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Graphene Nanoplatelets (GnP)-PVA Based Passive Saturable Absorber Nabihah Hussin; Mohd Haniff Ibrahim; Fauzan Ahmad; Hafizal Yahaya; Sulaiman Wadi Harun
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 15, No 2: June 2017
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v15i2.6126

Abstract

A passive Q-switched pulsed laser at 1.5 m region incorporating graphene nanoplatelets (GnPs) embedded in Polyvinyl Alcohol (PVA) is demonstrated. A surfactant is used to aid the dispersion of the GnPs before it is mixed with PVA to develop a GnPs-PVA film based SA. The SA is integrated into the laser cavity by attaching a cut of the GnPs-PVA film in between two fiber ferrule of the laser ring cavity.The proposed GnPs-PVA film based passive Q–switched laser was able to operate as the input pump power was increased from 39 mW up to a maximum of 148 mW before diminishing. The laser obtained operated with a central wavelength of 1530.76 nm. Repetition rates were obtained at 33 kHz to 91.5 kHz, throughout the tunable input pump power with the shortest pulse width of 2.42 s. Maximum attainable peak power and pulse energy of 1.2 mW and 5.9 nJ, respectively, was recorded, accompanied by a signal to noise ratio (SNR) of 28 dB.
Discrete liquid level fiber sensor Muhammad Yusof Mohd Noor; Ahmad Sharmi Abdullah; Asrul Izam Azmi; Mohd Haniff Ibrahim; Mohd Rashidi Salim; Norazan Kassim
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 4: August 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i4.12769

Abstract

A novel simple fiber sensor to sense liquid level is presented. The operation principle is based on the relative Fresnel reflective intensity. The sensor consists of a fiber splitter with the configuration of one input to multiple fiber outputs, i.e. 1×4, 1×8 and 1×12 arrangements that act as a discrete liquid level. A broadband source (BBS) is used as the light source supply. The total reflected power intensity is measured using a power meter. Experimental results show that the power intensity decreases as the level of liquid is increased. The sensor has a simple configuration, low cost, and it can be customized for a wide height measurement range spanning from a few centimeters up to a hundred meters.
Varying Effects of Temperature and Path-length on Ozone Absorption Cross-Section Enenche Patrick; Michael David; A.O. Caroline; Mohd Haniff Ibrahim; Sevia Mahdaliza Idrus; Tay Ching En Marcus
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 16, No 2: April 2018
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v16i2.8577

Abstract

Inconsistencies in the absorption cross section of ozone have been observed. Hence, for accurate measurement, we have reported the combined effects of varying optical path-length and temperature on the ozone gas absorption cross section (OACS) at 334.15nm. Adopting optical absorption spectroscopy, results of the (OACS) have been simulated using spectralcalc simulator with HITRAN 12 has the latest line list. OACS increased by 52.27% as the temperature increased from 100K to 350K while it was slightly affected by a 0.007% decrease varying the path-length from 0.75cm-130cm.
Fundamental Review to Ozone Gas Sensing Using Optical Fibre Sensors Michael David; Mohd Haniff Ibrahim; Sevia Mahdaliza Idrus; Tay Ching En Marcus
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 13, No 4: December 2015
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v13i4.2047

Abstract

The manuscript is a review of basic essentials to ozone gas sensing with optical methods. Optical methods are employed to monitor optical absorption, emission, reflectance and scattering of gas samples at specific wavelengths of light spectrum. In the light of their importance in numerous disciplines in analytical sciences, necessary integral information that serves both as a basis and reference material for intending researchers and others in the field is inevitable. This review provides insight into necessary essentials to gas sensing with optical fibre sensors. Ozone gas is chosen as a reference gas. Simulation results for ozone gas absorption cross section in the ultraviolet (UV) region of the spectrum using spectralcalc.com simulation have also been included.
A low-cost fiber based displacement sensor for industrial applications Siti Mahfuza Saimon; Nor Hafizah Ngajikin; Muhammad Shafiq Omar; Mohd Haniff Ibrahim; Muhammad Yusof Mohd Noor; Ahmad Sharmi Abdullah; Mohd Rashidi Salim
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 17, No 2: April 2019
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v17i2.9754

Abstract

In this paper, a low-cost fiber optic displacement sensor (FODS) using a bundle of plastic optical fiber (POF) as a probe is developed and presented. The sensor consists of a high power light emitting diode (LED) as light source, a probe with multiple receiving plastic optical fiber and a photodiode detector. The sensor is characterized at millimeter distance and the sensor output is analyzed from 0 mm to 13 mm displacement. The sensitivity of the sensor is found to be 5.38 mV/mm over 2.6 mm sensing range. The sensor is very useful for close distance target since it is highly sensitive at the front slope. The low development cost, high degree of sensitivity and simplicity of the design make it suitable for wide range of industrial applications.
The concurrent upshot of optical path-length and pressure on O3 absorption cross-section in relation to green communication Michael David; Patrick Enenche; Caroline O. Alenoghena; Mohd Haniff Ibrahim; Sevia M. Idrus; Tay Ching En Marcus
International Journal of Advances in Applied Sciences Vol 11, No 2: June 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (872.067 KB) | DOI: 10.11591/ijaas.v11.i2.pp97-106

Abstract

Ozone gas is a greenhouse gas. Accurate measurement of its concentration is dependent on the right value of the ozone gas absorption cross-section. In the literature, discrepancies and inconsistencies have been however linked with ozone gas absorption cross-section. In the literature, information on the pressure effect on pressures less than 100 mbar and greater than 100 but less than 1000 mbar is not available for the visible spectrum. Thus, creating an information gap that this manuscript is intended to fill up. This is the problem that has been addressed in this present work. The method of simulation with SpectralCalc is the method adopted for the present work. HITRAN 2012 simulator, available on spectralcalc.com, was used in simulating the ozone gas absorption cross-section to determine the simultaneous effect of optical path length and pressure at two peak wavelengths in the visible spectrum. Simulation outcomes were obtained for an optical path length of 10 cm to 120 cm showing that the optimum absorption cross-section value of 5.1084×10-25 m2/molecule at 603 nm and 4.7182×10-25 m2/molecule at 575 nm for gas cells length between 10 cm and 120 cm are obtained at peak points. Pressure values at which ozone gas absorption cross-section becomes a constant value of 5.1058×10-25 m2/molecule at 603 nm and 4.7158×10-25 m2/molecule at 575 nm is optical path length dependent. The percentage difference between 5.1084×10-25 m2/molecule and 5.1058×10-25 m2/molecule is 0.05% for all lengths of gas cells considered. Similarly, the percentage difference between 4.7182×10-25 m2/molecule and 4.7158×10-25 m2/molecule is also 0.05% for all lengths of gas cells considered. These results are relevant for high-accuracy and high-precision ozone gas measurements. Furthermore, efficient measurement of ozone gas is a direct enhancement of green communication.
Graphene-polyvinyl alcohol polymer based saturable absorption at 2000 nm region Nabihah Hussin; Asrul Izam Azmi; Mohd Rashidi Salim; Muhammad Yusof Mohd Noor; Ahmad Sharmi Abdullah; Michael David; Fauzan Ahmad; Mohd Haniff Ibrahim
Indonesian Journal of Electrical Engineering and Computer Science Vol 27, No 2: August 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v27.i2.pp701-708

Abstract

A graphene-polyvinyl alcohol (PVA) composite saturable absorption is demonstrated at 2000 nm region. Graphene suspension is produced using low-cost electrochemical exfoliation process. The suspension is mixed with PVA host polymer in 1:1 ratio and left evaporated at room temperature which finally produced graphene-PVA thin film. Thulium doped fiber (TDF) gain medium has been shown to produce a stable Q-switched pulse with a highest repetition rate of 54 kHz, a short pulse duration of 2.89 µs, a maximum peak power of 16 mW, and an estimated maximum pulse energy of 49 nJ. Apparently, at 2000 nm region, superior performances of graphene-PVA composite have been recorded which was largely contributed by meticulous composite preparation and homogenous mixture with PVA host.
A New Ozone Concentration Regulator Michael David; Tay Ching En Marcus; Maslina Yaacob; Mohd Rashidi Salim; Nabihah Hussin; Mohd Haniff Ibrahim; Sevia Mahdaliza Idrus; Nor Hafizah Ngajikin; Asrul Izam Azmi
Indonesian Journal of Electrical Engineering and Computer Science Vol 13, No 2: February 2015
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Laboratory design of an ozoneconcentration regulator which is build on the theory of continuity equation forgas flow in parallel pipes in conjunction with the ozone elimination potentialsof an ozone destructor is presented. At an initial oxygen flow rate of 33.33 cm3s-1,ozone concentration was  generated andvaried between 429.30 parts per million (ppm) to 3826.60 ppm.  Similarly at an initial oxygen flow rate of 25cm3s-1, ozone concentration was  generated and varied between 387.30 ppm to4435.20 ppm. Effect of flow meter when the ozone concentration was set toapproximate 1000 ppm  were investigatedand reported. Fine tuning of the regulator is necessary to ensureconcentration stability for long duration experimental work. DOI: http://dx.doi.org/10.11591/telkomnika.v13i2.6952