The Kulpawn River Basin(KRB)plays a critical role in supporting rural livelihoods through agriculture,water supply,and biodiversity conservation.However,between 1995 and 2023,significant land use and land cover(LULC)c...The Kulpawn River Basin(KRB)plays a critical role in supporting rural livelihoods through agriculture,water supply,and biodiversity conservation.However,between 1995 and 2023,significant land use and land cover(LULC)changes have been observed,affecting ecosystem services(ESs).This study evaluated the ecosystem service values(ESVs)associated with LULC changes.The random forest algorithm was applied to extract LULC information from Landsat images for 1995,2005,2015,and 2023.The benefit transfer method was employed to estimate the ESVs over the study period.Questionnaires were also used to assess the views of respondents on the drivers of the ES changes in the basin.The results showed that agricultural lands expanded by 14.14%,built-up areas by 15.17%,and light savannah forest by 8.73%,while dense savannah forest and water bodies declined by 25.71%and 20.00%,respectively.The total estimated ESV was 410.09×10^(8),362.92×10^(8),335.30×10^(8),and 319.28×10^(8) USD/(hm^(2)·a)in 1995,2005,2015,and 2023,respectively,indicating that the total ESV declined from 410.09×10^(8) USD/(hm^(2)·a)in 1995 to 319.28×10^(8) USD/(hm^(2)·a)in 2023.The study concludes that the reduction in ESVs is due to the LULC changes resulting from agricultural activities,expansion of built-up areas,population sprawl,and artisanal mining activities.Hence,there is an urgent need to develop programs and strategies to mitigate and curtail the degradation of LULC and ESVs in the basin.These findings reveal a growing ecological vulnerability,threatening water security and rural livelihoods.The study offers valuable insights to guide sustainable land use planning and ecosystem conservation strategies.展开更多
As Internet ofThings(IoT)technologies continue to evolve at an unprecedented pace,intelligent big data control and information systems have become critical enablers for organizational digital transformation,facilitati...As Internet ofThings(IoT)technologies continue to evolve at an unprecedented pace,intelligent big data control and information systems have become critical enablers for organizational digital transformation,facilitating data-driven decision making,fostering innovation ecosystems,and maintaining operational stability.In this study,we propose an advanced deployment algorithm for Service Function Chaining(SFC)that leverages an enhanced Practical Byzantine Fault Tolerance(PBFT)mechanism.The main goal is to tackle the issues of security and resource efficiency in SFC implementation across diverse network settings.By integrating blockchain technology and Deep Reinforcement Learning(DRL),our algorithm not only optimizes resource utilization and quality of service but also ensures robust security during SFC deployment.Specifically,the enhanced PBFT consensus mechanism(VRPBFT)significantly reduces consensus latency and improves Byzantine node detection through the introduction of a Verifiable Random Function(VRF)and a node reputation grading model.Experimental results demonstrate that compared to traditional PBFT,the proposed VRPBFT algorithm reduces consensus latency by approximately 30%and decreases the proportion of Byzantine nodes by 40%after 100 rounds of consensus.Furthermore,the DRL-based SFC deployment algorithm(SDRL)exhibits rapid convergence during training,with improvements in long-term average revenue,request acceptance rate,and revenue/cost ratio of 17%,14.49%,and 20.35%,respectively,over existing algorithms.Additionally,the CPU resource utilization of the SDRL algorithmreaches up to 42%,which is 27.96%higher than other algorithms.These findings indicate that the proposed algorithm substantially enhances resource utilization efficiency,service quality,and security in SFC deployment.展开更多
Mobile service robots(MSRs)in hospital environments require precise and robust trajectory tracking to ensure reliable operation under dynamic conditions,including model uncertainties and external disturbances.This stu...Mobile service robots(MSRs)in hospital environments require precise and robust trajectory tracking to ensure reliable operation under dynamic conditions,including model uncertainties and external disturbances.This study presents a cognitive control strategy that integrates a Numerical Feedforward Inverse Dynamic Controller(NFIDC)with a Feedback Radial Basis Function Neural Network(FRBFNN).The robot’s mechanical structure was designed in SolidWorks 2022 SP2.0 and validated under operational loads using finite element analysis in ANSYS 2022 R1.The NFIDC-FRBFNN framework merges proactive inverse dynamic compensation with adaptive neural learning to achieve smooth torque responses and accurate motion control.A two-stage simulation evaluation was conducted.In the first stage,the controller was tested in a simulated hospital environment under both ideal and non-ideal conditions.In the second,it was benchmarked against four established controllers-Neural Network Model Reference Adaptive(NNMRA),Z-number Fuzzy Logic(Z-FL),Adaptive Dynamic Controller(ADC),and Fuzzy Logic-PID(FL-PID)—using circular and lemniscate trajectories.Across ten runs,the proposed controller achieved the lowest tracking errors under all conditions.Under ideal conditions,it achieved average improvements of 55.24%,75.75%,and 55.20%in integral absolute error(IAE),integral squared error(ISE),and mean absolute error(MAE),respectively,with coefficient of variation(CV)reductions above 55%.Under non-ideal conditions,average improvements exceeded 64%in IAE,77%in ISE,and 66%in MAE,while maintaining CV reductions above 57%.These results confirm that the NFIDC-FRBFNN controller offers superior accuracy,robustness,and consistency for real-time path tracking in healthcare robotics.展开更多
In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenan...In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenance of biodiversity in Meizhou by the methods of market price,shadow prices approach and opportunity cost,and the problems of the value assessment at home and abroad in urban forest ecosystem services function were simply discussed.展开更多
Cryosphere science research and development(R&D) has been strongly committed to public service, integrating natural sciences with socioeconomic impacts. Owing to the current shift from purely natural cryosphere sc...Cryosphere science research and development(R&D) has been strongly committed to public service, integrating natural sciences with socioeconomic impacts. Owing to the current shift from purely natural cryosphere scientific research to linking cryosphere science with socioeconomic and cultural science, cross-disciplinary research in this field is emerging, which advocates future cryosphere science research in this field. Utilizing the cryosphere service function(CSF), this study establishes CSF and its value evaluation system. Cryosphere service valuation can benefit the decisionmakers' and public's awareness of environmental protection. Implementing sustainable CSF utilization strategies and macroeconomic policymaking for global environmental protection will have profound and practical significance as well as avoid environmental degradation while pursuing short-term economic profits and achieving rapid economic development.展开更多
Service function chains(SFC)mapping takes the responsibility for managing virtual network functions(VNFs).In SFC mapping,existing solutions duplicate VNFs with redundant instances to provide high availability in respo...Service function chains(SFC)mapping takes the responsibility for managing virtual network functions(VNFs).In SFC mapping,existing solutions duplicate VNFs with redundant instances to provide high availability in response to failures.However,as a compromise,these solutions result in high resource consumption due to device maintenance.In this paper,we propose a novel method named dynamic backup sharing(DBS)that allows SFCs to dynamically share backups to reduce resource consumption.DBS formulates the problem of sharing backups among different VNFs as an integer linear programming(ILP).Thereafter,we design a novel online algorithm based on dynamic programming to solve the problem.The experimental results indicate that DBS outperforms state-ofthe-art works by reducing resource consumption and improving the number of accepted requests.展开更多
Software Defined Satellite Networks(SDSN) are proposed to solve the problems in traditional satellite networks, such as time-consuming configuration and inflexible traffic scheduling. The emerging application of small...Software Defined Satellite Networks(SDSN) are proposed to solve the problems in traditional satellite networks, such as time-consuming configuration and inflexible traffic scheduling. The emerging application of small satellite and research of SDSN make it possible for satellite networks to provide flexible network services. Service Function Chain(SFC) can satisfy this need. In this paper, we are motivated to investigate applying SFC in the small satellite-based SDSN for service delivery. We introduce the structure of the multi-layer constellation-based SDSN. Then, we describe two deployment patterns of SFC in SDSN, the Multi-Domain(MD) pattern and the Satellite Formation(SF) pattern. We propose two algorithms, SFP-MD, and SFP-SF, to calculate the Service Function Path(SFP). We implement the algorithms and conduct contrast experiments in our prototype. Finally, we summarize the applicable conditions of two deployment patterns according to the experimental results in terms of hops, delay, and packet loss rate.展开更多
With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)sat...With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)satellite networks.While due to the scarcity of bandwidth resources and dynamic topology of LEO satellites,the static SFC placement schemes may cause performance degradation,resource waste and even service failure.In this paper,we consider migration and establish an online migration model,especially considering the dynamic topology.Given the scarcity of bandwidth resources,the model aims to maximize the total number of accepted SFCs while incurring as little bandwidth cost of SFC transmission and migration as possible.Due to its NP-hardness,we propose a heuristic minimized dynamic SFC migration(MDSM)algorithm that only triggers the migration procedure when new SFCs are rejected.Simulation results demonstrate that MDSM achieves a performance close to the upper bound with lower complexity.展开更多
Animal husbandry is the pillar industry in some ethnic areas of China.However,the communication/networking infrastructure in these areas is often underdeveloped,thus the difficulty in centralized management,and challe...Animal husbandry is the pillar industry in some ethnic areas of China.However,the communication/networking infrastructure in these areas is often underdeveloped,thus the difficulty in centralized management,and challenges for the effective monitoring.Considering the dynamics of the field monitoring environment,as well as the diversity and mobility of monitoring targets,traditional WSN(Wireless Sensor Networks)or IoT(Internet of Things)is difficult to meet the surveillance needs.Mobile surveillance that features the collaboration of various functions(camera,sensing,image recognition,etc.)deployed on mobile devices is desirable in a volatile wireless environment.This paper proposes the service function chaining for mobile surveillance of animal husbandry,which orchestrates multi-path multifunction(MPMF)chains to help mobile devices to collaborate in complex surveillance tasks,provide backup chains in case the primary service function chain fails due to mobility,signal strength,obstacle,etc.,and make up for the defects of difficult deployment of monitoring facilities in ethnic areas.MPMF algorithmmodels both mobile devices and various functions deployed on them as abstract graph nodes,so that chains that are required to traverse various functions and hosting mobile devices can be orchestrated in a single graphbased query through modified and adapted Dijkstra-like algorithms,with their cost ordered automatically.Experiment results show that the proposed MPMF algorithm finds multiple least-costly chains that traverse demanded functions in a timely fashion on Raspberry Pi-equipped mobile devices.展开更多
Based on the measurement parameters and index in the Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008),the value of ecological service functions of ecological public welfare forest in...Based on the measurement parameters and index in the Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008),the value of ecological service functions of ecological public welfare forest in Wenchang City was evaluated and analyzed.The results show that the total value of ecosystem service function of ecological public welfare forests in Wenchang City is about 4.020 billion yuan,of which storage capacity,water purification,soil fixation,fertilizer(N,P and K fertilizer) conservation,carbon sequestration,oxygen release,forest nutrient accumulation,providing anion,absorbing SO_2,absorbing fluoride,absorbing NxO,absorbing soil heavy metals,dust retention,noise reduction,sterilization,forest protection,forest biodiversity protection,and forest recreation(ecological tourism) are about 1.510 billion,582.256 million,3.769 million,268.220 million,116.360 million,2.747 million,22.682 million,42.817 million,1.722 million,74,600,131,900,187.918 million,77.409 million,28.721 million,43.090 million,180.696 million,571.036 million,and 108.677 million yuan展开更多
Network function virtualization is a new network concept that moves network functions from dedicated hardware to software-defined applications running on standard high volume severs. In order to accomplish network ser...Network function virtualization is a new network concept that moves network functions from dedicated hardware to software-defined applications running on standard high volume severs. In order to accomplish network services, traffic flows are usually processed by a list of network functions in sequence which is defined by service function chain. By incorporating network function virtualization in inter-data center(DC) network, we can use the network resources intelligently and deploy network services faster. However, orchestrating service function chains across multiple data centers will incur high deployment cost, including the inter-data center bandwidth cost, virtual network function cost and the intra-data center bandwidth cost. In this paper, we orchestrate SFCs across multiple data centers, with a goal to minimize the overall cost. An integer linear programming(ILP) model is formulated and we provide a meta-heuristic algorithm named GBAO which contains three modules to solve it. We implemented our algorithm in Python and performed side-by-side comparison with prior algorithms. Simulation results show that our proposed algorithm reduces the overall cost by at least 21.4% over the existing algorithms for accommodating the same service function chain requests.展开更多
Virtualization of network/service functions means time sharing network/service（and affiliated）resources in a hyper speed manner.The concept of time sharing was popularized in the 1970s with mainframe computing.The s...Virtualization of network/service functions means time sharing network/service（and affiliated）resources in a hyper speed manner.The concept of time sharing was popularized in the 1970s with mainframe computing.The same concept has recently resurfaced under the guise of cloud computing and virtualized computing.Although cloud computing was originally used in IT for server virtualization,the ICT industry is taking a new look at virtualization.This paradigm shift is shaking up the computing,storage,networking,and ser vice industries.The hope is that virtualizing and automating configuration and service management/orchestration will save both capes and opex for network transformation.A complimentary trend is the separation（over an open interface）of control and transmission.This is commonly referred to as software defined networking（SDN）.This paper reviews trends in network/service functions,efforts to standardize these functions,and required management and orchestration.展开更多
This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendenc...This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendency to increase and that its ecological service function is to be improved with stand age growing. The species diversity in forest communities is also gradually increased on different succession stage till reaching a climax level. But the species diversity in the climax community is slightly decreased before it reaches a relatively constant status. Ecological service function of diversity is gradually strengthened with the progress of succession. In addition, species diversity in a stand in a similar site and at a same age differs among forest types. Species diversity index within a coniferous and broad-leaved mixed forest is larger than that within a coniferous forest. Meanwhile, species diversity enriches as the tree density increases.展开更多
This methodological investigation deals with measurement and valuation of ecological service functions for urban green space. Social, economic and ecological dimensions for such types of function were analyzed and a ...This methodological investigation deals with measurement and valuation of ecological service functions for urban green space. Social, economic and ecological dimensions for such types of function were analyzed and a concept “integrated ecological service functions” (IESF) was put forward for evaluation. Based upon this conceptual approach, an index system for measuring IESF for urban green space was established. With a methodological integration of fuzzy mathematics, decision making analysis and Delphi method, an AHP fuzzy evaluation techniques for IESF for urban green space, called AFIFUG method, was developed. Such a method has been directly applied to the land use strategic planning of Tianjin out ring green belt(TOGB), and its analysis results have been successfully put into operation.展开更多
In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated...In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated by using the method of Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008). The results showed that in 2014, the total value of forest ecosystem service function in Kanas Nature Reserve increased by 7.34% compared with that in 2009, and the value of water conservation and biodiversity accounted for the largest proportion. The increasing rate of functional value of shrub forest land was obviously higher than that of coniferous forest land and broad-leaf forest land. The service function and value of different forest types were obviously different.展开更多
In China, with the restructuring of health care system moving forward, private community health facilities have been playing a complementary but increasingly important role in providing public health and basic medical...In China, with the restructuring of health care system moving forward, private community health facilities have been playing a complementary but increasingly important role in providing public health and basic medical care services in urban areas. However, only limited evidence is available con-cerning the service functions of private community health facilities in China. The aim of this study was to explore the functions of private community health stations (PCHSs) to provide evidence-based rec-ommendations for policy-making and practice in the development of urban community health services systems. A total of 818 PCHSs and 4320 government-sponsored community health stations (GCHSs) located in 28 cities of China were investigated in 2008. The percentages of stations that provided health services and the annual workload per community health worker (CHW) were compared between the two types of institutions. The results showed that the percentages of PCHSs providing public health services were significantly higher than those of GCHSs (P<0.05); but no significant differences were found in the percentages of basic medical services providing between PCHSs and GCHSs (P>0.05). The annual workloads of all the public health services and basic medical services per CHW in PCHSs were lighter than those in GCHSs (P<0.05), except for resident health records establishment and health education materials distribution (P>0.05). At present, the GCHSs are still the mainstream in urban China, which will last for a long period in future. However, our findings showed that the annual workloads of CHWs in PCHSs were no heavier than those in GCHSs, and the PCHSs were willing to provide public health services. In view of current inadequacy of health resources in China, it is feasible to further develop PCHSs under the guidance of the government, given that PCHSs can perform the basic functions of community health services, which is useful for the formation of public-private partnerships (PPP) and the improvement of community health services.展开更多
The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of conti...The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of continuous service time,respectively.Using the statistical mechanical and asymptotic limit methods,Fokker–Planck equations are derived from the corresponding Boltzmann-type equations with non-Maxwellian collision kernels.The steady-state solutions of the Fokker–Planck equation are obtained in exact form.Numerical experiments are provided to support our results under different parameters.展开更多
Introduction: In developing countries, gender-based violence (GBV) is a real public health problem. In Benin, GBV affects the majority of women and girls (69%). Benin has implemented strategies and set up integrated c...Introduction: In developing countries, gender-based violence (GBV) is a real public health problem. In Benin, GBV affects the majority of women and girls (69%). Benin has implemented strategies and set up integrated centers for the management of violence in order to reduce cases of violence and ensure the holistic management of victims. The objective of our study was to assess the functionality of the network of sexual and reproductive health rights (SRHR) in case of GBV in the commune of Kpomasse in 2022. Method: This descriptive and evaluative study was conducted from March 21 to April 11, 2022. The sampling method used was non-probabilistic. Reasoned choice and convenience were the techniques used for the different targets of the study. The functionality of the SRHR service network was assessed first by calculating scores at the structure, process and outcome levels, and then by analysis using the human rights-based approach. Results: Out of the 34 GBV victims identified, only one had received a full response and 54% of the victims had no knowledge of SRHR. The lack of knowledge about health care facilities was 41% for victims and 80% for non-victims in the community who participated in the study. In the case of gender-based violence, the community preferred to settle out of court rather than report it. The functionality of the networking of sexual and reproductive health rights services in the event of the occurrence of gender-based violence in the commune of Kpomassè is insufficient. Lack of knowledge of the roles of rights holders (DD) and duty bearers (DO) explains the insufficient functionality of networking. Conclusion: Training of SRHR service agents and community sensitization are essential to improve the functionality of SRHR service networking in the commune of Kpomasse.展开更多
Aiming at the rapid growth of network services,which leads to the problems of long service request processing time and high deployment cost in the deployment of network function virtualization service function chain(S...Aiming at the rapid growth of network services,which leads to the problems of long service request processing time and high deployment cost in the deployment of network function virtualization service function chain(SFC)under 5G networks,this paper proposes a multi-agent deep deterministic policy gradient optimization algorithm for SFC deployment(MADDPG-SD).Initially,an optimization model is devised to enhance the request acceptance rate,minimizing the latency and deploying the cost SFC is constructed for the network resource-constrained case.Subsequently,we model the dynamic problem as a Markov decision process(MDP),facilitating adaptation to the evolving states of network resources.Finally,by allocating SFCs to different agents and adopting a collaborative deployment strategy,each agent aims to maximize the request acceptance rate or minimize latency and costs.These agents learn strategies from historical data of virtual network functions in SFCs to guide server node selection,and achieve approximately optimal SFC deployment strategies through a cooperative framework of centralized training and distributed execution.Experimental simulation results indicate that the proposed method,while simultaneously meeting performance requirements and resource capacity constraints,has effectively increased the acceptance rate of requests compared to the comparative algorithms,reducing the end-to-end latency by 4.942%and the deployment cost by 8.045%.展开更多
[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [...[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [Method] The val- ues of ecosystem function was estimated by market value method, opportunity cost approach, replacement cost method, shadow engineering approach, travel cost method, hedonic pricing method and contingent value method. [Result] With wetland ecosystem service function value totals 4.968 billion yuan, the value of eco-environ- ment regulation and maintenance was the highest, followed by the value of cultural and social function. The value of material production was the least. The values of sub-functions can be concluded by comparison of service function va}ue and pro- portions, as follows： flood mitigation 〉water purification 〉water conservation 〉 tourism＆leisure〉material production〉scientific research and education〉water supply〉 biodiversity maintenance〉regulation on atmosphere constituents. [Conclusion] The re- search performed quantitative evaluations on ecosystem service function values of wetlands in Chao Lake and is of significance for specific development and protec- tion of local wetlands.展开更多
基金financial assistance from the European Union(Contract number:AFS2023/444-387)。
文摘The Kulpawn River Basin(KRB)plays a critical role in supporting rural livelihoods through agriculture,water supply,and biodiversity conservation.However,between 1995 and 2023,significant land use and land cover(LULC)changes have been observed,affecting ecosystem services(ESs).This study evaluated the ecosystem service values(ESVs)associated with LULC changes.The random forest algorithm was applied to extract LULC information from Landsat images for 1995,2005,2015,and 2023.The benefit transfer method was employed to estimate the ESVs over the study period.Questionnaires were also used to assess the views of respondents on the drivers of the ES changes in the basin.The results showed that agricultural lands expanded by 14.14%,built-up areas by 15.17%,and light savannah forest by 8.73%,while dense savannah forest and water bodies declined by 25.71%and 20.00%,respectively.The total estimated ESV was 410.09×10^(8),362.92×10^(8),335.30×10^(8),and 319.28×10^(8) USD/(hm^(2)·a)in 1995,2005,2015,and 2023,respectively,indicating that the total ESV declined from 410.09×10^(8) USD/(hm^(2)·a)in 1995 to 319.28×10^(8) USD/(hm^(2)·a)in 2023.The study concludes that the reduction in ESVs is due to the LULC changes resulting from agricultural activities,expansion of built-up areas,population sprawl,and artisanal mining activities.Hence,there is an urgent need to develop programs and strategies to mitigate and curtail the degradation of LULC and ESVs in the basin.These findings reveal a growing ecological vulnerability,threatening water security and rural livelihoods.The study offers valuable insights to guide sustainable land use planning and ecosystem conservation strategies.
基金supported by the National Natural Science Foundation of China under Grant 62471493 and 62402257partially supported by the Natural Science Foundation of Shandong Province under Grant ZR2023LZH017,ZR2024MF066 and 2023QF025+2 种基金partially supported by the Open Research Subject of State Key Laboratory of Intelligent Game(No.ZBKF-24-12)partially supported by the Foundation of Key Laboratory of Education Informatization for Nationalities(Yunnan Normal University),the Ministry of Education(No.EIN2024C006)partially supported by the Key Laboratory of Ethnic Language Intelligent Analysis and Security Governance of MOE(No.202306).
文摘As Internet ofThings(IoT)technologies continue to evolve at an unprecedented pace,intelligent big data control and information systems have become critical enablers for organizational digital transformation,facilitating data-driven decision making,fostering innovation ecosystems,and maintaining operational stability.In this study,we propose an advanced deployment algorithm for Service Function Chaining(SFC)that leverages an enhanced Practical Byzantine Fault Tolerance(PBFT)mechanism.The main goal is to tackle the issues of security and resource efficiency in SFC implementation across diverse network settings.By integrating blockchain technology and Deep Reinforcement Learning(DRL),our algorithm not only optimizes resource utilization and quality of service but also ensures robust security during SFC deployment.Specifically,the enhanced PBFT consensus mechanism(VRPBFT)significantly reduces consensus latency and improves Byzantine node detection through the introduction of a Verifiable Random Function(VRF)and a node reputation grading model.Experimental results demonstrate that compared to traditional PBFT,the proposed VRPBFT algorithm reduces consensus latency by approximately 30%and decreases the proportion of Byzantine nodes by 40%after 100 rounds of consensus.Furthermore,the DRL-based SFC deployment algorithm(SDRL)exhibits rapid convergence during training,with improvements in long-term average revenue,request acceptance rate,and revenue/cost ratio of 17%,14.49%,and 20.35%,respectively,over existing algorithms.Additionally,the CPU resource utilization of the SDRL algorithmreaches up to 42%,which is 27.96%higher than other algorithms.These findings indicate that the proposed algorithm substantially enhances resource utilization efficiency,service quality,and security in SFC deployment.
基金supported by the Malaysia Ministry of Higher Education under Fundamental Research Grant Scheme with Project Code:FRGS/1/2024/TK07/USM/02/3.
文摘Mobile service robots(MSRs)in hospital environments require precise and robust trajectory tracking to ensure reliable operation under dynamic conditions,including model uncertainties and external disturbances.This study presents a cognitive control strategy that integrates a Numerical Feedforward Inverse Dynamic Controller(NFIDC)with a Feedback Radial Basis Function Neural Network(FRBFNN).The robot’s mechanical structure was designed in SolidWorks 2022 SP2.0 and validated under operational loads using finite element analysis in ANSYS 2022 R1.The NFIDC-FRBFNN framework merges proactive inverse dynamic compensation with adaptive neural learning to achieve smooth torque responses and accurate motion control.A two-stage simulation evaluation was conducted.In the first stage,the controller was tested in a simulated hospital environment under both ideal and non-ideal conditions.In the second,it was benchmarked against four established controllers-Neural Network Model Reference Adaptive(NNMRA),Z-number Fuzzy Logic(Z-FL),Adaptive Dynamic Controller(ADC),and Fuzzy Logic-PID(FL-PID)—using circular and lemniscate trajectories.Across ten runs,the proposed controller achieved the lowest tracking errors under all conditions.Under ideal conditions,it achieved average improvements of 55.24%,75.75%,and 55.20%in integral absolute error(IAE),integral squared error(ISE),and mean absolute error(MAE),respectively,with coefficient of variation(CV)reductions above 55%.Under non-ideal conditions,average improvements exceeded 64%in IAE,77%in ISE,and 66%in MAE,while maintaining CV reductions above 57%.These results confirm that the NFIDC-FRBFNN controller offers superior accuracy,robustness,and consistency for real-time path tracking in healthcare robotics.
基金Supported by Special Funds for Central Financial to Support the Local Colleges and Universities([2013]389)~~
文摘In order to better explore the function of urban forest in human habitation and settlement environment,the ecosystem functions were evaluated in terms of air purification,water conservation,soil conservation,maintenance of biodiversity in Meizhou by the methods of market price,shadow prices approach and opportunity cost,and the problems of the value assessment at home and abroad in urban forest ecosystem services function were simply discussed.
基金funded by National Basic Research Program of China (2013CBA01804, 2013CBA01808)Technology Services Network Program (STS-HHS Program) of Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciencesthe independent subject from Stake Key Laboratory of Cryospheric Sciences, Chinese Academy of Sciences
文摘Cryosphere science research and development(R&D) has been strongly committed to public service, integrating natural sciences with socioeconomic impacts. Owing to the current shift from purely natural cryosphere scientific research to linking cryosphere science with socioeconomic and cultural science, cross-disciplinary research in this field is emerging, which advocates future cryosphere science research in this field. Utilizing the cryosphere service function(CSF), this study establishes CSF and its value evaluation system. Cryosphere service valuation can benefit the decisionmakers' and public's awareness of environmental protection. Implementing sustainable CSF utilization strategies and macroeconomic policymaking for global environmental protection will have profound and practical significance as well as avoid environmental degradation while pursuing short-term economic profits and achieving rapid economic development.
基金This work is supported by the National Key R&D Program of China(2018YFB1800601)the Key R&D Program of Zhejiang Province(2021C01036,2020C01021)the Fundamental Research Funds for the Central Universities(Zhejiang University NGICS Platform:ZJUNGICS2021021).
文摘Service function chains(SFC)mapping takes the responsibility for managing virtual network functions(VNFs).In SFC mapping,existing solutions duplicate VNFs with redundant instances to provide high availability in response to failures.However,as a compromise,these solutions result in high resource consumption due to device maintenance.In this paper,we propose a novel method named dynamic backup sharing(DBS)that allows SFCs to dynamically share backups to reduce resource consumption.DBS formulates the problem of sharing backups among different VNFs as an integer linear programming(ILP).Thereafter,we design a novel online algorithm based on dynamic programming to solve the problem.The experimental results indicate that DBS outperforms state-ofthe-art works by reducing resource consumption and improving the number of accepted requests.
基金supported in part by NSFC of China under Grant No.61232017National Basic Research Program of China(“973 program”)under Grant No.2013CB329101+1 种基金Fundamental Research Funds for the Central Universities under Grant No.2016YJS026NSAF of China under Grant No.U1530118
文摘Software Defined Satellite Networks(SDSN) are proposed to solve the problems in traditional satellite networks, such as time-consuming configuration and inflexible traffic scheduling. The emerging application of small satellite and research of SDSN make it possible for satellite networks to provide flexible network services. Service Function Chain(SFC) can satisfy this need. In this paper, we are motivated to investigate applying SFC in the small satellite-based SDSN for service delivery. We introduce the structure of the multi-layer constellation-based SDSN. Then, we describe two deployment patterns of SFC in SDSN, the Multi-Domain(MD) pattern and the Satellite Formation(SF) pattern. We propose two algorithms, SFP-MD, and SFP-SF, to calculate the Service Function Path(SFP). We implement the algorithms and conduct contrast experiments in our prototype. Finally, we summarize the applicable conditions of two deployment patterns according to the experimental results in terms of hops, delay, and packet loss rate.
基金supported in part by the National Natural Science Foundation of China(NSFC)under grant numbers U22A2007 and 62171010the Open project of Satellite Internet Key Laboratory in 2022(Project 3:Research on Spaceborne Lightweight Core Network and Intelligent Collaboration)the Beijing Natural Science Foundation under grant number L212003.
文摘With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)satellite networks.While due to the scarcity of bandwidth resources and dynamic topology of LEO satellites,the static SFC placement schemes may cause performance degradation,resource waste and even service failure.In this paper,we consider migration and establish an online migration model,especially considering the dynamic topology.Given the scarcity of bandwidth resources,the model aims to maximize the total number of accepted SFCs while incurring as little bandwidth cost of SFC transmission and migration as possible.Due to its NP-hardness,we propose a heuristic minimized dynamic SFC migration(MDSM)algorithm that only triggers the migration procedure when new SFCs are rejected.Simulation results demonstrate that MDSM achieves a performance close to the upper bound with lower complexity.
基金This research was partially supported by the National Key Research and Development Program of China(2018YFC1507005)China Postdoctoral Science Foundation(2018M643448)+1 种基金Sichuan Science and Technology Program(2020YFG0189)Fundamental Research Funds for the Central Universities,Southwest Minzu University(2020NQN18).
文摘Animal husbandry is the pillar industry in some ethnic areas of China.However,the communication/networking infrastructure in these areas is often underdeveloped,thus the difficulty in centralized management,and challenges for the effective monitoring.Considering the dynamics of the field monitoring environment,as well as the diversity and mobility of monitoring targets,traditional WSN(Wireless Sensor Networks)or IoT(Internet of Things)is difficult to meet the surveillance needs.Mobile surveillance that features the collaboration of various functions(camera,sensing,image recognition,etc.)deployed on mobile devices is desirable in a volatile wireless environment.This paper proposes the service function chaining for mobile surveillance of animal husbandry,which orchestrates multi-path multifunction(MPMF)chains to help mobile devices to collaborate in complex surveillance tasks,provide backup chains in case the primary service function chain fails due to mobility,signal strength,obstacle,etc.,and make up for the defects of difficult deployment of monitoring facilities in ethnic areas.MPMF algorithmmodels both mobile devices and various functions deployed on them as abstract graph nodes,so that chains that are required to traverse various functions and hosting mobile devices can be orchestrated in a single graphbased query through modified and adapted Dijkstra-like algorithms,with their cost ordered automatically.Experiment results show that the proposed MPMF algorithm finds multiple least-costly chains that traverse demanded functions in a timely fashion on Raspberry Pi-equipped mobile devices.
基金Sponsored by Subsidy for the Running of National Positioning Observation Station of Forest Ecosystems in Wenchang City of Hainan Province(2015-LYPT-DW-095)
文摘Based on the measurement parameters and index in the Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008),the value of ecological service functions of ecological public welfare forest in Wenchang City was evaluated and analyzed.The results show that the total value of ecosystem service function of ecological public welfare forests in Wenchang City is about 4.020 billion yuan,of which storage capacity,water purification,soil fixation,fertilizer(N,P and K fertilizer) conservation,carbon sequestration,oxygen release,forest nutrient accumulation,providing anion,absorbing SO_2,absorbing fluoride,absorbing NxO,absorbing soil heavy metals,dust retention,noise reduction,sterilization,forest protection,forest biodiversity protection,and forest recreation(ecological tourism) are about 1.510 billion,582.256 million,3.769 million,268.220 million,116.360 million,2.747 million,22.682 million,42.817 million,1.722 million,74,600,131,900,187.918 million,77.409 million,28.721 million,43.090 million,180.696 million,571.036 million,and 108.677 million yuan
基金supported by the National Natural Science Foundation of China(61501044)
文摘Network function virtualization is a new network concept that moves network functions from dedicated hardware to software-defined applications running on standard high volume severs. In order to accomplish network services, traffic flows are usually processed by a list of network functions in sequence which is defined by service function chain. By incorporating network function virtualization in inter-data center(DC) network, we can use the network resources intelligently and deploy network services faster. However, orchestrating service function chains across multiple data centers will incur high deployment cost, including the inter-data center bandwidth cost, virtual network function cost and the intra-data center bandwidth cost. In this paper, we orchestrate SFCs across multiple data centers, with a goal to minimize the overall cost. An integer linear programming(ILP) model is formulated and we provide a meta-heuristic algorithm named GBAO which contains three modules to solve it. We implemented our algorithm in Python and performed side-by-side comparison with prior algorithms. Simulation results show that our proposed algorithm reduces the overall cost by at least 21.4% over the existing algorithms for accommodating the same service function chain requests.
文摘Virtualization of network/service functions means time sharing network/service（and affiliated）resources in a hyper speed manner.The concept of time sharing was popularized in the 1970s with mainframe computing.The same concept has recently resurfaced under the guise of cloud computing and virtualized computing.Although cloud computing was originally used in IT for server virtualization,the ICT industry is taking a new look at virtualization.This paradigm shift is shaking up the computing,storage,networking,and ser vice industries.The hope is that virtualizing and automating configuration and service management/orchestration will save both capes and opex for network transformation.A complimentary trend is the separation（over an open interface）of control and transmission.This is commonly referred to as software defined networking（SDN）.This paper reviews trends in network/service functions,efforts to standardize these functions,and required management and orchestration.
基金Supported by the Knowledge Innovation Program of Chinese Academy of Scicnces(KZCX2-SW-319-4)
文摘This paper presents a study on species diversity and its ecological service function in the plateau area in western Sichuan. The results show that species diversity in the plantations on the cutover land has a tendency to increase and that its ecological service function is to be improved with stand age growing. The species diversity in forest communities is also gradually increased on different succession stage till reaching a climax level. But the species diversity in the climax community is slightly decreased before it reaches a relatively constant status. Ecological service function of diversity is gradually strengthened with the progress of succession. In addition, species diversity in a stand in a similar site and at a same age differs among forest types. Species diversity index within a coniferous and broad-leaved mixed forest is larger than that within a coniferous forest. Meanwhile, species diversity enriches as the tree density increases.
文摘This methodological investigation deals with measurement and valuation of ecological service functions for urban green space. Social, economic and ecological dimensions for such types of function were analyzed and a concept “integrated ecological service functions” (IESF) was put forward for evaluation. Based upon this conceptual approach, an index system for measuring IESF for urban green space was established. With a methodological integration of fuzzy mathematics, decision making analysis and Delphi method, an AHP fuzzy evaluation techniques for IESF for urban green space, called AFIFUG method, was developed. Such a method has been directly applied to the land use strategic planning of Tianjin out ring green belt(TOGB), and its analysis results have been successfully put into operation.
基金Sponsored by Monitoring and Assessment of Forestry Ecological Service Function in Xinjiang(xjlk(2013)001)Open Fund of Forest Ecosystem Positioning Research Station in Altai mountain,Xinjiang
文摘In order to clarify the service function and value of forest ecosystem in Kanas Nature Reserve, the ecological service function and its value of forest ecosystem in Kanas Nature Reserve in 2009 and 2014 were evaluated by using the method of Specifications for Assessment of Forest Ecosystem Services in China(LY/T 1721-2008). The results showed that in 2014, the total value of forest ecosystem service function in Kanas Nature Reserve increased by 7.34% compared with that in 2009, and the value of water conservation and biodiversity accounted for the largest proportion. The increasing rate of functional value of shrub forest land was obviously higher than that of coniferous forest land and broad-leaf forest land. The service function and value of different forest types were obviously different.
基金supported by agrant from"The National Urban Community Health Service System Building Project"of the Ministry of Health of China(No.)
文摘In China, with the restructuring of health care system moving forward, private community health facilities have been playing a complementary but increasingly important role in providing public health and basic medical care services in urban areas. However, only limited evidence is available con-cerning the service functions of private community health facilities in China. The aim of this study was to explore the functions of private community health stations (PCHSs) to provide evidence-based rec-ommendations for policy-making and practice in the development of urban community health services systems. A total of 818 PCHSs and 4320 government-sponsored community health stations (GCHSs) located in 28 cities of China were investigated in 2008. The percentages of stations that provided health services and the annual workload per community health worker (CHW) were compared between the two types of institutions. The results showed that the percentages of PCHSs providing public health services were significantly higher than those of GCHSs (P<0.05); but no significant differences were found in the percentages of basic medical services providing between PCHSs and GCHSs (P>0.05). The annual workloads of all the public health services and basic medical services per CHW in PCHSs were lighter than those in GCHSs (P<0.05), except for resident health records establishment and health education materials distribution (P>0.05). At present, the GCHSs are still the mainstream in urban China, which will last for a long period in future. However, our findings showed that the annual workloads of CHWs in PCHSs were no heavier than those in GCHSs, and the PCHSs were willing to provide public health services. In view of current inadequacy of health resources in China, it is feasible to further develop PCHSs under the guidance of the government, given that PCHSs can perform the basic functions of community health services, which is useful for the formation of public-private partnerships (PPP) and the improvement of community health services.
基金the Special Project of Yili Normal University(to improve comprehensive strength of disciplines)(Grant No.22XKZZ18)Yili Normal University Scientific Research Innovation Team Plan Project(Grant No.CXZK2021015)Yili Science and Technology Planning Project(Grant No.YZ2022B036).
文摘The distribution of continuous service time in call centers is investigated.A non-Maxwellian collision kernel combining two different value functions in the interaction rule are used to describe the evolution of continuous service time,respectively.Using the statistical mechanical and asymptotic limit methods,Fokker–Planck equations are derived from the corresponding Boltzmann-type equations with non-Maxwellian collision kernels.The steady-state solutions of the Fokker–Planck equation are obtained in exact form.Numerical experiments are provided to support our results under different parameters.
文摘Introduction: In developing countries, gender-based violence (GBV) is a real public health problem. In Benin, GBV affects the majority of women and girls (69%). Benin has implemented strategies and set up integrated centers for the management of violence in order to reduce cases of violence and ensure the holistic management of victims. The objective of our study was to assess the functionality of the network of sexual and reproductive health rights (SRHR) in case of GBV in the commune of Kpomasse in 2022. Method: This descriptive and evaluative study was conducted from March 21 to April 11, 2022. The sampling method used was non-probabilistic. Reasoned choice and convenience were the techniques used for the different targets of the study. The functionality of the SRHR service network was assessed first by calculating scores at the structure, process and outcome levels, and then by analysis using the human rights-based approach. Results: Out of the 34 GBV victims identified, only one had received a full response and 54% of the victims had no knowledge of SRHR. The lack of knowledge about health care facilities was 41% for victims and 80% for non-victims in the community who participated in the study. In the case of gender-based violence, the community preferred to settle out of court rather than report it. The functionality of the networking of sexual and reproductive health rights services in the event of the occurrence of gender-based violence in the commune of Kpomassè is insufficient. Lack of knowledge of the roles of rights holders (DD) and duty bearers (DO) explains the insufficient functionality of networking. Conclusion: Training of SRHR service agents and community sensitization are essential to improve the functionality of SRHR service networking in the commune of Kpomasse.
基金The financial support fromthe Major Science and Technology Programs inHenan Province(Grant No.241100210100)National Natural Science Foundation of China(Grant No.62102372)+3 种基金Henan Provincial Department of Science and Technology Research Project(Grant No.242102211068)Henan Provincial Department of Science and Technology Research Project(Grant No.232102210078)the Stabilization Support Program of The Shenzhen Science and Technology Innovation Commission(Grant No.20231130110921001)the Key Scientific Research Project of Higher Education Institutions of Henan Province(Grant No.24A520042)is acknowledged.
文摘Aiming at the rapid growth of network services,which leads to the problems of long service request processing time and high deployment cost in the deployment of network function virtualization service function chain(SFC)under 5G networks,this paper proposes a multi-agent deep deterministic policy gradient optimization algorithm for SFC deployment(MADDPG-SD).Initially,an optimization model is devised to enhance the request acceptance rate,minimizing the latency and deploying the cost SFC is constructed for the network resource-constrained case.Subsequently,we model the dynamic problem as a Markov decision process(MDP),facilitating adaptation to the evolving states of network resources.Finally,by allocating SFCs to different agents and adopting a collaborative deployment strategy,each agent aims to maximize the request acceptance rate or minimize latency and costs.These agents learn strategies from historical data of virtual network functions in SFCs to guide server node selection,and achieve approximately optimal SFC deployment strategies through a cooperative framework of centralized training and distributed execution.Experimental simulation results indicate that the proposed method,while simultaneously meeting performance requirements and resource capacity constraints,has effectively increased the acceptance rate of requests compared to the comparative algorithms,reducing the end-to-end latency by 4.942%and the deployment cost by 8.045%.
基金Supported by Anhui Environment Protection Scientific Research Program in 2014(201404)~~
文摘[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [Method] The val- ues of ecosystem function was estimated by market value method, opportunity cost approach, replacement cost method, shadow engineering approach, travel cost method, hedonic pricing method and contingent value method. [Result] With wetland ecosystem service function value totals 4.968 billion yuan, the value of eco-environ- ment regulation and maintenance was the highest, followed by the value of cultural and social function. The value of material production was the least. The values of sub-functions can be concluded by comparison of service function va}ue and pro- portions, as follows： flood mitigation 〉water purification 〉water conservation 〉 tourism＆leisure〉material production〉scientific research and education〉water supply〉 biodiversity maintenance〉regulation on atmosphere constituents. [Conclusion] The re- search performed quantitative evaluations on ecosystem service function values of wetlands in Chao Lake and is of significance for specific development and protec- tion of local wetlands.
