分析了现代军工领域虚拟试验的特性和需求,提出了现代军工领域虚拟试验支撑环境急需解决的问题和研究内容;高级体系结构(High Level Architecture,HLA)、试验与训练使能体系结构(The Test and Training Enabling Architecture,TENA)、...分析了现代军工领域虚拟试验的特性和需求,提出了现代军工领域虚拟试验支撑环境急需解决的问题和研究内容;高级体系结构(High Level Architecture,HLA)、试验与训练使能体系结构(The Test and Training Enabling Architecture,TENA)、虚拟试验床(Virtual Test Bed,VTB)等技术是国外仿真和试验领域比较成熟的研究成果,对我国军工领域虚拟试验支撑环境的研究具有很大的借鉴意义,文中从分布虚拟试验系统的开发、模型集成、系统运行及资源管理等角度分析了HLA、TENA、VTB等的相关技术和研究现状,对我国研究分布虚拟试验的理论和关键技术具有一定的参考价值。展开更多
Superlubricity refers to a sliding regime in which contacting surfaces move over one another without generating much adhesion or friction[1].From a practical application point of view,this will be the most ideal tribo...Superlubricity refers to a sliding regime in which contacting surfaces move over one another without generating much adhesion or friction[1].From a practical application point of view,this will be the most ideal tribological situation for many moving mechanical systems mainly because friction consumes large amounts of energy and causes greenhouse gas emissions[2].Superlubric sliding can also improve performance and durability of these systems.In this paper,we attempt to provide an overview of how controlled or targeted bulk,surface,or tribochemistry can lead to superlubricity in diamond-like carbon(DLC)films.Specifically,we show that how providing hydrogen into bulk and near surface regions as well as to sliding contact interfaces of DLC films can lead to super-low friction and wear.Incorporation of hydrogen into bulk DLC or near surface regions can be done during deposition or through hydrogen plasma treatment after the deposition.Hydrogen can also be fed into the sliding contact interfaces of DLCs during tribological testing to reduce friction.Due to favorable tribochemical interactions,these interfaces become very rich in hydrogen and thus provide super-low friction after a brief run-in period.Regardless of the method used,when sliding surfaces of DLC films are enriched in hydrogen,they then provide some of the lowest friction coefficients(i.e.,down to 0.001).Time-of-flight secondary ion mass spectrometer(TOF-SIMS)is used to gather evidence on the extent and nature of tribochemical interactions with hydrogen.Based on the tribological and surface analytical findings,we provide a mechanistic model for the critical role of hydrogen on superlubricity of DLC films.展开更多
In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to g...In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction（GGE） biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley（YaRV）, China. Four traits（cotton lint yield, fiber length, lint breaking tenacity, micronaire） and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments： a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none.展开更多
文摘分析了现代军工领域虚拟试验的特性和需求,提出了现代军工领域虚拟试验支撑环境急需解决的问题和研究内容;高级体系结构(High Level Architecture,HLA)、试验与训练使能体系结构(The Test and Training Enabling Architecture,TENA)、虚拟试验床(Virtual Test Bed,VTB)等技术是国外仿真和试验领域比较成熟的研究成果,对我国军工领域虚拟试验支撑环境的研究具有很大的借鉴意义,文中从分布虚拟试验系统的开发、模型集成、系统运行及资源管理等角度分析了HLA、TENA、VTB等的相关技术和研究现状,对我国研究分布虚拟试验的理论和关键技术具有一定的参考价值。
基金supported by the U.S.Department of Energy,Office of Energy Efficiency and Renewable Energy,under Contract No.DE-AC02-06CH11357。
文摘Superlubricity refers to a sliding regime in which contacting surfaces move over one another without generating much adhesion or friction[1].From a practical application point of view,this will be the most ideal tribological situation for many moving mechanical systems mainly because friction consumes large amounts of energy and causes greenhouse gas emissions[2].Superlubric sliding can also improve performance and durability of these systems.In this paper,we attempt to provide an overview of how controlled or targeted bulk,surface,or tribochemistry can lead to superlubricity in diamond-like carbon(DLC)films.Specifically,we show that how providing hydrogen into bulk and near surface regions as well as to sliding contact interfaces of DLC films can lead to super-low friction and wear.Incorporation of hydrogen into bulk DLC or near surface regions can be done during deposition or through hydrogen plasma treatment after the deposition.Hydrogen can also be fed into the sliding contact interfaces of DLCs during tribological testing to reduce friction.Due to favorable tribochemical interactions,these interfaces become very rich in hydrogen and thus provide super-low friction after a brief run-in period.Regardless of the method used,when sliding surfaces of DLC films are enriched in hydrogen,they then provide some of the lowest friction coefficients(i.e.,down to 0.001).Time-of-flight secondary ion mass spectrometer(TOF-SIMS)is used to gather evidence on the extent and nature of tribochemical interactions with hydrogen.Based on the tribological and surface analytical findings,we provide a mechanistic model for the critical role of hydrogen on superlubricity of DLC films.
基金funded by the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX(12)5035)the National Natural Science Foundation of China(30971735)+1 种基金the China Agriculture Research System(CARS-18-20)the Special Fund for Agro-Scientific Research in the Public Interest of China(Impact of Climate Change on Agriculture Production of China,200903003)
文摘In the process to the marketing of cultivars, identification of superior test locations within multi-environment variety trial schemes is of critical relevance. It is relevant to breeding organizations as well as to governmental organizations in charge of cultivar registration. Where competition among breeding companies exists, effective and fair multi-environment variety trials are of utmost importance to motivate investment in breeding. The objective of this study was to use genotype main effect plus genotype by environment interaction（GGE） biplot analysis to evaluate test locations in terms of discrimination ability, representativeness and desirability, and to investigate the presence of multiple mega-environments in cotton production in the Yangtze River Valley（YaRV）, China. Four traits（cotton lint yield, fiber length, lint breaking tenacity, micronaire） and two composite selection indices were considered. It was found that the assumption of a single mega-environment in the YaRV for cotton production does not hold. The YaRV consists of three cotton mega-environments： a main one represented by 11 locations and two minor ones represented by two test locations each. This demands that the strategy of cotton variety registration or recommendation must be adjusted. GGE biplot analysis has also led to the identification of test location superior for cotton variety evaluation. Although test location desirable for selecting different traits varied greatly, Jinzhou, Hubei Province, China, was found to be desirable for selecting for all traits considered while Jianyang, Sichuan Province, China, was found to be desirable for none.
