of various scientific, industrial and biomedical applications
Generation of an ultrabroadband supercontinuum in the mid-infrared region using dispersion-engineered GeAsSe photonic crystal fiber
No full textAn ultrabroadband mid-infrared (MIR) region supercontinuum (SC) is demonstrated numerically through dispersion-engineered traditional chalcogenide (ChG) photonic crystal fiber (PCF). By varying structural parameters pitch (hole to hole spacing) and air-hole diameter to pitch ratio, a number of 10-mm-long hexagonal PCFs made employing GeAsSe ChG glass as a core and air-holes of hexagonal lattice running through their lengths as a cladding are optimized to predict an efficient mid-infrared region SC spectral emission by pumping them using a tunable pump source between 2.9 and 3.3 µm. Simulations are carried out using an ultrashort pump pulse of 100-fs duration with a low pulse peak powers of between 3 and 4 kW into the optimized designs. It is found through numerical analysis that efficient SC spectral broadening with flattened output can be obtained by increasing the PCF pitch rather than increasing the PCF cladding containing air-hole diameter although a larger nonlinear coefficient could be obtained through increasing air-hole diameter of an optimized design. Simulation results show that the SC spectra can be broadened up to 12.2 µm for a certain design with a peak power of 3 kW. Using a peak power of 4 kW, it is possible to obtain SC spectral broadening beyond 14 µm with an optimized design spanning the wavelength range from 1.8 to 14 µm which covers the electromagnetic spectrum required for MIR molecular fingerprint region applications such as sensing and biological imaging
Enhancement of broadband ultraviolet visible photodetection by boron nitride nanoparticles in bulk graphene oxide layer
No full textA proposed boron nitride/graphene oxide (BN/GO) composite photodetector (PD) was prepared using a drop cast method for photodetection in the ultraviolet (UV) and visible light ranges. Morphology of the GO, distribution of BN nanoparticles and composition of B, N, C and O elements were confirmed by field emission scanning electron microscope (FESEM) analysis and energy dispersive x-ray (EDX) spectroscopy results. Raman scattering indicates high frequency intrinsic E2g vibrations at 1349 cm−1 and low intense peaks at 803 cm−1 from hexagonal BN (h-BN) structures in the bulk GO layer, while an overlap in the D and G bands at 1349 and 1581 cm−1 respectively indicates the presence of the GO layer. Excellent photoconduction of 380 and 405 nm UV sources and a 650 nm red laser source showed that the measured photocurrent is dependent on power regardless of the signal wavelength. Variations in sensitivity allow the device to be operated at selected direct current (DC) bias voltages, while high frequency modulation at 1000 Hz showed a profound rise and fall time about 13.6 and 245.6 μs respectively. Characteristics as self-powered PD was observed, has an enhancement about 3450% at its zero bias voltage
Loss and recovery of carbon and nitrogen after mangrove clearing
No full textOffsetting carbon (C) emissions and reducing nitrogen (N) pollution have been goals of mangrove restoration programs around the world. There is a common, yet dubious expectation that mangrove restoration will result in immediate and perpetual delivery of ecosystem services. There are expected time lags between mangrove clearing and C and N losses, and between restoration and C and N gains. Obtaining accurate rates of losses and gains requires frequent and long-term sampling, which is expensive and time consuming. To address this knowledge gap, we used a chronosequence of mangrove forests in mangroves in Matang Mangrove Forest Reserve (MMFR) in Malaysia, a region with one of the most C dense forests in the world. In this site, we assessed the ecosystem C and N stocks, including soil, downed wood, downed litter, and trees. The objective was to measure C and N changes through time. After mangrove clearing, C and N losses in soil and downed wood were rapid, with stocks halved after just one year. In the first 10 years after replantation, the forest recovered quickly, with rates of C accumulation of 9.5 Mg C ha−1 yr−1. After ten years, the rate of accumulation decreased to 2.8 Mg C ha−1 yr−1. However, 40 years after replantation, mangroves were still about 26% lower in C and 15% lower in N compared to our reference forest. The trajectory of recovery of C and N stocks in these forests was different among mangrove components: forest litter recovered rapidly, but downed wood and soil recovered much slower. Programs aimed at reducing C emissions and N pollution should consider that there are temporal lags and ecosystem trade-offs when assessing the effectiveness of mangrove protection and restoration as climate change mitigation strategies
Use of Nonlinear Features for Automated Characterization of Suspicious Ovarian Tumors Using Ultrasound Images in Fuzzy Forest Framework
No full textOvarian cancer is one of the prime causes of mortality in women. Diagnosis of ovarian cancer using ultrasonography is tedious as ovarian tumors exhibit minute clinical and structural differences between the suspicious and non-suspicious classes. Early prediction of ovarian cancer will reduce its growth rate and may save many lives. Computer-aided diagnosis (CAD) is a noninvasive method for finding ovarian cancer in its early stage which can avoid patient anxiety and unnecessary biopsy. This study investigates the efficacy of a novel CAD tool to characterize suspicious ovarian cancer using Radon-transformed nonlinear features. The obtained dimension of the extracted features is reduced using Relief-F feature selection method. In this study, we have employed the fuzzy forest-based ensemble classifier in contrast to the known crisp rule-based classifiers. The proposed method is evaluated using 469 (non-suspicious: 238, suspicious: 231) subjects and achieved a maximum 80.60 ± 0.5% accuracy, 81.40% sensitivity, 76.30% specificity with fuzzy forest, an ensemble fuzzy classifier using thirty-nine features. The proposed method is robust and reproducible as it uses maximum number subjects (469) as compared to state-of-the-art techniques. Hence, it can be used as an assisting tool by gynecologists during their routine screening
The evaluation of mLearning implementation model for English Language learning via Fuzzy Delphi method
No full textThis paper introduces Fuzzy Delphi method as an educational tool to evaluate a technology-mediated education implementation model as part of a larger study. Specifically, the aim of the present study is to evaluate a mLearning implementation model as learning support for undergraduate students in formal language learning which was developed by the authors prior to this study. The study adopted the Fuzzy Delphi method to evaluate the model. Overall, from the findings presented in this paper, as the defuzzification values for all items in the questionnaire exceeded the minimum value of 33.6, the findings conclusively suggest that the participants have consensually agreed to all four aspects of evaluation of the model: 1) suitability of the elements (learning activities), 2) domain classification of the learning activities, 3) relationships among the learning activities, and 4) suitability of the model in teaching and learning activities in assisting students to fulfill their language learning needs and course outcomes. Thus, according to the participants or experts of the study, based on these aspects, the model is suitable to serve as a guide in the implementation of mLearning as learning support for undergraduate formal English language learning for Professional and Communication Skills course. The findings not only serve to introduce mLearning implementation model for language learning but also contribute to how the Fuzzy Delphi method could innovate assessment and evaluation of technology aided learning initiatives like mLearning