An analysis applied to an existing building considering the whole service life, regulated or, if any, measured, of energy/technological upgrading action does not only require initial investments to be taken into accou...An analysis applied to an existing building considering the whole service life, regulated or, if any, measured, of energy/technological upgrading action does not only require initial investments to be taken into account. Of course, such investments are significant and will have to be considered at a first stage, but it is not the only aspect to be considered. Provisions of Construction Procurement Guidance, No.7 Whole Life Costs state: "All procurement must be made solely on the basis of value for money in terms of the optimum combination of global costs--and not only initial investment costs--and quality to meet the user's requirements".展开更多
Parameter identification, model calibration, and uncertainty quantification are important steps in the model-building process, and are necessary for obtaining credible results and valuable information. Sensitivity ana...Parameter identification, model calibration, and uncertainty quantification are important steps in the model-building process, and are necessary for obtaining credible results and valuable information. Sensitivity analysis of hydrological model is a key step in model uncertainty quantification, which can identify the dominant parameters, reduce the model calibration uncertainty, and enhance the model optimization efficiency. There are, however, some shortcomings in classical approaches, including the long duration of time and high computation cost required to quantitatively assess the sensitivity of a multiple-parameter hydrological model. For this reason, a two-step statistical evaluation framework using global techniques is presented. It is based on (1) a screening method (Morris) for qualitative ranking of parameters, and (2) a variance-based method integrated with a meta-model for quantitative sensitivity analysis, i.e., the Sobol method integrated with the response surface model (RSMSobol). First, the Morris screening method was used to qualitatively identify the parameters' sensitivity, and then ten parameters were selected to quantify the sensitivity indices. Subsequently, the RSMSobol method was used to quantify the sensitivity, i.e., the first-order and total sensitivity indices based on the response surface model (RSM) were calculated. The RSMSobol method can not only quantify the sensitivity, but also reduce the computational cost, with good accuracy compared to the classical approaches. This approach will be effective and reliable in the global sensitivity analysis of a complex large-scale distributed hydrological model.展开更多
In this study, a successful linear matrix inequality approach is used to analyse a non-parameter perturbation of multi-delay Hopfield neural network by constructing an appropriate Lyapunov-Krasovskii functional. This ...In this study, a successful linear matrix inequality approach is used to analyse a non-parameter perturbation of multi-delay Hopfield neural network by constructing an appropriate Lyapunov-Krasovskii functional. This paper presents the comprehensive discussion of the approach and also extensive applications.展开更多
In the post-pandemic era,the global economic and security landscapes are fraught with complexities and uncertainties.Among them,four risk flashpoints merit attention:Certain countries are raising interest rates to sub...In the post-pandemic era,the global economic and security landscapes are fraught with complexities and uncertainties.Among them,four risk flashpoints merit attention:Certain countries are raising interest rates to subdue inflation,despite their already high levels of debt;the bulk commodities market is experiencing volatility,leading to global turbulence and change;trade protectionism is at the forefront of major-power rivalry in political and economic spheres;and regional security crises are compounding international tensions.Behind those flashpoints are contradictions that obstruct world peace and progress,including development imbalances,governance gaps,and structural tensions in global security.In the face of uncertainties,it is crucial for China to seize strategic opportunities and transform crises into favorable situations.China has launched the Global Development Initiative(GDI)and the Global Security Initiative(GSI)to contribute to global prosperity and security.The two initiatives demonstrate China’s commitment to addressing global deficits in peace,development,security,and governance.展开更多
The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which triggered the ongoing pandemic,was first discovered in China in late 2019.SARSCoV-2 is a respiratory virus responsible for coronavirus diseas...The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which triggered the ongoing pandemic,was first discovered in China in late 2019.SARSCoV-2 is a respiratory virus responsible for coronavirus disease 2019(COVID-19)that often manifests as a pneumonic syndrome.In the context of the pandemic,there are mixed views on the data provided by epidemiologists and the information collected by hospital clinicians about their patients.In addition,the literature reports a large proportion of patients free of pneumonia vs a small percentage of patients with severe pneumonia among confirmed COVID-19 cases.This raises the issue of the complexity of the work required to control or contain the pandemic.We believe that an integrative and pluralistic approach will help to put the analyses into perspective and reinforce collaboration and creativity in the fight against this major scourge.This paper proposes a comprehensive and integrative approach to COVID-19 research,prevention,control,and treatment to better address the pandemic.Thus,this literature review applies a pluralistic approach to fight the pandemic.展开更多
Efficient bolted joint design is an essential part of designing the minimum weight aerospace structures, since structural failures usually occur at connections and interface. A comprehensive numerical study of three-d...Efficient bolted joint design is an essential part of designing the minimum weight aerospace structures, since structural failures usually occur at connections and interface. A comprehensive numerical study of three-dimensional(3D) stress variations is prohibitively expensive for a large-scale structure where hundreds of bolts can be present. In this work, the hybrid composite-to-metal bolted connections used in the upper stage of European Ariane 5ME rocket are analyzed using the global-local finite element(FE) approach which involves an approximate analysis of the whole structure followed by a detailed analysis of a significantly smaller region of interest. We calculate the Tsai-Wu failure index and the margin of safety using the stresses obtained from ABAQUS. We find that the composite part of a hybrid bolted connection is prone to failure compared to the metal part. We determine the bolt preload based on the clamp-up load calculated using a maximum preload to make the composite part safe. We conclude that the unsuitable bolt preload may cause the failure of the composite part due to the high stress concentration in the vicinity of the bolt. The global-local analysis provides an efficient computational tool for enhancing 3D stress analysis in the highly loaded region.展开更多
Firstly, the new combined error model of cumulative geoid height influenced by four error sources, including the inter-satellite range-rate of an interferometric laser (K-band) ranging system, the orbital position a...Firstly, the new combined error model of cumulative geoid height influenced by four error sources, including the inter-satellite range-rate of an interferometric laser (K-band) ranging system, the orbital position and velocity of a global positioning system (GPS) receiver and non-conservative force of an accelerometer, is established from the perspectives of the power spectrum principle in physics using the semi-analytical approach. Secondly, the accuracy of the global gravitational field is accurately and rapidly estimated based on the combined error model; the cumulative geoid height error is 1.985× 10^-1 m at degree 120 based on GRACE Level 1B measured observation errors of the year 2007 published by the US Jet Propulsion Laboratory (JPL), and the cumulative geoid height error is 5.825 × 10^-2 m at degree 360 using GRACE Follow-On orbital altitude 250 km and inter-satellite range 50 km. The matching relationship of accuracy indexes from GRACE Follow-On key payloads is brought forward, and the dependability of the combined error model is validated. Finally, the feasibility of high-accuracy and high-resolution global gravitational field estimation from GRACE Follow-On is demonstrated based on different satellite orbital altitudes.展开更多
By integrating the concept of cooperative approach, an extension of the fast annealing coevolutionary algorithm is presented in this paper. It outperformed the original algorithm in the domain of function optimization...By integrating the concept of cooperative approach, an extension of the fast annealing coevolutionary algorithm is presented in this paper. It outperformed the original algorithm in the domain of function optimization, especially in terms of convergence rate. It was also applied to a real optimization problem, protein motif extraction. And a satisfactory result has been obtained with the accuracy of prediction achieving 67.0%, which is in agreement with the result in the PROSITE database.展开更多
In this paper, we shall establish some global existence results for the higherdimensional nonhomogeneous, linear, semilinear and nonlinear Thermoelastic plates with memory respectively by using semigroup approach. The...In this paper, we shall establish some global existence results for the higherdimensional nonhomogeneous, linear, semilinear and nonlinear Thermoelastic plates with memory respectively by using semigroup approach. The existence and decay of solutions of homogeneous linear problem has been solved by Romero [1] .展开更多
Global change research and sustainable development need to be addressed at larger scales in the light of small scale process studies. Much remains to be done before the small scale, process level understanding of ecos...Global change research and sustainable development need to be addressed at larger scales in the light of small scale process studies. Much remains to be done before the small scale, process level understanding of ecosystem responses to global change can be reliably translated to larger scales. The paper reviews the status of scaling issues and tries to find how to extrapolate our observations and our findings at site scale up to regional scale and provide ecological information and interpretations at the regional scale. An integrated approach to scaling-up from site to region is proposed combining hierarchical theory, landscape ecology, remote sensing, geographical information system (GIS) with process/mechanistic modeling. Remote sensing and GIS will play key roles in spatial analysis, integration as well as cross scale modeling.展开更多
文摘An analysis applied to an existing building considering the whole service life, regulated or, if any, measured, of energy/technological upgrading action does not only require initial investments to be taken into account. Of course, such investments are significant and will have to be considered at a first stage, but it is not the only aspect to be considered. Provisions of Construction Procurement Guidance, No.7 Whole Life Costs state: "All procurement must be made solely on the basis of value for money in terms of the optimum combination of global costs--and not only initial investment costs--and quality to meet the user's requirements".
基金supported by the National Natural Science Foundation of China (Grant No. 41271003)the National Basic Research Program of China (Grants No. 2010CB428403 and 2010CB951103)
文摘Parameter identification, model calibration, and uncertainty quantification are important steps in the model-building process, and are necessary for obtaining credible results and valuable information. Sensitivity analysis of hydrological model is a key step in model uncertainty quantification, which can identify the dominant parameters, reduce the model calibration uncertainty, and enhance the model optimization efficiency. There are, however, some shortcomings in classical approaches, including the long duration of time and high computation cost required to quantitatively assess the sensitivity of a multiple-parameter hydrological model. For this reason, a two-step statistical evaluation framework using global techniques is presented. It is based on (1) a screening method (Morris) for qualitative ranking of parameters, and (2) a variance-based method integrated with a meta-model for quantitative sensitivity analysis, i.e., the Sobol method integrated with the response surface model (RSMSobol). First, the Morris screening method was used to qualitatively identify the parameters' sensitivity, and then ten parameters were selected to quantify the sensitivity indices. Subsequently, the RSMSobol method was used to quantify the sensitivity, i.e., the first-order and total sensitivity indices based on the response surface model (RSM) were calculated. The RSMSobol method can not only quantify the sensitivity, but also reduce the computational cost, with good accuracy compared to the classical approaches. This approach will be effective and reliable in the global sensitivity analysis of a complex large-scale distributed hydrological model.
基金Project supported by the National Natural Science Foundations of China (Grant Nos. 70571030 and 90610031)the Society Science Foundation from Ministry of Education of China (Grant No. 08JA790057)the Advanced Talents’ Foundation and Student’s Foundation of Jiangsu University (Grant Nos. 07JDG054 and 07A075)
文摘In this study, a successful linear matrix inequality approach is used to analyse a non-parameter perturbation of multi-delay Hopfield neural network by constructing an appropriate Lyapunov-Krasovskii functional. This paper presents the comprehensive discussion of the approach and also extensive applications.
基金supported by the key project of the National Social Science Fund of China(NSSFC):“Study on China-Russia Strategic Partnership for the New Era”(Grant No.20AGJ012).
文摘In the post-pandemic era,the global economic and security landscapes are fraught with complexities and uncertainties.Among them,four risk flashpoints merit attention:Certain countries are raising interest rates to subdue inflation,despite their already high levels of debt;the bulk commodities market is experiencing volatility,leading to global turbulence and change;trade protectionism is at the forefront of major-power rivalry in political and economic spheres;and regional security crises are compounding international tensions.Behind those flashpoints are contradictions that obstruct world peace and progress,including development imbalances,governance gaps,and structural tensions in global security.In the face of uncertainties,it is crucial for China to seize strategic opportunities and transform crises into favorable situations.China has launched the Global Development Initiative(GDI)and the Global Security Initiative(GSI)to contribute to global prosperity and security.The two initiatives demonstrate China’s commitment to addressing global deficits in peace,development,security,and governance.
文摘The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which triggered the ongoing pandemic,was first discovered in China in late 2019.SARSCoV-2 is a respiratory virus responsible for coronavirus disease 2019(COVID-19)that often manifests as a pneumonic syndrome.In the context of the pandemic,there are mixed views on the data provided by epidemiologists and the information collected by hospital clinicians about their patients.In addition,the literature reports a large proportion of patients free of pneumonia vs a small percentage of patients with severe pneumonia among confirmed COVID-19 cases.This raises the issue of the complexity of the work required to control or contain the pandemic.We believe that an integrative and pluralistic approach will help to put the analyses into perspective and reinforce collaboration and creativity in the fight against this major scourge.This paper proposes a comprehensive and integrative approach to COVID-19 research,prevention,control,and treatment to better address the pandemic.Thus,this literature review applies a pluralistic approach to fight the pandemic.
基金Project(282522)supported by the European Union's Research and Innovation Funding Programme
文摘Efficient bolted joint design is an essential part of designing the minimum weight aerospace structures, since structural failures usually occur at connections and interface. A comprehensive numerical study of three-dimensional(3D) stress variations is prohibitively expensive for a large-scale structure where hundreds of bolts can be present. In this work, the hybrid composite-to-metal bolted connections used in the upper stage of European Ariane 5ME rocket are analyzed using the global-local finite element(FE) approach which involves an approximate analysis of the whole structure followed by a detailed analysis of a significantly smaller region of interest. We calculate the Tsai-Wu failure index and the margin of safety using the stresses obtained from ABAQUS. We find that the composite part of a hybrid bolted connection is prone to failure compared to the metal part. We determine the bolt preload based on the clamp-up load calculated using a maximum preload to make the composite part safe. We conclude that the unsuitable bolt preload may cause the failure of the composite part due to the high stress concentration in the vicinity of the bolt. The global-local analysis provides an efficient computational tool for enhancing 3D stress analysis in the highly loaded region.
基金supported by the National Natural Science Foundation of China (Grant No 40674038)the Funds of the Chinese Academy of Sciences for Key Topics in Innovation Engineering (Grant Nos KZCX2-YW-143 and KZCX2-YW-202)+1 种基金the National High Technology Research and Development Program of China (863) (Grant Nos 2009AA12Z138 and 2006AA09Z153)the Grant-in-Aid for Scientific Research of Japan (Grant No B19340129)
文摘Firstly, the new combined error model of cumulative geoid height influenced by four error sources, including the inter-satellite range-rate of an interferometric laser (K-band) ranging system, the orbital position and velocity of a global positioning system (GPS) receiver and non-conservative force of an accelerometer, is established from the perspectives of the power spectrum principle in physics using the semi-analytical approach. Secondly, the accuracy of the global gravitational field is accurately and rapidly estimated based on the combined error model; the cumulative geoid height error is 1.985× 10^-1 m at degree 120 based on GRACE Level 1B measured observation errors of the year 2007 published by the US Jet Propulsion Laboratory (JPL), and the cumulative geoid height error is 5.825 × 10^-2 m at degree 360 using GRACE Follow-On orbital altitude 250 km and inter-satellite range 50 km. The matching relationship of accuracy indexes from GRACE Follow-On key payloads is brought forward, and the dependability of the combined error model is validated. Finally, the feasibility of high-accuracy and high-resolution global gravitational field estimation from GRACE Follow-On is demonstrated based on different satellite orbital altitudes.
基金This work was supported by the National Natural Science Foundation of China (No.20475068, 20575082) the Natural Science Foundation of Guangdong Province (No.031577) the Scientific Technology Project of Guangdong Province (No.2005B30101003).
文摘By integrating the concept of cooperative approach, an extension of the fast annealing coevolutionary algorithm is presented in this paper. It outperformed the original algorithm in the domain of function optimization, especially in terms of convergence rate. It was also applied to a real optimization problem, protein motif extraction. And a satisfactory result has been obtained with the accuracy of prediction achieving 67.0%, which is in agreement with the result in the PROSITE database.
基金Supported by the NNSF of China(10871040)Supported by the Foundation of Shanghai(QD210006)
文摘In this paper, we shall establish some global existence results for the higherdimensional nonhomogeneous, linear, semilinear and nonlinear Thermoelastic plates with memory respectively by using semigroup approach. The existence and decay of solutions of homogeneous linear problem has been solved by Romero [1] .
基金the Important Directional Project of Knowledge Innovation of the Chinese Academy of Sciences (No: KZCX2-308-4).
文摘Global change research and sustainable development need to be addressed at larger scales in the light of small scale process studies. Much remains to be done before the small scale, process level understanding of ecosystem responses to global change can be reliably translated to larger scales. The paper reviews the status of scaling issues and tries to find how to extrapolate our observations and our findings at site scale up to regional scale and provide ecological information and interpretations at the regional scale. An integrated approach to scaling-up from site to region is proposed combining hierarchical theory, landscape ecology, remote sensing, geographical information system (GIS) with process/mechanistic modeling. Remote sensing and GIS will play key roles in spatial analysis, integration as well as cross scale modeling.