CHƯƠNG 5 PHÂN TÍCH VÀ HIỂN THỊ DỮ LIỆU pdf

CHƯƠNG 5
PHÂN TÍCH VÀ HIỂN THỊ
DỮ LIỆU
GIS for Everyone
ĐẠI HỌC QUỐC GIA TP. HỒ CHÍ MINH
TRƯỜNG ĐẠI HỌC BÁCH KHOA
Trình bày: LƯU ĐÌNH HIỆP
Tel: (84-8)864 72 56 ext 5383
Email:
Truy vấn
• Selective search without modifying the original data (for
output)

Phân nhóm
Raw data Classified data

• Professional experiences
• Expert votes
• Empirical or analytical models
Chồng lớp
• adding layers, subtracting, multiplication, division, etc.
• Raster
Input data layer A
Input data layer B
Output data layer
Chồng lớp
• Arithmetic operation on two data layers using the vector
data model
Input
data layer A
Input

data layer B
Output
data layer
Spatial data
Attribute data
Chồng lớp
Phân tích địa hình (bề mặt)
• Elevation

• Slope angle
- rate of change in elevation, by degree of arc or by %
slope

• Slope aspect
- the direction that a surface faces



Nội suy không gian
• Linear interpolation
Known values
Known and predicted
values after interpolation
Nội suy không gian
• Thiessen polygon
- Defines area of influence around a point in a way
that polygon boundaries are equidistant to
neighboring points

Nội suy không gian
Nội suy không gian
• Inverse Distance weighted
- IDW works by using a weight based on the distances
from an unknown value to known values

Arthur Lambor, Cornel University
© Paul Bolstad, GIS Fundamentals
Nội suy không gian
• Trend surface
- Polynomial regression to fit a least-square surface to the
input points

First-order (linear) trend surface Second-order (quadratic) trend surface
is Spatial Interpolation?
Nội suy không gian
• Fourier series
Single harmonic in
X
1
direction
Two harmonics in X
1

direction
Single harmonic in
both X
1
and X

2

directions
Two harmonics in
both directions
Theissen
Arthur Lambor, Cornel University
Inverse Distance Weighting
Arthur Lambor, Cornel University
Kriging
Arthur Lambor, Cornel University
Phân tích mạng
• Shortest and fastest routes

Phân tích mạng
• Traffic assignment

Phân tích mạng
• An evaluation of best sequence to visit each of a set of
stops and the best route between the stops


Phân tích mạng
• Delineate service areas

Phân tích mạng
• Evaluate possible facility locations


Phân tích mạng (dòng chảy)

• Applications – use of a seek function to model flow path
Phân tích mạng (dòng chảy)
• Application – find path through a sewer system from point
A to point B