Given the challenges facing most humanitarian operations worldwide, a change of approach is needed to ensure greater sustainability of humanitarian settlements right from the planning stage. Some studies attribute uns...Given the challenges facing most humanitarian operations worldwide, a change of approach is needed to ensure greater sustainability of humanitarian settlements right from the planning stage. Some studies attribute unsustainability to inadequate provision of basic resources and highlight the apparent bottlenecks that prevent access to the meaningful data needed to plan and remedy problems. Most operations have relied on an “ad hoc ism” approach, employing parallel and disconnected data processing methods, resulting in a wide range of data being collected without subsequent prioritization to optimize interconnections that could enhance performance. There have been little efforts to study the trade-offs potentially at stake. This work proposes a new framework enabling all subsystems to operate in a single system and focusing on data processing perspective. To achieve this, this paper proposes a Triple Nexus Framework as an attempt to integrate water, energy, and housing sector data derived from a specific sub-system within the overall system in the application of Model-Based Systems Engineering. Understanding the synergies between water, energy, and housing, Systems Engineering characterizes the triple nexus framework and identifies opportunities for improved decision-making in processing operational data from these sectors. Two scenarios illustrate how an integrated platform could be a gateway to access meaningful operational data in the system and a starting point for modeling integrated human settlement systems. Upon execution, the model is tested for nexus megadata processing, and the optimization simulation yielded 67% satisfactory results, demonstrating that an integrated system could improve sustainability, and that capacity building in service delivery is more than beneficial.展开更多
Food,energy and water(FEW)are indispensable,irreplaceable and safeguarding resources with tangled interlinkages among each other,often framed in terms of‘nexus’.Cities have become the bustling hubs of resource consu...Food,energy and water(FEW)are indispensable,irreplaceable and safeguarding resources with tangled interlinkages among each other,often framed in terms of‘nexus’.Cities have become the bustling hubs of resource consumption and production,facing the most intense stress.Globally,food security,fresh water shortage and fossil energy exhaustion have become the greatest challenge for the sustainable development of cities in the future.Systematic analysis and simulation of dynamic evolution of urban FEW demand and supply and its nexus would add significant and practical value for macro-management such as ensuring the security of urban resource.Taking Beijing as the case study,we established a dynamic model for the FEW demand and supply from the perspective of cross-ectoral and cross-regional nexus with the Stella modelling platform,then it was run for simulating the dynamic changes and nexus characteristics of FEW during the interval between 2016 and 2035.The results showed that:①The gap between local production and demand of these three resources in Beijing will continue to increase.In 2035,Beijing will need 2.16 million tons of grain,0.83 million tons of meat,4.6 billion m3 of water and 91.65 million tons of standard coal of energy while the resources produced and supplied by locality independently will be 0.21 million tons,0.23 million tons,3.3 billion cubic meters and 16.5 million tons of standard coal respectively.Beijing has to draw on cross-boundary production to meet FEW-use with the increasing gap between local supply and demand.②There is a developing trend of the absolute quantity of interaction among FEW.Structurally,the‘outsourcing’feature is obvious and the indigenous nexus links of three resources are shifting to back-end supply chain such as transportation and treatment.③The change of nexus indexes are mainly affected by the mutual and strong dependence between food and water.Food and energy depend more and more on each other;in contrast,the inter-relationship between water and energy is more stable.In addition,inter-regional FEW nexus is strengthened.④To improve systematic management of urban resources,we need to capture multi-tradeoffs of the FEW system comprehensively and establish a multi-regional and multi-factor integrated and collaborative resource management mechanism.展开更多
Water, Energy and Food (WEF) nexus systems are developed to model and analyze interactions across and between WEF sectors. WEF nexus simulation models permit evaluating the direct and indirect WEF quantitative interac...Water, Energy and Food (WEF) nexus systems are developed to model and analyze interactions across and between WEF sectors. WEF nexus simulation models permit evaluating the direct and indirect WEF quantitative interaction effects in response to change of technology and/or demand. Optimization models can help to find the optimal combinations of WEF nexus system policy options and parameters that lead to the best performance of the system. This paper describes a framework for integrating quantitative WEF nexus simulation model (the Q-Nexus Model) with an optimization tool, which will give policy makers the ability to compromise best policy options based on WEF nexus simulator. The developed method is then applied to the numerical experiment and the results are discussed. Lastly, the conclusions and further developments are presented.展开更多
The quantitative assessment framework of the water, energy and food (WEF) nexus proposed by [1] permits the analysis of the WEF as an interconnected system of resources that directly and indirectly affect one another....The quantitative assessment framework of the water, energy and food (WEF) nexus proposed by [1] permits the analysis of the WEF as an interconnected system of resources that directly and indirectly affect one another. The model performs simulation of policy options and scenarios that respond to quantitative variations of the use of WEF resources. One of the key outcomes of the mathematical formulation of the model is the WEF nexus intersectoral technology matrix. In order to take advantages and analyzing policy options of adopting high efficient intersectoral use technologies, WEF intersectoral use intensities and intersectoral allocation coefficients are introduced to the technology matrix of the nexus model proposed in [1]. The developed method is then applied to evaluate the WEF nexus case study of Lebanon. Lastly, the conclusions and further developments are presented.展开更多
The Urban Nexus system creates another risk characteristic of resource metabolism. Urban metabolism has complex effects from multi-levels and multi-sectors resulted from the changes socio-economic. It is crucial to im...The Urban Nexus system creates another risk characteristic of resource metabolism. Urban metabolism has complex effects from multi-levels and multi-sectors resulted from the changes socio-economic. It is crucial to implement effective urban governance;in particular, resource metabolism creates a new nexus risk by dramatic growth in urban areas. The resource metabolism associates with water, energy, and food consumption on an urban scale that drives the intensity in resource metabolism. Therefore, this study estimates the FEW intensity of the nexus and demand side in material flow analysis by organizing into four categories of resource metabolism, including supply side, process side, demand side, and final sink. This research compares different characteristics for a small island dominated by tourism and a multi-sector city dominated by increasing economic activity. The resource intensity on the demand side and resource service systems are evaluated to identify the nexus intensity and risk for FEW nexus at the urban scale. This study determines that constraints for resource service systems are complex, and suggests that resource consumption intensity is higher in that particular nexus and demand sector. To avoid excessive loads on resource metabolism, sustainable resource management should implement trade-off strategies after analyzing the resource metabolism for urban nexus.展开更多
This paper presents a quantitative assessment framework of the Water, Energy and Food (W-E-F) nexus. The proposed approach allows integrated quantitative assessments by considering all the W-E-F intersectoral linkages...This paper presents a quantitative assessment framework of the Water, Energy and Food (W-E-F) nexus. The proposed approach allows integrated quantitative assessments by considering all the W-E-F intersectoral linkages and the competing demand for W-E-F resources to evaluate future development scenarios. Firstly, the conceptual model adopted for the proposed framework is presented. Secondly, a detailed methodological framework is introduced to serve as W-E-F nexus evaluation and planning platform. At the practical level, the model is applied to evaluate the W-E-F nexus in Lebanon. Finally, the conclusions and further developments are presented.展开更多
在本文上篇完成以后，围绕着iPhone发生了两件大事。一是苹果正式发布了iPhone OS 4，增加了多任务能力；二是下一代iPhone被意外曝光，除了造型变化外，硬件规格大有赶超Nexus One之势。这也意味着，iPhone和Android手机的较量将更多...在本文上篇完成以后，围绕着iPhone发生了两件大事。一是苹果正式发布了iPhone OS 4，增加了多任务能力；二是下一代iPhone被意外曝光，除了造型变化外，硬件规格大有赶超Nexus One之势。这也意味着，iPhone和Android手机的较量将更多取决于综合实力。展开更多
Stem cell fate determination is one of the central questions in stem cell biology,and although its regulation has been studied at genomic and proteomic levels,a variety of biological activities in cells occur at the m...Stem cell fate determination is one of the central questions in stem cell biology,and although its regulation has been studied at genomic and proteomic levels,a variety of biological activities in cells occur at the metabolic level.Metabolomics studies have established the metabolome during stem cell differentiation and have revealed the role of metabolites in stem cell fate determination.While metabolism is considered to play a biological regulatory role as an energy source,recent studies have suggested the nexus between metabolism and epigenetics because several metabolites function as cofactors and substrates in epigenetic mechanisms,including histone modification,DNA methylation,and microRNAs.Additionally,the epigenetic modification is sensitive to the dynamic metabolites and consequently leads to changes in transcription.The nexus between metabolism and epigenetics proposes a novel stem cell-based therapeutic strategy through manipulating metabolites.In the present review,we summarize the possible nexus between metabolic and epigenetic regulation in stem cell fate determination,and discuss the potential preventive and therapeutic strategies via targeting metabolites.展开更多
文摘Given the challenges facing most humanitarian operations worldwide, a change of approach is needed to ensure greater sustainability of humanitarian settlements right from the planning stage. Some studies attribute unsustainability to inadequate provision of basic resources and highlight the apparent bottlenecks that prevent access to the meaningful data needed to plan and remedy problems. Most operations have relied on an “ad hoc ism” approach, employing parallel and disconnected data processing methods, resulting in a wide range of data being collected without subsequent prioritization to optimize interconnections that could enhance performance. There have been little efforts to study the trade-offs potentially at stake. This work proposes a new framework enabling all subsystems to operate in a single system and focusing on data processing perspective. To achieve this, this paper proposes a Triple Nexus Framework as an attempt to integrate water, energy, and housing sector data derived from a specific sub-system within the overall system in the application of Model-Based Systems Engineering. Understanding the synergies between water, energy, and housing, Systems Engineering characterizes the triple nexus framework and identifies opportunities for improved decision-making in processing operational data from these sectors. Two scenarios illustrate how an integrated platform could be a gateway to access meaningful operational data in the system and a starting point for modeling integrated human settlement systems. Upon execution, the model is tested for nexus megadata processing, and the optimization simulation yielded 67% satisfactory results, demonstrating that an integrated system could improve sustainability, and that capacity building in service delivery is more than beneficial.
基金This work was supported by the Funds for National Science and Technology Major Project of the Ministry of Science and Technology of China[Grant number.2017YFC0505703]National Natural Science Foundation of China[Grant number.52070022]Sino Italian Cooperation of China Natural Science Foundation[Grant number.71861137001].
文摘Food,energy and water(FEW)are indispensable,irreplaceable and safeguarding resources with tangled interlinkages among each other,often framed in terms of‘nexus’.Cities have become the bustling hubs of resource consumption and production,facing the most intense stress.Globally,food security,fresh water shortage and fossil energy exhaustion have become the greatest challenge for the sustainable development of cities in the future.Systematic analysis and simulation of dynamic evolution of urban FEW demand and supply and its nexus would add significant and practical value for macro-management such as ensuring the security of urban resource.Taking Beijing as the case study,we established a dynamic model for the FEW demand and supply from the perspective of cross-ectoral and cross-regional nexus with the Stella modelling platform,then it was run for simulating the dynamic changes and nexus characteristics of FEW during the interval between 2016 and 2035.The results showed that:①The gap between local production and demand of these three resources in Beijing will continue to increase.In 2035,Beijing will need 2.16 million tons of grain,0.83 million tons of meat,4.6 billion m3 of water and 91.65 million tons of standard coal of energy while the resources produced and supplied by locality independently will be 0.21 million tons,0.23 million tons,3.3 billion cubic meters and 16.5 million tons of standard coal respectively.Beijing has to draw on cross-boundary production to meet FEW-use with the increasing gap between local supply and demand.②There is a developing trend of the absolute quantity of interaction among FEW.Structurally,the‘outsourcing’feature is obvious and the indigenous nexus links of three resources are shifting to back-end supply chain such as transportation and treatment.③The change of nexus indexes are mainly affected by the mutual and strong dependence between food and water.Food and energy depend more and more on each other;in contrast,the inter-relationship between water and energy is more stable.In addition,inter-regional FEW nexus is strengthened.④To improve systematic management of urban resources,we need to capture multi-tradeoffs of the FEW system comprehensively and establish a multi-regional and multi-factor integrated and collaborative resource management mechanism.
文摘Water, Energy and Food (WEF) nexus systems are developed to model and analyze interactions across and between WEF sectors. WEF nexus simulation models permit evaluating the direct and indirect WEF quantitative interaction effects in response to change of technology and/or demand. Optimization models can help to find the optimal combinations of WEF nexus system policy options and parameters that lead to the best performance of the system. This paper describes a framework for integrating quantitative WEF nexus simulation model (the Q-Nexus Model) with an optimization tool, which will give policy makers the ability to compromise best policy options based on WEF nexus simulator. The developed method is then applied to the numerical experiment and the results are discussed. Lastly, the conclusions and further developments are presented.
文摘The quantitative assessment framework of the water, energy and food (WEF) nexus proposed by [1] permits the analysis of the WEF as an interconnected system of resources that directly and indirectly affect one another. The model performs simulation of policy options and scenarios that respond to quantitative variations of the use of WEF resources. One of the key outcomes of the mathematical formulation of the model is the WEF nexus intersectoral technology matrix. In order to take advantages and analyzing policy options of adopting high efficient intersectoral use technologies, WEF intersectoral use intensities and intersectoral allocation coefficients are introduced to the technology matrix of the nexus model proposed in [1]. The developed method is then applied to evaluate the WEF nexus case study of Lebanon. Lastly, the conclusions and further developments are presented.
文摘The Urban Nexus system creates another risk characteristic of resource metabolism. Urban metabolism has complex effects from multi-levels and multi-sectors resulted from the changes socio-economic. It is crucial to implement effective urban governance;in particular, resource metabolism creates a new nexus risk by dramatic growth in urban areas. The resource metabolism associates with water, energy, and food consumption on an urban scale that drives the intensity in resource metabolism. Therefore, this study estimates the FEW intensity of the nexus and demand side in material flow analysis by organizing into four categories of resource metabolism, including supply side, process side, demand side, and final sink. This research compares different characteristics for a small island dominated by tourism and a multi-sector city dominated by increasing economic activity. The resource intensity on the demand side and resource service systems are evaluated to identify the nexus intensity and risk for FEW nexus at the urban scale. This study determines that constraints for resource service systems are complex, and suggests that resource consumption intensity is higher in that particular nexus and demand sector. To avoid excessive loads on resource metabolism, sustainable resource management should implement trade-off strategies after analyzing the resource metabolism for urban nexus.
文摘This paper presents a quantitative assessment framework of the Water, Energy and Food (W-E-F) nexus. The proposed approach allows integrated quantitative assessments by considering all the W-E-F intersectoral linkages and the competing demand for W-E-F resources to evaluate future development scenarios. Firstly, the conceptual model adopted for the proposed framework is presented. Secondly, a detailed methodological framework is introduced to serve as W-E-F nexus evaluation and planning platform. At the practical level, the model is applied to evaluate the W-E-F nexus in Lebanon. Finally, the conclusions and further developments are presented.
基金Supported by the National Natural Science Foundation of China (General Program),No. 82170921the Sichuan Science and Technology Program,No. 2022YFS0284the Research and Develop Program,West China Hospital of Stomatology Sichuan University,No. LCYJ2019-24
文摘Stem cell fate determination is one of the central questions in stem cell biology,and although its regulation has been studied at genomic and proteomic levels,a variety of biological activities in cells occur at the metabolic level.Metabolomics studies have established the metabolome during stem cell differentiation and have revealed the role of metabolites in stem cell fate determination.While metabolism is considered to play a biological regulatory role as an energy source,recent studies have suggested the nexus between metabolism and epigenetics because several metabolites function as cofactors and substrates in epigenetic mechanisms,including histone modification,DNA methylation,and microRNAs.Additionally,the epigenetic modification is sensitive to the dynamic metabolites and consequently leads to changes in transcription.The nexus between metabolism and epigenetics proposes a novel stem cell-based therapeutic strategy through manipulating metabolites.In the present review,we summarize the possible nexus between metabolic and epigenetic regulation in stem cell fate determination,and discuss the potential preventive and therapeutic strategies via targeting metabolites.
