A drag prediction method based on thrust drag bookkeeping(TDB) is introduced for civil jet propulsion/airframe integration performance analysis.The method is derived from the control volume theory of a powered-on na...A drag prediction method based on thrust drag bookkeeping(TDB) is introduced for civil jet propulsion/airframe integration performance analysis.The method is derived from the control volume theory of a powered-on nacelle.Key problem of the TDB is identified to be accurate prediction of velocity coefficient of the powered-on nacelle.Accuracy of CFD solver is validated by test cases of the first AIAA Propulsion Aerodynamics Workshop.Then the TDB method is applied to thrust and drag decomposing of a realistic aircraft.A linear relation between the computations assumed free stream Mach number and the velocity coefficient result is revealed.The thrust losses caused by nozzle internal drag and pylon scrubbing are obtained by the isolated nacelle and mapped on to the in-flight whole configuration analysis.Effects of the powered-on condition are investigated by comparing through-flow configuration with powered-on configuration.The variance on aerodynamic coefficients and pressure distribution is numerically studied.展开更多
Scientific assessment of the accounting over carbon in the terrestrial ecosystem in the process land use/land cover changes caused by human activities will help reduce the uncertainty in estimating carbon emissions fr...Scientific assessment of the accounting over carbon in the terrestrial ecosystem in the process land use/land cover changes caused by human activities will help reduce the uncertainty in estimating carbon emissions from the terrestrial ecosystem. This study employs a bookkeeping model to estimate the carbon emissions from farmland reclamation in China during the past 300 years based on the annual rate of land use changes(derived from historical natural vegetation, farmland data), preset carbon density and coefficients of disturbance curves. We find out that:(1) there was a net increase of 79.30×10~4km^2 in national farmland; about 65% of reclaimed farmland had been forest land and 26% of that had been grass land previously;(2) the total amount of carbon emissions from farmland expansion in China had been between 2.94 and 5.61 Pg with the median 3.78 Pg during the past 300 years; specifically, carbon emissions of vegetation were 1.58 Pg while those of soil ranged from 1.35 Pg to4.03 Pg with the median 2.20 Pg;(3) carbon emissions vary greatly across various ecosystems: the emissions were most from forest land, and then grass land and swamps, and the least from shrubs; deserts functioned more likely to be carbon stock in the process of land reclamation;(4) along the time line, carbon emissions had decreased first and then increased while the peak emissions occurred in the first half of 20 th century; and spatially, carbon emissions were most released in Northeast and Southwest China; Northwest China was of the minimum carbon emissions.展开更多
消费的增长以量变带动质变,消费结构的升级势在必行。结合大学生消费行为的现状,在记账APP模式中创新性提出大数据与"心愿清单"相结合的方式,对智能消费记账APP进行可行性研究,并且利用相关技术初步设计了消费控制类的记账APP...消费的增长以量变带动质变,消费结构的升级势在必行。结合大学生消费行为的现状,在记账APP模式中创新性提出大数据与"心愿清单"相结合的方式,对智能消费记账APP进行可行性研究,并且利用相关技术初步设计了消费控制类的记账APP—"RCU"(rational consumption in universities)。基于Android平台并结合visual studio和unity软件进行APP技术开发设计,包括系统分开发相关技术和系统总体设计部分,推动APP在实际场景的应用。展开更多
Corporate sustainability reporting has become increasingly important in recent years.However,conventional approaches reach their limits when it comes to quantifying and measuring the actual sustainability performance ...Corporate sustainability reporting has become increasingly important in recent years.However,conventional approaches reach their limits when it comes to quantifying and measuring the actual sustainability performance of a company.This article presents a new approach:Sustainable Performance Accounting(SPA),which is based on an extension of bookkeeping by including ESG bookkeeping.SPA enables companies to systematically measure and manage their sustainability performance.The article provides an overview of the basics of SPA methodology and uses a comprehensive example showing how SPA can be implemented in practice.The article is aimed at interested readers from science and practice as well as decision-makers who are interested in future-oriented sustainability reporting.展开更多
Normal practice of financial management in the defense system is crucial for the performance of assigned tasks. Payment transactions in cash, in addition to non-cash payment system are very important if we take into a...Normal practice of financial management in the defense system is crucial for the performance of assigned tasks. Payment transactions in cash, in addition to non-cash payment system are very important if we take into account the specificity of the defense system. With limited financial resources optimization level of bookkeeping cash limit should provide continuous funding of units and institutions of the defense system. The aim of this paper is to show that using the method of analytic hierarchy process (AHP) we can help optimize the allocation of cash financial funds within the defense system.展开更多
Since 1865, the scholars from different countries have been studying the Genoese Massari's ledger of 1340. The authors have used a fundamentally new approach when studying this famous register. The authors have also ...Since 1865, the scholars from different countries have been studying the Genoese Massari's ledger of 1340. The authors have used a fundamentally new approach when studying this famous register. The authors have also analyzed the full-scale financial processes (from registering the expenses of the commune to their coverage by revenue) instead of analyzing some separate transactions which could prove the presence of the double-entry when registering each economic fact. This becomes possible as a result of the reconstruction of medieval entries and registers in the form of a modem account and the construction of the computer model of the whole ledger of 1340. The model of the system is formed according to seven summits of the revenue of the commune, which are distributed upon many factors of registered expenses and united into 17 reporting points. The special attention is paid to the date of the transaction. The authors have found many answers to some questions which were mysteries before. The explanation is given to the sales of goods below the purchasing price and to the exchange of money with significant losses.展开更多
基金supported by the National Key Basic Research Program of China (No.2014CB744801)the National Natural Science Foundation of China (Nos.11102098 and 11372160)the Aeronautical Science Foundation of China (No.2013ZA58002)
文摘A drag prediction method based on thrust drag bookkeeping(TDB) is introduced for civil jet propulsion/airframe integration performance analysis.The method is derived from the control volume theory of a powered-on nacelle.Key problem of the TDB is identified to be accurate prediction of velocity coefficient of the powered-on nacelle.Accuracy of CFD solver is validated by test cases of the first AIAA Propulsion Aerodynamics Workshop.Then the TDB method is applied to thrust and drag decomposing of a realistic aircraft.A linear relation between the computations assumed free stream Mach number and the velocity coefficient result is revealed.The thrust losses caused by nozzle internal drag and pylon scrubbing are obtained by the isolated nacelle and mapped on to the in-flight whole configuration analysis.Effects of the powered-on condition are investigated by comparing through-flow configuration with powered-on configuration.The variance on aerodynamic coefficients and pressure distribution is numerically studied.
基金supported by the National Natural Science Foundation of China (Grant No. 41671082)
文摘Scientific assessment of the accounting over carbon in the terrestrial ecosystem in the process land use/land cover changes caused by human activities will help reduce the uncertainty in estimating carbon emissions from the terrestrial ecosystem. This study employs a bookkeeping model to estimate the carbon emissions from farmland reclamation in China during the past 300 years based on the annual rate of land use changes(derived from historical natural vegetation, farmland data), preset carbon density and coefficients of disturbance curves. We find out that:(1) there was a net increase of 79.30×10~4km^2 in national farmland; about 65% of reclaimed farmland had been forest land and 26% of that had been grass land previously;(2) the total amount of carbon emissions from farmland expansion in China had been between 2.94 and 5.61 Pg with the median 3.78 Pg during the past 300 years; specifically, carbon emissions of vegetation were 1.58 Pg while those of soil ranged from 1.35 Pg to4.03 Pg with the median 2.20 Pg;(3) carbon emissions vary greatly across various ecosystems: the emissions were most from forest land, and then grass land and swamps, and the least from shrubs; deserts functioned more likely to be carbon stock in the process of land reclamation;(4) along the time line, carbon emissions had decreased first and then increased while the peak emissions occurred in the first half of 20 th century; and spatially, carbon emissions were most released in Northeast and Southwest China; Northwest China was of the minimum carbon emissions.
文摘消费的增长以量变带动质变,消费结构的升级势在必行。结合大学生消费行为的现状,在记账APP模式中创新性提出大数据与"心愿清单"相结合的方式,对智能消费记账APP进行可行性研究,并且利用相关技术初步设计了消费控制类的记账APP—"RCU"(rational consumption in universities)。基于Android平台并结合visual studio和unity软件进行APP技术开发设计,包括系统分开发相关技术和系统总体设计部分,推动APP在实际场景的应用。
文摘Corporate sustainability reporting has become increasingly important in recent years.However,conventional approaches reach their limits when it comes to quantifying and measuring the actual sustainability performance of a company.This article presents a new approach:Sustainable Performance Accounting(SPA),which is based on an extension of bookkeeping by including ESG bookkeeping.SPA enables companies to systematically measure and manage their sustainability performance.The article provides an overview of the basics of SPA methodology and uses a comprehensive example showing how SPA can be implemented in practice.The article is aimed at interested readers from science and practice as well as decision-makers who are interested in future-oriented sustainability reporting.
文摘Normal practice of financial management in the defense system is crucial for the performance of assigned tasks. Payment transactions in cash, in addition to non-cash payment system are very important if we take into account the specificity of the defense system. With limited financial resources optimization level of bookkeeping cash limit should provide continuous funding of units and institutions of the defense system. The aim of this paper is to show that using the method of analytic hierarchy process (AHP) we can help optimize the allocation of cash financial funds within the defense system.
文摘Since 1865, the scholars from different countries have been studying the Genoese Massari's ledger of 1340. The authors have used a fundamentally new approach when studying this famous register. The authors have also analyzed the full-scale financial processes (from registering the expenses of the commune to their coverage by revenue) instead of analyzing some separate transactions which could prove the presence of the double-entry when registering each economic fact. This becomes possible as a result of the reconstruction of medieval entries and registers in the form of a modem account and the construction of the computer model of the whole ledger of 1340. The model of the system is formed according to seven summits of the revenue of the commune, which are distributed upon many factors of registered expenses and united into 17 reporting points. The special attention is paid to the date of the transaction. The authors have found many answers to some questions which were mysteries before. The explanation is given to the sales of goods below the purchasing price and to the exchange of money with significant losses.