ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensionai GIS", Bangkok, May 23-25, 2001
AN COMPOSITE TEMPORAL DATA MODEL IN CADASTRAL INFORMATION SYSTEM
Changsheng XUB 1 i Qingquan Lira,and Bisheng YANGra, Yuanchun HUAra, Shiwu XUra
l1l E_mail:xuechangsheng@telekbird.com.cn, tel:0571 -7223105(o);fax:0571 -7223095
|2| E_mail:lqq@wtusm. edu.cn
131 E_mail:BSYang@263.net
141 E_mail:Y.C. Hua@163.net
• 5) E_mail:Xushiwu@cug.edu.cn
i 1 ! w Institute of Land Surveying & Planning of Zhejiang Province ,40 Qingyue Street,Hangzhou 310003, P.R.China
mpjpjwuhan University, 139 Luoyu Road, Wuhan 430079, P.R.China
151 Chinese Geology university, 31 Lumo Road, Wuhan 430074, P.R.China
KEYWORDS: temporal data model, CIS.
ABSTRACT
With the rapid development of land transactions, land disputes become more and more frequent. Not only the current information of land
is cared about, but also its historical records become more and more important in cadastral management. A composite temporal data
model is proposed. The authors describe its data structure and the course of the implementation in detail.The composite temporal data
model, which has little redundant storage, quick historical retrieval and security of storing data, can meet the basic need of temporal
GIS.
1. INTRODUCTION
Cadastral Information System (CIS) is a branch of Land
Information System (LIS), which is one of GIS applications in
land management. CIS is Office Automation of cadastral
management. In general, cadastral management includes land
registration, land investigation, land classification and valuation,
land statistics and cadastral archive management. Aparcel is the
smallest spatial unit of cadastral management, which is a
contiguous area, of land within unique, homogeneous property
interests. It seemed that people’s interest and attention to the
parcel mainly focused on the aspect of spatial information (for
example the boundary of a parcel) and attribute information (for
instance, ownership or usership) , not sufficiently on time factor
(such as, the beginning and ceasing time of a parcel). With the
rapid development of land transactions, land disputes become
more and more frequent. People need more detailed historical
records of parcel changes (such as, many times it has
changed and why it was sold or changed) and regard them as
legal basis in many land disputes. In other words, not only the
current information of land is cared about, but also its historical
records become more and more important in cadastral
management. At present, how to efficiently store and manage
historical data has become a factual criterion of evaluating a
CIS.
2. REVIEW OF TEMPORAL DATA MODEL
Many scholars have advanced a lot of temporal data models.
Techniques used in current temporal GIS data models include
the snapshot model (Armstrong, 1988), the differential object
model (langran and Chriman, 1988), time-based data model
(worboys, 1992; Shi and Zhang, 1995). The snapshot approach
has disadvantages of redundant storage of unchanged data,
difficult extraction of local detailed changes, inexplicit temporal
information and operation inefficiency (Peuquet and Duan, 1995).
The differential object model has difficulty in preserving object
persistency because this model requires constant updating
object identities upon continual changes in spatial units and
configurations (May Lun, 1997). Time-based data model, which
uses time indexes and event indexes to access previous
information, is complex in data structure. Existing temporal GIS
models are incapable of describing all kinds of spatial changes.
3. THE COMPOSITE TEMPORAL DATA MODEL
3.1 THE DATA STRUCTURE
To overcome the shortages of the above models, a composite
temporal data model is proposed. Theoretically, time axis
extends from the past to the future infinitely, correspondingly