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1.
为了实现小动物PET系统数据高速传输的可靠性,采用TCP/IP协议对数据进行传输模拟.通过分析客户端/服务器模式控制数据的发送与接收,优化了客户端的处理能力,响应时间快;降低了系统的通讯开销,提高数据传输的安全性与可靠性.  相似文献   

2.
为加强当前高校宿舍安全的监控和管理,设计了基于ZigBee和3G技术的高校安全监控系统的解决方案,实现了宿舍环境数据上传与后台监控中心数据接收的实时同步.系统参照物联网理论模型设计,包括感知层、网络层和应用层3个部分组成.感知层利用ZigBee和传感器技术组建无线传感器网络,负责采集宿舍环境相关数据;网络层利用ARM-3G嵌入式网关将感知层数据上传至后台服务器;应用层则利用PC客户端和手机应用程序组成后台监控中心,负责数据的监控和管理.模拟测试结果表明,上位机软件实时接收数据后,工作人员能根据数据做出相应的处理.整个系统运行稳定,达到了预期的设计要求.  相似文献   

3.
局域网中的课件内容标引与主动服务   总被引:2,自引:1,他引:2  
为实现资源的有效共享,分析研究了教育网格中的信息标引与统一内容定位技术,给出了在局域网中课件内容标引与主动服务的实现方案。由教育课件标引框架确定其标引元素,用ACCESS生成多课件的标引信息表,采用 MFC编程平台和TCP协议,在LAN环境下实现服务器端被动发送、客户端主动接收。  相似文献   

4.
基于LabVIEW平台开发出的局域网灯光控制系统,包括灯光控制服务端和灯光控制客户端。灯光控制客户端通过TCP/IP协议向灯光控制服务端发送灯光控制命令,灯光控制服务端接收到灯光控制命令后对系统的灯光进行开关、亮度和使用时间的调节,并对灯光使用过程中的用电量进行实时记录.通过设置不同的数据传输端口,实现灯光控制客户端和灯光控制服务端之间一对多的控制,实现远程控制端同时对多个区域进行灯光控制。该系统可以广泛运用于家庭、学校、工厂、企业的灯光控制中,系统运行过程无需任何数据传输费用,系统运行稳定高效,性价比高。  相似文献   

5.
针对水质环境的检测难以实时传输的问题,设计了一套基于微控制器STM32的水质检测系统.该系统分为上位机和下位机两部分,下位机实时检测发送,上位机接收并处理数据.系统中加入pH值检测模块、DS18B20温度传感器模块和TDS水质检测模块,可以实时检测水的pH值、水温和TDS水质,结合相应的Web客户端、手机APP远程无线收发,可以提高检测效率.  相似文献   

6.
针对水质环境的检测难以实时传输的问题,设计了一套基于微控制器STM32的水质检测系统.该系统分为上位机和下位机两部分,下位机实时检测发送,上位机接收并处理数据.系统中加入pH值检测模块、DS18B20温度传感器模块和TDS水质检测模块,可以实时检测水的pH值、水温和TDS水质,结合相应的Web客户端、手机APP远程无线收发,可以提高检测效率.  相似文献   

7.
基于FPGA的以太网MAC子层协议设计实现   总被引:6,自引:0,他引:6  
介绍了基于现场可编程门阵列(FPGA)的以太网MAC子层协议的硬件实现方法。硬件结构上由控制模块、发送模块和接收模块3个部分组成,发送模块和接收模块采用状态机控制数据发送和接收的过程,完成数据的封装、发送和接收功能。  相似文献   

8.
基于SIP的视频监控服务器设计   总被引:3,自引:0,他引:3  
设计和实现了一个基于SIP的视频监控系统,将会话发起协议(SIP)用于视频监控系统的信令控制,并对构成系统的两个主要组成部分:视频服务器和客户端做了介绍.视频服务器采用ARM+DSP的双核处理器结构,完成了音视频数据的采集、编码、压缩和网络传输等任务;客户端采用Windows平台开发,主要实现音视频数据的接收、管理、存储和提供用户对数据的访问界面等功能.双方的信令控制部分采用SIP协议实现,阐明了其设计思路及实现方法.  相似文献   

9.
基于IOCP的放射源自动监控系统   总被引:2,自引:0,他引:2  
针对放射源自动监控系统无线数据传输的特点,提出了基于IOCP(I/O完成端口)的数据通信模型,该模型只采用较少的线程接收客户端发来的数据,并采用异步消息处理机制,可以将数据接收和处理过程分解开来,从而快速响应其他客户端的数据请求,因此可以大幅提升数据接收服务器的工作性,有效避免了基于传统Socket设计的数据通信模型占用服务器系统资源多、并发处理能力不足等缺陷.介绍了基于IOCP的放射源自动监控系统的结构特点及工作方式.  相似文献   

10.
MAC802.11 协议被广泛应用到无线 Ad Hoc 网络中,在 MAC802.11 协议下的无线 Ad Hoc 网络中,针对两个邻近的发送节点之间、两个邻近的接收节点之间的吞吐量否会相互影响的问题进行研究.根据 MAC802.11 机制进行分析,理论分析与仿真实验都表明表明:当某一节点的邻居节点发送或接收时,该节点的吞吐量会因为受到邻居节点的影响而降低.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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