In order to search for reasonable air conditioned indoor control variables and save energy consumption and meet to need of personal thermal comfort, a method which is based on numerical simulation is employed to optim...In order to search for reasonable air conditioned indoor control variables and save energy consumption and meet to need of personal thermal comfort, a method which is based on numerical simulation is employed to optimize indoor control variables. Computational fluid dynamics （CFD） is used to describe thermal state of office. An optimal method is proposed in this paper, dual neural network model is firstly used to acquire reliable information, data from CFD model are pre pro cessed, and the remaining data are used to train artificial neural networks （ANN）, then CFD model is replaced by ANN model to reduce computational cost when is optimized, indoor control variables are optimized by genetic algorithm. Simulation results show that indoor thermal comfort is improved obviously, and the energy cost is decreased accordingly.展开更多
A novel deterministic packet marking （DPM） for IP traceback against denial of service （DOS） and distributed denial of service （DDoS） attacks is presented, which features good scalability and high accuracy. In th...A novel deterministic packet marking （DPM） for IP traceback against denial of service （DOS） and distributed denial of service （DDoS） attacks is presented, which features good scalability and high accuracy. In this scheme, an ingress router pre-calculates a Hash of its IP address and splits the Hash into several fragments. When marking a packet, the router randomly selects a fragment to mark into the packet. In the traceback stage the victim identifies the marked router with the help of the map of its upstream routers. Based on the map, the victim can identify a candidate ingress router after receiving only several marked packets. The scheme overcomes defects in previous deterministic packet marking schemes, where too much packets are required to recover a router and high false positive rate occurs in case of large-scale DDoS. Theoretical analysis, the pseudo code and experimental results are provided. The scheme is proved to be accurate and efficient and can handle large-scale DDoS attacks.展开更多
基金Supported by Basic Research Foundation of Beijing Institute of Technology(20070542009)
文摘In order to search for reasonable air conditioned indoor control variables and save energy consumption and meet to need of personal thermal comfort, a method which is based on numerical simulation is employed to optimize indoor control variables. Computational fluid dynamics （CFD） is used to describe thermal state of office. An optimal method is proposed in this paper, dual neural network model is firstly used to acquire reliable information, data from CFD model are pre pro cessed, and the remaining data are used to train artificial neural networks （ANN）, then CFD model is replaced by ANN model to reduce computational cost when is optimized, indoor control variables are optimized by genetic algorithm. Simulation results show that indoor thermal comfort is improved obviously, and the energy cost is decreased accordingly.
基金supported by the Hi-Tech Research and Development Program of China (2009AA01Z433)
文摘A novel deterministic packet marking （DPM） for IP traceback against denial of service （DOS） and distributed denial of service （DDoS） attacks is presented, which features good scalability and high accuracy. In this scheme, an ingress router pre-calculates a Hash of its IP address and splits the Hash into several fragments. When marking a packet, the router randomly selects a fragment to mark into the packet. In the traceback stage the victim identifies the marked router with the help of the map of its upstream routers. Based on the map, the victim can identify a candidate ingress router after receiving only several marked packets. The scheme overcomes defects in previous deterministic packet marking schemes, where too much packets are required to recover a router and high false positive rate occurs in case of large-scale DDoS. Theoretical analysis, the pseudo code and experimental results are provided. The scheme is proved to be accurate and efficient and can handle large-scale DDoS attacks.
