AIM:To investigate whether the two-step strategy[conjunctival flap covering surgery(CFCS)combined with secondary deep anterior lamellar keratoplasty(DALK)]is effective for patients with high-risk fungal keratitis(FK)....AIM:To investigate whether the two-step strategy[conjunctival flap covering surgery(CFCS)combined with secondary deep anterior lamellar keratoplasty(DALK)]is effective for patients with high-risk fungal keratitis(FK).METHODS:In this noncomparative,retrospective case series,10 subjects(6 males,4 females)with a mean age of 56.5±7.1(range 47-72)y with high-risk FK undergone the two-step strategy were included.Reported outcome measures were healing of the corneal ulcer,recurrence of FK,reject reaction,improvement in best corrected visual acuity(BCVA)and relevant complications.RESULTS:The average diameter of corneal infiltrates was 7.50±0.39 mm,ranging from 6.94 to 8.13 mm.The mean depth of corneal infiltrates was 422.4±77.1μm,ranging from 350 to 535μm.The mean corneal thickness was 597.4±117.3μm,ranging from 458 to 851μm.Hypopyon and endothelial plaques were presented in all patients.The period between the two steps was 3.65±0.9(ranging from 3 to 5)mo.The graft diameter was 7.75±0.39 mm.At the last follow-up(average 9.25±3.39,ranging from 5.5 to 17mo),no fungal recurrence or graft rejection appeared,and all patients showed improvement of BCVA.One patient suffered from liver function impairment due to oral voriconazole for 4wk and recovered spontaneously after 1wk of drug withdrawal.CONCLUSION:The two-step strategy is safe and effective in the treatment of high-risk FK by transforming intentional therapeutic penetrating keratoplasty during acute infection to later optical DALK.It is a practical strategy,especially in areas lacking fresh donor corneas and eye bank services.展开更多
The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Opti...The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Optimal guidance mechanism of the flexible load based on strategies of direct load control and time-of-use.First,this study proposes a period partitioning model,which is based on a moving boundary technique with constraint factors,and the Dunn Validity Index(DVI)is used as the objective to solve the period partitioning.Second,a control strategy for the curtailable flexible load is investigated,and a TOU strategy is utilized for further modifying load curve.Third,a price demand response strategy for adjusting transferable load is proposed in this paper.Finally,through the case study analysis of typical daily flexible load curve,the efficiency and correctness of the proposed method and model are validated and proved.展开更多
[Objective] For preparing the biopesticide of Bacillus subtilis B579 with high spore concentration,the sporulation conditions were optimized.[Method] Two-step fermentation control strategy was used,in which,the first ...[Objective] For preparing the biopesticide of Bacillus subtilis B579 with high spore concentration,the sporulation conditions were optimized.[Method] Two-step fermentation control strategy was used,in which,the first phase(0-10 h)was to improve cell growth,and the second phase(10-30 h)was to promote spore formation.Four factors including initial glucose concentration,fermentation pH,temperature(in the second phase)and shaking speed(in the second phase)were optimized using the methods of single factor test and orthogonal experiment.[Result] The initial glucose concentration showed a significant effect on sporulation.The optimal conditions for the spore formation of B.subtilis B579 were as follows:initial glucose concentration 5 g/L,fermentation pH 7.0,the temperature for the first phase 37 ℃,and the shaking speed for the first phase 180 r/min,the temperature for the second phase 40 ℃,and the shaking speed for the second phase 200 r/min;in addition,the first phase was 10 h and the second phase of fermentation was conducted for 30 h.Under such conditions,the spore concentration and spore formation rate could reach 9.43×108 CFU/ml and 90.99%,respectively,which represented 6.70-fold and 2.43-fold increase compared with those before optimization.[Conclusion] The spores concentration of biocontrol agent was improved using two-step control strategy,which provided the basis for biopesticide production in large scale.展开更多
We propose a two-step quantum secure direct communication (QSDC) protocol with hyperentanglement in both the spatial-mode and the polarization degrees of freedom of photon pairs which can in principle be produced wi...We propose a two-step quantum secure direct communication (QSDC) protocol with hyperentanglement in both the spatial-mode and the polarization degrees of freedom of photon pairs which can in principle be produced with a beta barium borate crystal. The secret message can be encoded on the photon pairs with unitary operations in these two degrees of freedom independently. This QSDC protocol has a higher capacity than the original two-step QSDC protocol as each photon pair can carry 4 bits of information. Compared with the QSDC protocol based on hyperdense coding, this QSDC protocol has the immunity to Trojan horse attack strategies with the process for determining the number of the photons in each quantum signal as it is a one-way quantum communication protocol.展开更多
To analyze the security of two-step quantum direct communication protocol (QDCP) by using Einstein-Podolsky Rosen pair proposed by Deng et al. [Phys. Rev. A 68 (2003)042317] in collective-rotation noise channel, a...To analyze the security of two-step quantum direct communication protocol (QDCP) by using Einstein-Podolsky Rosen pair proposed by Deng et al. [Phys. Rev. A 68 (2003)042317] in collective-rotation noise channel, an excellent model of noise analysis is proposed. In the security analysis, the method of the entropy theory is introduced, and is compared with QDCP, an error rate point Qo(M : (Q0, 1.0)) is given. In different noise levels, if Eve wants to obtain the same amount of information, the error rate Q is distinguishable. The larger the noise level ~ is, the larger the error rate Q is. When the noise level ~ is lower than 11%, the high error rate is 0.153 without eavesdropping. Lastly, the security of the proposed protocol is discussed. It turns out that the quantum channel will be safe when Q 〈 0.153. Similarly, if error rate Q〉 0.153 = Q0, eavesdropping information I 〉 1, which means that there exist eavesdroppers in the quantum channel, and the quantum channel will not be safe anymore.展开更多
The antenna geometry strategy for direction finding (DF) with multiple-input multiple-output (MIMO) radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional an...The antenna geometry strategy for direction finding (DF) with multiple-input multiple-output (MIMO) radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional antenna geometry with a prior direction, the trace-optimal (TO) criterion (minimizing the trace) on the av- erage Cramer-Rao bound (CRB) matrix is employed. A qualitative explanation for antenna geometry is provided, which is a combi- natorial optimization problem. In the numerical example section, it is shown that the antenna geometries, designed by the proposed strategy, outperform the representative DF antenna geometries.展开更多
A two-step information extraction method is presented to capture the specific index-related information more accurately.In the first step,the overall process variables are separated into two sets based on Pearson corr...A two-step information extraction method is presented to capture the specific index-related information more accurately.In the first step,the overall process variables are separated into two sets based on Pearson correlation coefficient.One is process variables strongly related to the specific index and the other is process variables weakly related to the specific index.Through performing principal component analysis(PCA)on the two sets,the directions of latent variables have changed.In other words,the correlation between latent variables in the set with strong correlation and the specific index may become weaker.Meanwhile,the correlation between latent variables in the set with weak correlation and the specific index may be enhanced.In the second step,the two sets are further divided into a subset strongly related to the specific index and a subset weakly related to the specific index from the perspective of latent variables using Pearson correlation coefficient,respectively.Two subsets strongly related to the specific index form a new subspace related to the specific index.Then,a hybrid monitoring strategy based on predicted specific index using partial least squares(PLS)and T2statistics-based method is proposed for specific index-related process monitoring using comprehensive information.Predicted specific index reflects real-time information for the specific index.T2statistics are used to monitor specific index-related information.Finally,the proposed method is applied to Tennessee Eastman(TE).The results indicate the effectiveness of the proposed method.展开更多
Photovoltaics,energy storage,direct current and flexibility(PEDF)are important pillars of achievement on the path to manufacturing nearly zero energy buildings(NZEBs).HVAC systems,which are an important part of public...Photovoltaics,energy storage,direct current and flexibility(PEDF)are important pillars of achievement on the path to manufacturing nearly zero energy buildings(NZEBs).HVAC systems,which are an important part of public buildings,play a key role in adapting to PDEF systems.This research studied the basic principles and operational control strategies of a DC inverter heat pump using a DC distribution network with the aim of contributing to the development and application of small DC distribution systems.Along with the characteristics of a DC distribution network and different operating conditions,a DC inverter heat pump has the ability to adapt to changes in the DC bus voltage and adds flexibility to the system.Theoretical models of the DC inverter heat pump integrated with an ice storage unit were developed.The control strategies of the DC inverter heat pump system considered the influence of both room temperature and varied bus voltage.A simulation study was conducted using MATLAB&Simulink software with simulation results validated by experimental data.The results showed that:(1)The bus fluctuation under the rated working voltage had little effect on the operation of the unit;(2)When the bus voltage was fluctuating from 80%-90%or 105%-107%,the heat pump could still operate normally by reducing the frequency;(3)When the bus voltage was less than 80%or more than 107%,the unit needed to be shut down for the sake of equipment safety,so that the energy storage device could adjust to the sharp decrease or rise of voltage.展开更多
为解决船舶中压直流(medium voltage direct current,MVDC)电力系统直流电流开断困难,以及发生短路时故障电流上升率高且峰值大的问题,提出一种基于耦合电抗器的阻容限流型固态直流断路器拓扑。以晶闸管(silicon controlled rectifier,S...为解决船舶中压直流(medium voltage direct current,MVDC)电力系统直流电流开断困难,以及发生短路时故障电流上升率高且峰值大的问题,提出一种基于耦合电抗器的阻容限流型固态直流断路器拓扑。以晶闸管(silicon controlled rectifier,SCR)作为主开断器件,通过耦合电抗器来辅助晶闸管开断,并在直流系统发生故障时,通过换流过程将阻容限流元件接入,有效限制故障电流上升率和峰值,减少故障开断所需时间。基于所提拓扑设计了6 kV/4.2 kA的直流断路器模型,在PSCAD/EMTDC中进行仿真,并与现有拓扑进行对比分析。仿真结果表明:所设计断路器可针对直流系统不同的运行状态,按照不同的控制策略顺利完成对直流电流的开断,并且在开断速度、限流能力和金属氧化物避雷器(metal oxide arrester,MOA)耗能方面均具有一定优势。展开更多
针对传统最大似然波达方向(maximum likelihood direction of arrival,ML-DOA)估计存在计算量大、估计精度差等问题,本文提出一种采用改进帝王蝶优化算法(improved monarch butterfly optimization algorithm,IMBO)的ML-DOA估计方法。I...针对传统最大似然波达方向(maximum likelihood direction of arrival,ML-DOA)估计存在计算量大、估计精度差等问题,本文提出一种采用改进帝王蝶优化算法(improved monarch butterfly optimization algorithm,IMBO)的ML-DOA估计方法。IMBO算法通过精英反向学习策略对初始帝王蝶种群进行优化,得到适应度值较优的初始帝王蝶个体,进而能够改善帝王蝶种群的多样性;引入差分进化算法启发的变异操作以及自适应策略对帝王蝶个体的寻优方式进行改进,扩大了算法的搜索空间;引入了高斯-柯西变异算子,自适应调整变异步长,避免算法陷入局部最优。将IMBO应用于ML-DOA,实验表明,与传统的DOA估计算法相比,在不同信源数目、信噪比以及种群数量下,本文提出的算法收敛性能更好,均方根误差更低,运算量更小。展开更多
基金Supported by the National Natural Science Foundation of China(No.82171025No.82070934)+2 种基金the Fundamental Research Funds for the Central Universities(No.HUST:2019kfy XMBZ065)the Key Research and Development Program of Hubei Province(No.2021BCA146)the Clinical Research Foundation of Wuhan Union Hospital(No.2021xhlcyj03)。
文摘AIM:To investigate whether the two-step strategy[conjunctival flap covering surgery(CFCS)combined with secondary deep anterior lamellar keratoplasty(DALK)]is effective for patients with high-risk fungal keratitis(FK).METHODS:In this noncomparative,retrospective case series,10 subjects(6 males,4 females)with a mean age of 56.5±7.1(range 47-72)y with high-risk FK undergone the two-step strategy were included.Reported outcome measures were healing of the corneal ulcer,recurrence of FK,reject reaction,improvement in best corrected visual acuity(BCVA)and relevant complications.RESULTS:The average diameter of corneal infiltrates was 7.50±0.39 mm,ranging from 6.94 to 8.13 mm.The mean depth of corneal infiltrates was 422.4±77.1μm,ranging from 350 to 535μm.The mean corneal thickness was 597.4±117.3μm,ranging from 458 to 851μm.Hypopyon and endothelial plaques were presented in all patients.The period between the two steps was 3.65±0.9(ranging from 3 to 5)mo.The graft diameter was 7.75±0.39 mm.At the last follow-up(average 9.25±3.39,ranging from 5.5 to 17mo),no fungal recurrence or graft rejection appeared,and all patients showed improvement of BCVA.One patient suffered from liver function impairment due to oral voriconazole for 4wk and recovered spontaneously after 1wk of drug withdrawal.CONCLUSION:The two-step strategy is safe and effective in the treatment of high-risk FK by transforming intentional therapeutic penetrating keratoplasty during acute infection to later optical DALK.It is a practical strategy,especially in areas lacking fresh donor corneas and eye bank services.
基金supported by open fund of state key laboratory of operation and control of renewable energy&storage systems(China electric power research institute)(No.NYB51202201709).
文摘The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Optimal guidance mechanism of the flexible load based on strategies of direct load control and time-of-use.First,this study proposes a period partitioning model,which is based on a moving boundary technique with constraint factors,and the Dunn Validity Index(DVI)is used as the objective to solve the period partitioning.Second,a control strategy for the curtailable flexible load is investigated,and a TOU strategy is utilized for further modifying load curve.Third,a price demand response strategy for adjusting transferable load is proposed in this paper.Finally,through the case study analysis of typical daily flexible load curve,the efficiency and correctness of the proposed method and model are validated and proved.
基金Supported by the Natural Science Foundation of Tianjin(09JCZDJC19100)Scientific Research Fund of Tianjin Scienceand Technology University(20090403)~~
文摘[Objective] For preparing the biopesticide of Bacillus subtilis B579 with high spore concentration,the sporulation conditions were optimized.[Method] Two-step fermentation control strategy was used,in which,the first phase(0-10 h)was to improve cell growth,and the second phase(10-30 h)was to promote spore formation.Four factors including initial glucose concentration,fermentation pH,temperature(in the second phase)and shaking speed(in the second phase)were optimized using the methods of single factor test and orthogonal experiment.[Result] The initial glucose concentration showed a significant effect on sporulation.The optimal conditions for the spore formation of B.subtilis B579 were as follows:initial glucose concentration 5 g/L,fermentation pH 7.0,the temperature for the first phase 37 ℃,and the shaking speed for the first phase 180 r/min,the temperature for the second phase 40 ℃,and the shaking speed for the second phase 200 r/min;in addition,the first phase was 10 h and the second phase of fermentation was conducted for 30 h.Under such conditions,the spore concentration and spore formation rate could reach 9.43×108 CFU/ml and 90.99%,respectively,which represented 6.70-fold and 2.43-fold increase compared with those before optimization.[Conclusion] The spores concentration of biocontrol agent was improved using two-step control strategy,which provided the basis for biopesticide production in large scale.
基金supported by the Natural Science Foundation of Jiangsu Provincial Universities, China (Grant No. 10KJB180004)
文摘We propose a two-step quantum secure direct communication (QSDC) protocol with hyperentanglement in both the spatial-mode and the polarization degrees of freedom of photon pairs which can in principle be produced with a beta barium borate crystal. The secret message can be encoded on the photon pairs with unitary operations in these two degrees of freedom independently. This QSDC protocol has a higher capacity than the original two-step QSDC protocol as each photon pair can carry 4 bits of information. Compared with the QSDC protocol based on hyperdense coding, this QSDC protocol has the immunity to Trojan horse attack strategies with the process for determining the number of the photons in each quantum signal as it is a one-way quantum communication protocol.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61472048,61402058,61272511,61472046,61202082 and 61370194the Beijing Natural Science Foundation under Grant No 4152038the China Postdoctoral Science Foundation Funded Project under Grant No 2014M561826
文摘To analyze the security of two-step quantum direct communication protocol (QDCP) by using Einstein-Podolsky Rosen pair proposed by Deng et al. [Phys. Rev. A 68 (2003)042317] in collective-rotation noise channel, an excellent model of noise analysis is proposed. In the security analysis, the method of the entropy theory is introduced, and is compared with QDCP, an error rate point Qo(M : (Q0, 1.0)) is given. In different noise levels, if Eve wants to obtain the same amount of information, the error rate Q is distinguishable. The larger the noise level ~ is, the larger the error rate Q is. When the noise level ~ is lower than 11%, the high error rate is 0.153 without eavesdropping. Lastly, the security of the proposed protocol is discussed. It turns out that the quantum channel will be safe when Q 〈 0.153. Similarly, if error rate Q〉 0.153 = Q0, eavesdropping information I 〉 1, which means that there exist eavesdroppers in the quantum channel, and the quantum channel will not be safe anymore.
基金supported by the National Natural Science Foundation of China(6107211761302142)
文摘The antenna geometry strategy for direction finding (DF) with multiple-input multiple-output (MIMO) radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional antenna geometry with a prior direction, the trace-optimal (TO) criterion (minimizing the trace) on the av- erage Cramer-Rao bound (CRB) matrix is employed. A qualitative explanation for antenna geometry is provided, which is a combi- natorial optimization problem. In the numerical example section, it is shown that the antenna geometries, designed by the proposed strategy, outperform the representative DF antenna geometries.
基金Projects(61374140,61673173)supported by the National Natural Science Foundation of ChinaProjects(222201717006,222201714031)supported by the Fundamental Research Funds for the Central Universities,China
文摘A two-step information extraction method is presented to capture the specific index-related information more accurately.In the first step,the overall process variables are separated into two sets based on Pearson correlation coefficient.One is process variables strongly related to the specific index and the other is process variables weakly related to the specific index.Through performing principal component analysis(PCA)on the two sets,the directions of latent variables have changed.In other words,the correlation between latent variables in the set with strong correlation and the specific index may become weaker.Meanwhile,the correlation between latent variables in the set with weak correlation and the specific index may be enhanced.In the second step,the two sets are further divided into a subset strongly related to the specific index and a subset weakly related to the specific index from the perspective of latent variables using Pearson correlation coefficient,respectively.Two subsets strongly related to the specific index form a new subspace related to the specific index.Then,a hybrid monitoring strategy based on predicted specific index using partial least squares(PLS)and T2statistics-based method is proposed for specific index-related process monitoring using comprehensive information.Predicted specific index reflects real-time information for the specific index.T2statistics are used to monitor specific index-related information.Finally,the proposed method is applied to Tennessee Eastman(TE).The results indicate the effectiveness of the proposed method.
基金funded by State Grid Science&Technology Project“Research and Demonstration of Key Technologies on Electric-Heating Collaboration Cross-Network Mutual Supply for Typical Regional Clean Energy”,Grant Number 5400-202111575A-0-5-SF.
文摘Photovoltaics,energy storage,direct current and flexibility(PEDF)are important pillars of achievement on the path to manufacturing nearly zero energy buildings(NZEBs).HVAC systems,which are an important part of public buildings,play a key role in adapting to PDEF systems.This research studied the basic principles and operational control strategies of a DC inverter heat pump using a DC distribution network with the aim of contributing to the development and application of small DC distribution systems.Along with the characteristics of a DC distribution network and different operating conditions,a DC inverter heat pump has the ability to adapt to changes in the DC bus voltage and adds flexibility to the system.Theoretical models of the DC inverter heat pump integrated with an ice storage unit were developed.The control strategies of the DC inverter heat pump system considered the influence of both room temperature and varied bus voltage.A simulation study was conducted using MATLAB&Simulink software with simulation results validated by experimental data.The results showed that:(1)The bus fluctuation under the rated working voltage had little effect on the operation of the unit;(2)When the bus voltage was fluctuating from 80%-90%or 105%-107%,the heat pump could still operate normally by reducing the frequency;(3)When the bus voltage was less than 80%or more than 107%,the unit needed to be shut down for the sake of equipment safety,so that the energy storage device could adjust to the sharp decrease or rise of voltage.
文摘为解决船舶中压直流(medium voltage direct current,MVDC)电力系统直流电流开断困难,以及发生短路时故障电流上升率高且峰值大的问题,提出一种基于耦合电抗器的阻容限流型固态直流断路器拓扑。以晶闸管(silicon controlled rectifier,SCR)作为主开断器件,通过耦合电抗器来辅助晶闸管开断,并在直流系统发生故障时,通过换流过程将阻容限流元件接入,有效限制故障电流上升率和峰值,减少故障开断所需时间。基于所提拓扑设计了6 kV/4.2 kA的直流断路器模型,在PSCAD/EMTDC中进行仿真,并与现有拓扑进行对比分析。仿真结果表明:所设计断路器可针对直流系统不同的运行状态,按照不同的控制策略顺利完成对直流电流的开断,并且在开断速度、限流能力和金属氧化物避雷器(metal oxide arrester,MOA)耗能方面均具有一定优势。
文摘针对传统最大似然波达方向(maximum likelihood direction of arrival,ML-DOA)估计存在计算量大、估计精度差等问题,本文提出一种采用改进帝王蝶优化算法(improved monarch butterfly optimization algorithm,IMBO)的ML-DOA估计方法。IMBO算法通过精英反向学习策略对初始帝王蝶种群进行优化,得到适应度值较优的初始帝王蝶个体,进而能够改善帝王蝶种群的多样性;引入差分进化算法启发的变异操作以及自适应策略对帝王蝶个体的寻优方式进行改进,扩大了算法的搜索空间;引入了高斯-柯西变异算子,自适应调整变异步长,避免算法陷入局部最优。将IMBO应用于ML-DOA,实验表明,与传统的DOA估计算法相比,在不同信源数目、信噪比以及种群数量下,本文提出的算法收敛性能更好,均方根误差更低,运算量更小。