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到报监测是气象水文数据传输、处理等的重要环节,其实时性是关键设计目标。通过分析文件目录扫描方法和消息通知机制的应用特点,结合气象水文资料传输、处理规程及应用模式,重点阐述了结合实时性和可靠性要求的到报监测方法,并给出一种重构性强、应用灵活的到报监测模块的设计方案。 相似文献
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Bashagaluke Janvier Mulumuna Janvier Pieter Pypers Walangululu Jean Shepherd Keith MochogeBenson Mugwe Jayne Vanlauwe Bernard Boeckx Pascal 《农业科学与技术》2013,(9):677-688
Recently, near infrared reflectance (NIR) and mid-infrared (MIR) spectroscopy techniques are increasingly introduced as convenient and simple non-destructive techniques for quantifying several soil properties. This study uses MIR method to predict pH, soil organic C, total N, AI, Ca, Mg and K, CEC and soil texture for soil samples collected in Sud-Kivu, Congo. A total of 536 composite soil samples were taken from two locations (Burhale and Luhihi) at two depths (0-20 cm and 20-40 cm) using a spatially-stratified random sampling design within an area of 200 km2. Differences in characteristics were evaluated between the two locations, land use (cultivated vs. non-cultivated land) with soil depths. A random subset of the samples (10%) were analyzed using standard wet chemistry methods, and calibration models developed by MIR data to estimate soil properties for the full soil sample set. Partial least squares regression (PLS) method gave acceptable coefficients of determination between 0.71 and 0.93 for all parameters. Soil organic matter levels were higher in cultivated plots in Luhihi (3.9% C) than in Burhale (3.0% C), suggesting lower levels of soil fertility in the later area. This indicates high levels of acidity, which are likely to limit crop production in the area. Phosphorus deficiency is acute in Burhale (2.4 mg P/kg) but less in Luhihi (5.4 mg P/kg). In both locations, low levels of Ca and Mg indicate that soils may be susceptible to deficiencies in both elements.These findings provide new opportunities for monitoring soil quality in the region which can benefit multiple actors and scientists involved in the agricultural and environmental sectors. 相似文献
105.
针对木材表面存在纹理、凹凸结构、边缘颗粒和弱边缘等特点,对其直接运用Snake模型进行分割难以得到有效边缘提取,因此提出运用改进的GVF Snake模型和维纳滤波相结合对其进行分割。首先对木材图像进行维纳滤波使得纹理变得平缓,同时可以使得缺陷边缘得到有效保留,再对其进行GVF Snake模型分割。该算法对初始轮廓的选择敏感度降低,拓展性增强,可以使得轮廓曲线更加快速地收敛到缺陷边缘,避免陷入局部最优现象,提高对弱边缘和凹凸图像分割效果,分割结果更加清晰、连贯,具有良好的实时性。为木材表面缺陷的分割提供一种更为有效的方法,拓宽了snake模型的应用范围。 相似文献
106.
应用Excel计算集中供热工程的投资估算。首先创建估算的模板,再应用模板来计算具体建设规模的投资估算,其应用过程简便、快捷、准确、科学。 相似文献
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本研究旨在检测内源性绵羊肺腺瘤反转录病毒(enJSRV)与干扰素-τ(IFN-τ)在妊娠早期蒙古绵羊子宫内膜组织的表达以及enJSRV的表达与外周血孕酮水平变化的关系。运用TaqMan实时荧光定量PCR技术和电化学发光法对enJSRV和IFN-τ在妊娠早期蒙古绵羊子宫内膜组织相对表达及孕酮水平进行了测定。实时荧光定量PCR结果显示,enJSRV和IFN-τmRNA在妊娠早期绵羊子宫内膜组织有不同程度的表达。SAS统计学软件分析得出,子宫内膜组织中enJSRV mRNA在妊娠12~14d(交配日为0d)表达较高,2~10、16~30d的表达均低于前者。IFN-τmRNA仅在妊娠12~25d表达,14d达其峰值,30d就不能检出,且差异都极显著(P<0.01)。电化学发光法结果显示,孕酮水平在妊娠2d为0.4ng·mL-1,以后升高,妊娠8~16d维持在8.3ng·mL-1左右,在妊娠19~30d孕酮水平有所下降,30d为2.5ng·mL-1。以上结果提示,子宫内膜组织中enJSRV mRNA的表达与外周血孕酮含量及IFN-τ的变化高度相关,且enJSRV在胎盘的形态发生及生殖生物学方面发挥重要作用。 相似文献
108.
J. ROBINSON 《Plant Breeding》2000,119(3):219-222
Five Nordic spring barley lines (‘Rolfi’, ‘Arve’, ‘Botnia’, ‘Pohto’ and WW7977) and doubled haploid (DH) populations from a half diallel of crosses between them, were sown in the field in Finland over 2 years and were artificially infected with Pyrenophora teres, the causal agent of net blotch. The purpose of the experiments was to determine the extent of yield loss under net blotch infection in a range of parent barleys and DH populations differing in symptom expression. Analysis of foliar damage symptoms, yield and aerial biomass data indicated that, in both years, there were statistically significant differences among parents and crosses, but the relationships between symptom expression and yield maintenance and between symptom expression and aerial biomass maintenance were stronger in 1997, when yields were higher and net blotch was less severe. 相似文献
109.
Forest fragmentation in Loudoun County,Virginia, USA evaluated with multitemporal Landsat imagery 总被引:1,自引:0,他引:1
In order to study forest fragmentation in the Virginia, USA Piedmont, a series of Landsat images from 1973, 1987, and 1999 covering a rapidly developing area (Loudoun County) was used to classify forest from non-forest. The classified images were analyzed using a geographic information system (GIS) to determine the spatial and temporal patterns of fragmentation, and to relate these patterns to infrared radiance provided by Landsat Enhanced Thematic Mapper Plus (ETM+) band 6. The analysis was concentrated on eleven major watersheds of Loudoun County. The relationship between urbanized area per watershed and mean fragment size showed a strong negative decay form (r
2=0.757, p<0.0001). Analysis of four landscape metrics showed increasing fragmentation of forest cover, particularly from 1987 to 1999, as well as an increase in forest edge and shape complexity. Of the landscape metrics used, the perimeter-to-area (P/A) ratio showed the strongest relationship with mean radiance of forest patches. In addition, there was a negative, linear relationship between distance from major roads and band 6 radiance of forested pixels. Overall, the study shows that landscape metrics can convey meaningful information on biophysical changes associated with forest fragmentation at broad scales. These changes suggest that ambient temperature increases associated with urban sprawl may have important, long-term implications for ecophysiological processes. 相似文献
110.