Objectives:College students face increasing mental health challenges.Although Acceptance and CommitmentTherapy(ACT)is effective,the efficacy of Internet-based ACT(iACT)needs further exploration.Methods:This study exam...Objectives:College students face increasing mental health challenges.Although Acceptance and CommitmentTherapy(ACT)is effective,the efficacy of Internet-based ACT(iACT)needs further exploration.Methods:This study examines the efficacy of iACT on college students’mental health through a randomized controlled trial.We recruited 90 college students(19.16±1.02 years old)and randomly divided them into the iACT group,face-to-face ACT group,and control group.The effects of the interventions were evaluated using the comprehensive assessment of ACT processes(CompACT)and the Depression Anxiety Stress Scales(DASS-21).Results:Two-factor repeated measures ANOVA revealed a significant time main effect of iACT.Face-to-face ACT and iACT effectively improved college students’psychological flexibility[F(2,83)=18.78,p<0.001,η^(2)=0.18]and alleviated their negative emotions[F(2,82)=41.17,p<0.001,η^(2)=0.36].Face-to-face ACT exhibited sustained effects on improving participants’psychological flexibility and alleviating their negative emotions(p<0.001),while iACT showed no sustained effect on improving participants’psychological flexibility(p>0.05).Conclusion:While iACT and face-to-face ACT are effective shortterm interventions,face-to-face ACT demonstrates superior sustainability.Integrating guided sessions into iACT may enhance long-term outcomes.These findings advocate for blended interventions to address college students’mental health needs,particularly in resource-limited settings.展开更多
With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring ba...With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring based on SECI model and information emission model. Finally customer knowledge transferring mechanism is discussed.展开更多
Teleoperation system plays an important role in executing task under hazard environment. As the computer networks such as the Internet are being used as the communication channel of teleoperation system, varying time ...Teleoperation system plays an important role in executing task under hazard environment. As the computer networks such as the Internet are being used as the communication channel of teleoperation system, varying time delay causes the overall system unstable and reduces the performance of transparency. This paper proposed twelve operation modes with different control schemes for teleoperation on the Internet with time delay. And an optimal operation mode with control scheme was specified for teleoperation with time delay, based on the tradeoff between passivity and transparency properties. It experimentally confirmed the validity of the proposed optimal mode and control scheme by using a simple one DOF master-slave manipulator system.展开更多
Using multi-source reanalysis data,this study examines the relationship between the tropical Pacific-Atlantic SST Dipole Mode(TPA-DM)and summer precipitation in North China(NCSP)on the interannual timescale during the...Using multi-source reanalysis data,this study examines the relationship between the tropical Pacific-Atlantic SST Dipole Mode(TPA-DM)and summer precipitation in North China(NCSP)on the interannual timescale during the period of 1979-2022.The results show that the TPA-DM,the dominant pattern of interannual variability in the tropical Pacific and Atlantic regions,exhibits a significant negative correlation with NCSP.The positive phase of TPA-DM induces subsidence over the Maritime Continent through a zonal circulation pattern,which initiates a Pacific-Japan-like wave train along the East Asian coast.The circulation anomalies lead to moisture deficits and convergence subsidence over North China,leading to below-normal rainfall.Further analysis reveals that cooler SST in the Southern Tropical Atlantic facilitates the persistence of the TPA-DM by stimulating the anomalous Walker circulation associated with wind-evaporation-SST-convection feedback.展开更多
Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both g...Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations.展开更多
Background:The easy accessibility,increasing usage,and low cost of internet make it a desirable way of providing health information and delivering interventions for health consumers.Studies in other countries have ver...Background:The easy accessibility,increasing usage,and low cost of internet make it a desirable way of providing health information and delivering interventions for health consumers.Studies in other countries have verified and confirmed the effectiveness of internet-based interventions among people with mental health problems.Similar programs have yet to commence in China.Purpose:This study investigated the willingness for,and attitude toward internet-based intervention in Chinese mental health service users and explored the feasibility of such an intervention.Methods:A cross-sectional survey utilizing a self-developed questionnaire was administered to 186 mental health service users in Beijing,between April and May 2011.Results:Most participants held a positive attitude toward online information and expressed interest in getting assistance from the internet.Some advice and suggestions were provided such as more ways of getting assistance,setting up more professional websites,increasing interaction,as well as having government funding and guidance.Conclusion:Internet-based programs are feasible and applicable,and worth implementing with Chinese people with mental illness.展开更多
Manufacture is facing more furiously competition in the new century. It tends to be globalized. Rapid response and technology innovation have become the key factor to the success of manufacture enterprise. At present,...Manufacture is facing more furiously competition in the new century. It tends to be globalized. Rapid response and technology innovation have become the key factor to the success of manufacture enterprise. At present, internet-based manufacturing develops rapidly. With the development of engineering material and machining techniques, better cutting properties of metal cutting tools are required. The world is paying more attention to the study of indexable carbide inserts with three-dimensional complex grooves which can affect cutting properties directly and chip-controlling. So the variety and specification of indexable insert develop quickly and the application of insert with three-dimensional complex chip-former becomes wider and wider. Because milling is an interrupted cutting, the process of milling is complicated and the failure of the milling inserts is severe. It is important to choose suitable milling inserts groove for particular machining conditions before actual machining, it will extend tool life and raise productivity. Optimization and choice of inserts with complex groove via internet may serve for manufacture enterprises all over the world. The milling inserts with three-dimensional complex grooves are optimized and chosen via Internet in this paper. The face-milling process is studied, with the mathematics models of cutting force for different shape of cutting edges established, the cutting forces predicted and stress-fields of different insert grooves analyzed by FEM, according to the predictable results and the most suitable insert groove for particular machining conditions are optimized and chosen. The complex groove optimization and choice are based on a client/server model, with the client and server being on different machines across the internet. Communication between the client and server uses the TCP/IP. The result of optimization and choice will be sent to the users via Internet. Manufacturers all over the world can get the desired insert groove without paying for expensive experiments. Thus, the cost and lead time of products are reduced.展开更多
There is a documented and often unmet need for interventions aimed at supporting young people with attention-deficit/hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD) in their transition between adol...There is a documented and often unmet need for interventions aimed at supporting young people with attention-deficit/hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD) in their transition between adolescence and adulthood. Difficulties with social interaction, initiation difficulties, and impairments in executive function can complicate visits at a clinic, i.e. traditional treatment, for individuals with neuropsychiatric disorders (NPD). A model for internet-based support and coaching aimed at young people with ASD and/or ADHD was developed and tested at three treatment sites in western Sweden. The implementation was analyzed against an inventory according to which implementations are more likely to be successful if an intervention: 1) has advantages compared to other existing methods, 2) matches the individual and organizational values, norms and work practices of its recipients, 3) is perceived as easy to use, and 4) is adaptable to local conditions and the recipients’ needs. Data were collected through group interviews with professionals involved in the implementation of the intervention. The implementation of the intervention showed promising results on measures such as access, delivery/quality of healthcare services, and equality of distribution of healthcare services. The identified impediments to successful implementation related to a wide range of factors and levels, including the design of the intervention, technical issues, attitudes of staff, organizational culture, and organizational structure at the implementation sites in terms of patient stock, work division, and resource allocation. The results are consistent with previous studies that stress the need for multi-component implementation strategies.展开更多
Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization commun...Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization communication driven method is proposed to overcome the negative effects induced by time delay. This method is a non-time based method and it can get rid of the effects of time in the control loop of telerobotics. Stability, transparency and synchronization can be maintained in it by event-driven method. Multimodal enhanced telerobotics is put forward with its feedback including force, video, audio and temperature etc. The use of multimodal feedback improves the efficiency and safety of the whole system. Synchronization in multimodal feedback is hard to ensure and event-driven method is also good for it. Experiments on an Internet-based shaft-hole assemblage system show good results by using event synchronization communication driven method and UDP protocol.展开更多
Objectives:This study reviewed published randomized controlled trials(RCTs)and evaluated the efficacy of internet-based acceptance and commitment therapy(IACT)on adolescent mental health.Methods:Searches were conducte...Objectives:This study reviewed published randomized controlled trials(RCTs)and evaluated the efficacy of internet-based acceptance and commitment therapy(IACT)on adolescent mental health.Methods:Searches were conducted in PubMed,ProQuest,APA(PsycNET/PsycINFO),and Web of Science from inception to Jan-uary 2022 to identify RCTs evaluating the effects of IACT on adolescents.The included studies were assessed for quality and risk of bias.This study was performed using the standard mean difference and associated 95%confidence interval of effective measures.Review Manager 5.4 software was adopted to calculate the effect size.Results:Compared to adolescents in control groups,those in the IACT groups showed some improvement in the efficacy of depression symptoms(SMD=−0.24,95%CI=[−0.44,−0.05],p=0.01)and had a small but sig-nificant effect on reducing experiential avoidance(SMD=−0.24,95%CI=[−0.46,−0.01],p=0.04).However,the effect size on anxiety did not reach the threshold(SMD=−0.18,95%CI=[−0.27,−0.09],p<0.0001).In addition,there were no significant differences in stress and well-being compared to those of the control group.Compared with universal adolescents,IACT was found to have a more significant therapeutic effect on targeted adolescents.Conclusions:IACT is effective in adolescent mental health interventions,but its clinical reliability and significant efficacy are limited,and more rigorous RCTs are needed in future studies.展开更多
Two significant issues in Internet-based networked control systems ( INCSs), transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performanc...Two significant issues in Internet-based networked control systems ( INCSs), transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performance of data transmission, user datagram protocol (UDP) is adopted as the main stand for controllers and plants using INCSs. Second, a dual-channel secure transmission scheme (DCSTS)based on data transmission characteristics of INCSs is proposed, in which a raw UDP channel and a secure TCP (transmission control protocol) connection making use of SSL/TLS (secure sockets layer/transport layer security) are included. Further, a networked control protocol (NCP) at application layer for supporting DCSTS between the controllers and plants in INCSs is designed, and it also aims at providing a universal communication mechanism for interoperability of devices among the networked control laboratories in Beijing Institute of Technology of China, Central South University of China and Tokyo University of Technology of Japan. By means of a networked single-degree-of-free- dom robot arm, an INCS under the new protocol and security environment is created. Compared with systems such as IPSec or SSL/TLS, which may cause more than 91% network throughput deduction, the new DCSTS protocol may yield results ten times better, being just 5.67%.展开更多
Induction and mentoring programs aim to help new school teachers survive and thrive in their teaching profession.Among each juris-diction of Canada,there are different programs and most of them are characterized by In...Induction and mentoring programs aim to help new school teachers survive and thrive in their teaching profession.Among each juris-diction of Canada,there are different programs and most of them are characterized by Internet-based supports.On the websites of the provincial departments of education or teachers’organizations,well-designed webpages are set for induction programs,special portals are designed for new teachers,and documents relating to early career teaching are provided.Even on some local school districts’websites,induction programs and relevant documents are easily accessed.Based on the above facts,this paper also analyzes the advantages and limitations of those Internet-based approaches in Canadian teacher in-duction activities.展开更多
Spoken language is such an important part in learning English that College English Curriculum Requirement considers promoting the students' spoken language as one of the most important goals in teaching English.Ho...Spoken language is such an important part in learning English that College English Curriculum Requirement considers promoting the students' spoken language as one of the most important goals in teaching English.However,at present,the students' oral expression competence is not so good in colleges.It is urgent to improve the quality of oral English classes and solve mute English of the students in colleges.Internet-based teaching is the new teaching mode adapting to the trend of the times.Internet provides excellent interactive methods for inquiry learning mode and provides the possibility for constructing an open learning environment.展开更多
The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconci...The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconcile this contradiction,two Mg-0.1Sc-0.1Y-0.1Ag anodes with different residual strain distribution through extrusion with/without annealing are fabricated.The results indicate that annealing can significantly lessen the“pseudo-anode”regions,thereby changing the dissolution mode of the matrix and achieving an effective dissolution during discharge.Additionally,p-type semiconductor characteristic of discharge productfilm could suppress the self-corrosion reaction without reducing the polarization of anode.The magnesium-air battery utilizing annealed Mg-0.1Sc-0.1Y-0.1Ag as anode achieves a synergistic improvement in specific capacity(1388.89 mA h g^(-1))and energy density(1960.42 mW h g^(-1)).This anode modification method accelerates the advancement of high efficiency and long lifespan magnesium-air batteries,offering renewable and cost-effective energy solutions for electronics and emergency equipment.展开更多
A custom micro-arc oxidation(MAO)apparatus is employed to produce coatings under optimized constant voltage–current two-step power supply mode.Various analytical techniques,including scanning electron microscopy,conf...A custom micro-arc oxidation(MAO)apparatus is employed to produce coatings under optimized constant voltage–current two-step power supply mode.Various analytical techniques,including scanning electron microscopy,confocal laser microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,and electrochemical analysis,are employed to characterize MAO coatings at different stages of preparation.MAO has MgO,hydroxyapatite,Ca_(3)(PO_(4))_(2),and Mg2SiO4 phases.Its microstructure of the coating is characterized by"multiple breakdowns,pores within pores",and"repaired blind pores".The porosity and the uniformity of MAO coating first declines in the constant voltage mode,then augments while the discharge phenomenon takes place,and finally decreases in the repair stage.These analyses reveal a four-stage growth pattern for MAO coatings:anodic oxidation stage,micro-arc oxidation stage,breakdown stage,and repairing stage.During anodic oxidation and MAO stages,inward growth prevails,while the breakdown stage sees outward and accelerated growth.Simultaneous inward and outward growth in the repair stage results in a denser,more uniform coating with increased thickness and improved corrosion resistance.展开更多
In 316L austenitic stainless steel,the presence of ferrite phase severely affects the non-magnetic properties.316L austenitic stainless steel with low-alloy type(L-316L)and high-alloy type(H-316L)has been studied.The ...In 316L austenitic stainless steel,the presence of ferrite phase severely affects the non-magnetic properties.316L austenitic stainless steel with low-alloy type(L-316L)and high-alloy type(H-316L)has been studied.The microstructure and solidification kinetics of the two as-cast grades were in situ observed by high temperature confocal laser scanning microscopy(HT-CLSM).There are significant differences in the as-cast microstructures of the two 316L stainless steel compositions.In L-316L steel,ferrite morphology appears as the short rods with a ferrite content of 6.98%,forming a dual-phase microstructure consisting of austenite and ferrite.Conversely,in H-316L steel,the ferrite appears as discontinuous network structures with a content of 4.41%,forming a microstructure composed of austenite and sigma(σ)phase.The alloying elements in H-316L steel exhibit a complex distribution,with Ni and Mo enriching at the austenite grain boundaries.HT-CLSM experiments provide the real-time observation of the solidification processes of both 316L specimens and reveal distinct solidification modes:L-316L steel solidifies in an FA mode,whereas H-316L steel solidifies in an AF mode.These differences result in ferrite and austenite predominantly serving as the nucleation and growth phases,respectively.The solidification mode observed by experiments is similar to the thermodynamic calculation results.The L-316L steel solidified in the FA mode and showed minimal element segregation,which lead to a direct transformation of ferrite to austenite phase(δ→γ)during phase transformation after solidification.Besides,the H-316L steel solidified in the AF mode and showed severe element segregation,which lead to Mo enrichment at grain boundaries and transformation of ferrite into sigma and austenite phases through the eutectoid reaction(δ→σ+γ).展开更多
Due to scale effects,micromechanical resonators offer an excellent platform for investigating the intrinsic mechanisms of nonlinear dynamical phenomena and their potential applications.This review focuses on mode-coup...Due to scale effects,micromechanical resonators offer an excellent platform for investigating the intrinsic mechanisms of nonlinear dynamical phenomena and their potential applications.This review focuses on mode-coupled micromechanical resonators,highlighting the latest advancements in four key areas:internal resonance,synchronization,frequency combs,and mode localization.The origin,development,and potential applications of each of these dynamic phenomena within mode-coupled micromechanical systems are investigated,with the goal of inspiring new ideas and directions for researchers in this field.展开更多
This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic mo...This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual inputs.Secondly,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown disturbances.The whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function method.Furthermore,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and rudder.Actuator dynamic models are incorporated to ensure physical realizability of designed allocation law.Finally,comparative experimental results validate the effectiveness of the designed control system and control allocation law.The NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),respectively.The design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering.展开更多
With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure m...With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure modes are transformed.In order to reveal the failure mode and transformation rule of reinforced concrete slabs under impact loads,a dynamic impact response test was carried out using a drop hammer test device.The dynamic data pertaining to the impact force,support reaction force,structural displacement,and reinforcement strain were obtained through the use of digital image correlation technology(DIC),impact force measurement,and strain measurement.The analysis of the ultimate damage state of the reinforced concrete slab identified four distinct types of impact failure modes:local failure by stamping,overall failure by stamping,local-overall coupling failure,and local failure by punching.Additionally,the influence laws of hammerhead shape,hammer height,and reinforcement ratio on the dynamic response and failure mode transformation of the slab were revealed.The results indicate that:(1)The local damage to the slab by the plane hammer is readily apparent,while the overall damage by the spherical hammer is more pronounced.(2)In comparison to the high reinforcement ratio slabs,the overall bending resistance of the low reinforcement ratio slabs is significantly inferior,and the slab back exhibits further cracks.(3)As the hammer height increases,the slab failure mode undergoes a transformation,shifting from local failure by stamping and overall failure by stamping to local-overall coupling failure and local failure by punching.(4)Three failure mode thresholds have been established,and by comparing the peak impact force with the failure thresholds,the failure mode of the slab can be effectively determined.展开更多
基金funded by the Education and Teaching Reform Research Major Project of Anhui Province(2022xqhz023)(2023sx170).
文摘Objectives:College students face increasing mental health challenges.Although Acceptance and CommitmentTherapy(ACT)is effective,the efficacy of Internet-based ACT(iACT)needs further exploration.Methods:This study examines the efficacy of iACT on college students’mental health through a randomized controlled trial.We recruited 90 college students(19.16±1.02 years old)and randomly divided them into the iACT group,face-to-face ACT group,and control group.The effects of the interventions were evaluated using the comprehensive assessment of ACT processes(CompACT)and the Depression Anxiety Stress Scales(DASS-21).Results:Two-factor repeated measures ANOVA revealed a significant time main effect of iACT.Face-to-face ACT and iACT effectively improved college students’psychological flexibility[F(2,83)=18.78,p<0.001,η^(2)=0.18]and alleviated their negative emotions[F(2,82)=41.17,p<0.001,η^(2)=0.36].Face-to-face ACT exhibited sustained effects on improving participants’psychological flexibility and alleviating their negative emotions(p<0.001),while iACT showed no sustained effect on improving participants’psychological flexibility(p>0.05).Conclusion:While iACT and face-to-face ACT are effective shortterm interventions,face-to-face ACT demonstrates superior sustainability.Integrating guided sessions into iACT may enhance long-term outcomes.These findings advocate for blended interventions to address college students’mental health needs,particularly in resource-limited settings.
文摘With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring based on SECI model and information emission model. Finally customer knowledge transferring mechanism is discussed.
基金Foundation for U niversity Key Teacher bythe Ministry of Education and National Natural Science Founda-tion of China ( No.69875 0 0 4) and 863 High-Tech Plan ( No.2 0 0 1AA42 3 2 40 )
文摘Teleoperation system plays an important role in executing task under hazard environment. As the computer networks such as the Internet are being used as the communication channel of teleoperation system, varying time delay causes the overall system unstable and reduces the performance of transparency. This paper proposed twelve operation modes with different control schemes for teleoperation on the Internet with time delay. And an optimal operation mode with control scheme was specified for teleoperation with time delay, based on the tradeoff between passivity and transparency properties. It experimentally confirmed the validity of the proposed optimal mode and control scheme by using a simple one DOF master-slave manipulator system.
基金jointly supported by the Second Tibetan Plateau Scientific Expedition and Research Program[grant number-ber 2019QZKK0103]the National Natural Science Foundation of China[grant number 42293294]the China Meteorological Admin-istration Climate Change Special Program[grant number QBZ202303]。
文摘Using multi-source reanalysis data,this study examines the relationship between the tropical Pacific-Atlantic SST Dipole Mode(TPA-DM)and summer precipitation in North China(NCSP)on the interannual timescale during the period of 1979-2022.The results show that the TPA-DM,the dominant pattern of interannual variability in the tropical Pacific and Atlantic regions,exhibits a significant negative correlation with NCSP.The positive phase of TPA-DM induces subsidence over the Maritime Continent through a zonal circulation pattern,which initiates a Pacific-Japan-like wave train along the East Asian coast.The circulation anomalies lead to moisture deficits and convergence subsidence over North China,leading to below-normal rainfall.Further analysis reveals that cooler SST in the Southern Tropical Atlantic facilitates the persistence of the TPA-DM by stimulating the anomalous Walker circulation associated with wind-evaporation-SST-convection feedback.
基金supported by the National Natural Science Foundation of China(Grant Nos.U2342210 and 42275043)the National Institute of Natural Hazards,Ministry of Emergency Management of China(Grant Nos.J2223806,ZDJ2024-25 and ZDJ2025-34)。
文摘Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations.
文摘Background:The easy accessibility,increasing usage,and low cost of internet make it a desirable way of providing health information and delivering interventions for health consumers.Studies in other countries have verified and confirmed the effectiveness of internet-based interventions among people with mental health problems.Similar programs have yet to commence in China.Purpose:This study investigated the willingness for,and attitude toward internet-based intervention in Chinese mental health service users and explored the feasibility of such an intervention.Methods:A cross-sectional survey utilizing a self-developed questionnaire was administered to 186 mental health service users in Beijing,between April and May 2011.Results:Most participants held a positive attitude toward online information and expressed interest in getting assistance from the internet.Some advice and suggestions were provided such as more ways of getting assistance,setting up more professional websites,increasing interaction,as well as having government funding and guidance.Conclusion:Internet-based programs are feasible and applicable,and worth implementing with Chinese people with mental illness.
文摘Manufacture is facing more furiously competition in the new century. It tends to be globalized. Rapid response and technology innovation have become the key factor to the success of manufacture enterprise. At present, internet-based manufacturing develops rapidly. With the development of engineering material and machining techniques, better cutting properties of metal cutting tools are required. The world is paying more attention to the study of indexable carbide inserts with three-dimensional complex grooves which can affect cutting properties directly and chip-controlling. So the variety and specification of indexable insert develop quickly and the application of insert with three-dimensional complex chip-former becomes wider and wider. Because milling is an interrupted cutting, the process of milling is complicated and the failure of the milling inserts is severe. It is important to choose suitable milling inserts groove for particular machining conditions before actual machining, it will extend tool life and raise productivity. Optimization and choice of inserts with complex groove via internet may serve for manufacture enterprises all over the world. The milling inserts with three-dimensional complex grooves are optimized and chosen via Internet in this paper. The face-milling process is studied, with the mathematics models of cutting force for different shape of cutting edges established, the cutting forces predicted and stress-fields of different insert grooves analyzed by FEM, according to the predictable results and the most suitable insert groove for particular machining conditions are optimized and chosen. The complex groove optimization and choice are based on a client/server model, with the client and server being on different machines across the internet. Communication between the client and server uses the TCP/IP. The result of optimization and choice will be sent to the users via Internet. Manufacturers all over the world can get the desired insert groove without paying for expensive experiments. Thus, the cost and lead time of products are reduced.
文摘There is a documented and often unmet need for interventions aimed at supporting young people with attention-deficit/hyperactivity disorder (ADHD) and/or autism spectrum disorder (ASD) in their transition between adolescence and adulthood. Difficulties with social interaction, initiation difficulties, and impairments in executive function can complicate visits at a clinic, i.e. traditional treatment, for individuals with neuropsychiatric disorders (NPD). A model for internet-based support and coaching aimed at young people with ASD and/or ADHD was developed and tested at three treatment sites in western Sweden. The implementation was analyzed against an inventory according to which implementations are more likely to be successful if an intervention: 1) has advantages compared to other existing methods, 2) matches the individual and organizational values, norms and work practices of its recipients, 3) is perceived as easy to use, and 4) is adaptable to local conditions and the recipients’ needs. Data were collected through group interviews with professionals involved in the implementation of the intervention. The implementation of the intervention showed promising results on measures such as access, delivery/quality of healthcare services, and equality of distribution of healthcare services. The identified impediments to successful implementation related to a wide range of factors and levels, including the design of the intervention, technical issues, attitudes of staff, organizational culture, and organizational structure at the implementation sites in terms of patient stock, work division, and resource allocation. The results are consistent with previous studies that stress the need for multi-component implementation strategies.
文摘Based on QoS (quality of service) parameters: time delay, jitter, bandwidth and package loss. As time delay in the Internet is variable, it is hard to compensate it by traditional methods. Event synchronization communication driven method is proposed to overcome the negative effects induced by time delay. This method is a non-time based method and it can get rid of the effects of time in the control loop of telerobotics. Stability, transparency and synchronization can be maintained in it by event-driven method. Multimodal enhanced telerobotics is put forward with its feedback including force, video, audio and temperature etc. The use of multimodal feedback improves the efficiency and safety of the whole system. Synchronization in multimodal feedback is hard to ensure and event-driven method is also good for it. Experiments on an Internet-based shaft-hole assemblage system show good results by using event synchronization communication driven method and UDP protocol.
基金the Humanities and Social Sciences Key Research Base Project of Anhui Province(SK2017A0278).
文摘Objectives:This study reviewed published randomized controlled trials(RCTs)and evaluated the efficacy of internet-based acceptance and commitment therapy(IACT)on adolescent mental health.Methods:Searches were conducted in PubMed,ProQuest,APA(PsycNET/PsycINFO),and Web of Science from inception to Jan-uary 2022 to identify RCTs evaluating the effects of IACT on adolescents.The included studies were assessed for quality and risk of bias.This study was performed using the standard mean difference and associated 95%confidence interval of effective measures.Review Manager 5.4 software was adopted to calculate the effect size.Results:Compared to adolescents in control groups,those in the IACT groups showed some improvement in the efficacy of depression symptoms(SMD=−0.24,95%CI=[−0.44,−0.05],p=0.01)and had a small but sig-nificant effect on reducing experiential avoidance(SMD=−0.24,95%CI=[−0.46,−0.01],p=0.04).However,the effect size on anxiety did not reach the threshold(SMD=−0.18,95%CI=[−0.27,−0.09],p<0.0001).In addition,there were no significant differences in stress and well-being compared to those of the control group.Compared with universal adolescents,IACT was found to have a more significant therapeutic effect on targeted adolescents.Conclusions:IACT is effective in adolescent mental health interventions,but its clinical reliability and significant efficacy are limited,and more rigorous RCTs are needed in future studies.
文摘Two significant issues in Internet-based networked control systems ( INCSs), transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performance of data transmission, user datagram protocol (UDP) is adopted as the main stand for controllers and plants using INCSs. Second, a dual-channel secure transmission scheme (DCSTS)based on data transmission characteristics of INCSs is proposed, in which a raw UDP channel and a secure TCP (transmission control protocol) connection making use of SSL/TLS (secure sockets layer/transport layer security) are included. Further, a networked control protocol (NCP) at application layer for supporting DCSTS between the controllers and plants in INCSs is designed, and it also aims at providing a universal communication mechanism for interoperability of devices among the networked control laboratories in Beijing Institute of Technology of China, Central South University of China and Tokyo University of Technology of Japan. By means of a networked single-degree-of-free- dom robot arm, an INCS under the new protocol and security environment is created. Compared with systems such as IPSec or SSL/TLS, which may cause more than 91% network throughput deduction, the new DCSTS protocol may yield results ten times better, being just 5.67%.
基金supported by Humanities and Social Sciences Planning Fund Project,Ministry of Education of the PRC(under Grant No.18YJA880102).
文摘Induction and mentoring programs aim to help new school teachers survive and thrive in their teaching profession.Among each juris-diction of Canada,there are different programs and most of them are characterized by Internet-based supports.On the websites of the provincial departments of education or teachers’organizations,well-designed webpages are set for induction programs,special portals are designed for new teachers,and documents relating to early career teaching are provided.Even on some local school districts’websites,induction programs and relevant documents are easily accessed.Based on the above facts,this paper also analyzes the advantages and limitations of those Internet-based approaches in Canadian teacher in-duction activities.
文摘Spoken language is such an important part in learning English that College English Curriculum Requirement considers promoting the students' spoken language as one of the most important goals in teaching English.However,at present,the students' oral expression competence is not so good in colleges.It is urgent to improve the quality of oral English classes and solve mute English of the students in colleges.Internet-based teaching is the new teaching mode adapting to the trend of the times.Internet provides excellent interactive methods for inquiry learning mode and provides the possibility for constructing an open learning environment.
基金the National Natural Science:Foundation of China(52375370)the Open Project of Salt Lake Chemical Engineering Research Complex,Qinghai University(2023-DXSSKF-Z02)+2 种基金the Nat-ural Science Foundation of Shanxi(202103021224049)GDAS Projects of International cooperation platform of Sci-ence and Technology(2022GDASZH-2022010203-003)Guangdong province Science and Technology Plan Projects(2023B1212060045).
文摘The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconcile this contradiction,two Mg-0.1Sc-0.1Y-0.1Ag anodes with different residual strain distribution through extrusion with/without annealing are fabricated.The results indicate that annealing can significantly lessen the“pseudo-anode”regions,thereby changing the dissolution mode of the matrix and achieving an effective dissolution during discharge.Additionally,p-type semiconductor characteristic of discharge productfilm could suppress the self-corrosion reaction without reducing the polarization of anode.The magnesium-air battery utilizing annealed Mg-0.1Sc-0.1Y-0.1Ag as anode achieves a synergistic improvement in specific capacity(1388.89 mA h g^(-1))and energy density(1960.42 mW h g^(-1)).This anode modification method accelerates the advancement of high efficiency and long lifespan magnesium-air batteries,offering renewable and cost-effective energy solutions for electronics and emergency equipment.
文摘A custom micro-arc oxidation(MAO)apparatus is employed to produce coatings under optimized constant voltage–current two-step power supply mode.Various analytical techniques,including scanning electron microscopy,confocal laser microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,and electrochemical analysis,are employed to characterize MAO coatings at different stages of preparation.MAO has MgO,hydroxyapatite,Ca_(3)(PO_(4))_(2),and Mg2SiO4 phases.Its microstructure of the coating is characterized by"multiple breakdowns,pores within pores",and"repaired blind pores".The porosity and the uniformity of MAO coating first declines in the constant voltage mode,then augments while the discharge phenomenon takes place,and finally decreases in the repair stage.These analyses reveal a four-stage growth pattern for MAO coatings:anodic oxidation stage,micro-arc oxidation stage,breakdown stage,and repairing stage.During anodic oxidation and MAO stages,inward growth prevails,while the breakdown stage sees outward and accelerated growth.Simultaneous inward and outward growth in the repair stage results in a denser,more uniform coating with increased thickness and improved corrosion resistance.
基金support of the Research Project Supported by Shanxi Scholarship Council of China(2022-040)"Chunhui Plan"Collaborative Research Project by the Ministry of Education of China(HZKY20220507)+2 种基金National Natural Science Foundation of China(52104338)Applied Fundamental Research Programs of Shanxi Province(202303021221036)Shandong Postdoctoral Science Foundation(SDCX-ZG-202303027,SDBX2023054).
文摘In 316L austenitic stainless steel,the presence of ferrite phase severely affects the non-magnetic properties.316L austenitic stainless steel with low-alloy type(L-316L)and high-alloy type(H-316L)has been studied.The microstructure and solidification kinetics of the two as-cast grades were in situ observed by high temperature confocal laser scanning microscopy(HT-CLSM).There are significant differences in the as-cast microstructures of the two 316L stainless steel compositions.In L-316L steel,ferrite morphology appears as the short rods with a ferrite content of 6.98%,forming a dual-phase microstructure consisting of austenite and ferrite.Conversely,in H-316L steel,the ferrite appears as discontinuous network structures with a content of 4.41%,forming a microstructure composed of austenite and sigma(σ)phase.The alloying elements in H-316L steel exhibit a complex distribution,with Ni and Mo enriching at the austenite grain boundaries.HT-CLSM experiments provide the real-time observation of the solidification processes of both 316L specimens and reveal distinct solidification modes:L-316L steel solidifies in an FA mode,whereas H-316L steel solidifies in an AF mode.These differences result in ferrite and austenite predominantly serving as the nucleation and growth phases,respectively.The solidification mode observed by experiments is similar to the thermodynamic calculation results.The L-316L steel solidified in the FA mode and showed minimal element segregation,which lead to a direct transformation of ferrite to austenite phase(δ→γ)during phase transformation after solidification.Besides,the H-316L steel solidified in the AF mode and showed severe element segregation,which lead to Mo enrichment at grain boundaries and transformation of ferrite into sigma and austenite phases through the eutectoid reaction(δ→σ+γ).
基金supported by the National Key Research and Development Program of China(No.2022YFB3203600)the National Natural Science Foundation of China(Nos.12202355,12132013,and 12172323)the Zhejiang Provincial Natural Science Foundation of China(No.LZ22A020003)。
文摘Due to scale effects,micromechanical resonators offer an excellent platform for investigating the intrinsic mechanisms of nonlinear dynamical phenomena and their potential applications.This review focuses on mode-coupled micromechanical resonators,highlighting the latest advancements in four key areas:internal resonance,synchronization,frequency combs,and mode localization.The origin,development,and potential applications of each of these dynamic phenomena within mode-coupled micromechanical systems are investigated,with the goal of inspiring new ideas and directions for researchers in this field.
基金supported by the National Natural Science Foundation of China(Nos.62103052 and No.52175214)。
文摘This paper presents the design of an asymmetrically variable wingtip anhedral angles morphing aircraft,inspired by biomimetic mechanisms,to enhance lateral maneuver capability.Firstly,we establish a lateral dynamic model considering additional forces and moments resulting during the morphing process,and convert it into a Multiple Input Multiple Output(MIMO)virtual control system by importing virtual inputs.Secondly,a classical dynamics inversion controller is designed for the outer-loop system.A new Global Fast Terminal Incremental Sliding Mode Controller(NDO-GFTISMC)is proposed for the inner-loop system,in which an adaptive law is implemented to weaken control surface chattering,and a Nonlinear Disturbance Observer(NDO)is integrated to compensate for unknown disturbances.The whole control system is proven semiglobally uniformly ultimately bounded based on the multi-Lyapunov function method.Furthermore,we consider tracking errors and self-characteristics of actuators,a quadratic programmingbased dynamic control allocation law is designed,which allocates virtual control inputs to the asymmetrically deformed wingtip and rudder.Actuator dynamic models are incorporated to ensure physical realizability of designed allocation law.Finally,comparative experimental results validate the effectiveness of the designed control system and control allocation law.The NDO-GFTISMC features faster convergence,stronger robustness,and 81.25%and 75.0%reduction in maximum state tracking error under uncertainty compared to the Incremental Nonlinear Dynamic Inversion Controller based on NDO(NDO-INDI)and Incremental Sliding Mode Controller based on NDO(NDO-ISMC),respectively.The design of the morphing aircraft significantly enhances lateral maneuver capability,maintaining a substantial control margin during lateral maneuvering,reducing the burden of the rudder surface,and effectively solving the actuator saturation problem of traditional aircraft during lateral maneuvering.
基金Supported by the National Natural Science Foundation of China(Grant No.52078283)Shandong Provincial Natural Science Foundation(Project No.ZR2024MA094)。
文摘With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure modes are transformed.In order to reveal the failure mode and transformation rule of reinforced concrete slabs under impact loads,a dynamic impact response test was carried out using a drop hammer test device.The dynamic data pertaining to the impact force,support reaction force,structural displacement,and reinforcement strain were obtained through the use of digital image correlation technology(DIC),impact force measurement,and strain measurement.The analysis of the ultimate damage state of the reinforced concrete slab identified four distinct types of impact failure modes:local failure by stamping,overall failure by stamping,local-overall coupling failure,and local failure by punching.Additionally,the influence laws of hammerhead shape,hammer height,and reinforcement ratio on the dynamic response and failure mode transformation of the slab were revealed.The results indicate that:(1)The local damage to the slab by the plane hammer is readily apparent,while the overall damage by the spherical hammer is more pronounced.(2)In comparison to the high reinforcement ratio slabs,the overall bending resistance of the low reinforcement ratio slabs is significantly inferior,and the slab back exhibits further cracks.(3)As the hammer height increases,the slab failure mode undergoes a transformation,shifting from local failure by stamping and overall failure by stamping to local-overall coupling failure and local failure by punching.(4)Three failure mode thresholds have been established,and by comparing the peak impact force with the failure thresholds,the failure mode of the slab can be effectively determined.