Intake system of diesel engine is a strong nonlinear system, and it is difficult to establish accurate model of intake system; and bias fault and precision degradation fault of MAP of diesel engine can't be diagnosed...Intake system of diesel engine is a strong nonlinear system, and it is difficult to establish accurate model of intake system; and bias fault and precision degradation fault of MAP of diesel engine can't be diagnosed easily using model-based methods. Thus, a fault diagnosis method based on Elman neural network observer is proposed. By comparing simulation results of intake pressure based on BP network and Elman neural network, lower sampling error magnitude is gained using Elman neural network, and the error is less volatile. Forecast accuracy is between 0.015?0.017 5 and sample error is controlled within 0?0.07. Considering the output stability and complexity of solving comprehensively, Elman neural network with a single hidden layer and with 44 nodes is presented as intake system observer. By comparing the relations of confidence intervals of the residual value between the measured and predicted values, error variance and failures in various fault types. Then four typical MAP faults of diesel engine can be diagnosed: complete failure fault, bias fault, precision degradation fault and drift fault. The simulation results show: intake pressure is observable and selection of diagnostic strategy parameter reasonably can increase the accuracy of diagnosis;the proposed fault diagnosis method only depends on data and structural parameters of observer, not depends on the nonlinear model of air intake system. A fault diagnosis method is proposed not depending system model to observe intake pressure, and bias fault and precision degradation fault of MAP of diesel engine can be diagnosed based on residuals.展开更多
Purpose:With the availability and utilization of Inter-Country Input-Output(ICIO)tables,it is possible to construct quantitative indices to assess its impact on the Global Value Chain(GVC).For the sake of visualizatio...Purpose:With the availability and utilization of Inter-Country Input-Output(ICIO)tables,it is possible to construct quantitative indices to assess its impact on the Global Value Chain(GVC).For the sake of visualization,ICIO networks with tremendous low-weight edges are too dense to show the substantial structure.These redundant edges,inevitably make the network data full of noise and eventually exert negative effects on Social Network Analysis(SNA).In this case,we need a method to filter such edges and obtain a sparser network with only the meaningful connections.Design/methodology/approach:In this paper,we propose two parameterless pruning algorithms from the global and local perspectives respectively,then the performance of them is examined using the ICIO table from different databases.Findings:The Searching Paths(SP)method extracts the strongest association paths from the global perspective,while Filtering Edges(FE)method captures the key links according to the local weight ratio.The results show that the FE method can basically include the SP method and become the best solution for the ICIO networks.Research limitations:There are still two limitations in this research.One is that the computational complexity may increase rapidly while processing the large-scale networks,so the proposed method should be further improved.The other is that much more empirical networks should be introduced to testify the scientificity and practicability of our methodology.Practical implications:The network pruning methods we proposed will promote the analysis of the ICIO network,in terms of community detection,link prediction,and spatial econometrics,etc.Also,they can be applied to many other complex networks with similar characteristics.Originality/value:This paper improves the existing research from two aspects,namely,considering the heterogeneity of weights and avoiding the interference of parameters.Therefore,it provides a new idea for the research of network backbone extraction.展开更多
Under the background of constructing harmonious economic society, how to realize the coordinated development of regions in the course of region integration is a key problem. According to the relevant theory of enterpr...Under the background of constructing harmonious economic society, how to realize the coordinated development of regions in the course of region integration is a key problem. According to the relevant theory of enterprise gene reconfiguration and enterprise value network construction, we analyzed the problems in the merging course between the value network construction and region economic growth. Finally, we put forward the basic path of coordinated development of regions.展开更多
Services may be investigated from many perspectives. They encapsulate over 65% of global business, yet many gaps in the services knowledge base exist – particularly from areas including information technology, oper...Services may be investigated from many perspectives. They encapsulate over 65% of global business, yet many gaps in the services knowledge base exist – particularly from areas including information technology, operational, customer targeting, and services provision. This research investigates an emerging and truly disruptive business scenario – the service value network, from a marketing, an operations and services approach. The service value network is defined as the flexible, dynamic, delivery of a service, or product, by a business’s coordinated value chains (supply chains and demand chains working in harmony), such that a value-adding, specific, service solution is effectively, and efficiently, delivered to the individual customer. The ‘physical and virtual service value network customer – business encounter model’ is developed. Impediments to the development of a service value networks are investigated. Eight key areas related to website customer encounters are offered as investigation areas. The customer ‘touch-points’ across the virtual service encounter offers a raft of new research possibilities and possible new pathways to competitive advantage. Approaches to measure service network encounter effectors are explained. Current and future areas of business research are described. This paper frames the research agenda for service value networks.展开更多
In an unmanned aerial vehicle ad-hoc network(UANET),sparse and rapidly mobile unmanned aerial vehicles(UAVs)/nodes can dynamically change the UANET topology.This may lead to UANET service performance issues.In this st...In an unmanned aerial vehicle ad-hoc network(UANET),sparse and rapidly mobile unmanned aerial vehicles(UAVs)/nodes can dynamically change the UANET topology.This may lead to UANET service performance issues.In this study,for planning rapidly changing UAV swarms,we propose a dynamic value iteration network(DVIN)model trained using the episodic Q-learning method with the connection information of UANETs to generate a state value spread function,which enables UAVs/nodes to adapt to novel physical locations.We then evaluate the performance of the DVIN model and compare it with the non-dominated sorting genetic algorithm II and the exhaustive method.Simulation results demonstrate that the proposed model significantly reduces the decisionmaking time for UAV/node path planning with a high average success rate.展开更多
Modeling a business to match its customer perceived (and customer desired) outcomes, remains an on-going task. This paper considers shows how a service value networks (SVNs) approach may be engaged to model, and d...Modeling a business to match its customer perceived (and customer desired) outcomes, remains an on-going task. This paper considers shows how a service value networks (SVNs) approach may be engaged to model, and deliver, understanding of the front-end business and its direct engagement with its immediate (or front-end) customers. These front-end customers may be either: (1) its off-line, in-store customers - engaging directly with the business sales staff (or representative), or-(2) its on-line, virtual customers - engaging with the business via internet or remote access. In this situation, both the business, and the customer draw upon their respective viewpoints, and both sides influence the interaction. External to these business and customer influences are additional factors that capture the immediate and broader global effects - termed environmental effects. These three business-customer engagement areas of influence are captured by a SVN SEM approach. Without a business-customer encounter of some kind the likelihood of a services business, and a prospecting customer, successfully engaging in an exchange process is reduced. This exchange may be a physical, and/or services exchange, and/or an information and/or ideas exchange. To the business, this encounter is, in effect, a trade, and as a result, the business targets acquiring an economic exchange that will ultimately deliver a net positive economic outcome. To the customer, external and internal information feeds, servicing, perceived value, and satisfaction, are key encounter drivers. SVNs offers a new way to understand the business-customer encounter, and to then utilize this acquired knowledge to either: (1) build a strategic management model, or (2) reengineer its business networks, and to then create a re-positioned, more customer-aligned business operation - one that is capable of delivering win - win, competitive business-customer solutions.展开更多
This paper firstly examines the value of optical bypass scheme in packet ring networks. An Integer Linear Program (ILP) formulation is presented and analytical results under different traffic patterns are given.
Zhang et al. exploited data on Facebook and Tencent to validate Metcalfe's law, which states that the aggregate value of a communications network is proportional to the square of the number of users. This note points...Zhang et al. exploited data on Facebook and Tencent to validate Metcalfe's law, which states that the aggregate value of a communications network is proportional to the square of the number of users. This note points out that the value of a social network may be driven not only by its size, but also by increases in the variety and quality of the services offered. I therefore extend Zhang et al.'s approach by explicitly controlling for changes in network quality over time. For the case of Tencent, I also filter out revenues and costs that are unrelated to Tencent's core (social network) services. I find that these two extensions only strengthen Zhang et al.'s conclusions: Metcalfe's law now outperforms the other laws even more clearlv.展开更多
This' paper decomposes economic benefits (value-added) and environmental costs (CO2) of exports according to their sources, and maps the global value network (GVN) and the global emissions network (GEN) for C...This' paper decomposes economic benefits (value-added) and environmental costs (CO2) of exports according to their sources, and maps the global value network (GVN) and the global emissions network (GEN) for China's exports during 1995-2009 from national, sectoral and national sectoral perspectives. A comparison is conducted between China and the USA. National GVN and GEN show that shares of value-added and CO2 emissions from China in its GVN and GEN both decreased first then increased after 2006, while shares from the USA in its GVN and GEN generally decreased. Seetoral GVN and GEN show that among China's exports, "electrical and optical equipment" and "electricity, gas and water supply" were, respectively, the sectors that obtained the most value-added and emitted the most CO2. National-sectoral G VN and GEN for China exhibited reciprocal and disassortative patterns, and in-strengths and out-strengths of GVN and GEN for China 's exports were mainly captured by several domestic country-sector pairs.展开更多
Reservoir-induced earthquakes related with the construction of the Three Gorges Project have attracted great concerns of the public. Since the first water impoundment on May 25, 2003, a number of earthquakes have occu...Reservoir-induced earthquakes related with the construction of the Three Gorges Project have attracted great concerns of the public. Since the first water impoundment on May 25, 2003, a number of earthquakes have occurred during the water storage stages, in which the largest was the Badong M5.1 earthquake on December 16, 2013. In this paper, the relationships between seismic activities, b value, seismic parameters, and reservoir water level fluctuations are studied. In addition, based on the digital seismic waveform data obtained since 2000, the focal depth changes and focal mechanism characteristics before and after the water impoundment are studied as well. These provide us important information to understand the earthquake mechanisms. The results show that these earthquakes are typical reservoir-induced earthquakes, which are closely related to water infiltration, pore pressure, and water level fluctuations.The majority of the micro and small earthquakes are caused by karst collapse, mine collapse, bank reformation, superficial unloading, and so on. The larger earthquakes are related to the fault structures to some extent. Due to the persistent effects of water impoundment on the seismic and geological environments around the reservoir and water infiltration into the rocks, the influences on the crustal deformation field, gravity field, seepage field, and fault medium-softening action may vary gradually from a higher strength to a weaker one. Therefore, it is possible that small earthquakes and few medium earthquakes(M≤5.5) will occur in the reservoir area in the future.展开更多
This paper develops an analytical framework to explain the lnternet interconnection settlement issues. The paper shows that multiple linear regression can be used in assessing the network value of lnternet Backbone Pr...This paper develops an analytical framework to explain the lnternet interconnection settlement issues. The paper shows that multiple linear regression can be used in assessing the network value of lnternet Backbone Providers ( IBPs). By using the exchange rate of each network, we can define a rate of network value, which reflects the contribution of each network to interconnection and the interconnected network resource usage by each of the network.展开更多
文摘Intake system of diesel engine is a strong nonlinear system, and it is difficult to establish accurate model of intake system; and bias fault and precision degradation fault of MAP of diesel engine can't be diagnosed easily using model-based methods. Thus, a fault diagnosis method based on Elman neural network observer is proposed. By comparing simulation results of intake pressure based on BP network and Elman neural network, lower sampling error magnitude is gained using Elman neural network, and the error is less volatile. Forecast accuracy is between 0.015?0.017 5 and sample error is controlled within 0?0.07. Considering the output stability and complexity of solving comprehensively, Elman neural network with a single hidden layer and with 44 nodes is presented as intake system observer. By comparing the relations of confidence intervals of the residual value between the measured and predicted values, error variance and failures in various fault types. Then four typical MAP faults of diesel engine can be diagnosed: complete failure fault, bias fault, precision degradation fault and drift fault. The simulation results show: intake pressure is observable and selection of diagnostic strategy parameter reasonably can increase the accuracy of diagnosis;the proposed fault diagnosis method only depends on data and structural parameters of observer, not depends on the nonlinear model of air intake system. A fault diagnosis method is proposed not depending system model to observe intake pressure, and bias fault and precision degradation fault of MAP of diesel engine can be diagnosed based on residuals.
基金support from National Natural Science Foundation of China(Grant No.71971006)Humanities and Social Science Foundation of Ministry of Education of the People’s Republic of China(Grant No.19YJCGJW014).
文摘Purpose:With the availability and utilization of Inter-Country Input-Output(ICIO)tables,it is possible to construct quantitative indices to assess its impact on the Global Value Chain(GVC).For the sake of visualization,ICIO networks with tremendous low-weight edges are too dense to show the substantial structure.These redundant edges,inevitably make the network data full of noise and eventually exert negative effects on Social Network Analysis(SNA).In this case,we need a method to filter such edges and obtain a sparser network with only the meaningful connections.Design/methodology/approach:In this paper,we propose two parameterless pruning algorithms from the global and local perspectives respectively,then the performance of them is examined using the ICIO table from different databases.Findings:The Searching Paths(SP)method extracts the strongest association paths from the global perspective,while Filtering Edges(FE)method captures the key links according to the local weight ratio.The results show that the FE method can basically include the SP method and become the best solution for the ICIO networks.Research limitations:There are still two limitations in this research.One is that the computational complexity may increase rapidly while processing the large-scale networks,so the proposed method should be further improved.The other is that much more empirical networks should be introduced to testify the scientificity and practicability of our methodology.Practical implications:The network pruning methods we proposed will promote the analysis of the ICIO network,in terms of community detection,link prediction,and spatial econometrics,etc.Also,they can be applied to many other complex networks with similar characteristics.Originality/value:This paper improves the existing research from two aspects,namely,considering the heterogeneity of weights and avoiding the interference of parameters.Therefore,it provides a new idea for the research of network backbone extraction.
文摘Under the background of constructing harmonious economic society, how to realize the coordinated development of regions in the course of region integration is a key problem. According to the relevant theory of enterprise gene reconfiguration and enterprise value network construction, we analyzed the problems in the merging course between the value network construction and region economic growth. Finally, we put forward the basic path of coordinated development of regions.
文摘Services may be investigated from many perspectives. They encapsulate over 65% of global business, yet many gaps in the services knowledge base exist – particularly from areas including information technology, operational, customer targeting, and services provision. This research investigates an emerging and truly disruptive business scenario – the service value network, from a marketing, an operations and services approach. The service value network is defined as the flexible, dynamic, delivery of a service, or product, by a business’s coordinated value chains (supply chains and demand chains working in harmony), such that a value-adding, specific, service solution is effectively, and efficiently, delivered to the individual customer. The ‘physical and virtual service value network customer – business encounter model’ is developed. Impediments to the development of a service value networks are investigated. Eight key areas related to website customer encounters are offered as investigation areas. The customer ‘touch-points’ across the virtual service encounter offers a raft of new research possibilities and possible new pathways to competitive advantage. Approaches to measure service network encounter effectors are explained. Current and future areas of business research are described. This paper frames the research agenda for service value networks.
基金Project supported by the National Natural Science Foundation of China(No.61501399)the SAIC MOTOR(No.1925)the National Key R&D Program of China(No.2018AAA0102302)。
文摘In an unmanned aerial vehicle ad-hoc network(UANET),sparse and rapidly mobile unmanned aerial vehicles(UAVs)/nodes can dynamically change the UANET topology.This may lead to UANET service performance issues.In this study,for planning rapidly changing UAV swarms,we propose a dynamic value iteration network(DVIN)model trained using the episodic Q-learning method with the connection information of UANETs to generate a state value spread function,which enables UAVs/nodes to adapt to novel physical locations.We then evaluate the performance of the DVIN model and compare it with the non-dominated sorting genetic algorithm II and the exhaustive method.Simulation results demonstrate that the proposed model significantly reduces the decisionmaking time for UAV/node path planning with a high average success rate.
文摘Modeling a business to match its customer perceived (and customer desired) outcomes, remains an on-going task. This paper considers shows how a service value networks (SVNs) approach may be engaged to model, and deliver, understanding of the front-end business and its direct engagement with its immediate (or front-end) customers. These front-end customers may be either: (1) its off-line, in-store customers - engaging directly with the business sales staff (or representative), or-(2) its on-line, virtual customers - engaging with the business via internet or remote access. In this situation, both the business, and the customer draw upon their respective viewpoints, and both sides influence the interaction. External to these business and customer influences are additional factors that capture the immediate and broader global effects - termed environmental effects. These three business-customer engagement areas of influence are captured by a SVN SEM approach. Without a business-customer encounter of some kind the likelihood of a services business, and a prospecting customer, successfully engaging in an exchange process is reduced. This exchange may be a physical, and/or services exchange, and/or an information and/or ideas exchange. To the business, this encounter is, in effect, a trade, and as a result, the business targets acquiring an economic exchange that will ultimately deliver a net positive economic outcome. To the customer, external and internal information feeds, servicing, perceived value, and satisfaction, are key encounter drivers. SVNs offers a new way to understand the business-customer encounter, and to then utilize this acquired knowledge to either: (1) build a strategic management model, or (2) reengineer its business networks, and to then create a re-positioned, more customer-aligned business operation - one that is capable of delivering win - win, competitive business-customer solutions.
基金This work is supported by National High Project Fund(863) with a project number 2001AA121073.
文摘This paper firstly examines the value of optical bypass scheme in packet ring networks. An Integer Linear Program (ILP) formulation is presented and analytical results under different traffic patterns are given.
文摘Zhang et al. exploited data on Facebook and Tencent to validate Metcalfe's law, which states that the aggregate value of a communications network is proportional to the square of the number of users. This note points out that the value of a social network may be driven not only by its size, but also by increases in the variety and quality of the services offered. I therefore extend Zhang et al.'s approach by explicitly controlling for changes in network quality over time. For the case of Tencent, I also filter out revenues and costs that are unrelated to Tencent's core (social network) services. I find that these two extensions only strengthen Zhang et al.'s conclusions: Metcalfe's law now outperforms the other laws even more clearlv.
基金This study was financially supported by the Beijing Social Science Foundation (No. 17JDYJB010) and the Special Fund for Joint Development Program of Beijing Municipal Commission of Education.
文摘This' paper decomposes economic benefits (value-added) and environmental costs (CO2) of exports according to their sources, and maps the global value network (GVN) and the global emissions network (GEN) for China's exports during 1995-2009 from national, sectoral and national sectoral perspectives. A comparison is conducted between China and the USA. National GVN and GEN show that shares of value-added and CO2 emissions from China in its GVN and GEN both decreased first then increased after 2006, while shares from the USA in its GVN and GEN generally decreased. Seetoral GVN and GEN show that among China's exports, "electrical and optical equipment" and "electricity, gas and water supply" were, respectively, the sectors that obtained the most value-added and emitted the most CO2. National-sectoral G VN and GEN for China exhibited reciprocal and disassortative patterns, and in-strengths and out-strengths of GVN and GEN for China 's exports were mainly captured by several domestic country-sector pairs.
基金supported by the National Natural Science Foundation of China (41572354)the Key Foundation of the Institute of Seismology (IS201616254)
文摘Reservoir-induced earthquakes related with the construction of the Three Gorges Project have attracted great concerns of the public. Since the first water impoundment on May 25, 2003, a number of earthquakes have occurred during the water storage stages, in which the largest was the Badong M5.1 earthquake on December 16, 2013. In this paper, the relationships between seismic activities, b value, seismic parameters, and reservoir water level fluctuations are studied. In addition, based on the digital seismic waveform data obtained since 2000, the focal depth changes and focal mechanism characteristics before and after the water impoundment are studied as well. These provide us important information to understand the earthquake mechanisms. The results show that these earthquakes are typical reservoir-induced earthquakes, which are closely related to water infiltration, pore pressure, and water level fluctuations.The majority of the micro and small earthquakes are caused by karst collapse, mine collapse, bank reformation, superficial unloading, and so on. The larger earthquakes are related to the fault structures to some extent. Due to the persistent effects of water impoundment on the seismic and geological environments around the reservoir and water infiltration into the rocks, the influences on the crustal deformation field, gravity field, seepage field, and fault medium-softening action may vary gradually from a higher strength to a weaker one. Therefore, it is possible that small earthquakes and few medium earthquakes(M≤5.5) will occur in the reservoir area in the future.
文摘This paper develops an analytical framework to explain the lnternet interconnection settlement issues. The paper shows that multiple linear regression can be used in assessing the network value of lnternet Backbone Providers ( IBPs). By using the exchange rate of each network, we can define a rate of network value, which reflects the contribution of each network to interconnection and the interconnected network resource usage by each of the network.