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101.
阐述了"ABC分析法"和"长尾理论",并将2种方法结合用于农村党员干部现代远程教育视频资源的管理。研究表明,这2种方法的结合使用可以有效实现管理效益。洞察开发视频资源在实际制作中存在的问题,及视频资源在网络教学中面临的实际情况,结合应用"ABC分析法"和"长尾理论",提出了突破这一新课题的管理方法。 相似文献
102.
介绍了建立系统性的高校图书馆文献资源共建共享模式的意义,以及建立共建共享模式过程中存在的困难,并针对困难提出了具体的实施措施。 相似文献
103.
Urban heat island (UHI) often cause negative impact and has been linked to heart stroke rate, morality, human comfort, energy consumption and air pollution. Fortunately, urban green spaces have been considered as an effective element to mitigate UHI through their cooling effect. However, further empirical research is necessary in order to efficiently guide the design and planning of urban green space. We observed the impacts of urban park's tree, grass and waterbody on microclimate inside the Olympic park of Beijing during summer days. The results indicated that, on average, the park was 0.48–1.12 °C cooler during the day, as well as increased air humidity 2.39–3.74% and reduced human comfort index 1.02–2.43 to generate more comfortable thermal environment. Urban park's cluster trees with short ground vegetation generated higher cooling effect than single trees, grass and waterbodies; proper irrigation regime enhanced the cooling effect of grasses, even the irrigated grass have similar cooling effect with small waterbody on sunny, windless summer days. Therefore, we advise to increase undergrowth coverage and grass irrigation management in order to take advantage of cooling effect of urban parks. 相似文献
104.
指出了武穴市位于湖北省东部,隶属于湖北省黄冈市,其地理位置优越,交通便利,旅游资源丰富,但由于是个农业县经济不发达,而且存在着缺乏主题文化及特色旅游活动等问题,严重制约了其旅游发展,使这些年来旅游发展毫无起色。鉴于此,提出了打造“佛国广济,洞天武穴”、大力开发具有武穴乡土特色旅游活动等构想以达到促进武穴市旅游发展的最终目的。 相似文献
105.
Changing an urban environment and replacing vegetated surfaces with low albedo materials is one of the reasons for increasing temperatures in an urban environment and consequently also one of the key causes of urban heat island effects. In this study, an experimental investigation at the micro-scale and also a numerical simulation at the macro-scale of a typical urban environment in Adelaide were conducted to estimate the potential for mitigating the UHI effect. The results showed that existing low albedo materials such as asphalt, metal roofs and brick pavements contribute to the heat island potential. Also, urban development and a lack of natural vegetation contribute to increased temperatures in cities. The ability of two types of extensive and intensive green roofs to reduce the surrounding micro-climate temperature were monitored. The results showed that they have significant cooling effects in summer time and could behave as an insulation layer to keep buildings warmer in the winter. Furthermore, different scenarios of adding green roofs to the Adelaide urban environment were investigated using the Envi–MET model. The scenario modelling of adding green roofs in a typical urban area in Adelaide, Australia, supported the hypothesis that this can lead to reductions in energy consumption in the Adelaide urban environment. Also an increased use of other water sensitive urban design technologies such as green walls and street trees together with the adoption of high albedo materials is recommended for achieving the optimum efficiency in terms of reducing urban temperatures and mitigating urban heat island effects. 相似文献
106.
Acquired Thermo‐Tolerance and Trans‐Generational Heat Stress Response at Flowering in Rice
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In rice, pre‐exposure to sublethal treatment followed by harsh lethal treatment is known to improve tolerance of different abiotic stresses at the vegetative stage within and across generations. Our major aim was to test the phenomenon of thermo‐tolerance at flowering across (trans)‐generations and within generation using rice cultivars contrasting for heat stress tolerance at flowering. To test trans‐generational response, plants were exposed to higher temperature at flowering stage and seeds obtained from previous generations were exposed to heat stress during flowering, which recorded significantly lower fertility when exposed to the same degree of stress in their subsequent generations. A pre‐acclimation to moderately high acclimating temperatures imposed over three different durations during the vegetative and initial reproductive stage showed positive response in the tolerant N22, particularly under severe heat stress (40 °C). This finding indicates the possibility of acquiring ameliorative thermo‐tolerant mechanisms at anthesis, restricted to tolerant genetic backgrounds to combat subsequent harsh conditions within the same generation. However, trans‐generational memory was ineffective in mitigating spikelet sterility losses in both tolerant and susceptible backgrounds. Rice is extremely sensitive to heat stress during flowering; hence, similar exercise across other crops of interest needs to be carried out before generalizing conclusions. 相似文献
107.
The potential of dry heat treatment of Andean lupin seed to reduce seed–borne infection of the anthracnose pathogen, Colletotrichum acutatum, was investigated. First, the effect of dry heat (65 °C) over duration times of 0–96 h on germination and disease incidence after germination was evaluated for artificially– and naturally–infected seed. Dry heat treatment from 8 to 96 h reduced disease incidence after germination to undetectable levels in four cultivars compared with 7.5% disease incidence after germination in seed maintained at room temperature. Moreover, heat treatments of 4–12 h showed seed germination rates that were equivalent to the non–treated control. Under greenhouse conditions, dry heat treatments for 8 or 12 h reduced transmission of the pathogen from seed by 75 or 85%, respectively and dry heat treatment increased emergence of seedlings in comparison the non-treated control. Dry heat treatment is an environmentally friendly alternative for reducing anthracnose infections in Andean lupin seed. 相似文献
108.
109.
相变材料能够储存或释放显热,在熔化或凝固过程中虽然温度不变但吸收的潜热却相当大。根据相变材料可以吸收环境热能并在需要时向环境发出热能的特征,研究相变材料在粮食仓储中的应用,减小外界环境对粮仓温度的影响,达到恒温绿色生态储粮的目的。 相似文献
110.