In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasib...In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it.展开更多
Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and th...Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining.展开更多
Software Defined Networking(SDN) provides flexible network management by decoupling control plane from data plane. And multiple controllers are deployed to improve the scalability and reliability of the control plane,...Software Defined Networking(SDN) provides flexible network management by decoupling control plane from data plane. And multiple controllers are deployed to improve the scalability and reliability of the control plane, which could divide the network into several subdomains with separate controllers. However, such deployment introduces a new problem of controller load imbalance due to the dynamic traffic and the static configuration between switches and controllers. To address this issue, this paper proposes a Distribution Decision Mechanism(DDM) based on switch migration in the multiple subdomains SDN network. Firstly, through collecting network information, it constructs distributed migration decision fields based on the controller load condition. Then we choose the migrating switches according to the selection probability, and the target controllers are determined by integrating three network costs, including data collection, switch migration and controller state synchronization. Finally, we set the migrating countdown to achieve the ordered switch migration. Through verifying several evaluation indexes, results show that the proposed mechanism can achieve controller load balancing with better performance.展开更多
Through Pickering's and extended Painleve nonstandard truncated expansionmethod, this paper solves the phase-separating dynamics equation of diblock copolymer, and obtainsvarious exact solutions. We discuss non-co...Through Pickering's and extended Painleve nonstandard truncated expansionmethod, this paper solves the phase-separating dynamics equation of diblock copolymer, and obtainsvarious exact solutions. We discuss non-complex special solutions which can be made up of hyperbolicfunctions or elliptic functions.展开更多
A numerical study based on the finite volume method has been performed to study the three-dimension natural convection in a parallelogrammic top side opened cavity filled nanofluid with partially heated square at the ...A numerical study based on the finite volume method has been performed to study the three-dimension natural convection in a parallelogrammic top side opened cavity filled nanofluid with partially heated square at the bottom side.Results are obtained for different governing parameters such as nanoparticle concentration (φ) from 0 to 0.05,inclination angle of the back and front walls (α) from 5° to 75°,Rayleigh number from 10^3 to 10^5,and length of heater changer from 0.1 to 1.The main finding from the obtained result showed that the inclination angle and nanoparticle volume fraction affect the flow structure and enhance the heat transfer.展开更多
Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processin...Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processing. Such system can help accelerate research and development of future wireless network, especially in the case of cellular/Wi-Fi co-existing networks. This platform is based on the Intel general-purpose processor and the universal software radio peripheral(USRP) radio front end. The design including the physical layer implementations is purely software and is optimized for real-time signal processing on the general purpose processor. In the lab experiment, this platform supports baseband rate up to 700 Mbps with 2 transmitters in 80 MHz bandwidth. A cellular-Wi-Fi signaling interface between the Wi-Fi access point(AP) and the 5G core network is also developed and validated as an example for wireless resource allocation.展开更多
This paper presents an innovative switched-mode auto gain control （AGC） circuit with internally created reset module for DC-10Mb/s burst-mode unbalanced （BMU） optical data transmission. Conventional AGC circuit is...This paper presents an innovative switched-mode auto gain control （AGC） circuit with internally created reset module for DC-10Mb/s burst-mode unbalanced （BMU） optical data transmission. Conventional AGC circuit is inappropriate for BMU data transmission because it is based on average level detection and requires considerable time to settle on a predefined gain. Therefore, we adopt a fast switched-mode AGC based on peak level detection. After the gain is adjusted, the peak level detectors need to re-detect the peak level of the input signal. Thus, we develop an internally created reset module. This AGC with reset module exhibits a fast operation and achieves an adjusted stable gain within one-bit, avoiding any bit loss up to 10Mb/s data rate. During power-up, the peak level detectors possibly hold an uncertain level resulting in the bit-errors. We propose a power-up reset circuit to solve this problem. Designed in a 0.5μm CMOS technology, the circuit achieves an optical sensitivity of better than -30dBm and a wide dynamic range of over 30dB with a power dissipation of only 30 mW from a 5V supply.展开更多
Ocean information management is of great importance as it has been employed in many areas of ocean science and technology. However, the developments of Ocean Information Systems(OISs) often suffer from low efficiency ...Ocean information management is of great importance as it has been employed in many areas of ocean science and technology. However, the developments of Ocean Information Systems(OISs) often suffer from low efficiency because of repetitive work and continuous modifications caused by dynamic requirements. In this paper, the basic requirements of OISs are analyzed first, and then a novel platform DPOI is proposed to improve development efficiency and enhance software quality of OISs by providing off-the-shelf resources. In the platform, the OIS is decomposed hierarchically into a set of modules, which can be reused in different system developments. These modules include the acquisition middleware and data loader that collect data from instruments and files respectively, the database that stores data consistently, the components that support fast application generation, the web services that make the data from distributed sources syntactical by use of predefined schemas and the configuration toolkit that enables software customization. With the assistance of the development platform, the software development needs no programming and the development procedure is thus accelerated greatly. We have applied the development platform in practical developments and evaluated its efficiency in several development practices and different development approaches. The results show that DPOI significantly improves development efficiency and software quality.展开更多
The effect of terminal groups on the electron transport through metal-molecule-metal system has been investigated using nonequilibrium Green's function (NEGF) formalism combined with extended Huckel theory (EHT). ...The effect of terminal groups on the electron transport through metal-molecule-metal system has been investigated using nonequilibrium Green's function (NEGF) formalism combined with extended Huckel theory (EHT). Au-molecule-Au junctions are constructed with borazine and BCN unit structure as core molecule and sulphur (S), oxygen (O), selenium (Se) and cyano-group (CN) as terminal groups. The electron transport characteristics of the borazine and BCN molecular systems are analyzed through the transmission spectra and the current-voltage curve. The results demonstrate that the terminal groups modifying the transport behaviors of these systems in a controlled way. Our result shows that, selenium is the best linker to couple borazine to Au electrode and oxygen is the best one to couple BCN to Au electrode. Furthermore, the results of borazine systems are compared with that of BCN molecular systems and are discussed. Simulation results show that the conductance through BCN molecular systems is four times larger than the borazine molecular systems. Negative differential resistance behavior is observed with borazine-CN system and the saturation feature appears in BCN systems.展开更多
文摘In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it.
基金Project(10872218) supported by the National Natural Science Foundation of ChinaProject(2010CB732004) supported by the National Key Basic Research Program of China+1 种基金Project(20090461022) supported by the National Postdoctoral Foundation of ChinaProject (11MX21) supported by the Students' Innovation Project Aubsidize Award of Arcelor Mittal
文摘Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining.
基金supported in part by This work is supported by the Project of National Network Cyberspace Security(Grant No.2017YFB0803204)the National High-Tech Research and Development Program of China(863 Program)(Grant No.2015AA016102)+1 种基金Foundation for Innovative Research Group of the National Natural Science Foundation of China(Grant No.61521003)Foundation for the National Natural Science Foundation of China(Grant No.61502530)
文摘Software Defined Networking(SDN) provides flexible network management by decoupling control plane from data plane. And multiple controllers are deployed to improve the scalability and reliability of the control plane, which could divide the network into several subdomains with separate controllers. However, such deployment introduces a new problem of controller load imbalance due to the dynamic traffic and the static configuration between switches and controllers. To address this issue, this paper proposes a Distribution Decision Mechanism(DDM) based on switch migration in the multiple subdomains SDN network. Firstly, through collecting network information, it constructs distributed migration decision fields based on the controller load condition. Then we choose the migrating switches according to the selection probability, and the target controllers are determined by integrating three network costs, including data collection, switch migration and controller state synchronization. Finally, we set the migrating countdown to achieve the ordered switch migration. Through verifying several evaluation indexes, results show that the proposed mechanism can achieve controller load balancing with better performance.
文摘Through Pickering's and extended Painleve nonstandard truncated expansionmethod, this paper solves the phase-separating dynamics equation of diblock copolymer, and obtainsvarious exact solutions. We discuss non-complex special solutions which can be made up of hyperbolicfunctions or elliptic functions.
文摘A numerical study based on the finite volume method has been performed to study the three-dimension natural convection in a parallelogrammic top side opened cavity filled nanofluid with partially heated square at the bottom side.Results are obtained for different governing parameters such as nanoparticle concentration (φ) from 0 to 0.05,inclination angle of the back and front walls (α) from 5° to 75°,Rayleigh number from 10^3 to 10^5,and length of heater changer from 0.1 to 1.The main finding from the obtained result showed that the inclination angle and nanoparticle volume fraction affect the flow structure and enhance the heat transfer.
基金supported in part by the National Natural Science Foundation of China under Grant No. 61671436the Science and Technology Commission Foundation of Shanghai under Grant No. 15511102602, 16511104204
文摘Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processing. Such system can help accelerate research and development of future wireless network, especially in the case of cellular/Wi-Fi co-existing networks. This platform is based on the Intel general-purpose processor and the universal software radio peripheral(USRP) radio front end. The design including the physical layer implementations is purely software and is optimized for real-time signal processing on the general purpose processor. In the lab experiment, this platform supports baseband rate up to 700 Mbps with 2 transmitters in 80 MHz bandwidth. A cellular-Wi-Fi signaling interface between the Wi-Fi access point(AP) and the 5G core network is also developed and validated as an example for wireless resource allocation.
基金Supported by the Natural Science Foundation of Jiangsu Province （ BK2010411 ） and the National International Cooperation Project of China-Korea （2011DFA11310）.
文摘This paper presents an innovative switched-mode auto gain control （AGC） circuit with internally created reset module for DC-10Mb/s burst-mode unbalanced （BMU） optical data transmission. Conventional AGC circuit is inappropriate for BMU data transmission because it is based on average level detection and requires considerable time to settle on a predefined gain. Therefore, we adopt a fast switched-mode AGC based on peak level detection. After the gain is adjusted, the peak level detectors need to re-detect the peak level of the input signal. Thus, we develop an internally created reset module. This AGC with reset module exhibits a fast operation and achieves an adjusted stable gain within one-bit, avoiding any bit loss up to 10Mb/s data rate. During power-up, the peak level detectors possibly hold an uncertain level resulting in the bit-errors. We propose a power-up reset circuit to solve this problem. Designed in a 0.5μm CMOS technology, the circuit achieves an optical sensitivity of better than -30dBm and a wide dynamic range of over 30dB with a power dissipation of only 30 mW from a 5V supply.
基金supported in part by National Natural Science Foundation of China under grant No. 61170258 and 61379127National Ocean Public Benefit Research Foundation under grant No. 201305033-6 and 2011 05034-10+1 种基金Marine Renewable Energy Special Foundation under grant No. GHME2012ZC02Science and Technology Development Plan of Qingdao City under Grant No. 12-1-3-81-jh
文摘Ocean information management is of great importance as it has been employed in many areas of ocean science and technology. However, the developments of Ocean Information Systems(OISs) often suffer from low efficiency because of repetitive work and continuous modifications caused by dynamic requirements. In this paper, the basic requirements of OISs are analyzed first, and then a novel platform DPOI is proposed to improve development efficiency and enhance software quality of OISs by providing off-the-shelf resources. In the platform, the OIS is decomposed hierarchically into a set of modules, which can be reused in different system developments. These modules include the acquisition middleware and data loader that collect data from instruments and files respectively, the database that stores data consistently, the components that support fast application generation, the web services that make the data from distributed sources syntactical by use of predefined schemas and the configuration toolkit that enables software customization. With the assistance of the development platform, the software development needs no programming and the development procedure is thus accelerated greatly. We have applied the development platform in practical developments and evaluated its efficiency in several development practices and different development approaches. The results show that DPOI significantly improves development efficiency and software quality.
基金Supported by DST-FIST Project.financial support from DST-FIST, Government of India
文摘The effect of terminal groups on the electron transport through metal-molecule-metal system has been investigated using nonequilibrium Green's function (NEGF) formalism combined with extended Huckel theory (EHT). Au-molecule-Au junctions are constructed with borazine and BCN unit structure as core molecule and sulphur (S), oxygen (O), selenium (Se) and cyano-group (CN) as terminal groups. The electron transport characteristics of the borazine and BCN molecular systems are analyzed through the transmission spectra and the current-voltage curve. The results demonstrate that the terminal groups modifying the transport behaviors of these systems in a controlled way. Our result shows that, selenium is the best linker to couple borazine to Au electrode and oxygen is the best one to couple BCN to Au electrode. Furthermore, the results of borazine systems are compared with that of BCN molecular systems and are discussed. Simulation results show that the conductance through BCN molecular systems is four times larger than the borazine molecular systems. Negative differential resistance behavior is observed with borazine-CN system and the saturation feature appears in BCN systems.
