P This paper studies how phase synchronization in complex networks depends on random shortcuts, using the uous chaotic Chua system as the nodes of the networks. It is found that for a given coupling strength when the ...P This paper studies how phase synchronization in complex networks depends on random shortcuts, using the uous chaotic Chua system as the nodes of the networks. It is found that for a given coupling strength when the number of random shortcuts is greater than a threshold the phase synchronization is induced. Phase synchronization becomes evident and reaches its maximum as the number of random shortcuts is further increased. These phenomena imply that random shortcuts can induce and enhance the phase synchronization in complex Chua systems. Furthermore, the paper also investigates the effects of the coupling strength and it is found that stronger coupling makes it easier to obtain the complete phase synchronization.展开更多
As a key to improve the performance of the interbay automated material handling system （AMHS） in 300 mm semiconductor wafer fabrication system, the real- time overhead hoist transport （OHT） dispatching problem has...As a key to improve the performance of the interbay automated material handling system （AMHS） in 300 mm semiconductor wafer fabrication system, the real- time overhead hoist transport （OHT） dispatching problem has received much attention. This problem is first formu- lated as a special form of assignment problem and it is proved that more than one solution will be obtained by Hungarian algorithm simultaneously. Through proposing and strictly proving two propositions related to the char- acteristics of these solutions, a modified Hungarian algo- rithm is designed to distinguish these solutions. Finally, a new real-time OHT dispatching method is carefully designed by implementing the solution obtained by the modified Hungarian algorithm. The experimental results of discrete event simulations show that, compared with con- ventional Hungarian algorithm dispatching method, the proposed dispatching method that chooses the solution with the maximum variance respectively reduces on average 4 s of the average waiting time and average lead time of wafer lots, and its performance is rather stable in multiple dif- ferent scenarios of the interbay AMHS with different quantities of shortcuts. This research provides an efficient real-time OHT dispatching mechanism for the interbay AMHS with shortcuts and bypasses.展开更多
As one of the most promising candidates for implementing quantum computers, superconducting qubits（SQs） are adopted for fast generating the Greenberger–Horne–Zeilinger（GHZ） state by using invariants-based shortc...As one of the most promising candidates for implementing quantum computers, superconducting qubits（SQs） are adopted for fast generating the Greenberger–Horne–Zeilinger（GHZ） state by using invariants-based shortcuts. Three SQs are separated and connected by two coplanar waveguide resonators（CPWRs） capacitively. The complicated system is skillfully simplified to a three-state system, and a GHZ state among three SQs is fast generated with a very high fidelity and simple driving pulses. Numerical simulations indicate the scheme is insensitive to parameter deviations. Besides, the robustness of the scheme against decoherence is discussed in detail.展开更多
A P2P scientific collaboration is a P2P network whose members can share documents, co-compile papers and codes, and communicate with each other instantly. From the simulation experiment we found that P2P collaboration...A P2P scientific collaboration is a P2P network whose members can share documents, co-compile papers and codes, and communicate with each other instantly. From the simulation experiment we found that P2P collaboration system is a power-law network with a tail between -2 and -3.We utilized the algorithm that searches by high-degree shortcuts to improve the scalability of p2p collaboration system. The experimental result shows that the algorithm works better than random walk algorithm.展开更多
High-fidelity quantum gates are essential for large-scale quantum computation.However,any quantum manipulation will inevitably affected by noises,systematic errors and decoherence effects,which lead to infidelity of a...High-fidelity quantum gates are essential for large-scale quantum computation.However,any quantum manipulation will inevitably affected by noises,systematic errors and decoherence effects,which lead to infidelity of a target quantum task.Therefore,implementing high-fidelity,robust and fast quantum gates is highly desired.Here,we propose a fast and robust scheme to construct high-fidelity holonomic quantum gates for universal quantum computation based on resonant interaction of three-level quantum systems via shortcuts to adiabaticity.In our proposal,the target Hamiltonian to induce noncyclic non-Abelian geometric phases can be inversely engineered with less evolution time and demanding experimentally,leading to high-fidelity quantum gates in a simple setup.Besides,our scheme is readily realizable in physical system currently pursued for implementation of quantum computation.Therefore,our proposal represents a promising way towards fault-tolerant geometric quantum computation.展开更多
Quantum batteries are energy storage devices that satisfy quantum mechanical principles.How to improve the battery’s performance such as stored energy and power is a crucial element in the quantum battery.Here,we inv...Quantum batteries are energy storage devices that satisfy quantum mechanical principles.How to improve the battery’s performance such as stored energy and power is a crucial element in the quantum battery.Here,we investigate the charging and discharging dynamics of a three-level counterdiabatic stimulated Raman adiabatic passage quantum battery via shortcuts to adiabaticity,which can compensate for undesired transitions to realize a fast adiabatic evolution through the application of an additional control field to an initial Hamiltonian.The scheme can significantly speed up the charging and discharging processes of a three-level quantum battery and obtain more stored energy and higher power compared with the original stimulated Raman adiabatic passage.We explore the effect of both the amplitude and the delay time of driving fields on the performances of the quantum battery.Possible experimental implementation in superconducting circuit and nitrogen–vacancy center is also discussed.展开更多
We propose a scheme for a fast generating three-qubit W state in a superconducting system by using a technique of shortcuts to adiabaticity, Lewis–Riesenfeld invariants. Three identical superconducting qubits（SQs） ...We propose a scheme for a fast generating three-qubit W state in a superconducting system by using a technique of shortcuts to adiabaticity, Lewis–Riesenfeld invariants. Three identical superconducting qubits（SQs） are connected by two coplanar waveguide resonators（CPWRs） capacitively. Under a certain limit condition, we convert the complicated SQ system into a simple three-state system. By designing experimentally accessible harmonic pulses, a three-SQ W state is implemented with quite short operation time and high fidelity. Numerical simulations prove that the scheme is robust against the parameter deviation. In addition, we also give detailed discussion about the scheme robustness against decoherence.展开更多
Construction of optimal gate operations is significant for quantum computation.Here an efficient scheme is proposed for performing shortcut-based quantum gates on superconducting qubits in circuit quantum electrodynam...Construction of optimal gate operations is significant for quantum computation.Here an efficient scheme is proposed for performing shortcut-based quantum gates on superconducting qubits in circuit quantum electrodynamics(QED).Two four-level artificial atoms of Cooper-pair box circuits,having sufficient level anharmonicity,are placed in a common quantized field of circuit QED and are driven by individual classical microwaves.Without the effect of cross resonance,one-qubit NOT gate and phase gate in a decoupled atom can be implemented using the invariant-based shortcuts to adiabaticity.With the assistance of cavity bus,a one-step SWAP gate can be obtained within a composite qubit-photon-qubit system by inversely engineering the classical drivings.We further consider the gate realizations by adjusting the microwave fields.With the accessible decoherence rates,the shortcut-based gates have high fidelities.The present strategy could offer a promising route towards fast and robust quantum computation with superconducting circuits experimentally.展开更多
A novel treating technology for nitrogen removal from soybean wastewater was studied. The process for nitrogen removal was achieved by alternating aeration and mixing, combined with real\|time control strategies. Resu...A novel treating technology for nitrogen removal from soybean wastewater was studied. The process for nitrogen removal was achieved by alternating aeration and mixing, combined with real\|time control strategies. Results showed that the COD and total nitrogen removal rates are more than 90% and 92% at COD and total nitrogen loads of 1\^0-1\^2 kg COD/(kgMLSS·d) and 0\^20-0\^27 kg TN/(kgMLSS·d), respectively. In addition, it could improve sludge settling property. SVI value is less than 70 g/ml during the whole cycles. The method not only may be adapted to treat soybean wastewater with high nitrogen, but also may be applied to treat other high nitrogen wastewater.展开更多
An UASB＋Anoxic/Oxic （A/O） system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leaehate, t...An UASB＋Anoxic/Oxic （A/O） system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leaehate, the denitrifieation of NOx^--N in the reeireulation effluent from the elarifier was carried out in the UASB. The results showed that most biodegradable organic matters were removed by the denitrifieation in the UASB. The NH4^＋-N loading rate （ALR） of A/O reactor and operational temperature was 0.28- 0.60 kg NH4^＋-N/（m^3-d） and 17-29℃ during experimental period, respectively. The short-cut nitrification with nitrite accumulation efficiency of 90%-99% was stabilized during the whole experiment. The NH4^＋-N removal efficiency varied between 90% and 100%. When ALR was less than 0.45 kg NH4^＋-N/（m^3.d）, the NH4^＋-N removal efficiency was more than 98%. With the influent NH4^＋-N of 1200-1800 mg/L, the effluent NH4^＋-N was less than 15 mg/L. The shortcut nitrification and denitrifieation can save 40% carbon source, with a highly efficient denitrifieation taking place in the UASB. When the ratio of the feed COD to feed NH4^＋-N was only 2-3, the total inorganic nitrogen （TIN） removal efficiency attained 67%-80%. Besides, the sludge samples from A/O reactor were analyzed using FISH. The FISH analysis revealed that ammonia oxidation bacteria （AOB） accounted for 4% of the total eubaeterial population, whereas nitrite oxidation bacteria （NOB） accounted only for 0.2% of the total eubaeterial population.展开更多
Inverted batch distillation column(stripper) is opposed to a conventional batch distillation col-umn(rectifier). It has a storage vessel at the top and products leave the column at the bottom. The batch stripper is fa...Inverted batch distillation column(stripper) is opposed to a conventional batch distillation col-umn(rectifier). It has a storage vessel at the top and products leave the column at the bottom. The batch stripper is favourable to separate mixtures with a small amount of light components by removing the heavy components as bottom products. In this paper, we are presenting a shortcut procedure based on our earlier work for design and simulation of the inverted batch distillation column, which is equivalent to the Fenske-Underwood-Gilliland procedure for continuous distillation. Given a separation task, we propose to compute the minimum number of stages(Nbmin) and the minimum reboil ratio(Rbmin) required in a batch stripper,which are the stages and reboil ratio required in a hypothetical inverted batch distillation column operating in total reboil ratio or having an infinite number of stages, respectively. Then, it is shown that the performance of inverted batch columns with a finite number of stages and reboil ratios could be correlated in Gilliland coordinates with the minimum stages Nbmin and the minimum reboil ratio Rbmin.展开更多
Simultaneous biological phosphorus and nitrogen removal with enhanced anoxic phosphate uptake via nitrite was investigated in an anaerobic-aerobic-anoxic-aerobic sequencing batch reactor((AO)2 SBR). The system showed ...Simultaneous biological phosphorus and nitrogen removal with enhanced anoxic phosphate uptake via nitrite was investigated in an anaerobic-aerobic-anoxic-aerobic sequencing batch reactor((AO)2 SBR). The system showed stable phosphorus and nitrogen removal performance, and average removals for COD, TN and TP were 90%, 91% and 96%, respectively. The conditions of pH 7.5—8.0 and temperature 32℃ were found detrimental to nitrite oxidation bacteria but favorable to ammonia oxidizers, and the corresponding specific oxygen uptake rates(SOUR) for phase 1 and 2 of nitrification process were 0.7 and 15 mgO 2/(gVSS·h) in respect, which led to the nitrite accumulation in aerobic phase of(AO)2 SBR. Respiratory tests showed that 40 mgNO 2-N/L did not deteriorate the sludge activity drastically, and it implied that exposure of sludge to nitrite periodically enabled the biomass to have more tolerance capacity to resist the restraining effects from nitrite. In addition, batch tests were carried out and verified that denitrifying phosphorus accumulation organisms(DPAOs) could be enriched in a single sludge system coexisting with nitrifiers by introducing an anoxic phase in an anaerobic-aerobic SBR, and the ratio of the anoxic phosphate uptake capacity to aerobic phosphate uptake capacity was 45%. It was also found that nitrite(up to 20 mgNO 2-N/L) was not inhibitory to anoxic phosphate uptake and could serve as an electron acceptor like nitrate, but presented poorer efficiency compared with nitrate.展开更多
基金Project supported by National Natural Science Foundation of China (Grant Nos 10862001 and 10647001)Guangxi Natural Science Foundation (Grant No 0728042)
文摘P This paper studies how phase synchronization in complex networks depends on random shortcuts, using the uous chaotic Chua system as the nodes of the networks. It is found that for a given coupling strength when the number of random shortcuts is greater than a threshold the phase synchronization is induced. Phase synchronization becomes evident and reaches its maximum as the number of random shortcuts is further increased. These phenomena imply that random shortcuts can induce and enhance the phase synchronization in complex Chua systems. Furthermore, the paper also investigates the effects of the coupling strength and it is found that stronger coupling makes it easier to obtain the complete phase synchronization.
基金Supported by National Natural Science Foundation of China(Grant No.51275307)
文摘As a key to improve the performance of the interbay automated material handling system （AMHS） in 300 mm semiconductor wafer fabrication system, the real- time overhead hoist transport （OHT） dispatching problem has received much attention. This problem is first formu- lated as a special form of assignment problem and it is proved that more than one solution will be obtained by Hungarian algorithm simultaneously. Through proposing and strictly proving two propositions related to the char- acteristics of these solutions, a modified Hungarian algo- rithm is designed to distinguish these solutions. Finally, a new real-time OHT dispatching method is carefully designed by implementing the solution obtained by the modified Hungarian algorithm. The experimental results of discrete event simulations show that, compared with con- ventional Hungarian algorithm dispatching method, the proposed dispatching method that chooses the solution with the maximum variance respectively reduces on average 4 s of the average waiting time and average lead time of wafer lots, and its performance is rather stable in multiple dif- ferent scenarios of the interbay AMHS with different quantities of shortcuts. This research provides an efficient real-time OHT dispatching mechanism for the interbay AMHS with shortcuts and bypasses.
基金Project supported by the National Natural Science Foundation of China(Grant No.11464046)
文摘As one of the most promising candidates for implementing quantum computers, superconducting qubits（SQs） are adopted for fast generating the Greenberger–Horne–Zeilinger（GHZ） state by using invariants-based shortcuts. Three SQs are separated and connected by two coplanar waveguide resonators（CPWRs） capacitively. The complicated system is skillfully simplified to a three-state system, and a GHZ state among three SQs is fast generated with a very high fidelity and simple driving pulses. Numerical simulations indicate the scheme is insensitive to parameter deviations. Besides, the robustness of the scheme against decoherence is discussed in detail.
文摘A P2P scientific collaboration is a P2P network whose members can share documents, co-compile papers and codes, and communicate with each other instantly. From the simulation experiment we found that P2P collaboration system is a power-law network with a tail between -2 and -3.We utilized the algorithm that searches by high-degree shortcuts to improve the scalability of p2p collaboration system. The experimental result shows that the algorithm works better than random walk algorithm.
基金This work was supported by the Key R&D Program of Guangdong Province(Grant No.2018B030326001)the National Natural Science Foundation of China(Grant No.11874156)Science and Technology Program of Guangzhou(Grant No.2019050001).
文摘High-fidelity quantum gates are essential for large-scale quantum computation.However,any quantum manipulation will inevitably affected by noises,systematic errors and decoherence effects,which lead to infidelity of a target quantum task.Therefore,implementing high-fidelity,robust and fast quantum gates is highly desired.Here,we propose a fast and robust scheme to construct high-fidelity holonomic quantum gates for universal quantum computation based on resonant interaction of three-level quantum systems via shortcuts to adiabaticity.In our proposal,the target Hamiltonian to induce noncyclic non-Abelian geometric phases can be inversely engineered with less evolution time and demanding experimentally,leading to high-fidelity quantum gates in a simple setup.Besides,our scheme is readily realizable in physical system currently pursued for implementation of quantum computation.Therefore,our proposal represents a promising way towards fault-tolerant geometric quantum computation.
基金The work was supported by the National Natural Science Foundation of China(Grant No.12075193).
文摘Quantum batteries are energy storage devices that satisfy quantum mechanical principles.How to improve the battery’s performance such as stored energy and power is a crucial element in the quantum battery.Here,we investigate the charging and discharging dynamics of a three-level counterdiabatic stimulated Raman adiabatic passage quantum battery via shortcuts to adiabaticity,which can compensate for undesired transitions to realize a fast adiabatic evolution through the application of an additional control field to an initial Hamiltonian.The scheme can significantly speed up the charging and discharging processes of a three-level quantum battery and obtain more stored energy and higher power compared with the original stimulated Raman adiabatic passage.We explore the effect of both the amplitude and the delay time of driving fields on the performances of the quantum battery.Possible experimental implementation in superconducting circuit and nitrogen–vacancy center is also discussed.
基金supported by the National Natural Science Foundation of China(Grant No.11464046)
文摘We propose a scheme for a fast generating three-qubit W state in a superconducting system by using a technique of shortcuts to adiabaticity, Lewis–Riesenfeld invariants. Three identical superconducting qubits（SQs） are connected by two coplanar waveguide resonators（CPWRs） capacitively. Under a certain limit condition, we convert the complicated SQ system into a simple three-state system. By designing experimentally accessible harmonic pulses, a three-SQ W state is implemented with quite short operation time and high fidelity. Numerical simulations prove that the scheme is robust against the parameter deviation. In addition, we also give detailed discussion about the scheme robustness against decoherence.
基金Project supported by the Natural Science Foundation of Henan Province,China (Grant No. 212300410388)the “316” Project Plan of Xuchang University
文摘Construction of optimal gate operations is significant for quantum computation.Here an efficient scheme is proposed for performing shortcut-based quantum gates on superconducting qubits in circuit quantum electrodynamics(QED).Two four-level artificial atoms of Cooper-pair box circuits,having sufficient level anharmonicity,are placed in a common quantized field of circuit QED and are driven by individual classical microwaves.Without the effect of cross resonance,one-qubit NOT gate and phase gate in a decoupled atom can be implemented using the invariant-based shortcuts to adiabaticity.With the assistance of cavity bus,a one-step SWAP gate can be obtained within a composite qubit-photon-qubit system by inversely engineering the classical drivings.We further consider the gate realizations by adjusting the microwave fields.With the accessible decoherence rates,the shortcut-based gates have high fidelities.The present strategy could offer a promising route towards fast and robust quantum computation with superconducting circuits experimentally.
文摘A novel treating technology for nitrogen removal from soybean wastewater was studied. The process for nitrogen removal was achieved by alternating aeration and mixing, combined with real\|time control strategies. Results showed that the COD and total nitrogen removal rates are more than 90% and 92% at COD and total nitrogen loads of 1\^0-1\^2 kg COD/(kgMLSS·d) and 0\^20-0\^27 kg TN/(kgMLSS·d), respectively. In addition, it could improve sludge settling property. SVI value is less than 70 g/ml during the whole cycles. The method not only may be adapted to treat soybean wastewater with high nitrogen, but also may be applied to treat other high nitrogen wastewater.
基金Project supported by the National Natural Science Foundation of China(No.50521140075)the Funding Project for Academic Human Resource Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality(PHR(IHLB))the international cooperationproject financed by Beijing Municipal Science and Technology Commission.
文摘An UASB＋Anoxic/Oxic （A/O） system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leaehate, the denitrifieation of NOx^--N in the reeireulation effluent from the elarifier was carried out in the UASB. The results showed that most biodegradable organic matters were removed by the denitrifieation in the UASB. The NH4^＋-N loading rate （ALR） of A/O reactor and operational temperature was 0.28- 0.60 kg NH4^＋-N/（m^3-d） and 17-29℃ during experimental period, respectively. The short-cut nitrification with nitrite accumulation efficiency of 90%-99% was stabilized during the whole experiment. The NH4^＋-N removal efficiency varied between 90% and 100%. When ALR was less than 0.45 kg NH4^＋-N/（m^3.d）, the NH4^＋-N removal efficiency was more than 98%. With the influent NH4^＋-N of 1200-1800 mg/L, the effluent NH4^＋-N was less than 15 mg/L. The shortcut nitrification and denitrifieation can save 40% carbon source, with a highly efficient denitrifieation taking place in the UASB. When the ratio of the feed COD to feed NH4^＋-N was only 2-3, the total inorganic nitrogen （TIN） removal efficiency attained 67%-80%. Besides, the sludge samples from A/O reactor were analyzed using FISH. The FISH analysis revealed that ammonia oxidation bacteria （AOB） accounted for 4% of the total eubaeterial population, whereas nitrite oxidation bacteria （NOB） accounted only for 0.2% of the total eubaeterial population.
文摘Inverted batch distillation column(stripper) is opposed to a conventional batch distillation col-umn(rectifier). It has a storage vessel at the top and products leave the column at the bottom. The batch stripper is favourable to separate mixtures with a small amount of light components by removing the heavy components as bottom products. In this paper, we are presenting a shortcut procedure based on our earlier work for design and simulation of the inverted batch distillation column, which is equivalent to the Fenske-Underwood-Gilliland procedure for continuous distillation. Given a separation task, we propose to compute the minimum number of stages(Nbmin) and the minimum reboil ratio(Rbmin) required in a batch stripper,which are the stages and reboil ratio required in a hypothetical inverted batch distillation column operating in total reboil ratio or having an infinite number of stages, respectively. Then, it is shown that the performance of inverted batch columns with a finite number of stages and reboil ratios could be correlated in Gilliland coordinates with the minimum stages Nbmin and the minimum reboil ratio Rbmin.
文摘Simultaneous biological phosphorus and nitrogen removal with enhanced anoxic phosphate uptake via nitrite was investigated in an anaerobic-aerobic-anoxic-aerobic sequencing batch reactor((AO)2 SBR). The system showed stable phosphorus and nitrogen removal performance, and average removals for COD, TN and TP were 90%, 91% and 96%, respectively. The conditions of pH 7.5—8.0 and temperature 32℃ were found detrimental to nitrite oxidation bacteria but favorable to ammonia oxidizers, and the corresponding specific oxygen uptake rates(SOUR) for phase 1 and 2 of nitrification process were 0.7 and 15 mgO 2/(gVSS·h) in respect, which led to the nitrite accumulation in aerobic phase of(AO)2 SBR. Respiratory tests showed that 40 mgNO 2-N/L did not deteriorate the sludge activity drastically, and it implied that exposure of sludge to nitrite periodically enabled the biomass to have more tolerance capacity to resist the restraining effects from nitrite. In addition, batch tests were carried out and verified that denitrifying phosphorus accumulation organisms(DPAOs) could be enriched in a single sludge system coexisting with nitrifiers by introducing an anoxic phase in an anaerobic-aerobic SBR, and the ratio of the anoxic phosphate uptake capacity to aerobic phosphate uptake capacity was 45%. It was also found that nitrite(up to 20 mgNO 2-N/L) was not inhibitory to anoxic phosphate uptake and could serve as an electron acceptor like nitrate, but presented poorer efficiency compared with nitrate.
