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Cloud storage is an active research domain currently, and how to secure the reliability of data is an important research issue. For the moment, most systems apply the static data replication strategy, which causes a serious waste of storage resources. Considering the user requirements and the factors influenced on data reliability, i.e., the node reliability and Relevant Failure Degree, Data Replication Strategy based on Relevant Failure is provided in this paper. According to the results of the experiments, our strategy reduces the number of data replicas and meets the user requirement of reliability at the same time. Besides, the strategy has a better performance on increasing the utilization of storage resources.

The potential of using the waste from simultaneous NOx and SO2 purification bio-trickling process to leach copper ore and to make fertilizer was investigated. It was found there were two main exhausted by-products in the purification process: the acidic liquid in desulfurization tower and the alkalescent liquid in denitrogenation tower. Through operation of leaching the oxide ore sample containing 2.58% copper by the acidic liquid, the effective grade of the metal to be extracted reached 28.37% by weight. With adding proportional dose of ammonia into the alkalescent liquid or the acidic liquid and going through evaporation and concentration, crystal products of ammonium sulfate and ammonium nitrate were generated, which can be used in fertilizer manufacturing.

The kinematics and dynamic analysis of the large-displacement motion simulator is analyzed and derived in detail. By using MATLAB program, the simulation curves of the derived kinematics and dynamic formula match to the practical situation. Our result will provide the theoretical direction for the further study of the large-displacement motion simulator.

The large-displacement motion simulator which composed by Cartesian coordinate movement Desk and Three-axis turntable was designed in this paper. This Motion simulator can move the working spaces to any position of the space by any posture, which solved the disadvantages of the STEWART platform, the smaller spatial displacement and limited space corner. Kinematic analysis of the large-displacement motion simulator was discussed in this article, and theoretical modeling of the large-displacement motion simulator was presented by KANE equations. This has the theoretical significance for the research of the technology of space motion simulation and docking.

The degree of flexibility of workflow management systems heavily influences the way business processes are executed. Constraint-based models are considered to be more flexible than traditional models because of their semantics: everything that does not violate constraints is allowed. More and more people use declarative languages to define workflow, such as linear temporal logic. But how to guarantee the correctness of the model based on the linear temporal logic is still a problem. This article proposes a way to verify the model based on Büchi automaton and gives the corresponding algorithms. Thus the verification of declarative workflow based on the linear temporal logic is solved.

To realize the efficient and stable real-time monitoring and intelligent management of the urban public lighting, the remote monitoring system is developed. The system is composed of monitoring center and monitoring terminals, and realizes network connection via the advanced remote wireless communication technology GPRS. It uses TI Company’s MSP430 processor chip as the monitoring terminal controller, which integrates automatic control, data acquisition, communication and other technologies and has such functions as monitoring, remote control, anti-electricity theft, remote meter reading and communication. It’s proved by practice that the designed controller features reliable running, sound real-time performance and low cost, and has a broad and bright application prospect. The monitoring and management of public lighting is a typical sector and important part of the civil work. Due to the continuous development of urban construction and ever-enlarging lighting coverage, the traditional lighting management methods can not realize centralized monitoring, have poor real-time performance and cost lots of human and material resources; thus, can not satisfy the requirements of energy saving and efficiency improvement[1]. GPRS (General Packet Radio Service), the wireless packet exchange technology based on the second generation mobile communication system GSM, is very suitable for transmitting non-continuous, unexpected and small sets of street lamp monitoring data. Also, quick & easy log-on, real-time online, high-speed transmission, sound economical efficiency and many other advantages make GPRS become the first choice for remote measurement and control system[2]. Therefore, the development of GPRS-based public lighting remote monitoring system becomes a necessity. The designed monitoring system in this article is a typical distributed monitoring and data acquisition system integrating computer technologies, modern communication technologies and automatic control technologies. It conducts centralized monitoring and control on the cabinet transformer substations, transformer cabinets, control cabinets and other slave monitoring systems of the public lighting such as street lamps and landscape lamps of the city, to realize the real-time, remote monitoring and intelligent management of public lighting and ensure the efficient, all-weather running and on-demand, energy-saving lighting.