The mutual-interference phenomenon among multiple applications delivered as services through Cloud Services Delivery Network(CSDN)influences their QoS seriously.In order to deploy multiple applications dependably and ...The mutual-interference phenomenon among multiple applications delivered as services through Cloud Services Delivery Network(CSDN)influences their QoS seriously.In order to deploy multiple applications dependably and efficiently,we propose the Multiple Applications Co-Exist(MACE)method.MACE classifies multiple applications into different types and deploys them using isolation to some extent.Meanwhile,resource static allocation,dynamic supplement and resource reserved mechanism to minimize mutual-interference and maximize resource utilization are designed.After MACE is applied to a real large-scale CSDN and evaluated through 6-month measurement,we find that the CSDN load is more balanced,the bandwidth utilization increases by about 20%,the multiple applications'potential statistical multiplexing ratio decreases from 12% to 5%,and the number of complaint events affecting the dependability of CSDN services caused by multiple applications'mutual-interference has dropped to 0.Obviously,MACE offers a tradeoff and improvement for the dependability and efficiency goals of CSDN.展开更多
第六届IEEE International Conference on Dependable Systems and Their Applications(DSA)将于2020年1月3日~6日在美丽的哈尔滨举行。我们诚挚地邀请您投稿参与。除了regular(12页)和short papers(6页),DSA也接受Fast abstract(2页)...第六届IEEE International Conference on Dependable Systems and Their Applications(DSA)将于2020年1月3日~6日在美丽的哈尔滨举行。我们诚挚地邀请您投稿参与。除了regular(12页)和short papers(6页),DSA也接受Fast abstract(2页)的投稿。截稿日期2019年10月31日。展开更多
Quorum system is a preferable model to construct distributed access control architecture, but not all quorum system can satisfy the requirements of distributed access control architecture. Aiming at the dependable pro...Quorum system is a preferable model to construct distributed access control architecture, but not all quorum system can satisfy the requirements of distributed access control architecture. Aiming at the dependable problem of authorization server in distributed system and combining the requirements of access control, a set of criterions to select and evaluate quorum system is presented. The scheme and algorithm of constructing an authorization server system based on Paths quorum system are designed, and the integrated sys- tem performance under some servers attacked is fully analyzed. Role-based access control on the Web implemented by this scheme is introduced. Analysis shows that with certain node failure probability, the scheme not only has high dependability but also can satisfy the special requirements of distributed access control such as real-time, parallelism, and consistency of security policy.展开更多
Demand driven growth is rather a common approach in many countries in the short run. Growth in aggregate demand pushes production to higher level, increasing employment and income. But what is the case in small open e...Demand driven growth is rather a common approach in many countries in the short run. Growth in aggregate demand pushes production to higher level, increasing employment and income. But what is the case in small open economies, which are highly import dependable, service-oriented, and have to import most consumers＇ goods？ Research is focused on the case of small open economy （Montenegro）. Research will be based on statistical data for Montenegro, for period from 2000 to 2011. Data are processed in Eviews, using Least Square method to estimate equations and models. Research has shown that gross domestic product （GDP） growth in the short run, prior to global financial crisis, was achieved through growth in consumption and investment, which led to growth in import and growth in foreign debt, as consumption was financed significantly borrowing foreign financial resources. After the crisis, financial inflows dropped, leaving Montenegrin economy to struggle with increased debt （both public and private）, unfinished investment project to provide value added and low level of domestic production leading to even higher trade deficit. Future growth can be achieved only if it is driven by investments, as growth in consumption will more likely lead to higher trade deficit than production growth.展开更多
As a popular approach to dependable service oriented architecture （SOA）, a service pool collects a set of services that provide the same functionality by different service providers for achieving desired reliability...As a popular approach to dependable service oriented architecture （SOA）, a service pool collects a set of services that provide the same functionality by different service providers for achieving desired reliability. However, if the tradeoff between reliability and other important qualities, e.g., performance, has to be considered, the construction and management of a service pool become much more complex. In this paper, an automated approach to this problem is presented. Based on the investigation of service pools in the typical triangle SOA model, two challenges critical to the effectiveness and efficiency of service pools are identified, including which services should be held by a pool and what order these services are invoked in. A set of algorithms are designed to address the two challenges and then a service pool can be automatically constructed and managed for given reliability and performance requirements in polynomial time. The approach is demonstrated on a J2EE based service platform and the comparison results between different pooling algorithms are evaluated.展开更多
To fast evaluate the small probability that starts from the all-components-up state, the system hits the failed sets before returning to the all-components-up state, Important Sampling or Important Splitting is used c...To fast evaluate the small probability that starts from the all-components-up state, the system hits the failed sets before returning to the all-components-up state, Important Sampling or Important Splitting is used commonly. In this paper, a new approach distinguished from Important Sampling and Important Splitting is presented to estimate this small probability of highly dependable Markov system. This new approach achieves variance reduction through improving the estimator itself. The new estimator is derived from the integral equation describing the state transitions of Markov system. That the variance of this estimator is less than that of naive simulation at all time is proved theoretically. Two example involved reliability models with deferred repair are used to compare the methods of RB, IGBS, SB-RBS, naive simulation, and the method presented in this paper. Results show our method has the least RE.展开更多
Backfill is often employed in mining operations for ground support,with its positive impact on ground stability acknowledged in many underground mines.However,existing studies have predominantly focused only on the st...Backfill is often employed in mining operations for ground support,with its positive impact on ground stability acknowledged in many underground mines.However,existing studies have predominantly focused only on the stress development within the backfill material,leaving the influence of stope backfilling on stress distribution in surrounding rock mass and ground stability largely unexplored.Therefore,this paper presents numerical models in FLAC3D to investigate,for the first time,the time-dependent stress redistribution around a vertical backfilled stope and its implications on ground stability,considering the creep of surrounding rock mass.Using the Soft Soil constitutive model,the compressibility of backfill under large pressure was captured.It is found that the creep deformation of rock mass exercises compression on backfill and results in a less void ratio and increased modulus for fill material.The compacted backfill conversely influenced the stress distribution and ground stability of rock mass which was a combined effect of wall creep and compressibility of backfill.With the increase of time or/and creep deformation,the minimum principal stress in the rocks surrounding the backfilled stope increased towards the pre-mining stress state,while the deviatoric stress reduces leading to an increased factor of safety and improved ground stability.This improvement effect of backfill on ground stability increased with the increase of mine depth and stope height,while it is also more pronounced for the narrow stope,the backfill with a smaller compression index,and the soft rocks with a smaller viscosity coefficient.Furthermore,the results emphasize the importance of minimizing empty time and backfilling extracted stope as soon as possible for ground control.Reduction of filling gap height enhances the local stability around the roof of stope.展开更多
Spectrum-based fault localization (SBFL) generates a ranked list of suspicious elements by using the program execution spectrum, but the excessive number of elements ranked in parallel results in low localization accu...Spectrum-based fault localization (SBFL) generates a ranked list of suspicious elements by using the program execution spectrum, but the excessive number of elements ranked in parallel results in low localization accuracy. Most researchers consider intra-class dependencies to improve localization accuracy. However, some studies show that inter-class method call type faults account for more than 20%, which means such methods still have certain limitations. To solve the above problems, this paper proposes a two-phase software fault localization based on relational graph convolutional neural networks (Two-RGCNFL). Firstly, in Phase 1, the method call dependence graph (MCDG) of the program is constructed, the intra-class and inter-class dependencies in MCDG are extracted by using the relational graph convolutional neural network, and the classifier is used to identify the faulty methods. Then, the GraphSMOTE algorithm is improved to alleviate the impact of class imbalance on classification accuracy. Aiming at the problem of parallel ranking of element suspicious values in traditional SBFL technology, in Phase 2, Doc2Vec is used to learn static features, while spectrum information serves as dynamic features. A RankNet model based on siamese multi-layer perceptron is constructed to score and rank statements in the faulty method. This work conducts experiments on 5 real projects of Defects4J benchmark. Experimental results show that, compared with the traditional SBFL technique and two baseline methods, our approach improves the Top-1 accuracy by 262.86%, 29.59% and 53.01%, respectively, which verifies the effectiveness of Two-RGCNFL. Furthermore, this work verifies the importance of inter-class dependencies through ablation experiments.展开更多
Distributed Federated Learning(DFL)technology enables participants to cooperatively train a shared model while preserving the privacy of their local datasets,making it a desirable solution for decentralized and privac...Distributed Federated Learning(DFL)technology enables participants to cooperatively train a shared model while preserving the privacy of their local datasets,making it a desirable solution for decentralized and privacy-preserving Web3 scenarios.However,DFL faces incentive and security challenges in the decentralized framework.To address these issues,this paper presents a Hierarchical Blockchain-enabled DFL(HBDFL)system,which provides a generic solution framework for the DFL-related applications.The proposed system consists of four major components,including a model contribution-based reward mechanism,a Proof of Elapsed Time and Accuracy(PoETA)consensus algorithm,a Distributed Reputation-based Verification Mechanism(DRTM)and an Accuracy-Dependent Throughput Management(ADTM)mechanism.The model contribution-based rewarding mechanism incentivizes network nodes to train models with their local datasets,while the PoETA consensus algorithm optimizes the tradeoff between the shared model accuracy and system throughput.The DRTM improves the system efficiency in consensus,and the ADTM mechanism guarantees that the throughput performance remains within a predefined range while improving the shared model accuracy.The performance of the proposed HBDFL system is evaluated by numerical simulations,with the results showing that the system improves the accuracy of the shared model while maintaining high throughput and ensuring security.展开更多
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen...In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors.展开更多
Chairs are the most common furniture in household environments,and reclining chairs specifically cater to the functional needs of the elderly.With the gradually increasing aging population,our preliminary research has...Chairs are the most common furniture in household environments,and reclining chairs specifically cater to the functional needs of the elderly.With the gradually increasing aging population,our preliminary research has revealed that current reclining chair designs often fail to align with the physical dimensions and needs of older adults.Many designs appear to prioritize technology over usability,resulting in a homogenous product landscape.Using statistical analysis and the weighted average method,an elderly-friendly reclining chair that considers height,depth,and width is designed.The final design aims to meet the psychological and physiological needs of self-care,semi-dependent,and fully dependent elderly individuals.Adhering to the“people-oriented”design philosophy and targeting“convenience and efficiency,”our ultimate goal is to create a reclining chair that helps the elderly lie down,stand up,and sit down with dignity.This innovative approach offers a new perspective for the market of aging-friendly furniture.展开更多
Existing Chinese named entity recognition(NER)research utilises 1D lexicon-based sequence labelling frameworks,which can only recognise flat entities.While lexicons serve as prior knowledge and enhance semantic inform...Existing Chinese named entity recognition(NER)research utilises 1D lexicon-based sequence labelling frameworks,which can only recognise flat entities.While lexicons serve as prior knowledge and enhance semantic information,they also pose completeness and resource requirements limitations.This paper proposes a template-based classification(TC)model to avoid lexicon issues and to identify nested entities.Template-based classification provides a template word for each entity type,which utilises contrastive learning to integrate the common characteristics among entities with the same category.Contrastive learning makes template words the centre points of their category in the vector space,thus improving generalisation ability.Additionally,TC presents a 2D tablefilling label scheme that classifies entities based on the attention distribution of template words.The proposed novel decoder algorithm enables TC recognition of both flat and nested entities simultaneously.Experimental results show that TC achieves the state-ofthe-art performance on five Chinese datasets.展开更多
Repetitive transcranial magnetic stimulation(rTMS)is a rapid and effective therapy for major depressive disorder;however,there is significant variability in therapeutic outcomes both within and across individuals,with...Repetitive transcranial magnetic stimulation(rTMS)is a rapid and effective therapy for major depressive disorder;however,there is significant variability in therapeutic outcomes both within and across individuals,with approximately 50% of patients showing no response to rTMS treatment.Many studies have personalized the stimulation parameters of rTMS(e.g.,location and intensity of stimulation)according to the anatomical and functional structure of the brain.In addition to these parameters,the internal states of the individual,such as circadian rhythm,behavior/cognition,neural oscillation,and neuroplasticity,also contribute to the variation in rTMS effects.In this review,we summarize the current literature on the interaction between rTMS and internal states.We propose two possible methods,multimodal treatment,and adaptive closed-loop treatment,to integrate patients'internal states to achieve better rTMS treatment for depression.展开更多
Artificial intelligence,especially large language models(LLMs),is reshaping how we learn,communicate,and create.These systems provide students and professionals immediate access to fluent,context-aware language that c...Artificial intelligence,especially large language models(LLMs),is reshaping how we learn,communicate,and create.These systems provide students and professionals immediate access to fluent,context-aware language that can support learning,increase productivity,and spark creativity.But what happens when their use becomes excessive?This paper explores the potential long-term consequences of over-relying on LLMs-particularly memory,critical thinking,creativity,and motivation.Drawing on research in cognitive psychology,education,neuroscience,and media studies,it argues that LLMs are best understood as cognitive prostheses:incredibly valuable when used wisely,but risky when they replace rather than support human imagination.展开更多
In this study,we performed a systematic analysis of the multiplicity dependence of hadron production at mid-rapidity(|y|<0.5),ranging from the light to the charm sector in proton-proton(pp)collisions at√s=13 TeV.T...In this study,we performed a systematic analysis of the multiplicity dependence of hadron production at mid-rapidity(|y|<0.5),ranging from the light to the charm sector in proton-proton(pp)collisions at√s=13 TeV.This study used a multi-phase transport(AMPT)model coupled with PYTHIA8 initial conditions.We investigated the baryon-to-meson and the strange-to-non-strange meson ratios varying with the charged particle density.By tuning the coalescence parameters,the AMPT model provides a reasonable description of the experimental data for the inclusive production of both light and charm hadrons,comparable to the string fragmentation model calculations with color reconnection effects.Additionally,we analyzed the relative production of hadrons by examining the self-normalized particle ratios as a function of the charged hadron density.Our findings suggest that parton evolution effects and the coalescence hadronization process in the AMPT model result in a strong flavor hierarchy in the multiplicity dependence of the baryon-to-meson ratio.Furthermore,our investigation of the p_(T) differential double ratio of the baryon-to-meson fraction between high-and low-multiplicity events revealed distinct modifications to the flavor associated baryon-to-meson ratio p_(T) shape in high-multiplicity events when comparing the coalescence hadronization model to the color reconnection model.These observations highlight the importance of understanding the hadronization process in high-energy pp collisions through comprehensive multiplicity-dependent multi-flavor analysis.展开更多
Rock slope along motorways in the Higher Himalayan terrains are prone to various types of failure.In order to effectively mitigate these failures,a thorough assessment of rock mass behavior is entailed.The present res...Rock slope along motorways in the Higher Himalayan terrains are prone to various types of failure.In order to effectively mitigate these failures,a thorough assessment of rock mass behavior is entailed.The present research employs and compares widely practiced geo-mechanical classification schemes viz.,RQD,RMR,SMR,Q-slope,and GSI.A 23 km road cut section,along Sangla to Chitkul route,in Higher Himalayan region(India)has been taken up for this work.Total of 18 locations were selected,and their slope and rockmass properties were examined.Afterwards,the most influencing parameters in RMR,SMR,and Q-Slope were evaluated through a machine learning algorithm,i.e.,Random Forest.For RMRbasic,about 83%of rock-slopes were designated in good condition and rest were of Fair quality.Evaluation of slope mass rating along all 18-locations highlighted eight-sites as partially unstable,six-sites as partially stable.Remaining four locations varied between,Very Bad to Bad slope-conditions,necessitating the installation of mechanical supports and redesign of slopes.For SMR classification,feature importance analysis revealed the predominance of F3 variable,RQD and intact rock strength.Q-Slope approach was incorporated to identify the most stable steepest angle of the examined locations.For Q-Slope rating,Jn and RQD were found to have the most influence in classification of the slopes.Three zones on the basis of GSI-scores have been identified in the study area,i.e.,A(6595),B(4555),and C(2535).This study highlights the application of multiple geomechanical classification schemes,demonstrating how each approach can complement the others.展开更多
Heroin dependence is a serious substance use disorder that not only causes great harm to physical health but also significantly affects mental health.Addicts often experience a variety of psychological problems,such a...Heroin dependence is a serious substance use disorder that not only causes great harm to physical health but also significantly affects mental health.Addicts often experience a variety of psychological problems,such as depression,anxiety,personality disorders,and cognitive impairment.In recent years the mechanisms and intervention methods related to mental health problems in heroin addicts have received widespread research attention.This article reviews the current research into mental health problems in heroin addicts in order to provide a theoretical basis for optimizing drug addiction intervention strategies.展开更多
Assessing individual differences and variability in animal movement patterns is essential to improve our understanding of the evolution and ontogeny of migratory strategies.In long-distance migratory species,fledged j...Assessing individual differences and variability in animal movement patterns is essential to improve our understanding of the evolution and ontogeny of migratory strategies.In long-distance migratory species,fledged juveniles often rely on an extremely restricted time span to learn the essential skills for survival and to prepare for migration,possibly the most risky phase of their lives.Collecting detailed information on the dynamics of the movements during the crucial pre-migratory phase is hence essential to understand the solutions developed by migratory species in different environmental contexts.Here,we used high-resolution GPS/GSM transmitters to collect information on the movement ecology of seven juvenile Montagu's Harriers(Circus pygargus)born in central Italy,investigating their early life stages,namely the post-fledging dependence period(PFDP)and the pre-migratory phase(PMP),until autumn migration.After fledging,individuals showed high variability(both in space and time)in home range size,daily distances covered(6.88±11.44 km/day),distance from the nest(1.45±2.8 km)and PFDP length(23.3±5.3 days).Residence time at the natal site significantly decreased,while time interval between revists in the natal area significantly increased,as the PFDP progressed.During the PMP,explored areas and distance from the nest(max value up to 320.8 km)varied among individuals,despite daily distances covered(27±40 km/day)and time allocation between traveling(60.7%)and foraging(39.3%)were similar across individuals.The PMP lasted 38±14 days.Land cover composition of foraging locations was mostly represented by agricultural lands(~78.2%),though habitat use differed among individuals.More than 76%of such locations were outside protected areas.This individual-based tracking study represents a novel approach that improves previous knowledge based on field studies on the early life stages of the Montagu's Harrier.High inter-individual variability in movement patterns,broad-range exploratory movements and foraging locations outside the protected area network make the application of standard conservation measures difficult,raising concerns about the long-term preservation of this vulnerable migratory species in Italy.展开更多
Due to their high dielectric constant,low melting point,and high boiling point,nitrile-based solvents exhibit significant potential in wide-temperature-range electrolytes.In this study,a wide-temperature electrolyte s...Due to their high dielectric constant,low melting point,and high boiling point,nitrile-based solvents exhibit significant potential in wide-temperature-range electrolytes.In this study,a wide-temperature electrolyte system composed of lithium bis(trifluoromethanesulfonyl)imide(LiTFSI),dimethyl carbonate(DMC),and butyronitrile(BN)in a molar ratio of 1:3:9 was designed.Using variable-temperature infrared(IR)spectroscopy with carbonyl(C=O)and cyano(C≡N)groups as IR probes,combined with molecular dynamics simulations and density functional theory calculations,the temperature-dependent evolution of the Li^(+)solvation structure and molecular dynamics were systematically investigated over the range of-45℃to 45℃.The results show that the introduction of BN not only significantly enhances the low-temperature ionic conductivity and high-temperature stability of the electrolyte,but also optimizes the solvation structure and interfacial characteristics of lithium ions through strong coordination interactions.This work provides both theoretical insights and experimental support for the design of wide-temperature electrolytes.展开更多
Understanding interlayer charge transfer is crucial for elucidating interface interactions in heterostructures.As the layer number can significantly influence the interface coupling and band alignment,the charge trans...Understanding interlayer charge transfer is crucial for elucidating interface interactions in heterostructures.As the layer number can significantly influence the interface coupling and band alignment,the charge transfer behaviors can be largely regulated.Here,we constructed two-dimensional(2D)heterostructures consisting of monolayer WS_(2)and few-layer InSe to investigate the impact of InSe thickness on exciton dynamics.We performed photoluminescence(PL)spectroscopy and lifetime measurements on pristine few-layer InSe and the heterostructures with different InSe thicknesses.For pristine InSe layers,we found a non-monotonic layer dependence on PL lifetime,which can be attributed to the interplay between the indirect-to-direct bandgap transition and surface recombination effects.For heterostructures,we demonstrated that the type I band alignment of the heterostructure facilitates electron and hole transfer from monolayer WS_(2)to InSe.As the InSe layer number increases,the reduction in conduction band minimum(CBM)enhances the driving force for charge transfer,thereby improving the transfer efficiency.Furthermore,we fabricated and characterized a WS_(2)/InSe optoelectronic device.By analyzing bias voltage dependent PL spectra,we further demonstrated that the trions in WS_(2)within the heterostructure are positively charged(X^(+)),and their emission intensity can be efficiently modulated by applying different biases.This study not only reveals the layer-dependent characteristics of band alignment and interlayer charge transfer in heterostructures but also provides valuable insights for the applications of 2D semiconductors in optoelectronic devices.展开更多
基金National Basic Research Program of China under Grant No. 2011CB302600National Natural Science Foundation of China under Grant No. 90818028,No. 61003226National Science Fund for Distinguished Young Scholars under Grant No. 60625203
文摘The mutual-interference phenomenon among multiple applications delivered as services through Cloud Services Delivery Network(CSDN)influences their QoS seriously.In order to deploy multiple applications dependably and efficiently,we propose the Multiple Applications Co-Exist(MACE)method.MACE classifies multiple applications into different types and deploys them using isolation to some extent.Meanwhile,resource static allocation,dynamic supplement and resource reserved mechanism to minimize mutual-interference and maximize resource utilization are designed.After MACE is applied to a real large-scale CSDN and evaluated through 6-month measurement,we find that the CSDN load is more balanced,the bandwidth utilization increases by about 20%,the multiple applications'potential statistical multiplexing ratio decreases from 12% to 5%,and the number of complaint events affecting the dependability of CSDN services caused by multiple applications'mutual-interference has dropped to 0.Obviously,MACE offers a tradeoff and improvement for the dependability and efficiency goals of CSDN.
文摘第六届IEEE International Conference on Dependable Systems and Their Applications(DSA)将于2020年1月3日~6日在美丽的哈尔滨举行。我们诚挚地邀请您投稿参与。除了regular(12页)和short papers(6页),DSA也接受Fast abstract(2页)的投稿。截稿日期2019年10月31日。
基金Supported by the National Natural Science Foundation of China (70771043, 60873225, 60773191)
文摘Quorum system is a preferable model to construct distributed access control architecture, but not all quorum system can satisfy the requirements of distributed access control architecture. Aiming at the dependable problem of authorization server in distributed system and combining the requirements of access control, a set of criterions to select and evaluate quorum system is presented. The scheme and algorithm of constructing an authorization server system based on Paths quorum system are designed, and the integrated sys- tem performance under some servers attacked is fully analyzed. Role-based access control on the Web implemented by this scheme is introduced. Analysis shows that with certain node failure probability, the scheme not only has high dependability but also can satisfy the special requirements of distributed access control such as real-time, parallelism, and consistency of security policy.
文摘Demand driven growth is rather a common approach in many countries in the short run. Growth in aggregate demand pushes production to higher level, increasing employment and income. But what is the case in small open economies, which are highly import dependable, service-oriented, and have to import most consumers＇ goods？ Research is focused on the case of small open economy （Montenegro）. Research will be based on statistical data for Montenegro, for period from 2000 to 2011. Data are processed in Eviews, using Least Square method to estimate equations and models. Research has shown that gross domestic product （GDP） growth in the short run, prior to global financial crisis, was achieved through growth in consumption and investment, which led to growth in import and growth in foreign debt, as consumption was financed significantly borrowing foreign financial resources. After the crisis, financial inflows dropped, leaving Montenegrin economy to struggle with increased debt （both public and private）, unfinished investment project to provide value added and low level of domestic production leading to even higher trade deficit. Future growth can be achieved only if it is driven by investments, as growth in consumption will more likely lead to higher trade deficit than production growth.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 90412011, 90612011, 60233010, and 60403030, the National Basic Research 973 Program of China under Grant No. 2002CB312003, and the IBM University Joint Study Program.
文摘As a popular approach to dependable service oriented architecture （SOA）, a service pool collects a set of services that provide the same functionality by different service providers for achieving desired reliability. However, if the tradeoff between reliability and other important qualities, e.g., performance, has to be considered, the construction and management of a service pool become much more complex. In this paper, an automated approach to this problem is presented. Based on the investigation of service pools in the typical triangle SOA model, two challenges critical to the effectiveness and efficiency of service pools are identified, including which services should be held by a pool and what order these services are invoked in. A set of algorithms are designed to address the two challenges and then a service pool can be automatically constructed and managed for given reliability and performance requirements in polynomial time. The approach is demonstrated on a J2EE based service platform and the comparison results between different pooling algorithms are evaluated.
基金supported by the National Natural Science Foundation of China(Grant No.70171029).
文摘To fast evaluate the small probability that starts from the all-components-up state, the system hits the failed sets before returning to the all-components-up state, Important Sampling or Important Splitting is used commonly. In this paper, a new approach distinguished from Important Sampling and Important Splitting is presented to estimate this small probability of highly dependable Markov system. This new approach achieves variance reduction through improving the estimator itself. The new estimator is derived from the integral equation describing the state transitions of Markov system. That the variance of this estimator is less than that of naive simulation at all time is proved theoretically. Two example involved reliability models with deferred repair are used to compare the methods of RB, IGBS, SB-RBS, naive simulation, and the method presented in this paper. Results show our method has the least RE.
基金the funding support from the National Natural Science Foundation of China(Grant Nos.52304101 and 52004206)the China Postdoctoral Science Foundation(Grant No.2023MD734215)。
文摘Backfill is often employed in mining operations for ground support,with its positive impact on ground stability acknowledged in many underground mines.However,existing studies have predominantly focused only on the stress development within the backfill material,leaving the influence of stope backfilling on stress distribution in surrounding rock mass and ground stability largely unexplored.Therefore,this paper presents numerical models in FLAC3D to investigate,for the first time,the time-dependent stress redistribution around a vertical backfilled stope and its implications on ground stability,considering the creep of surrounding rock mass.Using the Soft Soil constitutive model,the compressibility of backfill under large pressure was captured.It is found that the creep deformation of rock mass exercises compression on backfill and results in a less void ratio and increased modulus for fill material.The compacted backfill conversely influenced the stress distribution and ground stability of rock mass which was a combined effect of wall creep and compressibility of backfill.With the increase of time or/and creep deformation,the minimum principal stress in the rocks surrounding the backfilled stope increased towards the pre-mining stress state,while the deviatoric stress reduces leading to an increased factor of safety and improved ground stability.This improvement effect of backfill on ground stability increased with the increase of mine depth and stope height,while it is also more pronounced for the narrow stope,the backfill with a smaller compression index,and the soft rocks with a smaller viscosity coefficient.Furthermore,the results emphasize the importance of minimizing empty time and backfilling extracted stope as soon as possible for ground control.Reduction of filling gap height enhances the local stability around the roof of stope.
基金funded by the Youth Fund of the National Natural Science Foundation of China(Grant No.42261070).
文摘Spectrum-based fault localization (SBFL) generates a ranked list of suspicious elements by using the program execution spectrum, but the excessive number of elements ranked in parallel results in low localization accuracy. Most researchers consider intra-class dependencies to improve localization accuracy. However, some studies show that inter-class method call type faults account for more than 20%, which means such methods still have certain limitations. To solve the above problems, this paper proposes a two-phase software fault localization based on relational graph convolutional neural networks (Two-RGCNFL). Firstly, in Phase 1, the method call dependence graph (MCDG) of the program is constructed, the intra-class and inter-class dependencies in MCDG are extracted by using the relational graph convolutional neural network, and the classifier is used to identify the faulty methods. Then, the GraphSMOTE algorithm is improved to alleviate the impact of class imbalance on classification accuracy. Aiming at the problem of parallel ranking of element suspicious values in traditional SBFL technology, in Phase 2, Doc2Vec is used to learn static features, while spectrum information serves as dynamic features. A RankNet model based on siamese multi-layer perceptron is constructed to score and rank statements in the faulty method. This work conducts experiments on 5 real projects of Defects4J benchmark. Experimental results show that, compared with the traditional SBFL technique and two baseline methods, our approach improves the Top-1 accuracy by 262.86%, 29.59% and 53.01%, respectively, which verifies the effectiveness of Two-RGCNFL. Furthermore, this work verifies the importance of inter-class dependencies through ablation experiments.
文摘Distributed Federated Learning(DFL)technology enables participants to cooperatively train a shared model while preserving the privacy of their local datasets,making it a desirable solution for decentralized and privacy-preserving Web3 scenarios.However,DFL faces incentive and security challenges in the decentralized framework.To address these issues,this paper presents a Hierarchical Blockchain-enabled DFL(HBDFL)system,which provides a generic solution framework for the DFL-related applications.The proposed system consists of four major components,including a model contribution-based reward mechanism,a Proof of Elapsed Time and Accuracy(PoETA)consensus algorithm,a Distributed Reputation-based Verification Mechanism(DRTM)and an Accuracy-Dependent Throughput Management(ADTM)mechanism.The model contribution-based rewarding mechanism incentivizes network nodes to train models with their local datasets,while the PoETA consensus algorithm optimizes the tradeoff between the shared model accuracy and system throughput.The DRTM improves the system efficiency in consensus,and the ADTM mechanism guarantees that the throughput performance remains within a predefined range while improving the shared model accuracy.The performance of the proposed HBDFL system is evaluated by numerical simulations,with the results showing that the system improves the accuracy of the shared model while maintaining high throughput and ensuring security.
基金supported by the National Social Science Fundation(Grant No.21BTJ040)the Project of Outstanding Young People in University of Anhui Province(Grant Nos.2023AH020037,SLXY2024A001).
文摘In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors.
基金Chongqing University of Engineering Internal Fund Key Project in Natural Sciences:Research on Spatial Syntax Parameters and Combination Patterns of Elderly Care Centers in Urban and Rural Communities from a Multidimensional Logical Perspective(Project No:XJXM202412014)。
文摘Chairs are the most common furniture in household environments,and reclining chairs specifically cater to the functional needs of the elderly.With the gradually increasing aging population,our preliminary research has revealed that current reclining chair designs often fail to align with the physical dimensions and needs of older adults.Many designs appear to prioritize technology over usability,resulting in a homogenous product landscape.Using statistical analysis and the weighted average method,an elderly-friendly reclining chair that considers height,depth,and width is designed.The final design aims to meet the psychological and physiological needs of self-care,semi-dependent,and fully dependent elderly individuals.Adhering to the“people-oriented”design philosophy and targeting“convenience and efficiency,”our ultimate goal is to create a reclining chair that helps the elderly lie down,stand up,and sit down with dignity.This innovative approach offers a new perspective for the market of aging-friendly furniture.
基金Sichuan Provincial Science and Technology Support Program,Grant/Award Number:2023YFG0151National Natural Science Foundation of China,Grant/Award Numbers:U22B2061,U2336204。
文摘Existing Chinese named entity recognition(NER)research utilises 1D lexicon-based sequence labelling frameworks,which can only recognise flat entities.While lexicons serve as prior knowledge and enhance semantic information,they also pose completeness and resource requirements limitations.This paper proposes a template-based classification(TC)model to avoid lexicon issues and to identify nested entities.Template-based classification provides a template word for each entity type,which utilises contrastive learning to integrate the common characteristics among entities with the same category.Contrastive learning makes template words the centre points of their category in the vector space,thus improving generalisation ability.Additionally,TC presents a 2D tablefilling label scheme that classifies entities based on the attention distribution of template words.The proposed novel decoder algorithm enables TC recognition of both flat and nested entities simultaneously.Experimental results show that TC achieves the state-ofthe-art performance on five Chinese datasets.
基金supported by STI2030-Major Projects(2021ZD0204300 and 2021ZD0200800)the National Natural Science Foundation of China(82271528)the Fundamental Research Funds for the Central Universities(Peking University Medicine Fund for World's Leading Discipline or Discipline Cluster Development,BMU2022DJXK007).
文摘Repetitive transcranial magnetic stimulation(rTMS)is a rapid and effective therapy for major depressive disorder;however,there is significant variability in therapeutic outcomes both within and across individuals,with approximately 50% of patients showing no response to rTMS treatment.Many studies have personalized the stimulation parameters of rTMS(e.g.,location and intensity of stimulation)according to the anatomical and functional structure of the brain.In addition to these parameters,the internal states of the individual,such as circadian rhythm,behavior/cognition,neural oscillation,and neuroplasticity,also contribute to the variation in rTMS effects.In this review,we summarize the current literature on the interaction between rTMS and internal states.We propose two possible methods,multimodal treatment,and adaptive closed-loop treatment,to integrate patients'internal states to achieve better rTMS treatment for depression.
文摘Artificial intelligence,especially large language models(LLMs),is reshaping how we learn,communicate,and create.These systems provide students and professionals immediate access to fluent,context-aware language that can support learning,increase productivity,and spark creativity.But what happens when their use becomes excessive?This paper explores the potential long-term consequences of over-relying on LLMs-particularly memory,critical thinking,creativity,and motivation.Drawing on research in cognitive psychology,education,neuroscience,and media studies,it argues that LLMs are best understood as cognitive prostheses:incredibly valuable when used wisely,but risky when they replace rather than support human imagination.
基金supported by the National Natural Science Foundation of China(Nos.12205259 and 12147101)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)with No.G1323523064.
文摘In this study,we performed a systematic analysis of the multiplicity dependence of hadron production at mid-rapidity(|y|<0.5),ranging from the light to the charm sector in proton-proton(pp)collisions at√s=13 TeV.This study used a multi-phase transport(AMPT)model coupled with PYTHIA8 initial conditions.We investigated the baryon-to-meson and the strange-to-non-strange meson ratios varying with the charged particle density.By tuning the coalescence parameters,the AMPT model provides a reasonable description of the experimental data for the inclusive production of both light and charm hadrons,comparable to the string fragmentation model calculations with color reconnection effects.Additionally,we analyzed the relative production of hadrons by examining the self-normalized particle ratios as a function of the charged hadron density.Our findings suggest that parton evolution effects and the coalescence hadronization process in the AMPT model result in a strong flavor hierarchy in the multiplicity dependence of the baryon-to-meson ratio.Furthermore,our investigation of the p_(T) differential double ratio of the baryon-to-meson fraction between high-and low-multiplicity events revealed distinct modifications to the flavor associated baryon-to-meson ratio p_(T) shape in high-multiplicity events when comparing the coalescence hadronization model to the color reconnection model.These observations highlight the importance of understanding the hadronization process in high-energy pp collisions through comprehensive multiplicity-dependent multi-flavor analysis.
基金Anusandhan National Research Foundation(ANRF)(previously,Science and Engineering Research Board-SERB),India for the grant CRG/2022/002509.
文摘Rock slope along motorways in the Higher Himalayan terrains are prone to various types of failure.In order to effectively mitigate these failures,a thorough assessment of rock mass behavior is entailed.The present research employs and compares widely practiced geo-mechanical classification schemes viz.,RQD,RMR,SMR,Q-slope,and GSI.A 23 km road cut section,along Sangla to Chitkul route,in Higher Himalayan region(India)has been taken up for this work.Total of 18 locations were selected,and their slope and rockmass properties were examined.Afterwards,the most influencing parameters in RMR,SMR,and Q-Slope were evaluated through a machine learning algorithm,i.e.,Random Forest.For RMRbasic,about 83%of rock-slopes were designated in good condition and rest were of Fair quality.Evaluation of slope mass rating along all 18-locations highlighted eight-sites as partially unstable,six-sites as partially stable.Remaining four locations varied between,Very Bad to Bad slope-conditions,necessitating the installation of mechanical supports and redesign of slopes.For SMR classification,feature importance analysis revealed the predominance of F3 variable,RQD and intact rock strength.Q-Slope approach was incorporated to identify the most stable steepest angle of the examined locations.For Q-Slope rating,Jn and RQD were found to have the most influence in classification of the slopes.Three zones on the basis of GSI-scores have been identified in the study area,i.e.,A(6595),B(4555),and C(2535).This study highlights the application of multiple geomechanical classification schemes,demonstrating how each approach can complement the others.
基金Mental Hospital of Yunnan Province Scientific Research Fund Project(shengjingkeyan2022-11).
文摘Heroin dependence is a serious substance use disorder that not only causes great harm to physical health but also significantly affects mental health.Addicts often experience a variety of psychological problems,such as depression,anxiety,personality disorders,and cognitive impairment.In recent years the mechanisms and intervention methods related to mental health problems in heroin addicts have received widespread research attention.This article reviews the current research into mental health problems in heroin addicts in order to provide a theoretical basis for optimizing drug addiction intervention strategies.
文摘Assessing individual differences and variability in animal movement patterns is essential to improve our understanding of the evolution and ontogeny of migratory strategies.In long-distance migratory species,fledged juveniles often rely on an extremely restricted time span to learn the essential skills for survival and to prepare for migration,possibly the most risky phase of their lives.Collecting detailed information on the dynamics of the movements during the crucial pre-migratory phase is hence essential to understand the solutions developed by migratory species in different environmental contexts.Here,we used high-resolution GPS/GSM transmitters to collect information on the movement ecology of seven juvenile Montagu's Harriers(Circus pygargus)born in central Italy,investigating their early life stages,namely the post-fledging dependence period(PFDP)and the pre-migratory phase(PMP),until autumn migration.After fledging,individuals showed high variability(both in space and time)in home range size,daily distances covered(6.88±11.44 km/day),distance from the nest(1.45±2.8 km)and PFDP length(23.3±5.3 days).Residence time at the natal site significantly decreased,while time interval between revists in the natal area significantly increased,as the PFDP progressed.During the PMP,explored areas and distance from the nest(max value up to 320.8 km)varied among individuals,despite daily distances covered(27±40 km/day)and time allocation between traveling(60.7%)and foraging(39.3%)were similar across individuals.The PMP lasted 38±14 days.Land cover composition of foraging locations was mostly represented by agricultural lands(~78.2%),though habitat use differed among individuals.More than 76%of such locations were outside protected areas.This individual-based tracking study represents a novel approach that improves previous knowledge based on field studies on the early life stages of the Montagu's Harrier.High inter-individual variability in movement patterns,broad-range exploratory movements and foraging locations outside the protected area network make the application of standard conservation measures difficult,raising concerns about the long-term preservation of this vulnerable migratory species in Italy.
基金supported by the National Natural Science Foundation of China(No.21603238 to Juan Zhao,Nos.21573243 and 21327802 to Jianping Wang).
文摘Due to their high dielectric constant,low melting point,and high boiling point,nitrile-based solvents exhibit significant potential in wide-temperature-range electrolytes.In this study,a wide-temperature electrolyte system composed of lithium bis(trifluoromethanesulfonyl)imide(LiTFSI),dimethyl carbonate(DMC),and butyronitrile(BN)in a molar ratio of 1:3:9 was designed.Using variable-temperature infrared(IR)spectroscopy with carbonyl(C=O)and cyano(C≡N)groups as IR probes,combined with molecular dynamics simulations and density functional theory calculations,the temperature-dependent evolution of the Li^(+)solvation structure and molecular dynamics were systematically investigated over the range of-45℃to 45℃.The results show that the introduction of BN not only significantly enhances the low-temperature ionic conductivity and high-temperature stability of the electrolyte,but also optimizes the solvation structure and interfacial characteristics of lithium ions through strong coordination interactions.This work provides both theoretical insights and experimental support for the design of wide-temperature electrolytes.
基金supported by the National Natural Science Foundation of China(Grant Nos.92263107,U23A20570,52221001,62090035,and 52022029)the Hunan Provincial Natural Science Foundation of China(Grant No.2024RC1034)。
文摘Understanding interlayer charge transfer is crucial for elucidating interface interactions in heterostructures.As the layer number can significantly influence the interface coupling and band alignment,the charge transfer behaviors can be largely regulated.Here,we constructed two-dimensional(2D)heterostructures consisting of monolayer WS_(2)and few-layer InSe to investigate the impact of InSe thickness on exciton dynamics.We performed photoluminescence(PL)spectroscopy and lifetime measurements on pristine few-layer InSe and the heterostructures with different InSe thicknesses.For pristine InSe layers,we found a non-monotonic layer dependence on PL lifetime,which can be attributed to the interplay between the indirect-to-direct bandgap transition and surface recombination effects.For heterostructures,we demonstrated that the type I band alignment of the heterostructure facilitates electron and hole transfer from monolayer WS_(2)to InSe.As the InSe layer number increases,the reduction in conduction band minimum(CBM)enhances the driving force for charge transfer,thereby improving the transfer efficiency.Furthermore,we fabricated and characterized a WS_(2)/InSe optoelectronic device.By analyzing bias voltage dependent PL spectra,we further demonstrated that the trions in WS_(2)within the heterostructure are positively charged(X^(+)),and their emission intensity can be efficiently modulated by applying different biases.This study not only reveals the layer-dependent characteristics of band alignment and interlayer charge transfer in heterostructures but also provides valuable insights for the applications of 2D semiconductors in optoelectronic devices.
