针对中波广播在世界数字无线电广播(Digital Radio Mondiale,DRM)标准下的应用需求,研究中波调谐技术,阐述其基本原理和关键技术,重点分析数字频率合成、信号同步、滤波器设计及干扰处理等技术的实现方法,同时提出多通道抗干扰调谐结构...针对中波广播在世界数字无线电广播(Digital Radio Mondiale,DRM)标准下的应用需求,研究中波调谐技术,阐述其基本原理和关键技术,重点分析数字频率合成、信号同步、滤波器设计及干扰处理等技术的实现方法,同时提出多通道抗干扰调谐结构和软定义调谐自调机制等优化策略,旨在提高调谐精度和中波广播系统在复杂电磁环境中应用的稳定性。展开更多
文中对世界数字广播(Digital Radio Mondiale,DRM)系统进行了基础性的阐述,深入探讨了其关键技术的核心实现途径,关注了音频编码技术,提出了详尽的设计理念与方法,展示了两款DRM接收机的设计方案。上述方案保障了从模拟到数字广播的平...文中对世界数字广播(Digital Radio Mondiale,DRM)系统进行了基础性的阐述,深入探讨了其关键技术的核心实现途径,关注了音频编码技术,提出了详尽的设计理念与方法,展示了两款DRM接收机的设计方案。上述方案保障了从模拟到数字广播的平滑过渡。展开更多
The dry reforming of methane(DRM)reaction enables the resourceful utilization of two greenhouse gases,holding significant implications for mitigating the climate crisis and preserving ecological balance.Based on our p...The dry reforming of methane(DRM)reaction enables the resourceful utilization of two greenhouse gases,holding significant implications for mitigating the climate crisis and preserving ecological balance.Based on our previous systematic research on the optical and electronic properties of Ce_(1-x)Zr_(x)O_(2)catalysts,this study constructs a model of Ni13 clusters supported on the(111)surface of Ce_(1-x)Zr_(x)O_(2)(x=0,1/4,1)catalysts using density functional theory(DFT).Simulate the activation of CH_(4)molecules and the formation of product CO and H_(2)during the thermocatalytic DRM reaction.The results indicate that Ce–Zr doping optimizes the charge distribution on the catalyst surface,thereby accelerating the reaction process.The CH species react through an oxygen-assisted dehydrogenation pathway,effectively suppressing carbon deposition.By introducing an additional electric field to simulate the photogenerated carrier effect induced by light excitation,the electron transfer from the support to the active metal is enhanced.The separation and migration of photogenerated electron-hole pairs alter the adsorption configurations and transition state energies of reaction intermediates,reducing the reaction potential energy curve.This study provides a solid theoretical foundation for the development of highly efficient photothermal-coupled DRM catalysts.展开更多
2009年8月ETSI颁布的DRM(Digital Radio Mondiale)标准将调频段DRM数字广播囊括其中,介绍该标准中调频段DRM数字广播的优势与信道部分的技术特性。调频段DRM数字广播通过信道编码技术、信道复用、OFDM调制等技术,实现调频段广播信号的传...2009年8月ETSI颁布的DRM(Digital Radio Mondiale)标准将调频段DRM数字广播囊括其中,介绍该标准中调频段DRM数字广播的优势与信道部分的技术特性。调频段DRM数字广播通过信道编码技术、信道复用、OFDM调制等技术,实现调频段广播信号的传输,与DAB相比可快速而平滑地实现FM波段广播由模拟向数字的过渡。展开更多
作者阐述了数字版权管理DRM(Digital Rights Management)的基本概念,功能架构,以及涉及的技术.对DRM系统中的密钥管理、数字权利的转移、数字版权描述做了扩展,研究了数字内容发行中的必要组成部分,并结合实际商业营运模式提出了可携式...作者阐述了数字版权管理DRM(Digital Rights Management)的基本概念,功能架构,以及涉及的技术.对DRM系统中的密钥管理、数字权利的转移、数字版权描述做了扩展,研究了数字内容发行中的必要组成部分,并结合实际商业营运模式提出了可携式电子出版品和可携式电子书载具的概念以及可携式电子书版权控制的基本思想.依据电子书交换系统EBX(Electronic Book Exchange)的DRM技术构建了一个电子书发行平台,实现了电子书出版、销售以及用户购买、阅读过程中的版权保护.展开更多
文摘针对中波广播在世界数字无线电广播(Digital Radio Mondiale,DRM)标准下的应用需求,研究中波调谐技术,阐述其基本原理和关键技术,重点分析数字频率合成、信号同步、滤波器设计及干扰处理等技术的实现方法,同时提出多通道抗干扰调谐结构和软定义调谐自调机制等优化策略,旨在提高调谐精度和中波广播系统在复杂电磁环境中应用的稳定性。
基金projects supported by National Natural Science Foundation of China(No.52106179)Fundamental Research Program of Shanxi Province(No.202403021221066)+2 种基金Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(No.20230012)Shanxi Scholarship Council of China(No.2023-065)Graduate Education Practical Innovation of Shanxi Province,China(No.2024SJ093).
文摘The dry reforming of methane(DRM)reaction enables the resourceful utilization of two greenhouse gases,holding significant implications for mitigating the climate crisis and preserving ecological balance.Based on our previous systematic research on the optical and electronic properties of Ce_(1-x)Zr_(x)O_(2)catalysts,this study constructs a model of Ni13 clusters supported on the(111)surface of Ce_(1-x)Zr_(x)O_(2)(x=0,1/4,1)catalysts using density functional theory(DFT).Simulate the activation of CH_(4)molecules and the formation of product CO and H_(2)during the thermocatalytic DRM reaction.The results indicate that Ce–Zr doping optimizes the charge distribution on the catalyst surface,thereby accelerating the reaction process.The CH species react through an oxygen-assisted dehydrogenation pathway,effectively suppressing carbon deposition.By introducing an additional electric field to simulate the photogenerated carrier effect induced by light excitation,the electron transfer from the support to the active metal is enhanced.The separation and migration of photogenerated electron-hole pairs alter the adsorption configurations and transition state energies of reaction intermediates,reducing the reaction potential energy curve.This study provides a solid theoretical foundation for the development of highly efficient photothermal-coupled DRM catalysts.
文摘2009年8月ETSI颁布的DRM(Digital Radio Mondiale)标准将调频段DRM数字广播囊括其中,介绍该标准中调频段DRM数字广播的优势与信道部分的技术特性。调频段DRM数字广播通过信道编码技术、信道复用、OFDM调制等技术,实现调频段广播信号的传输,与DAB相比可快速而平滑地实现FM波段广播由模拟向数字的过渡。
文摘作者阐述了数字版权管理DRM(Digital Rights Management)的基本概念,功能架构,以及涉及的技术.对DRM系统中的密钥管理、数字权利的转移、数字版权描述做了扩展,研究了数字内容发行中的必要组成部分,并结合实际商业营运模式提出了可携式电子出版品和可携式电子书载具的概念以及可携式电子书版权控制的基本思想.依据电子书交换系统EBX(Electronic Book Exchange)的DRM技术构建了一个电子书发行平台,实现了电子书出版、销售以及用户购买、阅读过程中的版权保护.
