We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and c...We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and comprehensive workflow that utilizes the quantum approximate optimization algorithm(QAOA).It facilitates the automatic conversion of the original problem into a quadratic unconstrained binary optimization(QUBO)model and its corresponding Ising model,which can be subsequently transformed into a weight graph.The core of Qcover relies on a graph decomposition-based classical algorithm,which efficiently derives the optimal parameters for the shallow QAOA circuit.Quafu-Qcover incorporates a dedicated compiler capable of translating QAOA circuits into physical quantum circuits that can be executed on Quafu cloud quantum computers.Compared to a general-purpose compiler,our compiler demonstrates the ability to generate shorter circuit depths,while also exhibiting superior speed performance.Additionally,the Qcover compiler has the capability to dynamically create a library of qubits coupling substructures in real-time,utilizing the most recent calibration data from the superconducting quantum devices.This ensures that computational tasks can be assigned to connected physical qubits with the highest fidelity.The Quafu-Qcover allows us to retrieve quantum computing sampling results using a task ID at any time,enabling asynchronous processing.Moreover,it incorporates modules for results preprocessing and visualization,facilitating an intuitive display of solutions for combinatorial optimization problems.We hope that Quafu-Qcover can serve as an instructive illustration for how to explore application problems on the Quafu cloud quantum computers.展开更多
The subsea production system is a vital equipment for offshore oil and gas production.The control system is one of the most important parts of it.Collecting and processing the signals of subsea sensors is the only way...The subsea production system is a vital equipment for offshore oil and gas production.The control system is one of the most important parts of it.Collecting and processing the signals of subsea sensors is the only way to judge whether the subsea production control system is normal.However,subsea sensors degrade rapidly due to harsh working environments and long service time.This leads to frequent false alarm incidents.A combinatorial reasoning-based abnormal sensor recognition method for subsea production control system is proposed.A combinatorial algorithm is proposed to group sensors.The long short-term memory network(LSTM)is used to establish a single inference model.A counting-based judging method is proposed to identify abnormal sensors.Field data from an offshore platform in the South China Sea is used to demonstrate the effect of the proposed method.The results show that the proposed method can identify the abnormal sensors effectively.展开更多
In this paper,we firstly establish a combinatorial identity with a free parameter x,and then by means of derivative operation,several summation formulae concerning classical and generalized harmonic numbers,as well as...In this paper,we firstly establish a combinatorial identity with a free parameter x,and then by means of derivative operation,several summation formulae concerning classical and generalized harmonic numbers,as well as binomial coefficients are derived.展开更多
An improved genetic algorithm is proposed to solve the problem of bad real-time performance or inability to get a global optimal/better solution when applying single-item auction （SIA） method or combinatorial auctio...An improved genetic algorithm is proposed to solve the problem of bad real-time performance or inability to get a global optimal/better solution when applying single-item auction （SIA） method or combinatorial auction method to multi-robot task allocation. The genetic algorithm based combinatorial auction （GACA） method which combines the basic-genetic algorithm with a new concept of ringed chromosome is used to solve the winner determination problem （WDP） of combinatorial auction. The simulation experiments are conducted in OpenSim, a multi-robot simulator. The results show that GACA can get a satisfying solution in a reasonable shot time, and compared with SIA or parthenogenesis algorithm combinatorial auction （PGACA） method, it is the simplest and has higher search efficiency, also, GACA can get a global better/optimal solution and satisfy the high real-time requirement of multi-robot task allocation.展开更多
Fast synthesis and screening of materials are vital to the advance of materials science and are an essential component of the Materials Genome Initiative. Here we use copper-oxide superconductors as an example to demo...Fast synthesis and screening of materials are vital to the advance of materials science and are an essential component of the Materials Genome Initiative. Here we use copper-oxide superconductors as an example to demonstrate the power of integrating combinatorial molecular beam epitaxy synthesis with high-throughput electric transport measurements. Leveraging this method, we have generated a phase diagram with more than 800 compositions in order to unravel the doping dependence of interface superconductivity. In another application of the same method, we have studied the superconductorto-insulator quantum phase transition with unprecedented accuracy in tuning the chemical doping level.展开更多
By virtue of the method of integration within ordered product(IWOP)of operators we find the normally ordered form of the optical wavelet-fractional squeezing combinatorial transform(WFrST)operator.The way we successfu...By virtue of the method of integration within ordered product(IWOP)of operators we find the normally ordered form of the optical wavelet-fractional squeezing combinatorial transform(WFrST)operator.The way we successfully combine them to realize the integration transform kernel of WFr ST is making full use of the completeness relation of Dirac’s ket–bra representation.The WFr ST can play role in analyzing and recognizing quantum states,for instance,we apply this new transform to identify the vacuum state,the single-particle state,and their superposition state.展开更多
Many problems in science,engineering and real life are related to the combinatorial optimization.However,many combinatorial optimization problems belong to a class of the NP-hard problems,and their globally optimal so...Many problems in science,engineering and real life are related to the combinatorial optimization.However,many combinatorial optimization problems belong to a class of the NP-hard problems,and their globally optimal solutions are usually difficult to solve.Therefore,great attention has been attracted to the algorithms of searching the globally optimal solution or near-optimal solution for the combinatorial optimization problems.As a typical combinatorial optimization problem,the traveling salesman problem(TSP)often serves as a touchstone for novel approaches.It has been found that natural systems,particularly brain nervous systems,work at the critical region between order and disorder,namely,on the edge of chaos.In this work,an algorithm for the combinatorial optimization problems is proposed based on the neural networks on the edge of chaos(ECNN).The algorithm is then applied to TSPs of 10 cities,21 cities,48 cities and 70 cities.The results show that ECNN algorithm has strong ability to drive the networks away from local minimums.Compared with the transiently chaotic neural network(TCNN),the stochastic chaotic neural network(SCNN)algorithms and other optimization algorithms,much higher rates of globally optimal solutions and near-optimal solutions are obtained with ECNN algorithm.To conclude,our algorithm provides an effective way for solving the combinatorial optimization problems.展开更多
Using approximation technique, we introduce the concepts of canonical extension and symmetrio integral for jump process and obtain some results in the chaotic form.
In this paper, a magnetooptic chip was prepared on Si wafer by combinatorial Ga+ implantation into ion sputtered Co7Ag93 film. The surface morphology of each unit of the chip was detected by AFM, while their Kerr effe...In this paper, a magnetooptic chip was prepared on Si wafer by combinatorial Ga+ implantation into ion sputtered Co7Ag93 film. The surface morphology of each unit of the chip was detected by AFM, while their Kerr effect was measnred by MOKE equipment. It is observed that the maximum Kerr rotation (MKR) occurs when thc incident photon energy is around 3.8-3.9 eV. Summarization of MKR wer sus implanted Ga+ dose shows that the MKR enhancement by Ga+ implantation can be characterized as incubation, enhancement and saturation regions. Considering the mutual solubility and surface morphology transition after annealing, it is suggested that Ga+ tends to form CoCa and/or CoCa3 intermetallic compounds. Before the formation of CoGa3 compounds, no apparent MKR enhancement could be obserwed. While when the surface is half occupied by forest-like CoCa3 compounds, MKR enhancement will be saturated. By comparison of the maximum Kerr rotation with the cone areal density, it can be induced that not only the bulk concentration and structure, but also the surface morphology plays an important role in magnctooptic Kerr effect.展开更多
电动汽车(electric vehicle,EV)充电行为存在强随机性与高波动性,使其充电站短期充电负荷预测精度较低,作为移动电力存储和负载资源参与车到网(vehicle to grid,V2G)服务中,其调度中心需要在短时间内预测EV的充电负荷来改善其对电网负...电动汽车(electric vehicle,EV)充电行为存在强随机性与高波动性,使其充电站短期充电负荷预测精度较低,作为移动电力存储和负载资源参与车到网(vehicle to grid,V2G)服务中,其调度中心需要在短时间内预测EV的充电负荷来改善其对电网负荷的影响。为了提高EV充电站短期充电负荷预测精度,提出一种冠豪猪优化器变分模态分解双向长短期记忆神经网络(crested porcupine optimizer variational mode decomposition bidirectional long short term memory,CPO VMD BiLSTM)组合模型进行EV充电站短期充电负荷预测的方法。首先,考虑影响EV充电负荷的多种因素和历史充电站充电负荷共同构成输入特征矩阵。然后利用CPO算法对VMD其核心参数进行优化搜索,实现参数自适应优化设置。之后采用CPO VMD对历史充电负荷数据进行分解,弱化负荷的非平稳性,捕捉其局部特征。最后在BiLSTM模型中输入分解后的特征矩阵来实现充电站短期充电负荷的预测目标。以美国ANN DATA公开数据集中位于加州理工大学校园内EV充电站的历史充电负荷数据作为实际算例,与独立模型、未优化组合模型、优化组合模型进行对比,均方根误差(root mean squared error,RMSE)和平均绝对误差(mean absolute error,MAE)平均降低了41.23%和59.04%。因此,验证了提出方法在充电站充电负荷短期预测中精度的提高和实用性。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.92365206)the support of the China Postdoctoral Science Foundation(Certificate Number:2023M740272)+1 种基金supported by the National Natural Science Foundation of China(Grant No.12247168)China Postdoctoral Science Foundation(Certificate Number:2022TQ0036)。
文摘We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and comprehensive workflow that utilizes the quantum approximate optimization algorithm(QAOA).It facilitates the automatic conversion of the original problem into a quadratic unconstrained binary optimization(QUBO)model and its corresponding Ising model,which can be subsequently transformed into a weight graph.The core of Qcover relies on a graph decomposition-based classical algorithm,which efficiently derives the optimal parameters for the shallow QAOA circuit.Quafu-Qcover incorporates a dedicated compiler capable of translating QAOA circuits into physical quantum circuits that can be executed on Quafu cloud quantum computers.Compared to a general-purpose compiler,our compiler demonstrates the ability to generate shorter circuit depths,while also exhibiting superior speed performance.Additionally,the Qcover compiler has the capability to dynamically create a library of qubits coupling substructures in real-time,utilizing the most recent calibration data from the superconducting quantum devices.This ensures that computational tasks can be assigned to connected physical qubits with the highest fidelity.The Quafu-Qcover allows us to retrieve quantum computing sampling results using a task ID at any time,enabling asynchronous processing.Moreover,it incorporates modules for results preprocessing and visualization,facilitating an intuitive display of solutions for combinatorial optimization problems.We hope that Quafu-Qcover can serve as an instructive illustration for how to explore application problems on the Quafu cloud quantum computers.
基金supported by the National Key Research and Development Program of China (No.2022YFC2806102)the National Natural Science Foundation of China (No.52171287,52325107)+3 种基金High-tech Ship Research Project of Ministry of Industry and Information Technology (No.2023GXB01-05-004-03,No.GXBZH2022-293)the Science Foundation for Distinguished Young Scholars of Shandong Province (No.ZR2022JQ25)the Taishan Scholars Project (No.tsqn201909063)the Fundamental Research Funds for the Central Universities (No.24CX10006A)。
文摘The subsea production system is a vital equipment for offshore oil and gas production.The control system is one of the most important parts of it.Collecting and processing the signals of subsea sensors is the only way to judge whether the subsea production control system is normal.However,subsea sensors degrade rapidly due to harsh working environments and long service time.This leads to frequent false alarm incidents.A combinatorial reasoning-based abnormal sensor recognition method for subsea production control system is proposed.A combinatorial algorithm is proposed to group sensors.The long short-term memory network(LSTM)is used to establish a single inference model.A counting-based judging method is proposed to identify abnormal sensors.Field data from an offshore platform in the South China Sea is used to demonstrate the effect of the proposed method.The results show that the proposed method can identify the abnormal sensors effectively.
基金Supported by Zhoukou Normal University High-Level Talents Start-Up Funds Research Project(Grant No.ZKNUC2022007)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX240725).
文摘In this paper,we firstly establish a combinatorial identity with a free parameter x,and then by means of derivative operation,several summation formulae concerning classical and generalized harmonic numbers,as well as binomial coefficients are derived.
基金Sponsored by Excellent Young Scholars Research Fund of Beijing Institute of Technology(00Y03-13)
文摘An improved genetic algorithm is proposed to solve the problem of bad real-time performance or inability to get a global optimal/better solution when applying single-item auction （SIA） method or combinatorial auction method to multi-robot task allocation. The genetic algorithm based combinatorial auction （GACA） method which combines the basic-genetic algorithm with a new concept of ringed chromosome is used to solve the winner determination problem （WDP） of combinatorial auction. The simulation experiments are conducted in OpenSim, a multi-robot simulator. The results show that GACA can get a satisfying solution in a reasonable shot time, and compared with SIA or parthenogenesis algorithm combinatorial auction （PGACA） method, it is the simplest and has higher search efficiency, also, GACA can get a global better/optimal solution and satisfy the high real-time requirement of multi-robot task allocation.
文摘Fast synthesis and screening of materials are vital to the advance of materials science and are an essential component of the Materials Genome Initiative. Here we use copper-oxide superconductors as an example to demonstrate the power of integrating combinatorial molecular beam epitaxy synthesis with high-throughput electric transport measurements. Leveraging this method, we have generated a phase diagram with more than 800 compositions in order to unravel the doping dependence of interface superconductivity. In another application of the same method, we have studied the superconductorto-insulator quantum phase transition with unprecedented accuracy in tuning the chemical doping level.
基金supported by the National Natural Science Foundation of China(Grant No.11304126)the College Students’Innovation Training Program(Grant No.202110299696X)。
文摘By virtue of the method of integration within ordered product(IWOP)of operators we find the normally ordered form of the optical wavelet-fractional squeezing combinatorial transform(WFrST)operator.The way we successfully combine them to realize the integration transform kernel of WFr ST is making full use of the completeness relation of Dirac’s ket–bra representation.The WFr ST can play role in analyzing and recognizing quantum states,for instance,we apply this new transform to identify the vacuum state,the single-particle state,and their superposition state.
基金supported by the National Natural Science Foundation of China(Grant No.12074335)the National Science and Technology Major Project of the Ministry of Science and Technology of China(Grant No.2016YFA0300402).
文摘Many problems in science,engineering and real life are related to the combinatorial optimization.However,many combinatorial optimization problems belong to a class of the NP-hard problems,and their globally optimal solutions are usually difficult to solve.Therefore,great attention has been attracted to the algorithms of searching the globally optimal solution or near-optimal solution for the combinatorial optimization problems.As a typical combinatorial optimization problem,the traveling salesman problem(TSP)often serves as a touchstone for novel approaches.It has been found that natural systems,particularly brain nervous systems,work at the critical region between order and disorder,namely,on the edge of chaos.In this work,an algorithm for the combinatorial optimization problems is proposed based on the neural networks on the edge of chaos(ECNN).The algorithm is then applied to TSPs of 10 cities,21 cities,48 cities and 70 cities.The results show that ECNN algorithm has strong ability to drive the networks away from local minimums.Compared with the transiently chaotic neural network(TCNN),the stochastic chaotic neural network(SCNN)algorithms and other optimization algorithms,much higher rates of globally optimal solutions and near-optimal solutions are obtained with ECNN algorithm.To conclude,our algorithm provides an effective way for solving the combinatorial optimization problems.
基金Supported in part by National Natural Science Foundation of China.
文摘Using approximation technique, we introduce the concepts of canonical extension and symmetrio integral for jump process and obtain some results in the chaotic form.
基金Supported by National Natural Science Foundation of China (No.19975067 and No.10075074)
文摘In this paper, a magnetooptic chip was prepared on Si wafer by combinatorial Ga+ implantation into ion sputtered Co7Ag93 film. The surface morphology of each unit of the chip was detected by AFM, while their Kerr effect was measnred by MOKE equipment. It is observed that the maximum Kerr rotation (MKR) occurs when thc incident photon energy is around 3.8-3.9 eV. Summarization of MKR wer sus implanted Ga+ dose shows that the MKR enhancement by Ga+ implantation can be characterized as incubation, enhancement and saturation regions. Considering the mutual solubility and surface morphology transition after annealing, it is suggested that Ga+ tends to form CoCa and/or CoCa3 intermetallic compounds. Before the formation of CoGa3 compounds, no apparent MKR enhancement could be obserwed. While when the surface is half occupied by forest-like CoCa3 compounds, MKR enhancement will be saturated. By comparison of the maximum Kerr rotation with the cone areal density, it can be induced that not only the bulk concentration and structure, but also the surface morphology plays an important role in magnctooptic Kerr effect.
文摘电动汽车(electric vehicle,EV)充电行为存在强随机性与高波动性,使其充电站短期充电负荷预测精度较低,作为移动电力存储和负载资源参与车到网(vehicle to grid,V2G)服务中,其调度中心需要在短时间内预测EV的充电负荷来改善其对电网负荷的影响。为了提高EV充电站短期充电负荷预测精度,提出一种冠豪猪优化器变分模态分解双向长短期记忆神经网络(crested porcupine optimizer variational mode decomposition bidirectional long short term memory,CPO VMD BiLSTM)组合模型进行EV充电站短期充电负荷预测的方法。首先,考虑影响EV充电负荷的多种因素和历史充电站充电负荷共同构成输入特征矩阵。然后利用CPO算法对VMD其核心参数进行优化搜索,实现参数自适应优化设置。之后采用CPO VMD对历史充电负荷数据进行分解,弱化负荷的非平稳性,捕捉其局部特征。最后在BiLSTM模型中输入分解后的特征矩阵来实现充电站短期充电负荷的预测目标。以美国ANN DATA公开数据集中位于加州理工大学校园内EV充电站的历史充电负荷数据作为实际算例,与独立模型、未优化组合模型、优化组合模型进行对比,均方根误差(root mean squared error,RMSE)和平均绝对误差(mean absolute error,MAE)平均降低了41.23%和59.04%。因此,验证了提出方法在充电站充电负荷短期预测中精度的提高和实用性。
