The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses, i.e. coarse original rice husk ash （RHA0）, RHA1, RHA2, and RHA3 were used ...The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses, i.e. coarse original rice husk ash （RHA0）, RHA1, RHA2, and RHA3 were used for the study. Ordinary Portland cement （OPC） was partially replaced with rice husk ash at 20% by weight of binder. The water to binder ratio （W/B） of the mortar was maintained at 110%±5% with flow table test. Specific gravity, fineness, chemical properties, compressive strength, and porosity test of mortars were determined. The differences in chemical composition of the rice husk ashes with different finenesses from the same batch are small. The use of RHA3 produces the mortars with good strength and low porosity. The strength of the mortar improves with partial replacement of RHA3 in comparison with normal coarse rice husk ash. The use of RHA3 results in a strong and dense mortar, which is due to the better dispersion and filling effect, as well as an increase in the pozzolanic reaction.展开更多
This paper presented a study on the strength and chloride resistance of mortars made with ternary blends of ordinary Portland cement （OPC）, ground palm oil fuel ash （POA）, and classified fly ash （FA）. The mortar...This paper presented a study on the strength and chloride resistance of mortars made with ternary blends of ordinary Portland cement （OPC）, ground palm oil fuel ash （POA）, and classified fly ash （FA）. The mortar mixtures were made with Portland cement type I containing 0-40wt% FA and POA. FA and POA with 1wt%-3wt% retained on a sieve No.325 were used. The compressive strength and rapid chloride penetration depth of mortars were determined. The results reveal that the use of ternary blended cements produces good strength mortars. The use of the blend of FA and POA also produces high strength mortars and excellent resistance to chloride penetration owing to the synergic effect of FA and POA. A mathematical analysis and two-parameter polynomial model were presented to predict the compressive strength. The mathematical model correlated well with the experimental results. The computer 3-D graphics of strength of the ternary blended mortars were also constructed and could be used to aid the understanding and the proportioning of the blended system.展开更多
Creating a sustainable energy and environment, alternative energy is needed to be developed instead of using fossil fuels. This research describe a comparison of the use of pyrolysis oils which are the tire pyrolysis ...Creating a sustainable energy and environment, alternative energy is needed to be developed instead of using fossil fuels. This research describe a comparison of the use of pyrolysis oils which are the tire pyrolysis oil, plastic pyrolysis oil and diesel oil in the assessment of engine performance, and feasibility analysis. Pyrolysis oils from waste tire and waste plastic are studied to apply with one cylinder multipurpose agriculture diesel engine. It is found that without engine modification, the tire pyrolysis offers better engine performance whereas the heating value of the plastic pyrolysis oil is higher. The plastic pyrolysis oil could improve performance by modifying engine. The economic analysis shows that the pyrolysis oil is able to replace diesel in terms of engine performance and energy output if the price of pyrolysis oil is not greater than 85% of diesel oil.展开更多
This article presents a study on the resistance to chloride penetration, corrosion, porosity, and strength of mortar containing fine fly ash （FA）, ground rice husk-bark ash （RB）, and ground bagasse ash （BA）. Ord...This article presents a study on the resistance to chloride penetration, corrosion, porosity, and strength of mortar containing fine fly ash （FA）, ground rice husk-bark ash （RB）, and ground bagasse ash （BA）. Ordinary Portland cement （CT） was blended with a single pozzolan and two pozzolans. Strength, porosity, rapid chloride penetration, immersion, and corrosion tests were performed to characterize the mortar. Test results showed that the use of ternary blends of CT, FA, and RB or BA decreased the porosity of the mortar, as compared with binary blended mortar containing CT and RB or BA. The resistance to chloride penetration of the mortar improved substantially with partial replacement of CT with FA, RB, and BA. The use of ternary blends of CT, FA and RB or BA produced the mortar with good strength and resistance to chloride penetration. The resistance to chloride penetration was higher with an increase in the replacement level due to the reduced calcium hydroxide.展开更多
A <st1:data language="0" startpos="3" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been...A <st1:data language="0" startpos="3" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">distributed generator is <st1:data language="0" startpos="28" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">a small-scaled <st1:data language="0" startpos="42" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">active <st1:data language="0" startpos="49" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">generating <st1:data language="0" startpos="60" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">unit <st1:data language="0" startpos="65" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">located <st1:data language="0" startpos="73" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in展开更多
This paper analyzes the effects of the voltage across insulator of 69 kV and 24 kV lines installed on the same pole. The case studies illustrated the lightning strike to direct top pole and mid span of ground wire usi...This paper analyzes the effects of the voltage across insulator of 69 kV and 24 kV lines installed on the same pole. The case studies illustrated the lightning strike to direct top pole and mid span of ground wire using the ATP-EMTP （Alternative Transient Program-Electromagnetic Transient Program）. The results found that when lightning strike the voltage across the 69 kV line insulator at mid span is 1.55 times and 1.34 times higher than at top pole when the front time is 0.25/100μs and 10/350 μs, respectively. When lightning strike the voltage across the 24 kV line at mid span is 1.04 times and 0.64 times higher than at top pole when the front time is 0.25/100μs and 10/350μs, respectively. So the effect of lightning strike is more severe at mid span than at the direct top pole, especially for the 69 kV insulator.展开更多
ELD （economic load dispatch） problem is one of the essential issues in power system operation. The objective of solving ELD problem is to allocate the generation output of the committed generating units. The main co...ELD （economic load dispatch） problem is one of the essential issues in power system operation. The objective of solving ELD problem is to allocate the generation output of the committed generating units. The main contribution of this work is to solve the ELD problem concerned with daily load pattern. The proposed solution technique, developed based PSO （particle swarm optimization） algorithm, is applied to search for the optimal schedule of all generations units that can supply the required load demand at minimum fuel cost while satisfying all unit and system operational constraints. The performance of the developed methodology is demonstrated by case studies in test system of six-generation units. The results obtained from the PSO are compared to those achieved from other approaches, such as QP （quadratic programming）, and GA （genetic algorithm）.展开更多
This paper presents an efficient algorithm for optimization of radial distribution systems by a network reconfiguration to balance feeder loads and eliminate overload conditions. The system load-balancing index is use...This paper presents an efficient algorithm for optimization of radial distribution systems by a network reconfiguration to balance feeder loads and eliminate overload conditions. The system load-balancing index is used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal network reconfiguration of load balancing. The tabu search algorithm is employed to search for the optimal network reconfiguration. The basic idea behind the search is a move from a current solution to its neighborhood by effectively utilizing a memory to provide an efficient search for optimality. It presents low computational effort and is able to find good quality configurations. Simulation results for a radial 69-bus system. The study results show that the optimal on/off patterns of the switches can be identified to give the best network reconfiguration involving balancing of feeder loads while respecting all the constraints.展开更多
基金the Commission on Higher Education (MUA) of Thailandthe Sustainable Infrastructure Research and Development Center of Khon Kaen University (SIRDC)Department of Civil Engineering of Rajamangala University of Technology Phra Nakhon (RMUTP)
文摘The effect of grinding on the chemical and physical properties of rice husk ash was studied. Four rice husk ashes with different finenesses, i.e. coarse original rice husk ash （RHA0）, RHA1, RHA2, and RHA3 were used for the study. Ordinary Portland cement （OPC） was partially replaced with rice husk ash at 20% by weight of binder. The water to binder ratio （W/B） of the mortar was maintained at 110%±5% with flow table test. Specific gravity, fineness, chemical properties, compressive strength, and porosity test of mortars were determined. The differences in chemical composition of the rice husk ashes with different finenesses from the same batch are small. The use of RHA3 produces the mortars with good strength and low porosity. The strength of the mortar improves with partial replacement of RHA3 in comparison with normal coarse rice husk ash. The use of RHA3 results in a strong and dense mortar, which is due to the better dispersion and filling effect, as well as an increase in the pozzolanic reaction.
文摘This paper presented a study on the strength and chloride resistance of mortars made with ternary blends of ordinary Portland cement （OPC）, ground palm oil fuel ash （POA）, and classified fly ash （FA）. The mortar mixtures were made with Portland cement type I containing 0-40wt% FA and POA. FA and POA with 1wt%-3wt% retained on a sieve No.325 were used. The compressive strength and rapid chloride penetration depth of mortars were determined. The results reveal that the use of ternary blended cements produces good strength mortars. The use of the blend of FA and POA also produces high strength mortars and excellent resistance to chloride penetration owing to the synergic effect of FA and POA. A mathematical analysis and two-parameter polynomial model were presented to predict the compressive strength. The mathematical model correlated well with the experimental results. The computer 3-D graphics of strength of the ternary blended mortars were also constructed and could be used to aid the understanding and the proportioning of the blended system.
文摘Creating a sustainable energy and environment, alternative energy is needed to be developed instead of using fossil fuels. This research describe a comparison of the use of pyrolysis oils which are the tire pyrolysis oil, plastic pyrolysis oil and diesel oil in the assessment of engine performance, and feasibility analysis. Pyrolysis oils from waste tire and waste plastic are studied to apply with one cylinder multipurpose agriculture diesel engine. It is found that without engine modification, the tire pyrolysis offers better engine performance whereas the heating value of the plastic pyrolysis oil is higher. The plastic pyrolysis oil could improve performance by modifying engine. The economic analysis shows that the pyrolysis oil is able to replace diesel in terms of engine performance and energy output if the price of pyrolysis oil is not greater than 85% of diesel oil.
基金financially supported by the Office of the National Research Council of Thailand (NRCT)Higher Education Research Promotion and National Research University Project of Thailand+2 种基金Office of the Higher Education Commission,through the Advanced Functional Materials Cluster of Khon Kaen Universitythe Thailand Research Fund (TRF) under the TRF Senior Research Scholar Contract No. RTA5480004Rajamangala University of Technology Phra Nakhon (RMUTP)
文摘This article presents a study on the resistance to chloride penetration, corrosion, porosity, and strength of mortar containing fine fly ash （FA）, ground rice husk-bark ash （RB）, and ground bagasse ash （BA）. Ordinary Portland cement （CT） was blended with a single pozzolan and two pozzolans. Strength, porosity, rapid chloride penetration, immersion, and corrosion tests were performed to characterize the mortar. Test results showed that the use of ternary blends of CT, FA, and RB or BA decreased the porosity of the mortar, as compared with binary blended mortar containing CT and RB or BA. The resistance to chloride penetration of the mortar improved substantially with partial replacement of CT with FA, RB, and BA. The use of ternary blends of CT, FA and RB or BA produced the mortar with good strength and resistance to chloride penetration. The resistance to chloride penetration was higher with an increase in the replacement level due to the reduced calcium hydroxide.
文摘A <st1:data language="0" startpos="3" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">distributed generator is <st1:data language="0" startpos="28" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">a small-scaled <st1:data language="0" startpos="42" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">active <st1:data language="0" startpos="49" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">generating <st1:data language="0" startpos="60" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">unit <st1:data language="0" startpos="65" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in the system power loss if their locations and sizes are appropriately determined. For this reason, the main objective of this paper is to develop mathematical models and a technique based on tabu search for the optimal placement and sizing of DGs in a distribution system. Numerical results from tests on 12-, 33- and 13-bus distribution systems with different load distributions show that the system power loss with DGs can be significantly reduced when compared with that without the DGs. " w:st="on">located <st1:data language="0" startpos="73" context="A distributed generator is a small-scale active generating unit located on or near the site where it is to be used. Several benefits have been realized by installing DGs in the distribution network. Among them is a reduction in
文摘This paper analyzes the effects of the voltage across insulator of 69 kV and 24 kV lines installed on the same pole. The case studies illustrated the lightning strike to direct top pole and mid span of ground wire using the ATP-EMTP （Alternative Transient Program-Electromagnetic Transient Program）. The results found that when lightning strike the voltage across the 69 kV line insulator at mid span is 1.55 times and 1.34 times higher than at top pole when the front time is 0.25/100μs and 10/350 μs, respectively. When lightning strike the voltage across the 24 kV line at mid span is 1.04 times and 0.64 times higher than at top pole when the front time is 0.25/100μs and 10/350μs, respectively. So the effect of lightning strike is more severe at mid span than at the direct top pole, especially for the 69 kV insulator.
文摘ELD （economic load dispatch） problem is one of the essential issues in power system operation. The objective of solving ELD problem is to allocate the generation output of the committed generating units. The main contribution of this work is to solve the ELD problem concerned with daily load pattern. The proposed solution technique, developed based PSO （particle swarm optimization） algorithm, is applied to search for the optimal schedule of all generations units that can supply the required load demand at minimum fuel cost while satisfying all unit and system operational constraints. The performance of the developed methodology is demonstrated by case studies in test system of six-generation units. The results obtained from the PSO are compared to those achieved from other approaches, such as QP （quadratic programming）, and GA （genetic algorithm）.
文摘This paper presents an efficient algorithm for optimization of radial distribution systems by a network reconfiguration to balance feeder loads and eliminate overload conditions. The system load-balancing index is used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal network reconfiguration of load balancing. The tabu search algorithm is employed to search for the optimal network reconfiguration. The basic idea behind the search is a move from a current solution to its neighborhood by effectively utilizing a memory to provide an efficient search for optimality. It presents low computational effort and is able to find good quality configurations. Simulation results for a radial 69-bus system. The study results show that the optimal on/off patterns of the switches can be identified to give the best network reconfiguration involving balancing of feeder loads while respecting all the constraints.
