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Certificate of the

LSGI Departmental

“Best Researcher of

the Year 2013”


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2013 CSCN Conference Best Paper Award

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2013 CSCN Conference Best Paper Award

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Dr. Liu received an honor of Individual Award of Shenzhen Virtual University Park for National Research Project, by the Shenzhen Municipal Science and Technology Innovation Council December 2012.

The Inaugural Early Career Award Recipient (首届杰出青年学者奖”), Hong Kong Research Grants Council (RGC), Hong Kong Special Administrative Region (HKSAR). Dr. Liu was one of the 19 recipients out of 334 applicants across all the universities in Hong Kong in 2012 (success rate: 5.69%). He is also one of only 3 recipients in PolyU and one of 6 recipients in the Engineering Panel under Hong Kong RGC.



































The six recipients of Early Career Award of the Engineering Panel and the Engineering Panel Chairman of Hong Kong Research Grants Council (Dec. 12, 2012)



































[May 26, 2013] Recently, This paper was coauthored by Zhizhao Liu, Rui Xu, Yu Morton, Jisheng Xu, Wouter Pelgrum, Steve Taylor, Wu Chen and Xiaoli Ding.



[May. 22, 2013] We are very pleased to announce that Dr. Liu is to receive the Excellent Paper Award from the 2013 4th Chinese Satellite Navigation Conference (CSNC 2013) in Wuhan, China.


In the recent 2013 China Satellite Navigation Conference (CSNC) held May 15-17 in Wuhan, Dr. George Zhizhao Liu from the Department of Land Surveying & Geo-Informatics (LSGI) received the Excellent Paper Award for his paper “The First PPP-based GPS Water Vapor Real-Time Monitoring System in Pearl-River-Delta Region, China” co-authored with Research Associate Dr. Min Li. This paper presents their research findings of developing the first atmospheric water vapor real-time monitoring system for the Pearl-River-Delta (PRD) region using the latest Global Positioning System (GPS) Precise Point Positioning (PPP) technique. Based on their technique, now the amount of water vapor in the atmosphere over the PRD region can be quickly and accurately computed from GPS satellite signals. Since April 2012, the PolyU researchers have been supplying their atmospheric water vapor data to the meteorological agencies around the PRD region to support their daily services and research, including Hong Kong Observatory, Macao Meteorological and Geophysical Bureau, Guangdong Meteorological Bureau and Shenzhen Meteorological Bureau.


This year is the first time for CSNC to have the Excellent Paper Award. Dr. Liu was one of the nine award recipients out of 629 paper submissions (success rate: 1.43%). This research work was supported by the General Research Fund (GRF) of Hong Kong Research Grants Council (RGC).




[May. 11, 2013] We are very pleased to announce that Dr. George Zhizhao Liu was given an

honor of








[Dec. 12, 2012]







[July 23, 2012] We are pleased to share with you that our research project “Innovative Real-Time Cycle Slip Detection and Rectification for High Precision GPS Positioning” led by Dr. George Zhizhao Liu is funded by the Early Career Scheme (ECS), Hong Kong Research Grants Council (RGC), Hong Kong SAR Government. This project, together with 19 other projects across all the universities in Hong Kong, will be recognized with an “Early Career Award” (ECA), which is the first time to give ECA in the history of Hong Kong RGC.  For this project, one PhD student will be funded for three (3) years. Interested applications are welcome to contact Dr. Liu.


[July 23, 2012] We are pleased to share with you that our paper “Cycle slip detection and repair for undifferenced GPS observations under high ionospheric activity” co-authored by Changsheng Cai • Zhizhao Liu • Pengfei Xia • Wujiao Dai is published online @ GPS Solutions 4 July 2012. As of 23 July 2012 (20 days after the online publication), this paper has been downloaded 174 times, ranked 2nd in the list of most downloaded papers in the 30-days category. This paper can be downloaded @



 [14-15May 2012, Hong Kong]We are very pleased to announce theGNSSSchool(click for announcement) will be held attheDepartment ofLSGI,Hong Kong PolytechnicUniversity, 14-15 May 2012. Five distinguishedresearchers will give lectures for the GNSS School. The registration fee isonly HK$200 (approx. US$25).

Dr. Jade Morton: How GNSS Signal ProcessingAlters Signal Parameters: A Cautionary Tale in Using GNSS for Remote SensingApplications

Dr. PeterTeunissen: Carrier-Phase GNSS Attitude Determination

Dr. Maorong Ge: PPP Algorithms
Dr. Peng Fang:Global and Regional Reference Frame: Establishment, Maintenance, and Application
Dr. Danan Dong:Dig out signals from deep interior of the Earth using GPS measurements


[14 May 2012, HongKong]Dr. Jens Wickert, Acting headof section 1.1 “GPS/Galileo Earth Observation”

German Research Center for Geosciences GFZ, Potsdam,Germany is invited to give a talkonGPS/Galileo Earth Observation at GFZ: Recent activities and results” attheHong Kong PolytechnicUniversity.


[22 March 2012, Hong Kong] Dr.George Liu was invited to give a talk at theCivilEngineering and Development Department, Hong Kong Special Administrative Region(HK SAR) GovernmentonMonitoring Equatorial andLow-latitude Ionospheric Scintillation and Assessing Scintillation Impact onSatRef Network and GPS Applications in Hong Kong”.


[13 March 2012, Hong Kong] Weare very glad that our paper “A multi-sensor study of watervapour from radiosonde, MODIS and AERONET: a case study of Hong Kong” was published atINTERNATIONAL JOURNAL OF CLIMATOLOGY in December 2011. This paper wascoauthored by

Zhizhao Liu, Man Sing Wong,Janet Nichol and P. W. Chan. The citation is:Zhizhao Liu, Man Sing Wong,Janet Nichol and P. W. Chan (2011),Amulti-sensor study of water vapour from radiosonde, MODIS and AERONET: a case studyof Hong Kong,Int. J. Climatol.DOI: 10.1002/joc.3412.



[09 March 2012, Hong Kong] Dr.George Liu was invited to give a talk at theBeijingUniversity of Aeronautics and Astronautics (BUAA)onAn innovative approach for successful cycle slip detection and fixeven with arbitrarily large pseudorange errors”.


[08 March 2012, Hong Kong] Dr.George Liu was invited to present the Compass (Beidou) receiver evaluationresults at the Unicore Communications Inc. Beijing with a title “Preliminary Quality Analysis of the Pseudorange and Carrier PhaseData from Unicore Compass+GPS Receiver”.


[17 February 2012, Hong Kong]Dr. George Liu was invited to give a talk at the Chinese University of HongKong on “Water Vapor Observation in HongKong by Radiosonde, AERONET and MODIS”.


[17 January 2012, Hong Kong]Dr. George Liu is glad to receive fund support for the research “Improving the GPS SurveyingProductivity in Construction by Modeling the Localized Errors in the GPSNetwork—Case Study with Hong Kong’s SatRef Network” from Construction Industry Institute Hong Kong /PolyU Innovation Fund Governing Council. Thank youConstruction Industry InstituteHong Kong / PolyUInnovation Fund Governing Council!


[05 January 2012, Hong Kong]Dr. Jade Morton, Professor atthe Department of Electricaland Computer Engineering,Miami U, USA,was invited to give a talk atthe Department ofLSGI,Hong Kong PolytechnicUniversity on the topic “Ionosphere Effects and other GNSS and RF Navigation Research atMiami”.


[03 January 2012, Hong Kong]Dr. George Liu was invited to give a talk at the Hong Kong Observatory (HKO) on“Preliminary Investigation of Real Time PWV Monitoring in Hong Kong”.


[20 November 2011, Hong Kong]Dr. George Liu was invited to give a talk at the Wuhan University, China on “Evaluating Water Vapor Observed by Radiosonde, AERONET and MODIS inHong Kong”.


[11 October 2011, Hong Kong]Dr. Naser El-Sheimy, Professor at theDepartment of Geomatics Engineering, U of Calgary, Canada,was invited to give a talk atthe Department ofLSGI,Hong Kong PolytechnicUniversity on the topic “EmergingMEMS Sensors and Its Impact on Mapping and Navigation Applications”.



Last updated


[24September 2011, Hong Kong] We are very pleased to announce thatmultiple MSc level projects are available for thenew MSc students. The interested students are welcome tocontact Dr. George Liu by a visit HJ728 or an a call 27665961.


[24September 2011, Hong Kong] We are very pleased to announce thatone full-time PhD Scholarshipis available at the Micro-LARGE group.For printing, pleasedownload fromhere.

PhD Scholarship Available

Department of Land Surveying&Geo-Informatics

The HongKong Polytechnic University

Applications are called for one PhD scholarshipavailable at the Department of Land Surveying&Geo-Informatics (LSGI), TheHong Kong Polytechnic University (PolyU), Hong Kong, China. This position willbe open until the successful applicant is identified.


Thesuccessful applicant will be funded to study in a PhD program for three years(3 years) since early 2012 at PolyU and be working on the 3D tomographicmodeling of the water vapor in the greater China region. Specifically thecandidate will be responsible for the project “3D Water Vapor TomographicModeling by Assimilating Multiple Sensors to Support Extreme WeatherForecasting in Hong Kong and Mainland China” funded by the Hong Kong ResearchGrants Council (RGC).


Thisproject is technically supported by a team of international researchers. Thesuccessful applicant will work with scientists from Hong Kong Observatory,China Meteorological Administration (Beijing), The University of Calgary(Canada), and The RMIT University (Australia). The candidate will have theopportunity to physically visit and work with the international collaboratorswhen project progresses.


Required Qualifications:The successful applicant should hold at least thefollowing qualifications.

(a) a Master degree in Geomatics and/or other relateddisciplines (e.g. meteorology, mathematics, etc.);

(b) a good command of written and spoken Englishevidenced by TOEFL (Test of English as a Foreign Language), and/or IELTS(International English Language Testing System), and/or other test outcomes.

(c) experience in programming with computer languages(e.g. Visual C++, MATLAB®, etc);

(d) a good understanding of and experience in Kalmanfilter and Least-squares estimators;

(e) strong scientific data analysis and criticalthinking skills;

(f) strong communication skills to work within adynamic, internationally collaborative team;

(g) being able to conduct independent scientificresearch in a teamwork environment.


Applicants are invited to send the CV and publicationsamples to Dr. George Zhizhao Liu, who can be contacted no. (852)2766 5961, fax no. (852) 2330 2994 for further information. Onlyselected applicants will be contacted for interview. More information about theLSGI Department can be found at


Remuneration:Highlycompetitive salary will be offered to the successful applicant.

AdvertisementDate:11 September 2011


[24September 2011, Hong Kong] We are very pleased to announce that ourGeneral Research Fund(GRF) application tothe Hong Kong ResearchGrants Council (RGC)was successfully fundedafter a fierce competition.Thetitle of this project is “3D Water Vapor TomographicModeling by Assimilating Multiple Sensors to Support Extreme WeatherForecasting in Hong Kong and Mainland China.


[24September 2011, Hong Kong] Our publication was reported in“Science Letter”on 7 June2011.



[24September 2011, Hong Kong]As of 23Feb. 2011our paper(link here)wasranked 3rdin the most downloaded papersin Journal of Geodesy based on the downloads in the past 90 days since itsfirst day of online publication, one of the internationally well recognizedjournals in Geomatics.

90days_download_Feb23_2011(after publish 90 days).png


As of 10 Feb. 2011ourpaper(linkhere)is ranked one of the 5 most downloaded papers in Journal of Geodesybased on the downloads in the past 77 days since its first day of onlinepublication, one of the internationally well recognized journals in Geomatics.

This paper developed afully automated cycle slip detection and repair algorithm for dual-frequencyGPS carrier phase measurements. It can be safely said that the cycle slipproblem that have been hanging over the GPS community as long as the GPShistory itself (~30 years) is well resolved.


This algorithm is extremelyeffective for high rate GPS data like 1Hz or higher. Virtually any size ofcycle slips can be detected and repaired.


For low rate GPS data (like30 sec data interval or larger) this algorithm can work for many cycle slipcases but it might be a little difficulty for small cycle slips.


This method has beenextensively tested and examined in many scenarios such as:

o  High dynamics (space-borne GPS receiver payload on COSMICsatellite)

o  Highly disturbed ionosphere (daily Kp index =7.6 on 31 March2001, the 4thhighest daily Kp value in the past 30 years)


We look forward to hearingyour feedback and your comments/suggestions are always welcome.


Welcome to the homepage of Micro-Laboratory ofAtmospheric Research and Geomatics Engineering (Micro-LARGE)


Georgejoined the Department of Land Surveying&Geo-Informatics (LSGI), Facultyof Construction and Land Use (FCLU), The Hong Kong Polytechnic University(PolyU) on June 24, 2009. He and his family arrived at Hong Kong on June 23,2009 from Calgary, Canada after George had lived, worked, and studied inCalgary for nearly 10 years.


Hong Kong isa quite dynamic city and is quite different from Calgary. One most distinctdifference is the weather.


We, theMicro-LARGE, are striving to the highest level of excellence in teaching,research, and community service.

It is ourdestination goal to research and use the modern Geomatics technologies toimprove the living experience of the world’s people.


We arewelcome all kinds of collaborations to achieve our destinations. If you have any interests, please don’thesitate to

contact Dr.George Liu.


Geomatics, an incredibly critical technology inthis information era!


In thisworld, scientists, engineers, researchers, and actually many people are workinghard every day to try to answer the following 6 most fundamental questions morecorrectly and more precisely:

1) When 2)Where 3) Who 4)What 5)Why 6)How

At present,we can easily answer “When” in a completely numerical way because our time hasbeen digitalized, for instance: the UTC time at this point of writing is:2010-01-19 15:22:20. The numerical expression of time is an important progressin human being history and it is essential in this information era. So howabout the other 4W1H questions? Can you also use numbers to answer theremaining 4W1H questions? Answer is yes or no. If you use Geomatics technology,you can answer theWhere numerically too. Without geomatics,you can’t. Why? The answer is simple. For example, Hong Kong’s latitude andlongitude is: 22°20North,      114°11 East. Soyou can see the location of Hong Kong can be easily described in numericnumbers. How to get these numbers? It is a part of geomatics technology – usingGlobal Positioning System (GPS). With GPS, you may locate anywhere in the worldnumerically and display it on your computer screen. This is the power andbeauty of geomatics technology – answering one of the world’s most fundamentalquestions “WHERE” in a numerical way, a way people have never thought of and away that is so critical in today’s information era.


With GPStechnology, now any objects in our 4-dimensional space-time domain can becompletely digitalized and numerically stamped. This is the contribution ourgeomaticians are making to the society.


Note to Prospective Students:


Dr. GeorgeLiu is recruiting new students who are striving for pursuing a post-graduatedegree (MSc., MPhil, or PhD).

Theprospective students are encouraged to contact Dr. Liu for more information.The selected students will be provided

fullfinancial support during their study period at the PolyU.


Startingfrom 2009, a new program for PhD students “Hong Kong PhD Fellowship Scheme” isintroduced by the

Hong KongResearch Grants Council. The Fellowship Scheme aims to attract the outstandingstudents in the

world(including those from Hong Kong and Mainland China) to pursue their PhD degreeprograms in Hong Kong.


The Fellowshipwill provide an annual stipend of HK$240,000 (approximately US$30,000) and aconference

andresearch-related travel allowance of HK$10,000 (approximately US$1,300) peryear for a maximum

period ofthree years. 135 PhD Fellowships will be awarded for the 2010 / 2011 academicyear.


Moreinformation about this PhD Fellowship Scheme can be found @


Please note that,at all time, all kinds (MSc, MPhil or PhD) of applicants to PolyU are requiredto

submit theirapplication package through



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