黄土高原半湿润区玉米生长发育及产量形成对气候变化的响应   总被引：6，自引：0，他引：6  

姚玉璧  王瑞君  王润元  杨金虎  张谋草  肖国举 《资源科学》2013,35(11):2273-2280

利用黄土高原半湿润区西峰农业气象试验站玉米生长发育观测资料、加密观测和对应平行气象观测资料,分析气候变化对玉米生长发育的影响,以及玉米穗干重生长与气象条件的关系。结果表明,1951-2010年,试验区逐年降水量呈波动变化,20世纪90年代降水量较其他年代为最少。降水量序列3a、8a的周期变化特征明显。试验区逐年气温为上升趋势,逐年气温序列线性拟合气候倾向率为0.325℃/10a。逐年作物生长季干燥指数显著上升,逐年干燥指数序列线线性拟合气候倾向率为0.051/10a,进入20世纪70年代,试验区气候暖干化特征明显。气候变暖使玉米拔节－成熟期提前(5~6)d/10a,全生育期缩短。玉米穗干重在播种102 d后,从缓慢生长期转为迅速生长期,在播种129 d后,又从迅速生长期转为缓慢生长期,玉米穗的干物质积累最大速率出现在播后115d左右。气候变暖使玉米大部分生育期可利用热量资源充裕,玉米产量形成对抽雄－开花期气温变化十分敏感,大部分时段气温对玉米产量形成呈负效应。气温变化的影响函数与降水量变化的影响函数表现为反相位特征。在玉米成熟期,降水对产量的影响为负效应,其余生育期降水的影响为正效应,玉米产量形成对三叶－拔节期降水变化十分敏感。灌浆－成熟期光照对玉米产量形成呈显著的正效应。  相似文献   

区域创新系统视野下的企业技术创新过程研究     

伍虹儒 《大众科技》2013,(2):112-115

根据区域创新系统的观点,企业的技术创新过程不是孤立进行的。在技术创新过程中,企业和政府、高等学校、研究机构和上下游企业不断进行信息、技术和人才的相互作用。本文从区域创新系统角度出发,研究企业创新过程,分析企业在技术创新过程中存在的瓶颈因素,提出政策建议。  相似文献   

浅析中职学校留守学生及其成长教育     

朱卉虹 《大众科技》2013,(6):230-231,244

文章通过分析留守学生成因、成长过程,关注、关心留守学生的成长。学校教育应重视留守学生的成长教育。首先分析留守学生出现的症状,学校教育对症下药,采取相应的措施对留守学生成长进行教育。论证了留守学生需要家长配合学校进行教育;学校和教师应以高度的责任心并以实际行动关心留守学生成长做出应有的贡献。  相似文献   

数字化对出版企业经营管理的影响与对策     

缪莉 《科学与管理》2013,(1):77-82

我国出版业面临数字化大变革,产业形态的升级换代己进入加速期。目前,推动传统出版企业向数字出版转型成为行业的核心任务之一。数字化改变了企业的经营战略和出版方式,改变了企业的内容、制作、传播、销售和增值服务等所有重要出版环节,催生了新型业态和新型的营销渠道,使出版企业的经营管理面临脱胎换骨的改造。本文从出版企业产业链各重要环节入手,着重探讨了数字化对出版企业经营管理的影响,提出了出版企业为顺应数字出版潮流在经营管理上应采取的对策措施,以对出版业数字出版的良性发展有所助益。  相似文献   

北京旅游纪念品市场消费满意度实证研究     

邹毅  李诗萌戴维肖 《科学与管理》2013,(6):84-87

基于对北京5个重点景区游客的随机问卷调查,同时借鉴美国顾客满意度指数ACSI模型,构建了包括旅游纪念品感知特色、感知质量、感知价值和总体消费满意度在内的北京旅游纪念品市场消费满意度测评模型,并利用SPSS和AMOS软件对北京旅游纪念品市场发展现状进行评价与研究。在此基础上,以北京旅游委特色旅游开发项目"北京礼物"为重点案例,与北京总体旅游纪念品市场满意度现状对比分析,结果表明,"北京礼物"在感知价值和感知质量测量指标上的优势决定了其远高于市场平均水平的满意度,深入挖掘"北京礼物"的商业模式对旅游纪念品行业有重要意义。  相似文献   

高新技术小微企业人力资源之困及其对策     

杨波 《科技广场》2013,(7):200-203

高新技术小微企业的核心竞争力就是其智力资源。本文结合小微企业规模小、资金短缺、前景不明朗、核心技术人员流失严重的实际,根据核心技术人员的需求和工作特点,提出员工招聘走校企联合,"订单"人才培养模式,对核心技术人员进行非对称性虚拟股权激励,在生产经营过程中发挥小微企业自身的比较优势,利用电子商务、服务外包等以节约人力资源,对于离职员工从工作流程文档化和法律层面保护企业利益,多管齐下,以解决小微企业发展过程中的人力资源瓶颈。  相似文献   

Multi-Agent系统基于优先级的负载均衡任务调度模型*     

翟东升  李莉 《现代图书情报技术》2007,2(8):34-39

从企业收集、监测互联网信息的实际需求出发，介绍基于Multi-Agent的分布式信息采集系统的结构模型；重点阐述中心控制Agent在组间层次上、调度Agent在组内层次上基于优先级的任务调度算法；为达到系统中运行任务Agent的各节点主机负载均衡，给出调度Agent与任务Agent间的组内协商机制；对系统原型的测试结果表明，基于优先级的负载均衡任务调度模型的正确性与有效性。  相似文献   

Public narratives under intensified market conditions: Chile as a critical case     

Diego Santori 《Discourse: Studies in the Cultural Politics of Education》2018,39(1):53-68

This paper aims to extend existing theorisations around the notion of public narratives by analysing their regulatory effects under intensified market conditions. My analysis suggests that public narratives constitute a liminal space, one that it is not exclusively real or imaginary, factual or normative, but that simultaneously affects and is affected by vernacular practices and wider discursive structures. However, this paper argues that, under extreme conditions, these public narratives become a rigidifying space with homogenising/normalising effects. To do this I look at a set of ‘obligatory scenes’ captured in tales of success and struggle of teachers, parents and students in popular newspapers and fringe media in Chile. These accounts share a common ground: national assessment as a framework of intelligibility for the practices of parents, teachers and students. The central claim of this paper is that under intensified market conditions the scenes captured in these publicly available stories become ‘obligatory’ storylines, and their protagonists idealised policy subjects.  相似文献   

Upward and downward job mobility and player market values in contemporary European professional football     

《Sport Management Review》2019,22(2):209-221

One question facing professional football (soccer) players in today's highly mobile football labor market is how to move between teams and develop boundaryless careers that positively signal their qualities, skills, and value to the market. The author departs from previous researchers, who have conceptualized market values as a function of performance and human capital factors at one point in time. Instead, the author argues that market observers face imperfect information when estimating the value of players, which they overcome by using job mobility as a signal for the qualities, skills, and playing potential of footballers. Analyzing a unique longitudinal dataset of 1670 professional player careers with fixed effects panel regressions, results indicate that upward mobility is a positive signal shifting observers' estimations of player market values up and downward mobility is a negative signal pushing market values down. Each extra move up leads to an additional increase in market values and the negative impact of downward mobility decreases when players take up more important roles in their new team. The impact of mobility on player market values is thus contingent on broader career patterns and the context in which job mobility takes place.  相似文献   

Interaction effect of strategic leadership behaviors and organizational culture on IS-Business strategic alignment and Enterprise Systems assimilation     

《International Journal of Information Management》2019

Drawing upon strategic leadership theory, this study develops a theoretical model to explore the impact of senior executives’ leadership behaviors on IS-Business strategic alignment in the context of Enterprise Systems (ES) assimilation. In particular, organizational culture is added as a critical moderator in the research model based on contingency theory. Empirical analysis results suggest that idealized influence and inspirational motivation leadership behaviors are significant drivers of IS-Business strategic alignment, which further has a positive influence on Enterprise Systems assimilation. Moreover, flexibility-oriented culture positively moderates the relationship between strategic leadership behaviors and IS-Business strategic alignment, while control-oriented culture negatively moderates the path relationships. Our study contributes to the extant literature in both leadership and IS-business strategic alignment.  相似文献