Summary of technical doctoral thesis: Research on technical solutions to build mineral resource management database using WebGIS technology

The research objectives of the thesis: To establish the scientific basis and methodology to build WebGIS database in order to improve the efficiency of mineral exploitation management and activities.

MINISTRY OF EDUCATION AND TRAINING UNIVERSITY OF MINING AND GEOLOGY

DAU THANH BINH

RESEARCH ON TECHICAL SOLUTIONS TO BUILD MINERAL RESOURCE MANAGEMENT DATABASE USING WEBGIS TECHNOLOGY

Major : Surveying and Mapping engineering

Code : 9520503

SUMMARY OF TECHNICAL DOCTORAL THESIS

HANOI - 2021

The dissertation is completed at: Department of Imaging and Remote Sensing, Faculty of Geodesy - Map and Land Management, Hanoi University of Mining and Geology

Scientific Supervisors:

Assoc Prof., Dr Nguyen Truong Xuan

Reviewer 1: Prof Dr Vo Chi My

Vietnam Association of Georaphy, Cartography and Remotesencing

Reviewer 2: Dr Tran Trung Anh

Hanoi University of Mining and Gelogy

Reviewer 3: Dr Dao Ngoc Long

Vietnam Institute of Geodesy and Cartography

The dissertation will be defended before the Academic Review Board at the University level at Hanoi University of Mining and Geology at …:…… of date ……month ….year……

The thesis is available at the National Library of Vietnam or the Library of Hanoi University of Mining and Geology

INTRODUCTION

1 The urgency of the thesis

Vietnam has rich and diverse mineral resources However, the management of mineral resources still has many shortcomings and limitations; resulting in many illegal exploitation activities Therefore, the problem of rational management and use of mineral resources for re-investment, towards sustainable development is extremely important, urgent and a national strategy

Today, with the development of science and technology and the fourth industrial revolution taking place in all fields, including the fields of state management of mineral resources, the application of open source WebGIS platforms in building mineral resource management database is reasonable, suitable as well as to ensure topicality and reliability Although, there have been a number of studies on solutions based on open source WebGIS technology, but these studies still have some problems such as building solution, asynchronous techniques, and without integration of remote sensing image data processing technology

By such facts, the thesis "Research on technical solutions to build mineral resource management database using WebGIS technology"

is an urgent issue with practical scientific significance to solve the above situation

2 The research objectives of the thesis

To establish the scientific basis and methodology to build WebGIS database in order to improve the efficiency of mineral exploitation management and activities

3 Target and area of this study

- Target of this study: The direct scientific object is to study technical solutions to build WebGIS database for mineral resources classes, suitable for the efficient management of mineral resources in the practical conditions of Vietnam

- Area of this study: Research scope of content is open source WebGIS technology and some techniques for extracting mineral information on remote sensing image implemented in Quy Hop district - Nghe An province

4 Method of research

- Analysis and synthesis method: Collection of GPS measurement data, remote sensing image data, GIS vector data

- Remote sensing method: Processing of remote sensing image data is to build potential mineral data layer

- GIS method: processing, editing, spatial analysis of GIS data and remote sensing images

- Comparison method: comparing and evaluating the research results on the application of WebGIS technology in database building and mineral resource management; compare results of potential data layer on mineral resources based on information extraction technique based on remote sensing image with information related to mineral resource management, exploitation and use

- Modeling method: The research guide in the thesis is modeled to make it easy to understand and use in the data processing process

- Programming technique: selecting programming languages in combination with libraries to support data processing, designing and installing algorithms to build and test WebGIS systems to build databases and manage documents raw minerals

5 The scientific and pratical meaning of this thesis

- Scientific meaning: To establish a scientific basis and technical solutions to build WebGIS database for mineral resource management

- Practical meaning: The research results can be applied to build WebGIS database for mineral management in general and WebGIS database for Quy Hop district - Nghe An province in particular

6 Defense thesis and new points of the thesis

Defense thesis 1: The solution of extracting information from remote sensing images combined with GIS analysis based on an open foundation is meeting the topicality and reliability in building mineral resource database

Defense thesis 2: Open source WebGIS technology is a suitable technical solution satisfying to the management of large database of mineral resources

7 The new highlights of the thesis

- Propose technical solutions to build spatial database of mineral resources from the extraction technique of remote sensing image and GIS analysis based on open platform to serve the problem of monitoring and assessing the current situation

- Build mineral resource management system model based on open source WebGIS platform suitable for managing large database

of mineral resource

8 The layout of the thesis

The thesis is presented in 187 pages, including the preamble, thesis content, conclusions and proposals, author's work list, references, table of contents The content of the thesis includes 4 chapters with 106 figures and diagrams, and 24 tables/sheets

CHAPTER 1 OVERVIEW OF RESEARCH MATTERS ON BUILDING WEBGIS DATABASES FOR MANAGEMENT OF

MINERAL RESOURCES 1.1 Current situation of mineral resources in Vietnam and Nghe

An province

1.1.1 Current situation of mineral resources in Vietnam

Mineral resources have strategic significance and serve as a resource for the country's socio-economic development However, many illegal mineral exploration activities still take place One of the reasons leading to this situation is not good ability to monitor and manage mineral resources According to a study by the Institute of Natural Resources Management published in 2013, Vietnam ranked 43/58 in the capacity of mineral governance

1.1.2 Current situation of mineral resources in Nghe An province Nghe An is a province with abundant mineral resources compared

to many other provinces Nghe An province currently has 113 mineral mines with large reserves, 171 points of ore However, besides the positive development, the process of management and exploitation of mineral resources in Nghe An province has revealed many limitations such as:

- Some localities have lax in management of natural recources

- Nghe An mineral resource database includes many categories such as paper maps, documents, decisions, mineral exploration, investigation, mining and processing licenses as well as data on survey results, exploration but stored in many different agencies, not concentrated

Therefore, building a mineral resource database to integrate in a common management system is very necessary

1.2 Research situation in the world and in the country

1.2.1 Research situation in the world

Many scientific works have combined remote sensing and GIS to establish potential maps of mineral distribution or assess changes in

the current state on a large scale The techniques of extracting mineral information on remote sensing images, GIS analysis combined with scientific analysis in the fields of geology, geophysics, geochemistry have created sources of information about potential distribution mineral resources to assist in the process of surveying, exploring and evaluating the current state of mineral resources Many scientific studies have proven the usefulness and application of these technologies These include Kuosmanen - Finnish Geological Survey (1991), Sankaran Rajendran and Sobhi Nasir - Sultan Qaboos Oman University (2013), Seyed Mohammad Bolouki - Faculty of Mining and Metallurgical Engineering, University of Amirkabir technology, Iran (2019)

Today, the development of GIS and Web has strongly promoted the development of WebGIS, especially open platforms Open WebGIS platforms have been applied in the management, analysis, and evaluation of spatial data information based on distributed models (internet, corporate networks ) serving in many different social fields, including the management of mineral resources These include the researches of Sakhare - Motilal Nehru India National Institute of Technology (2010), Finnian OConnor - Technological University Dublin, Ireland (2011), Miao Liu - National Snow and Ice Data Center of America ( 2012), George Tudor - Romania Geological Institute (2012), Bo Jingfang and Yang Zongxi - China Beijing University of Geosciences (2012), Joel Bandibas - Japan Geological Survey Bureau under the Institute of Science and Japan National Advanced Industrial Technology (2013), Ranka Stankovic - Faculty of Mining and Geology of Belgrade University, Serbia (2016), Nan Li - Institute of Mineral Resources, Beijing Institute of Geosciences China (2018), Joel Bandibas and Shinji Takarada - Japan Geological Survey Department under the Institute of Science and Japan National Advanced Industrial Technology (2019) 1.2.2 Research situation in the country

With the strong development of geospatial technologies such as remote sensing, GIS, locating has effectively supported the collection, analysis, and processing of information of the mineral resources data; from there as a foundation to build a database of mineral resources Up to now, there have been a number of scientific works researching and applying remote sensing and GIS technologies to collect and process information and data that are

directly or indirectly related to information sources of environmental resources in general, as well as mineral resources in particular These include the studies of Truong Chi Quang - Can Tho University (2013), Le Van Thanh - Faculty of Environment and Natural Resources, Can Tho University (2014), Nguyen An Binh - Academy

of Science and Vietnam Technology (2015), Le Xuan Anh (2016), Nguyen Hoang Khanh Linh - Hue University of Agriculture and Forestry (2017), Nguyen Hai Hoa - Forestry University (2019) 1.3 Evaluation of research results

The results of the above studies have shown some remaining limitations as follows:

- The input data sources are only layers of mineral information, thematic maps, and mineral potential data layers based on remote sensing images have not been built

- These studies mainly use WMS standard to represent maps However, this is an old standard that cannot accommodate real-time mapping of map data

- These studies have not integrated supporting platforms for spatial data processing such as remote sensing image processing, GIS spatial analysis with WebGIS technology platforms

1.4 Issues being developed in the thesis

- Propose technical solutions to build spatial database of mineral resources from remote sensing image extraction technique and GIS analysis based on open foundation to serve the problem of monitoring and assessing the current situation

- Build a model of a large database management system of mineral resource based on an open WebGIS platform

CHAPTER 2 APPLIED SCIENCE BASIS OF OPEN SOURCE PLATFORM TO BUILD OF MINERAL RESOURCE

MANAGEMENT DATABASE 2.1 Open source WebGIS platform

2.1.1 WebGIS overview

WebGIS is a combination between Web and GIS This is a form

of distributed geographic information system, including geospatial database, Map Server (GIS server) and client computer In 1993, Xerox Corporation Research Center (PARC) has built the world's first mapping Website, marking the birth of WebGIS

2.1.2 Open source WebGIS development platform

GeoServer – Map server

Geoserver is an open source Web mapping server for the purpose

of connecting available geographic information to WebGIS websites using the OGC open standard In 2001, GeoServer was developed by the Open Planning Project Currently, in addition to the GeoServer, there are also a number of other map server software such as MapServer, Mapnik, MapGuide, QGIS Server, ArcGIS Server Among these map servers, the most famous are GeoServer, MapServer, ArcGIS Server softwares

PostgreSQL – database management system

PostgreSQL is an object relation database management system that has built from the POSTGRES project at the University of California Currently, PostgreSQL has become the most popular open source database management system PostgreSQL started to develop in 1986 The concepts, the data model, the system design, the rules, and the architecture of the storage manager are described in PostgreSQL PostgreSQL has been used to deploy many different applications in production and research such as: financial data analysis system, jet engine performance monitoring project, astronomical tracking database PostgreSQL is easy to set up and install It provides support for SQL and NoSQL PostgreSQL has been widely adopted by the industry in recent years Some leading companies in the world are using PostgreSQL such as Instagram, NextFLIX, Cybertec

PostGIS – Spatial database

PostGIS is a spatial database that has developed by Research Inc

in 2001 PostGIS supports geographic data types such as vector, raster; functions, operators, and spatial indices PostGIS provides features such as:

- Support processing spatial features of points, lines, polygons, polypoints, polylines, poly regions, geometrical assemblies

- Set up spatial projections and transform coordinate systems

- Handle spatial measurements such as area, distance

- Set up spatial indexes for high performance queries

- To handle calculations of geospatial set such as union, difference, symmetric difference and buffers

- Execute spatial queries based on structured query language (SQL)

QGIS/GRASS – Processing and editing of geospatial data

QGIS is an open source GIS software suite that runs on Linux, Unix, Mac OS and Windows operating systems QGIS is capable of building, editing and printing digital maps like ArcGIS commercial software QGIS supports the ability to process raster and vector files; connecting spatial databases such as PostGIS, SpatiaLite, Oracle, DB2 QGIS also supports data processing directly from GPS and supports field data processing Some main functions of QGIS:

- Display and stack vector and raster data in different formats (.tab, shp, gpx )

- Editing and printing of maps

- Access the database to build report forms/sheets

- GRASS satellite image digitization and interpretation tools

- Tools for processing data directly from GPS

2.2 Several data processing techniques based on the open WebGIS model

2.2.1 WMS

WMS is a standard that developed by OGC in 1999 to provide geographic reference map images on the internet WMS provides raster image data in many different resolutions and formats, used in many GIS applications WMS parameters allow the user to select maps of different sizes and resolutions and can be represented at any scale To determine the scale of the map in use, the server performs DPP calculation for the requested image and finds the nearest tile zoom level, according to the following formulas:

𝜆 : map viewport's maximum longitude

𝜆 : map viewport's minimum longitude

𝜃 : map viewport's maximum latitude

𝜃 : map viewport's minimum latitude

W: width of the map viewport in pixels

H: height of the map viewport in pixels

The calculation of the number of tiles needed for the map image

creation is based on the following formula:

- GetCapabilities: defines the supported FeatureTypes

- DescribeFeatureType: find the available properties for the FeatureTypes

- GetFeature: get the FeatureType's properties

2.2.3 TMS

TMS is a specification for tile Web maps that developed by OSGeo in 2006 The horizontal distance represented by each square tile is measured along the latitude at a certain latitude and calculated

cos(𝑙𝑎𝑡𝑖𝑡𝑢𝑑𝑒)

2( ) (2.6) The number of rows and columns is determined corresponding to each zoom level by the formula:

𝐶 = 2 (2.7)

𝑅 = 2 (2.8) The relationship between the tile address, geographic coordinates and zoom level is determined by the formulas:

2 − 180.0 (2.9)

2.2.5 GiST spatial indexing technique in PostGIS

The Generalized Search Tree (GiST) was originally described by Hellerstein It is a structure that provides a balanced and extensible tree access approach to indexed data types In addition to providing scalability for data types, GiST also consolidates different structures into the ones used for today's popular data types

Figure 2.15 The Generalized Search Tree (GiST)

2.3 Some algorithms extracting mineral information on remote sensing image

2.3.1 Mineral index

The band ratio between the two image bands K and L is defined

Clay Minerals Ratio (CMR)

Clay minerals characterize hydrothermal changes in rocks and they are strongly absorbed within a spectrum of about 2.2 μm, whereas strong reflections are in the 1.6 μm spectrum Thus the reflection spectrum of clay minerals can be enhanced by implementing the Shortwave Infrared (SWIR) ratio

𝐶𝑀𝑅 = 𝑆𝑊𝐼𝑅1 − min (𝑆𝑊𝐼𝑅1)

𝑆𝑊𝐼𝑅2 − min(𝑆𝑊𝐼𝑅2) + 1 (2.14)

In which, SWIR1: 1.55-1.75 µm; SWIR2: 2.08-2.35 µm

Iron oxide ratio index (IORI)

Iron oxide is one of the minerals commonly found in the natural environment Using the ratio between red and blue image brands will enhance the reflectivity of iron oxides:

𝐼𝑂𝑅𝐼 =𝑆𝑊𝐼𝑅

𝑁𝐼𝑅 (2.16)

In which, SWIR: 1.55-1.75 µm; NIR: 0.76-0.9 µm

2.3.2 The PCA Method

The PCA method is a multivariate statistical method that introduced by Pearson (1901) The PCA method has been widely used in remote sensing to create mineral geological maps During the implementation of the PCA, it is necessary to calculate a number of image statistics

Image average value

M is the vector representing the mean of the image X, with form:

n − 1 x (2.18)

In which, 𝜇 is the average value of the ith image band

Value of image variance

𝑉𝑎𝑟 is the vector representing the mean of the image X, with form:

𝑛 − 1 𝑥 − 𝜇 (2.19) Matrix of covariance images

Covariance between two image brands k and t, denoted by 𝑐 is calculated by the formula:

Through linear algebraic transformations, the covariance matrix 𝐶𝑜𝑣 c can be converted to a diagonal matrix with n non-negative values on the main diagonal

is determined as follows:

inf(𝑃𝐶 ) = 𝜆

∑ 𝜆 (2.21) 2.3.3 The DPCA method

In remote sensing image processing, the DPCA method was developed by Fraser and Green in 1987 when they studied the effects

of vegetation cover on hydroxyl-bearing minerals DPCA maps specific groups of information to a major component based on spectral reflectance characteristics The difference between DPCA and PCA is the pre-selective input to the DPCA method In the DPCA method, prior to proceed PCA, the baseline data is preliminarily extracted Preliminary extraction will be performed by channel ratio measurements Thus, DPCA is a combination of two