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1.
针对一点多星系统的特点分析,对同步共位卫星的测控技术进行了初步探讨,给出了高精度扩频测距三站交汇定位和星间链路测量两种解决方法,并初步分析了测量精度和两种方法的比较。  相似文献   

2.
基于高精度24住模数转换芯片AD7750和称重传感器MODEL N0 1004,设计了用于快速称量小计量物品的测量仪。AD7730直接采集称重传感器的模拟信号,单片机接收数据加以处理。由于AD7730的高精度、高抗扰性和称重传感器MODELNO1004的高反应速度,使其这个测量仪分辨率能达到mg级。能够快速测量出重量。  相似文献   

3.
从航天测量系统和数据处理技术着手,探讨了对我国S频段航天测控网的外测系统进行改进的技术途径,提出了在测量体制上的几种改进措施,给出了相应的观测方程,并分析了它们的优越性。  相似文献   

4.
研制了一种高精度的通信卫星测距装置,它采用了数字式测音测距和放大微小传播时间计数的两种新方法。这个装置是一个高精度的卫星轨道观测装置,此外还能作为PCM——TDMA 卫星通信方式的初始目标截获系统,具有两种测量状态,一个是在没有进行 PCM——TDMA 通信时的目标截获状态,另一个是通信时的稳定测量状态。前一种状态的特点是在低信噪比条件下的高精度测量,后一种状态的特点是利用通信信号测量。分辨率为:距离分辨率1米或1毫微秒;径向速度分辨率:1厘米/秒或0.1毫微秒/秒。根据卫星实验证实本装置有上述各种功能,证明如使用本测量方式,则观测点和卫星之间的直线距离测量误差在30米以内。  相似文献   

5.
角位置是深空探测航天器导航定位的重要观测量信息,相对于获取航天器距离、速度信息的统一载波测量体制,甚长基线干涉测量(Very Long Baseline Interferometry,VLBI)技术的原始数据量呈几何式增长,海量数据的实时、准实时处理对航天器高精度导航定位提出了新的挑战。依托中国深空网干涉测量中心,论述了基于高性能集群平台环境的航天器干涉测角数据相关处理系统的设计实现,并利用探月工程的实测数据进行了验证分析。分析结论对推进我国深空网干涉测量信号处理中心建设、优化相关处理系统资源配置具有一定的参考价值。  相似文献   

6.
本文介绍HP8410S刚络分析仪测量介电常数和导磁率的一种应用,所述方法可对介电常数ε~r和导磁率μ_r进行比较高速和高精度的测量,并且方法经济、实用.  相似文献   

7.
魏冰  李娜 《科技转让集锦》2011,(10):142-143
相向开挖隧洞高精度贯通一直以来都是隧洞工程中的重点,作为测量监理工程师,在施工过程中应通过使用联合测量、平行检测等监理手段,监督施工单位的测量质量,达到控制贯通精度的目的,通过引大入连工程隧洞进口与1#支洞贯通的实例,可以看出测量监理工程师在隧洞高精度贯通方面发挥着重要的作用。  相似文献   

8.
为了得到精确的岩体内部变形参数,岩体内部相对位移测量设备的应用已非常广泛,但国内外的位移测量设备相对落后。改变了传统的机械化测量装置,设计出一种自动化、智能化、高精度的位移测量系统。介绍了智能位移测量系统的结构组成、特点及创新点和使用方法。应用函数模拟和数值分析法进行标识点的布置,可为后续的位移测量设备提供参考。  相似文献   

9.
由于频移键控(Frequency-Shift Keying,FSK)体制避障雷达在动目标分辨与测量上的明显优势,基于FSK体制避障雷达系统的基本原理和结构,通过Matlab建立了测量系统与信号模型,使用全相位快速傅里叶变换(All-phase Fast Fourier Transformation,APFFT)算法进行了相关测量仿真和测量参数计算。通过对不同条件下的仿真结果分析,得出了测量结果误差产生的原因,并提出了相应的误差补偿方法,大大降低了测量误差,使得相对误差降低至0.1%以下。另外,还对多目标的分辨与测量进行了仿真。  相似文献   

10.
曹传萌  聂伟 《中国市场》2010,(49):33-34
通过精确确定高精度、高分辨率似大地水准面项目的实施,建立起章丘市高精度的三维大地基础控制网。在GPS日常测量工作中,有了高精度似大地水准面,可用GPS测量取代低等级几何水准测量,真正实现GPS在几何意义上的实时三维定位功能。基于此,文中就我市区域高精度似大地水准面精化项目过程进行了探讨,以供有关单位在精化区域似大地水准面时参考。  相似文献   

11.
The overall strategic relationship between U.K. and China is "better than ever", China- Britain relations have maintained good momentum, with increased high-level exchanges and the reinforcement of strategic mutual trust, with more room for growth in the future.  相似文献   

12.
Domino effects of the global finance agitation As the origin of the subprime crisis,US financial institutions lost USS45 billion last year,accounted for over half of the total US,EU & Japan loss.Since January 15th,Chtigroup released its financial statement of the 4th quarter,showing a net deficit of USS9.83 billion,which marked the hisoric high of its quarterly deficit.  相似文献   

13.
Among the Fortune 500 firms,more and more images from China emerge out.On the 2008 list,Sinosteel Corporation,a landmark group of China industries quietly squeezes into the candidate line.As the largest steel service & trade enterprise,its sales reached at RMB 111.24 billion,with a year-on-year increase of 83.03 percent,and the profit grew by 180.03 percent.On the Sinosteel 2008 Work Meeting,the president Huang Tianwen uttered,"In the coming year,we will work for US$20 billion sales,and look forward to getting a position in Fortune 500 firms for ourselves."  相似文献   

14.
When the 103rd Canton Fair is approaching, an old friend of Canton Fair, Li Ying from Jiangsu prov-ince recollected his past five years' experiences to the grand trade meeting. Each year is special, with some unforgettable memories colored by the year.  相似文献   

15.
Holding 88 percent of train media resources across China, based on "Time Cube", on the 2008 Intermedia Recommendation and Introduction Meeting on December 19, 2007, HTC announced its high-profile strategy of tour marketing and tapping the immeasurable potentials on the train. Meanwhile, HTC officially launched its brand new product Olympic Train on the meeting, providing a fabulous platform for all the brands that are prepared to do a smart marketing on the occasion of 2008 Olympic Games.  相似文献   

16.
In the end of 2007, Air China Limited (hereinafter "Air China") and Shanghai Airlines, formally joined Star Alliance at a ceremony held in the new Terminal Three at Beijing Capital International Airport. With the addition of the two Chinese airlines, Star Alliance now has 19 member carriers operating 17,000 daily flights to 897 destinations in 160 countries.  相似文献   

17.
The annual meeting of the World Economy Forum was held in Davos,a little town in Switzerland,on January 23rd to the 27th this year,with the theme"the Power fo Collaborative Innovation",over 2500 celebrates from ture political and cconomic circles of more than 80 countries and challengred logether to talk about the future of the global economy in 2008,A Forum for the problems and challenges that face whole world,some of the keywords which drew attention during the event were:the U.S.subprime mortgage crisis,soaring energy prices,the economic slowdown in the U.S.ermerging economic bodies,authority funds and the general unpredictable nature of the global economy.  相似文献   

18.
If you are considering to trade with companies in Japan or expanding your .business to Japan, we are ready to help from the very beginning." You will find this greeting at the first sight on the Chinese website of Japan External Trade Organization (JETRO). JETRO has committed itself in delivering highly efficient and quality services to meet the demand of internal and external customs including Japanese companies, hence winning a good reputation in the international trade arena. In recent years, with its priority in advancing business cooperation in South and East Asia, JETRO has made great achievement in promoting trade between China and Japan. Therefore, China's Foreign Trade interviewed Mr. Yoichi Maine, Deputy Director General of JETRO BEIJING.  相似文献   

19.
Looking at the increasingly fierce competition in the world auto market. global automobile manufacturing industry, taking Europe, the U.S. and Japan as representatives, is gradually forming a new type of relationship, mutual cooperation between whole vehicle and parts manufacturers. We can clearly see that auto parts manufacturers have become independent from the whole vehicle manufacturing companies, which means that the former structure of auto industry has greatly changed, and a new relationship,  相似文献   

20.
Estaing, former French president, Valery Giscard d'Estaing attended Sino-French Economic Seminar held in Shanghai in early April and said that the world center has shifted from the west to the east with many European and US companies entering into Asia, and China has the ability to play an important role in the world stage. Estaing, naming himself"French Confucian", then said in Chinese that a cook-group includes 10 people in ancient Chinese soldier system and the cook is in charge of cooking for them. And people who belong to the same cook are actually "Partners".  相似文献   

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