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Many researches showed that urbanization results in groundwater pollution, and NO_3 -N pollution is the obviousest. For example, the centres of groundwater pollution in big and medium-sized cities in China such as Beijing, Shenyan...
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Many researches showed that urbanization results in groundwater pollution, and NO_3 -N pollution is the obviousest. For example, the centres of groundwater pollution in big and medium-sized cities in China such as Beijing, Shenyang, Xian and Shangqiu etc. all tie in the old urban area, and pollution lowers toward outskirts of each city. NO_3 -N pollution of ground water is often found in some old residential areas or residential ruins in wide countryside. For example, NO_3 -N content in the groundwater in a well near a bigger residential ruins in Tuanbei village of Gaoling county of Shanxi province is high up to 100 ppm. The above-mentioned situation has been found in the other countries. For example, in Nigeria[1], average content of NO_3-N in the ground water where no residents live is only 0.56-1.74 ppm, and that is high up to 12-34.8 ppm in well water near towns and residential areas of countrysides.
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The road sign is an important facility which manages the road traffic safety and eases the road traffic congestion. This paper proposes a Semantically-enabled System for Road Sign Management (SeRSM). The SeRSM system is built base...
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The road sign is an important facility which manages the road traffic safety and eases the road traffic congestion. This paper proposes a Semantically-enabled System for Road Sign Management (SeRSM). The SeRSM system is built based on LarKC, which is a platform for scalable semantic data processing. In the SeRSM system, the users can select the corresponding operations through the interface integrated with a map service. These operations are sent to Jetty server for corresponding processing. They include sending some SPARQL query to invoke the corresponding workflow in the LarKC platform and to retrieve and reason the massive data stored in the data layer of LarKC and to return the result to the Jetty server. The paper made a full description of technical points such as the design objective, data sources, data integration, noisy data processing, detection of road consistency effectiveness. It also describes the system's user interface and basic functions in the end. The SeRSM has great value and social significance for improving traffic efficiency and traffic safety through successful applications in Zhenjiang and Yiwu in China.
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摘要 :
The road sign is an important facility which manages the road traffic safety and eases the road traffic congestion. This paper proposes a Semantically-enabled System for Road Sign Management (SeRSM). The SeRSM system is built base...
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The road sign is an important facility which manages the road traffic safety and eases the road traffic congestion. This paper proposes a Semantically-enabled System for Road Sign Management (SeRSM). The SeRSM system is built based on LarKC, which is a platform for scalable semantic data processing. In the SeRSM system, the users can select the corresponding operations through the interface integrated with a map service. These operations are sent to Jetty server for corresponding processing. They include sending some SPARQL query to invoke the corresponding workflow in the LarKC platform and to retrieve and reason the massive data stored in the data layer of LarKC and to return the result to the Jetty server. The paper made a full description of technical points such as the design objective, data sources, data integration, noisy data processing, detection of road consistency effectiveness. It also describes the system's user interface and basic functions in the end. The SeRSM has great value and social significance for improving traffic efficiency and traffic safety through successful applications in Zhenjiang and Yiwu in China.
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摘要 :
The road sign is an important facility which manages the road traffic safety and eases the road traffic congestion. This paper proposes a Semantically-enabled System for Road Sign Management (SeRSM). The SeRSM system is built base...
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The road sign is an important facility which manages the road traffic safety and eases the road traffic congestion. This paper proposes a Semantically-enabled System for Road Sign Management (SeRSM). The SeRSM system is built based on LarKC, which is a platform for scalable semantic data processing. In the SeRSM system, the users can select the corresponding operations through the interface integrated with a map service. These operations are sent to Jetty server for corresponding processing. They include sending some SPARQL query to invoke the corresponding workflow in the LarKC platform and to retrieve and reason the massive data stored in the data layer of LarKC and to return the result to the Jetty server. The paper made a full description of technical points such as the design objective, data sources, data integration, noisy data processing, detection of road consistency effectiveness. It also describes the system's user interface and basic functions in the end. The SeRSM has great value and social significance for improving traffic efficiency and traffic safety through successful applications in Zhenjiang and Yiwu in China.
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In this paper, the concept of "computing checkpoint" is introduced, and then an efficient coordinated checkpoint algorithm is proposed. The algorithm combines the two approaches of reducing the overhead associated with coordinated...
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In this paper, the concept of "computing checkpoint" is introduced, and then an efficient coordinated checkpoint algorithm is proposed. The algorithm combines the two approaches of reducing the overhead associated with coordinated checkpointing, which one is to minimize the processes which take checkpoints and the other is to make the checkpointing process non-blocking. Through piggybacking the information including which processes have taken new checkpoint in the broadcast committing message, the checkpoint sequence number of every process can be kept consistent in all processes, so that the unnecessary checkpoints and orphan messages can be avoided in the future running. Evaluation result shows that the number of redundant computing checkpoints is less than 1/10 of the number of tentative checkpoints. Analyses and experiments show that the overhead of our algorithm is lower than that of other coordinated checkpoint algorithms.
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In this paper, the concept of “computing checkpoint” is introduced, and then an efficient coordinated checkpoint algorithm is proposed. The algorithm combines the two approaches of reducing the overhead associated with coordinat...
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In this paper, the concept of “computing checkpoint” is introduced, and then an efficient coordinated checkpoint algorithm is proposed. The algorithm combines the two approaches of reducing the overhead associated with coordinated checkpointing, which one is to minimize the processes which take checkpoints and the other is to make the checkpointing process non-blocking. Through piggybacking the information including which processes have taken new checkpoint in the broadcast committing message, the checkpoint sequence number of every process can be kept consistent in all processes, so that the unnecessary checkpoints and orphan messages can be avoided in the future running. Evaluation result shows that the number of redundant computing checkpoints is less than 1/10 of the number of tentative checkpoints. Analyses and experiments show that the overhead of our algorithm is lower than that of other coordinated checkpoint algorithms.
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The fractal dimensions in difierent topological spaces of polyferric chloride-humic acid (PFC-HA)flocs,formed in flocculated different kinds of HA water with the initial pH values(9.0,7.0,5.0)at optimum PFC dosages,were calculated...
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The fractal dimensions in difierent topological spaces of polyferric chloride-humic acid (PFC-HA)flocs,formed in flocculated different kinds of HA water with the initial pH values(9.0,7.0,5.0)at optimum PFC dosages,were calculated by effective density-maximum diameter.image analysis and N,absorption-desorption methods,respectivley.The mass fractal dimensions Df of PFC-HA flocs,being less than 2.0,calculated by bi-logarithm relation of effective density.maximum diameter and Logan equation at initial pH of 7.0 was little greater than that at initial pH of 9.0.but had 11.73％greater than that initial pH Of 5.0.The image analysis for those flocs indicates that after flocculating the HA water at initial pH greater than 7.0 with PFC flocculant,the fractal dimensions of D2(IgA-lgdL)and D3(1gVphere-lgdL)of PFC-HA flocs decreased with the increase of PFC dosages.and PFC-HA flocs showed a gradually looser structure.However,the fractal dimensions of PFC-HA flocs in flocculated water at initial pH of 5.0 fluctuated with PFC addition.Based on fractal FHH adsorption and desorption equations.the pore surface fractal dimensions Ds for dried powders of samplel(initial pH=9.0)and sample2(initial pH=7.0)were all close to 2.94,but Ds values of sample3(initial pH=5.0)were less than 2.38.
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A finite element model of temperature field for plasma spraying preset MCrAlY coating during laser cladding was constructed using ANSYS parametric design language (APDL) in accordance to characteristics of preset laser cladding. I...
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A finite element model of temperature field for plasma spraying preset MCrAlY coating during laser cladding was constructed using ANSYS parametric design language (APDL) in accordance to characteristics of preset laser cladding. Influencing laws of laser cladding parameters on temperature field were analyzed. Results show that laser power influences temperature field of cladding samples more than laser scanning speed. Experimental results agree well with simulation results, which prove the accuracy and reliability of the constructed calculation model of temperature field. Heating and cooling laws in the laser cladding process could be mastered through this calculation model. Research conclusions provide some references to optimization parameters in preparing high-performance laser cladding coatings.
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A finite element model of thermal coupling stress field during laser cladding plasma spraying of preset MCrAlY coating was constructed based on the finite element model of temperature field by using the indirect thermal coupling m...
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A finite element model of thermal coupling stress field during laser cladding plasma spraying of preset MCrAlY coating was constructed based on the finite element model of temperature field by using the indirect thermal coupling method in ANSYS finite element software. Moreover, stress field during laser cladding was analyzed. Through the constructed model, variation laws of stress field with time during laser cladding and cooling process could be mastered. Based on the stress field, the formation mechanism of cracks in laser cladding coating and influencing factors were further analyzed and some solutions to cracks of laser cladding coating were proposed.
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In order to solve the problem of system resilience recovery, a greedy model that considered the importance of system nodes' tasks, arrival time, and maintenance time has been proposed, this paper used optimal solutions produced by...
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In order to solve the problem of system resilience recovery, a greedy model that considered the importance of system nodes' tasks, arrival time, and maintenance time has been proposed, this paper used optimal solutions produced by greedy algorithm as the initial population of the genetic algorithm, which can avoid premature in algorithm. Moreover, in view of the characteristics of multi-chromosome coding, this paper used inter-group crossover operator, inter-group flipping operator, inter-group sliding operator and random grouping operator with limited length to update population, increasing the diversity of variation and feasible solutions. The simulation compared the improved initial population and multi-mutation genetic algorithm proposed in this paper with the basic genetic algorithm and the improved initial population genetic algorithm. Experimental results demonstrate that the way of improving initial population of genetic algorithm can effectively improve the feasible solution and convergence of the algorithm, and combining it with four evolutionary operators can further optimize the feasible solution of the algorithm. And more, the improved initial population and multiple mutation genetic algorithm has better stability in solving the system resilience recovery problem.
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