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We demonstrate a simple optical based humidity sensor using a micro cavity. The micro cavity consists of single mode fiber (SMF-28e, Corning) and a reflective mirror coated with zinc oxide (ZnO) which is embedded in polyvinyl alcohol (PVA). A wideband amplified spontaneous emission (ASE) source, ranging from 1530-1610 nm was injected into the micro cavity. The water molecules from the surface of the ZnO-PVA changed the refractive index of the micro cavity which subsequently modified the phase of ASE light that was reflected from the coated mirror. The change of phase in the reflected light from the coated mirror was monitored with optical spectrum analyzer (OSA). The performance of our optical humidity sensor for non-coated mirror and ZnO-PVA coated mirror was recorded at 0.03 nm/RH% and 0.074 nm/RH%, respectively. This shows that optical humidity sensor with ZnO-PVA coated mirror is more sensitive to humidity changes.

Recent research works on single-walled carbon nanotube (SWCNT) based material has witnessed a great technological importance in photonic applications due to their unique optical characteristics. Present work aims to employ theoretical first principles study to explore the electronic and optical properties of SWCNT in the form of armchair nanotube. The theoretical simulation is done by using density functional theory (DFT) as implemented in the CASTEP computer code. Similar to almost gapless nature of graphene, formation of Fermi level of a relaxed SWCNT structure is found to be at a value approaching zero. The calculated electronic band structure shows a direct band gap of 0.259 eV with Dirac cone form between conduction and valence band. The optical spectrum shows a variation of real and imaginary of dielectric function with inter-band transition taking place along with frequency of the incident light. The absorption spectrum exhibits a significant degree of anisotropic characteristic with almost transparent nature ranging from near infrared to ultraviolet energy range. These optical spectra show excellent nonlinear optical features which remark the suitability in optoelectronic applications.

Sodium chloride (NaCl) is an essential compound that human needs mainly to regulate the amount of water in body. However, the level intake of NaCl daily consumption should wisely be regulated. Previously, various techniques have been employed to measure NaCl concentrations but high cost and complex fabrication become one of the limitations that need to be overcome. Thus, this paper demonstrates a sodium chloride (NaCl) concentration measurement using an optical fiber tip sensor. The flat end facet of single – mode fiber was used to emit the broadband light at near infrared wavelength region to detect NaCl at different concentration ranging from 0% – 4%. The optical power reading was recorded at every increment of 0.5% of NaCl concentration. When the aqueous NaCl was dropped onto the sensing region, the optical power decreases as the NaCl concentration increases. This experiment has shown that the sensitivity achieved by this sensor was 0.1239 dBm/% with regression value up to 0.999.

Building Information Modeling (BIM) has changed the road development industry in the most recent decades. In spite of the fact that there are activities by administration of Malaysia to improve the selection of BIM in road development, yet the usage of BIM is still not true to form because of misty guide of BIM reception plan in Malaysia. Along these lines, it is essential to recognize the issues and difficulties in usage of BIM so as to improve the selection of BIM in this industry. This paper plans to analyze the street development industry in Malaysia to build up an unmistakable comprehension about BIM execution and to give the key arrangements and system for street development industry to expand the reception of BIM in Malaysia. This paper has built up broad BIM understanding which makes ready for the investigation by means of subjective and quantitative technique where the information is gathered through study poll among the street development partners in Malaysia and the gathered information is dissected with Average Index utilizing SPSS Software. The outcomes indicated the degree of current BIM usage in Malaysia street development industry is still extremely low and the issues and difficulties of BIM are distinguished in six zones incorporate specialized, process, legitimate, return of venture, government and individuals. Government has been recognized to assume a significant job in offering help to improve appropriation of BIM in Malaysia. The result of this investigation is communicated as a system for the usage of BIM in Malaysia involving issues that require thought for association to advance on BIM development stepping stool. This investigation clears a firm establishment for association to settle on choice in the appropriation of BIM in street development inside the general association structure.

We demonstrate a passive Q-switched by integrating a Bismuth (III) Telluride (Bi2Te3) dispersed in Polyvinyl Alcohol (PVA) as passive saturable absorber. The experimental works show that the proposed passive saturable absorber operated at input power ranging from 21.69 mW to 126.89 mW with central operating wavelength of 1531 nm. We observe the tunable repetition rate from 40 kHz to 166 kHz with the shortest pulse width of 1.32 μs. The laser produced maximum instantaneous output peak power and pulse energy of 1.62 mW and 11.2 nJ, respectively. The signal to noise ratio was measured at 49 dB which indicates the stability of the generated pulse.