Remote Sensing

Digital elevation model (DEM) is used to determine the drainage networks involving the size, length, slope and similar features of the basin and sub basin features related to the water resource. Most importantly the hydrological analysis to be effective if the slope, area, direction, flow length, runoff length could be better reached through DEM. Scattered hydrological models clearly suggest the spatial variability of the physical properties of the basins. In this study, the characteristics of the Kottakarai Aru water shed located in Ramanathapuram district nearer to the Bay of Bengal are explained through the digital elevation model (DEM)for a detailed study of the drainage networks.

Well-2 of Koko field was drilled as an exploratory well, and various analytical tests aimed at determining the petrochemical characteristics of the reservoir sand, was utilized in the evaluation of the hydrocarbon prospect of the area. The gamma ray log, resistivety/inductivity log, compensated neutron were used in getting the above information, through the identification of the various lithologic units present in the well. From the information got from the various logs, it can be inferred that the hydrocarbon prospect of the area is low at the present depth of investigation.

The structural and tectonic analysis of Okposi and environs, Lower Benue Trough using Landsat-TM data was carried out with the aim of carrying out a detailed structural interpretation of the study area by identifying the lineaments associated with the study area and inferring their effect on the economic potentials of the study area. In addition, this study was aimed at determining whether the Okposi Brine Lake in the study area is structurally controlled. Several GIS softwares which include the ILWIS 3.1 Academic were used to analyze the data. Simple digital image processing techniques were applied on the data to enhance edges of linear features, followed by computer aided visual interpretation. Results revealed that high lineament frequencies/density were obtained in areas where basement rocks outcrop or are closer to the surface whereas low lineament frequencies are characteristics of areas with deeply buried basement rocks. Similarly, the absence of visible lineaments in parts of the area may not be indicative of complete absence of geological structures. Trend analysis of the lineaments computed by plotting the strikes and lengths of all the lineaments revealed on the image on a rose diagram revealed structural trends in the E-W, N-S, NW-SE and NE-SW directions with the NW-SE and NE-SW directions as the dominant trends. The NE-SW linear structures observed from the study are believed to be the continental extension of the known pre-Cretaceous trans-Oceanic Fracture Zones viz. Charcot and Chain Fracture Zones. The numerous lineaments in the study area make the region viable for mineral prospecting. Finally, the presence of a lineament zone around Okposi area may be responsible for the formation of the Okposi Brine Lake. It is believed that this linear feature must have cut through the basinal brine of the Asu River group of the Benue Trough.

Wetlands are one of the most important aquatic ecosystems that play a significant role in modifying the quantity and quality of water, providing economic and tourist opportunities as well as drinking water and livelihood for aboriginal people. Establishing and maintaining a suitable water regime as well as wise use of wetland ecosystems in such a way to preserve their functions and values are considered as the most important management issues in wetlands. The basin of the Parishan International Wetland is located between 51° and 44' and 51° and 51' of east longitude and 29° and 32' and 30'' of north latitude of Fars province. The purpose of this study was to evaluate the hydrology and determine the environmental abonne of Parishan Wetland to preserve and rescue this international wetland. Aiming at this goal, remote sensing techniques and the data recorded by related organizations were used. The results of the study showed that the currents of water entering the wetland over the solar year of 1380 consisted of runoff (20.06 million cubic meters), rainfall (14.75 million cubic meters), springs (5.487 million cubic meters) and groundwater leakage to the wetland (34.663 million cubic meters); the output of the wetland was also subject to evaporation (85.1 million cubic meters). Also, the amount of ecological water required by the wetland is equivalent to 110.96 million cubic meters.

In this paper, the application of the fully automated road detection for high resolution panchromatic images is proposed. This approach includes image binarization, boundary tracing algorithm and mathematical morphology reconstruction in order to retrieve main regions which have high potential to be regarded as road. Fuzzy C-means clustering is used for image binarization. Moore-Neighbour tracing algorithm modified by Jacob's stopping criteria is applied for tracking and labelling regions then flood-fill algorithm is exerted on regions in order to fill holes. Afterwards, four main shape-factors are introduced which can effectively discriminate between road and other terrain features. The R, H, Q and C factors that are relevant to shape of road are defined in this research. K-means cluster is then utilized to separate the roads from others, based on mentioned shape-factors. The algorithm has been tested with PANchromic (PAN) image of Worldview2 sensor. The results demonstrated development in road detection based on shape-factor clustering.

Landslide is among the major hydro-geological hazards that affect large part of India, especially Western Ghats and Eastern Ghats. The paper presents an integrated GIS and Remote sensing approach for Landslide Hazard Zonation in part of Sirumalai hill, Tamil Nadu. Satellite data, topographic maps, field data and other information maps are used to the study were prepared in GIS environment. Numerical rating scheme for the factors was developed for the spatial analysis in GIS environment to arrive at landslide Hazard Zonation map of the area. Landslide Hazard Index (LHI) value is calculated and landslide hazard zonation is decide by the LHI histogram. The resulting of the landslide Hazard Index Frequency Mapping is classified in five classes: very high, high, moderate, low, very low. Field data on landslide bodies are used to evaluate and validate the LHZ Map.

Ad Hoc Network provides quick communication among knob to convey the packets from one knob to other. These networks are independent of any fixed infrastructure or central entity like cellular networks [10] which requires fixed infrastructure to operate. Any malicious knob in the network can disturb the whole process or can even stop it. Several attacks like Replay attack, black hole, wormhole, rushing etc [13], in which legitimate knob behaves like malicious knob and disturbed whole the network. To define and detect the malicious behavior of a knob, it becomes obligatory to define the regular and malicious behavior of a knob. Whenever a knob exhibits a malicious behavior under any attack, it assures the breach of security principles like availability, integrity, confidentiality etc [13].

The present study area (Cauvery river basin) lies between 77o 43’ 54’’ E to 79o 35’ 55’’ E longititude and Latitude 10o 10’ 0’’ N to 11o 10’ 6’’ N. The basin area is demarcated from the survey of Indian topographical map No.58 I/2 (1:50,000,1972) and it covers the area about 3397 sqkms. Morphometric analysis and their relative parameters have been quantitatively carried out for the Cauvery basin, Salem district, Tamilnadu, India. Digital elevation model (DEM) is used to determine the features of drainage networks and slope of drainage network and to determine the characteristics of basins. The foregoing analysis clearly indicates some relations among the various attributes of the morphometric aspects of the basin helps to understand their role in sculpturing the surface of the region.

This paper investigates the effects of extra-terrestrial impact cratering of Silali Basin on the environment of the area. The Silali Basin is located in Turkana East /Pokot East regions of Kenya. The basin is a depression suspected to be an extra-terrestrial impact crater (ETIC). The objective of the study was to document the effect that the cratering of Silali had on the environment of the area. To answer the study research question, remote sensing was utilized to map the Silali basin. Satellite images were used to identify the nature of the crater and characterize it, since most large terrestrial impact craters are not identifiable from the surface of the earth. The study established that the effects of Silali’s impact cratering on the environment of the area include formation of physical features and minerals. The crater’s potential economic and social significance has also been cited and include tourism, paragliding, quarrying of breccias and geothermal power harvesting. Being a pioneer study in the investigation of ETICs in Kenya, the study may form a basis for further research on ETICs in the country, besides enhancing knowledge on Extra-terrestrial impact cratering in Kenya and its environmental significance. It is also hoped that the study will enhance the economic utilization of Silali basin.

Human activities such as development of urban area and reducing vegetation cause dramatic changes in surface runoff generation. In the present study effects of Land use and Land cover (LU/LC) changes on surface runoff in Siahroud watershed in north of Iran has been assessed. LU/LC was derived from an Aster imagery (acquired in 2002) and a Landsat 8 imagery (acquired in 2013) for two different periods using object-oriented classification. For this purpose preprocessing and Image enhancement on remotely sensed data were applied. The images were segmented to objects and then objects assigned into 5 classes based on spectral features and physical characteristics such as texture and size of the segmented objects. Accuracy assessment of Classifications was computed by calculation of total accuracy for each classification, user, producer`s accuracy for individual classes and also KAPPA index. In order to determine the average Curve Number for each year, LULC maps were combined with Soil Hydrologic Groups map of study area in ArcGIS. The surface runoff was calculated for 7 events in each year using SCS-CN method. Finally direct runoff has been calculated from the same rainfall for both years. Results showed that urban area has increased during the last 11 year resulting in 5to 40 percent increase in surface runoff.