As a kind of clean energy which creates little carbon dioxide, natural gas will play a key role in the process of achieving “Peak Carbon Dioxide Emission” and “Carbon Neutrality”. The Long-range Energy Alternative...As a kind of clean energy which creates little carbon dioxide, natural gas will play a key role in the process of achieving “Peak Carbon Dioxide Emission” and “Carbon Neutrality”. The Long-range Energy Alternatives Planning System(LEAP) model was improved by using new parameters including comprehensive energy efficiency and terminal effective energy consumption. The Back Propagation(BP) Neural Network–LEAP model was proposed to predict key data such as total primary energy consumption, energy mix, carbon emissions from energy consumption, and natural gas consumption in China. Moreover, natural gas production in China was forecasted by the production composition method. Finally, based on the forecast results of natural gas supply and demand, suggestions were put forward on the development of China’s natural gas industry under the background of “Dual Carbon Targets”. The research results indicate that under the background of carbon peak and carbon neutrality, China’s primary energy consumption will peak(59.4×10^(8)tce) around 2035, carbon emissions from energy consumption will peak(103.4×10^(8)t) by 2025, and natural gas consumption will peak(6100×10^(8)m^(3)) around 2040, of which the largest increase will be contributed by the power sector and industrial sector. China’s peak natural gas production is about(2800–3400)×10^(8)m^(3), including(2100–2300)×10^(8)m^(3)conventional gas(including tight gas),(600–1050)×10^(8)m^(3)shale gas, and(150–220)×10^(8)m^(3)coalbed methane. Under the background of carbon peak and carbon neutrality, the natural gas consumption and production of China will further increase, showing a great potential of the natural gas industry.展开更多
The oxygen evolution reaction(OER)is the essential module in energy conversion and storage devices such as electrolyzer,rechargeable metal–air batteries and regenerative fuel cells.The adsorption energy scaling relat...The oxygen evolution reaction(OER)is the essential module in energy conversion and storage devices such as electrolyzer,rechargeable metal–air batteries and regenerative fuel cells.The adsorption energy scaling relations between the reaction intermediates,however,impose a large intrinsic overpotential and sluggish reaction kinetics on OER catalysts.Developing advanced electrocatalysts with high activity and stability based on non-noble metal materials is still a grand challenge.Central to the rational design of novel and high-efficiency catalysts is the development and understanding of quantitative structure–activity relationships,which correlate the catalytic activities with structural and electronic descriptors.This paper comprehensively reviews the benchmark descriptors for OER electrolysis,aiming to give an in-depth understanding on the origins of the electrocatalytic activity of the OER and further contribute to building the theory of electrocatalysis.Meanwhile,the cutting-edge research frontiers for proposing new OER paradigms and crucial strategies to circumvent the scaling relationship are also summarized.Challenges,opportunities and perspectives are discussed,intending to shed some light on the rational design concepts and advance the development of more efficient catalysts for enhancing OER performance.展开更多
This paper reviews literature on the relationship between food supply and obesity. The focus is on the supply, cost, and variety of food through various types of food outlets and the impact of these factors on obesity...This paper reviews literature on the relationship between food supply and obesity. The focus is on the supply, cost, and variety of food through various types of food outlets and the impact of these factors on obesity in developed countries. The article reveals complex relationships between food supply factors and obesity. A numer of factors related to lifestyles including the mobility of populations and the use of motor vehicles greatly reduce the impact of the local environment on family and individual eating patterns. However, obesity is also affected by factors such as the type and density of food outlets, the cost of food, the travel distance and means of transport to the food outlet. While the relationship between food supply and obesity in the literature reveals complex and mixed findings, this paper concludes obesity is complex and food supply is only part of this phenomenon’s predictors. Because the relationship between food supply and obesity is mediated by such multiple and complex factors including population behaviours, beliefs, lifestyles, knowledge and both food and physical environments;multiple strategies including policy development and other strategies aimed at manipulating food environments, physical environments, populations’ beliefs, behaviours and practices must be considered in searching for evidence to effectively combat obesity.展开更多
Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin,which is taken as a study case in this paper.It is still not clear how the secondary stora...Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin,which is taken as a study case in this paper.It is still not clear how the secondary storage space shape influences the P-& S-wave velocities (or elastic properties) in complex carbonate reservoirs.In this paper,three classical rock physics models (Wyllie timeaverage equation,Gassmann equation and the Kuster-Toks z model) are comparably analyzed for their construction principles and actual velocity prediction results,aiming at determining the most favourable rock physics model to consider the influence of secondary storage space shape.Then relationships between the P-& S-wave velocities in carbonate reservoirs and geometric shapes of secondary storage spaces are discussed from different aspects based on actual well data by employing the favourable rock physics model.To explain the influence of secondary storage space shape on V P-V S relationship,it is analyzed for the differences of S-wave velocities between derived from common empirical relationships (including Castagna's mud rock line and Greenberg-Castagna V P-V S relationship) and predicted by the rock physics model.We advocate that V P-V S relationship for complex carbonate reservoirs should be built for different storage space types.For the carbonate reservoirs in the Tarim Basin,the V P-V S relationships for fractured,fractured-cavernous,and fractured-hole-vuggy reservoirs are respectively built on the basis of velocity prediction and secondary storage space type determination.Through the discussion above,it is expected that the velocity prediction and the V P-V S relationships for complex carbonate reservoirs should fully consider the influence of secondary storage space shape,thus providing more reasonable constraints for prestack inversion,further building a foundation for realizing carbonate reservoir prediction and fluid prediction.展开更多
In response to the underutilization of energy and insufficient flexible operation capability of rural energy supply systems in China,this study proposes an optimal dispatch approach for a rural multi-energy supply sys...In response to the underutilization of energy and insufficient flexible operation capability of rural energy supply systems in China,this study proposes an optimal dispatch approach for a rural multi-energy supply system(RMESS)considering virtual energy storage(VES).First,to enable the flexible utilization of rural biomass resources and the thermal inertia of residential building envelopes,this study constructed VES-I and VES-II models that describe electrical-thermal and electrical-gas coupling from an electrical viewpoint.Subsequently,an RMESS model encompassing these two types of VES was formulated.This model delineates the intricate interplay of multi-energy components within the RMESS framework and facilitates the precise assessment of the adjustable potential for optimizing RMESS operations.Based on the above models,a day-ahead optimal dispatch model for an RMESS considering a VES is proposed to achieve optimal economic performance while ensuring efficient energy allocation.Comparative simulations validated the effectiveness of the VES modeling and the day-ahead optimal dispatch approach for the RMESS.展开更多
Dairy industry is the pillar of Heilongjiang Province. The contractual relationship of the dairy supply chain played a vital role in the dairy industry for development. The contractual relationship between the main da...Dairy industry is the pillar of Heilongjiang Province. The contractual relationship of the dairy supply chain played a vital role in the dairy industry for development. The contractual relationship between the main dairy farming body and the dairy processing enterprise, as well as the impact of this contractual relationship on their cooperation in dairy supply chain were studied. Taking 366 dairy farming bodies in Heilongjiang Province as the main research objects, Likert scale was used to measure the factors affecting the contractual relationship and applied these factors to the correlation construction of dairy farming body and processing enterprise. Then, confirmatory factor analysis was used to collect data and made the conclusion that once dairy farming body perceived the opportunistic behavior and lacking of cooperation, the trust of dairy processing enterprise would be lost. Additionally, the satisfaction of dairy farming body on partnership also had a positive effect on the level of trust and commitment, the relative dependence and the perception of the partnerships, which made it possible to analyze how to strengthen the contractual relationship and provide theoretical basis for dairy industry development in Heilongjiang Province.展开更多
This paper examines the optimal forecast-sharing strategy in a hybrid-format online platform supply chain where a supplier sells a product through agency format and reselling format provided by a platform retailer who...This paper examines the optimal forecast-sharing strategy in a hybrid-format online platform supply chain where a supplier sells a product through agency format and reselling format provided by a platform retailer who possesses demand forecasts from two channels.Forecast asymmetry and co-opetitive relationship arise between the platform retailer and the supplier,which affect their operational decisions and the supply chain’s performance.To improve supply chain efficiency,we compare different forecast-sharing strategies(i.e.,no forecast sharing,sharing a single forecast,and sharing two forecasts),and analyze the effects of co-opetitive parameters on the optimal forecast-sharing strategy.Our analysis shows that forecast sharing is always beneficial to the supplier,and sharing two forecasts is more beneficial than sharing a single forecast.Whereas for the platform retailer and the whole supply chain,forecast sharing is beneficial only under certain conditions,depending on the co-opetitive parameters.The optimal forecast-sharing strategy is the result of a combination of the negative effect of double marginalization in reselling channel and the positive effect of responding pricing to demand uncertainty in agency channel.We illustrate the parameter regions of the platform retailer’s voluntary sharing,contract sharing,and no sharing,and also find that higher channel competition intensity,higher market share of agency channel,and higher commission rate can promote the platform retailer’s voluntary sharing.Our study extends the research scope of demand forecast-sharing and sheds light on the decision-making processes for managing a hybrid-format online platform supply chain.展开更多
In this study,the present situation and characteristics of power supply in remote areas are summarized.By studying the cases of power supply projects in remote areas,the experience is analyzed and described,and the ap...In this study,the present situation and characteristics of power supply in remote areas are summarized.By studying the cases of power supply projects in remote areas,the experience is analyzed and described,and the applicability of related technologies,such as grid-forming storage and power load management,is studied,including grid-connection technologies,such as grid-forming converters and power load management.On this basis,three power-supply modes were proposed.The application scenarios and advantages of the three modes were compared and analyzed.Based on the local development situation,the temporal sequences of the three schemes are described,and a case study was conducted.The study of the heavy-load power supply mode in remote areas contributes to solving the problem of heavy-load green power consumption in remote areas and promoting the further development of renewable energy.展开更多
Crystal structure determines electrochemical energy storage characteristics;this is the underlying logic of material design.To date,hundreds of electrode materials have been developed to pursue superior performance.Ho...Crystal structure determines electrochemical energy storage characteristics;this is the underlying logic of material design.To date,hundreds of electrode materials have been developed to pursue superior performance.However,it remains a great challenge to understand the fundamental structure–performance relationship and achieve quantitative crystal structure design for efficient energy storage.In this review,we introduce the concept of crystal packing factor(PF),which can quantify crystal packing density.We then present and classify the typical crystal structures of attractive cathode/anode materials.Comparative PF analyses of different materials,including polymorphs,isomorphs,and others,are performed to clarify the influence of crystal packing density on energy storage performance through electronic and ionic conductivities.Notably,the practical electronic/ionic conductivities of energy storage materials are based on their intrinsic characteristics related to the PF yet are also affected by extrinsic factors.The PF provides a novel avenue for understanding the electrochemical performance of pristine materials and may offer guidance on designing better materials.Additional approaches involve size regulation,doping,carbon additives,and other methods.We also propose extended PF concepts to understand charge storage and transport behavior at different scales.Finally,we provide our insights on the major challenges and prospective solutions in this highly exciting field.展开更多
Caspian Gas into Balkans over medium to long term becames Albanian case on June 2013 when TAP route was selected. After Albanian National Territory Council approved TAP AG's Compound Development Permit, the project s...Caspian Gas into Balkans over medium to long term becames Albanian case on June 2013 when TAP route was selected. After Albanian National Territory Council approved TAP AG's Compound Development Permit, the project should start Construction Phase 1. Existing gas pipeline connections of Albania within the European network via TAP, is highly estimated by energy authorities in both technical and regulating aspects. New pipelines are projected to be build in order to meet local energy consume and seasonal fluctuations, as well as needs of Kosovo and FYROM. Some of important points: determination on the capacity sector building for a due Albanian Gas Market Model, supply options on the future gasification, alternatives of opening underground gas storages in the salt domes of Dumre region and extending pipelines to neighboring countries. By assistance of the Secretariat of Energy Community, MEI starts drafting the new gas law to meet Third Energy Package. TAP project, IAP project, Albania-Kosovo Pipeline, an LNG plant and terminals coastal construction, can contribute on the diversification of gas supply. Underground Gas Storage potentials are geologic solution target, considering the Upper Miocene depleted sandstone gas fields of Divjaka, as well as the Dumre evaporitic deposits diapir of the Upper Triassic.展开更多
Managing supply chain partnerships for competitive advantage is receiving considerable recognition among both academic researchers and industry executives. Trust is an essential factor for a company to collaborate wit...Managing supply chain partnerships for competitive advantage is receiving considerable recognition among both academic researchers and industry executives. Trust is an essential factor for a company to collaborate with its partner through supply chain (SC). In this paper we analyze the factors of trust relationship in green supply chain (GSC). A conceptual model of determinants of trust in GSC is presented. Finally, research propositions are discussed.展开更多
This work, through an empirical research (Jayaram, Kannan and Tan model), aims at analysing, at the same time, the effect of "structural mechanisms" and "relationships building" factors on the value creation pro...This work, through an empirical research (Jayaram, Kannan and Tan model), aims at analysing, at the same time, the effect of "structural mechanisms" and "relationships building" factors on the value creation process in the Supply Chain. The two factors have been chosen among others, as they have been considered able to improve the internal and external processes of the firm and the Supply Chain, and in consequence, able to influence the value creation process of the Supply Chain Management. The research has been directed to the chemical and pharmaceutical sector of the Southern Lazio (Italy) and a factorial analysis, using the software SPSS (16.0) which has been performed in order to verify the influence of these factors in value creation process of the Supply Chain The outcomes confirm the positive contribute in the value creation process for companies that take care of the relationships among the stakeholders in the management process of the supply chain (the "relationships building" factor) and, in parallel with the analysis of the same process, the secondary role of the "structural mechanisms" factor has been highlighted.展开更多
To the accomplishment of this article, we have chosen, as a case study, a small Goiana construction company that acted in the market of social housing. The main goal of this work is to analyze the fundamental aspects ...To the accomplishment of this article, we have chosen, as a case study, a small Goiana construction company that acted in the market of social housing. The main goal of this work is to analyze the fundamental aspects related to the management of the flow of supplies in civil construction to achieve a greater streamlining of logistic processes involved in supplying material. A checklist was developed for the purpose of data collection, and it was applied by means of an interview with the person in charge of the purchase department of the enterprise. In addition, this person is the engineer of the site. Taking into account the exploratory feature of this research, the construction site was visited so that some issues, such as quality aspects, losses, cleanliness and organization, could be observed. This on-site data collection visit was carried out through visual analyses and photographs. The obtained results were subdivided into a quantitative and a qualitative analysis. In this way, it was possible to see that the production process still has many phases to be improved. What is more, it was possible to see that the construction company knows its flaws and necessities to improve its processes although the final result does not have the expected quality. Being aware of this need for improvement, the construction company aims at having an affordable price product to the target public, especially when it is associated to an image that shows quality.展开更多
With expanding environmental and climate change regulatory frameworks, </span><span style="font-family:Verdana;">the fossil</span></span><span style="font-family:Verdana;"...With expanding environmental and climate change regulatory frameworks, </span><span style="font-family:Verdana;">the fossil</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">based baseload</span><span style="font-family:""> <span style="font-family:Verdana;">generation is forced to decline</span><span style="font-family:Verdana;">, thus making room for more and more generation based on renewable and other carbon-free energy sources. This paper deals with a number of controversial issues and open questions concerning </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">growing penetration of renewable energy sources into power generation systems, often without due care of the impacts of variable as compared to conventional generation on </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">reliability of electricity supply. Particular attention is paid to baseload generation, power market design, system operation under extreme weather conditions, energy storage, back-up</span><span style="font-family:Verdana;">,</span><span style="font-family:""><span style="font-family:Verdana;"> and reserve power, as well as to the role of mechanical inertia an</span><span style="font-family:Verdana;">d reliability of on-site fuel supply, demonstrated on an example of coal </span><span style="font-family:Verdana;">excavation and delivery to a power plant.展开更多
Renewable energy sources(RESs)are considered to be reliable and green electric power generation sources.Photovoltaics(PVs)and wind turbines(WTs)are used to provide electricity in remote areas.Optimal sizing of hybrid ...Renewable energy sources(RESs)are considered to be reliable and green electric power generation sources.Photovoltaics(PVs)and wind turbines(WTs)are used to provide electricity in remote areas.Optimal sizing of hybrid RESs is a vital challenge in a stand-alone environment.The meta-heuristic algorithms proposed in the past are dependent on algorithm-specific parameters for achieving an optimal solution.This paper proposes a hybrid algorithm of Jaya and a teaching–learning-based optimization(TLBO)named the JLBO algorithm for the optimal unit sizing of a PV–WT–battery hybrid system to satisfy the consumer’s load at minimal total annual cost(TAC).The reliability of the system is considered by a maximum allowable loss of power supply probability(LPSPmax)concept.The results obtained from the JLBO algorithm are compared with the original Jaya,TLBO,and genetic algorithms.The JLBO results show superior performance in terms of TAC,and the PV–WT–battery hybrid system is found to be the most economical scenario.This system provides a cost-effective solution for all proposed LPSPmax values as compared with PV–battery and WT–battery systems.展开更多
Increasing railway traffic and energy utilization issues prompt electrified railway systems to be more economical,efficient and sustainable.As regenerative braking energy in railway systems has huge potential for opti...Increasing railway traffic and energy utilization issues prompt electrified railway systems to be more economical,efficient and sustainable.As regenerative braking energy in railway systems has huge potential for optimized utilization,a lot of research has been focusing on how to use the energy efficiently and gain sustainable benefits.The energy storage system is an alternative because it not only deals with regenerative braking energy but also smooths drastic fluctuation of load power profile and optimizes energy management.In this work,we propose a co-phase traction power supply system with super capacitor(CSS_SC)for the purpose of realizing the function of energy management and power quality management in electrified railways.Besides,the coordinated control strategy is presented to match four working modes,including traction,regenerative braking,peak shaving and valley filling.A corresponding simulation model is built in MATLAB/Simulink to verify the feasibility of the proposed system under dynamic working conditions.The results demonstrate that CSS_SC is flexible to deal with four different working conditions and can realize energy saving within the allowable voltage unbalance of 0.008%in simulation in contrast to 1.3%of the standard limit.With such a control strategy,the performance of super capacitor is controlled to comply with efficiency and safety constraints.Finally,a case study demonstrates the improvement in power fluctuation with the valley-to-peak ratio reduced by 20.3%and the daily load factor increased by 17.9%.展开更多
Effective storage of healthcare information is the foundation of the rapid development of electronic health recorder (EHR). This paper presents a research on the data model of EHR storage, focusing on solving the co...Effective storage of healthcare information is the foundation of the rapid development of electronic health recorder (EHR). This paper presents a research on the data model of EHR storage, focusing on solving the complex and abstract information model and data types in HL7 V3(Health Level 7 Version 3.0) as well as HL7 localizing storage. Using health-care information exchange and sharing standards may settle the problem of interoperability between heterogeneous systems. HL7 is the most widely accepted and used standard. HL7 standardizes the information format in the process of transmission. Nevertheless, it can not guide the storage of health-care data directly. HL7 V3 developed an abstract information model-reference information model (RIM) and data types in it are complex. In this paper, we propose an approach on converting from the abstract HL7 V3 information model to the relational data model. Our approach resolves RIM's complex relationships and its data types and localizes the HL7 V3.展开更多
This paper presents a computational method to model and evaluate if Pumped Storage Plants (PSP) have the potential to reduce the intermittency of wind generation from different sites in Brazil and to improve the opera...This paper presents a computational method to model and evaluate if Pumped Storage Plants (PSP) have the potential to reduce the intermittency of wind generation from different sites in Brazil and to improve the operation efficiency of hydroelectric plants when operating in cascade. Since the problem to be solved does not have a defined analytic solution, a Stochastic Optimization Algorithm was implemented to reach an optimal solution to the set of equations, inputs and proposed scenarios. A case study was developed based on the Paraná River Basin and the results shows that the model can operate in a variety of different operational patterns, making feasible the evaluation of different hydrological and wind scenarios. Given the Model support, it is easy to assume different PSP storage and generation capacities, allowing the comparison between the efficiency improvement of a conventional Pumped-Storage and a Season-al-Pumped-Storage in the same scenario. The study concludes that a PSP can effectively reduce the intermittency of wind and solar sources and contribute to the optimization of the Brazilian electricity sector.展开更多
As firms come under greater market pressure, the management of the inter-functional design/manufacture relationship becomes a more important competitive variable. The characteristics of the design-manufacture interfac...As firms come under greater market pressure, the management of the inter-functional design/manufacture relationship becomes a more important competitive variable. The characteristics of the design-manufacture interface were analyzed, and several methods of the design-manufacture interface relationship management were compared. Based on theories concerned and enterprise practice, how to manage the relationship of design-manufacture interface to reduce the product cost and shorten the time-to-market was demonstrated, finally the competitive advantage was improved.展开更多
Spiritual demand as one of the basic requirements of human, has more important significance for the elderly group. Descriptive statistic analysis shows that in the CLHLS, the elderly spiritual demand and supply is in ...Spiritual demand as one of the basic requirements of human, has more important significance for the elderly group. Descriptive statistic analysis shows that in the CLHLS, the elderly spiritual demand and supply is in a state of disequilibrium in our country, supply is far less than demand. The main factors of restricting the old people's spiritual need are not being met, including economic factors, intergenerational relations factors, emotional factors and the particularity of spiritual demand, etc. So we need to change our ideas, with the demand of the old structure and strength, by constructing a complete supply system of family, society and government to strengthen for the supply of the spiritual needs of old people, so that the elderly would be happy during his or her later lives.展开更多
基金Supported by Project of Science and Technology of PetroChina (2021DJ17,2021DJ21)。
文摘As a kind of clean energy which creates little carbon dioxide, natural gas will play a key role in the process of achieving “Peak Carbon Dioxide Emission” and “Carbon Neutrality”. The Long-range Energy Alternatives Planning System(LEAP) model was improved by using new parameters including comprehensive energy efficiency and terminal effective energy consumption. The Back Propagation(BP) Neural Network–LEAP model was proposed to predict key data such as total primary energy consumption, energy mix, carbon emissions from energy consumption, and natural gas consumption in China. Moreover, natural gas production in China was forecasted by the production composition method. Finally, based on the forecast results of natural gas supply and demand, suggestions were put forward on the development of China’s natural gas industry under the background of “Dual Carbon Targets”. The research results indicate that under the background of carbon peak and carbon neutrality, China’s primary energy consumption will peak(59.4×10^(8)tce) around 2035, carbon emissions from energy consumption will peak(103.4×10^(8)t) by 2025, and natural gas consumption will peak(6100×10^(8)m^(3)) around 2040, of which the largest increase will be contributed by the power sector and industrial sector. China’s peak natural gas production is about(2800–3400)×10^(8)m^(3), including(2100–2300)×10^(8)m^(3)conventional gas(including tight gas),(600–1050)×10^(8)m^(3)shale gas, and(150–220)×10^(8)m^(3)coalbed methane. Under the background of carbon peak and carbon neutrality, the natural gas consumption and production of China will further increase, showing a great potential of the natural gas industry.
基金support from the U.S.Department of the Army and U.S.Army Future Commandsupport from the U.S.Army Research Laboratory Senior Research Fellowship Program。
文摘The oxygen evolution reaction(OER)is the essential module in energy conversion and storage devices such as electrolyzer,rechargeable metal–air batteries and regenerative fuel cells.The adsorption energy scaling relations between the reaction intermediates,however,impose a large intrinsic overpotential and sluggish reaction kinetics on OER catalysts.Developing advanced electrocatalysts with high activity and stability based on non-noble metal materials is still a grand challenge.Central to the rational design of novel and high-efficiency catalysts is the development and understanding of quantitative structure–activity relationships,which correlate the catalytic activities with structural and electronic descriptors.This paper comprehensively reviews the benchmark descriptors for OER electrolysis,aiming to give an in-depth understanding on the origins of the electrocatalytic activity of the OER and further contribute to building the theory of electrocatalysis.Meanwhile,the cutting-edge research frontiers for proposing new OER paradigms and crucial strategies to circumvent the scaling relationship are also summarized.Challenges,opportunities and perspectives are discussed,intending to shed some light on the rational design concepts and advance the development of more efficient catalysts for enhancing OER performance.
文摘This paper reviews literature on the relationship between food supply and obesity. The focus is on the supply, cost, and variety of food through various types of food outlets and the impact of these factors on obesity in developed countries. The article reveals complex relationships between food supply factors and obesity. A numer of factors related to lifestyles including the mobility of populations and the use of motor vehicles greatly reduce the impact of the local environment on family and individual eating patterns. However, obesity is also affected by factors such as the type and density of food outlets, the cost of food, the travel distance and means of transport to the food outlet. While the relationship between food supply and obesity in the literature reveals complex and mixed findings, this paper concludes obesity is complex and food supply is only part of this phenomenon’s predictors. Because the relationship between food supply and obesity is mediated by such multiple and complex factors including population behaviours, beliefs, lifestyles, knowledge and both food and physical environments;multiple strategies including policy development and other strategies aimed at manipulating food environments, physical environments, populations’ beliefs, behaviours and practices must be considered in searching for evidence to effectively combat obesity.
基金co-supported by the National Basic Research Program of China(Grant No.2011CB201103)the National Science and Technology Major Project(Grant No.2011ZX05004003)
文摘Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin,which is taken as a study case in this paper.It is still not clear how the secondary storage space shape influences the P-& S-wave velocities (or elastic properties) in complex carbonate reservoirs.In this paper,three classical rock physics models (Wyllie timeaverage equation,Gassmann equation and the Kuster-Toks z model) are comparably analyzed for their construction principles and actual velocity prediction results,aiming at determining the most favourable rock physics model to consider the influence of secondary storage space shape.Then relationships between the P-& S-wave velocities in carbonate reservoirs and geometric shapes of secondary storage spaces are discussed from different aspects based on actual well data by employing the favourable rock physics model.To explain the influence of secondary storage space shape on V P-V S relationship,it is analyzed for the differences of S-wave velocities between derived from common empirical relationships (including Castagna's mud rock line and Greenberg-Castagna V P-V S relationship) and predicted by the rock physics model.We advocate that V P-V S relationship for complex carbonate reservoirs should be built for different storage space types.For the carbonate reservoirs in the Tarim Basin,the V P-V S relationships for fractured,fractured-cavernous,and fractured-hole-vuggy reservoirs are respectively built on the basis of velocity prediction and secondary storage space type determination.Through the discussion above,it is expected that the velocity prediction and the V P-V S relationships for complex carbonate reservoirs should fully consider the influence of secondary storage space shape,thus providing more reasonable constraints for prestack inversion,further building a foundation for realizing carbonate reservoir prediction and fluid prediction.
基金supported by Science and Technology Project of SGCC(5108-202218280A-2-375-XG)。
文摘In response to the underutilization of energy and insufficient flexible operation capability of rural energy supply systems in China,this study proposes an optimal dispatch approach for a rural multi-energy supply system(RMESS)considering virtual energy storage(VES).First,to enable the flexible utilization of rural biomass resources and the thermal inertia of residential building envelopes,this study constructed VES-I and VES-II models that describe electrical-thermal and electrical-gas coupling from an electrical viewpoint.Subsequently,an RMESS model encompassing these two types of VES was formulated.This model delineates the intricate interplay of multi-energy components within the RMESS framework and facilitates the precise assessment of the adjustable potential for optimizing RMESS operations.Based on the above models,a day-ahead optimal dispatch model for an RMESS considering a VES is proposed to achieve optimal economic performance while ensuring efficient energy allocation.Comparative simulations validated the effectiveness of the VES modeling and the day-ahead optimal dispatch approach for the RMESS.
基金Supported by the National Natural Science Foundation(71303040)Chinese Postdoctoral Science Foundation 54 Group of First Aid(2013M540268)the Fund Project of Humanities and Social Science of Youth in Research of the Ministry of Education(13YJC790142)
文摘Dairy industry is the pillar of Heilongjiang Province. The contractual relationship of the dairy supply chain played a vital role in the dairy industry for development. The contractual relationship between the main dairy farming body and the dairy processing enterprise, as well as the impact of this contractual relationship on their cooperation in dairy supply chain were studied. Taking 366 dairy farming bodies in Heilongjiang Province as the main research objects, Likert scale was used to measure the factors affecting the contractual relationship and applied these factors to the correlation construction of dairy farming body and processing enterprise. Then, confirmatory factor analysis was used to collect data and made the conclusion that once dairy farming body perceived the opportunistic behavior and lacking of cooperation, the trust of dairy processing enterprise would be lost. Additionally, the satisfaction of dairy farming body on partnership also had a positive effect on the level of trust and commitment, the relative dependence and the perception of the partnerships, which made it possible to analyze how to strengthen the contractual relationship and provide theoretical basis for dairy industry development in Heilongjiang Province.
基金supported in part by National Natural Science Foundation of China under Grant Nos.72171169 and 71971076.
文摘This paper examines the optimal forecast-sharing strategy in a hybrid-format online platform supply chain where a supplier sells a product through agency format and reselling format provided by a platform retailer who possesses demand forecasts from two channels.Forecast asymmetry and co-opetitive relationship arise between the platform retailer and the supplier,which affect their operational decisions and the supply chain’s performance.To improve supply chain efficiency,we compare different forecast-sharing strategies(i.e.,no forecast sharing,sharing a single forecast,and sharing two forecasts),and analyze the effects of co-opetitive parameters on the optimal forecast-sharing strategy.Our analysis shows that forecast sharing is always beneficial to the supplier,and sharing two forecasts is more beneficial than sharing a single forecast.Whereas for the platform retailer and the whole supply chain,forecast sharing is beneficial only under certain conditions,depending on the co-opetitive parameters.The optimal forecast-sharing strategy is the result of a combination of the negative effect of double marginalization in reselling channel and the positive effect of responding pricing to demand uncertainty in agency channel.We illustrate the parameter regions of the platform retailer’s voluntary sharing,contract sharing,and no sharing,and also find that higher channel competition intensity,higher market share of agency channel,and higher commission rate can promote the platform retailer’s voluntary sharing.Our study extends the research scope of demand forecast-sharing and sheds light on the decision-making processes for managing a hybrid-format online platform supply chain.
文摘In this study,the present situation and characteristics of power supply in remote areas are summarized.By studying the cases of power supply projects in remote areas,the experience is analyzed and described,and the applicability of related technologies,such as grid-forming storage and power load management,is studied,including grid-connection technologies,such as grid-forming converters and power load management.On this basis,three power-supply modes were proposed.The application scenarios and advantages of the three modes were compared and analyzed.Based on the local development situation,the temporal sequences of the three schemes are described,and a case study was conducted.The study of the heavy-load power supply mode in remote areas contributes to solving the problem of heavy-load green power consumption in remote areas and promoting the further development of renewable energy.
基金supported by the National Natural Science Foundation of China(52202327)Science and Technology Commission of Shanghai Municipality(22ZR1471300)the Key Research Program of Frontier Science,Chinese Academy of Sciences(Grant No.QYZDJ-SSW-JSC013 and KGZD-EW-T06).
文摘Crystal structure determines electrochemical energy storage characteristics;this is the underlying logic of material design.To date,hundreds of electrode materials have been developed to pursue superior performance.However,it remains a great challenge to understand the fundamental structure–performance relationship and achieve quantitative crystal structure design for efficient energy storage.In this review,we introduce the concept of crystal packing factor(PF),which can quantify crystal packing density.We then present and classify the typical crystal structures of attractive cathode/anode materials.Comparative PF analyses of different materials,including polymorphs,isomorphs,and others,are performed to clarify the influence of crystal packing density on energy storage performance through electronic and ionic conductivities.Notably,the practical electronic/ionic conductivities of energy storage materials are based on their intrinsic characteristics related to the PF yet are also affected by extrinsic factors.The PF provides a novel avenue for understanding the electrochemical performance of pristine materials and may offer guidance on designing better materials.Additional approaches involve size regulation,doping,carbon additives,and other methods.We also propose extended PF concepts to understand charge storage and transport behavior at different scales.Finally,we provide our insights on the major challenges and prospective solutions in this highly exciting field.
文摘Caspian Gas into Balkans over medium to long term becames Albanian case on June 2013 when TAP route was selected. After Albanian National Territory Council approved TAP AG's Compound Development Permit, the project should start Construction Phase 1. Existing gas pipeline connections of Albania within the European network via TAP, is highly estimated by energy authorities in both technical and regulating aspects. New pipelines are projected to be build in order to meet local energy consume and seasonal fluctuations, as well as needs of Kosovo and FYROM. Some of important points: determination on the capacity sector building for a due Albanian Gas Market Model, supply options on the future gasification, alternatives of opening underground gas storages in the salt domes of Dumre region and extending pipelines to neighboring countries. By assistance of the Secretariat of Energy Community, MEI starts drafting the new gas law to meet Third Energy Package. TAP project, IAP project, Albania-Kosovo Pipeline, an LNG plant and terminals coastal construction, can contribute on the diversification of gas supply. Underground Gas Storage potentials are geologic solution target, considering the Upper Miocene depleted sandstone gas fields of Divjaka, as well as the Dumre evaporitic deposits diapir of the Upper Triassic.
文摘Managing supply chain partnerships for competitive advantage is receiving considerable recognition among both academic researchers and industry executives. Trust is an essential factor for a company to collaborate with its partner through supply chain (SC). In this paper we analyze the factors of trust relationship in green supply chain (GSC). A conceptual model of determinants of trust in GSC is presented. Finally, research propositions are discussed.
文摘This work, through an empirical research (Jayaram, Kannan and Tan model), aims at analysing, at the same time, the effect of "structural mechanisms" and "relationships building" factors on the value creation process in the Supply Chain. The two factors have been chosen among others, as they have been considered able to improve the internal and external processes of the firm and the Supply Chain, and in consequence, able to influence the value creation process of the Supply Chain Management. The research has been directed to the chemical and pharmaceutical sector of the Southern Lazio (Italy) and a factorial analysis, using the software SPSS (16.0) which has been performed in order to verify the influence of these factors in value creation process of the Supply Chain The outcomes confirm the positive contribute in the value creation process for companies that take care of the relationships among the stakeholders in the management process of the supply chain (the "relationships building" factor) and, in parallel with the analysis of the same process, the secondary role of the "structural mechanisms" factor has been highlighted.
文摘To the accomplishment of this article, we have chosen, as a case study, a small Goiana construction company that acted in the market of social housing. The main goal of this work is to analyze the fundamental aspects related to the management of the flow of supplies in civil construction to achieve a greater streamlining of logistic processes involved in supplying material. A checklist was developed for the purpose of data collection, and it was applied by means of an interview with the person in charge of the purchase department of the enterprise. In addition, this person is the engineer of the site. Taking into account the exploratory feature of this research, the construction site was visited so that some issues, such as quality aspects, losses, cleanliness and organization, could be observed. This on-site data collection visit was carried out through visual analyses and photographs. The obtained results were subdivided into a quantitative and a qualitative analysis. In this way, it was possible to see that the production process still has many phases to be improved. What is more, it was possible to see that the construction company knows its flaws and necessities to improve its processes although the final result does not have the expected quality. Being aware of this need for improvement, the construction company aims at having an affordable price product to the target public, especially when it is associated to an image that shows quality.
文摘With expanding environmental and climate change regulatory frameworks, </span><span style="font-family:Verdana;">the fossil</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">based baseload</span><span style="font-family:""> <span style="font-family:Verdana;">generation is forced to decline</span><span style="font-family:Verdana;">, thus making room for more and more generation based on renewable and other carbon-free energy sources. This paper deals with a number of controversial issues and open questions concerning </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">growing penetration of renewable energy sources into power generation systems, often without due care of the impacts of variable as compared to conventional generation on </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">reliability of electricity supply. Particular attention is paid to baseload generation, power market design, system operation under extreme weather conditions, energy storage, back-up</span><span style="font-family:Verdana;">,</span><span style="font-family:""><span style="font-family:Verdana;"> and reserve power, as well as to the role of mechanical inertia an</span><span style="font-family:Verdana;">d reliability of on-site fuel supply, demonstrated on an example of coal </span><span style="font-family:Verdana;">excavation and delivery to a power plant.
文摘Renewable energy sources(RESs)are considered to be reliable and green electric power generation sources.Photovoltaics(PVs)and wind turbines(WTs)are used to provide electricity in remote areas.Optimal sizing of hybrid RESs is a vital challenge in a stand-alone environment.The meta-heuristic algorithms proposed in the past are dependent on algorithm-specific parameters for achieving an optimal solution.This paper proposes a hybrid algorithm of Jaya and a teaching–learning-based optimization(TLBO)named the JLBO algorithm for the optimal unit sizing of a PV–WT–battery hybrid system to satisfy the consumer’s load at minimal total annual cost(TAC).The reliability of the system is considered by a maximum allowable loss of power supply probability(LPSPmax)concept.The results obtained from the JLBO algorithm are compared with the original Jaya,TLBO,and genetic algorithms.The JLBO results show superior performance in terms of TAC,and the PV–WT–battery hybrid system is found to be the most economical scenario.This system provides a cost-effective solution for all proposed LPSPmax values as compared with PV–battery and WT–battery systems.
文摘Increasing railway traffic and energy utilization issues prompt electrified railway systems to be more economical,efficient and sustainable.As regenerative braking energy in railway systems has huge potential for optimized utilization,a lot of research has been focusing on how to use the energy efficiently and gain sustainable benefits.The energy storage system is an alternative because it not only deals with regenerative braking energy but also smooths drastic fluctuation of load power profile and optimizes energy management.In this work,we propose a co-phase traction power supply system with super capacitor(CSS_SC)for the purpose of realizing the function of energy management and power quality management in electrified railways.Besides,the coordinated control strategy is presented to match four working modes,including traction,regenerative braking,peak shaving and valley filling.A corresponding simulation model is built in MATLAB/Simulink to verify the feasibility of the proposed system under dynamic working conditions.The results demonstrate that CSS_SC is flexible to deal with four different working conditions and can realize energy saving within the allowable voltage unbalance of 0.008%in simulation in contrast to 1.3%of the standard limit.With such a control strategy,the performance of super capacitor is controlled to comply with efficiency and safety constraints.Finally,a case study demonstrates the improvement in power fluctuation with the valley-to-peak ratio reduced by 20.3%and the daily load factor increased by 17.9%.
基金supported by Dongguan City Medical and Health Research Project under Grant No. 200910515018Guangdong Provincial Department Cooperation Project under Grant No. 2009B090300362+1 种基金Sichuan Province Science & Technology Pillar Program under Grant No.2010SZ0062the Fundamental Research Funds for the Central Universities under Grant No. ZYGX2009X016
文摘Effective storage of healthcare information is the foundation of the rapid development of electronic health recorder (EHR). This paper presents a research on the data model of EHR storage, focusing on solving the complex and abstract information model and data types in HL7 V3(Health Level 7 Version 3.0) as well as HL7 localizing storage. Using health-care information exchange and sharing standards may settle the problem of interoperability between heterogeneous systems. HL7 is the most widely accepted and used standard. HL7 standardizes the information format in the process of transmission. Nevertheless, it can not guide the storage of health-care data directly. HL7 V3 developed an abstract information model-reference information model (RIM) and data types in it are complex. In this paper, we propose an approach on converting from the abstract HL7 V3 information model to the relational data model. Our approach resolves RIM's complex relationships and its data types and localizes the HL7 V3.
文摘This paper presents a computational method to model and evaluate if Pumped Storage Plants (PSP) have the potential to reduce the intermittency of wind generation from different sites in Brazil and to improve the operation efficiency of hydroelectric plants when operating in cascade. Since the problem to be solved does not have a defined analytic solution, a Stochastic Optimization Algorithm was implemented to reach an optimal solution to the set of equations, inputs and proposed scenarios. A case study was developed based on the Paraná River Basin and the results shows that the model can operate in a variety of different operational patterns, making feasible the evaluation of different hydrological and wind scenarios. Given the Model support, it is easy to assume different PSP storage and generation capacities, allowing the comparison between the efficiency improvement of a conventional Pumped-Storage and a Season-al-Pumped-Storage in the same scenario. The study concludes that a PSP can effectively reduce the intermittency of wind and solar sources and contribute to the optimization of the Brazilian electricity sector.
文摘As firms come under greater market pressure, the management of the inter-functional design/manufacture relationship becomes a more important competitive variable. The characteristics of the design-manufacture interface were analyzed, and several methods of the design-manufacture interface relationship management were compared. Based on theories concerned and enterprise practice, how to manage the relationship of design-manufacture interface to reduce the product cost and shorten the time-to-market was demonstrated, finally the competitive advantage was improved.
文摘Spiritual demand as one of the basic requirements of human, has more important significance for the elderly group. Descriptive statistic analysis shows that in the CLHLS, the elderly spiritual demand and supply is in a state of disequilibrium in our country, supply is far less than demand. The main factors of restricting the old people's spiritual need are not being met, including economic factors, intergenerational relations factors, emotional factors and the particularity of spiritual demand, etc. So we need to change our ideas, with the demand of the old structure and strength, by constructing a complete supply system of family, society and government to strengthen for the supply of the spiritual needs of old people, so that the elderly would be happy during his or her later lives.