共查询到20条相似文献，搜索用时 31 毫秒
1.
A method of constructing GPS-based positioning services system by means of JAVA technology is introduced in this paper. The position data, which are sent from GPS satellites, are received by GPS receiving terminal and are analyzed by mobile computing client developed on J2ME in accordance with the differential GPS algorithm. The client submits special position querying information to position server in way of wireless GPRS network. After computing and data querying, the server developed by J2EE returns results to the mobile device. Then, the mobile computing client displays the position map or carries out further processing. All of these form a highly precise location-based services system. 相似文献
2.
Presently, ECG monitor encounters the trend of miniaturizing, intelligentizing and networking. Short distance and limited channels are shortcomings of the existed telemetric ECG (Electrocardiograph) monitoring system, while the existed remote monitoring system has the disadvantages of high cost and low Data Transfer Rate. Furthermore, neither of these two systems can implement real-time monitoring on the spot. So, an embedded ECG Monitor based on Linux, which successfully solves these problems, is introduced. With embedded system technique, this embedded monitor, which can not only realize real-time monitoring on the spot, but also analyse the ECG data, has the advantages of low cost, small volume, light weight, low power, high stability, powerful networking function and so on. And by communicating through Internet, which has the features of low cost, high data transfer rate and good expandability, it can also send ECG data to monitoring center in order to achieve long-term monitoring. The development of this monitor provides a new solution for medical instruments' implementation and networking, and is of certain reference value. 相似文献
3.
设计了一个基于ARM技术的粮库嵌入式监测系统.该监测设备由两部分结构组成:一个是上位机电脑控制端对粮食信息的监测和处理,另一个是在下位机实现对粮仓粮食数据的采集,信号的处理以及通讯的功能.通过工业以太网或GPRS网络可以将数据从一方传给另一方.在此基础上展开以S3C2410处理器来实现粮食相关信息监测的研究,其中人机交互界面终端通过Qt/E来设计.试验测试结果证明了该系统的可靠性和稳定性. 相似文献
4.
Based on the analysis of tendency of ICT (information interactive terminal), this paper presents a new embedded terminal which is multifunctional and understandable-MIIT (multifunctional information-interactive terminal based on uClinux) for the disadvantage of ICT, and expatiates the structure and illustration of hardware and software system of MIIT. The paper establishes the application system of MIIT containing the three parts: the collection of data on serial port, the given application program and keyboard, and it also ensures the realization of application system of MIIT and makes MIIT applied in new applications field. 相似文献
5.
Continuous Plant Regeneration from Established Embryogenic Cell Suspension Cultures of Italian Ryegrass and Tall Fescue 总被引：8，自引：0，他引：8
The suitability of different protocols was compared for entire plant regeneration by somatic embryogenesis, of the forage plants Lolium multiflorum Lam. (Italian ryegrass) and Festuca arundinacea Schreb. (tall fescue). In the first protocol, miniature embryos were used as starting material, while mature seeds were retained in the other two. Whichever the considered protocol, undifferentiated calli were produced on Murashige and Skoog MS medium supplemented with 2,4-D. The calli were subcultured in the dark on solid MS agar medium, containing 5 mg/1 2,4-D (protocol 2) or on solid MS medium followed by transfer to a rotated liquid MS medium with 2 mg/1 2,4-D (protocol 1). In these conditions, induction of somatic embryogenesis occurred, and whole plants were regenerated during a limited lapse of time, upon transfer in the light, to MS medium supplemented with BAP but devoid of 2,4-D. The simultaneous elimination of 2,4-D and transfer to light appeared essential for full regeneration of the plants. Using this characteristic, an additional step was added to a new protocol (protocol 3) in which microcalli, cultured on liquid MS medium containing 5 mg/1 2,4-D, were transferred to the same medium with 2 mg/1 2,4-D, in the dark. In these conditions, the suspensions kept their embryogenic potential for months. In all cases, plantlets were successfully transferred into the soil. An evaluation of the somaclonal variation potential of the plants issued from each protocol is now underway. 相似文献
6.
Emerging CATV networks are evolution to Hybrid Fiber/Coax plants. It is widely believed that the HFC network will play an important role in providing broadband accessing service to subscribers due to it's large excess bandwidth and high penetration to the home. Asymmetry broadband data service is the main service provided in the HFC broadband access networks now. It's performance will determine whether the subscribers be satisfied or not and affect the growth of HFC broadband access networks. The authors outline the mechanism of transmitting data in the upstream channel of the HFC network, and analyze how it affecting the performance of data service. The performance of data service and TCP protocol in HFC network is examined. An optimal scheme of bandwidth allocating algorithm for the upstream channel is proposed to enhance the performance of the data service over these networks. 相似文献
7.
Taking the hybrid electric vehicle as the investigation subject, this paper studies the remote data acquisition, supervisory control and redisplay system of the hybrid electric vehicle fault diagnosis. The system gathers the simulate CAN BUS data through serial ports by the data acquisition device and send data to the remote web servers by the GPRS wireless communication module. For the demands and features, the paper makes the module selection and design the hardware of lower computer ,and the software on the host computer and lower computer. It takes several notebooks as the simulate vehicle date emission source to make an experiment, achieving the function of wireless data transfer, data acquisition, supervisory, redisplay for multi hybrid electric vehicles at the same time, and protocol setting up. Especially the function of wireless data transfer and protocol setting up, make a big progress on the common use and convenience of fault diagnosis system. 相似文献
8.
In the system of infrared imaging acquisition, it is necessary to improve data transfer to satisfy the characteristics of high speed and real time. So,this paper introduces PCI bus and PCI inerface to imaging acquisition. The protocol of data transfer of PCI local bus and the structure of PCI9050 are studied in detail, and the IRFPA data acquisition system are described based on the protocol of data transfer of PCI local bus. The system adopts frame buffer to make slow transmission between peripheral circuit and PCI bus.CPLD is also used as a master of logic time control? 相似文献
9.
Transmission Control Protocol(TCP) is tuned to perform well in wired networks or environment with low bit errors where packet losses occur mostly because of congestion.However,when TC Pis operated in high BER environment and suffers from significant losses due to bit errors,it does not make the best use of the available bandwidth of links because TC Phavles its current congestion window blindly.As a result,the performance of TC Pwould be deteriorated very much.Recently,the use of enhanced bandwidth estimation procedures within the congestion control scheme of TC Pwas proposed as a way of improving TC Pperformance over links affected by random loss.This paper first analyzes the problems faced by every bandwidth estimation algorithm implemented at the sender side of a TCP connection.Some proposed estimation algorithms,accuracy and performance are estimated.At the same time,the authors discuss the relationshi Pbetweent the bandwidth estimation accuracy and the fairness of protocol.Finally,this paper point out the further work should be done in future. 相似文献
10.
An extended function of SOCKS firewall that enables smooth heterogeneous communications between the IPv4 nodes and IPv6 nodes based on the SOCKSv5 protocol is introduced, the architecture of translating IPv4 and IPv6 by applying the SOCKSv5 protocol is presented, there are two models of translating IPv4/IPv6 techniques and its mechanism, principle are more illustrated in details, an example for a SOCKS client securely transparent accessing to remote destination computer with different IP addresses is discussed. As well as the techniques of Direct Address Translation and DNS Name Resolving Delegation are developed , which it keeps the old SOCKSv5 firewalls' advantages, and shows another new characteristics. Therefore, the new firewalls technology are presented much wider application fields. 相似文献
11.
棉花对初蕾期物理伤害的调节补偿效应 总被引：1，自引：0，他引：1
黄河流域棉区棉花在蕾期常遭遇冰雹所致的物理伤害,但棉花具有一定的调节补偿能力。明确棉花对不同程度物理伤害的补偿效应,对灾后棉田管理具有指导意义。以山东主栽棉花品种K836为材料,于2014—2015年棉花现蕾后第5天在山东省临清市设置去顶去叶(RTL)、去顶留1叶(RT+1LM)、去顶留叶(RT+ALM)、留顶去叶(TM+RL)、留顶留1叶(TM+1LM)以及未损伤的正常植株(CK) 6个处理,研究不同程度损伤对棉花生长发育、叶面积动态、净光合速率、生物量、棉柴比、产量及产量构成的影响。结果表明,对于棉花单株干物质量, TM+1LM处理在15 DAT和30DAT(物理伤害后天数)分别比CK降低59.0%和12.1%,但在45DAT和60DAT与CK无差异;其余伤害处理在15～60 DAT均不同程度降低。叶面积指数变化动态与干物质积累趋势一致。处理45 DAT内, RTL、RT+1LM、RT+ALM和TM+RL的净光合速率均低于对照,且高峰值出现时间推迟, TM+1LM的净光合速率变化趋势及高峰值出现时间与对照一致。TM+RL生物产量较CK降低18.2%,而RTL、RT+1LM、RT+ALM和TM+1LM的生物产量与CK相当; RTL、RT+1LM、RT+ALM和TM+RL的棉柴比分别比CK降低52.6%、47.3%、36.8%和23.7%,而TM+1LM的棉柴比与CK无明显差异。RTL、RT+1LM、RT+ALM和TM+RL单位面积铃数分别减少19.0%、7.2%、9.9%和15.6%,单铃重分别降低23.2%、8.9%、8.9%和19.6%,籽棉产量分别降低36.3%、17.5%、15.5%和31.9%,而TM+1LM的铃数和单铃重没有显著降低,籽棉产量与CK相当。据此,把蕾期物理损伤分为轻度损伤(TM+1LM)、中度损伤(RT+1LM、RT+ALM)和重度损伤(RTL、TM+RL),其减产幅度分别在5%以内、15%左右和30%以上。对于轻度和中度损伤棉田,宜加强水肥管理促进棉花补偿性生长,减少产量损失;对于重度损伤棉田,可以考虑改种其他短季作物。 相似文献
12.
G. A. Slafer 《Journal of Agronomy and Crop Science》1995,175(4):249-263
A wheat cultivar (Condor) was grown in two experiments (thermal regimes 18/13 and 21/16°C) under low (298 μE m-2: s-1) radiation regimes during either an early phase from seedling emergence to terminal spikelet initiation (S2), a late phase from terminal spikelet initiation to anthesis (S2), or for the full period from seedling emergence to anthesis (S12), or high (560 μE m-2s-1) radiation throughout the growing period (S12) to determine whether developmental events are affected by radiation. The main developmental events considered in this study were the timing of terminal spikelet initiation and anthesis, the final number of leaf and spikelet primordia initiated in the apex and the rate of leaf appearance. Number of grains per spike and culm height were also measured. The duration of each phenophase was not affected by radiation intensity. Temperature affected the rate of wheat development, but the acceleration of development due to temperature during the seedling emergence - terminal spikelet initiation phase only slightly reduced (from 24.8 to 23.2 days). Differences in time from terminal spikelet initiation to anthesis were greater than in the earlier phases, having been the duration reduced from 24.6 to 20.0 days due to high temperature. Associated with the lack of effect of radiation on phasic development and the negligible effect of temperature on the duration of the early phases of development, final Leaf number was practically unchanged in this study by either the radiation level or the growing temperature. Thus, radiation did not affect the rate of leaf initiation. The number of spikelets was affected by neither the treatments nor the thermal environment. The rates of leaf appearance were accelerated by temperature. Radiation, on the other hand, did not significantly alter the rates of leaf appearance in any of the treatments. As expected from many sources in the literature, the number of grains per spike was significantly affected by radiation during the phase from terminal spikelet initiation to anthesis. Due to the lack of significant effects of radiation on the developmental patterns of wheat, the changes in number of grains per spike were due to changes in the number of grains born in each spikelet. The results of the present study were compared with others available in the literature on the effects (or lack of them) of radiation and CO2 concentration on phasic development, plastochron and phyllochron in wheat to reach the general conclusion that the rate of developmental events in wheat, in contrast to other plants, is almost completely independent of the availability of assimilates, with a possible exception for the Equatorial latitudes. 相似文献
13.
基于XMPP的农业远程监测和诊断平台的研究 总被引：2，自引：1，他引：1
为解决农业生产远程监测和远程咨询诊断问题,采用XMPP及其扩展协议Jingle,研发农业远程监测和咨询诊断于一体的综合平台,实现农业生产环境因子远程监测、生产现场远程视频监视和远程双向视频咨询诊断功能。平台采用客户端和服务器结,农业生产环境因子远程监测依靠集中器把各指令和数据转换成XMPP格式,生产现场远程视频监视和远程双向视频咨询诊断通过XMPP解析模块把各指令和文本数据转换成XMPP格式,然后与服务器端进行通讯,音频和视频数据采用XMPP的扩展协议Jingle进行传输。平台在农产品安全生产中进行了试用,农业生产远程监测和专家咨询诊断在同一平台完成,保证了农作物生产的产量和品质。 相似文献
14.
The paper mainly analyzes and studies mode of bus communication based on optical fiber at one_point to multiple_point and mode of point_to_point communication based on wireless at one_point to multiple_point. The advantages and disadvantages of two communication modes are given. Considering the demands on FA data communication,the paper presents transmitting data based on network mode and connection mode,implementing application protocol based on object oriented mode and international standard. Considering the requirements of FTU unit for data communication, the paper proposes the network inner operating system in FTU unit, which is indispensable. Data are transmitted on client/server mode, defined and organized on object oriented mode and transmitted on logical address. 相似文献
15.
An electrocardiogram (ECG) is an essential way for diagnosing the heart disease, and the test theories and systems work well with the practice application, whereas, as new technologies and devices come forth one after another, it allow us to acquire the ECG data more conveniently, more accurately, more comprehensively. The authors discuss the design of ECG data acquisition system based on the USB 2.0 protocol, and expatiates the system principle in detail. The system employs two AD73360 to sample the standard 12-lead signal simultaneously, which has a resolution of 16-bit. They utilize EZ-USB FX-2 as the USB interface device, which can transfer the data conveniently and quickly, and also permit the configuration of multi-system controlled by just one host. Considering the DSP as a powerful tool in the field of digital signal processing, ADSP-2181 has been chosen. 相似文献
16.
农产品远程价格信息采集和发布系统的研究 总被引：1，自引：0，他引：1
利用TC35与低功耗单片机结合设计便携式手持数据采集终端,采用手持信息采集终端收集信息,通过GSM方式传送到数据中心,数据中心负责处理和发布信息,实现了农产品远程价格信息的采集和发布,用户可通过上网或手机短信进行价格查询。系统实时性好,可靠性高,克服了以往信息采集发布的缺点,能够有效的进行农产品价格信息方面的信息传递工作及数据统计。详细阐述了手机模块TC35中SMS功能的工作原理、便携式手持终端的硬件设计与软件实现。经示范应用,系统达到了设计目标。 相似文献
17.
This paper develops a vehicle carried remote data acquisition terminal based on GPS/GPRS integrated DTU(data transfer unit) and CAN Bus data acquisition module, and built a parameter remote monitoring system of HEV with GPRS and Internet. By using PIC18F4580 with built in CAN control module and industrial DTU MD610G, we transmitted the parameter data and GPS information of the HEV(Hybrid Electric Vehicle) terminals to the remote data control center through GPRS(General Packet Radio Service) and INTERNET. Taking VC++ as the development tool, we programmed a monitoring software of data exchanging, data processing and monitoring. The software also has the function of CANoe data playbacking and strengthened the system versatility. Eventually, the parameter remote monitoring system of HEV is developed. The experiment results show that the system works well. 相似文献
18.
19.
In the process of breeding triploid hop cultivars, diploid varieties need to be raised to the tetraploid level. Existing methods are predominantly based on treatment of the apices with antimitotic substances, in vivo or in vitro , resulting in a reported maximum of 26% tetraploids and a large proportion (over 60%) of mixoploids. This study was set-up to test whether an adventitious shoot regeneration protocol can be used as an alternative. In the first part of the experiments, regeneration media and a choice of explants (internodes, petioles and leaf discs) were optimized using three hop cultivars with putatively low, medium or high adventitious shoot regeneration capacity. On an optimized induction medium supplemented with 6 mg/l N 6 -(2-isopentenyl) adenine (2iP), a regeneration rate up to 17.7% was obtained from cultured internodes, even of the most recalcitrant 'Aurora', while the regeneration rate of the most responsive 'Tettnanger' was 56.9%. Flow cytometric analysis of ploidy level revealed a high frequency of tetraploid induction, the highest (58.6%) being in 'Savinjski golding'. In 616 regenerants of all three cultivars, 30.4% were found to be tetraploid, the others were diploid. Cytokinin content was found to be of minor importance in tetraploid induction. The high frequency of spontaneous tetraploid induction and, in particular, the complete absence of mixoploids makes this protocol an alternative to the currently established methods of chromosome doubling based on the use of antimitotic substances. The occurrence of a high proportion of tetraploid adventitious regenerants in hop is discussed in view of certain other biotechnological applications. 相似文献
20.
嵌入式GIS技术在农业上的应用 总被引：1，自引：1，他引：0
嵌入式 GIS是 GIS发展的方向之一, 嵌入式 GIS在农业上的应用促进了农业信息技术的大众化应用。为了发挥嵌入式 GIS在农业上的积极作用, 介绍了嵌入式 GIS的技术体系、 农业嵌入式 GIS的发展现状和农业嵌入式 GIS应用开发的技术路线, 以 Android平台的嵌入式施肥系统展示农业嵌入 GIS应用的功能。嵌入式 GIS随着移动终端和操作系统的更新及用户需求更多样化、 简单化, 在农业信息化方面有重要作用, 实现农业的现代化和可持续发展。 相似文献