云南蹄盖蕨属一新种和一新杂种     

谢寅堂  王中仁 《中国科学院研究生院学报》1989,27(2):155-157

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Dynamic Stackelberg games under open-loop complete information     

Pu-yan Nie 《Journal of The Franklin Institute》2005,342(7):737-748

Stackelberg games, which play extremely important roles in such fields as economics, management, politics and behavioral sciences, can be modelled as a bilevel optimization problem. There exist extensive literatures about static bilevel optimization problems. However, the studies on dynamic bilevel optimization problems are rather scarce in spite of the importance in explaining and predicting some phenomena rationally. In this paper, discrete time dynamic Stackelberg games with open loop complete state are revisited. An example, which comes from law field, is presented as an open-loop Stackelberg game to illuminate the rangy application of game theory. A property based on Bellman's equation is proposed without any restriction about inner point solution for open-loop Stackelberg games in this work. Moreover, we point out that open-loop Stackelberg games perform no better than both feedback and closed-loop dynamic Stackelberg games with complete information, which seems quite valuable to explain some social and economic phenomena.  相似文献   

冰芯气候环境记录研究：从科学到政策          下载免费PDF全文

姚檀栋  秦大河  王宁练  刘勇勤  徐柏青 《中国科学院院刊》2020,35(4):466-474

冰芯是过去气候环境变化信息的重要载体。文章着重阐述了三极(南极、北极和第三极)冰芯研究在揭示过去气候变化、大气温室气体含量变化、太阳活动、火山活动及人类活动等方面所取得的成就,并说明冰芯研究对相关环境政策制定(如含铅汽油禁用政策、温室气体减排政策)的推动作用。建议国家尽快建立冰芯档案储藏库,以拯救冰芯资源,为后世科学研究与国家发展服务。  相似文献   

三种结缕草试管繁殖研究     

柴明良  胡叔良 《科技通报》1993,9(6):411-415

以结缕草属的马尼拉草、结缕草和中华结缕草进行了试管繁殖的研究.以马尼拉草匍匐茎为外植体,通过芽直接增殖和愈伤组织分化途径形成了2个试管无性系;从结缕草和中华结缕草的实生苗中也筛选出了若干个试管无性系.嫩极丛在1/2MS培养基添加IBA或 NAA0.5 mg/L、IBA0.25mg/L+NAAO.25mg/L上生根,经38 d培养,马尼拉草生根率为100％,结缕草为88％～90％.移栽成活率马尼拉草在95％以上,结缕草高于90％.试管草移栽后生长旺盛。  相似文献   

冈底斯中段尼木斑岩铜矿田的K-Ar、^40 Ar/^39 Ar年龄：对岩浆-热液系统演化和成矿构造背景的制约          下载免费PDF全文

李金祥秦克章  李光明杨列坤 《中国科技期刊研究》2007,23(5):953-966

青藏高原冈底斯斑岩成矿带不同于经典的产于岛弧和大陆边缘的斑岩铜矿,而形成于后碰撞挤压向伸展转变期,显示了极好的成矿前景.本文对冈底斯中段尼木矿田白容、厅宫和冲江斑岩铜矿区斑岩体进行了系统研究,确定出斑岩体演化和侵入序列为：似斑状二长花岗岩→成矿二长花岗斑岩→石英闪长玢岩→花岗闪长斑岩.K-Ar和^40 Ar/^39 Ar年代学研究获得白容矿区似斑状二长花岗岩中角闪石的K-Ar年龄为16.9±2.4Ma;石英闪长玢岩中黑云母的K-Ar年龄为12.3±0.2Ma、^40 Ar/^39 Ar坪年龄为12.5±0.2Ma;花岗闪长斑岩中黑云母的K-Ar年龄为11.5±0.2Ma、^40 Ar/^39 Ar坪年龄为12.4±0.2Ma;厅宫矿区石英闪长玢岩中黑云母的K-Ar年龄为13.8±0.2Ma、^40 Ar/^39 Ar坪年龄为14.9±0.2Ma;花岗闪长斑岩中黑云母的K-Ar年龄为13.5±0.3Ma、^40 Ar/^39 Ar坪年龄为14.2±0.2Ma,这些年龄表明：石英闪长玢岩晚于似斑状二长花岗岩,略早于花岗闪长斑岩.成矿与二长花岗斑岩有关,其侵位时间晚于似斑状二长花岗岩,早于石英闪长玢岩和花岗闪长斑岩.尼木癍岩铜矿田这种复式杂岩体较充分的分异演化有利于含矿热液的集中与逐渐富集成矿.白容斑岩铜矿蚀变矿化二长花岗斑岩的蚀变绢云母的K-Ar年龄为11.8±0.2Ma,^40 Ar/^39 Ar坪年龄为12.0±0.1Ma,代表了中低温蚀变和矿化末期的年龄.白容矿区绢云母化带的蚀变年龄与石英闪长玢岩和花岗闪长斑岩的黑云母^40 Ar/^39 Ar年龄基本一致,与厅宫矿区辉钼矿Re-Os年龄及石英闪长玢岩和花岗闪长斑岩的黑云母^40 Ar/^39 Ar年龄同样基本一致,暗示两个矿区石英闪长玢岩和花岗闪长斑岩的岩浆结晶冷却与成矿二长花岗斑岩后期热液成矿时间上有重叠.结合前人年龄数据大致确定出白容矿区岩浆-热液活动时限为0.5～5Ma,厅宫为4Ma,冲江为4.5Ma.尼木矿田成矿斑岩^40 Ar/^39 Ar年龄晚于冈底斯碰撞后第一次快速隆升时间≈21Ma,15Ma冈底斯中段NS向正断层开始活动,表明含矿斑岩体可能侵位于地壳加厚、冈底斯山大规模隆升到一定程度后出现弱伸展环境的构造背景下,即斑岩铜矿形成于从南北向挤压隆升到东西向伸展初始发育的过渡构造背景.  相似文献   

中国金藻门植物的新种类     

施之新 《中国科学院研究生院学报》1997,35(3):269-272

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冷杉属一新种——梵净山冷杉     

黄威廉  屠玉麟  杨龙 《中国科学院研究生院学报》1984,22(2):154-155

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形式化方法--Z语言在西瓜棋中应用的研究   总被引：1，自引：0，他引：1  

邓达平  王命延 《科技广场》2005,(2):12-15

Z语言是目前广泛使用的一种形式化方法语言。它具有简明、精确、无歧义的优点。本文利用Z语言对一种棋类游戏——西瓜棋进行了描述，并给出了西瓜棋游戏从状态模式到操作模式的需求规格说明。  相似文献   

论我国团体标准化主体边界之认定     

陈俊华  许方  李美青 《科技管理研究》2019,39(7)

团体标准具有促进科技创新等重要作用。在我国有关团体标准的主体制度中，是否要对团体标准化主体的边界以“法人资格”为限制，值得进一步讨论。实践中，存在一定数量的产业技术联盟等社会团体可能未获“法人资格”，但却具备了开展团体标准化活动的专业能力。诚然，无须将“法人资格”作为硬性的准入门槛，而应将“专业能力”作为必备的资格条件，并突出技术组织对团体标准化活动的的支撑作用。继而有必要通过法制化路径引入主体备案制度，为非法人社会团体在标准化领域创造合法空间，从而在一定程度上缓解实际需求与相对严苛的现行法律环境之间的张力。  相似文献   

‘Tomorrow's Schools’ in New Zealand: from social democracy to market managerialism   总被引：1，自引：1，他引：0  

Marian Court  John O’Neill 《Journal of educational administration and history》2011,43(2):119-140

This paper uses one national case to illustrate how diverse ideological agendas of central state agencies contest the discursive space within which major education policy reforms are developed. In Aotearoa New Zealand in 1988, ‘self‐managed’ schools were promoted ostensibly to allow parents more say in their children’s education and local school administration. The Tomorrow’s Schools reform policy texts included an existing social democratic partnership rhetoric, positioning principals as professional leaders working collaboratively with elected parent boards of trustees. However, the new ideology of ‘parental choice’ of school within a local schooling marketplace, underpinned by a chief executive or market managerial model of principalship, was later operationalised through mechanisms of ‘steerage’ from the centre. To explain this shift, we examine selected policy text pre‐cursors to the reforms and identify how contrasting forms of ‘principal’ and ‘teacher’ identity emerged within social democratic, neo‐liberal and market managerial ideologies. We further show that while radical (Treasury) market liberal arguments for labour market deregulation and consumer choice failed to gain widespread support, the State Services Commission preferred market managerialist strategies for promoting public accountability of schools (based on aggregate student achievement outcome data and centrally determined national educational priorities) were successfully embedded during the 1990s.  相似文献