SMT201 AY2019-20G1 EX2 Moh Qing Loong Darren

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Part 1: Map Layout with four views

Gombak Road - showing the study area and the target roads

Gombak roads.jpeg


Description: The study area featured is Gombak, which is represented by brown. I use categorised symbols to show the different types of roads in the road network. There are cycling, footway, path paths, which are built for residents and public use. I labelled the paths with different colours instead of black to signify the distinction between different roads as it could be used for walking, transport. This is a general view, but further analysis on specific roads will be conducted to discuss in the later part.



Gombak Buildings - showing the study area and buildings

Gombak buildings.jpeg

Description: In Gombak, the distribution of buildings are quite scattered. Public blocks occupy most of the buildings that are presented. I chose to use simple fill to display all the buildings because it is much easier to identify residence from public buildings. The svg marker is not particularly useful when it comes to marking out similar features that are clustered near each other in Gombak. The lighter tones are used to symbolise buildings, so as to contrast and provides clarity. For clinics, garage and construction, i used the colour thought to be afflicted with what they are. There are other unknown buildings that are unclassfied.

Gombak's natural features - showing the study area and the target natural features

Gombak's natural features.jpeg

Description: For Gombak's dwellers, families with children may visit the playground and parks, residents from all walks of life will also utilise the bukit batok town park. Waterbodies are universally recognised as blue, hence blue was used. Forests is usually seen as green, parks consists of flowers, shrubs that appears greenish, but lighter. These are also important as they are populated with not only humans at certain days of the week, but also animals and are precious natural resources of singapore. Further analysis will be conducted to determine if they need to be relocated or considered for the building of the centre.


Digital Elevation Model of Gombak - showing the study area and the digital elevation model

Gombak digital elevation.jpeg

Description: The digital elevation model shows gombak in the raster mode, where it is categorised into different colours.

Part 2: Map Layout with four views (Proximity)

Gombak Road - showing the study area and proximity to target roads (For Accessibility factor)


Proximity to roads of gombak.jpeg


Description: The legend of Proximity map layer indicates that the furthest distance from the roads is 742 metres. Particularly, we are concerned with service and tracks roads, as these are the roads that will be used to transport materials during the construction stage in the building phase. There are 199 service roads and only 2 tracks. Blue indicates zero proximity while red indicates the furthest range of distances, which is not ideal for transportation. Accessibility factor is determined by the shortest distance of the quarantine centre location to enable effective delivery of building materials. I defined it as less than or equal to 200m, the same numerical value used in class. It is relatively easy for a nearer vehicle to park if closer proximity is not possible. It will facilitate transportation easier as the workers do not have to travel too far by walking from their vehicle.


Gombak Buildings - showing the study area and proximity to buildings (For Health factor)


Proximity to buildings of gombak.jpeg


Description: The legend of Proximity map layer indicates that the furthest distance from the buildings is 825 metres. The health risk posed by the national communicable disease centre should not be undermined. As it houses patients who are infected with diseases. These diseases may be transmitted by air or water. The contagious disease will be harder to quarantine in the event should it happen. Therefore, the further the centre can be built, the better it will be for the healthy population.


Gombak's natural features - showing the study area and the proximity to target natural features (For Natural conservation factor)

Proximity to natural features of gombak.jpeg


Description: The legend of Proximity map layer indicates that the furthest distance from the natural features is 1015 metres. Under natural conservation factor, we identified pavilion, Bukit Batok parks, forested land. There are 1 major park, 1 forest and 1 waterbody. A minor reason is for aesthetic purpose. It is to preserve the beauty and scarcity of the remaining natural features, as well as the animal biodiversity that is present in forest and parks.


The slope of Gombak - showing the study area and the slope (For economic factor)

Slope of gombak.jpeg


Description: The legend of Slope layer shows that the minimum and maximum values of the slope values are 0 and 34.3 degrees respectively. Under economic factor, it is regarded to be more costly if the centre were to be built on a steeper slope, rather than building on a flat slope. With a sharp inclination, it is also impossible to build. Hence, an ideal slop inclination is less than 15 degrees. The blue regions are the best to build the centre when the centre is cheap to build. The red regions are not ideal for building and urban planners, developers are advised not to target these places.

Part 3: May Layout with four views (Criterion Scores)

After standardising the scores to 0-1 using min-max method, the best score is 1, where it is the most ideal and represented by blue. The worst score is 0, where it is represented by red. After using the analytical hierarchal processing matrix, the consistency index and consistency ratio had obtained a validity pass and the weightage assigned to the scores were used with the spatial overlay to obtain the criterion layer.

Description: 1)Economic factor

Economic score.jpeg

Economic factor: The selected site should not be steep. As such, we define steep slopes as those more than 15 degrees. I have decided to place a value of 1, as the base value that i would compare other factors with. I regarded it as the least important among all the factors because the costs of building the quarantine centre is less prioritised although building on a steeper slope incurs more money to build than if it were to be built on a flatter land. The economical costs of the consequences cannot be overlooked if the centre were to be built near population or communal areas where lives are at risk.

2) Accessibility Factor

Accessibility score.jpeg

Accessibility factor: The selected site should be close to existing local roads, namely: service roads and tracks. This is to ensure easy transportation of building materials during the construction stage. The estimated ideal distance is less than 201m. I chose an importance value of 3 because it is slightly important to transport healthcare neccessities, food and it is convenient to send building materials during the construction stage. This is least of concern among all factors because it benefits the construction workers and relevant people during the building stage, but will not be as important as the others after construction. fast accessibility by travelling time or proximity will benefit future patients or doctors who will be staying in the centre for long periods of time. The distance should not be neglected as convenience in travelling to important amenities is a criteria for good liveability in smart cities.


3) Health Risk Factor

Health score.jpeg

Health risk factor: The selected site should be away from population i.e. housing areas and offices in order to avoid disease spreading to the nearby population. The communicable disease centre will be infectious and hence, it has to be built in a region notwithstanding 10000msquare. I defined that as a rectangular area where the centre is located in the centre of the area boundary. I determined the euclidean distance as the midpoint of a square where it bisects the area and distance is halved. This factor has been assigned the highest weightage among all the factors and forms the main reason to support the isolation of the centre, it also poses high risk for visitors and surrounding lifeforms, such as people and animals that are present nearby.


4) Natural Conservation Factor

Nature score.jpeg

Natural conservation factor: The selected site should be away from forested land, park and water. Since diseases are transmitted by aquatic means, the communicable disease centre should also not be located near waterbodies or parks as waterbodies can be a vessel for diseases, parks are patronised by citizens from all walks of life,so the centre should not be near them as well. Hence, it has to be built in a region notwithstanding square. This factor is given a secondary importance, because it cannot be overlooked. It is costlier in the future to tamper with nature as it is scarce to begin with. Nature takes time to rehabilitate. It also costs another sum of money to remove the trees. Biodiversity and nature conservation of Gomak should not be overlooked, thorough thoughts should be given in deciding to build the centre in substitution of the trees.

Part 4: Analytical Hierarchical Process Input Matrix

Screenshot 2019-11-05 at 11.04.56 AM.png

Data Source: AHP Template from SCBUK (XLS)


Part 4.1: Analytical Hierarchical Process Result Report

(1) For economic factor, I assigned 1, as the base value.

(2) For accessibility factor, i assigned 3 because it is slightly important.

(3) For health factor, i assigned 5, it is the most important.

(4) For nature factor, i assigned 4, of secondary importance.

The pair-wise comparison matrix and its relative importance to each other factors have been computed. They are 0.076, 0.239,0.381,0.304. These are then used to determine the consistence index (CI).

Consistency index is 0.01398781. Since the number of factors used in the decision making is 4, the corresponding value is 0.9, according to the randomness index scale. This is the randomness index (RI).

The final consistency ratio (CR) is then found by calculating the division of consistency index value and the randomness index value. CR is 0.015542014.

Since CR<=0.1, the consistency score shows that the judging criterias have a reasonable level of consistency.

Part 5: Map Layout (Suitability)

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The weighted overlay analysis is used where different weightage for the four factors are computed and combine with the criteria maps to produce the land suitability map. The multi-criteria decision making might be prone to errornous judgement, as experts are not exempted from this either. Thus, AHP uses a pair-wise comparison matrix to show the criterias given to health, nature, accessibility, economic factors. The multitude of these factors are of different importance, with relative weights assigned to each of them. Highest weightage is assigned to health risk and lowest weightage is given to economic cost of building the communicable disease quarantine centre. All criterion layers are assessed to show regions of Gombak in a standardised scale from 0-1. The region that make the cut will be those that scores more than 0.5, which is the green and blue regions. From 0 being an unsuitable choice, to 1 representing the most ideal choice. In this analysis, i regarded the existing features that would be hard to revamp, and modifying would require reconstruction and removal of the present infrastructure or natural features. Using the measure area tool, I picked the best region that fit the criteria of having a 10000metres square quarantine area and is the best place to build the quarantine centre.

The equation i used in the raster calculator is ( "criterion slope economic @1" *0.076 ) + ("criterion roads accessibility@1" * 0.239) + ("criterion buildings health @1" * 0.381)+("criterion nature natural conservation@1" * 0.304)


Data sources for pictures, images,ahp template, understanding of ahp and land suitability analysis. https://data.gov.sg/ https://download.bbbike.org/osm/bbbike/Singapore/ https://search.earthdata.nasa.gov/search?m=-7.175!25.59375!1!1!0!0%2C2 http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.468.4502&rep=rep1&type=pdf https://www.diva-portal.org/smash/get/diva2:648067/FULLTEXT01.pdf