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Nakhon Nayok, Thailand

Biochars can be used as soil amendments for improving soil properties and crop yield. In this study, a pot experiment was conducted to compare the efficiency of pelleted broiler litter biochar (PBLB) derived from a lab-scale pyrolysis reactor (PBLBL) with that resulted from 200-liter-oil drum kiln (PBLBO). The biochar generated from each reactor was applied to the pot that contained lower organics materials, sandy soil, and grown soybeans cv.Chiangmai-60 (Glycine max [L.] Merr.) at the application rates of 5.00, 10.0, 15.0, and 20.0 t ha-1. The results showed that both types of pyrolysis reactors (PBLBL and PBLBO), at every application rate, significantly improved the physicochemical properties of soil and increased the growth and yield of soybean; their comparison with a control treatment of soybeans is p < 0.05. At the application rate of 15.0 t ha-1 the PBLBL showed the highest soybean yield. The application of PBLBL and PBLBO significantly led to increased pH, soil organic matter, C:N ration, N, P, K, Ca, Mg and CEC. Source

Devine M.T.,University of Limerick | Devine M.T.,Irish Economic and Social Research Institute | Devine M.T.,Trinity College Dublin | Gabriel S.A.,University of Maryland University College | Moryadee S.,Chulachomklao Royal Military Academy
Computers and Operations Research | Year: 2016

In this paper we present a new approach for solving energy market equilibria that is an extension of the classical Nash-Cournot approach. Specifically, besides allowing the market participants to decide on their own decision variables such as production, flows or the like, we allow them to compete in terms of adjusting the data in the problem such as scenario probabilities and costs, consistent with a dynamic, more realistic approach to these markets. Such a problem in its original form is very hard to solve given the product of terms involving decision-dependent data and the variables themselves. Moreover, in its more general form, the players can affect not only each others' objective functions but also the constraint sets of opponents making such a formulation a more complicated instance of generalized Nash problems. This new approach involves solving a sequence of stochastic mixed complementarity (MCP) problems where only partial foresight is used, i.e., a rolling horizon. Each stochastic MCP or roll, involves a look-ahead for a fixed number of time periods with learning on the part of the players to approximate the extended Nash paradigm. Such partial foresight stochastic MCPs also offer a realism advantage over more traditional perfect foresight formulations. Additionally, the rolling-horizon approach offers a computational advantage over scenario-reduction methods as is demonstrated with numerical tests on a natural gas market stochastic MCP. Lastly, we introduce a new concept, the Value of the Rolling Horizon (VoRH) to measure the closeness of different rolling horizon schemes to a perfect foresight benchmark and provide some numerical tests on it using a stylized natural gas market. © 2015 Elsevier Ltd. Source

Promdee K.,Chulalongkorn University | Promdee K.,Chulachomklao Royal Military Academy | Vitidsant T.,Chulalongkorn University
Coke and Chemistry | Year: 2013

In this study, char, bio-oil and gases were synthesized with a continuous pyrolysis process from residual plants consisting of Cogongrass and Manilagrass at temperatures in the range of 400-550°C, with a feed rate of 150, 350, and 550 rpm (r min-1). The product yield calculation showed that the liquid yield was highest at 53.56%, at 350 rpm. After separation of the bio-oil from liquid phase, the bio-oil was found to have components of approximately 33.38%, of which the solid yield (char) was highest at 27.35%, at 350 rpm, and the gas yield was highest at 43.60%, at 150 rpm. This indicates that biomass from residual plants materials produced good yields because of low solid and gas yields while having high liquid yield. © 2013 Allerton Press, Inc. Source

Patjawit A.,Chulachomklao Royal Military Academy | Chinnarasri C.,King Mongkuts University of Technology Thonburi
Journal of Civil Structural Health Monitoring | Year: 2014

In order to execute dam safety planning, it is necessary to develop a method to monitor dam health, which considers and simulates the actual physical failure processes of an embankment dam. The objective of this study is to monitor the behaviour of the earthen dam during the impact of ground force through experimental modal analysis. The model of an earthen dam was constructed on a steel plate, which could be easily moved by input force. Accelerometers were installed on the model in many positions to measure respondent acceleration. The post-processing data were processed to show signs such as natural frequency and mode shape using the least-square complex exponential method. Natural frequency shifts were tracked throughout the testing period and the effects of the varying water levels were identified. During vibration, the effect of liquefaction observed in tests was found to be the first factor to deteriorate on the upstream side of the embankment model. The measurement position of the accelerometer was found to be very important for the health monitoring of the embankment dam. The proposed dam health index is the comparison of acceleration at the crest and the upstream side in both time and frequency domains which can identify damage to the embankment dam. © 2013 Springer-Verlag Berlin Heidelberg. Source

Bobaru F.,University of Nebraska - Lincoln | Duangpanya M.,Chulachomklao Royal Military Academy
Journal of Computational Physics | Year: 2012

We introduce a multidimensional peridynamic formulation for transient heat-transfer. The model does not contain spatial derivatives and uses instead an integral over a region around a material point. By construction, the formulation converges to the classical heat transfer equations in the limit of the horizon (the nonlocal region around a point) going to zero. The new model, however, is suitable for modeling, for example, heat flow in bodies with evolving discontinuities such as growing insulated cracks. We introduce the peridynamic heat flux which exists even at sharp corners or when the isotherms are not smooth surfaces. The peridynamic heat flux coincides with the classical one in simple cases and, in general, it converges to it in the limit of the peridynamic horizon going to zero. We solve test problems and compare results with analytical solutions of the classical model or with other numerical solutions. Convergence to the classical solutions is seen in the limit of the horizon going to zero. We then solve the problem of transient heat flow in a plate in which insulated cracks grow and intersect thus changing the heat flow patterns. We also model heat transfer in a fiber-reinforced composite and observe transient but steep thermal gradients at the interfaces between the highly conductive fibers and the low conductivity matrix. Such thermal gradients can lead to delamination cracks in composites from thermal fatigue. The formulation may be used to, for example, evaluate effective thermal conductivities in bodies with an evolving distribution of insulating or permeable, possibly intersecting, cracks of arbitrary shapes. © 2011 Elsevier Inc. Source

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