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21.
Agriculture-based precise and accurate information needs to be disseminated promptly to farmers so that better decisions such as managing farm fields, making continuous and scientific changes in their production systems and grabbing advantage of market opportunities can be made. In this paper, mobile technology is assessed for the agriculture information dissemination system. A survey has been conducted to find out potential technology, related to the use of the Internet and mobile among farmers in the state of Punjab in India, to deliver agriculture-related information to them. Results show that agricultural information system needs to be developed based on the mass communication technology such as mobile systems. It is also noted that localization and native language of farmers are the concerns to be incorporated into the systems. It has been focused that the use of soft-computing techniques in conjunction with communication networks, for inferring the decision regarding best practices for agricultural activities, is helpful in the development of these systems. 相似文献
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黑龙江某低品位铜钼矿平均含Mo 0.026%,含Cu 0.015%,属低品位矿。由于矿石含钼、铜较低,为降低选矿成本,有效回收有价金属,对矿石进行详细的工艺矿物学研究。研究发现,主要金属硫化矿有辉钼矿、黄铜矿、黄铁矿、磁黄铁矿等,主要脉石矿物有钾长石、斜长石、石英等。辉钼矿主体嵌布粒度在0.01~0.5 mm,约49.44%,属于微细粒级-细粒级嵌布。黄铜矿主体嵌布粒度在0.02~0.25 mm,多属于微细粒-细粒级嵌布。此外辉钼矿与黄铜矿彼此共生关系密切、黄铜矿可浮性好,造成铜钼分离困难。根据工艺矿物学研究结果,建议采用“快浮+粗选”工艺流程,钼精选强化对黄铜矿的抑制,并增加精扫选作业,有效降低了钼精矿中铜的含量,且实现了铜的综合利用。 相似文献
24.
D2D (device-to-device)通信是5G网络中的重要技术,有利于提升数据分发业务传输效率;然而,由于D2D通信引入了大量额外信令开销,当前的增强多播方案无法解决高效数据传输与低效信令流程之间的矛盾,降低了整体性能增益.为此,提出了一种基于多维矢量分析的最小化信令开销的D2D簇内信息共享算法,包含集中式与分布式两种实现方式,能通过自适应地选择D2D多播重传发射者和多播重传数据分组,大幅减少簇内重传次数,达到显著降低信令开销和传输时延的目的. 相似文献
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为更好地对待发布数据进行隐私保护,构建综合k-匿名、l-多样性和t-闭合方法的匿名化隐私保护模型.利用该模型能够选择最适合的隐私保护方法,并优选对应的隐私保护参数,达到数据提供者所期望的隐私保护效果,满足数据使用者对可用性的要求.实验结果表明,该方法不仅可以找到相对较优的参数值,而且能够有效满足具有不同身份和应用需求的... 相似文献
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《国际互联网参考资料服务季刊》2013,18(2):21-29
ABSTRACT Current awareness is something that librarians do, at least informally, passing on relevant current information to their patrons on a regular basis. The type of current awareness service considered here entails running preselected searches against electronic databases. The availability of these electronic bibliographic databases allows automating much of the current awareness process. Any successful current awareness service will have three key attributes: speed, ease of use, and relevance. The flexibility and accessibility of the National Library of Medicine's PubMed make it ideal as the basis for a current awareness service. Six freely available services are evaluated according to uniform criteria with notes made of special features. Four services use PubMed as the source for data, and the other two use MEDLINE. Recommendations are made for modifying one of the services to embody the key attributes of a successful service. Particular attention is given to local needs. Such a service can be run from a single desktop machine with a dial-up connection to the Internet. 相似文献
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在选矿试验研究的基础上,结合对蚀变岩、花岗岩及石英脉等类型辉钼矿的工艺矿物学特征考察,分析了矿石类型、嵌布特征和矿粒粒度等与其选矿指标的关系。研究表明,辉钼矿的选矿指标与其矿粒粒度关系密切,随着辉钼矿矿粒面积累计含量的增加,其选矿指标提高明显。本研究的开展,将为全面开展典型矿产资源工艺矿物学特征调查,运用现代测试分析技术(如MLA等),快速分析矿物嵌布粒度、分布状态等矿石特征,研究总结其与选矿工艺指标关系,建立矿产资源节约与综合利用评价指标体系,实现矿产资源合理开发利用评价,为促进矿产资源节约与综合利用管理奠定基础。 相似文献
28.
Yong Li Li Qiu Depeng Jin Li Su Pan Hui Lieguang Zeng 《Wireless Communications and Mobile Computing》2015,15(3):527-537
Groups of people with mobile phones using short‐range connections such as WiFi and Bluetooth to propagate messages can be modeled as, with regard to regular absence of end‐to‐end connection, mobile social networks (MSNs), which can be exploited to offload a significant amount of mobile content from the overloaded infrastructure networks such as 3G. The study of content transmission delay for the applications of mobile content dissemination in MSNs is an important problem, because to enhance the network capacity, the traffic is offloaded at the cost of inducing longer delay. In contrast to existing works, which ignore the factors of contact duration limits and large content size, we present a contact duration aware framework to model the content dissemination process in MSNs, give an explicit expression for the average content dissemination delay, and reveals its relationship with various system parameters of content size, users’ selfishness, number of involved subscribers, infecting ratio, and so on. We apply our proposed model to real‐life traces to assess its reliability by comparing the theoretical results with measured statistics and present extensive upshots to evaluate the influence of various parameters on system performance. The results demonstrate the accuracy of our proposed framework and reveal that system parameters of content size, system infecting ratio and intragroup transmission are the most important factors to influence the content dissemination delay. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
29.
本文由“审美信息”概念入手,从信息传播的角度,从审美的主客体一人和建筑两方面,对建筑装饰在建筑审美信息,也即建筑的精神文化传播中的价值进行主要论述,强调建筑装饰的传播功能以及其传达建筑精神、文化的价值功能。 相似文献
30.
《金属学报(英文版)》2014,(5)
<正>Copyright Information For Authors As soon as an article is accepted for publication,authors will be requested to assign copyright of the article(or to grant exclusive publication and dissemination rights)to the publisher(respective the owner if other than Springer).This will ensure the widest possible protection and dissemination of information under copyright laws.More information about copyright regulations for this journal is available at 相似文献