共查询到18条相似文献,搜索用时 437 毫秒
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FMIOiSi-Ⅰ固态调频发射机具有低运行成、工作性能稳定、低停播率、功放模块使用期限长和发射机维护量轻等优点,在县级广播电视转播台得到了较为普遍的应用一本文简述了该型号发射机原理及日常维护方法,并对功放一些故障进行简要的分析。 相似文献
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我国目前没有自主研制的数据链应用获得适航认证。从怎样获取适航认证的角度,介绍了联邦航空局(FAA)颁布的咨询通告(AC)中推荐的可用于申请民机适航型号合格证(TC)的民机数据链应用,总结分析了国外民机数据链应用发展趋势及应用现状,结合我国国情,提出了可用于申请中国民用航空总局(CAAC)及联邦航空局(FAA)适航型号合格证(TC)的民机数据链应用实现建议,为我国民机数据链应用的研发提供适航认证途径的借鉴和参考。 相似文献
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网络经济条件下,大量的数据都可以被记录和追踪,对统计工作而言有极大的促进,不仅能够提高数据的准确性和完整性,还可以实现追溯。但同时,网络中的电子数据容易被修改,在意外发生时极易丢失。因此,基于网络的统计工作必须提高数据管道的把控和安全的维护。本文首先分析了现有统计制度和方法的特点及不足。并介绍了网络环境下统计工作的对象,工具及方法的变化。最后从技术和制度两个大方便探寻新时期统计工作的方法。 相似文献
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现阶段,高级水果质量追溯系统存在系统结构中心化,数据易篡改,数据的安全性、完整性难以保证等问题。这些问题的解决得益于区块链技术的出现。区块链技术的去中心化、开放性、不可篡改性等特点能够有效地解决现存的问题,对打击假冒伪劣,追溯质量安全,维护消费者权益起到积极作用。 相似文献
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分析大数据技术的应用特点,通过Map-Reduce模型、NoSQL和Key-value存储等相关理论的分析,设计大数据副本服务器的Hash-map分布方案,针对精准化营销等特定应用,解决数据一致性检索的追溯性问题。研究认为:(1)大数据的Key-value弱化了数据间的关联关系,建立追溯性索引的弥补机制是必要的;(2)Hashmap索引能够通过(key,value)映射关系对精准化营销产生重要影响;(3)精准化营销可以拉动客户价值的提升,创新因子与限定因子的辨证关系,对保持网络生态系统的平衡起着关键作用。 相似文献
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进行设备级的安全性评估是民用客机VHF通信电台适航审定的要求。简述了机
载系统和设备的安全性评估指南、方法及过程,描述了VHF通信电台各组成模块的失效
模式及失效率,并运用SAE ARP 4761所推荐的故障树方法估算出了单通道架构VHF通信电
台的失效概率,估算结果说明单通道架构VHF通信电台不能满足飞机级PSSA(Preliminary S
ystem Safety Assessment)分配的失效概率要求。最后,为了降低VHF通信电台的失效概率
,提出了VHF通信电台的非相似多通道实现架构。分析表明,与单通道架构相比,非相似多
通道实现架构的VHF通信电台具有更低的失效概率。 相似文献
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URSULA KRISCHE 《International journal of injury control and safety promotion》2013,20(3):119-128
Abstract Many countries have implemented safety and performance requirements for children's products. There is, however, a need to harmonize existing legislation and standards to facilitate a uniform flow of trade. At the same time, it is essential to extend existing requirements to restrict certain hazards which have not been covered in the past. In CEN, the European Committee for standardization, several technical committees are developing European Standards for products to be used by or for children. On a global level as well, within ISO, there are standardization projects covering such products. Child safety is the main objective for the standardization work on: ?Safety of toys (CENATC 52, ISO/TC 181) ? Child use and care articles (CEN/TC 252) ?Playground equipment for children LCEN/TC 136/SC 1) ? Children's furniture (CEN/TC 207, ISO/TC 136( ?Child-resistant packaging (CEN/TC 261/SC 2, ISO/TC 122) Children's products constitute a group of consumer products with large variations between the different products. Nevertheless, since they all come in contact with children (and their parents), several hazards associated with these products are similar for the various products. This is reflected in the work of CEN/TC 252, Child use and care articles, established in 1990. To establish a horizontal framework for the hazard-based approach, CEN/ TC 252 created a working group with the task to specify general and common safety requirements (WG 6). Five working groups started the elaboration of product standards in parallel. The traditional concept of a standardization project was found inadequate and other solutions were sought. Finally, it was decided to combine the results from working group 6 into one guidance document, to be published as a CEN Report. 相似文献
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Melur Sukumar Gautham Kavya Nadig Anaurene Roy Lakshmi Nair 《International journal of injury control and safety promotion》2020,27(3):336-346
Abstract Ensuring optimum safety in schools to prevent injuries and promote safety of children is a mandate by the Constitution of India. However, there is limited evidence regarding safety and injury prevention in schools. This safety appraisal was conducted on a sample of 131 schools, selected by stratified random sampling in Bengaluru and Kolar districts in India. Trained investigators collected data using smart phone-assisted interview, observational methods and record review between 1 January and 31 March 2019. Safety was assessed across the domains of macro areas (policy, guidelines, committee, budget, coordination and training), physical infrastructure, road and transport safety, fire safety and first-aid services. Safety level (%) at each school was computed based on scores obtained in each domain. Overall safety level was at 50.8% of the assessment criteria and was relatively better in private schools (54%). Most schools scored less than 30% in domains of transport safety, fire safety and macro areas. Results highlight the need for implementing and augmenting safety measures in schools. 相似文献
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首先构建了消费者对认证食品的消费行为理论模型,然后在对消费者进行问卷调查的基础上,探讨了消费者对检测与认证机构信任的维度,采用多元回归方法分析最终变量对认证食品购买意愿的影响。结果表明,消费者对检测与认证机构的信任能够提高对认证食品的购买意愿,增强消费者对检测与认证机构的信任应做好三方面工作:加强检测与认证机构的食品检测与监督能力并提高认证人员业务素质;加强对检测与认证机构的监督和提高检测与认证机构工作的诚信度;加强消费者食品质量安全宣传并重视检测与认证机构在食品质量安全方面的作用。 相似文献