稳定的有线/无线通信链路是北斗/GNSS-RTK技术应用于滑坡灾害监测的必要条件,当监测区域地面通信基础设施缺失或突发险情引起通信链路中断时,滑坡监测工作难以开展。针对于此,研究并分析了北斗三号区域短报文通信(regional short messag...稳定的有线/无线通信链路是北斗/GNSS-RTK技术应用于滑坡灾害监测的必要条件,当监测区域地面通信基础设施缺失或突发险情引起通信链路中断时,滑坡监测工作难以开展。针对于此,研究并分析了北斗三号区域短报文通信(regional short message communication,RSMC)技术应用于滑坡灾害监测的可行性。首先设计了一种基于北斗三号RSMC的GNSS观测数据编码方法,在此基础上分析了基准站与流动站观测数据的不同传输方案对滑坡灾害监测的影响。最后对其中两种可行性较高方案的通信指标与定位效果进行了评估,结果表明,基准站采用4G、监测站采用北斗三号RSMC的第一种传输方案,平均解算时延优于1.1 s,传输成功率可达98.46%,实时监测序列精度在水平方向优于1cm,高程方向可达厘米级水平。该方案保持了监测序列的高频率高精度实时获取,同时提升了地面通信受限时监测信息的可用性。展开更多
The study on design and implementation of end to end encrypted Short Message Service (SMS) using hybrid cipher algorithm is motivated by high rate of insecurity of data observed during Short Message Service (SMS) on M...The study on design and implementation of end to end encrypted Short Message Service (SMS) using hybrid cipher algorithm is motivated by high rate of insecurity of data observed during Short Message Service (SMS) on Mobile devices. SMS messages are one of the popular ways of communication. The aim therefore is to design a software for end to end encryption short message service (SMS) that can conceal message while on transit to another mobile device using Hybrid Cipher Algorithm on Android Operating System and implement it for security of mobile SMS. Hybrid encryption incorporates a combination of asymmetric and symmetric encryption to benefit from the strengths of each form of encryption. Various encryption algorithms have been discussed. Secondary sources were employed in gathering useful data. In this research work three methodologies are employed—Structured System Analysis Design Methodology (SSADM), Object Oriented Analysis Design Methodology (OOADM) and prototyping. With the help of the three cryptographic algorithms employed—Message digest 5 (MD5), Blowfish and Rivest-Shamir Adleman (RSA);integrity, confidentiality, authentication and security of messages were achieved. The messages encrypted by developed application are also resistant to brute force attack. The implementing programs were coded in Java.展开更多
文摘稳定的有线/无线通信链路是北斗/GNSS-RTK技术应用于滑坡灾害监测的必要条件,当监测区域地面通信基础设施缺失或突发险情引起通信链路中断时,滑坡监测工作难以开展。针对于此,研究并分析了北斗三号区域短报文通信(regional short message communication,RSMC)技术应用于滑坡灾害监测的可行性。首先设计了一种基于北斗三号RSMC的GNSS观测数据编码方法,在此基础上分析了基准站与流动站观测数据的不同传输方案对滑坡灾害监测的影响。最后对其中两种可行性较高方案的通信指标与定位效果进行了评估,结果表明,基准站采用4G、监测站采用北斗三号RSMC的第一种传输方案,平均解算时延优于1.1 s,传输成功率可达98.46%,实时监测序列精度在水平方向优于1cm,高程方向可达厘米级水平。该方案保持了监测序列的高频率高精度实时获取,同时提升了地面通信受限时监测信息的可用性。
文摘The study on design and implementation of end to end encrypted Short Message Service (SMS) using hybrid cipher algorithm is motivated by high rate of insecurity of data observed during Short Message Service (SMS) on Mobile devices. SMS messages are one of the popular ways of communication. The aim therefore is to design a software for end to end encryption short message service (SMS) that can conceal message while on transit to another mobile device using Hybrid Cipher Algorithm on Android Operating System and implement it for security of mobile SMS. Hybrid encryption incorporates a combination of asymmetric and symmetric encryption to benefit from the strengths of each form of encryption. Various encryption algorithms have been discussed. Secondary sources were employed in gathering useful data. In this research work three methodologies are employed—Structured System Analysis Design Methodology (SSADM), Object Oriented Analysis Design Methodology (OOADM) and prototyping. With the help of the three cryptographic algorithms employed—Message digest 5 (MD5), Blowfish and Rivest-Shamir Adleman (RSA);integrity, confidentiality, authentication and security of messages were achieved. The messages encrypted by developed application are also resistant to brute force attack. The implementing programs were coded in Java.
