Mathematical analysis of a chaotic model in relevance to monsoon ISO

Mathematical analysis of a predominantly bimodal chaotic attractor, Lu system, was carried out to investigate a possible application of the model as a prototype of monsoon intra-seasonal oscillation (ISO). Bifurcation structures of the system are explored as the system parameter c and the forcing parameter F are varied. Stability criteria of equilibrium points of the forced Lu system are also explored in detail. A sensitivity study is carried out, by changing forcing parameter F, to explore relationships between some of the derived variables of the model and, based on such relationships, an empirical rule is used for extended range prediction. Analogous variables are also derived from the ISO data and prediction results are compared. Application of the prediction rule of regime transition to the observed ISO and chaotic model data is purely based on the bimodal characteristics of ISO and neglects some of the intricate mechanisms therein. We have found that a forced Lu system can be a good prototype in the prediction of peak anomaly of the monsoon ISO when growth rates around a threshold value are taken as predictors.     

Analyses of fold profiles by changing weight parameters of NURB curves

Analyses of Non-Uniform Rational B-spline (NURB) curve by varying weights at its nodal points and projection ratio produce several kinetically plausible symmetric and asymmetric fold morphologies in 2D promptly and efficiently with varied overall geometries, curvature of limbs, sharpness/bluntness of hinges, extent of hinge zone, tightness/interlimb angles, etc. Some of these folds are new geometries what other approaches, such as those with Bézier curve, did not produce so far. Natural fold profiles can be matched with NURB curves from photographs.     

Airy’s isostatic model: a proposal for a realistic case

This work derives algebraic expressions for Airy-type isostatic equilibrium and disequilibrium of lithospheric blocks within asthenosphere, considering a more realistic case of continuously varying densities of the lithosphere along mutually perpendicular directions. Isostatic (dis)equilibrium must be linked to the porosity and density of the rock matrix, and to pore fluid density since these factors govern the bulk density of wet sediments/porous rocks. Two combinations of exponential and linear increase of density with depth are demonstrated. Isostatic disequilibrium would speed up sinking/uplift of the lithospheric blocks. Given any other (empirical) equations for density variation in three perpendicular directions, isostatic (dis)equilibrium such as Eqs. 14, 17, 18, 28, and 29 can be theorized as well.     

Proposed Adsorption–Diffusion Model for Characterizing Chromium(VI) Removal Using Dried Water Hyacinth Roots

Experiments have been carried out to characterize the adsorption of chromium(VI) in the aqueous phase onto dried roots of water hyacinth. Results revealed a very high degree of removal efficiency (∼100%). Theoretical analyzes are also made for describing the sorption and diffusion processes. The effective pore diffusivity of chromium(VI) in the water hyacinth roots is determined by a suitable global optimization technique. The depth of penetration, on the other hand, has been estimated for various initial concentrations of chromium(VI). Theoretically predicted concentration profiles are in excellent agreement with the experimental values.     

Geologic,geomorphic and hydrologic framework and evolution of the Bengal basin,India and Bangladesh

The Bengal basin, the largest fluvio-deltaic sedimentary system on Earth, is located in Bangladesh and three eastern states of India. Sediment accumulates in the basin from the Ganges, Brahmaputra, and Meghna (GBM) river systems and is dispersed into the Bay of Bengal, forming the largest submarine fan in the world. The basin is located in the Himalayan foreland at the junction of the Indian, Eurasian, and Burmese plates. The basin is bounded by the Indian craton on the west and the Indo-Burmese fold belts on the east. It can be broadly divided into a stable shelf and a foredeep separated by a deep seismic hinge zone. Basin sediments overlie Gondwanan basement and vary in thickness from a few kilometers on the stable shelf to more than 16 km in the foredeep. The basin was initiated at the breakup of Gondwanaland in the late Mesozoic and evolved through the formation of the proto-GBM delta to the present delta starting around 10.5 Ma. The stratigraphy of the different parts of the basin differs considerably, because of contrast in depositional history within the several sub-basins that were produced by intra-plate tectonic activities associated with ongoing Himalayan orogeny. The present-day geomorphology is dominated by the extensive Holocene GBM floodplain and delta. The vertical succession of the deltaic plain can be classified into five units on the basis of differences in grain size, which reflect differing depositional environments. The initiation of the modern GBM delta at the onset of the Pleistocene glacial maximum and its evolution to the present configuration are intricately related to Holocene fluvio-dynamic processes, eustatic sea-level changes, and tectonic movements.The sedimentology and mineralogy of the different parts of the basin reflect differences in sediment provenance. The mineralogy is dominated by detrital quartz, some feldspar, and minor amounts of carbonates; illite and kaolinite are the main clay minerals. The basin has profuse groundwater resources, but the architecture of the aquifers is not yet well resolved. Different classification schemes have been proposed on the basis of lithology. Regional groundwater flow follows a low hydraulic gradient from north to south, but pumping for irrigation during the past several decades appears to have severely distorted regional flow. Recharge occurs primarily during the monsoon season. Groundwater chemistry is dominated by anoxic, Ca–HCO₃-type water with relatively high concentrations of Fe, Mn, and As. Carbonate dissolution, silicate weathering, FeOOH reduction, and mixing with saline water are the primary processes controlling hydrochemistry.     

Microzonation of seismic and landslide prone areas for alternate highway alignment in a part of western coast of India using remote sensing techniques

West coast of India is a narrow and linear, a portion from Bombay to Goa in this track is known as Konkan coast. Remotely Sensed geocoded data from IRS-1B has the potentiality in identification of localized patches of change in environmental parameters, which includes changes in lineament pattern, vegetation anomaly, rock debris and occurrence of landslides. Ground protuberances in this terrain are important surface manifestations of probable seismic activity. In these areas quaquaversal drainage pattern is inferred. Landslides are also expected in places near NH-17 (National Highway — 17) which may affect the socio-economic scenario of area. Alternate highway alignment is planned based on least hazard potentiality of the terrain. Weathered Basalts inferred, near the bank of Amba river, were not recommended for tunnel construction. Anomalous clay patches need more care for road construction. Inferred joints, fractures and faults were found in some places which were marked as hazardous locations. Some areas were marked hazardous for road construction due to the presence of palaeochannels but the same were marked as potential areas for ground water exploration.     

GSC 45401533: Observations and Analysis of a NewlyDiscovered Binary Star

R observations of a newly discovered binary GSC 4540_1533 are presented. Analysis of the light curve with the Wilson-Devinney program indicates that the system is detached and consist of 2 main sequence stars. This revised version was published online in July 2006 with corrections to the Cover Date.     

A multi-layered backpropagation artificial neural network algorithm for UV spectral classification

In this paper we present an application of an artificial neural network model based on a multi-layered backpropagation algorithm for spectral classification of UV data from the International Ultraviolet Explorer (IUE) low dispersion spectra reference atlas. The model used is similar to that of von Hippel et al. (1994), and is found to reduce the classification error as compared to the recently reported results on the same data set (Gulati et al. 1994b). The improved version of the network is much simpler in structure and the training time is reduced by a factor of almost 20. Such networks will prove very useful in efficient classification of large databases Subject headings: neural networks, stellar spectra, classification     

Effect of canal on land use/land cover using remote sensing and GIS

The monitoring of land use/land covers (LULCs) is an indispensable exercise for all those involved in executing policies to optimize the use of natural resources and minimize the ill impacts on the environment. The study here aims at analyzing the changes that occurred in LULC over a time span from 1990 to 2005 using multi date data of a part of Punjab. The digital data consisted of two sets of Landsat Thematic Mapper (TM) data and one set of IRS-1C data. Utilizing hybrid classification technique for interpretation and on field validation, it has been found that canal irrigation leads to changes in LULC as there is a change in cropping pattern as well as increase in water logged area.