Applied Research Of Hydrographic Data Management Based On Electronic Chart

Waterway survey is a critical part of waterway construction,for the rational organization of channel excavation,construction quality control,engineering process control,channel deposition analysis and other aspects it plays an important role in guiding decision-making,simultaneous measurement of work provides a reliable technical guarantee for safe navigation of channels,also provides valuable material for the quantities of the works.The traditional method of sea survey is the use of conventional instruments measured with resection,the principle of this method is to use the two control points on shore by two theodolite intersection point to reach a sea plane location,and through the tracking ship measure the sea depth of the moment by the water hammer,this method is not only a waste of manpower and time,but also very poor accuracy,the measurement results is difficult to achieve construction requirement.Now,with need of construction and increase of the technical level,the global satellite positioning system(GPS) and echo sounders have been deep into all areas of construction,making it easier and more flexible to measure at sea,and measurement accuracy high. The data collected are sent to shore-based Measurement Center in real-time via GPRS wireless network to update the central database. And the measurement data are an important material of channel management,and the basis of scientific research, construction of channel,also are the important results of all measurement of channel.So as the measuring units of channel and management unit of mapping data,channel survey centre how to efficiently manage measurement data and the measured data play the effective value,every coherent units can quickly use measuring material,thus further promote waterway construction and service level,become the focus of this topic research,in addition to this topic realizes combination of electronic chart and channel survey,real-time display of the survey vessel is good for survey centre to know that real-time trends of the survey vessel,this is also able to offer service for the channel business.The main tasks of this Topic are a series of analysis to do for hydrographic data acquisition,measurement data transmission and the effective management of measurement data.(1)Use echo sounders to collect water depth data,and use GPS location to collect data information of vessel's position,analysis interference of possible existence of measuring data,and analysis the collected original data and processing anti-jamming.(2)Use GPRS wireless data transmission network to complete the transmission of measurement data,and design and implementation of communication between user terminal and data center.(3)How to effectively manage measured data,how to design the data structure of measurement data,how to design database for measurement data security store, security query,security management and a series of safety operation.Also analyzes the management system structure and overall dynamic process measured data.(4)Introduces the origin of electronic chart and several stages of electronic chart experienced,such as from an initial paper chart to now electronic chart that it can be edited, modified, inquiried,current electronic chart has broad prospect, has been used to maritime career.Meanwhile introduces S-57 data transmission standards of electronic chart, data structure and data encapsulation standards and chart shows, it also gives parts of implementation code of the electronic chart based on real-time display.