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Spatio-Temporal Design for Urban Planning Supervisor: Mr. Ather Ashraf Assistant Professor, GIS Center, PUCIT, University of the Punjab, Lahore, Pakistan.    Researcher: Asif Ali, Salman Haider, Jahanzaib Sohail Rana, Muhammad Idrees MSc IN GIS Email: asifokaravi@gmail.com, salmankazmi2@gmail.com, sohailjahanzaib@gmail.com, idreesgis@gmail.com Abstract The land use change is an essential process which is happing day by day on our earth. There has been an attempt to model the phenomena of real world. The spatial data changes with respect to time. So it is very essential to keep the record of spatial changes that happens on our land which helps us in future decision making. GIS has the ability to handle spatial change and temporal changes.The goal of this research is to develop an application, which helps to keep all the temporal changes that occur in the spatial data and help us to investigate/examine the spatial changes which take place on land with respect to time span by retrieving spatio-temporal data according to user requirements. This will help planners in decision making and future predications. Introduction Urban data changes day by day with respect to time. This rapid urbanization has created tremendous pressure on urban service and created major socio-economic and physical problems. If the land is to be managed efficiently in urban areas, then accurate information on current land use needs to be collected on regulation to forecast the impact of land use change. Where to get data for urban planning and management is one issue but how to manage this data is still a challenging task. This research focuses on the management of theses data with respect to time. Problem arising from conventional GIS from the data management and query processing perspective can be classified as follow:
Here we shall discuss two types of spatio-temporal models
One of the simplest spatio-temporal data models is the snapshot model [2]. Temporal information has been incorporated into this spatial data model by time-stamping layers. In this model, every layer is a collection of temporally homogeneous units of one theme. It shows the states of a geographic distribution at different times without explicit temporal relations among layers. ? The aim of this investigation is to see if these methods have the ability to store/reconstruct complete geographical states, offer functionality for comparisons between states, and describe the events that lead to changes between states. STER Model In STER model, three types of time aspects can be defined: (i) valid time, (ii) transaction time, and (iii) existence time. The valid time of a fact is the time when the fact is true in the modeled reality. In other words, the time interval that a value is valid for a land parcel represents the valid time for the value attribute of the land parcel. The transaction time of a geo database is the time when the element is the part of the current state of the geo database. For example, a land parcel may exist between 1951 and 1999 years. However, it may be recorded in a database by 1995. The transaction time of this land parcel is then defined between 1995 and 1999. The transaction time is applied not only to facts but to any element that may be stored in a database. The existence time refers to the time when the object exists. For example, the existence time of above mentioned land parcel is between 1983 and 2006. [3] Research Methodology. The Conceptual Schema. As we are going to show the spatio-temporal changes in urban areas, so on the top level we have a town or area of study, which is divided into two parts i.e. into roads and parcels, and parcels are further sub-categorizes into residential, commercial, industrial, health, educational, recreational, open spaces and graveyards. Similarly each, road has a “right of way”. All these are the entities, and each of these entities has attributes which shown in the following figure.  Figure. STER for Urban Planning. Logical Schema. Logical schema involves the normalization of ERD. The normalized form of our ERD is shown in the figure.  Figure. Normalized ERD. Physical Schema. Our main concern in this work is on the following terms that we use in our attributes of the parcels, which are
After finishing this task we develop an interface using technologies which are mentioned above i.e. ArcGIS SDK and Runtime embedded in Visual studio 2005. The land use is Symbolized according to the Color scheme as show in the right side of the Interface and you can check in or check out any Land use Type according to your requirements. We have created two tools in this Interface. One is for Adding new Parcel and the other is for deleting the Parcel and some other functionality which is described below.  Figure. Spatio-Temporal Interface for Urban Planning. Then we added the following functionalities to the interface programmatically.
One of the simplest spatio-temporal data models is the snapshot model [Lan88]. Temporal information has been incorporated into this spatial data model by time-stamping layers. In this model, every layer is a collection of temporally homogeneous units of one theme. It shows the states of a geographic distribution at different times without explicit temporal relations among layers. Time is considered as an attribute of the location. The model is the simplest way to represent spatio-temporal information, but its capability to support complex queries is the most limited. It is therefore capable to answer simple spatial, temporal and spatio-temporal queries but it is difficult for the model to resolve all the other types of queries. Adding New Parcel We can add new parcel with the help of “Add polygon” tool in that area where new building were build e.g.  Figure. Creating new parcel When we are adding a new parcel to the map in any type of parcel i.e. whether it is a residential, commercial, recreational, open space, educational, health, industry or religious, the parcel adding time will be its “start existing time” “SET” let suppose it is “20010723” i.e. its existence in reality starts on 23rd of July 2001 in any type of parcel. When we are adding a new parcel whenever any change occurs, then we have to add some information to that parcel. For this purpose we have constructed a form, which will ask for the necessary information to be provided when we shall add any new parcel. First of all we have to give its “TYPE” i.e. whether it belongs to a residential area or commercial or any other, then we have to give its “NAME”, then we have to give its “SET” i.e. Start Existing Time and the given time will be its beginning time. Deleting Parcel We can delete any parcel with the help of “Delete Tool”. For this first of all select the Parcel which you want to delete then Click the delete button. The selected Parcel will be deleted permanently. The below figure show the Parcel which has Commercial Type is being Deleted.  Figure. Deleting parcel We have added some functionality to our interface e.g. we can see temporal data of different themes. For temporal data we have divided our data into time spans i.e. 1985, 1995, 2005 and current data when we click on the 1980 time span radio button then it will show all parcels which were built till 1980. When we click on the 1985 time span radio button, then it will show all new parcels which were built till 1985 and so on. The below figure show the data which were till 1980.  Figure. Land Use Spatial Data in 1980. The below figure show the data which were till 1985.  Figure. Land Use Spatial Data in 1985. The below figure show the data which were till 1990.  Figure. Land Use Spatial Data in 1990. The below figure show the data which were till 1995.  Figure. Land Use Spatial Data in 1995. The below figure show the data which were till 2000.  Figure. Land Use Spatial Data in 2000. The below figure show the data which were till 2005.  Figure. Land Use Spatial Data in 2005. 3D View The below figure show the land use in a 3D View. In this we create a Time Track by clicking the create button. This will ask the Start Time and the End Time and Time Interval and then it will create snaps according to our inputs and Store it. Now this is ready for play. This will show the land use as it is built according to the Time and will show the Parcel till our End Time.  Figure. Final View Spatio-Temporal Interface for Urban Planning in a 3D View. Conclusion. In this application, the design and implementation of urban change with a Spatio-temporal modeling approach was described. The system requirement analysis for the urban planning geo database was carried out in the DHA Phase-II Lahore Pakistan. The system requirements were analyzed according to data types collected in the existing urban planning. The basic urban planning queries showed that an urban planning geo database should store historical information on land parcels and related objects. A spatial and temporal geo database modeling approach is inevitable to design and implement an urban database. This application can help Urban Planners in Spatial Decision Support system for future urban growth. The STER model has met the requirements for a spatiotemporal conceptual model. It does not require an intensive effort for learning and using. It is orthogonal to Entity-Relationship (ER) model and can be added to or removed from traditional ER model constructs when needed. Adding EER model constructs to STER model has improved the expression power of the STER model. There is a lot of work for future in the spatio-temporal context of urban planning. Due to the emerging and new technologies we have a lot of opportunities for the enhancement of our project We have to build software which would have editing tools for the advanced editing and would have analysis tools for the analysis and planning of future regarding urban planning. Through which we can make future plans for our urban areas. References.
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