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Natural Science 2011年第6期3卷 484-487页

作者： Nasri A Hamid mohd yusri abd rahman Noor Fairuz Shamsudin Department of Engineering Sciences & Mathematics College of Engineering Universiti Tenaga Nasional Kajang Selangor Malaysia

In this work, 3% to 8% (in weight) of nanosize MgO particles was added to Bi2Sr2CaCu2O8 (Bi- 2212) high-temperature superconductor to fab-ricate Bi-2212 superconducting material with superior mechanical properties. The mechanical strength of the samples was studied by con-ducting the compression test at room tempera-ture, and the addition of 5% nanosize MgO par-ticles produced the highest strength when com- pared with other samples. The sample with 5% MgO addition also exhibited superior super-conducting properties. The Bi-2212 powder with 5% nanosize MgO addition was used to fabricate Bi-2212 tapes through the dip-coating-then- stacking method. The fully processed tapes were investigated via dc electrical resistance measurements, XRD patterns, SEM micrographs, transport critical current density and tensile tests. The tensile tests were conducted at room and cryogenic (77 K) temperatures. Results of tensile tests and Young’s modulus for the tapes showed that the Bi-2212 tapes with nanosize MgO addition recorded better mechanical prop-erty compared to the non-added samples both at room and cryogenic temperatures. The double- core tape with 5% MgO addition recorded the highest failure point at 160 MPa. In addition to the strengthening effect that was observed in the nanosize MgO added Bi-2212 superconduc-tor tapes, the superconducting properties re-mained intact in the tapes.

关键词： Bi-2212 Superconductor Electrical Properties Mechanical Properties High Current Density Cryogenic Temperature

Investigation on the performance of DI-BSCCO superconducting electric motor

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Natural Science 2011年第1期3卷 36-41页

作者： Chin Kat Meng Nasri A. Hamid mohd. yusri abd. rahman 不详

Superconducting electrical devices have been developed in various fields especially in industrial energy over a decade. Superconducting motor is one of the electrical devices that attracted the attention of engineers and researchers from the universities and industries due to its distinctive energy efficiency. This paper describes the performance of superconducting electric motor and its performance was compared with conventional copper electric motor. Direct current (DC) synchronous single- phase series motor has been chosen as the base for development of both motors. Two prototypes of electric motor fabricated using conventional copper coil and superconducting coil were developed with similar motor type, design, dimension, and features. The superconducting motor coil was wound using Bi-2223 (DI-BSCCO) Type H wires developed by Sumitomo Electric Industries Limited, Japan. A finite element analysis was performed to get a clear view on flux plots of the magnetic induction. Features of the superconducting motor and the special coil frame designed to protect the superconducting wire was also presented in this paper. In addition, the torque performances for both types of motor were measured. The superconducting electric motor was found to consume lower power to produce the same output compared with the conventional copper-wound motor.

关键词： Superconductor Magnetic flux Finite Element Analysis Electric Motor

Solid polymeric electrolyte of poly(ethylene)oxide-50% epoxidized natural rubber-lithium triflate (PEO-ENR50-LiCF3SO3)

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Natural Science 2010年第3期2卷 190-196页

作者： Siti Aminah bt. mohd Noor Azizan Ahmad mohd. yusri bin abd. rahman Ibrahim Abu Talib 不详

A solid polymer electrolyte (SPE) films consist-ing of polyethylene oxide (PEO), 50% epoxi-dized natural rubber (ENR50) and LiCF3SO3 with various compositions of PEO-ENR50 and vari-ous weight percentage of LiCF3SO3 were pre-pared by solution casting technique. The poly-mer electrolyte films were characterized using DSC, XRD and AC impedance spectroscopy. The SPE with the PEO-ENR50 composition of 70-30 shows the highest conductivity of 4.2 × 10-5 Scm-1 at the 15 wt.% of LiCF3SO3 compared with the other composition of PEO/ENR50. This composition was then chosen to investigate the effect of LiCF3SO3 on the thermal property, structure and conductivity of the electrolyte. The highest room temperature conductivity of 1.4 × 10-4 Scm-1 was achieved at 20 wt.% of LiCF3SO3. The conductivity result is supported by the DSC and XRD analysis which showed the semi- crystalline nature of PEO turning to amor-phous state due to the increase in LiCF3SO3 content.

关键词： A. Polymers C. Differential Scanning Calorimetry (DSC) C. X-Ray Diffraction D. Electrical Conductivity D. Electrical Properties

Mechanical and superconducting properties of nanosize MgO added dip-coated Bi 2 Sr 2 CaCu 2 O 8 superconducting tape

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Investigation on the performance of DI-BSCCO superconducting electric motor

Natural Science（自然科学期刊） 2011年第6期

作者： Nasri A Hamid mohd yusri abd rahman Noor Fairuz Shamsudin

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Solid polymeric electrolyte of poly(ethylene)oxide-50% epoxidized natural rubber-lithium triflate (PEO-ENR50-LiCF3SO3)

Natural Science（自然科学期刊） 2011年第1期

作者： Chin Kat Meng Nasri A. Hamid mohd. yusri abd. rahman

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Quran memorisation and heart rate variability:How do they correlate?

Natural Science（自然科学期刊） 2010年第3期

作者： Siti Aminah bt. mohd Noor Azizan Ahmad mohd. yusri bin abd. rahman Ibrahim Abu Talib

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World Journal of Clinical Cases 2024年第29期12卷 6275-6284页

作者： Ahmad Rohi Ghazali Nor Malia abd Warif Noor Anisah A Yazit Norsham Juliana Ismarulyusda Ishak Farah Wahida Ibrahim Arimi Fitri Mat Ludin Dzalani Harun Santibuana abd rahman Wan Nor Atikah Che Wan mohd Rozali Biomedical Science Programme Faculty of Health SciencesUniversiti Kebangsaan MalaysiaKuala Lumpur 50300Malaysia Center for Toxicology and Health Risk Studies Faculty of Health SciencesUniversiti Kebangsaan MalaysiaKuala Lumpur 50300Malaysia Faculty of Medicine and Health Sciences Universiti Sains Islam MalaysiaNilai 71800Malaysia Center for Healthy Ageing and Wellness Faculty of Health SciencesUniversiti Kebangsaan MalaysiaKuala Lumpur 50300Malaysia Center for Rehabilitation and Special Needs Studies Faculty of Health SciencesUniversiti Kebangsaan MalaysiaKuala Lumpur 50300Malaysia Occupational Therapy Programme Faculty of Health SciencesUniversiti Kebangsaan MalaysiaKuala Lumpur 50300Malaysia Faculty of Pharmacy and Health Sciences Universiti Kuala Lumpur Royal College of Medicine PerakIpoh Perak 30450Malaysia

BACKGROUND Heart rate variability(HRV)was shown to be affected by performing religious *** To examine the relationship between the level of Quran(the holy book of Muslims)memorisation and HRV among *** This experimental study included 16 Tahfiz students and 16 non-Tahfiz students(n=32).The HRV was measured in three tasks:Recalling familiar verses,memorising new verses,and recalling the newly memorised verses of the *** analysis was done using these parameters:Standard deviation of N-N(heartbeat peak)interval;low frequency(LF);high frequency(HF)and LF/HF *** There were significant differences between tasks for all parameters(P<0.05).However,between the groups,only the LF/HF ratio had significant differences,with F=5.04,P<*** correlation showed a moderate positive correlation between the number of pages memorised and the LF/HF ratio(r=0.61,P<0.05).CONCLUSION Quran memorisation increased the HRV and our results suggested that this activity could be developed as an effective sympathovagal modulation training activity.

关键词： Heart rate variability Autonomic nervous system Quran memorisation Tahfiz student Heartbeat

An Improved Hybrid Indoor Positioning Algorithm via QPSO and MLP Signal Weighting

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Computers, Materials & Continua 2023年第1期74卷 379-397页

作者： Edgar Scavino mohd Amiruddin abd rahman Zahid Farid Department of Physics Faculty of ScienceUniversiti Putra MalaysiaUPM Serdang43400Malaysia Department of Electrical Engineering Abasyn UniversityKhyber-PakhtunkhwaPakistan

Accurate location or positioning of people and self-driven devices in large indoor environments has become an important necessity The application of increasingly automated self-operating moving transportation units,in large indoor spaces demands a precise knowledge of their *** like WiFi and Bluetooth,despite their low-cost and availability,are sensitive to signal noise and fading *** these reasons,a hybrid approach,which uses two different signal sources,has proven to be more resilient and accurate for the positioning determination in indoor ***,this paper proposes an improved hybrid technique to implement a fingerprinting based indoor positioning,using Received Signal Strength information from available Wireless Local Area Network access points,together with the Wireless Sensor Networks *** signals were recorded on a regular grid of anchor points,covering the research *** optimization was performed by relative signal weighting,to minimize the average positioning error over the research *** optimization process was conducted using a standard Quantum Particle Swarm Optimization,while the position error estimate for all given sets of weighted signals was performed using aMultilayer Perceptron(MLP)neural *** to our previous research works,the MLP architecture was improved to three hidden layers and its learning parameters were finely *** experimental results led to the 20%reduction of the positioning error when a suitable set of signal weights was calculated in the optimization *** final achieved value of 0.725 m of the location incertitude shows a sensible improvement compared to our previous results.

关键词： QPSO indoor localization fingerprinting neural networks WiFi WSN

Optical Code Generating Device Using 1×N Asymmetric Hollow Waveguide Couplers

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光子学报 2008年第5期37卷 849-854页

作者： Abang Annuar EHSAN Sahbudin SHAARI mohd Kamil abd. rahman Kee mohd Rafique KEE ZAINAL ABIDIN Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Malaysia Faculty of Applied Science Universiti Teknologi MARA 40450 Shah Alam Selangor Malaysia Kulliyyah of Science International Islamic University Malaysia P. 0 t3oJ＂ 141 25710 Kuantan Pahang Darul Makmur Malaysia)

An optical code generating device for security access system application is presented. The code generating device constructed using asymmetric hollow optical waveguide coupler design provides a unique series of output light intensities which are successively used as an optical code. The design of the waveguide is made using two major components which are asymmetric Y-junction splitter and a linear taper. Waveguiding is done using a hollow waveguide structure. Construction of higher level 1×N hollow waveguide coupler is done utilizing a basic 1×2 asymmetric waveguide coupler design together with a cascaded design scheme. Non-sequential ray tracing of the asymmetric hollow optical waveguide couplers is performed to predict the optical transmission properties of the waveguide. A representation of the code combination that can be generated from the device is obtained using combinatory number theory.

关键词：光代码光子波导耦合器安全接入系统

Deep-piRNA:Bi-Layered Prediction Model for PIWI-Interacting RNA Using Discriminative Features

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Computers, Materials & Continua 2022年第8期72卷 2243-2258页

作者： Salman Khan Mukhtaj Khan Nadeem Iqbal mohd Amiruddin abd rahman Muhammad Khalis abdul Karim Department of Computer Science Abdul Wali Khan University MardanKhyber Pakhtunkhwa23200Pakistan Department of Information Technology University of HaripurKhyber Pakhtunkhwa22620Pakistan Faculty of Science Universiti Putra MalaysiaUPM Serdang43400Malaysia

Piwi-interacting Ribonucleic acids(piRNAs)molecule is a wellknown subclass of small non-codingRNAmolecules that are mainly responsible for maintaining genome integrity,regulating gene expression,and germline stem cell maintenance by suppressing transposon *** piRNAs molecule can be used for the diagnosis of multiple tumor types and drug *** to the vital roles of the piRNA in computational biology,the identification of piRNAs has become an important area of research in computational *** paper proposes a two-layer predictor to improve the prediction of piRNAs and their function using deep learning *** proposed model applies various feature extraction methods to consider both structure information and physicochemical properties of the biological sequences during the feature extraction *** outcome of the proposed model is extensively evaluated using the k-fold cross-validation *** evaluation result shows that the proposed predictor performed better than the existing models with accuracy improvement of 7.59%and 2.81%at layer I and layer II *** is anticipated that the proposed model could be a beneficial tool for cancer diagnosis and precision medicine.

关键词： Deep neural network DNC TNC CKSNAP PseDPC cancer discovery Piwi-interacting RNAs Deep-piRNA