Remote Sensing of Sea State by the Brewsters Angle Technique

The extent of plane polarised light resulting from Brewsters reflection from the wide-roughened sea surface is studied for various sea states on the assumption that the incident light on the air-sea interface is unpolarised. The sea states associated with different wind speeds are simulated using the Cox and Munk 'wind speed-wave slope' law and the Gaussian distribution of wave-slopes. The spatial distribution of plane polarised component of diffuse reflected light is also studied with a view to exploring possibilities of using this parameter for remote sensing of sea state from a sensor viewing the sea surface through an appropriate polaroid. The results show that the plane polarised fraction of reflected light as received in a given look angle can be directly related to the prevailing sea state and can be used as a convenient parameter for remote sensing of sea state. The scope and limitations of the method proposed are discussed

ENERGY AUDITING OF A HOUSE USING MATLAB

Energy crisis is one of the crucial problems faced by all the countries in the world due to depletion in natural resources used for energy generation and the huge investment for generating energy from alternate resources. This article shows the present situation of energy crisis in the state of Andhra Pradesh and suggested some of the major areas of energy conservation practices so that there may be a chance to see the state of Andhra Pradesh as “NO POWER CUT” state in India. A viable and immediate solution in this juncture is the energy conservation as cited by the slogan “Energy conserved is Energy Generated”. Optimum use of electrical energy, not only results in cash savings, but also improves the economy of the country substantially. Hence there is an urgent need for energy management and control, which ultimately concludes with the practice of energy conservation. Energy as we all know is a crucial input in the process of economic, social and industrial development. Energy consumption is increasing at a very fast rate. With growing demand for energy it has become essential to minimize energy leakages. This article shows the present status of energy crisis in “Andhra Pradesh” state. This article also shows about the gap between power generation and demand and it suggest some of the methods to make the gap between power generation and demand is equal to Zero

Problems and Perspectives of Health Sciences Libraries in Digital Era : A Descriptive Analysis with Sepcial Reference to Karnataka and Maharastra

The ~resent study on health science libraries in «ernetsk« and Mat:arastra indicate that libraries in India have to go tonq- way 10 become IT based knowledge system or to call as Digital Libraries or Virtual Libraries. The development, as it goes in India. to achieve iotcqrsteo information services, on par with the capability of health care services. would remain as a dream. Majority of the libraries as per the study are concentrating on legacy system both in evaluation of inlormation services/resources in medical colleges and they are.yet to Change their mindset towards this transitional effect in the application of IT

Influence of Bathymetry on the Performance of Regional Scale Model

 A three dimensional ocean circulation model (Princeton Ocean Model) is utilised to study the thermohaline variability of the eastern Arabian Sea associated with changes in the three input bathymetry data sets, viz. ETOPO5 (E5), Modified ETOPO5 (ME5) and ME5 further modified based on actual fine resolution data collected using Multibeam echo-sounder (MEN5). The temperature and salinity measurements made onboard INS Sagardhwani for the period July 2000 is utilised to validate the model. Simulations of temperature using Princeton Ocean Model show good improvement in the coastal region with MEN5 bathymetry data (RMS error of 0.71 °C and correlation coefficient of 0.98). The study highlights the choice of fine resolution bathymetry data in the simulation of nearshore processes, where bathymetry is very complex

Transmission Loss Variability Associated with Upwelling and Downwelling Off the Southwest Coast of India

Fine resolution spatial survey carried out off the west coast of India during June and December 2004 was utilised to study the transmission loss (TL) variability associated with the upwelling and downwelling processes in this region. During June, the upwelling was confined to the upper 80 m. Downsloping of isotherms below this depth towards the coast and the occurrence of low saline waters indicated the presence of undercurrent. Between the periods of upwelling and downwelling, temperature and salinity in the surface layers increased by 1-2 oC and 2 PSU, respectively, while at the sub-surface levels, the corresponding increase was ~8 oC and ~0.5 PSU. A range-dependent acoustic propagation model based on parabolic equation method was utilized to compute TL for these two periods. The model was run with a source frequency of 3 kHz kept at 5m depth for different environmental setup, viz. propagation along the constant-depth contour, range-independent and range-dependent environment, and upslope/downslope propagation. The computations revealed significant variability in the TL characteristics between the upwelling and downwelling scenario, though bathymetry and geo-acoustic properties were the same. The analysis also stressed the need of range-dependent acoustic propagation model for realistic prediction of transmission loss variability.Defence Science Journal, 2010, 60(5), pp.476-482, DOI:http://dx.doi.org/10.14429/dsj.60.57

On the Possible Mechanisms for Saltening of the Bay of Bengal

The Bay of Bengal (BoB) is a low saline basin owing to large influx of freshwater from precipitation and river runoff. To maintain the salt balance of the BoB, the incessant lowering of salinity is to be balanced by the inflow of saltier water into the basin. In the present work, various processes that contribute to the saltening of the BoB, viz. coastal upwelling, eddies and their interaction, lateral advection from Arabian Sea and tropical cyclones are discussed. In the near-shore regions, the coastal upwelling due to wind induced Ekman transport plays a dominant role in increasing the surface salinity. On the other hand, in the open ocean, the divergence induced by eddies and their mutual interaction contributes significantly to the salt water pumping. In the southern BoB, the advection from the Arabian Sea increases the salinity. The formation of cyclones in the BoB also leads to an increase in the surface salinity. However, the magnitude of saltening of the Bay due to these processes varies from north to south. The uplift of saltier water from subsurface levels increases the salinity in the surface layers thereby creating a salinity gradient and a salinity front

Evaluation of Modal Damping in FRP based Laminated Composites through Modal Testing

The main source of damping in laminated composite materials arises from the inelastic nature of the matrix and the relative slipping at the fiber/matrix interfaces. Damping in laminated composite materials is usually a function of many parameters including the volume fraction of the fibers, fiber diameter and fiber orientation relative to the axis of loading.Also the magnitude and frequency of the applied load and many environmental factors should be mentioned. Since the complex phenomenon of damping is difficult to incorporate into the structural dynamic analysis of laminated plates, a modal damping approximation is employed here. Various methods have been presented to obtain the modal damping of a laminated composite.In this paper, classical modal testing of bi-woven laminates under various boundary conditions and analysis of the damping is carried out. Laminates made of Glass and Graphite fibers with epoxy resin as matrix is used in modal testing. Traditional “Strike Method” is adopted which consists of impulse hammer and accelerometer with 4-channel FFT analyzer to obtain the response of the specimen under test. Results obtained from both laminates are compared and it is observed that damping properties of graphite is more dominant than glass laminates

Shallow Water Internal Waves and Associated Acoustic Intensity Fluctuations

Physical oceanographic and acoustic data were simultaneously collected from the coastalwaters of the Arabian Sea. Acoustic transmissions were carried out from an anchored vesselusing 620 Hz transducer and received by an array of hydrophones moored at ~5 km away fromthe anchorage. Thermal structure in this region was characterised by a tri-layer structure, ie, astrong thermocline (> 0.4 oC/m) sandwiched between an upper (< 10 m) and bottom (> 25 m)homogeneous layer. High-resolution (sampled at 10 s interval) temperature data from mooredsensors revealed intense internal wave activity. The maximum value of Brunt-Vaisala frequency,which is the maximum frequency limit of internal waves in the thermocline, suggests that theupper frequency limit of the internal wave, which can be generated during this period, is 23 cph(2.6 min). High and low frequency waves caused variations of ~3 oC and ~5 oC respectively inthe temperature field. But the low frequency internal waves were found to contain maximumenergy compared to the high frequency waves. Fluctuations of 8-12 dB were noticed in themeasured acoustic intensity values in the presence of low frequency internal waves. Simulationstudies carried out using parabolic equation model using 620 Hz source indicated well-definedducted propagation with minimum transmission loss, when the source was kept within thehomogeneous layer. The presence of tri-layer thermal structure, ie, a strong gradient layersandwiched between an upper and bottom homogeneous layer, caused surface and bottom channelpropagation in this region

Multiple Feature Fuzzy c-means Clustering Algorithm for Segmentation of Microarray Images

Microarray technology allows the simultaneous monitoring of thousands of genes. Based on the gene expression measurements, microarray technology have proven powerful in gene expression profiling for discovering new types of diseases and for predicting the type of a disease. Gridding, segmentation and intensity extraction are the three important steps in microarray image analysis. Clustering algorithms have been used for microarray image segmentation with an advantage that they are not restricted to a particular shape and size for the spots. Instead of using single feature clustering algorithm, this paper presents multiple feature clustering algorithm with three features for each pixel such as pixel intensity, distance from the center of the spot and median of surrounding pixels. In all the traditional clustering algorithms, number of clusters and initial centroids are randomly selected and often specified by the user.  In this paper, a new algorithm based on empirical mode decomposition algorithm for the histogram of the input image will generate the number of clusters and initial centroids required for clustering.   It overcomes the shortage of random initialization in traditional clustering and achieves high computational speed by reducing the number of iterations. The experimental results show that multiple feature Fuzzy C-means has segmented the microarray image more accurately than other algorithms