During the construction of multifunctional landscape(MFL) actor-network, economic, social, and ecological functions presented significant differences, which resulted from the different roles and effects of various het...During the construction of multifunctional landscape(MFL) actor-network, economic, social, and ecological functions presented significant differences, which resulted from the different roles and effects of various heterogeneous actors according to the tourism experience. In Hekou Village at the border area between China and North Korea, the roles and effects of heterogeneous actors during the MFL actor-network construction were analyzed by means of the analytic network process(ANP), which verified the Groundings-Entrepreneurship-Markets(GEM) theoretical framework of the MFL actor-network that assumed tourism experiences were core actors, and economic, social, and ecological landscape actors acted as support. Research results showed that in the MFL actornetwork construction, social and economic functions of landscapes were strong, while ecological and tourism experience functions were weak and that folk customs and land utilization were key actors of the MFL actor-network construction. In the MFL actor-network construction, actors played different roles and had different effects on the network. Intelligence facilities and rurality were critical to drive the MFL actor network translation process and pass through "obligatory passage point". By changing the interaction mode and intensity of the actors, the MFL actor-network could be promoted.展开更多
Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacki...Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacking communication infrastructure.Unmanned aerial vehicle(UAV)offers a novel solution for WSN data collection,leveraging their high mobility.In this paper,we present an efficient UAV-assisted data collection algorithm aimed at minimizing the overall power consumption of the WSN.Firstly,a two-layer UAV-assisted data collection model is introduced,including the ground and aerial layers.The ground layer senses the environmental data by the cluster members(CMs),and the CMs transmit the data to the cluster heads(CHs),which forward the collected data to the UAVs.The aerial network layer consists of multiple UAVs that collect,store,and forward data from the CHs to the data center for analysis.Secondly,an improved clustering algorithm based on K-Means++is proposed to optimize the number and locations of CHs.Moreover,an Actor-Critic based algorithm is introduced to optimize the UAV deployment and the association with CHs.Finally,simulation results verify the effectiveness of the proposed algorithms.展开更多
Actors'relocation is utilized during the network initialization to enhance real-time performance of wireless sensor and actor networks(WSANs)which is an important issue of WSANs.The actor deployment problem in WSA...Actors'relocation is utilized during the network initialization to enhance real-time performance of wireless sensor and actor networks(WSANs)which is an important issue of WSANs.The actor deployment problem in WSANs is proved NP-Hard whether the amount of actors is redundant or not,but to the best of our knowledge,no effective distributed algorithms in previous research can solve the problem.Thus two actor deployment strategies which need not the boundary control compared with present deployment strategies are proposed to solve this problem approximately based on the Voronoi diagram.Through simulation experiment,the results show that our distributed strategies are more effective than the present deployment strategies in terms of real-time performance,convergence time and energy consumption.展开更多
Objective To investigate the chemical compositions of Maxing Shigan Decoction(麻杏石甘汤,MXSGD)and elucidate its anti-influenza A virus(IAV)mechanism from prediction to validation.Methods Ultra high-performance liquid...Objective To investigate the chemical compositions of Maxing Shigan Decoction(麻杏石甘汤,MXSGD)and elucidate its anti-influenza A virus(IAV)mechanism from prediction to validation.Methods Ultra high-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)was employed to analyze the chemical compositions of MXSGD.Network pharmacology theories were used to screen and identify shared targets of both the potential targets of active ingredients of MXSGD and IAV.A protein-protein interaction(PPI)network was then constructed,followed by Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses.The binding stability between core bioactive compounds and key targets was validated by molecular docking and dynamic simulations.A total of 24 BALB/c mice were infected with IAV to build IAV mouse models.After successful modelling,the mouse models were randomly divided into model,MXSGD high-dose(2.8 g/kg),MXSGD low-dose(1.4 g/kg),and oseltamivir(20.14 mg/kg)groups,with an additional normal mice as control group(n=6 per group).The treatments were administered by gavage daily between 8:00 a.m.and 10:00 a.m.for five consecutive days.Upon completion of the administration,the body weight ratio,lung index,protein content in the bronchoalveolar lavage fluid(BALF),and the levels of inflammatory factors including interleukin(IL)-6 and tumor necrosis factor(TNF)-αin mice were measured to preliminarily analyze the therapeutic efficacy of MXSGD against IAV infection.Furthermore,the expression levels of mechanistic target of rapamycin(mTOR),hypoxia inducible factor(HIF)-1α,and vascular endothelial growth factor(VEGF)proteins in the HIF-1 signaling pathway,which was enriched by network pharmacology,were detected by Western blot.Results A total of 212 chemical components in MXSGD were identified by the UPLC-MS/MS method.These chemical components can be classified into 9 primary categories and 31 secondary categories.After intersecting the chemical component targets with IAV-related targets,a total of 567 potential MXSGD components targeting IAV were identified.The construction of PPI network and the results of both GO and KEGG enrichment analyses revealed that the anti-IAV effects of MXSGD were associated with multiple pathways,including apoptosis,TNF,HIF-1,and IL-17 signaling pathways.The results of molecular docking demonstrated that the binding energies between the core compound 1-methoxyphaseollin and key targets including HIF-1α,mTOR,and VEGF were all lower than–5.0 kcal/mol.Furthermore,molecular dynamics simulations confirmed the structural stability of the resulting complexes.Animal experiments showed that compared with the normal controls,IAV-infected mice showed significantly reduced body weight ratio,markedly increased lung index,protein content in BALF,and the levels of inflammatory factors such as IL-6 and TNF-α(P<0.01),thereby causing damage to the lung tissue;consequently,the expression levels of mTOR,HIF-1α,and VEGF proteins in the lung tissues of these mice were significantly elevated(P<0.01).However,after MXSGD treatment,the mouse models presented a significant increase in body weight ratio,as well as marked decreases in lung index,protein content in BALF,and the levels of inflammatory factors including IL-6 and TNF-α(P<0.01).Furthermore,the therapy alleviated IAV-induced injuries and significantly downregulated the expression levels of mTOR,HIF-1α,and VEGF proteins in lung tissues(P<0.01 or P<0.05).Conclusion MXSGD exerts anti-IAV effects through multi-component,multi-target,and multi-pathway synergism.Among them,1-methoxyphaseollin is identified as a potential key component,which alleviates virus-induced lung injury and inflammatory response via the regulation of HIF-1 signaling pathway,providing experimental evidence for the clinical application of MXSGD.展开更多
The relationship between literature and society has been a subject of continuous exploration since the inception of literature itself.On the one hand,from Plato’s theory of mimesis onward,literature has consistently ...The relationship between literature and society has been a subject of continuous exploration since the inception of literature itself.On the one hand,from Plato’s theory of mimesis onward,literature has consistently been viewed as a representation of social reality,positioning literature as subordinate to society.On the other hand,with the rise of structuralism and the New Criticism,certain schools of thought have focused exclusively on literature itself,deliberately overlooking the complex connections between literature and society.The growing tension between these two perspectives has increasingly placed contemporary literary studies in a polarized state,leading to a crisis in the legitimacy of literary scholarship.In response to this,Rita Felski’s exploration of the uses of literature embodies a new literary sociology that offers a way out of the current impasse in literary studies.展开更多
In the study of intelligent space oriented to home service robot, an important technology is how to construct an communication network which has the characters of high reliability and easy building. In this paper, bas...In the study of intelligent space oriented to home service robot, an important technology is how to construct an communication network which has the characters of high reliability and easy building. In this paper, based on the characteristics of ZigBee protocol, ZigBee technology is used to construct a wireless sensor and actor network. Several intelligent services based on ZigBee wireless sensor and actor network are shown to certify the reliability of this communication network. ZigBee wireless sensor and actor network builds an information bridge for the components in the intelligent space, the spatially distributed devices are connected together seamlessly. With this network, robot can share the mass information in the intelligent space and improve its performance with 'light-packs', devices in intelligent space, such as lamp, curtain can be controlled autonomously.展开更多
It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical fra...It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical framework for the study of RST.Taking two typical villages with different transition paths in rural areas of North China Plain as examples,this paper reveals the mechanism of RST and makes a comparative analysis.The results show that:1)after identifying problems and obligatory passage point,key actors recruit heterogeneous actors into the actor network by entrusting them with common interests,and realize RST under the system operation.2)Rural settlements under different transition paths have similarities in the problems to be solved,collective actions and policy factors,but there are differences in the transition process,mechanism and effect.The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough.In contrast,the degree of RST of retention development path is limited if there is no resource and location advantage.3)Based on the applicable conditions of different paths,this paper designs a logical framework of‘Situation-Structure-Behavior-Result’to scientifically guide the identification of RST paths under the background of rural revitalization.展开更多
Ground subsidence is one of the key factors damaging transportation facilities, e.g., road networks consisting of highways and railways. In this paper, we propose to apply the persistent scatterer synthetic aperture r...Ground subsidence is one of the key factors damaging transportation facilities, e.g., road networks consisting of highways and railways. In this paper, we propose to apply the persistent scatterer synthetic aperture radar interferometry （PS-InSAR） approach that uses high- resolution TerraSAR-X （TSX） imagery to extract the regional scale subsidence rates （i.e., average annual sub- sidence in mm/year） along road networks. The primary procedures involve interferometric pair selection, interfer- ogram generation, persistent scatterer （PS） detection, PS networking, phase parameterization, and subsidence rate estimation. The Xiqing District in southwest Tianjin （China） is selected as the study area. This district contains one railway line and several highway lines. A total of 15 TSX images covering this area between April 2009 and June 2010 are utilized to obtain the subsidence rates by using the PS-InSAR （PSI） approach. The subsidence rates derived from PSI range from -68.7 to -1.3 mm/year. These findings show a significantly uneven subsidence pattern along the road network. Comparison between the PSI-derived subsidence rates and the leveling data obtained along the highways shows that the mean and standard deviation （SD） of the discrepancies between the two types of subsidence rates are 0.1 and 4-3.2 mm/year, respectively. The results indicate that the high-resolution TSX PSI is capable of providing comprehensive and detailed subsidence information regarding road networks with millimeter-level accuracy. Further inspections under geo- logical conditions and land-use categories in the study area indicate that the observed subsidence is highly related to aquifer compression due to groundwater pumping. Therefore, measures should be taken to mitigate groundwater extraction for the study area.展开更多
Hot compression experiments were conducted on Ti 15 3 alloy specimens using Gleeble 1500 Thermal Simulator.These tests were focused to obtain the flow stress data under various conditions of strain,strain rate and tem...Hot compression experiments were conducted on Ti 15 3 alloy specimens using Gleeble 1500 Thermal Simulator.These tests were focused to obtain the flow stress data under various conditions of strain,strain rate and temperature. On the basis of these data, the predicting model for the nonlinear relation between flow stress and deformation strain,strain rate and temperature for Ti 15 3 alloy was developed with a back propagation artificial neural network method. Results show that the neural network can reproduce the flow stress in the sampled data and predict the nonsampled data well. Thus the neural network method has been verified to be used to tackle hot deformation problems of Ti 15 3 alloy. [展开更多
This paper provides an analytic performance evaluation of dual-hop cognitive amplify-and-forward (AF) relaying networks over independent nonidentically distributed (i.n.i.d.) fading channels. Two different transmit po...This paper provides an analytic performance evaluation of dual-hop cognitive amplify-and-forward (AF) relaying networks over independent nonidentically distributed (i.n.i.d.) fading channels. Two different transmit power constraint strategies at the secondary network are proposed to investigate the performance of the secondary network. In the case of combined power constraint,the maximum tolerable interference power on the primary network and the maximum transmit power at the secondary network are considered. Closed-form lower bound and its asymptotic expression for the outage probability (OP) are achieved. Utilizing the above results,average symbol error probability (ABEP) at high signal-to-noise ratios (SNRs) are also derived. In order to further study the performance of dual-hop cognitive AF relaying networks,the Closed-form lower bounds and asymptotic expressions for OP with single power constraint of the tolerable interference on the primary network is also obtained. Both analytical and simulation are employed to validate the accuracy of the theoretical analysis. The results show that the secondary network obtains a better performance when higher power constraint is employed.展开更多
Considering wireless sensor network characteristics,this paper uses network simulator,version2(NS-2)algorithm to improve Ad hoc on-demand distance vector(AODV)routing algorithm,so that it can be applied to wireless se...Considering wireless sensor network characteristics,this paper uses network simulator,version2(NS-2)algorithm to improve Ad hoc on-demand distance vector(AODV)routing algorithm,so that it can be applied to wireless sensor networks.After studying AODV routing protocol,a new algorithm called Must is brought up.This paper introduces the background and algorithm theory of Must,and discusses the details about how to implement Must algorithm.At last,using network simulator(NS-2),the performance of Must is evaluated and compared with that of AODV.Simulation results show that the network using Must algorithm has perfect performance.展开更多
基金Sponsored by the National Social Science Fund of China(15BGL118)
文摘During the construction of multifunctional landscape(MFL) actor-network, economic, social, and ecological functions presented significant differences, which resulted from the different roles and effects of various heterogeneous actors according to the tourism experience. In Hekou Village at the border area between China and North Korea, the roles and effects of heterogeneous actors during the MFL actor-network construction were analyzed by means of the analytic network process(ANP), which verified the Groundings-Entrepreneurship-Markets(GEM) theoretical framework of the MFL actor-network that assumed tourism experiences were core actors, and economic, social, and ecological landscape actors acted as support. Research results showed that in the MFL actornetwork construction, social and economic functions of landscapes were strong, while ecological and tourism experience functions were weak and that folk customs and land utilization were key actors of the MFL actor-network construction. In the MFL actor-network construction, actors played different roles and had different effects on the network. Intelligence facilities and rurality were critical to drive the MFL actor network translation process and pass through "obligatory passage point". By changing the interaction mode and intensity of the actors, the MFL actor-network could be promoted.
基金supported by the National Natural Science Foundation of China(NSFC)(61831002,62001076)the General Program of Natural Science Foundation of Chongqing(No.CSTB2023NSCQ-MSX0726,No.cstc2020jcyjmsxmX0878).
文摘Wireless Sensor Network(WSN)is widely utilized in large-scale distributed unmanned detection scenarios due to its low cost and flexible installation.However,WSN data collection encounters challenges in scenarios lacking communication infrastructure.Unmanned aerial vehicle(UAV)offers a novel solution for WSN data collection,leveraging their high mobility.In this paper,we present an efficient UAV-assisted data collection algorithm aimed at minimizing the overall power consumption of the WSN.Firstly,a two-layer UAV-assisted data collection model is introduced,including the ground and aerial layers.The ground layer senses the environmental data by the cluster members(CMs),and the CMs transmit the data to the cluster heads(CHs),which forward the collected data to the UAVs.The aerial network layer consists of multiple UAVs that collect,store,and forward data from the CHs to the data center for analysis.Secondly,an improved clustering algorithm based on K-Means++is proposed to optimize the number and locations of CHs.Moreover,an Actor-Critic based algorithm is introduced to optimize the UAV deployment and the association with CHs.Finally,simulation results verify the effectiveness of the proposed algorithms.
基金Supported by the National Natural Science Foundation of China(No.60803148,60973124)
文摘Actors'relocation is utilized during the network initialization to enhance real-time performance of wireless sensor and actor networks(WSANs)which is an important issue of WSANs.The actor deployment problem in WSANs is proved NP-Hard whether the amount of actors is redundant or not,but to the best of our knowledge,no effective distributed algorithms in previous research can solve the problem.Thus two actor deployment strategies which need not the boundary control compared with present deployment strategies are proposed to solve this problem approximately based on the Voronoi diagram.Through simulation experiment,the results show that our distributed strategies are more effective than the present deployment strategies in terms of real-time performance,convergence time and energy consumption.
基金Natural Science Foundation of Hunan Province(2025JJ80078)Open Fund of Hunan University of Chinese Medicine(21PTKF1005)。
文摘Objective To investigate the chemical compositions of Maxing Shigan Decoction(麻杏石甘汤,MXSGD)and elucidate its anti-influenza A virus(IAV)mechanism from prediction to validation.Methods Ultra high-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)was employed to analyze the chemical compositions of MXSGD.Network pharmacology theories were used to screen and identify shared targets of both the potential targets of active ingredients of MXSGD and IAV.A protein-protein interaction(PPI)network was then constructed,followed by Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses.The binding stability between core bioactive compounds and key targets was validated by molecular docking and dynamic simulations.A total of 24 BALB/c mice were infected with IAV to build IAV mouse models.After successful modelling,the mouse models were randomly divided into model,MXSGD high-dose(2.8 g/kg),MXSGD low-dose(1.4 g/kg),and oseltamivir(20.14 mg/kg)groups,with an additional normal mice as control group(n=6 per group).The treatments were administered by gavage daily between 8:00 a.m.and 10:00 a.m.for five consecutive days.Upon completion of the administration,the body weight ratio,lung index,protein content in the bronchoalveolar lavage fluid(BALF),and the levels of inflammatory factors including interleukin(IL)-6 and tumor necrosis factor(TNF)-αin mice were measured to preliminarily analyze the therapeutic efficacy of MXSGD against IAV infection.Furthermore,the expression levels of mechanistic target of rapamycin(mTOR),hypoxia inducible factor(HIF)-1α,and vascular endothelial growth factor(VEGF)proteins in the HIF-1 signaling pathway,which was enriched by network pharmacology,were detected by Western blot.Results A total of 212 chemical components in MXSGD were identified by the UPLC-MS/MS method.These chemical components can be classified into 9 primary categories and 31 secondary categories.After intersecting the chemical component targets with IAV-related targets,a total of 567 potential MXSGD components targeting IAV were identified.The construction of PPI network and the results of both GO and KEGG enrichment analyses revealed that the anti-IAV effects of MXSGD were associated with multiple pathways,including apoptosis,TNF,HIF-1,and IL-17 signaling pathways.The results of molecular docking demonstrated that the binding energies between the core compound 1-methoxyphaseollin and key targets including HIF-1α,mTOR,and VEGF were all lower than–5.0 kcal/mol.Furthermore,molecular dynamics simulations confirmed the structural stability of the resulting complexes.Animal experiments showed that compared with the normal controls,IAV-infected mice showed significantly reduced body weight ratio,markedly increased lung index,protein content in BALF,and the levels of inflammatory factors such as IL-6 and TNF-α(P<0.01),thereby causing damage to the lung tissue;consequently,the expression levels of mTOR,HIF-1α,and VEGF proteins in the lung tissues of these mice were significantly elevated(P<0.01).However,after MXSGD treatment,the mouse models presented a significant increase in body weight ratio,as well as marked decreases in lung index,protein content in BALF,and the levels of inflammatory factors including IL-6 and TNF-α(P<0.01).Furthermore,the therapy alleviated IAV-induced injuries and significantly downregulated the expression levels of mTOR,HIF-1α,and VEGF proteins in lung tissues(P<0.01 or P<0.05).Conclusion MXSGD exerts anti-IAV effects through multi-component,multi-target,and multi-pathway synergism.Among them,1-methoxyphaseollin is identified as a potential key component,which alleviates virus-induced lung injury and inflammatory response via the regulation of HIF-1 signaling pathway,providing experimental evidence for the clinical application of MXSGD.
文摘The relationship between literature and society has been a subject of continuous exploration since the inception of literature itself.On the one hand,from Plato’s theory of mimesis onward,literature has consistently been viewed as a representation of social reality,positioning literature as subordinate to society.On the other hand,with the rise of structuralism and the New Criticism,certain schools of thought have focused exclusively on literature itself,deliberately overlooking the complex connections between literature and society.The growing tension between these two perspectives has increasingly placed contemporary literary studies in a polarized state,leading to a crisis in the legitimacy of literary scholarship.In response to this,Rita Felski’s exploration of the uses of literature embodies a new literary sociology that offers a way out of the current impasse in literary studies.
文摘提出一种基于模糊RBF网络的自适应模糊A ctor-C ritic学习.采用一个模糊RBF神经网络同时逼近A ctor的动作函数和C ritic的值函数,解决状态空间泛化中易出现的“维数灾”问题.模糊RBF网络能够根据环境状态和被控对象特性的变化进行网络结构和参数的自适应学习,使得网络结构更加紧凑,整个模糊A ctor-C ritic学习具有泛化性能好、控制结构简单和学习效率高的特点.M oun ta in C ar的仿真结果验证了所提方法的有效性.
基金supported in part by National Basic Research Program of China(973 Program)(2010CB731803)National Natural Science Foundation of China(61375105)+2 种基金China Postdoctoral Science Foundation Funded Project(2015M570235)Youth Foundation of Hebei Educational Committee(QN2015187)Science Foundation of Yanshan University(B832,14LGA010)
文摘In the study of intelligent space oriented to home service robot, an important technology is how to construct an communication network which has the characters of high reliability and easy building. In this paper, based on the characteristics of ZigBee protocol, ZigBee technology is used to construct a wireless sensor and actor network. Several intelligent services based on ZigBee wireless sensor and actor network are shown to certify the reliability of this communication network. ZigBee wireless sensor and actor network builds an information bridge for the components in the intelligent space, the spatially distributed devices are connected together seamlessly. With this network, robot can share the mass information in the intelligent space and improve its performance with 'light-packs', devices in intelligent space, such as lamp, curtain can be controlled autonomously.
基金Under the auspices of the Taishan Scholars Project Special FundsNational Natural Science Fundation of China(No.42077434,42001199)Youth Innovation Technology Project of Higher School in Shandong Province(No.2019RWG016)。
文摘It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical framework for the study of RST.Taking two typical villages with different transition paths in rural areas of North China Plain as examples,this paper reveals the mechanism of RST and makes a comparative analysis.The results show that:1)after identifying problems and obligatory passage point,key actors recruit heterogeneous actors into the actor network by entrusting them with common interests,and realize RST under the system operation.2)Rural settlements under different transition paths have similarities in the problems to be solved,collective actions and policy factors,but there are differences in the transition process,mechanism and effect.The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough.In contrast,the degree of RST of retention development path is limited if there is no resource and location advantage.3)Based on the applicable conditions of different paths,this paper designs a logical framework of‘Situation-Structure-Behavior-Result’to scientifically guide the identification of RST paths under the background of rural revitalization.
基金supported by the National Basic Research Program of China(973 Program)under Grant 2012CB719901the National Natural Science Foundation of China under Grant 41074005the 2013 Doctoral Innovation Funds of Southwest Jiaotong University
文摘Ground subsidence is one of the key factors damaging transportation facilities, e.g., road networks consisting of highways and railways. In this paper, we propose to apply the persistent scatterer synthetic aperture radar interferometry （PS-InSAR） approach that uses high- resolution TerraSAR-X （TSX） imagery to extract the regional scale subsidence rates （i.e., average annual sub- sidence in mm/year） along road networks. The primary procedures involve interferometric pair selection, interfer- ogram generation, persistent scatterer （PS） detection, PS networking, phase parameterization, and subsidence rate estimation. The Xiqing District in southwest Tianjin （China） is selected as the study area. This district contains one railway line and several highway lines. A total of 15 TSX images covering this area between April 2009 and June 2010 are utilized to obtain the subsidence rates by using the PS-InSAR （PSI） approach. The subsidence rates derived from PSI range from -68.7 to -1.3 mm/year. These findings show a significantly uneven subsidence pattern along the road network. Comparison between the PSI-derived subsidence rates and the leveling data obtained along the highways shows that the mean and standard deviation （SD） of the discrepancies between the two types of subsidence rates are 0.1 and 4-3.2 mm/year, respectively. The results indicate that the high-resolution TSX PSI is capable of providing comprehensive and detailed subsidence information regarding road networks with millimeter-level accuracy. Further inspections under geo- logical conditions and land-use categories in the study area indicate that the observed subsidence is highly related to aquifer compression due to groundwater pumping. Therefore, measures should be taken to mitigate groundwater extraction for the study area.
文摘Hot compression experiments were conducted on Ti 15 3 alloy specimens using Gleeble 1500 Thermal Simulator.These tests were focused to obtain the flow stress data under various conditions of strain,strain rate and temperature. On the basis of these data, the predicting model for the nonlinear relation between flow stress and deformation strain,strain rate and temperature for Ti 15 3 alloy was developed with a back propagation artificial neural network method. Results show that the neural network can reproduce the flow stress in the sampled data and predict the nonsampled data well. Thus the neural network method has been verified to be used to tackle hot deformation problems of Ti 15 3 alloy. [
基金National Natural Science Foundation of China(No.61461024)
文摘This paper provides an analytic performance evaluation of dual-hop cognitive amplify-and-forward (AF) relaying networks over independent nonidentically distributed (i.n.i.d.) fading channels. Two different transmit power constraint strategies at the secondary network are proposed to investigate the performance of the secondary network. In the case of combined power constraint,the maximum tolerable interference power on the primary network and the maximum transmit power at the secondary network are considered. Closed-form lower bound and its asymptotic expression for the outage probability (OP) are achieved. Utilizing the above results,average symbol error probability (ABEP) at high signal-to-noise ratios (SNRs) are also derived. In order to further study the performance of dual-hop cognitive AF relaying networks,the Closed-form lower bounds and asymptotic expressions for OP with single power constraint of the tolerable interference on the primary network is also obtained. Both analytical and simulation are employed to validate the accuracy of the theoretical analysis. The results show that the secondary network obtains a better performance when higher power constraint is employed.
文摘Considering wireless sensor network characteristics,this paper uses network simulator,version2(NS-2)algorithm to improve Ad hoc on-demand distance vector(AODV)routing algorithm,so that it can be applied to wireless sensor networks.After studying AODV routing protocol,a new algorithm called Must is brought up.This paper introduces the background and algorithm theory of Must,and discusses the details about how to implement Must algorithm.At last,using network simulator(NS-2),the performance of Must is evaluated and compared with that of AODV.Simulation results show that the network using Must algorithm has perfect performance.
