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61.
增强现实已成为全球信息技术产业中最受关注的热点领域之一,目前正处于快速发展时期。便携性、移动性和交互性3大难题,是影响增强现实硬件产品普及的主要因素。基于增强现实硬件产业链研究,通过对比现有AR眼镜参数与全球技术标准,分析了AR眼镜尚待克服的3大难题的根本原因、主要措施及需要突破的技术标准,并展望了AR硬件产业未来的发展方向。 相似文献
62.
提出了一种基于生成对抗网络的无载体信息隐藏方法.发送方用伪装图像和Improved Wasserstein GAN生成一张与秘密图像相同的图像,发送方发送伪装图像,接收方收到伪装图像后用生成器生成和秘密图像视觉上相同的图像.与现有的信息隐藏方法相比,该方法不需要修改载体,能够有效地抵抗隐写分析工具的检测,能够达到秘密信息安全传输的目的. 相似文献
63.
Xueling Shi Tao Chen Lingqian Zhang Suping Duan Jiang Liu Zhaohai He 《科学通报(英文版)》2014,59(34):4790-4796
An ion flux dropout near the dipolarization front (DF) at around XGSM =- 11 RE in the Earth' s plasma sheet was observed by Time History of Events and Macroscale Interaction during substorms (THEMIS) on March 31, 2009. The ion differential energy fluxes at energies from 450 eV to 150 keV measured by the ESA and SST instruments from THC began to decrease about 2 s before the detection of the DF and reached a local minimum 6 s later. Then, the ion fluxes gradually increased to form a dropout around the DF. The spatial extent of the dropout was about 4,000 km. For energies above 20 keV, the ion fluxes after the dropout are greater than those before it, contrary to the fluxes at energies below 20 keV. The associated ion density variation indicates that the ion flux dropout coincides with the ion density dropout. Taking advantage of multipoint observations, THD, THC, and THE detected the same DF consecutively. Only THC detected an obvious ion flux dropout; THD observed an indistinct one about 2 s before THC; no high-energy (E 〉 30 keV) ion flux dropout was observed by THE. Our study suggests that the ion flux dropout may evolve with the earthward-propagating DF, and its properties can depend on locations relative to the DF. 相似文献
64.
For the improvement of accuracy and better fault-tolerant performance, a global position system (GPS)/vision navigation (VISNAV) integrated relative navigation and attitude determination approach is presented for ultra-close spacecraft formation flying. Onboard GPS and VISNAV system are adopted and a federal Kalman filter architecture is used for the total navigation system design. Simulation results indicate that the integrated system can provide a total improvement of relative navigation and attitude estimation performance in accuracy and fault-tolerance. 相似文献
65.
干线协调交叉口多相公交信号优先控制策略 总被引:1,自引:0,他引:1
针对干线协调交叉口多个相位有公交车到达的情况,为降低公交车延误,建立了以不破坏协调绿波带为前提的多相位公交优先控制策略.在该策略中,提出了“就近原则”以解决多个相位的公交优先申请冲突,对公交优先级别进行排序,并建立了多相位公交优先控制流程;考虑最高优先级别公交车的不同相位属性,采用绿灯延长和绿灯提前起亮两种优先方式,分... 相似文献
66.
67.
Coalbed methane (CBM) accumulation models include continuous gas accumulation and staged gas accumulation.However,studied on the geochemical characteristics and indices to evaluate staged accumulation CBM are lacking.This study for the first time obtained the carbon and hydrogen isotopic compositions of methane and ethane generated at different evolution stages using thermal simulation of samples prepared by treating an herbaceous swamp peat at different temperatures.The results showed that the carbon isotopic compositions of methane and ethane were obviously affected by the thermal evolution level of the starting sample,while the hydrogen isotopic compositions were closely related to the maturity of gases.The carbon and hydrogen isotopic compositions of gases generated by coal-forming organic matter with Ro values from 1.2%,1.7%,2.4%,3.2% and 3.7% to 5.2% were determinated.The relationship between Ro values and the carbon and hydrogen isotopic compositions of gases generated by coal-forming organic matter at different evolution stages as well as the carbon or hydrogen isotopic relationships between methane and ethane were established.The results provide a scientific basis for studying the genesis of CBM generated at different maturity intervals and understanding the geochemical characteristics of staged accumulation CBM.These results were applied to a case study on CBM from the southern Qinshui basin,and it was found that the CBM accumulated after the Middle Jurassic and was characteristic of staged gas accumulation.This is consistent with the result of geological studies,and further showed that the results of thermal simulation experiments are very important for evaluating the genesis of natural CBM. 相似文献
68.
火车是目前交通运输能力最强的交通工具之一,火车的运输能力使火车站周边经济能够迅速繁荣起来.如何通过火车站的效益带动周边经济,实现火车站经济圈增长对于我国社会经济具有重要的促进作用.本文在相关理论的基础上,分析了我国现行发展状况下火车站经济圈建设的必要性与意义,同时制定了符合我国实际的发展对策. 相似文献
69.
110kV分段及备投保护屏由四方继保CSC-215母联充电保护装置和CSC-246备用电源投切装置组成.CSC-215保护方面的主要功能有:①短充电流保护、零流保护;②长充电过流、零流保护.CSC-246备投方面的主要功能有:①线路备投方案;②变压器备教方案;③可编程方式制定特殊的备投方式;④备投逻辑中充放电自动完成. 相似文献
70.
在市场经济体制下,招投标管理对公路桥梁施工起到了极大的促进作用,文章从招投标管理的积极作用入手,分析了现阶段招投标管理的一些问题,并提出建议。 相似文献