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In this study, a current-mode quadrature sinusoidal oscillator using single current controlled current differencing transconductance amplifier (CCCDTA) and 2 grounded capacitors is proposed. The proposed oscillator can provide 2 sinusoidal output currents with 90 phase difference. The oscillation condition and oscillation frequency can be controlled electronically by adjusting the bias current of the CCCDTA. The oscillator configuration exhibits high output impedance which makes easy to drive loads without using any buffering devices. The use of only grounded capacitors is ideal for integration. The circuit performances are depicted through PSpice simulations, they show good agreement to theoretical assumptions.

Raksuntorn N.,Suan Sunandha Rajabhat University | Du Q.,Mississippi State University
IEEE Geoscience and Remote Sensing Letters | Year: 2010

Nonlinear spectral mixture analysis for hyperspectral imagery is investigated without prior information about the image scene. A simple but effective nonlinear mixture model is adopted, where the multiplication of each pair of endmembers results in a virtual endmember representing multiple scattering effect during pixel construction process. The analysis is followed by linear unmixing for abundance estimation. Due to a large number of nonlinear terms being added in an unknown environment, the following abundance estimation may contain some errors if most of the endmembers do not really participate in the mixture of a pixel. We take advantage of the developed endmember variable linear mixture model (EVLMM) to search the actual endmember set for each pixel, which yields more accurate abundance estimation in terms of smaller pixel reconstruction error, smaller residual counts, and more pixel abundances satisfying sum-to-one and nonnegativity constraints. © 2006 IEEE.

Jomsri P.,Suan Sunandha Rajabhat University
4th International Conference on Innovative Computing Technology, INTECH 2014 and 3rd International Conference on Future Generation Communication Technologies, FGCT 2014 | Year: 2014

Due to wide application of management system, information data grows rapidly. On one hand, people have a large number of information resources. On the other hand, the time cost and difficulty of people finding the proper information increases. To tackle the problems, book recommendation is one of the solutions for university libraries which possess huge volumes of books and reading-intensive users. This paper proposes a library book recommendation system based on user profile loaning and apply association rule to create model. The result shows that new association rule algorithm suitable to apply for recommender book in library. © 2014 IEEE.

Rattanavadi S.,Suan Sunandha Rajabhat University
Key Engineering Materials | Year: 2016

Waste recycling was interested to both industrial and academic sectors. This study focuses on the use of sludge cake from wastewater treatment plant of a cosmetic industry as Magnesium oxide source. Cordierite obtains good chemical corrosion resistance, fine mechanical properties, good thermal conductivity, and most of all low coefficient of thermal expansion (COE) which is needed for ceramics industry. Magnesium is one of the main materials in cordierite, can be attained from different sources. In this research, Sludge cake from cosmetic industry was used as Magnesium sources for cordierite synthesis. The raw materials were ground, pressed, and sintered between 1200°C to 1325°C for 1 hour. The samples were investigated by X-ray diffraction technique and tested for thermal shock resistance, firing shrinkage, and water absorption. The XRD patterns showed that the increasing intensity of cordierite phase, the higher firing temperature presented the greater of cordierite phases. The findings were confirmed by the peaks of cordierite at 2θ of 10.41° of samples when fired at 1325°C. It can be concluded that cordierite could be synthesized by using raw material from waste with other commercial raw material in different temperatures. Results showed that the sludge cake from wastewater treatment plant of Cosmetic Industry in Thailand is a promising as raw material and beneficial to Thai ceramics industry in terms of cost saving, competitiveness and environmental. © 2016 Trans Tech Publications, Switzerland.

Thaipratum R.,Suan Sunandha Rajabhat University
Key Engineering Materials | Year: 2016

Today, Use of the natural reducer in the green synthesis of metallic nanoparticles has gained more attention due to the development of eco-friendly technologies in materials science that emphasised in environment-friendly chemicals, solvents and renewable materials. In the present work, bread crust, Browning product of thermally processed bread, extracts have been determined for reducing property by using DPPH and hydroxyl radical scavenging assay. The results showed that bread crust extracts have promising reducing property for the green synthesis of metallic nanoparticles. © 2016 Trans Tech Publications, Switzerland.

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