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Proper pipeline route selection is an integral component of a typical oil exploration and transportation project. Improperly selected routes could have severe consequences including pipe failures, oil spillage, and environmental disasters. Consequently, technologies like geographic information systems (GIS) are increasingly being used to facilitate the oil pipeline route selection procedure—especially for onshore routing projects. Surprisingly, not much has been documented on the application of GIS to offshore pipeline routing. With recent discoveries on the merits of offshore oil exploration, it is necessary to extend the analytical capabilities of GIS to the unique offshore domain. However, concerns have been raised regarding the limitations of GIS in accurately prioritizing diverse selection criteria in typical multi-criteria decision-making (MCDM) problems like route selection. Consequently, this paper addresses the offshore/subsea pipeline routing constraint using a hybrid decision support sy...

A Geospatial Technology-based Group Analytic Hierarchy Process (GAHP) was carried out to forecast the likely flooded areas based on a total number of five set of criteria/factors believed to be influencing flood generation in the study area. The GAHP is based on two categories of experts (hydrologists and geologists). Priority weights were assigned to each criterion/factor based on Saaty's 9 point scale of preference by the experts and weights were further normalized through the AHP. The ranking given by the two experts were further integrated into GIS environment to come up with the flood forecasting map for the area. These results were further validated using the known Flood Extent Extraction Model developed based on a Minimum Distance Algorithm embedded in ENVI 4.8 software and the Consistency Ratio (CR). Image overlay was carried out in ArcGIS 9.3 software of the two results with the known Flood Extent Extraction Model developed herein. The ranking given by the hydrologists demonstrated a high degree of correlation compared to what is on the ground.

Understanding the surface and subsurface condition can immensely enhance the availability of accurate flood susceptibility maps for effective management of flood catastrophe. In this study, remote sensing and Geographic Information System-based (GIS-based) Multi-Criteria Decision Analysis (MCDA) based on experts' opinions has been adopted to carry out the preparedness phase of flood management. Establishing a link between the surface/subsurface conditions and flood occurrence is the major objective of this study. The surface/subsurface investigations showed that the lowland areas of the study area are characterized by the presence of flat slope, alluvium deposits and low humid clay soil composition. The GIS-based Analytic Hierarchy Process (AHP) model was adopted in simulating the flood susceptible zones map of the study area. Finally, the result revealed that flood generation in the area immensely relied on slope, geology and soil type along with rainfall as the key catalyst.

Geographic Information System (GIS) was integrated with Group Analytic Hierarchy Process (GAHP) to facilitate the simulation of flood likely areas based on a total number of five set of criteria/factors believed to be triggering flood generation in the study area. Two categories of experts namely hydrologists and geologists were considered. Saaty’s 1-9 scale of preference was employed in rating each factor’s influence in flood generation and the ratings from the experts were aggregated using a Geometric Mean method. Having done with the aggregation, priory weights of the factors were calculated; weights were further normalized through the Analytic Hierarchy Process (AHP). The result was further integrated into GIS system for spatial simulation of the likely flood areas. The result forecasted 39.1% of the total area to be very highly susceptible to flooding. Validation was carried out by superimposing the known flood extent map from radar satellite data over the flood forecasting model developed herein.

This paper presents the preliminary work is a part of a research focusing on close range photogrammetry for landslide monitoring.The main objective of this paper is to present the Close Range Photogrammetry (CRP) technique, Unmanned Aerial Vehicle (UAV) will provide a platform to monitor the surface area This method was applied using the capabilities and power of Gatewing, Unmanned Aerial Vehicle (UAV) for data capturing with respect to UAV tracking conducted in UTP, Tronoh, Perak, on 15th March 2012 at 150m height. The Gatewing is designed for rapid terrain mapping with fully automated image processing. The result proves that data processing were conducted by Srecthout Software. Flight planning was carried out on site, where the areas to be observed are situated inside the UTP campus. The paper focus on final production of an orthomosaic. In conclusion, it is demonstrated that Gatewing, UAV is the best, fast and powerful mapping vehicle for close range photogrammetry application in future works. It shows highly excellent performance compared to other UAVs already established in the market today. Keywords: Unmanned Aerial Vehicle (UAV); Close Range Photogrammetry (CRP); Gatewing; orthomosaic; terrain.

Information and communication technology, which has been incorporated and provided in the Geographic Information System (GIS), is valuable and effective geospatial information for the decision makers in improving their decisions in planning and development. The integration of this GIS using the multicriteria decision analysis approach provides an environment to the decision makers in citing areas using land suitability analysis procedures. This review paper particularly examines the GIS-based analytic hierarchy process as a multicriteria analysis/evaluation technique in land suitability analysis by means of literature reviews and surveys.

There are many approaches in monitoring landslide but close range photogrammetry (CRP) provides mapping achieved almost immediately at a low cost compared with other approach.CRP is a dimension technology which is used to acquire 3D spatial information on objects in inaccessible areas. The method involves camera calibration which includes a process of finding the true parameters of the camera. The information is obtained through accurate assessment and used to create a 3D model which would be used for monitoring technique applications. In this study, calibration of the digital camera was performed using PhotoModeler Pro 5. A good calibration will have many points marked. Field observations on site survey were carried out on 6/11/2010 and 3/8/2011 over a monitoring area in Parit, Seri Iskandar, Perak. The landslide can be detected by calculation of two different epoch data achieved from Digital Elevation Models (DEMs) generation. The paper focuses on the monitoring on the studied area based on DEM area and volume generated from 3D surface analysis.

This century has continued to witness an ever increasing reliance on Geographical Information Systems (GIS) technology for the management of utilities’ pipelines world over. Underground cables and pipelines are required to transport essential utilities such as oil, gas, water and electricity from one part of the city to another. Unlike on-surface pipelines, the fact that subsurface pipelines are hidden from the naked eyes makes them susceptible to neglect and damages without being easily noticed. Such damages and consequent pipe failures often have disastrous consequences on the environment and its inhabitants. A common source of subsurface pipeline damage is the accidental cutting of pipelines by excavation workers, oblivious of the precise underground location of such pipelines. This is largely due to the fact that pertinent decisions are usually taken using two dimensional (2D) maps as reference; however, information contained in 2D maps are often misinterpreted by both field workers and professionals alike. Three dimensional (3D) maps are increasingly becoming popular due to their ability to overcome the limitations inherent in (2D) maps. They also aid the proper conceptualization of subsurface pipelines thereby making it easier to work around these pipelines without endangering them. One major drawback though is the exorbitant cost of most of the GIS packages that support the 3D modelling and visualization of subsurface pipelines. Furthermore, the advanced languages used in building many of these packages make it difficult for non-GIS experts and professionals to relate with them. Since people from diverse disciplines (without strong GIS background) need to visualize and analyze these subsurface pipelines on a regular basis, it is pertinent to develop a system capable of performing basic 3D visualization functions, in addition to being user-friendly and highly affordable. This paper discusses such a technique, utilizing open-source software.

Optimal locations for public facilities such as public parks are significant issues in the urban planning of Larkana city. Therefore, specifically, Larkana city of Pakistan is selected as the study area where the land suitability model was applied to determine suitable land for public parks. This study was carried out within the framework of an Analytic Hierarchy Process (AHP) as a multi-criteria evaluation approach by integrating it with the Geographic Information System (GIS). Decision support system software called Expert choice 11.5 was used to calculate the weights based on three alternative scenarios. Computed composite weights were inserted into the spatial analysis function of GIS and produced three scenarios of suitability maps, i.e.: (a) land availability, (b) land value and (c) population density. Hence, based on the analysis and findings made in this research, finding suitable locations using the land suitability model for future park development is highly helpful. Results can be useful in the planning of public facilities and future land use planning in Larkana city.

Nowadays, human life is being sustained by recreation and leisure, which play an important role in the human lifestyle. Urban areas with recreational facilities such as green spaces attract the dwellers to pass their leisure time in such spaces where they can enjoy the benefits of nature. In any modern university like Universitit Teknologi Malaysia (UTM), recreational activities are very important activities that can improve the quality of students’ lives and the learning environment as a whole. The recreational parks in UTM are not favourable in relation to their distances and locations from the students’ residential zones. It becomes necessary to investigate suitable locations for a new recreational park in order to encourage students’ participation in the activities of passive recreation. Therefore, this research was conducted on the UTM students with the aim of identifying whether the current recreational parks are efficient in relation to distances, locations, and facilities. Field survey has been conducted, which helped the researchers in coming up with some set of criteria. GIS tools were used in creating different datasets of the study area and the set of criteria generated were integrated into the Multi criteria Decision Process (MCDP). Pair-wise comparison method of Analytical Hierarchy Process (AHP) was used to evaluate the criterions obtained, and weightings were assigned and calculated. The results of the weightings obtained from this method finally identified the most suitable sites to locate the proposed recreational park.

Various flood influencing factors such as rainfall, geology, slope gradient, land use, soil type, drainage density, temperature etc. are generally considered for flood hazard assessment. However, lack of appropriate handling/integration of data from different sources is a challenge that can make any spatial forecasting difficult and inaccurate. Availability of accurate flood maps and thorough understanding of the subsurface conditions can adequately enhance flood disasters management. This study presents an approach that attempts to provide a solution to this drawback by combining Geographic Information System (GIS)-based Analytic Hierarchy Process (AHP) model as spatial forecasting tools. In achieving the set objectives, spatial forecasting of flood susceptible zones in the study area was made. A total number of five set of criteria/factors believed to be influencing flood generation in the study area were selected. Priority weights were assigned to each criterion/factor based on Saaty's nine point scale of preference and weights were further normalized through the AHP. The model was integrated into a GIS system in order to produce a flood forecasting map.

Serious floods have hit the State of Perlis in 2005, 2010, as well as 2011. Perlis is situated in the northern part of Peninsula Malaysia. The floods caused great damage to properties and human lives. There are various methods used in an attempt to provide the most reliable ways to reduce the flood risk and damage to the optimum level by identifying the flood vulnerable zones. The purpose of this paper is to develop a flood extent extraction model based on Minimum Distance Algorithm and to overlay with the natural flood influencing factors considered herein in order to examine the effect of each factor in flood generation. GIS spatial database was created from a geological map, SPOT satellite image, and the topographical map. An attribute database was equally created from field investigations and historical flood areas reports of the study area. The results show a great correlation between the flood extent extraction model and the flood factors.