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11.
运用ELES模型,对2005～2009年江苏省城镇居民的消费结构以及基本需求弹性进行了研究,在实证分析的基础上归纳出了江苏省居民在消费中存在的问题,并为合理规范化消费提出了对策与建议。 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(2):150-157
An outbreak of the needle-shortening pine gall midge, Thecodiplosis brachyntera , occurred on Scots pine, Pinus sylvestris (L.) and lodgepole pine, P. contorta (Dougl.) in central Sweden during 1995-1998. The larval feeding of T. brachyntera kills current-year needles and heavy infestation causes severe defoliation. A pattern of fluctuating defoliation among years and sites was found on both pine species. Defoliation was evenly distributed in the crown of P. sylvestris during years of high as well as low infestation; apical whorls had as much defoliation as basal whorls. In P. contorta , however, there was a tendency for defoliation to be concentrated on branches in the most apical whorls. Growth ring increments on P. sylvestris with high levels of defoliation (71%) did not differ from trees with moderate levels (26%) of defoliation. Shoot lengths were significantly shorter, however, on heavily infested trees the year after defoliation. 相似文献
13.
我国农村居民茶叶消费特点之实证分析 总被引：2，自引：0，他引：2
本文利用扩展线性支出系统等计量经济模型,求出茶叶的边际消费倾向和需求收入弹性并进行比较分析,揭示我国农村居民茶叶消费的现状和特点,为茶叶经营策略的制订提供参考依据。 相似文献
14.
基于扩张状态观测器的路面附着系数实时估计 总被引：2，自引：0，他引：2
对车辆动力学控制中的道路路面附着系数实时估计问题进行研究.首先使用魔术公式建立1/4车辆制动模型,即车轮制动动力学模型;然后将其中的附着系数相关项视为制动系统的扩张状态,建立其扩张状态观测器,通过轮速信号和制动力矩信号实时观测制动过程中地面与轮胎间的纵向力,进而计算出路面附着系数;最后在均匀路面和突变路面条件下进行仿真研究.结果表明,所提出的方法对车辆制动系统参数摄动和传感器噪声具有鲁棒性,可以准确地实现道路路面附着系数的实时估计,观测器与控制器设计具有一定独立性. 相似文献
15.
拓展公共图书馆服务领域延伸多元化服务 总被引：1，自引：0，他引：1
李瑞波 《农业图书情报学刊》2011,23(4):185-189
对图书馆延伸服务工作的重要意义进行了系统分析,提出了公共图书馆要抓住拓展服务功能的新契机,延伸多元化服务,并对公共图书馆延伸服务面临的生存与发展问题做了进一步探讨。 相似文献
16.
孙娇 《农业图书情报学刊》2014,(2):192-194
随着网络信息技术的迅猛发展,高校图书馆的参考咨询服务应该寻求进一步的个性化发展。在此阐述了数字参考咨询延伸服务的概念,并分析了高校图书馆开展数字参考咨询延伸服务的必要性和可行性,并提出了国内高校图书馆数字参考咨询延伸服务实现的策略。 相似文献
17.
Weiss A Del Pino P Bertsch U Renner C Mentler M Grantner K Moroder L Kretzschmar HA Parak FG 《Veterinary microbiology》2007,123(4):358-366
The cellular prion protein (PrP(C)) is a copper binding protein. The molecular features of the Cu(2+) binding sites have been investigated and characterized by spectroscopic experiments on PrP(C)-derived peptides and the correctly folded human full-length PrP(C) (hPrP-[23-231]). These experiments allowed us to distinguish two different configurations of copper binding. The different copper complexes depend on sequence context, buffer conditions and stoichiometry of copper. The combined information of spectroscopic data from our EXAFS, EPR and ENDOR experiments was used to create models for these two copper complexes. A large number of conformations of these models were calculated using molecular mechanics computations, and the simulated spectra of these structures were compared with our experimental data. Common features and differences of the copper binding motifs are discussed in this paper and it remains for future investigations to study whether different configurations are associated with different functional states of PrP(C). 相似文献
18.
L.A. Wunsch 《Research in veterinary science》2010,88(1):154-158
The purpose of this study was to evaluate arterial blood gases in dogs that were given hydromorphone or extended release liposome-encapsulated hydromorphone (LEH). Dogs were randomly administered LEH, n = 6, (2.0 mg kg−1), hydromorphone, n = 6, (0.2 mg kg−1) or a placebo of blank liposomes, n = 3, subcutaneously on separate occasions. Arterial blood samples were drawn at serial time points over a 6-h time period for blood gas analysis. There was no change from baseline values in PaCO2, PaO2, (HCO3-), pH, and SBEc in the dogs that received the placebo. Administration of hydromorphone resulted in significant increases in PaCO2 (maximum (mean + SD] 44.4 + 1.1 mm of Hg) and significant decreases in PaO2 (minimum (mean + SD) 82.4 + 4.7 mm of Hg) and pH (minimum (mean + SD) 7.31 + 0.01) compared with baseline. Administration of LEH resulted in significant increases in PaCO2 (maximum (mean + SD) 44.6 + 0.9 mm of Hg) and significant decreases in PaO2 (minimum (mean + SD) 84.8 + 2.6 mm of Hg) and pH (minimum (mean + SD) 7.34 + 0.02) compared with baseline. There was no significant difference between these two groups at any time point. The changes observed in PaCO2, PaO2, and pH, however, were within clinically acceptable limits for healthy dogs. LEH was determined to cause moderate changes in arterial blood gas values similar to those caused by hydromorphone. 相似文献
19.
Field experiments were conducted in 2003 and 2004 to evaluate full and reduced input fungicide programs in peanut fields with varying levels of risk for the peanut leaf spot complex (caused by Cercospora arachidicola and Cercosporidium personatum). Fungicides applications were made on a 14-, 21-, or 28-day interval (d.i.). Leaf spot intensity was similar for all programs in fields considered to be low or moderate risk; however, there was more leaf spot in plots treated on a 28-d.i. for high risk fields. Incidence of stem rot (caused by Sclerotium rolfsii) was lower in plots treated with soilborne-based programs than those treated with foliar-based programs. Control for the 21- and 28-d.i. soilborne-based programs was comparable to that for the 14-d.i. program in all trials except the high risk situations where plots treated on the 28- d.i. had higher levels of stem rot. Pod yields were similar among application intervals for all trials. Based on these results, reductions in the number of fungicide applications can be made without compromising leaf spot control, stem rot control, or yield. 相似文献
20.
赵迎春 《农业图书情报学刊》2011,23(2):200-203
公共图书馆开展延伸服务,有利于优化图书馆资源配置,最大限度地发挥政府投入的社会效益。基于此,山西省图书馆在开展传统阵地服务的同时,扩大服务对象,延伸服务领域,拓展服务空间,使图书馆的服务广度和深度都得到了延伸,有效提高了自身的公共文化服务能力。 相似文献