Code : 2020041
Event Name : A Record Survey for Lion Rock Tunnel using Mobile Laser Scanning and Imagery System (MLSI) in Highways Department
CPD Code : Formal Events
Speaker : Sr TSANG Yiu Cheung, Alvin

Alvin is currently an assistant land surveyor in Housing Department. He is a council member of Land Surveying Division, HKIS since 2019. This talk was recommended by LSEDC. The APC Practical Task prepared by the speaker was awarded with the Best LSD APC Award 2019.
Event Date : 2020-06-04
Event Time : 7:00 pm - 8:30 pm
CPD Hour(s) : 1.5
Divisional PQSL Hour(s) : 1.5
Venue : By online media – Zoom
Division : LSD
Organizer : Land Surveying Division
Fee : HK$150 for members; HK$180 for non-members (HK$30 walk-in surcharge on all prices listed)
Priority : First-come-first-served
Language : Cantonese supplemented by English
Details :

Mobile Laser Scanning and Imagery System (MLSI) is a mobile mapping solution procured by Survey Division of Highways Department (HyD) to support different kinds of road related and asset management works in HyD.


In this talk, Alvin will introduce how a record survey for Lion Rock Tunnel was performed using MLSI. The design of survey scheme as well as the analysis of absolute and relative position accuracy of data collected under different durations of Global Navigation Satellite System (GNSS) outages will be discussed. In addition, various adjustment methods and combinations that applied in correcting the datasets will be compared and evaluated. Alvin will also shall his view on a suggested survey workflow for conducting tunnel record surveys using MLSI during the end of the talk.

Remarks :

Rescheduled from 23 March 2020

The event will be conducted online via ZOOM. Successful registrants will be notified separately via email with the web link and password in due course to the online event .

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Payment : HKD 150