Although lithium-ion batteries(LIBs)currently dominate a wide spectrum of energy storage applications,they face challenges such as fast cycle life decay and poor stability that hinder their further application.To addr...Although lithium-ion batteries(LIBs)currently dominate a wide spectrum of energy storage applications,they face challenges such as fast cycle life decay and poor stability that hinder their further application.To address these limitations,element doping has emerged as a prevalent strategy to enhance the discharge capacity and extend the durability of Li-Ni-Co-Mn(LNCM)ternary compounds.This study utilized a machine learning-driven feature screening method to effectively pinpoint four key features crucially impacting the initial discharge capacity(IC)of Li-Ni-Co-Mn(LNCM)ternary cathode materials.These features were also proved highly predictive for the 50^(th)cycle discharge capacity(EC).Additionally,the application of SHAP value analysis yielded an in-depth understanding of the interplay between these features and discharge performance.This insight offers valuable direction for future advancements in the development of LNCM cathode materials,effectively promoting this field toward greater efficiency and sustainability.展开更多
Plain concrete is strong in compression but brittle in tension,having a low tensile strain capacity that can significantly degrade the long-term performance of concrete structures,even when steel reinforcing is presen...Plain concrete is strong in compression but brittle in tension,having a low tensile strain capacity that can significantly degrade the long-term performance of concrete structures,even when steel reinforcing is present.In order to address these challenges,short polymer fibers are randomly dispersed in a cement-based matrix to forma highly ductile engineered cementitious composite(ECC).Thismaterial exhibits high ductility under tensile forces,with its tensile strain being several hundred times greater than conventional concrete.Since concrete is inherently weak in tension,the tensile strain capacity(TSC)has become one of the most extensively researched properties.As a result,developing a model to predict the TSC of the ECC and to optimize the mixture proportions becomes challenging.Meanwhile,the effort required for laboratory trial batches to determine the TSC is reduced.To achieve the research objectives,five distinct models,artificial neural network(ANN),nonlinear model(NLR),linear relationship model(LR),multi-logistic model(MLR),and M5P-tree model(M5P),are investigated and employed to predict the TSCof ECCmixtures containing fly ash.Data from115 mixtures are gathered and analyzed to develop a new model.The input variables include mixture proportions,fiber length and diameter,and the time required for curing the various mixtures.The model’s effectiveness is evaluated and verified based on statistical parameters such as R2,mean absolute error(MAE),scatter index(SI),root mean squared error(RMSE),and objective function(OBJ)value.Consequently,the ANN model outperforms the others in predicting the TSC of the ECC,with RMSE,MAE,OBJ,SI,and R2 values of 0.42%,0.3%,0.33%,0.135%,and 0.98,respectively.展开更多
Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(LIBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,lo...Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(LIBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,low ionic diffusion and large volume expansion during Li/Na-ion intercalation significantly impairing the Li/Na-storage performance.Herein,a long chain heterostructure composed of the Co_(9)S_(8) and SnS are first reported,which can generate rich phase interfaces,and small crystal domains.The unique structure can facilitate the properties of reactivity,conductivity and ionic diffusion.In addition,the heterostructure surface is modified by the N-doped carbon(N-DC@(CoSn)S),successfully improving the structural stability.The synergistic effects of Co_(9)S_(8)/SnS heterostructure and coated carbon layer effectively increase the capacity and cycling stability.The N-DC@(CoSn)S anode delivers enhanced high specific capacities of 820.6 mAh·g^(−1) at 1.0 A·g^(–1) after 500 cycles for LIBs and 339.2 mAh·g^(–1)at 0.5 A·g^(–1) after 1000 cycles for SIBs,respectively.This work is expected to provide a material design idea for preparing LIBs/SIBs with high capacity and long cycling life.展开更多
Refugee settlements face several challenges in transitioning from a temporary planning approach to more sustainable settlements. This is mainly due to an increase in the number of forcibly displaced people over the la...Refugee settlements face several challenges in transitioning from a temporary planning approach to more sustainable settlements. This is mainly due to an increase in the number of forcibly displaced people over the last few decades, and the difficulties of sustainably providing social services that meet the required standards. The development of refugee settlements assumed that forcibly displaced people would return to their places or countries of origin. Unfortunately, displacement situations are prolonged indefinitely, forcing these people to spend most of their lives in conditions that are often deplorable and substandard, and therefore unsustainable. In most cases, the establishment of refugee settlements is triggered by an emergency caused by an influx of forcibly displaced people, who need to be accommodated urgently and provided with some form of international assistance and protection. This leaves little or no time for proper planning for long-term development as required. In addition, the current approach to temporary settlement harms the environment and can strain limited resources with ad hoc development models that have exacerbated difficulties. As a result, living conditions in refugee settlements have deteriorated over the last few decades and continue to pose challenges as to how best to design, plan, and sustain settlements over time. To contribute to addressing these challenges, this study proposes a new methodology supported by Model-Based Systems Engineering (MBSE) and a Systems Modeling Language (SysML) to develop a typical sustainable human settlement system model, which has functionally and operationally executed using a Systems Engineering (SE) approach. To assess the sustainability capacity of the proposed system, this work applies a matrix of crossed impact multiplication through a case study by conducting a system capacity interdependence analysis (SCIA) using the MICMAC methodology (Cross-impact matrix multiplication applied to classification) to assess the interdependency that exist between the sub-systems categories to deliver services at the system level. The sustainability analysis results based on capacity variables influence and dependency models shows that development activities in the settlement are unstable and, therefore, unsustainable since there is no apparent difference between the influential and dependent data used for the assessment. These results illustrate that an integrated system could improve human settlements’ sustainability and that capacity building in service delivery is beneficial and necessary.展开更多
In order to realize the in-situ evaluation of reinforced concrete bridges subjected to fatigue for a long time or after earthquake, an evaluation method for cumulative damage of concrete structures based on unloading ...In order to realize the in-situ evaluation of reinforced concrete bridges subjected to fatigue for a long time or after earthquake, an evaluation method for cumulative damage of concrete structures based on unloading elastic modulus was proposed. First, according to the concrete stress-strain curve and the statistical relationship between residual strain and cumulative strain, the calculation method of static equivalent strain and residual strain concrete based on unloading elastic modulus and the method for estimating the strength of concrete after damage were proposed. The detailed steps of field test and analysis and the practical damage indicators of residual strain were given. Then, the evaluation method of existing stress and strain of Reinforced Concrete Bridge under dead load and the concept of “equivalent dead load bending moment” were put forward. On this basis, the paper analyzed the root cause of the decrease of bearing capacity of Reinforced Concrete Bridge after fatigue damage, and pointed out that the equivalent strain or residual strain of reinforced concrete increases under the fatigue effect, which led to the decreasing of actual live moment and deformation performance while the ultimate load-carrying capacity remained constant or very little decrease. The evaluation method of structure residual capacity was given, and through comparative analysis of eight T reinforced concrete beams that had been in service for 35 years with the static failure tests, the effectiveness of the method was verified.展开更多
This article uses real engineering projects as examples to analyze how static load test technology is applied in testing the bridge-bearing capacity.The analysis covers aspects such as testing section layout,test load...This article uses real engineering projects as examples to analyze how static load test technology is applied in testing the bridge-bearing capacity.The analysis covers aspects such as testing section layout,test load and efficiency coefficient,loading plan,evaluation optimization,test result modification,and result evaluation.The aim is to support the accurate detection and evaluation of bridge-bearing capacity.展开更多
A bridge project is taken as an example to analyze the application of bearing capacity detection and evaluation.This article provides a basic overview of the project,the application of bearing capacity detection techn...A bridge project is taken as an example to analyze the application of bearing capacity detection and evaluation.This article provides a basic overview of the project,the application of bearing capacity detection technology,and the bearing capacity assessment analysis.It is hoped that this analysis can provide a scientific reference for the load-bearing capacity detection and evaluation work in bridge engineering projects,thereby achieving a scientific assessment of the overall load-bearing capacity of the bridge engineering structure.展开更多
In recent years, the subcontracting production for foreign trade of the Xi’an Aviation Engine Company (XAEC), a foreign trade production base of China, has achieved rapid development. In 1994, the company’s export e...In recent years, the subcontracting production for foreign trade of the Xi’an Aviation Engine Company (XAEC), a foreign trade production base of China, has achieved rapid development. In 1994, the company’s export earnings from foreign trade made a breakthrough at US$11 million, and it was commended by the State Economic展开更多
The degradation strength of soils under cyclic loading is studied and a method for determining the cyclic degradation strength with cyclic triaxial tests is given in the paper. Furthermore, a dum my static method for ...The degradation strength of soils under cyclic loading is studied and a method for determining the cyclic degradation strength with cyclic triaxial tests is given in the paper. Furthermore, a dum my static method for estimating the undrained bearing capacity for offshore soft foundation under wave loads is developed. It can consider the effect of the difference of cyclic stress for different parts of the foundation on both the degradation strength of the foundation soil and the bearing capacity so that the estimated result can better reflect the real condition of foundation under cyclic loading. The method can be applied to plane and space problem.展开更多
Combined with the actual situation of the western region city of Zunyi, the three subsystems including social, economic and natural environment evaluation index systems of ECC have been built based on the theory of ec...Combined with the actual situation of the western region city of Zunyi, the three subsystems including social, economic and natural environment evaluation index systems of ECC have been built based on the theory of ecological carrying capacity(ECC). In addition, the factor analysis method has been used and the influence factors on the ECC in the economic transition have been gained. The results show that factors of ECC in the three subsystems have different influence: 1) the natural subsystem, which contains factors on the ECC, has obvious limitation, and it has the greatest influence on industrial waste discharge per capita; 2) the social subsystem has a restriction on the ECC, which affects the traffic environment mostly; 3) the economic subsystem has a certain restriction on ECC, which has a large effect on the consumption level per capita.展开更多
There are two different genetic types of recently deposited silts widely distributing in Huaibei Plain of Anhui Province:flooding deposited silt of Yellow River and Huaihe River.These recently deposited silts have the...There are two different genetic types of recently deposited silts widely distributing in Huaibei Plain of Anhui Province:flooding deposited silt of Yellow River and Huaihe River.These recently deposited silts have the following unique characteristics:new formation age,feeble consolidation degree。展开更多
基于基波磁通补偿的串联混合型有源电力滤波器（active power filter,APF）应用于高电压、大容量的谐波抑制场合时,受变压器励磁支路谐波电压的影响,逆变器不能等效为基波电流源,其输出电流将含有大量的谐波,从而影响滤波效果。以逆变...基于基波磁通补偿的串联混合型有源电力滤波器（active power filter,APF）应用于高电压、大容量的谐波抑制场合时,受变压器励磁支路谐波电压的影响,逆变器不能等效为基波电流源,其输出电流将含有大量的谐波,从而影响滤波效果。以逆变器为核心,推导出在励磁支路谐波压降影响下的串联变压器的谐波等效阻抗。并以此为基础,从理论上分析励磁电感和变比对串联变压器谐波等效阻抗和APF滤波效果的影响。仿真结果验证了理论分析的正确性。最后,针对广东某厂10kV、1MVA电力负荷,研制一套基于基波磁通补偿的串联混合型有源滤波器工程样机,取得非常好的滤波效果。展开更多
Use of indices that quantify the seismic residual capacity of buildings damaged in earthquakes is one way to draw judgements on the building’s safety and possibility of future use.In Japanese damage assessment guidel...Use of indices that quantify the seismic residual capacity of buildings damaged in earthquakes is one way to draw judgements on the building’s safety and possibility of future use.In Japanese damage assessment guidelines,several approximate calculation methods exist to evaluate the residual capacity of buildings based on visually observed damage and simplifying assumptions on the nature of the building’s response mechanism and member capacities.While these methods provide a useful residual capacity ratio that enables a‘relative’comparison be-tween buildings,the exact relationship to a physically meaningful residual capacity is unclear.The aim of this study is to benchmark the‘approximations’of residual capacity.To do so,a shake-table test was conducted on a 14 scale 4-storey RC structure and a residual capacity evaluation was undertaken based on observed damage states.With the help of a numerical model,a benchmark residual capacity at each of the damage states is determined and compared to the approximate residual capacity calculation results via guidelines.It was found that approx-imate methods are generally accurate prior to yield but can become overly conservative post-yield.Simplifying assumptions of equal member deformation capacity used in the residual capacity ratio calculation was found to be suitable given constraints of rapid field evaluations.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52122408,52071023)the Program for Science&Technology Innovation Talents in the University of Henan Province(No.22HASTIT1006)+2 种基金the Program for Central Plains Talents(No.ZYYCYU202012172)the Ministry of Education,Singapore(No.RG70/20)the Opening Project of National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials,Henan University of Science and Technology(No.HKDNM201906).
文摘Although lithium-ion batteries(LIBs)currently dominate a wide spectrum of energy storage applications,they face challenges such as fast cycle life decay and poor stability that hinder their further application.To address these limitations,element doping has emerged as a prevalent strategy to enhance the discharge capacity and extend the durability of Li-Ni-Co-Mn(LNCM)ternary compounds.This study utilized a machine learning-driven feature screening method to effectively pinpoint four key features crucially impacting the initial discharge capacity(IC)of Li-Ni-Co-Mn(LNCM)ternary cathode materials.These features were also proved highly predictive for the 50^(th)cycle discharge capacity(EC).Additionally,the application of SHAP value analysis yielded an in-depth understanding of the interplay between these features and discharge performance.This insight offers valuable direction for future advancements in the development of LNCM cathode materials,effectively promoting this field toward greater efficiency and sustainability.
文摘Plain concrete is strong in compression but brittle in tension,having a low tensile strain capacity that can significantly degrade the long-term performance of concrete structures,even when steel reinforcing is present.In order to address these challenges,short polymer fibers are randomly dispersed in a cement-based matrix to forma highly ductile engineered cementitious composite(ECC).Thismaterial exhibits high ductility under tensile forces,with its tensile strain being several hundred times greater than conventional concrete.Since concrete is inherently weak in tension,the tensile strain capacity(TSC)has become one of the most extensively researched properties.As a result,developing a model to predict the TSC of the ECC and to optimize the mixture proportions becomes challenging.Meanwhile,the effort required for laboratory trial batches to determine the TSC is reduced.To achieve the research objectives,five distinct models,artificial neural network(ANN),nonlinear model(NLR),linear relationship model(LR),multi-logistic model(MLR),and M5P-tree model(M5P),are investigated and employed to predict the TSCof ECCmixtures containing fly ash.Data from115 mixtures are gathered and analyzed to develop a new model.The input variables include mixture proportions,fiber length and diameter,and the time required for curing the various mixtures.The model’s effectiveness is evaluated and verified based on statistical parameters such as R2,mean absolute error(MAE),scatter index(SI),root mean squared error(RMSE),and objective function(OBJ)value.Consequently,the ANN model outperforms the others in predicting the TSC of the ECC,with RMSE,MAE,OBJ,SI,and R2 values of 0.42%,0.3%,0.33%,0.135%,and 0.98,respectively.
基金This study was financially supported by the National Natural Science Foundation of China(Nos.52271211 and 52171207)the HORIZON-Marie Skłodowska-Curie Actions-2021-PF(No.101065098)+2 种基金Hunan Provincial Natural Science Foundation of China(No.2022JJ40162)the Scientific Research Fund of Hunan Provincial Education Department(No.21B0406)the science and technology innovation Program of Hunan Province(No.2022RC3037).
文摘Transition metal sulfide(TMS)anodes exhibit the characteristics of phase stability and high capacity for lithium/sodium-ion batteries(LIBs/SIBs).However,the TMS anodes often suffer from poor electronic conductivity,low ionic diffusion and large volume expansion during Li/Na-ion intercalation significantly impairing the Li/Na-storage performance.Herein,a long chain heterostructure composed of the Co_(9)S_(8) and SnS are first reported,which can generate rich phase interfaces,and small crystal domains.The unique structure can facilitate the properties of reactivity,conductivity and ionic diffusion.In addition,the heterostructure surface is modified by the N-doped carbon(N-DC@(CoSn)S),successfully improving the structural stability.The synergistic effects of Co_(9)S_(8)/SnS heterostructure and coated carbon layer effectively increase the capacity and cycling stability.The N-DC@(CoSn)S anode delivers enhanced high specific capacities of 820.6 mAh·g^(−1) at 1.0 A·g^(–1) after 500 cycles for LIBs and 339.2 mAh·g^(–1)at 0.5 A·g^(–1) after 1000 cycles for SIBs,respectively.This work is expected to provide a material design idea for preparing LIBs/SIBs with high capacity and long cycling life.
文摘Refugee settlements face several challenges in transitioning from a temporary planning approach to more sustainable settlements. This is mainly due to an increase in the number of forcibly displaced people over the last few decades, and the difficulties of sustainably providing social services that meet the required standards. The development of refugee settlements assumed that forcibly displaced people would return to their places or countries of origin. Unfortunately, displacement situations are prolonged indefinitely, forcing these people to spend most of their lives in conditions that are often deplorable and substandard, and therefore unsustainable. In most cases, the establishment of refugee settlements is triggered by an emergency caused by an influx of forcibly displaced people, who need to be accommodated urgently and provided with some form of international assistance and protection. This leaves little or no time for proper planning for long-term development as required. In addition, the current approach to temporary settlement harms the environment and can strain limited resources with ad hoc development models that have exacerbated difficulties. As a result, living conditions in refugee settlements have deteriorated over the last few decades and continue to pose challenges as to how best to design, plan, and sustain settlements over time. To contribute to addressing these challenges, this study proposes a new methodology supported by Model-Based Systems Engineering (MBSE) and a Systems Modeling Language (SysML) to develop a typical sustainable human settlement system model, which has functionally and operationally executed using a Systems Engineering (SE) approach. To assess the sustainability capacity of the proposed system, this work applies a matrix of crossed impact multiplication through a case study by conducting a system capacity interdependence analysis (SCIA) using the MICMAC methodology (Cross-impact matrix multiplication applied to classification) to assess the interdependency that exist between the sub-systems categories to deliver services at the system level. The sustainability analysis results based on capacity variables influence and dependency models shows that development activities in the settlement are unstable and, therefore, unsustainable since there is no apparent difference between the influential and dependent data used for the assessment. These results illustrate that an integrated system could improve human settlements’ sustainability and that capacity building in service delivery is beneficial and necessary.
文摘In order to realize the in-situ evaluation of reinforced concrete bridges subjected to fatigue for a long time or after earthquake, an evaluation method for cumulative damage of concrete structures based on unloading elastic modulus was proposed. First, according to the concrete stress-strain curve and the statistical relationship between residual strain and cumulative strain, the calculation method of static equivalent strain and residual strain concrete based on unloading elastic modulus and the method for estimating the strength of concrete after damage were proposed. The detailed steps of field test and analysis and the practical damage indicators of residual strain were given. Then, the evaluation method of existing stress and strain of Reinforced Concrete Bridge under dead load and the concept of “equivalent dead load bending moment” were put forward. On this basis, the paper analyzed the root cause of the decrease of bearing capacity of Reinforced Concrete Bridge after fatigue damage, and pointed out that the equivalent strain or residual strain of reinforced concrete increases under the fatigue effect, which led to the decreasing of actual live moment and deformation performance while the ultimate load-carrying capacity remained constant or very little decrease. The evaluation method of structure residual capacity was given, and through comparative analysis of eight T reinforced concrete beams that had been in service for 35 years with the static failure tests, the effectiveness of the method was verified.
文摘This article uses real engineering projects as examples to analyze how static load test technology is applied in testing the bridge-bearing capacity.The analysis covers aspects such as testing section layout,test load and efficiency coefficient,loading plan,evaluation optimization,test result modification,and result evaluation.The aim is to support the accurate detection and evaluation of bridge-bearing capacity.
文摘A bridge project is taken as an example to analyze the application of bearing capacity detection and evaluation.This article provides a basic overview of the project,the application of bearing capacity detection technology,and the bearing capacity assessment analysis.It is hoped that this analysis can provide a scientific reference for the load-bearing capacity detection and evaluation work in bridge engineering projects,thereby achieving a scientific assessment of the overall load-bearing capacity of the bridge engineering structure.
文摘In recent years, the subcontracting production for foreign trade of the Xi’an Aviation Engine Company (XAEC), a foreign trade production base of China, has achieved rapid development. In 1994, the company’s export earnings from foreign trade made a breakthrough at US$11 million, and it was commended by the State Economic
基金This project was financially supported by the National Natural Science Foundation of China(No.59679018)
文摘The degradation strength of soils under cyclic loading is studied and a method for determining the cyclic degradation strength with cyclic triaxial tests is given in the paper. Furthermore, a dum my static method for estimating the undrained bearing capacity for offshore soft foundation under wave loads is developed. It can consider the effect of the difference of cyclic stress for different parts of the foundation on both the degradation strength of the foundation soil and the bearing capacity so that the estimated result can better reflect the real condition of foundation under cyclic loading. The method can be applied to plane and space problem.
文摘Combined with the actual situation of the western region city of Zunyi, the three subsystems including social, economic and natural environment evaluation index systems of ECC have been built based on the theory of ecological carrying capacity(ECC). In addition, the factor analysis method has been used and the influence factors on the ECC in the economic transition have been gained. The results show that factors of ECC in the three subsystems have different influence: 1) the natural subsystem, which contains factors on the ECC, has obvious limitation, and it has the greatest influence on industrial waste discharge per capita; 2) the social subsystem has a restriction on the ECC, which affects the traffic environment mostly; 3) the economic subsystem has a certain restriction on ECC, which has a large effect on the consumption level per capita.
文摘There are two different genetic types of recently deposited silts widely distributing in Huaibei Plain of Anhui Province:flooding deposited silt of Yellow River and Huaihe River.These recently deposited silts have the following unique characteristics:new formation age,feeble consolidation degree。
文摘基于基波磁通补偿的串联混合型有源电力滤波器（active power filter,APF）应用于高电压、大容量的谐波抑制场合时,受变压器励磁支路谐波电压的影响,逆变器不能等效为基波电流源,其输出电流将含有大量的谐波,从而影响滤波效果。以逆变器为核心,推导出在励磁支路谐波压降影响下的串联变压器的谐波等效阻抗。并以此为基础,从理论上分析励磁电感和变比对串联变压器谐波等效阻抗和APF滤波效果的影响。仿真结果验证了理论分析的正确性。最后,针对广东某厂10kV、1MVA电力负荷,研制一套基于基波磁通补偿的串联混合型有源滤波器工程样机,取得非常好的滤波效果。
基金funded by Obayashi Corporation and the Consortium for Socio-functional Continuity Tech-nology(http://www.softech.titech.ac.jp/,Project ID:JPMJOP1723 un-der Japan Science and Technology Agency).
文摘Use of indices that quantify the seismic residual capacity of buildings damaged in earthquakes is one way to draw judgements on the building’s safety and possibility of future use.In Japanese damage assessment guidelines,several approximate calculation methods exist to evaluate the residual capacity of buildings based on visually observed damage and simplifying assumptions on the nature of the building’s response mechanism and member capacities.While these methods provide a useful residual capacity ratio that enables a‘relative’comparison be-tween buildings,the exact relationship to a physically meaningful residual capacity is unclear.The aim of this study is to benchmark the‘approximations’of residual capacity.To do so,a shake-table test was conducted on a 14 scale 4-storey RC structure and a residual capacity evaluation was undertaken based on observed damage states.With the help of a numerical model,a benchmark residual capacity at each of the damage states is determined and compared to the approximate residual capacity calculation results via guidelines.It was found that approx-imate methods are generally accurate prior to yield but can become overly conservative post-yield.Simplifying assumptions of equal member deformation capacity used in the residual capacity ratio calculation was found to be suitable given constraints of rapid field evaluations.
