APPLICATIONS OF NETWORK ANALYSIS FEATURES IN GIS

More often than not, we may find offices, schools, shopping markets, and other general facilities are not nearby to our homestay for our convenience. So, there is a need for a system that could provide routing analysis to provide transportation convenience to the users to reach their destinations. The objective of this paper is to work upon Network Analysis Features of Geographic Information System (GIS) to explore its various applications such as to find the shortest routes between multiple facilities (considering time as the impedance such as nearest schools, hospitals or any other facilities from the homestay. It will also look into the best possible way to transport goods or people from one place to various other regions through multiple means. The work done was based on anonymous network data, and the discussion presents the significant applications of Network Analysis in the ArcGIS software and its usefulness to assist in the transportation issue

Application of spot5 satellite image and gis for updating road network: towards building landslide spatial database

Rapid development in urbanization is usually followed by development in transportation network. As the consequence, latest developed road networks are not found on the existing topographic map. As the topographic map-derived road network is not updated in short period, it is important to shorten the map updating cycles. SPOT 5 satellite image offers a cost effective way for updating the map compared to a conventional mapping method. The image, acquired in 2005, is used for updating road network on topographic map scaled at 1:50000, sheet 74, issued by JUPEM which was derived from aerial photograph taken in 1981. The road connecting Simpang Pulai cross and Kampung Raja, Cameron Highlands, is selected due to its considerably rapid development and susceptibility to landslide. Since most landslide occurrences take place along the road, updating road map as part of landslide geo-database becomes necessary. SPOT5 image is registered into Malaysian Coordinate System, RSO, to conform to the existing registered topographic map. Both image classification and on screen digitization methods are used to extract road network feature. The latest method is applied to complement to the first one in case of facing uncertainty in image classification. The quality of extracted road network from image classification is discussed. The extracted road network is stored into landslide spatial database. In regard to landslide aspects, features such as barren land, vegetation coverage, are also extracted. DEM derived from topographic map is used to generate slope risk map. GIS analysis is performed to locate high risk areas that prone to landslide based on two criteria. Those areas having high risk slope (200-350) and occupy barren/un-vegetated land are considered as high risk area. From this study, only 0.1% of areas occupy high risk locations. Some of which is located at existing slope failure area at Pos Slim

Effect of GPS tropospheric delay Neill mapping function simplification

The mathematical modeling on the mapping function models should be revised and also simplified to improve the calculation of the GPS tropospheric delay. The zenith tropospheric delay can be amplified by a coefficient factor called mapping function to form total tropospheric delay. There are many mapping functions have been established to calculate the scale factor which can affect the total tropospheric delay. Most of the modern models have separated mapping functions for the hydrostatic and the wet part. Recently, the developed tropospheric delay models use mapping functions in the form of continued fractions which is quite tedious in calculation. There are 26 mathematical operations for Neill Mapping Function (NMF) to be done before getting the mapping function scale factor. There is a need to simplify the mapping function models to allow faster calculation and also better understanding of the models. The mapping functions for NMF models for hydrostatic and wet components are given in a form of continued fraction, whereby the elevation angle is the variable. These mapping function models have been selected to be simplified, because of their ability to achieve mapping function scale factor, down to 3 degree of elevation angle

ROUTE SELECTION AND TRADE-OFFS EVALUATION OF THE INTERMODAL FREIGHT TRANSPORTATION

Identification of optimum routes and mode of transport play vital roles in freight transport decision making. This paper presents the research carried out for the modelling and analysis of intermodal transport network. The study evaluates the trade-offs associated with different modes of freight transportation. Geographic Information System (GIS) and MATLAB were applied to design the hypothetical intermodal freight transportation network, modelling, analysis and user-interface design. An optimum route and transport mode for different pairs of origins and destinations were determined across decision objectives such as distance, time, emission and cost. The trade-offs among different modes of freight transportation were explored. Based on the assumptions of this study, the results showed that the road was the fastest mode, while waterway was not only the most costefficient but also was the most environmental-friendly transport mode in terms of carbon dioxide emission. Although the transport network of the study was small size and hypothetical, this paper demonstrates the potentiality of this methodology for analysing larger and real intermodal networks

Effects of polyvinylpyrrolidone on structural and optical properties of willemite semiconductor nanoparticles by polymer thermal treatment method

Willemite is an inorganic semiconductor material used for optoelectronic applications. The present study purposes a new polymer thermal treatment method involving calcination temperature to fabricate the willemite nanoparticles. The effects of polyvinylpyrrolidone (PVP) on the structural and optical properties of the material were thoroughly investigated. Thermogravimetric and its derivative confirmed the decomposition behavior of PVP. The minimum calcination temperature to decompose PVP was appraised at 740 °C. The FTIR and the Raman analyses confirmed the presence of organic source before the calcination process and the formation of the crystalline structure of the willemite nanoparticles after the heat treatment. The optimum PVP concentration in this study based on the FTIR results was found to be 40 g L−1. This is the minimum concentration at which the willemite nanoparticles remained pure with homogenous distribution. X-ray diffraction analysis of the PVP samples before calcination was confirmed to be amorphous, and upon calcination between 800 and 1000 °C, an α-willemite phase was obtained. The morphology and the average particle size were determined with FESEM and HR-TEM analysis. The average particle size is between 23.8 and 36.7 nm. The optical energy band was found to be increasing from 5.24 to 5.32 eV with the corresponding increase in PVP concentration from 20 to 50 g L−1. The findings in this study provides a new pathway to understand the effects of PVP concentrations on the structural and optical properties of willemite semiconductor nanoparticles as it may have key potential applications for future optoelectronic devices

Small angle neutron scattering study of a gehlenite-based ceramic fabricated from industrial waste

This paper presents a small angle neutron scattering (SANS) study of a novel porous gehlenite-based ceramic, synthesised from a homogeneous powder mixture of soda-lime-silicate (SLS) glass, α-alumina, calcite and calcium fluoride via solid-state sintering at 1200 °C. The products of sintering at single temperatures from 600 to 1200 °C are examined by X-ray diffraction (XRD). Sintering of the mixture below 1200 °C forms two intermediate phases (Na₂ CaSi₃ O₈ and Ca₄ Si₂ O₇ F₂ ). Nepheline and α-alumina are minor phases in the gehlenite-based ceramic fabricated through sintering at 1200 °C. The microstructure of the gehlenite-based ceramic is investigated using field-emission scanning electron microscopy (FESEM) and SANS at the Australian Centre for Neutron Scattering. This study also evaluated the specific surface area of the gehlenite-based ceramic (~3.0 m² cm⁻ ³) from quantitative analysis of SANS data

Sinkhole risk modeling in residential area using GIS technique

This study presents the development of an Integrated Geographical Information System (GIS), Geophysical Method and Global Positioning Systems (GPS) survey for sinkhole risk modeling in selected residential area. The sinkhole phenomena in residential area have been known to be related to geological factor, environmental and local activities. To determine the subsurface structure and also the location of sinkholes of the study area, the geophysical survey which is resistivity survey was carried out by using ABEM SAS 4000. From the resistivity survey, the area that was identified to have sinkhole was tagged using GPS coordinates through GPS survey using GPS Topcon HiPER. The above data were integrated as a GIS database. Spatial Analysis were carried out using the User Interface developed in this study from the components of ArcGIS Software which are ArcMap and ArcObjects in order to model the sinkhole occurrence risk for the selected residential area. The user interface developed in this study would be useful for those involved in planning and development of housing area and also the other land use activities so that the adverse effect of sinkhole collapse to them could be avoided

Analisis Integritas Struktur pada Anjungan Minyak Lepas Pantai dengan Data GPS

Anjungan minyak lepas pantai yang paling umum digunakan untuk eksplorasi-produksi minyak adalah anjungan tipe jaket dengan struktur yang fixed. Operasional eksplorasi-produksi tersebut dilakukan dalam jangka waktu lama pada lokasi lepas pantai yang kondisinya sangat kompleks. Berdasar hal tersebut, diperlukan suatu analisis integritas struktur yang terkait dengan adanya deformasi sehingga dapat memantau kesehatan strukturnya. Anjungan tersebut kebanyakan terletak ratusan kilometer dari pantai. Oleh karena itu diperlukan suatu teknologi pemantauan deformasi yang menyelesaikan keterbatasan saling pandang, dapat dilakukan pada semua cuaca, minimum interaksi antar pengguna, kontinyu dan otomatis. Salah satunya adalah dengan teknik Global Positioning System (GPS). Makalah ini menyajikan analisis integritas struktur pada anjungan minyak lepas pantai dengan menerapkan data deformasi dari pengukuran GPS. Dalam analisis integritas struktur digunakan data deformasi (dalam bentuk 3-dimensi pergeseran dx, dy, dan dz) yang berasal dari pengukuran GPS yang diamati pada anjungan tersebut pada dua kala pengamatan. Data pergeseran tersebut digunakan sebagai restraint di empat sendi pada dek paling atas yang terletak pada kaki penyangga utama anjungan. Hasil menunjukkan bahwa adanya nilai pergeseran pada beberapa sendi berpengaruh terhadap integritas anjungan tersebut. Adanya pergeseran pada empat sendi menyebabkan efek pada nilai translasi dan rotasi semua sendi pada dek yang lain. Nilai translasi dan rotasi membesar akibat membesarnya nilai pergeseran. Oleh karena itu disimpulkan bahwa pemeriksaan awal dari integritas struktur suatu anjungan lepas pantai dapat menggunakan input dari analisis deformasi dengan data GPS

Evaluation of landslide causative factors towards efficient landslide susceptibility modelling in the Cameron Highlands, Malaysia

Landslide is complex interactions involving various terrain parameters and caused by various causative factors, even though each of them may not be equally significant to the occurrences of landslide. Hence to produce an efficient landslide susceptibility map (LSM) it is crucial to decide whether to include all the causative factors or otherwise. This paper presents evaluation of the relative role of landslide causative factors from which an efficient landslide susceptibility model could be constructed. Ten factors are used in this study namely lithology, geology lineament, soil, road network, river/drainage, land use land cover, slope, slope aspect, curvature, and elevation. Several scenarios were used in which causative factors are used in the modeling of LSM. A number of final LSMs are produced as the result of applying the above different scenarios. From the assessment of the accuracy of the LSM produced, it could be concluded that involvement of all factors does not guarantee of producing accurate LSM. On the other hand, using only six significant factors which are soil type, distance from road (hence cut slope), proximity to river and lake and elevation produces more accurate LSM

Effect of Reference Station Configuration for GPS Long Baseline Processing

Processing of long baseline GPS data needs specific requirement. This is due to the difficulty of ambiguity resolution for this particular reference-rover long distance (above 100 km). Distance and number of reference stations are significant factors affecting the quality of network configuration. These two things have to be determined in order to have an effective design of network configuration. This will lead higher positioning accuracy and precision. This paper presents a study on the designing of some network configuration in processing long baseline GPS. A simulation is conducted to examine the influence of number and distance of GPS stations. Two permanent stations; International Global Station (IGS) and Malaysian primary GPS station, are used for the references. The data used in this simulation are obtained from GPS offshore platform. Scientific software is used for data processing instead of commercial software since the latter are limited only for short baselines processing (below 36 km). The number of the reference station enhanced the precision of the coordinate. GPS regional station such as Malaysian primary GPS should be utilized as reference in the long baseline processing. Selection of IGS stations requires consideration concerning the configuration of the network and the distance among the stations also the quality data in the day of computation