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31.
严蓓兰 《航空动力学报》2018,45(7):84-88, 115
为积极响应《中国制造2025》以及《工业和信息化部办公厅关于开展绿色制造体系建设的通知》,针对我国目前在电机生产行业相关绿色工厂评价要求缺失的现状,结合我国电机生产企业的物料使用特点、生产工艺特点、生产装备特点、产品特点、能源利用特点、主要污染物排放特点等6个方面,对电机生产企业绿色工厂评价内容、指标及方法进行研究。该研究为我国电机生产行业全面推行绿色制造,加快电机生产行业绿色改造升级,构建电机生产行业绿色制造体系,提高我国电机生产行业的国际竞争力作出积极贡献。  相似文献   
32.
Variations of the ionospheric weather W-index for two midlatitude observatories, namely, Grahamstown and Hermanus, and their conjugate counterpart locations in Africa are studied for a period from October 2010 to December 2011. The observatories are located in the longitude sector, which has consistent magnetic equator and geographic equator so that geomagnetic latitudes of the line of force are very close to the corresponding geographic latitudes providing opportunity to ignore the impact of the difference of the gravitational field and the geomagnetic field at the conjugate points on the ionosphere structure and dynamics. The ionosondes of Grahamstown and Hermanus provide data of the critical frequency (foF2), and Global Ionospheric Maps (GIM) provide the total electron content (TECgps) along the magnetic field line up to the conjugate point in the opposite hemisphere. The global model of the ionosphere, International Reference Ionosphere, extended to the plasmasphere altitude of 20,200 km (IRI-Plas) is used to deliver the F2 layer peak parameters from TECgps at the magnetic conjugate area. The evidence is obtained that the electron gas heated by day and cooled by night at the summer hemisphere as compared with the opposite features in the conjugate winter hemisphere testifies on a reversal of plasma fluxes along the magnetic field line by the solar terminator. The ionospheric weather W-index is derived from NmF2 (related with foF2) and TECgps data. It is found that symmetry of W-index behavior in the magnetic conjugate hemispheres is dominant for the equinoxes when plasma movement along the magnetic line of force is imposed on symmetrical background electron density and electron content. Asymmetry of the ionospheric storm effects is observed for solstices when the plasma diffuse down more slowly into the colder winter hemisphere than into the warmer summer hemisphere inducing either plasma increase (positive phase) or decrease (negative phase of W-index) in the ionospheric and plasmaspheric plasma density.  相似文献   
33.
We present the spatial maps of the ionosphere–plasmasphere slab thickness τ (ratio of the vertical total electron content, TEC, to the F-region peak electron density, NmF2) during the intense ionospheric storms of October–November 2003. The model-assisted technology for estimate of the upper boundary of the ionosphere, hup, from the slab thickness components in the bottomside and topside ionosphere – eliminating the plasmasphere contribution of τ – is applied at latitudes 35° to 70°N and longitudes −10° to 40°E, from the data of 20 observatories of GPS-TEC and ionosonde networks, for selected days and hours of October and November 2003. The daily–hourly values of NmF2, hmF2 and TECgps are used as the constrained parameters for the International Reference Ionosphere extended to the plasmasphere, IRI-Plas, during the ionospheric quiet days, positive and negative storm phases for estimate of τ and hup. Good correlation has been found between the slab thickness and the upper boundary of the ionosphere for the intense ionospheric storms at October–November 2003. During the negative phase of the ionospheric storm, when the ionospheric plasma density is exhausted, the nighttime upper boundary of the ionosphere is greatly uplifted towards the magnetosphere tail, while the daytime upper boundary of the ionosphere is reduced below 500 km over the Earth.  相似文献   
34.
This paper presents traveling ionospheric disturbances (TIDs) observations from GPS measurements over the South African region during the geomagnetically disturbed period of 29–31 October 2003. Two receiver arrays, which were along two distinct longitudinal sectors of about 18°-20° and 27°-28° were used in order to investigate the amplitude, periods and virtual propagation characteristics of the storm induced ionospheric disturbances. The study revealed a large sudden TEC increase on 28 October 2003, the day before the first of the two major storms studied here, that was recorded simultaneously by all the receivers used. This pre-storm enhancement was linked to an X-class solar flare, auroral/magnetospheric activities and vertical plasma drift, based on the behaviour of the geomagnetic storm and auroral indices as well as strong equatorial electrojet. Diurnal trends of the TEC and foF2 measurements revealed that the geomagnetic storm caused a negative ionospheric storm; these parameters were depleted between 29 and 31 October 2003. Large scale traveling ionospheric disturbances were observed on the days of the geomagnetic storms (29 and 31 October 2003), using line-of-sight vertical TEC (vTEC) measurements from individual satellites. Amplitude and dominant periods of these structures varied between 0.08–2.16 TECU, and 1.07–2.13 h respectively. The wave structures were observed to propagate towards the equator with velocities between 587.04 and 1635.09 m/s.  相似文献   
35.
The ionosphere/plasmasphere electron content (PEC) variations during strong geomagnetic storms in November 2004 were estimated by combining of mid-latitude Kharkov incoherent scatter radar observations and GPS TEC data derived from global TEC maps. The comparison between two independent measurements was performed by analysis of the height-temporal distribution for specific location corresponding to the mid-latitudes of Europe. The percentage contribution of PEC to GPS TEC indicated the clear dependence from the time with maximal values (more than 70%) during night-time. During day-time the lesser values (30–45%) were observed for quiet geomagnetic conditions and rather high values of the PEC contribution to GPS TEC (up to 90%) were observed during strong negative storm. These changes can be explained by the competing effects of electric fields and winds, which tend to raise the layer to the region with lower loss rate and movement of the ionospheric plasma to the plasmasphere.  相似文献   
36.
基于Web信息处理的机位信息融合设计与实现   总被引:1,自引:1,他引:0  
基于Web应用逆向工程提出一种网页信息提取的数据融合方案,利用HTTP的POST请求智能获取网页信息,通过自定义串口协议将数据送至服务器,最终采用C#正则表达式提取有效信息,设计在汕头空管站飞行计划处理系统(FIPS)与潮汕机场航班信息查询系统的数据融合中投入实际应用。  相似文献   
37.
当前主流的视频压缩标准,如H.264、HEVC等,主要是针对摄像机拍摄的视频而设计的.而屏幕内容(SC)的视频是由计算机生成的,无噪声,要求更高的压缩效率,同时与摄像机拍摄的视频相比包含更多的结构相似性.提出了一种利用屏幕视频中相似性的模板匹配帧内编码方法,采用由21个像素点组成的模板,以像素点为最小单位对整帧进行模板匹配,并使用哈希函数实现高效的模板查找,最后对残差图像进行熵编码.实验结果显示,与标准的HEVC扩展方法相比,该方法在无损编码上压缩率可以提高一倍,编码时间减小了近一半.   相似文献   
38.
段玉岗  闫晓丰  李超  张小辉 《航空学报》2014,35(4):1173-1180
近年来纤维铺放(AFP)技术被广泛用于大型复杂飞机复合材料构件成型。为了保证纤维铺放过程的一致性,纤维铺放压辊必须在适应芯模型面的同时具有较好的压紧力分布均匀性。鉴于此,对不同弹性模量的压辊材料进行了试验分析,薄膜压力传感器及超声显微镜测试结果表明,低弹性模量的压辊材料变形较大,较好地适应了芯模表面,压力分布相对均匀且可以减少铺层的层间孔隙数量,硅橡胶压辊比聚乙烯压辊压紧力分布均匀性提高了50%~60%,铺层孔隙率降低了92.1%。针对孔隙分布主要集中在压辊两端及压紧力在压辊两端下降幅度较大的问题,采用ANSYS Workbench对压辊端部进行斜端面优化,得到最优倾斜角度为20°;测试结果表明斜端面压辊压力分布均匀性比直断面压辊提高了42.9%,铺层孔隙率下降了51.6%。  相似文献   
39.
The ionospheric total electron content (TEC) in the northern hemispheric equatorial ionization anomaly (EIA) crest region is investigated by using dual-frequency signals of the Global Positioning System (GPS) acquired from Rajkot (Geog. Lat. 22.29°N, Geog. Long. 70.74°E; Geom. Lat. 14.21°N, Geom. Long. 144.90°E), India. The day-to-day variability of EIA characteristics is examined during low solar activity period (F10.7∼83 sfu). It is found that the daily maximum TEC at EIA crest exhibits a day-to-day and strong semi-annual variability. The seasonal anomaly and equinoctial asymmetry in TEC at EIA is found non-existent and weaker, respectively. We found a moderate and positive correlation of daily magnitude of crest, Ic with daily F10.7 and EUV fluxes with a correlation coefficient of 0.43 and 0.33, respectively indicating an existence of a short-term relation between TEC at EIA and the solar radiation even during low solar activity period. The correlation of daily Ic with Dst index is also moderate (r = −0.35), whereas no correlation is found with the daily Kp index (r = 0.14) respectively. We found that the magnitude of EIA crest is moderately correlated with solar flux in all seasons except winter where it is weakly related (0.27). The magnitude of EIA crest is also found highly related with EEJ strength in spring (r = 0.69) and summer (r = 0.65) than autumn (0.5) and winter (r = 0.47), though EEJ is stronger in autumn than spring.  相似文献   
40.
Earthquake prediction stimulates the searches for a correlation between seismic activity and ionospheric anomalies. Contrary to common focuses on strong earthquakes, we report the ionospheric disturbances, 2 days before a moderate Ms = 4.7 Chongqing earthquake (29.4°N, 105.5°E, depth = 7.0 km, occurred at 21:21 LT, 10 September, 2010) with the data of ground-based ionosondes and IGS receivers. The data covering the period under the quiet geomagnetic conditions and a geomagnetic storm was analyzed with upper and lower bounds. It is found that there were significant enhancements of foF2 and total electron content (TEC) on the afternoon of 8 September, 2010, with a limited area close to the epicentre, which was different from the feature of ionospheric perturbations triggered by the geomagnetic storm on 15 September. Taking into account the heliogeomagnetical condition, we conclude that the observed ionospheric enhancements were very likely associated with the forthcoming moderate Chongqing earthquake, which implies that the relationship between the amplitudes of ionospheric disturbances and earthquakes is very complicated.  相似文献   
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