Nakhon Sawan, Thailand

Time filter

Source Type

Khongdee T.,Nakhon Sawan Rajabhat University | Sripoon S.,Nakhon Sawan Rajabhat University | Vajrabukka C.,Kasetsart University
International Journal of Biometeorology | Year: 2013

The objective of the experiments reported here was to measure the effects of cooling techniques (Modified roof vs Normal roof) on the performance and physiology of 12 young male buffaloes with a similar live weight of 160 kg. The study was conducted at Chainat Agriculture and Technology College, Chainat Province, Thailand. The animals were divided randomly into two groups, each group comprising six buffaloes, and the two groups were studied to evaluate the effects of modified roofing (normal roof fitted with woven polypropylene shade cloth) on the subjects' physiological responses to heat stress under hot humid conditions. The modified roof resulted in lowered heat stress in buffaloes compared to those under a standard roof. The difference was shown by the buffaloes having a significantly lower mean rectal temperature (39. 14 ± 0. 07 vs 40. 00 ± 0. 10°C) and plasma cortisol (2. 14 ± 0. 24 vs 3. 38 ± 0. 37 ng/ml). The average daily water consumption was significantly lower in the MR group (MR, 29. 71 ± 0. 86 vs NR, 34. 14 ± 1. 06 L head -1 day-1), while there was a tendency for the roughage intake to be higher in the MR group compared to that of the NR group (MR, 5. 88 ± 0. 18 vs NR, 6. 44 ± 0. 19 kg head-1 -1 day-1; P = 0. 0508). It was concluded that roof modification facilitated a reduction in heat load from roof re-radiation, and was an effective means of alleviating thermal stress in young buffaloes. © 2012 ISB.


Choogorn T.,Nakhon Sawan Rajabhat University | Mahattanakul J.,Mahanakorn University of Technology
IET Circuits, Devices and Systems | Year: 2013

This study presents distortion analysis of the fully differential Gm-C filters in which the imbalance of the differential input voltages is taken into consideration. Closed-form equations expressing distortions of differential-mode (DM) output voltages as functions of DM and common-mode input voltages are developed. It was found that the HD3 of the DM output voltage is independent of the input imbalance. On the contrary, the HD2 of the DM output voltage is directly dependent upon the input imbalance. Simulation results are shown to be in good agreement with the analytical results. © The Institution of Engineering and Technology 2013.


Su C.-C.,Chia Nan University of Pharmacy and Science | Pukdee-Asa M.,Nakhon Sawan Rajabhat University | Ratanatamskul C.,Chulalongkorn University | Lu M.-C.,Chia Nan University of Pharmacy and Science
Separation and Purification Technology | Year: 2011

This study investigated the treatment of textile industrial wastewater from a dyeing and finishing mill by the fluidized-bed Fenton process. Operating variables, such as the pH, concentrations of H2O2 and Fe2+, are used to explore the respective effects on the oxidation and decolorization of the textile wastewater. The experimental results were estimated in terms of chemical oxygen demand (COD) and color reductions to examine the treatment efficiency. The optimum pH was observed to be around 3. The decolorization and the oxidation efficiencies could achieve 92% and 49%, respectively, in only 2 min of reaction under the concentration ratio of [COD]:[Fe2+]:[H2O2] = 1:0.95:3.17. By using this process, the oxidation of textile wastewater increased with increasing H2O2 dosage. The highest level of oxidation was 87%. © 2011 Elsevier B.V. All rights reserved.


Khankasikam K.,Nakhon Sawan Rajabhat University
7th International Conference on Digital Information Management, ICDIM 2012 | Year: 2012

The objective of this research is to investigate the feasibility of using Conway's game of life to solve the problem on printed Lanna character recognition. Pattern recognition can be defined as the objects identification on the basis of information available about it. The problem on character recognition has been discussed to find out the best solution and various recognition methods have been implemented. Conway's game of life has a capability to generate a new identity pattern, which is a stable state, from predefined pattern. The proposed framework consists of three modules: preparation, training and recognition. The experiments are carried on 1,200 printed Lanna characters, which randomly selected from documents written in Lanna language. The system performs the number of match 1,142 characters or 95.15%, while mismatch 27 characters or 2.25% and rejecting 31 characters or 2.58%. © 2012 IEEE.


Khankasikam K.,Nakhon Sawan Rajabhat University
Journal of Information Science and Engineering | Year: 2014

Binary image is the essential format for document image processing, and the operation of the subsequent steps depends on the quality of the binarization process. The objective of this research is to propose a new binarization method based on adaptive multilayer- information for restoration of degraded historical document images. This paper focuses on degraded Thai historical document images, which are in the form of handwritten and machine-printed documents images. The proposed method consists of five stages including noise elimination, majority pixel analysis, degradation of the background layer estimation, thresholding and vicinity analysis. The experiments are performed on 480 degraded Thai historical document images provided by National Library of Thailand. The experimental results demonstrate that the proposed method performs better than five well-known adaptive binarization methods.


Khankasikam K.,Nakhon Sawan Rajabhat University
Applied Mechanics and Materials | Year: 2013

The objective of this paper is to develop methodology that can recognize the Lanna handwritten character on historical documents by using character feature extraction technique. Historical documents are national treasures. Insignificant effort has been made to preserve Lanna historical documents. Other nations such as Egypt, China and Greece are investing a large effort in restoring and preserving their national historical documents. As a starting point, the focus is on using one Lanna historical document for performing experiments and verifying recognition methods available in this research area. The proposed system consists of three modules, which are image preprocessing module, feature extraction module and character recognition module. The details of each module are following: first, the input image is transformed into a suitable image for feature extraction module. Second, the proposed system extracts character features from the image. Finally, the extracted character information, which is kept in form of bit string, is calculated a similarity value for recognition result. The experiment was conducted on more than 4,000 Lanna handwritten characters by using 10-fold cross-validation classification method which is using 3,600 for training characters and 400 for testing character. The cross-validation process is repeated 10 times, with each of the 10 subsets used exactly once as the validation data. The precision of the proposed system is around 89.73 percent. © (2013) Trans Tech Publications, Switzerland.


Nai-Arun N.,Nakhon Sawan Rajabhat University | Moungmai R.,Nakhon Sawan Rajabhat University
Procedia Computer Science | Year: 2015

This paper applied a use of algorithms to classify the risk of diabetes mellitus. Four well known classification models that are Decision Tree, Artificial Neural Networks, Logistic Regression and Naive Bayes were first examined. Then, Bagging and Boosting techniques were investigated for improving the robustness of such models. Additionally, Random Forest was not ignored to evaluate in the study. Findings suggest that the best performance of disease risk classification is Random Forest algorithm. Therefore, its model was used to create a web application for predicting a class of the diabetes risk. © 2015 The Authors.


Sirisamphanwong C.,Nakhon Sawan Rajabhat University | Ketjoy N.,Naresuan University
Renewable Energy | Year: 2012

This paper presents the effects of spectral irradiance distribution on the performance of polycrystalline (p-Si) and amorphous silicon (a-Si) photovoltaic (PV) modules under Thai climatic conditions. The annual outdoor solar spectrum measurements bouncing on the PV modules installed at Energy Park, School of Renewable Energy Technology (SERT), Naresuan University, Thailand revealed that the average photon energy (APE) of total incident solar irradiance was 50% higher than that at standard test conditions. The results show that the power output of a-Si PV module mainly depends on spectrum distribution. In contrast, the power output of p-Si is not sensitive to spectrum distribution. Because of the different spectrum response of p-Si and a-Si PV modules, the actual irradiance spectrum data of each location under real working conditions are necessary for optimizing PV design. © 2011 Elsevier Ltd.


Loser C.,TU Dresden | Urit T.,Nakhon Sawan Rajabhat University | Bley T.,TU Dresden
Applied Microbiology and Biotechnology | Year: 2014

Ethyl acetate is an environmentally friendly solvent with many industrial applications. The production of ethyl acetate currently proceeds by energy-intensive petrochemical processes which are based on natural gas and crude oil without exception. Microbial synthesis of ethyl acetate could become an interesting alternative. The formation of esters as aroma compounds in food has been repeatedly reviewed, but a survey which deals with microbial synthesis of ethyl acetate as a bulk product is missing. The ability of yeasts for producing larger amounts of this ester is known for a long time. In the past, this potential was mainly of scientific interest, but in the future, it could be applied to large-scale ester production from renewable raw materials. Pichia anomala, Candida utilis, and Kluyveromyces marxianus are yeasts which convert sugar into ethyl acetate with a high yield where the latter is the most promising one. Special attention was paid to the mechanism of ester synthesis including regulatory aspects and to the maximum and expectable yield. Synthesis of much ethyl acetate requires oxygen which is usually supplied by aeration. Ethyl acetate is highly volatile so that aeration results in its phase transfer and stripping. This stripping process cannot be avoided but requires adequate handling during experimentation and offers a chance for a cost-efficient process-integrated recovery of the synthesized ester. © 2014 Springer-Verlag.


Urit T.,TU Dresden | Urit T.,Nakhon Sawan Rajabhat University | Li M.,TU Dresden | Bley T.,TU Dresden | Loser C.,TU Dresden
Applied Microbiology and Biotechnology | Year: 2013

Conversion of lactose into ethyl acetate by Kluyveromyces marxianus allows economic reuse of wheyborne sugar. The high volatility of ethyl acetate enables its process-integrated recovery by stripping. This stripping is governed by both the aeration rate and the partition coefficient, KEA,L/G. Cultivation at elevated temperatures should decrease the KEA,L/G value and thus favor stripping. K. marxianus DSM 5422 as a potent producer of ethyl acetate was cultivated aerobically in whey-borne media for studying temperature-dependent growth and ester formation. Shake flask cultivation proved thermal tolerance of this yeast growing from 7 to 47 °C with a maximum rate of 0.75 h-1 at 40 °C. The biomass yield was 0.41 g/g at moderate temperatures while low and high temperatures caused distinct drops. The observed μ-T and YX/S-T dependencies were described by mathematical models. Further cultivations were done in an 1-L stirred reactor for exploring the effect of temperature on ester synthesis. Cultivation at 32 °C caused significant ester formation (YEA/S=0.197 g/g) while cultivation at 42 °C suppressed ester synthesis (YEA/S=0.002 g/g). The high temperature affected metal dissolution from the bioreactor delivering iron for yeast growth and preventing ester synthesis. Cultivation at 32 °C with a switch to 42 °C at the onset of ester synthesis allowed quick and efficient ester production (YEA/S= 0.289 g/g). The high temperature lowered the KEA,L/G value from 78 to 44 L/L which heightened the gas-phase ester concentration (favoring ester recovery) without increasing the liquid-phase concentration (avoiding product inhibition). © Springer-Verlag Berlin Heidelberg 2013.

Loading Nakhon Sawan Rajabhat University collaborators
Loading Nakhon Sawan Rajabhat University collaborators