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Agricultural settings present unique challenges for the transmission of huge amounts of images over long-range wireless networks. It is challenging to remotely gather data for transmission over a wireless network in research areas due to a lack of basic amenities like internet connections, especially in distant agricultural areas. In this research, the Fast Fourier Transform (FFT) method was used in conjunction with the Discrete Cosine Transform (DCT) method of image compression to achieve a higher compression ratio. In order for a Wireless Sensor Network (WSN) to provide compressed image data to a wireless based station, a LoRaWAN network has been identified. Low-power LoRaWAN networks may regularly transmit compressed images from an agricultural region to a monitoring system up to 15 km away. Images of golden apple snails were collected for this study from a variety of sources. The procedure was coded in MATLAB so that it could be run with input images being judged by the created algorithm. The input images can be compressed with a range of compression ratios (CR) from 3.00 to 50.00, as shown by the simulation results. Compressed image quality is measured not only by the above-mentioned criteria, but also by Mean Square Error (MSE) and Peak Signal to Noise Ratio (PSNR). According to the numbers, the best achievable compression ratio is 49.04, with an MSE of 172.72 and a PSNR of 25.75 at its highest. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) has been acknowledged as a promising photocatalyst in environmental remediation including wastewater treatment. In this study, TiO2 nanoparticles either by single or co-doped of iron (Fe) and nitrogen (N) via sol-gel method and calcined at 500 °C for 3 hours. This experiment investigated the performance of mono/co-dopant of TiO2 photocatalyst against methyl orange in aqueous solution under UV light irradiation. The experimental results showed the rate of degradation favored in co-doped TiO2 followed by mono doped TiO2 and pristine TiO2. The photocatalytic reaction followed pseudo first-order kinetics which were rationalized in terms of the Langmuir– Hinshelwood model and provided nearly complete degradation. [ABSTRACT FROM AUTHOR]

Zinc Oxide (ZnO) is an inorganic compound and it is doped with aluminum to increase its capabilities. Aluminum Zinc Oxide (AZO) thin films are semiconductor materials that have band gap energy of 3.3eV. Various method of deposition have been study to growth AZO thin films. It has been extensively use in solar cell application, display application, gas sensing purposes, and thin film transistors (TFTs). In this work, sol gel method and spin coating was used to deposited AZO thin films. The ZnO sol-gel were synthesized using zinc acetate dihydrate as precursor, isopropanol as solvent, diethanolamine as sol stabilizer, and distilled water as oxidation agent. Then, synthesized ZnO were doped with different mole ratio of aluminum nitrate nanohydrate to produced AZO. The glass substrate was used as substrate and AZO thin films were then calcinated at 300°C and 500°C. The characterization of AZO thin film were done using X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), Ultraviolet-visible spectroscopy (UV-Vis), Field Emission Scanning Electron Microscope (FESEM), and Energy Dispersive X-ray spectroscopy (EDX). The XRD results show that the ZnO with hexagonal wurtzite-type structure and temperature does have effect on the film intensity which related to crystallinity of thin films. Through AFM analysis, the value of RMS decreases from 3.018 nm to 2.240 nm as the temperature increases. Meanwhile, from UV-Vis result, it can be seen that AZO thin film have a high transmittance percentage above 90% after wavelength 400 nm with band gap value of 3.3 eV. FESEM image show that the grain boundary of AZO decrease with both parameter (mole ratio and calcinations temperature). Both parameters do have effect on AZO thin film. EDX analysis shows that there are existence of zinc, oxide, and aluminum. [ABSTRACT FROM AUTHOR]

Plasma transfer arc welding (PTAW) is a cermet deposition method that may produce thick coating (up to 3 mm). Cermet deposit by this method has shown high wear and corrosion resistance. The tungsten carbide (WC) content used is 65 wt% to evaluate its morphology, chemical composition and corrosion behavior of the coating. Two techniques have been used to characterise the powders and coatings which are scanning electron microscopy (SEM) and X-ray diffraction (XRD). The potentiodynamic polarization with three electrodes was used to evaluate the corrosion behaviour of the weld-overlay. It is found that, XRD spectrum shows two type of tungsten carbide which are WC and W2C, nickel (Ni) and nickel boride (Ni3B). The corrosion for cermet coating is due to removal of binder follow by carbide detachment. Removal of binder in acidic electrolyte is thicker (44 ± 6 μm) than in alkaline electrolyte (25 ± 2 μm). Although the corrosion current in acidic electrolyte is more positive compares to in alkaline electrolyte, the removal of the binder in acidic electrolyte is higher due to less noble of nickel in the acidic than in alkaline electrolyte. In alkaline electrolyte, W is less noble, but due to large carbide size, the carbide is hard to removed. [ABSTRACT FROM AUTHOR]

We have reported the influence of annealing temperature and heating rate on thermoluminescence (TL) properties of nanocrystalline calcium borate, CaB2O4, powder synthesized by solution combustion method. Powder X-ray diffraction experiments were carried out on CaB2O4 to get the crystal phase and size. The samples were annealed using the TLD oven and exposed to cobalt-60 source. TL glow curves were measured and recorded using a Harshaw model 3500 TLD reader. The crystal phase confirmed one major phase of CaB2O4 with 27 nm in size. CaB2O4 has a simple glow curve with only one and a well defined peak at around 150 °C. TL intensity was higher after annealing the material before irradiation which indicated the importance of annealing. It was found that an annealing temperature at 300 °C for one hour and the heating rate of 10 °C s-1 was the best procedure to produce high TL intensity. [ABSTRACT FROM AUTHOR]

This paper reviews on previous and on-going works relating to the interaction of Eu3+ and Sm3+ used in AGd(1-x)Eux(MO4)2 where (A=Li+, K+ and Na+) and (M=Mo and W) in alkaline metals red phosphors-AGd(1-x)EuxSmy((MO4)2. A literature review in terms of its crystal structures as well its effects on the photoluminescence properties of the phosphor is elucidated herein. The outcome from this review concludes that there is a large possibility that a more efficient red phosphor can be obtained by introducing Sm3+ on AGd(1-x)EuxSmy(MO4)2. [ABSTRACT FROM AUTHOR]

A series of lead manganese borophophate glass samples were prepared and studied to determine the structural and luminescence properties using Fourier Transform Infrared Spectroscopy (FT-IR) and Photoluminescence Spectrophotometer. The glass samples with composition of 20PbO-xMnO2-30B2O3-(50-x)P2O5-2TiO2 where 0 ≤ x ≤ 20 were prepared using melt-quenching technique in air atmosphere. The samples containing different MnO2 and P2O5 content were both subjected to FT-IR testing to show the contrary effects of the network modifier. Infrared absorption spectrum shows vibrational bands of BO4 and PO3 structure within the borophosphate network structure, with the dominant BO units increasing with lower P2O5 mol%. All glassy samples exhibit photoluminescence emission in the visible range. Manganese contained samples shows violet emissions while those without show violet-blue emission when excited by UV. [ABSTRACT FROM AUTHOR]

The SnO2 co-doped lithium potassium borate glasses doped with 0.05, 0.10, 0.25 and 0.50 mol% of Cu were synthesized by the melt quenching technique. The SnO2 co-dope was added to the compounds in the amounts of 0.05, 0.10, and 0.20 mol%. The photoluminescent spectrum for different concentrations of copper was studied. It was observed that the intensity of blue emission (450, 490 nm) varies with concentration mol%. In addition, with different concentration of SnO2 to 0.10 mol% Cu, the influence of the luminescence has been observed to enhance intensity and shifted to blue and red (490, 535 nm) emissions. [ABSTRACT FROM AUTHOR]