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41.
舒适度测量仪探测系统主要由采集器、传感器、支架、供水系统、通信模块、数据采集软件6个部分组成.除通信模块之外,其他5个部分都是全新设计.采集器是系统的核心,负责数据的采集、处理和传输;数据采集软件安装在中心服务器上,负责数据的采集、处理、显示和存储,并能远程监测和遥控探测现场的设备.此外,对舒适度的相关理论进行分析,给出适合广州地区的舒适度指数分级标准,并对舒适度测量仪探测数据进行分析.近一年的试运行表明,系统运行稳定、探测数据可靠、适合业务组网的要求.  相似文献   
42.
乌拉特中旗一次寒潮天气过程分析   总被引:1,自引:0,他引:1  
通过对乌拉特中旗2010年3月13—15日的寒潮天气过程,应用天气学原理和方法进行诊断分析,总结出阻高崩溃型寒潮天气过程形成发展的特点以及预报着眼点。  相似文献   
43.
In this paper , by using the seismic data of strong earthquake (M≥7) which have occurred since 1900,correlative features of strong earthquake activity in Tianshan region which crosses China and USSR have been studied . Meanwhile , we selected 15 seismic windows (11 in China , 4 in USSR) by censusing , systematically researching and statistically examing seismic data of regional seismic network which are in Chian and USSR.The anomalous features of seismic window and seismic window network , prediction index and prediction plan have been studied . In the same time ,its prediction efficency have been evaluated . Several examples of successful earthquake prediction are given out in this paper .Finally ,the possible physical mechanism of the results are discussed.  相似文献   
44.
In this study, we have deduced the thermal history of the subducting Neotethys from its eastern margin, using a suite of partially hydrated metabasalts from a segment of the Nagaland Ophiolite Complex (NOC), India. Located along the eastern extension of the Indus‐Tsangpo suture zone (ITSZ), the N–S‐trending NOC lies between the Indian and Burmese plates. The metabasalts, encased within a serpentinitic mélange, preserve a tectonically disturbed metamorphic sequence, which from west to east is greenschist (GS), pumpellyite–diopside (PD) and blueschist (BS) facies. Metabasalts in all the three metamorphic facies record prograde metamorphic overprints directly on primary igneous textures and igneous augite. In the BS facies unit, the metabasalts interbedded with marble show centimetre‐ to metre‐scale interlayering of lawsonite blueschist (LBS) and epidote blueschist (EBS). Prograde HP/LT metamorphism stabilized lawsonite + omphacite (XJd = 0.50–0.56 to 0.26–0.37) + jadeite (XJd = 0.67–0.79) + augite + ferroglaucophane + high‐Si phengite (Si = 3.6–3.65 atoms per formula unit, a.p.f.u.) + chlorite + titanite + quartz in LBS and lawsonite + glaucophane/ferroglaucophane ± epidote ± omphacite (XJd = 0.34) + chlorite + phengite (Si = 3.5 a.p.f.u.) + titanite + quartz in EBS at the metamorphic peak. Retrograde alteration, which was pervasive in the EBS, produced a sequence of mineral assemblages from omphacite and lawsonite‐absent, epidote + glaucophane/ferroglaucophane + chlorite + phengite + titanite + quartz through albite + chlorite + glaucophane to lawsonite + albite + high‐Si phengite (Si = 3.6–3.7 a.p.f.u.) + glaucophane + epidote + quartz. In the PD facies metabasalts, the peak mineral assemblage, pumpellyite + chlorite + titanite + phengitic white mica (Si = 3.4–3.5 a.p.f.u.) + diopside appeared in the basaltic groundmass from reacting titaniferous augite and low‐Si phengite, with prehnite additionally producing pumpellyite in early vein domains. In the GS facies metabasalts, incomplete hydration of augite produced albite + epidote + actinolite + chlorite + titanite + phengite + augite mineral assemblage. Based on calculated TM(H2O), T–M(O2) (where M represents oxide mol.%) and PT pseudosections, peak PT conditions of LBS are estimated at ~11.5 kbar and ~340 °C, EBS at ~10 kbar, 325 °C and PD facies at ~6 kbar, 335 °C. Reconstructed metamorphic reaction pathways integrated with the results of PT pseudosection modelling define a near‐complete, hairpin, clockwise PT loop for the BS and a prograde PT path with a steep dP/dT for the PD facies rocks. Apparent low thermal gradient of 8 °C km?1 corresponding to a maximum burial depth of 40 km and the hairpin PT trajectory together suggest a cold and mature stage of an intra‐oceanic subduction zone setting for the Nagaland blueschists. The metamorphic constraints established above when combined with petrological findings from the ophiolitic massifs along the whole ITSZ suggest that intra‐oceanic subduction systems within the Neotethys between India and the Lhasa terrane/the Karakoram microcontinent were also active towards east between Indian and Burmese plates.  相似文献   
45.
Lakes regulate the water and heat exchange between the ground and the atmosphere on different temporal and spatial scales. However, studies of the lake effect in the high-altitude Tibetan Plateau(TP) rarely have been performed until recently, and little attention has been paid to modelling of frozen lakes. In this study, the Weather Research and Forecasting Model(WRF v. 3.6.1) is employed to conduct three numerical experiments in the Ngoring Lake Basin(the original experiment, an experiment with a tuned model, and a no-lake experiment) to investigate the influences of parameter optimization on the lake simulation and of the high-altitude lake on the regional climate. After the lake depth, the roughness lengths, and initial surface temperature are corrected in the model, the simulation of the air temperature is distinctly improved. In the experiment using a tuned model, the simulated sensible-heat flux(H) is clearly improved, especially during periods of ice melting(from late spring to early summer) and freezing(late fall). The improvement of latent-heat flux(LE) is mainly manifested by the sharp increase in the correlation coefficient between simulation and observation, whereas the improvement in the average value is small. The optimization of initial surface temperature shows the most prominent effect in the first year and distinctly weakens after a freezing period. After the lakes become grassland in the model, the daytime temperature clearly increases during the freezing and melting periods; but the nocturnal cooling appears in other stages, especially from September to October. The annual mean H increases by 6.4 times in the regions of the Ngoring Lake and the Gyaring Lake, and the LE declines by 56.2%. The sum of H and LE increases from 71.2 W/m2(with lake) to 84.6 W/m2(no lake). For the entire simulation region, the sum of H and LE also increases slightly. After the lakes are removed, the air temperature increases significantly from June to September over the area corresponding to the two lakes, and an abnormal convergence field appears; at the same time, the precipitation clearly increases over the two lakes and surrounding areas.  相似文献   
46.
Pan  Yongjie  Lyu  Shihua  Li  Suosuo  Gao  Yanhong  Meng  Xianhong  Ao  Yinhuan  Wang  Shujin 《Theoretical and Applied Climatology》2017,127(3-4):1011-1022

Soils containing gravel (particle size ≥2 mm) are widely distributed over the Qinghai–Tibet Plateau (QTP). Soil mixed with gravel has different thermal and hydrological properties compared with fine soil (particle size <2 mm) and thus has marked impacts on soil water and heat transfer. However, the most commonly used land models do not consider the effects of gravel. This paper reports the development of a new scheme that simulates the thermal and hydrological processes in soil containing gravel and its application in the QTP. The new scheme was implemented in version 4 of the Community Land Model, and experiments were conducted for two typical sites in the QTP. The results showed that (1) soil with gravel tends to reduce the water holding capacity and enhance the hydraulic conductivity and drainage; (2) the thermal conductivity increases with soil gravel content, and the response of the temperature of soil mixed with gravel to air temperature change is rapid; (3) the new scheme performs well in simulating the soil temperature and moisture—the mean biases of soil moisture between the simulation and observation reduced by 25–48 %, and the mean biases of soil temperature reduced by 9–25 %. Therefore, this scheme can successfully simulate the thermal and hydrological processes in soil with different levels of gravel content and is potentially applicable in land surface models.

  相似文献   
47.
近年来,地震窗预报方法已在国内广为应用。富蕴地震窗系笔者在王泽皋、姜秀娥等人工作的基础上[1-3],于1984年在全国地震预报清理攻关中建立,在1987-1988年全国地震预报实用化攻关中又得以进一步深化和完善[4]。  相似文献   
48.
49.
针对传统的边缘检测方法将灰度变化较为平缓的区域误判为边缘的问题,提出了基于二阶局部纹理熵的边缘检测方法。利用了二阶局部纹理熵能表示局部区域灰度变化大小的性质,并采用灰度错位压缩法消除灰度值压缩造成的条纹现象。实验表明,本文提出的方法能有效地检测出各类边缘,解决了上述的误判问题;通过不同大小窗口的边缘检测效果比较,建议在采用基于二阶局部纹理熵的边缘检测方法时将窗口设置为3×3。  相似文献   
50.
Natural hillslopes are mostly composed of complex slope shapes, which significantly affect soil erosion. However, existing studies have mainly focused on uniform slopes to simplify complex hillslopes, and the mechanisms responsible for the influence of slope shape on soil and nutrient losses are still not well understood, especially in the application of soil improvers to reduce soil loss. To investigate the effects of slope shape and polyacrylamide (PAM) application on runoff, soil erosion and nutrient loss, this study conducted artificial field rainfall experiments involving two PAM application rates and nine slope shapes. The results indicate that the average amount of soil loss from convex slopes was 1.5 and 1.3 times greater than that from concave and uniform slopes, respectively, and the average amount of ammonia nitrogen loss and phosphate loss increased by 24.0%–58.6%. Soil and nutrient losses increased as the convexity of the convex slopes increased. For runoff, there was little difference between concave and convex slopes, but the runoff amount for both slopes was greater than that for uniform slopes. After PAM application, the soil loss decreased by more than 90%, and the nutrient loss decreased by 28.2%–68.1%. The application of PAM was most effective in reducing soil erosion and nutrient loss from convex slopes, and it is recommended to appropriately increase the PAM application rate for convex slopes. A strong linear relationship between ammonia nitrogen and phosphate concentrations and sediment concentrations was found in the runoff on slopes with no PAM application. However, this linear relationship weakened for slopes with PAM application. The findings of this study may be valuable for optimizing nonpoint source pollution management in basins.  相似文献   
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