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31.
结合5G基站建设数据定量分析了重庆市5G网络建设进展,并通过5G频率使用率测试分析了重庆市5G网络使用现状,客观反映了当前5G网络使用特点以及覆盖发展规律。同时,分析了重庆市5G发展存在的主要问题,并针对性提出了发展的措施建议,对于加快重庆市5G网络发展、抢占5G产业发展制高点具有一定参考意义。  相似文献   
32.
介绍了美军频谱管理机构及职责,并从频谱的规划管理、用频管理以及频谱管理的系统和工具等方面阐述了美军的频谱管理体系.  相似文献   
33.
The needs of long-term care (LTC) have increased substantially worldwide. In particular, Taiwanese society has experienced an increasing aging population because of the sharp decline in the birth rate and advanced medical technology. Some LTC facilities have introduced information technologies to satisfy the substantial demand. Compared with the high level of informatization observed at Taiwanese hospitals, LTC facilities still exhibit low informatization levels despite belonging to the same industry. Therefore, this study evaluated the system use performance and continued use intentions of the long-term care information system (LTCIS) by applying the well-known theories of the task-technology fit, system satisfaction, and postacceptance continuance models used in information systems area. The results showed that users’ assessment of whether the LTCIS fulfilled their work and task needs primarily depended on the system quality, locatability of data, timeliness, ease of use, and system-user relationship. These factors also exerted a crucial influence on system use performance and user satisfaction. Moreover, the system use performance and user satisfaction further affected intentions of continued use.  相似文献   
34.
选播通信提供了一种从一组具有相同选播地址的服务中选取最佳服务的机制。在研究选播通信服务模型的基础上利用改进的遗传算法实现了有QoS保证的选播路由,并进一步优化了网络的资源利用。仿真结果表明,这种算法是有效且可行的。  相似文献   
35.
战友  梁祥  孙国君 《煤炭技术》2000,19(5):51-51
:分析了矿井水的产生及七台河矿区矿井水的特点 ;论述了矿井水的治理办法和产生的社会效益  相似文献   
36.
The amounts of N and K fertilizers used in the South African sugar industry have increased dramatically in the past four decades, due partly to an increase in the area under sugarcane but also to large increases in the amounts of N and K fertilizers applied per hectare. There has also been an increase in the amount of P fertilizer used but this has been more gradual. The main fertilizer carriers for cane and their relative efficiency are discussed. During this period there has been considerable research into the nutrient requirements of sugarcane. Correlations established between soil and leaf analysis and crop responses to N, P and K fertilizers, and their effects on cane quality, are reviewed. While fertilizer recommendations based on soil and leaf analysis have provided a useful guide for determining the nutrient requirements of cane, they are continually being modified in the light of current research.  相似文献   
37.
我国是煤炭生产大国和消费大国,梳理和总结国内外有关煤矿区土地生态系统碳源/汇研究,对于我国碳达峰和碳中和目标的实现具有重要意义.本文综述了矿区碳源/汇构成、损毁土地生态系统碳排放、复垦土地生态系统碳固存及矿区减排增汇途径.研究结果表明:矿区碳源包括植被破坏、土壤质地变化产生的碳损失和开采中化石能源使用产生的碳排放,碳汇...  相似文献   
38.
Risk perceptions and technology innovativeness are the two primary factors related to the adoption of mobile technologies. The current study examines the role of technology innovativeness and risk perceptions on smartphone use and dependence in an Asian context. A total of 9086 participants were recruited through online surveys from ten Asian countries. Ordinary least squares regression analyses revealed the effects of technology innovativeness, information security, privacy concern, and their interactions on smartphone use and dependence. Moreover, based on users’ smartphone usage patterns and perceptions, this paper identified four homogeneous groups using cluster analysis. Results shows that Asian smartphone users can be segmented into four groups: innovators, conservatives, moderators, and laggards. The four clusters show significant differences in demographic features. Theoretical and practical implications are discussed based on these findings.  相似文献   
39.
The recent trend of aging population, not to mention the unprecedented pandemic, draws great attention from the general public about health concerns. Since healthcare information technology is different from non-healthcare information technology, additional contexts should be properly incorporated into technology acceptance research to accurately identify influential factors affecting the acceptance of wearable healthcare technology. Thus, we selectively reconfigured factors from health, privacy, and socio-demographic contexts to formulate a health-aware acceptance model. Then, it was empirically analyzed using structural equation modeling. Based on the results, whereas privacy concerns were directly associated with intention to use wearable healthcare technology, health concerns were not. Moreover, age had a moderating effect on social influence and facilitating conditions. These findings suggest valuable insights that the adoption rate of healthcare technology is increased by 1) keeping personal information securely, 2) facilitating social interaction among users, and 3) offering intuitive user experience for elderly people.  相似文献   
40.
黄剑祎 《电视技术》2015,39(12):12-15
为切实推进省级安全播出调度指挥工作的信息化、网络化建设,进一步提高调度指挥效能,按照上级总体部署,结合省级具体情况,设计并建成了省级广播电视安全播出调度指挥平台工程.该工程的设计秉承安全、稳定、实用、经济的原则,充分采用当今尖端的计算机编程技术,将公告发布、数据传输、预警信息发送及视音频通信功能融为一体,并利用先进的网络集成和数字通信手段,通过光纤和SDH环网等设施将网络延伸至省局属各有关单位值班机房,既实现了安全播出信息资源共享和调度指挥指令第一时间到达播出第一线,又为安全播出事件事故的应急处置工作提供了便捷高效的平台.  相似文献   
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