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ZnO/Au/ZnO (ZAuZ) multilayer structures with different thicknesses are deposited on a glass substrate by using the RF and DC magnetron sputtering methods and then are used as extended gates in field effect transistors (FET) for the pH detection. Their structural, optical, and electrical properties are investigated. The thickness parameter affected the pH sensitivity of the multilayers, by increasing the sensitivity from 0.25 мA1/2/pH to 0.3мA1/2/pH in the saturation region and from 50 mV/pH to 66.66 mV/pH in the linear region. On the contrary, in the hysteresis voltage case, it is reduced from 10.11 mV to 9.87 mV, as the thickness of multilayers increases from (100/50/100) nm to (200/100/200) nm., ZnO/Au/ZnO (ZAuZ) багатошаровi структури рiзної товщини утворенi РЧ i ПТ-магнетронним розпиленням i потiм використанi як широкий затвор у польовому транзисторi для вимiрювання рН. Дослiджено їх структуру, оптичнi та електричнi властивостi. Товщина структур впливає на рН-чутливiсть, яка росте вiд 0,25 мA1/2/pH до 0,3 мA1/2/pH в областi насичення i вiд 50 мВ/pH до 66,66 мВ/pH на лiнiйнiй дiлянцi на вiдмiну вiд випадку з гiстерезисом, коли чутливiсть зменшується вiд 10,11 мВ до 9,87 мВ, якщо товщина зростає вiд (100/50/100) нм до (200/100/200) нм.

In this work, an MoS2 thin film is used as a modulator in an all-optic polarization modulation system. Polarization modulation is achieved using the thermo-optic effect to modify the refractive index of the MoS2 thin film, changing the polarization state of the incident signal light. A high intensity laser signal is pumped into the MoS2 thin film to generate heat, and due to the thermo-optic effect the refractive index of the MoS2 thin film is modified, causing the polarization state to be modulated accordingly. The azimuth degree is rotated almost linearly with the increase of the pump power and a 70.81° azimuth shift is achieved within the available pump power range. A polarization modulation of 0.1304°/mW with a hysteresis difference of 3.22% is reported in this work. The proposed system has significant potential for use in optical fiber communication systems, optical frequency domain imaging, pulsed lasers and optical signal encoding.

Surface reconstruction of nanostructured solar cell has been carried out using lasers. The reconstruction process was conducted throughout two stages. First, texturing the flat surface of an ordinary solar cell by photelectrochemical etching using a laser beam and second; embeds phosphorous layer within the nanostructured surface using Q-switched laser beam. We have also studied the effect of applied current density on the surface morphology using AFM and SEM. Electrical and morphological investigation was also carried out to examine the nanostructured solar cell.

Visual information of outdoor scenery portrays some important messages of atmospheric effects caused by light scattering, absorption and refractive-index fluctuations. These atmospheric effects are well related to some weather conditions such as air pollution, mist, haze, fog, rain and snow. In this digital age, images of outdo or scenes captured by digital camera can be processed digitally to determine these weather conditions. In the last decade, the digital technologies have evolved at a continuously accelerating pace. This has fostered an incredible amount of research and development work on image processing technique. A number of image processing techniques are key elements of applied visual information research. In particular, image registration is a fundamental image processing technique, which has numerous applications to visual information research, in addition the more traditional application domains such as remote sensing. Other image processing techniques, such as image compression, are also relevant to the handling of large numbers of images for visual information research. Image Understanding refers to automated extraction of information from images. In this study, we would like to develop a state-of-art image processing technique to enhance the capability of an internet video surveillance (IVS) camera for real time air quality monitoring. This technique is able to detect particulate matter with diameter less than 10 micrometers (PM10). An empirical algorithm was developed and tested based on the atmospheric characteristic to determine PM10 concentrations using multispectral data obtained from the IVS camera. A program is developed by using this algorithm to determine the real-time air quality information automatically. This development showed that the modern Information and Communications Technologies (ICT) and digital image processing technology could monitor air quality at multi location simultaneously from a central monitoring station.

Lim, H.S.; MatJafri, M.Z.; Abdullah, K., and Asadpour, R., 2013. A two-band algorithm for total suspended solid concentration mapping using THEOS data. Environmental monitoring through the method of traditional ship sampling is time consuming and requires a high survey cost. This study was carried out to investigate the relationship between total suspended solids (TSS) and satellite THEOS data by using a calibrated algorithm. The study area is the seawater region around Penang Island, Malaysia. Water-quality TSS values were collected simultaneously during the acquisition of the satellite imagery and later analyzed in the laboratory. The digital numbers of the corresponding TSS measurements were extracted and converted into reflectance values for algorithm regression. The two-band algorithm used here is based on the reflectance model, which is a function of the inherent optical properties of water, and this in turn can be related to the concentration of its constituents. The developed algorithm wa...