With the expansion of mountainous cities,many gully areas have been included in the scope of urban construction land.These gully areas will restrict urban construction because of sensitivity and instability caused by ...With the expansion of mountainous cities,many gully areas have been included in the scope of urban construction land.These gully areas will restrict urban construction because of sensitivity and instability caused by the unique ecological processes.This paper attempts to explore a planning and design strategy that combines ecological processes to reduce the risk of urban construction in gully areas.According to the ecological characteristics of gully areas,especially its suitability for urban construction,gully areas can be divided into three categories in the mountainous city:prevention and controlling gully—focusing on gully drainage;conservation gully—focusing on the construction of green space;utilization type gully—focusing on the development of gully towns.The utilization type gully can be used as urban construction land.For utilization type gullies,horizontal and vertical segmented planning strategies can adopt their respective ecological processes by land utilization,landscape construction,spatial layout and traffic organization matching the time-space natural process to form harmony human settlements.展开更多
Logic qubit plays an important role in current quantum communication. In this paper, we propose an efficient entanglement concentration protocol (ECP) for a new kind of logic Bell state, where the logic qubit is the c...Logic qubit plays an important role in current quantum communication. In this paper, we propose an efficient entanglement concentration protocol (ECP) for a new kind of logic Bell state, where the logic qubit is the concatenated Greenber- Horne- Zeilinger (C-GHZ) state. Our ECP relies on the nondemolition polarization parity check (PPC) gates constructed with cross-Kerr nonlinearity, and can distill one pair of maximally entangled logic Bell state from two same pairs of less-entangled logic Bell states. Benefit from the nondemolition PPC gates, the concentrated maximally entangled logic Bell st ate can be remained for further application. Moreover, our ECP can be rcpea ted to further concentrate the less-entangled logic Bell state. By repeating the ECP. the total success probability can be effectively increased. Based on above features, this ECP may be useful in future long-distance quantum communication.展开更多
基金supported by National Key R&D Program of China“Optimization Technology for Urban New District Planning and Design(Grant No.2018YFC0704600)”
文摘With the expansion of mountainous cities,many gully areas have been included in the scope of urban construction land.These gully areas will restrict urban construction because of sensitivity and instability caused by the unique ecological processes.This paper attempts to explore a planning and design strategy that combines ecological processes to reduce the risk of urban construction in gully areas.According to the ecological characteristics of gully areas,especially its suitability for urban construction,gully areas can be divided into three categories in the mountainous city:prevention and controlling gully—focusing on gully drainage;conservation gully—focusing on the construction of green space;utilization type gully—focusing on the development of gully towns.The utilization type gully can be used as urban construction land.For utilization type gullies,horizontal and vertical segmented planning strategies can adopt their respective ecological processes by land utilization,landscape construction,spatial layout and traffic organization matching the time-space natural process to form harmony human settlements.
基金the National Natural Science Foundation of China under Grant Nos. 11474168 and 11747161.
文摘Logic qubit plays an important role in current quantum communication. In this paper, we propose an efficient entanglement concentration protocol (ECP) for a new kind of logic Bell state, where the logic qubit is the concatenated Greenber- Horne- Zeilinger (C-GHZ) state. Our ECP relies on the nondemolition polarization parity check (PPC) gates constructed with cross-Kerr nonlinearity, and can distill one pair of maximally entangled logic Bell state from two same pairs of less-entangled logic Bell states. Benefit from the nondemolition PPC gates, the concentrated maximally entangled logic Bell st ate can be remained for further application. Moreover, our ECP can be rcpea ted to further concentrate the less-entangled logic Bell state. By repeating the ECP. the total success probability can be effectively increased. Based on above features, this ECP may be useful in future long-distance quantum communication.
