In a post-disaster environment characterized by frequent interruptions in communication links,traditional wireless communication networks are ineffective.Although the“store-carry-forward”mechanism characteristic of ...In a post-disaster environment characterized by frequent interruptions in communication links,traditional wireless communication networks are ineffective.Although the“store-carry-forward”mechanism characteristic of Delay Tolerant Networks(DTNs)can transmit data from Internet of things devices to more reliable base stations or data centres,it also suffers from inefficient data transmission and excessive transmission delays.To address these challenges,we propose an intelligent routing strategy based on node sociability for post-disaster emergency network scenarios.First,we introduce an intelligent routing strategy based on node intimacy,which selects more suitable relay nodes and assigns the corresponding number of message copies based on comprehensive utility values.Second,we present an intelligent routing strategy based on geographical location of nodes to forward message replicas secondarily based on transmission utility values.Finally,experiments demonstrate the effectiveness of our proposed algorithm in terms of message delivery rate,network cost ratio and average transmission delay.展开更多
Photonic neural networks have garnered significant attention in recent years due to their ultra-high computational speed,broad bandwidth,and parallel processing capabilities.However,compared to conventional electronic...Photonic neural networks have garnered significant attention in recent years due to their ultra-high computational speed,broad bandwidth,and parallel processing capabilities.However,compared to conventional electronic nonlinear activa-tion function(NAF),progress on efficient and easily implementable optical nonlinear activation function(ONAF)was barely reported.To address this issue,we proposed a programmable,low-loss ONAF device based on a silicon micro-ring resonator capped with the Antimony selenide(Sb_(2)Se_(3))thin films,and with indium tin oxide(ITO)used as the microheater.Leveraging our self-developed phase-transformation kinetic and optical models,we successfully simulated the phase-transition behavior of Sb_(2)Se_(3)and three different ONAFs—ELU,ReLU,and radial basis function(RBF)were achieved according to discernible optical responses of proposed devices under different phase-change extents.Classification results from the Fashion MNIST dataset demonstrated that these ONAFs can be considered as appropriate substitutes for traditional NAF.This indicated the bright prospect of the proposed device for nonlinear activation function in future photonic neural networks.展开更多
In this paper,we investigate a multi-UAV aided NOMA communication system,where multiple UAV-mounted aerial base stations are employed to serve ground users in the downlink NOMA communication,and each UAV serves its as...In this paper,we investigate a multi-UAV aided NOMA communication system,where multiple UAV-mounted aerial base stations are employed to serve ground users in the downlink NOMA communication,and each UAV serves its associated users on its own bandwidth.We aim at maximizing the overall common throughput in a finite time period.Such a problem is a typical mixed integer nonlinear problem,which involves both continuous-variable and combinatorial optimizations.To efficiently solve this problem,we propose a two-layer algorithm,which separately tackles continuous-variable and combinatorial optimization.Specifically,in the inner layer given one user association scheme,subproblems of bandwidth allocation,power allocation and trajectory design are solved based on alternating optimization.In the outer layer,a small number of candidate user association schemes are generated from an initial scheme and the best solution can be determined by comparing all the candidate schemes.In particular,a clustering algorithm based on K-means is applied to produce all candidate user association schemes,the successive convex optimization technique is adopted in the power allocation subproblem and a logistic function approximation approach is employed in the trajectory design subproblem.Simulation results show that the proposed NOMA scheme outperforms three baseline schemes in downlink common throughput,including one solution proposed in an existing literature.展开更多
Identifying key nodes in complex networks is crucial for understanding and controlling their dynamics. Traditional centrality measures often fall short in capturing the multifaceted roles of nodes within these network...Identifying key nodes in complex networks is crucial for understanding and controlling their dynamics. Traditional centrality measures often fall short in capturing the multifaceted roles of nodes within these networks. The Page Rank algorithm, widely recognized for ranking web pages, offers a more nuanced approach by considering the importance of connected nodes. However, existing methods generally overlook the geometric properties of networks, which can provide additional insights into their structure and functionality. In this paper, we propose a novel method named Curv-Page Rank(C-PR), which integrates network curvature and Page Rank to identify influential nodes in complex networks. By leveraging the geometric insights provided by curvature alongside structural properties, C-PR offers a more comprehensive measure of a node's influence. Our approach is particularly effective in networks with community structures, where it excels at pinpointing bridge nodes critical for maintaining connectivity and facilitating information flow. We validate the effectiveness of C-PR through extensive experiments. The results demonstrate that C-PR outperforms traditional centrality-based and Page Rank methods in identifying critical nodes. Our findings offer fresh insights into the structural importance of nodes across diverse network configurations, highlighting the potential of incorporating geometric properties into network analysis.展开更多
Objectives:Teachers are facing unprecedented new challenges leading them to face an increasing number of tasks that are not part of their job,as well as having to cope with the additional skills acquisition that comes...Objectives:Teachers are facing unprecedented new challenges leading them to face an increasing number of tasks that are not part of their job,as well as having to cope with the additional skills acquisition that comes with non-traditional forms of teaching and learning,and increased work pressure leading to an increase in the rate of teachers leaving the profession.Therefore,this study aims to explore the mechanism of the career calling on job burnout through career adaptability and work engagement.Methods:This study conducted a cross-sectional survey of 465 primary and secondary school teachers(PSST)in China's Mainland from the perspective of work adjustment and used structural equation modeling(SEM)to examine the mediating roles of career adaptability and work engagement in the relationship between teachers’career calling and job burnout.Results:The results show that PSSTs are above average in career calling,career adaptability,and work engagement,while job burnout is below average.A significant positive or negative correlation exists between career calling,career adaptability,work engagement,and job burnout.The result of path analysis indicates that career adaptability and work engagement exert an indirect influence on the job burnout of PSST through three paths:namely,the independent intermediary role of career adaptability(EV=−0.144),the independent intermediary role of work engagement(EV=0.172)and the chain intermediary role of the two(EV=0.176).Conclusion:This study emphasizes the importance of career adaptability and work engagement in teacher development in regulating career calling and job burnout.Therefore,on the one hand,we think that if managers want to reduce teachers’job burnout,they need to pay more attention to teachers’career adaptability and work engagement,rather than relying solely on teachers’career calling.On the other hand,it is to remind teachers not to rely on their adjustment to adapt to the work,but also to need outside help as much as possible.展开更多
Although it has a significant advantage in gain properties,the lack of selective etching processes hinders ZnO lasing in on-chip applications.Herein,the circular ZnO microdisk pivoted on Si substrate is fabricated thr...Although it has a significant advantage in gain properties,the lack of selective etching processes hinders ZnO lasing in on-chip applications.Herein,the circular ZnO microdisk pivoted on Si substrate is fabricated through depositing ZnO on patterned silicon on an insulator(SOI)substrate.The cavity structure,morphology,and photoluminescence(PL)properties are studied systematically.The cavity shows a well-defined circular structure with oxygen vacancies.Under the synergistic action of surface tension and stress,the ZnO microdisk shows a unique toroid structure with a high sidewall surface finish.The ZnO microcavity(8μm in diameter)shows optically pumped whispering gallery modes(WGMs)lasing in the ultraviolet region with a Q factor exceeding 1300.More interestingly,the quality of the toroid ZnO microdisk cavity is high enough to support the bandgap renormalization(BGR)phenomenon.With the increasing pumping power,the lasing spectra will be modulated.The lasing spectrum undergoes a Burstein-Moss(BM)effect-induced blueshift and an electron-hole plasma(EHP)effect-induced redshift.展开更多
Various chemical irrigants and drugs have been employed for intra-canal disinfection in root canal therapy(RCT).However,due to the complexity of root canal anatomy,many drugs still exhibit poor penetrability and antib...Various chemical irrigants and drugs have been employed for intra-canal disinfection in root canal therapy(RCT).However,due to the complexity of root canal anatomy,many drugs still exhibit poor penetrability and antibiotic resistance,leading to suboptimal treatment outcomes.Thus,it is challenging to remove the organic biofilms from root canals.In recent years,light-responsive therapy,with deeper tissue penetration than traditional treatments,has emerged as an effective RCT modality.Herein,this review summarizes the recent development of light-responsive nanomaterials for biofilm removal in RCT.The light-responsive nanomaterials and the corresponding therapeutic methods in RCT,including photodynamic therapy(PDT),photothermal therapy(PTT),and laser-activated therapy,are highlighted.Finally,the challenges that light-responsive nanomaterials and treatment modalities will encounter to conquer the biofilm in future RCT are discussed.This review is believed to significantly accelerate the future development of light-responsive nanomaterials for RCT from bench to bedside.展开更多
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe...Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target.展开更多
A novel suppression method of the phase noise is proposed to reduce the negative impacts of phase noise in coherent optical orthogonal frequency division multiplexing(CO-OFDM)systems.The method integrates the sub-symb...A novel suppression method of the phase noise is proposed to reduce the negative impacts of phase noise in coherent optical orthogonal frequency division multiplexing(CO-OFDM)systems.The method integrates the sub-symbol second-order polynomial interpolation(SSPI)with cubature Kalman filter(CKF)to improve the precision and effectiveness of the data processing through using a three-stage processing approach of phase noise.First of all,the phase noise values in OFDM symbols are calculated by using pilot symbols.Then,second-order Newton interpolation(SNI)is used in second-order interpolation to acquire precise noise estimation.Afterwards,every OFDM symbol is partitioned into several sub-symbols,and second-order polynomial interpolation(SPI)is utilized in the time domain to enhance suppression accuracy and time resolution.Ultimately,CKF is employed to suppress the residual phase noise.The simulation results show that this method significantly suppresses the impact of the phase noise on the system,and the error floors can be decreased at the condition of 16 quadrature amplitude modulation(16QAM)and 32QAM.The proposed method can greatly improve the CO-OFDM system's ability to tolerate the wider laser linewidth.This method,compared to the linear interpolation sub-symbol common phase error compensation(LI-SCPEC)and Lagrange interpolation and extended Kalman filter(LRI-EKF)algorithms,has superior suppression effect.展开更多
Cognitive enhancement is essential for maintaining the quality of life in healthy individuals and improving the ability of those with mental impairments.In recent years,noninvasive neuromodulation techniques(such as t...Cognitive enhancement is essential for maintaining the quality of life in healthy individuals and improving the ability of those with mental impairments.In recent years,noninvasive neuromodulation techniques(such as transcranial magnetic stimulation,transcranial direct-current stimulation,and transcranial ultrasound stimulation)have shown significant potential in enhancing cognitive functions[1,2].Existing technologies are limited mainly to superficial cortical regions,with limited efficacy in targeting deep brain areas and inadequate methods for evaluating their modulatory effects.Selecting stimulation parameters(such as locus,depth,and intensity)and assessing the impact of neuromodulation remains incompletely understood.展开更多
Permanent magnet synchronous motor(PMSM),known for their compact size and high-power density,is widely used in fields such as electric vehicles and servo drives.However,traditional PID control methods for PMSM cannot ...Permanent magnet synchronous motor(PMSM),known for their compact size and high-power density,is widely used in fields such as electric vehicles and servo drives.However,traditional PID control methods for PMSM cannot dynamically adjust parameters according to varying operating conditions.To address this issue,this paper proposes a PID control method based on a radial basis function(RBF)neural network,which adaptively tunes the PID controller parameters.First,an offline RBF neural network with optimal structural parameters is trained using the current and speed data of the PMSM,and then employed to construct the RBF-PID controller.During online training,the Jacobian information calculated via the RBF neural network is used to adaptively adjust the PID parameters.Simultaneously,the structural parameters of the RBF network are updated in reverse based on the error between the predicted and reference speed values.Finally,numerical simulations and experiments in the context of electric vehicle drive control show that the maximum speed errors of the SMC controller and the RBF-PID controller are 1.97 km/h and 0.17 km/h,respectively.Moreover,the RBF-PID controller outperforms both the SMC and traditional PID controllers in handling sudden speed changes.展开更多
Dispersion characteristics of magnonic crystals have attracted considerable attention because of the potential applications for spin-wave devices.In this work,we investigated the strain-manipulated dispersion characte...Dispersion characteristics of magnonic crystals have attracted considerable attention because of the potential applications for spin-wave devices.In this work,we investigated the strain-manipulated dispersion characteristics of magnonic crystals with Dzyaloshinskii–Moriya interaction(DMI)and discussed the potential applications in spin-wave devices.Here,the ground states and stabilities of the magnonic crystals were investigated.Then,the strain-manipulated dispersion characteristics of the magnonic crystals based on domains and skyrmions were studied.The simulation results indicated that,the applied strain could manipulate the band widths and the positions of the allowed frequency bands.Finally,the realization of magnonic crystal heterojunctions and potential applications in spin-wave devices,such as filters,diodes,and transistors based on strain-manipulated magnonic crystals were proposed.Our research provides a theoretical foundation for designing tunable spin-wave devices based on strain-manipulated magnonic crystals with DMI.展开更多
The Global Positioning System(GPS)plays an indispensable role in the control of Unmanned Aerial Vehicle(UAV).However,the civilian GPS signals,transmitted over the air without any encryption,are vulnerable to spoofing ...The Global Positioning System(GPS)plays an indispensable role in the control of Unmanned Aerial Vehicle(UAV).However,the civilian GPS signals,transmitted over the air without any encryption,are vulnerable to spoofing attacks,which further guides the UAV on deviated positions or trajectories.To counter the GPS,,m spoofing on UAV system and to detect the position/trajectory anomaly in real time,a motion state vector based stack long short-term memory trajectory prediction scheme is firstly proposed,leveraging the temporal and spatial features of UAV kinematics.Based on the predicted results,an ensemble voting-based trajectory anomaly detection scheme is proposed to detect the position anomalies in real time with the information of motion state sequences.The proposed prediction-based trajectory anomaly detection scheme outperforms the existing offline detection schemes designed for fixed trajectories.Software In The Loop(SITL)based online prediction and online anomaly detection are demonstrated with random 3D flight trajectories.Results show that the coefficient of determination(R^(2))and Root Mean Square Error(RMSE)of the prediction scheme can reach 0.996 and 3.467,respectively.The accuracy,recall,and F1-score of the proposed anomaly detection scheme can reach 0.984,0.988,and 0.983,respectively,which outperform deep ensemble learning,LSTM-based classifier,machine learning classifier and GA-XGBoost based schemes.Moreover,results show that compared with LSTM-based classifier,the average duration(from the moment starting an attack to the moment the attack being detected)and distance of the proposed scheme are reduced by 24.4%and 19.5%,respectively.展开更多
Renormalization group analysis has been proposed to eliminate secular terms in perturbation solutions of differential equations and thus expand the domain of their validity.Here we extend the method to treat periodic ...Renormalization group analysis has been proposed to eliminate secular terms in perturbation solutions of differential equations and thus expand the domain of their validity.Here we extend the method to treat periodic orbits or limit cycles.Interesting normal forms could be derived through a generalization of the concept'resonance',which offers nontrivial analytic approximations.Compared with traditional techniques such as multi-scale methods,the current scheme proceeds in a very straightforward and simple way,delivering not only the period and the amplitude but also the transient path to limit cycles.The method is demonstrated with several examples including the Duffing oscillator,van der Pol equation and Lorenz equation.The obtained solutions match well with numerical results and with those derived by traditional analytic methods.展开更多
BACKGROUND Stomal complications though small in early postoperative period,but poses significant morbidity,therapeutic challenge,delay in adjuvant treatment and sometimes even leads to mortality.Predictive model for e...BACKGROUND Stomal complications though small in early postoperative period,but poses significant morbidity,therapeutic challenge,delay in adjuvant treatment and sometimes even leads to mortality.Predictive model for early detection of stomal complications is important to improve the outcome.A model including patients and disease related factors,intraoperative surgical techniques and biochemical markers would be a better determinant to anticipate early stomal complications.Incorporation of emerging tools and technology such as artificial intelligence(AI),will further improve the prediction.AIM To identify various risk factors and models for prediction of early post operative stomal complications in colorectal cancer(CRC)surgery.METHODS Published literatures on early postoperative stomal complications in CRC surgery were systematically reviewed between 1995 and 2024 from online search engines PubMed and MEDLINE.RESULTS Twenty-four observational studies focused on identifying various risk factors for early post operative stomal complications in CRC surgery were analyzed.Stomal complications in CRC are influenced by several factors such as disease factors,patient-specific characteristics,and surgical techniques.There are some biomarkers and tools loke AI which may play significant roles in early detection.CONCLUSION Careful analysis of these factors,changes in biochemical parameters,and application of AI,a predictive model for stomal complications can be generated,to help in early detection,prompt action to achieve better outcomes.展开更多
BACKGROUND 2D-echocardiography(2DE)has been the primary imaging modality in children with Kawasaki disease(KD)to assess coronary arteries.AIM To report the presence and implications of incidental congenital coronary a...BACKGROUND 2D-echocardiography(2DE)has been the primary imaging modality in children with Kawasaki disease(KD)to assess coronary arteries.AIM To report the presence and implications of incidental congenital coronary artery anomalies that had been misinterpreted as coronary artery abnormalities(CAAs)on 2DE.METHODS Records of children diagnosed with KD,who underwent computed tomography coronary angiography(CTCA)at our center between 2013-2023 were reviewed.We identified 3 children with congenital coronary artery anomalies in this cohort on CTCA.Findings of CTCA and 2DE were compared in these 3 children.RESULTS Of the 241 patients with KD who underwent CTCA,3(1.24%)had congenital coronary artery anomalies on CTCA detected incidentally.In all 3 patients,baseline 2DE had identified CAAs.CTCA was then performed for detailed evaluation as per our unit protocol.One(11-year-boy)amongst the 3 patients had complete KD,while the other two(3.3-year-boy;4-month-girl)had incomplete KD.CTCA revealed separate origins of left anterior descending artery and left circumflex from left sinus[misinterpreted as dilated left main coronary artery(LCA)on 2DE],single coronary artery(interpreted as dilated LCA on 2DE)and dilated right coronary artery on 2DE in case of anomalous origin of LCA from the main pulmonary artery.The latter one was subsequently operated upon.CONCLUSION CTCA is essential for detailed assessment of coronary arteries in children with KD especially in cases where there is suspicion of congenital coronary artery anomalies.Relying solely on 2DE may not be sufficient in such cases,and findings from CTCA can significantly impact therapeutic decision-making.展开更多
Inflammatory bowel disease(IBD)is a group of chronic disorders that cause relapsing inflammation in the gastrointestinal tract(GIT).It results either from gene-environment interactions or as a monogenic disease result...Inflammatory bowel disease(IBD)is a group of chronic disorders that cause relapsing inflammation in the gastrointestinal tract(GIT).It results either from gene-environment interactions or as a monogenic disease resulting from pa-thogenic mutations causing impairment in the protective mechanism of the GIT.Around 10%-15%of patients with very early onset IBDs may have an underlying monogenic condition.Monogenic IBD is very different from complex forms of polygenic IBD in the underlying molecular basis of uncontrolled intestinal inflam-mation,age of onset,extraintestinal comorbidities as well as treatment modality.An in-depth understanding of this distinct form of IBD is essential for deciding an appropriate therapeutic approach as well as prognostication.In this review,we aim to discuss about the epidemiology,clinical presentation,diagnostic approach,therapeutic challenges and latest advances in patients with monogenic IBD.展开更多
Multi-band optical networks are a potential technology for increasing network capacity.However,the strong interference and non-uniformity between wavelengths in multi-band optical networks have become a bottleneck res...Multi-band optical networks are a potential technology for increasing network capacity.However,the strong interference and non-uniformity between wavelengths in multi-band optical networks have become a bottleneck restricting the transmission capacity of multi-band optical networks.To overcome these challenges,it is particularly important to implement optical power optimization targeting wavelength differences.Therefore,based on the generalized Gaussian noise model,we first formulate an optimization model for the problems of routing,modulation format,wavelength,and power allocation in C+L+S multi-band optical networks.Our objective function is to maximize the average link capacity of the network while ensuring that the Optical Signal-to-Noise(OSNR)threshold of the service request is not exceeded.Next,we propose a NonLinear Interferenceaware(NLI-aware)routing,modulation format,wavelength,and power allocation algorithm.Finally,we conduct simulations under different test conditions.The simulation results indicate that our algorithm can effectively reduce the blocking probability by 23.5%and improve the average link capacity by 3.78%in C+L+S multi-band optical networks.展开更多
With the rapid development of generative artificial intelligence technologies,represented by large language models,university-level computer science education is undergoing a critical transition-from knowledge-based i...With the rapid development of generative artificial intelligence technologies,represented by large language models,university-level computer science education is undergoing a critical transition-from knowledge-based instruction to competency-oriented teaching.A postgraduate student competency evaluation model can serve as a framework to organize and guide both teaching and research activities at the postgraduate level.A number of relevant research efforts have already been conducted in this area.Graduate education plays a vital role not only as a continuation and enhancement of undergraduate education but also as essential preparation for future research endeavors.An analysis of the acceptance of competency evaluation models refers to the assessment of how various stakeholders perceive the importance of different components within the model.Investigating the degree of acceptance among diverse groups-such as current undergraduate students,current postgraduate students,graduates with less than three years of work experience,and those with more than three years of work experience-can offer valuable insights for improving and optimizing postgraduate education and training practices.展开更多
A Ka-band wideband microstrip-to-microstrip(MS-to-MS)vialess vertical transition on slotline multimode resonator(MMR)is presented.The proposed transition mainly consists of a slotline MMR on the common ground plane,an...A Ka-band wideband microstrip-to-microstrip(MS-to-MS)vialess vertical transition on slotline multimode resonator(MMR)is presented.The proposed transition mainly consists of a slotline MMR on the common ground plane,and two microstrip(MS)lines facing each other at the top and third layers in the four-layered liquid crystal polymer(LCP)substrate.In order to improve the bandwidth of the proposed transition,a U-shaped branch is added to the top-and third-layer MS lines,separately.The slotline MMR can be properly excited by setting the position of the U-shaped branch line.As such,a three-pole wideband vertical transition is obtained,which shows a good transmission performance over a wide frequency range of 29.27-39.95 GHz.The three-pole wideband vertical transition based on multilayer LCP substrate is designed,fabricated,and measured.Test results indicate that a wide frequency range of 26.8436.26 GHz can be obtained with return loss better than-10dB and insertion loss less than-3dB.展开更多
基金funded by the Researchers Supporting Project Number RSPD2024R681,King Saud University,Riyadh,Saudi Arabia.
文摘In a post-disaster environment characterized by frequent interruptions in communication links,traditional wireless communication networks are ineffective.Although the“store-carry-forward”mechanism characteristic of Delay Tolerant Networks(DTNs)can transmit data from Internet of things devices to more reliable base stations or data centres,it also suffers from inefficient data transmission and excessive transmission delays.To address these challenges,we propose an intelligent routing strategy based on node sociability for post-disaster emergency network scenarios.First,we introduce an intelligent routing strategy based on node intimacy,which selects more suitable relay nodes and assigns the corresponding number of message copies based on comprehensive utility values.Second,we present an intelligent routing strategy based on geographical location of nodes to forward message replicas secondarily based on transmission utility values.Finally,experiments demonstrate the effectiveness of our proposed algorithm in terms of message delivery rate,network cost ratio and average transmission delay.
基金supported by the National Natural Science Foundation of China(Grant Nos.62104114,62404111)Natural Science Foundation of Jiangsu Province(Grant Nos.BK20240635,BZ2021031)+4 种基金Opening Project of Advanced Integrated Circuit Package and Testing Research Center of Jiangsu Province(Grant No.NTIKFJJ202303)Natural Science Foundation of the Jiangsu Higher Education Institutions of China(Grant No.24KJB510025)Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(Grant Nos.NY223157,NY223156)Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant No.NY224140)Project funded by China Postdoctoral Science Foundation(Grant No.2023M732916).
文摘Photonic neural networks have garnered significant attention in recent years due to their ultra-high computational speed,broad bandwidth,and parallel processing capabilities.However,compared to conventional electronic nonlinear activa-tion function(NAF),progress on efficient and easily implementable optical nonlinear activation function(ONAF)was barely reported.To address this issue,we proposed a programmable,low-loss ONAF device based on a silicon micro-ring resonator capped with the Antimony selenide(Sb_(2)Se_(3))thin films,and with indium tin oxide(ITO)used as the microheater.Leveraging our self-developed phase-transformation kinetic and optical models,we successfully simulated the phase-transition behavior of Sb_(2)Se_(3)and three different ONAFs—ELU,ReLU,and radial basis function(RBF)were achieved according to discernible optical responses of proposed devices under different phase-change extents.Classification results from the Fashion MNIST dataset demonstrated that these ONAFs can be considered as appropriate substitutes for traditional NAF.This indicated the bright prospect of the proposed device for nonlinear activation function in future photonic neural networks.
基金supported by Beijing Natural Science Fund–Haidian Original Innovation Joint Fund(L232040 and L232045).
文摘In this paper,we investigate a multi-UAV aided NOMA communication system,where multiple UAV-mounted aerial base stations are employed to serve ground users in the downlink NOMA communication,and each UAV serves its associated users on its own bandwidth.We aim at maximizing the overall common throughput in a finite time period.Such a problem is a typical mixed integer nonlinear problem,which involves both continuous-variable and combinatorial optimizations.To efficiently solve this problem,we propose a two-layer algorithm,which separately tackles continuous-variable and combinatorial optimization.Specifically,in the inner layer given one user association scheme,subproblems of bandwidth allocation,power allocation and trajectory design are solved based on alternating optimization.In the outer layer,a small number of candidate user association schemes are generated from an initial scheme and the best solution can be determined by comparing all the candidate schemes.In particular,a clustering algorithm based on K-means is applied to produce all candidate user association schemes,the successive convex optimization technique is adopted in the power allocation subproblem and a logistic function approximation approach is employed in the trajectory design subproblem.Simulation results show that the proposed NOMA scheme outperforms three baseline schemes in downlink common throughput,including one solution proposed in an existing literature.
基金Project partially supported by the National Natural Science Foundation of China (Grant Nos. 61672298 and 62373197)the Major Project of Philosophy and Social Science Research in Colleges and Universities in Jiangsu Province,China (Grant No. 2018SJZDI142)the Postgraduate Research & Practice Innovation Program of Jiangsu Province,China (Grant No. KYCX23 1045)。
文摘Identifying key nodes in complex networks is crucial for understanding and controlling their dynamics. Traditional centrality measures often fall short in capturing the multifaceted roles of nodes within these networks. The Page Rank algorithm, widely recognized for ranking web pages, offers a more nuanced approach by considering the importance of connected nodes. However, existing methods generally overlook the geometric properties of networks, which can provide additional insights into their structure and functionality. In this paper, we propose a novel method named Curv-Page Rank(C-PR), which integrates network curvature and Page Rank to identify influential nodes in complex networks. By leveraging the geometric insights provided by curvature alongside structural properties, C-PR offers a more comprehensive measure of a node's influence. Our approach is particularly effective in networks with community structures, where it excels at pinpointing bridge nodes critical for maintaining connectivity and facilitating information flow. We validate the effectiveness of C-PR through extensive experiments. The results demonstrate that C-PR outperforms traditional centrality-based and Page Rank methods in identifying critical nodes. Our findings offer fresh insights into the structural importance of nodes across diverse network configurations, highlighting the potential of incorporating geometric properties into network analysis.
基金funded by Humanities and Social Sciences Foundation and Natural Science Foundation of Nanjing University of Posts and Telecommunications(NYY222055,NY224176)General Subject of Educational Science Planning in Jiangsu Province(C/2024/01/76)National Natural Science Foundation of China(62307025).
文摘Objectives:Teachers are facing unprecedented new challenges leading them to face an increasing number of tasks that are not part of their job,as well as having to cope with the additional skills acquisition that comes with non-traditional forms of teaching and learning,and increased work pressure leading to an increase in the rate of teachers leaving the profession.Therefore,this study aims to explore the mechanism of the career calling on job burnout through career adaptability and work engagement.Methods:This study conducted a cross-sectional survey of 465 primary and secondary school teachers(PSST)in China's Mainland from the perspective of work adjustment and used structural equation modeling(SEM)to examine the mediating roles of career adaptability and work engagement in the relationship between teachers’career calling and job burnout.Results:The results show that PSSTs are above average in career calling,career adaptability,and work engagement,while job burnout is below average.A significant positive or negative correlation exists between career calling,career adaptability,work engagement,and job burnout.The result of path analysis indicates that career adaptability and work engagement exert an indirect influence on the job burnout of PSST through three paths:namely,the independent intermediary role of career adaptability(EV=−0.144),the independent intermediary role of work engagement(EV=0.172)and the chain intermediary role of the two(EV=0.176).Conclusion:This study emphasizes the importance of career adaptability and work engagement in teacher development in regulating career calling and job burnout.Therefore,on the one hand,we think that if managers want to reduce teachers’job burnout,they need to pay more attention to teachers’career adaptability and work engagement,rather than relying solely on teachers’career calling.On the other hand,it is to remind teachers not to rely on their adjustment to adapt to the work,but also to need outside help as much as possible.
文摘Although it has a significant advantage in gain properties,the lack of selective etching processes hinders ZnO lasing in on-chip applications.Herein,the circular ZnO microdisk pivoted on Si substrate is fabricated through depositing ZnO on patterned silicon on an insulator(SOI)substrate.The cavity structure,morphology,and photoluminescence(PL)properties are studied systematically.The cavity shows a well-defined circular structure with oxygen vacancies.Under the synergistic action of surface tension and stress,the ZnO microdisk shows a unique toroid structure with a high sidewall surface finish.The ZnO microcavity(8μm in diameter)shows optically pumped whispering gallery modes(WGMs)lasing in the ultraviolet region with a Q factor exceeding 1300.More interestingly,the quality of the toroid ZnO microdisk cavity is high enough to support the bandgap renormalization(BGR)phenomenon.With the increasing pumping power,the lasing spectra will be modulated.The lasing spectrum undergoes a Burstein-Moss(BM)effect-induced blueshift and an electron-hole plasma(EHP)effect-induced redshift.
基金supported by the Natural Science Foundation of Jiangsu Province(No.BK20200092)。
文摘Various chemical irrigants and drugs have been employed for intra-canal disinfection in root canal therapy(RCT).However,due to the complexity of root canal anatomy,many drugs still exhibit poor penetrability and antibiotic resistance,leading to suboptimal treatment outcomes.Thus,it is challenging to remove the organic biofilms from root canals.In recent years,light-responsive therapy,with deeper tissue penetration than traditional treatments,has emerged as an effective RCT modality.Herein,this review summarizes the recent development of light-responsive nanomaterials for biofilm removal in RCT.The light-responsive nanomaterials and the corresponding therapeutic methods in RCT,including photodynamic therapy(PDT),photothermal therapy(PTT),and laser-activated therapy,are highlighted.Finally,the challenges that light-responsive nanomaterials and treatment modalities will encounter to conquer the biofilm in future RCT are discussed.This review is believed to significantly accelerate the future development of light-responsive nanomaterials for RCT from bench to bedside.
基金Supported by the Key Laboratory Fund for Equipment Pre-Research(6142207210202)。
文摘Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target.
基金supported by the National Natural Science Foundation of China(Nos.U21A20447 and 61971079)。
文摘A novel suppression method of the phase noise is proposed to reduce the negative impacts of phase noise in coherent optical orthogonal frequency division multiplexing(CO-OFDM)systems.The method integrates the sub-symbol second-order polynomial interpolation(SSPI)with cubature Kalman filter(CKF)to improve the precision and effectiveness of the data processing through using a three-stage processing approach of phase noise.First of all,the phase noise values in OFDM symbols are calculated by using pilot symbols.Then,second-order Newton interpolation(SNI)is used in second-order interpolation to acquire precise noise estimation.Afterwards,every OFDM symbol is partitioned into several sub-symbols,and second-order polynomial interpolation(SPI)is utilized in the time domain to enhance suppression accuracy and time resolution.Ultimately,CKF is employed to suppress the residual phase noise.The simulation results show that this method significantly suppresses the impact of the phase noise on the system,and the error floors can be decreased at the condition of 16 quadrature amplitude modulation(16QAM)and 32QAM.The proposed method can greatly improve the CO-OFDM system's ability to tolerate the wider laser linewidth.This method,compared to the linear interpolation sub-symbol common phase error compensation(LI-SCPEC)and Lagrange interpolation and extended Kalman filter(LRI-EKF)algorithms,has superior suppression effect.
基金supported by the National Natural Science Foundation of China(82172018 and 62333002).
文摘Cognitive enhancement is essential for maintaining the quality of life in healthy individuals and improving the ability of those with mental impairments.In recent years,noninvasive neuromodulation techniques(such as transcranial magnetic stimulation,transcranial direct-current stimulation,and transcranial ultrasound stimulation)have shown significant potential in enhancing cognitive functions[1,2].Existing technologies are limited mainly to superficial cortical regions,with limited efficacy in targeting deep brain areas and inadequate methods for evaluating their modulatory effects.Selecting stimulation parameters(such as locus,depth,and intensity)and assessing the impact of neuromodulation remains incompletely understood.
文摘Permanent magnet synchronous motor(PMSM),known for their compact size and high-power density,is widely used in fields such as electric vehicles and servo drives.However,traditional PID control methods for PMSM cannot dynamically adjust parameters according to varying operating conditions.To address this issue,this paper proposes a PID control method based on a radial basis function(RBF)neural network,which adaptively tunes the PID controller parameters.First,an offline RBF neural network with optimal structural parameters is trained using the current and speed data of the PMSM,and then employed to construct the RBF-PID controller.During online training,the Jacobian information calculated via the RBF neural network is used to adaptively adjust the PID parameters.Simultaneously,the structural parameters of the RBF network are updated in reverse based on the error between the predicted and reference speed values.Finally,numerical simulations and experiments in the context of electric vehicle drive control show that the maximum speed errors of the SMC controller and the RBF-PID controller are 1.97 km/h and 0.17 km/h,respectively.Moreover,the RBF-PID controller outperforms both the SMC and traditional PID controllers in handling sudden speed changes.
文摘Dispersion characteristics of magnonic crystals have attracted considerable attention because of the potential applications for spin-wave devices.In this work,we investigated the strain-manipulated dispersion characteristics of magnonic crystals with Dzyaloshinskii–Moriya interaction(DMI)and discussed the potential applications in spin-wave devices.Here,the ground states and stabilities of the magnonic crystals were investigated.Then,the strain-manipulated dispersion characteristics of the magnonic crystals based on domains and skyrmions were studied.The simulation results indicated that,the applied strain could manipulate the band widths and the positions of the allowed frequency bands.Finally,the realization of magnonic crystal heterojunctions and potential applications in spin-wave devices,such as filters,diodes,and transistors based on strain-manipulated magnonic crystals were proposed.Our research provides a theoretical foundation for designing tunable spin-wave devices based on strain-manipulated magnonic crystals with DMI.
基金supported in part by the National Natural Science Foundation of China(No.62271076)in part by the Fundamental Research Funds for the Central Universities,China(No.2242022k60006).
文摘The Global Positioning System(GPS)plays an indispensable role in the control of Unmanned Aerial Vehicle(UAV).However,the civilian GPS signals,transmitted over the air without any encryption,are vulnerable to spoofing attacks,which further guides the UAV on deviated positions or trajectories.To counter the GPS,,m spoofing on UAV system and to detect the position/trajectory anomaly in real time,a motion state vector based stack long short-term memory trajectory prediction scheme is firstly proposed,leveraging the temporal and spatial features of UAV kinematics.Based on the predicted results,an ensemble voting-based trajectory anomaly detection scheme is proposed to detect the position anomalies in real time with the information of motion state sequences.The proposed prediction-based trajectory anomaly detection scheme outperforms the existing offline detection schemes designed for fixed trajectories.Software In The Loop(SITL)based online prediction and online anomaly detection are demonstrated with random 3D flight trajectories.Results show that the coefficient of determination(R^(2))and Root Mean Square Error(RMSE)of the prediction scheme can reach 0.996 and 3.467,respectively.The accuracy,recall,and F1-score of the proposed anomaly detection scheme can reach 0.984,0.988,and 0.983,respectively,which outperform deep ensemble learning,LSTM-based classifier,machine learning classifier and GA-XGBoost based schemes.Moreover,results show that compared with LSTM-based classifier,the average duration(from the moment starting an attack to the moment the attack being detected)and distance of the proposed scheme are reduced by 24.4%and 19.5%,respectively.
文摘Renormalization group analysis has been proposed to eliminate secular terms in perturbation solutions of differential equations and thus expand the domain of their validity.Here we extend the method to treat periodic orbits or limit cycles.Interesting normal forms could be derived through a generalization of the concept'resonance',which offers nontrivial analytic approximations.Compared with traditional techniques such as multi-scale methods,the current scheme proceeds in a very straightforward and simple way,delivering not only the period and the amplitude but also the transient path to limit cycles.The method is demonstrated with several examples including the Duffing oscillator,van der Pol equation and Lorenz equation.The obtained solutions match well with numerical results and with those derived by traditional analytic methods.
文摘BACKGROUND Stomal complications though small in early postoperative period,but poses significant morbidity,therapeutic challenge,delay in adjuvant treatment and sometimes even leads to mortality.Predictive model for early detection of stomal complications is important to improve the outcome.A model including patients and disease related factors,intraoperative surgical techniques and biochemical markers would be a better determinant to anticipate early stomal complications.Incorporation of emerging tools and technology such as artificial intelligence(AI),will further improve the prediction.AIM To identify various risk factors and models for prediction of early post operative stomal complications in colorectal cancer(CRC)surgery.METHODS Published literatures on early postoperative stomal complications in CRC surgery were systematically reviewed between 1995 and 2024 from online search engines PubMed and MEDLINE.RESULTS Twenty-four observational studies focused on identifying various risk factors for early post operative stomal complications in CRC surgery were analyzed.Stomal complications in CRC are influenced by several factors such as disease factors,patient-specific characteristics,and surgical techniques.There are some biomarkers and tools loke AI which may play significant roles in early detection.CONCLUSION Careful analysis of these factors,changes in biochemical parameters,and application of AI,a predictive model for stomal complications can be generated,to help in early detection,prompt action to achieve better outcomes.
文摘BACKGROUND 2D-echocardiography(2DE)has been the primary imaging modality in children with Kawasaki disease(KD)to assess coronary arteries.AIM To report the presence and implications of incidental congenital coronary artery anomalies that had been misinterpreted as coronary artery abnormalities(CAAs)on 2DE.METHODS Records of children diagnosed with KD,who underwent computed tomography coronary angiography(CTCA)at our center between 2013-2023 were reviewed.We identified 3 children with congenital coronary artery anomalies in this cohort on CTCA.Findings of CTCA and 2DE were compared in these 3 children.RESULTS Of the 241 patients with KD who underwent CTCA,3(1.24%)had congenital coronary artery anomalies on CTCA detected incidentally.In all 3 patients,baseline 2DE had identified CAAs.CTCA was then performed for detailed evaluation as per our unit protocol.One(11-year-boy)amongst the 3 patients had complete KD,while the other two(3.3-year-boy;4-month-girl)had incomplete KD.CTCA revealed separate origins of left anterior descending artery and left circumflex from left sinus[misinterpreted as dilated left main coronary artery(LCA)on 2DE],single coronary artery(interpreted as dilated LCA on 2DE)and dilated right coronary artery on 2DE in case of anomalous origin of LCA from the main pulmonary artery.The latter one was subsequently operated upon.CONCLUSION CTCA is essential for detailed assessment of coronary arteries in children with KD especially in cases where there is suspicion of congenital coronary artery anomalies.Relying solely on 2DE may not be sufficient in such cases,and findings from CTCA can significantly impact therapeutic decision-making.
文摘Inflammatory bowel disease(IBD)is a group of chronic disorders that cause relapsing inflammation in the gastrointestinal tract(GIT).It results either from gene-environment interactions or as a monogenic disease resulting from pa-thogenic mutations causing impairment in the protective mechanism of the GIT.Around 10%-15%of patients with very early onset IBDs may have an underlying monogenic condition.Monogenic IBD is very different from complex forms of polygenic IBD in the underlying molecular basis of uncontrolled intestinal inflam-mation,age of onset,extraintestinal comorbidities as well as treatment modality.An in-depth understanding of this distinct form of IBD is essential for deciding an appropriate therapeutic approach as well as prognostication.In this review,we aim to discuss about the epidemiology,clinical presentation,diagnostic approach,therapeutic challenges and latest advances in patients with monogenic IBD.
基金supported in part by the National Natural Science Foundation of China under Grants U21B2005,62201105,62331017,U24B20134,62222103,and 62025105in part by the Chongqing Municipal Education Commission under Grants KJQN202400621,KJQN202100643,and KJZDK202400608+1 种基金in part by the China Postdoctoral Science Foundation under Grant 2021M700563in part by the Chongqing Postdoctoral Funding Project under Grant 2021XM3052。
文摘Multi-band optical networks are a potential technology for increasing network capacity.However,the strong interference and non-uniformity between wavelengths in multi-band optical networks have become a bottleneck restricting the transmission capacity of multi-band optical networks.To overcome these challenges,it is particularly important to implement optical power optimization targeting wavelength differences.Therefore,based on the generalized Gaussian noise model,we first formulate an optimization model for the problems of routing,modulation format,wavelength,and power allocation in C+L+S multi-band optical networks.Our objective function is to maximize the average link capacity of the network while ensuring that the Optical Signal-to-Noise(OSNR)threshold of the service request is not exceeded.Next,we propose a NonLinear Interferenceaware(NLI-aware)routing,modulation format,wavelength,and power allocation algorithm.Finally,we conduct simulations under different test conditions.The simulation results indicate that our algorithm can effectively reduce the blocking probability by 23.5%and improve the average link capacity by 3.78%in C+L+S multi-band optical networks.
文摘With the rapid development of generative artificial intelligence technologies,represented by large language models,university-level computer science education is undergoing a critical transition-from knowledge-based instruction to competency-oriented teaching.A postgraduate student competency evaluation model can serve as a framework to organize and guide both teaching and research activities at the postgraduate level.A number of relevant research efforts have already been conducted in this area.Graduate education plays a vital role not only as a continuation and enhancement of undergraduate education but also as essential preparation for future research endeavors.An analysis of the acceptance of competency evaluation models refers to the assessment of how various stakeholders perceive the importance of different components within the model.Investigating the degree of acceptance among diverse groups-such as current undergraduate students,current postgraduate students,graduates with less than three years of work experience,and those with more than three years of work experience-can offer valuable insights for improving and optimizing postgraduate education and training practices.
基金the Shaanxi Provincial Innovation Team Project(No.2020TD-019)the Xi'an Sciences Plan Project(No.2021XJZZ0075)。
文摘A Ka-band wideband microstrip-to-microstrip(MS-to-MS)vialess vertical transition on slotline multimode resonator(MMR)is presented.The proposed transition mainly consists of a slotline MMR on the common ground plane,and two microstrip(MS)lines facing each other at the top and third layers in the four-layered liquid crystal polymer(LCP)substrate.In order to improve the bandwidth of the proposed transition,a U-shaped branch is added to the top-and third-layer MS lines,separately.The slotline MMR can be properly excited by setting the position of the U-shaped branch line.As such,a three-pole wideband vertical transition is obtained,which shows a good transmission performance over a wide frequency range of 29.27-39.95 GHz.The three-pole wideband vertical transition based on multilayer LCP substrate is designed,fabricated,and measured.Test results indicate that a wide frequency range of 26.8436.26 GHz can be obtained with return loss better than-10dB and insertion loss less than-3dB.