Response surface methodology（RSM） is introduced into corrosion research as a tool to assess the effects of environmental factors and their interactions on corrosion behavior and establish a model for corrosion predi...Response surface methodology（RSM） is introduced into corrosion research as a tool to assess the effects of environmental factors and their interactions on corrosion behavior and establish a model for corrosion prediction in complex coupled environment（CCE）. In this study, a typical CCE, that is, the corrosion environment of pipelines in gas field is taken as an example. The effects of environmental factors such as chloride concentration, pH value and pressure as well as their interactions on critical pitting temperature（CPT） were evaluated, and a quadratic polynomial model was developed for corrosion prediction by RSM. The results showed that the model was excellent in corrosion prediction with R2= 0.9949. CPT was mostly affected by single environmental factor rather than interaction, and among the whole factors, chloride concentration was the most influential factor of CPT.展开更多
Urban transportation systems are facing severe challenges due to the rapid growth of the urban population,especially in China.Suspended monorail system(SMS),as a sky rail transportation form,can effectively alleviate ...Urban transportation systems are facing severe challenges due to the rapid growth of the urban population,especially in China.Suspended monorail system(SMS),as a sky rail transportation form,can effectively alleviate urban traffic congestion due to its independent right-of-way and minimal ground footprint.However,the SMS possesses a special traveling system with unique vehicle structure and bridge configuration,which results in significant differences in both the mechanisms and dynamics problems associated with train–bridge interaction(TBI)when contrasted with those of traditional railway systems.Therefore,a thorough understanding of the SMS dynamics is essential for ensuring the operational safety of the system.This article presents a state-of-the-art review of the TBI modeling methodologies,critical dynamic features,field tests,and practice of the SMS in China.Firstly,the development history,technical features,and potential dynamics problems of the SMS are briefly described,followed by the mechanical characteristics and mechanisms of the train–bridge interactive systems.Then,the modeling methodology of the fundamental elements in the suspended monorail TBI is systematically reviewed,including the suspended train subsystem,bridge subsystem,train–bridge interaction relationships,system excitations,and solution method.Further,the typical dynamic features of the TBI under various operational scenarios are elaborated,including different train speeds,a variety of line sections,and a natural wind environment.Finally,the first new energy-based SMS test line in the world is systematically introduced,including the composition and functionality of the system,the details of the conducted field tests,and the measured results of the typical dynamic responses.At the end of the paper,both the guidance on further improvement of the SMS and future research topics are proposed.展开更多
Significant advances in regional groundwater flow modeling have been driven by the demand to predict regional impacts of human inferences on groundwater systems and associated environment. The wide availability of pow...Significant advances in regional groundwater flow modeling have been driven by the demand to predict regional impacts of human inferences on groundwater systems and associated environment. The wide availability of powerful computers, user friendly modeling systems and GIS stimulates an exponential growth of regional groundwater modeling. Large scale transient groundwater models have been built to analyze regional flow systems, to simulate water budget components changes, and to optimize groundwater develop- ment scenarios. This paper reviews the historical development of regional groundwater modeling. Examples of Death Valley and Great Artesian Basin transient groundwater models are introduced to show the application of large scale regional groundwater flow models. Specific methodologies for regional groundwater flow modeling are descried and special issues in regional groundwater flow modeling are discussed.展开更多
Openness is one of the features of modern robot controllers. Although many modeling technologies have been discussed to model and develop open robot controllers, the focus is always on modeling methodology. The relati...Openness is one of the features of modern robot controllers. Although many modeling technologies have been discussed to model and develop open robot controllers, the focus is always on modeling methodology. The relation between the former and the latter is usually ignored. According to the general software architecture of open robot controllers, this paper discusses modeling and developing methods. And the relation between the typical ones is analyzed.展开更多
The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into...The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities.展开更多
Frequency and voltage dynamics,as the focus of power systems,depend more and more on the frequency and amplitude response characteristics of renewable energy devices subjected to power imbalance.The doubly-fed inducti...Frequency and voltage dynamics,as the focus of power systems,depend more and more on the frequency and amplitude response characteristics of renewable energy devices subjected to power imbalance.The doubly-fed induction generator(DFIG)-based wind turbine(WT)is representative of renewable energy devices and shows different characteristics from those of conventional synchronous generators(SGs).Unfortunately,the individual characteristics of WTs during system frequency and voltage dynamics are not intuitively illustrated by the existing structure-oriented models.Therefore,this paper proposes a function-oriented modeling methodology by representing inertia-controlled DFIG-based WT as an internal voltage frequency and amplitude solely stimulated by active and reactive power imbalance.The individuality of the characteristics is demonstrated by the grid voltage detection-based controls that the internal voltage depends solely on the power imbalance of WTs,just like the case of SGs.Through the infinity gain equivalence of the fast-electromagnetic loops,a simplified analytical model illustrating the electromechanical characteristics of WTs is further proposed.Based on the model,the similarities and differences between the characteristics of WTs and SGs are recognized.Simulation results are also presented for verification.展开更多
In the circumstances of the 21st-century digital and technological turn,and due to the burst of the cosmopolitan way of living,the urban environment has gradually transformed in its appearance and identity.The loss of...In the circumstances of the 21st-century digital and technological turn,and due to the burst of the cosmopolitan way of living,the urban environment has gradually transformed in its appearance and identity.The loss of object singularity in urban context due to continuous variability and functional indeterminacy blurs the boundaries between architectural and urban scale,personal and social experience.Through an interdisciplinary framework,this paper deals with the fluidity phenomenon instrumentalisation through value-based research of renominated architectural practices in creating an authentic methodological research model that connects urban dynamics and architectural design methods,techniques and instruments in shaping a contemporary spatial experience.The resulting methodological model employs an analytic graphic narrative to formulate a strategy integrating fluidity into the process of architectural design.The paper explains how architectural design,as a cultural practice,employs fluidity to incorporate dynamics and needs,strategically enhancing the expression of urban values,requirements,and narratives.展开更多
Research on the last 30 years of architectural heritage conservation in Shanghai would highlight the establishment of both a preliminary system for heritage classification and gradation,as well as an authorised herita...Research on the last 30 years of architectural heritage conservation in Shanghai would highlight the establishment of both a preliminary system for heritage classification and gradation,as well as an authorised heritage institution framework.During the course of this process,different conservation methodologies and models(restorations,additions,relocations,extensions and reconstructions)have been put into practice according to the actual situation of the historic architecture of Shanghai.An overall view shows how architectural heritage conservation in Shanghai has undergone three different phases-initial;experimental;and the deepening conservation phase,on which a fundamental step was given in 2002,when the Shanghai Municipal Government issued the‘Legislation for the Conservation of Historical Areas and Heritage Architecture in Shanghai’,creating a conservation system that is participated by the authorities,academic institutions,design institutions and construction companies.The article also stresses the need to provide for a special system of architectural heritage conservation in Shanghai,acknowledging the specificity of its cultural heritage,administrative system,legislation,codes,building technologies and materials;as well as its particular historical situation.展开更多
基金financially supported by the Hundred Talents Program of Chinese Academy of Sciencesthe National Natural Science Foundation of China (No. U1460202)the Key Laboratory of Superlight Material and Surface Technology (Harbin Engineering University), Ministry of Education
文摘Response surface methodology（RSM） is introduced into corrosion research as a tool to assess the effects of environmental factors and their interactions on corrosion behavior and establish a model for corrosion prediction in complex coupled environment（CCE）. In this study, a typical CCE, that is, the corrosion environment of pipelines in gas field is taken as an example. The effects of environmental factors such as chloride concentration, pH value and pressure as well as their interactions on critical pitting temperature（CPT） were evaluated, and a quadratic polynomial model was developed for corrosion prediction by RSM. The results showed that the model was excellent in corrosion prediction with R2= 0.9949. CPT was mostly affected by single environmental factor rather than interaction, and among the whole factors, chloride concentration was the most influential factor of CPT.
基金supported by the National Natural Science Foundation of China(Grant Nos.52202483,52108476,and 52388102)。
文摘Urban transportation systems are facing severe challenges due to the rapid growth of the urban population,especially in China.Suspended monorail system(SMS),as a sky rail transportation form,can effectively alleviate urban traffic congestion due to its independent right-of-way and minimal ground footprint.However,the SMS possesses a special traveling system with unique vehicle structure and bridge configuration,which results in significant differences in both the mechanisms and dynamics problems associated with train–bridge interaction(TBI)when contrasted with those of traditional railway systems.Therefore,a thorough understanding of the SMS dynamics is essential for ensuring the operational safety of the system.This article presents a state-of-the-art review of the TBI modeling methodologies,critical dynamic features,field tests,and practice of the SMS in China.Firstly,the development history,technical features,and potential dynamics problems of the SMS are briefly described,followed by the mechanical characteristics and mechanisms of the train–bridge interactive systems.Then,the modeling methodology of the fundamental elements in the suspended monorail TBI is systematically reviewed,including the suspended train subsystem,bridge subsystem,train–bridge interaction relationships,system excitations,and solution method.Further,the typical dynamic features of the TBI under various operational scenarios are elaborated,including different train speeds,a variety of line sections,and a natural wind environment.Finally,the first new energy-based SMS test line in the world is systematically introduced,including the composition and functionality of the system,the details of the conducted field tests,and the measured results of the typical dynamic responses.At the end of the paper,both the guidance on further improvement of the SMS and future research topics are proposed.
文摘Significant advances in regional groundwater flow modeling have been driven by the demand to predict regional impacts of human inferences on groundwater systems and associated environment. The wide availability of powerful computers, user friendly modeling systems and GIS stimulates an exponential growth of regional groundwater modeling. Large scale transient groundwater models have been built to analyze regional flow systems, to simulate water budget components changes, and to optimize groundwater develop- ment scenarios. This paper reviews the historical development of regional groundwater modeling. Examples of Death Valley and Great Artesian Basin transient groundwater models are introduced to show the application of large scale regional groundwater flow models. Specific methodologies for regional groundwater flow modeling are descried and special issues in regional groundwater flow modeling are discussed.
文摘Openness is one of the features of modern robot controllers. Although many modeling technologies have been discussed to model and develop open robot controllers, the focus is always on modeling methodology. The relation between the former and the latter is usually ignored. According to the general software architecture of open robot controllers, this paper discusses modeling and developing methods. And the relation between the typical ones is analyzed.
基金Study on the Path of Promoting the Integration of“Three Societies”and Help Rural Revitalization in Chongqing,Chongqing Social Science Planning Office[Grant number.2019WT13]Study on the Cultivation of Language Service Talents Under the Background of Belt and Road Initiative,Chongqing Social Science Planning Office[Grant number.2021WYZX12].
文摘The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities.
基金supported by the Joint Fund of the National Natural Science Foundation of China(No.U1866601).
文摘Frequency and voltage dynamics,as the focus of power systems,depend more and more on the frequency and amplitude response characteristics of renewable energy devices subjected to power imbalance.The doubly-fed induction generator(DFIG)-based wind turbine(WT)is representative of renewable energy devices and shows different characteristics from those of conventional synchronous generators(SGs).Unfortunately,the individual characteristics of WTs during system frequency and voltage dynamics are not intuitively illustrated by the existing structure-oriented models.Therefore,this paper proposes a function-oriented modeling methodology by representing inertia-controlled DFIG-based WT as an internal voltage frequency and amplitude solely stimulated by active and reactive power imbalance.The individuality of the characteristics is demonstrated by the grid voltage detection-based controls that the internal voltage depends solely on the power imbalance of WTs,just like the case of SGs.Through the infinity gain equivalence of the fast-electromagnetic loops,a simplified analytical model illustrating the electromechanical characteristics of WTs is further proposed.Based on the model,the similarities and differences between the characteristics of WTs and SGs are recognized.Simulation results are also presented for verification.
文摘In the circumstances of the 21st-century digital and technological turn,and due to the burst of the cosmopolitan way of living,the urban environment has gradually transformed in its appearance and identity.The loss of object singularity in urban context due to continuous variability and functional indeterminacy blurs the boundaries between architectural and urban scale,personal and social experience.Through an interdisciplinary framework,this paper deals with the fluidity phenomenon instrumentalisation through value-based research of renominated architectural practices in creating an authentic methodological research model that connects urban dynamics and architectural design methods,techniques and instruments in shaping a contemporary spatial experience.The resulting methodological model employs an analytic graphic narrative to formulate a strategy integrating fluidity into the process of architectural design.The paper explains how architectural design,as a cultural practice,employs fluidity to incorporate dynamics and needs,strategically enhancing the expression of urban values,requirements,and narratives.
文摘Research on the last 30 years of architectural heritage conservation in Shanghai would highlight the establishment of both a preliminary system for heritage classification and gradation,as well as an authorised heritage institution framework.During the course of this process,different conservation methodologies and models(restorations,additions,relocations,extensions and reconstructions)have been put into practice according to the actual situation of the historic architecture of Shanghai.An overall view shows how architectural heritage conservation in Shanghai has undergone three different phases-initial;experimental;and the deepening conservation phase,on which a fundamental step was given in 2002,when the Shanghai Municipal Government issued the‘Legislation for the Conservation of Historical Areas and Heritage Architecture in Shanghai’,creating a conservation system that is participated by the authorities,academic institutions,design institutions and construction companies.The article also stresses the need to provide for a special system of architectural heritage conservation in Shanghai,acknowledging the specificity of its cultural heritage,administrative system,legislation,codes,building technologies and materials;as well as its particular historical situation.
