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991.
992.
With the rapid development of Internet, it is increasingly convenient to obtain real-time traffic condition information, which has greatly stimulated the improvement of urban traffic guidance. Traffic conditions are generally divided into four grades in the existing network platform, which are expressed in different colours. The understanding of traffic condition is still at the level of abstract senses. Therefore, it is difficult to grasp the characteristics of urban traffic. To this end, a new idea is proposed in this paper, and the new idea is to study the urban traffic characteristics based on real-time traffic condition information extraction with image identification technology. With this method, we can not only quantify the abstract traffic condition information, but also solve the loss of traffic condition information. In addition, an instance is analysed in this paper, it shows that it can provide references for urban traffic organization management very well. 相似文献
993.
Vivek K. Bajpai Ajay Sharma Kwang‐Hyun Baek 《International Journal of Food Science & Technology》2013,48(11):2300-2305
This study investigated the antibacterial mechanism of action of the seed essential oil of Eleutherococcus senticosus (ESEO) against foodborne pathogenic bacteria. Preliminarily, the ESEO (1000 μg disc?1) showed potential antibacterial effect as diameter of inhibition zones (12.0 ± 0.2–37.0 ± 2.0 mm) against the tested foodborne pathogens. The MIC and MBC values of ESEO against the tested bacteria were found in the range of 125–500 and 500–1000 μg mL?1, respectively. At MIC concentration, the ESEO had potential inhibitory effect on the cell viability of the tested pathogens. In addition, SEM analysis showed the inhibitory effect of ESEO as confirmed by considerable morphological alterations on the cell wall of B. cereus ATCC 13061 and E. coli O157:H7 ATCC 43889. Moreover, the ESEO revealed its mode of action against foodborne pathogens on membrane integrity as confirmed by release of extracellular ATP, 260‐nm absorbing materials and leakage of potassium ions. These findings confirm that the ESEO can be used as a potential antibacterial agent in food industry to inhibit the growth of various foodborne pathogens. 相似文献
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995.
The velocity of an over-burst coal seam is about 1/3 compared to a normal coal seam based on laboratory test results. This
can be considered as a basis to confirm the area of coal and gas burst by seismic exploration technique. Similarly, the simulation
result of the theoretical seismic model shows that there is obvious distinction between over-burst coal and normal coal based
on the coal reflection’s travel-time, energy and frequency. The results from the actual seismic data acquired in the coal
and gas over-burst cases is consistent with that of the laboratory and seismic modeling; that is, in the coal and gas burst
region, seismic reflection travel time is delayed, seismic amplitude is weakened and seismic frequency is reduced. Therefore,
it can be concluded that seismic exploration technique is promising for use in distinguishing coal and gas over-burst regions
based on the variation of seismic reflection travel time, amplitude and frequency.
Supported by the Key Program of National Basic Research Program(973) of China (2006CB202208); the CBM Important Project of
2008ZX05040-003 in China 相似文献
996.
997.
998.
999.
1000.
王文涛 《沈阳工业大学学报》1991,(2)
本文利用活动标架法与Laplacian的特征值方法研究了极小曲面的稳定性。给出了拟常曲率流形中极小曲面的共形度量的高斯曲率之上界估计。证明了拟常曲率流形中极小曲面的一个单连通区域为稳定的一些充分条件。 相似文献