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We present a numerical study for Poiseuille and Couette as well as Taylor- Couette swirling flows. The governing equations of momentum and energy are transformed into coupled and nonlinear ordinary differential equations using similarity transformation and then solved numerically. We critically evaluate the effect of dimensionless pressure gradients on fluid velocity and observed that the velocity increases as the dimensionless pressure gradient increases. Couette flows are simulated in different scenarios, including top plate moving, bottom plate moving, and top plate moving in adverse pressure gradient conditions. In a third scenario, the flow velocity profile revealed a backflow regime (BFR). A simple schematic model is, therefore, proposed to explain the presence of BFR in the flow's profile. Numerical and analytical solutions around the circular cylinder are presented. The marginal discrepancy between the analytical and numerical profiles is maximum at ~ 900 and 270° degrees, which indicates that the chosen method is suitable and capable of reproducing engineering problems. Velocity magnitude and vector diagrams show that the cylinder shape was found to have a significant effect on the flow field. The velocity at the top and bottom of the cylinder is twice the velocity that seen away from the cylinder. [ABSTRACT FROM AUTHOR]

The paper presents a multifunctional inverter for a three-phase single-stage gridconnected Solar Photo-Voltaic System (SPV) system with Enhanced Phase Locked Loop (EPLL)-based control algorithm. The EPLL-based Quadrature Signal Generation (QSG) estimates the magnitude of source voltage and load current signal and Phase-Locked Loop (PLL) estimates phase angle of the grid voltage. This estimation is used to design a proper controlled algorithm which improves the power quality such as reactive power compensation, harmonic rejection and DC offset rejection, in addition to feeding the SPV energy to load and grid. Perturb and Observe (P&O)-based Maximum Power Point Tracking (MPPT) is used to estimate the reference PV voltage signal and power. The EPLL-based controller tracks the signal even under distorted grid supply conditions such as voltage sag/swell and harmonics to improve the dynamic response. These multifunctional capabilities of the inverter make the system more efficient for feeding the SPV energy to grid. Various operating conditions are shown to validate the proposed controlled algorithm using MATLAB/Simulink. [ABSTRACT FROM AUTHOR]

Forests in developing countries are under tremendous pressure because of increasing dependence of human communities on timber, fodder, non-timber forest products, and fuelwood. Nepal's forests approximately cover 40% of its total geographical area, which experiences very high human dependence. In the present study, we propose an innovative approach of coupling socio-ecological attributes in Kayarkhola watershed in Churia hills of Nepal using remote sensing datasets and field observations to understand the patterns of fuelwood dynamics. Using multi-temporal moderate resolution satellite datasets, we have analyzed the patterns of land use and land cover change from 1990 to 2010 and assessed the effectiveness of community forestry management. The socio-ecological coupling provided quantification of most significant drivers of fuelwood dynamics. We observed low forest loss in community forests in comparison with those falling outside community forests. We conclude that family size, income levels, and percentage of illiterate persons are the most significant individual factors, whereas these factors along with the availability of agricultural land, supply of alternative energy sources are significantly inversely related drivers controlling the fuelwood dynamics. The scenarios developed in this study can be extrapolated in different landscapes to quantify the fuelwood dynamics, which will help in better forest cover management and conservation. [ABSTRACT FROM AUTHOR]

ABSTRACT Snow governs interaction between atmospheric and land surface processes in high mountains, and is also source of fresh water. It is thus important to both climate scientists and local communities. However, our understanding of snow cover dynamics in terms of space and time is limited across the Hindu Kush Himalaya ( HKH) region, which is known to be a climatically sensitive region. We used MODIS snow cover area ( SCA) data (2003-2012), APHRODITE temperature data (2000-2007), and monthly long term in-situ river discharge data of the Gandaki (1968-2010), Koshi (1977-2010) and Manas (1987-2004) basins to analyse variations among four basins. We gained insights into short term SCA and temperature, long term discharge trends, and regional variability thereby. Strong correlations were observed among SCA, temperature and discharge thereby highlighting the strong nexus between them. Temporal and spatial snow cover variability across the basins is strongly coupled with the variability of two weather systems: Western Disturbances ( WD) and Indian Monsoon System ( IMS), and strongly influenced by topography. Manifestation of these variability in terms if downstream discharge can have repercussion to water based sectors: hydropower and agriculture, as low flow seasons is seen affected. This study adds to our knowledge of snow fall and melt dynamics in the HKH region, and intra-annual snow melt contributions to downstream discharges. The study is limited by short span of data and it is desirable to perform a similar study using data representing a much longer time span. [ABSTRACT FROM AUTHOR]

Information on the meeting "Globalizing Societal Application of Scientific Research and Observations From Remote Sensing: The Path Forward," which was held on June 23-25, 2015 in Tacoma, Washington is presented. Key topics being discussed include capacity building using Earth observing (EO) systems and data as well as issues on public health and air quality, disaster management, and water resources.

The Himalayan mountain forest ecosystem has been degrading since the British ruled the area in the 1850s. Local understanding of the patterns and processes of degradation is desperately required to devise management strategies to halt this degradation and provide long-term sustainability. This work comprises a satellite image based study in combination with national expert validation to generate sub-district level statistics for forest cover over theWestern Himalaya, Pakistan, which accounts for approximately 67% of the total forest cover of the country. The time series of forest cover maps (1990, 2000, 2010) reveal extensive deforestation in the area. Indeed, approximately 170,684 ha of forest has been lost, which amounts to 0.38% per year clear cut or severely degraded during the last 20 years. A significant increase in the rate of deforestation is observed in the second half of the study period, where much of the loss occurs at the western borders along with Afghanistan. The current study is the first systematic and comprehensive effort to map changes to forest cover in Northern Pakistan. Deforestation hotspots identified at the sub-district level provide important insight into deforestation patterns, which may facilitate the development of appropriate forest conservation and management strategies in the country. [ABSTRACT FROM AUTHOR]

High levels of water-induced erosion in the transboundary Himalayan river basins are contributing to substantial changes in basin hydrology and inundation. Basin-wide information on erosion dynamics is needed for conservation planning, but field-based studies are limited. This study used remote sensing (RS) data and a geographic information system (GIS) to estimate the spatial distribution of soil erosion across the entire Koshi basin, to identify changes between 1990 and 2010, and to develop a conservation priority map. The revised universal soil loss equation (RUSLE) was used in an ArcGIS environment with rainfall erosivity, soil erodibility, slope length and steepness, cover-management, and support practice factors as primary parameters. The estimated annual erosion from the basin was around 40 million tonnes (40 million tonnes in 1990 and 42 million tonnes in 2010). The results were within the range of reported levels derived from isolated plot measurements and model estimates. Erosion risk was divided into eight classes from very low to extremely high and mapped to show the spatial pattern of soil erosion risk in the basin in 1990 and 2010. The erosion risk class remained unchanged between 1990 and 2010 in close to 87% of the study area, but increased over 9.0% of the area and decreased over 3.8%, indicating an overall worsening of the situation. Areas with a high and increasing risk of erosion were identified as priority areas for conservation. The study provides the first assessment of erosion dynamics at the basin level and provides a basis for identifying conservation priorities across the Koshi basin. The model has a good potential for application in similar river basins in the Himalayan region. [ABSTRACT FROM AUTHOR]

Satellite imagery has proven extremely useful for repetitive timeline-based data collection, because it offers a synoptic view and enables fast processing of large quantities of data. The changes in tree crown number and land cover in a very remote watershed (area 1305 ha) in Nepal were analyzed using a QuickBird image from 2006 and an IKONOS image from 2011. A geographic object-based image analysis (GEOBIA) was carried out using the region-growing technique for tree crown detection, delineation, and change assessment, and a multiresolution technique was used for land cover mapping and change analysis. The coefficient of determination for tree crown detection and delineation was 0.97 for QuickBird and 0.99 for IKONOS, calculated using a line-intercept transect method with 10 randomly selected windows (1×1 ha). The number of tree crowns decreased from 47,121 in 2006 to 41,689 in 2011, a loss of approximately 90 trees per month on average; the area of needle-leaved forest was reduced by 140 ha (23%) over the same period. Analysis of widely available very-high-resolution satellite images using GEOBIA techniques offers a cost-effective method for detecting changes in tree crown number and land cover in remote mountain valleys; the results provide the information needed to support improved local-level planning and forest management in such areas. [ABSTRACT FROM AUTHOR]

The present study characterises the tree communities with respect to topographic and climatic variables and identifies the most important environmental correlate of species richness in the southern region of Western Ghats Biodiversity Hotspot, India. Digitally derived environmental variables in combination with tree species richness information were analysed using Canonical Correspondence Analysis (CCA) to characterise the communities. Multiple regression technique based on stepwise backward elimination was used to identify the most important environment correlate of species richness. Canonical correspondence analysis results in six major tree communities along the first and second axes. Rainfall is the dominant environmental gradient influencing vegetation patterns on the first CCA axis while elevation showed the highest correlation with the second CCA axis. Backward elimination regression technique yielded rainfall as the most important environmental correlate of species richness. Results were in agreement with the observations in the Neotropics that rainier areas maintain high species diversity. [ABSTRACT FROM AUTHOR]

A majority of the research on forest fragmentation is primarily focused on animal groups rather than on tree communities because of the complex structural and functional behavior of the latter. In this study, we show that forest fragmentation provokes surprisingly rapid and profound alterations in tropical tree community. We examine forest fragments in the tropical region using high-resolution satellite imagery taken between 1973 and 2004 in the Southern Western Ghats (India) in relation to landscape patterns and phytosociological datasets. We have distinguished fragmentation in six categories—interior, perforated, edge, transitional, patch, and undetermined—around each forested pixel. Furthermore, we have characterized each of the fragment class in the evergreen and semi-evergreen forest in terms of its species composition and richness, its species similarity and abundance, and its regeneration status. Different landscape metrics have been used to infer patterns of land-use changes. Contiguous patches of >1,000 ha covered 90% of evergreen forest in 1973 with less porosity and minimal plantation and anthropogenic pressures; whereas in 2004, the area had 67% forest coverage and a high level of porosity, possibly due to Ochlandra spread and increased plantations which resulted in the loss of such contiguous patches. Results highlight the importance of landscape metrics in monitoring land-cover change over time. Our main conclusion was to develop an approach, which combines information regarding land cover, degree of fragmentation, and phytosociological inputs, to conserve and prioritize tropical ecosystems. [ABSTRACT FROM AUTHOR]

Tropical forests, which play critical roles in global biogeochemical cycles, radiation budgets and biodiversity, have undergone rapid changes in land cover in the last few decades. This study examines the complex process of land cover change in the biodiversity hotspot of Western Ghats, India, specifically investigating the effects of conservation measures within the Indira Gandhi Wildlife Sanctuary. Current vegetation patterns were mapped using an IRS P6 LISS III image and this was used together with Landsat MSS data from 1973 to map land cover transitions. Two major and divergent trends were observed. A dominant degradational trend can be attributed to agricultural expansion and infrastructure development while a successional trend, resulting from protection of the area, showed the resilience of the system after prolonged disturbances. The sanctuary appears susceptible to continuing disturbances under the current management regime but at lower rates than in surrounding unprotected areas. The study demonstrates that remotely sensed land cover assessments can have important contributions to monitoring land management strategies, understanding processes underpinning land use changes and helping to inform future conservation strategies. [ABSTRACT FROM AUTHOR]

We have used data generated using remote sensing and geographical information systems to categorize habitats, and then determined the relationship between the habitat categorizations and species-distribution patterns. A biologically rich hotspot—Kalakad-Mundanthurai Tiger Reserve, located at Southern Western Ghats, India, was chosen for this study. In order to spatially delineate areas of high species richness/diversity and endemic habitat zones, we have identified evergreen habitats in conjunction with landscape metrics, species assemblage, micro-habitats like slope, topography, species endemism, and proportion of core and edge species. A total of 236 species and 2,920 individuals were recorded using systematic stratified plots of 0.1 ha covering 47 plots. Hierarchical cluster analysis was done using Ward’s method. Plot information was used to identify clusters based on species density. The analysis showed five species assemblages that are quite distinct from each other in terms of dominant species. The distribution of endemic and edge species, land cover heterogeneity, and continuity of patches in these clusters were evaluated to understand the degree of disturbance and intactness at landscape scale. Integration of species assemblages and topography brought out four major elevation-slope complexes. Information on species composition (robust field survey) with spectral (hybrid classification) properties has shown 72% overall accuracy and distinguished four evergreen sub-groups and other land cover classes. The developed approach assumes great importance in the assessment of biodiversity and prioritizing the areas of conservation. [ABSTRACT FROM AUTHOR]

Forest fire has profound impacts on atmospheric chemistry, biogeochemical cycling and ecosystem structure. This feedback interaction may be hastened in climate change scenarios. In view of this, the present day knowledge about the forest fire condition in India has been reviewed. Operational monitoring, geospatial modelling and climate change uncertainties are discussed. Indicators for forest fire assessment and the role of geoinformatics tools in developing those parameters are identified. The need for developing an adaptive management strategy from the existing experience is emphasized, and specific points are recommended sector-wise with short- and long-term visions. [ABSTRACT FROM AUTHOR]

Aglaia bourdillonii is a plant narrowly endemic to the southern portion of the Western Ghats (WG), in peninsular India. To understand its ecological and geographic distribution, we used ecological niche modeling (ENM) based on detailed distributional information recently gathered, in relation to detailed climatic data sets. The ENMs successfully reconstructed key features of the species' geographic distribution, focusing almost entirely on the southern WG. Much of the species' distributional potential is already under protection, but our analysis allows identification of key zones for additional protection, all of which are adjacent to existing protected areas. ENM provides a useful tool for understanding the natural history of such rare and endangered species. [ABSTRACT FROM AUTHOR]

This paper gives an account of day-night active forest fire monitoring conducted over the sub-tropical and moist temperate forests of the Uttaranchal State, India, during 2005 using the Defence Meteorological Satellite Program - Operational Line Scan system (DMSP-OLS) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data. The state experienced heavy fire episodes during May-June 2005 and daily datasets of DMSP-OLS (night-time) and selected cloud-free MODIS (daytime) datasets were used in mapping active fire locations. DMSP-OLS collects data in visible (0.5 to 0.9 µm) and thermal (10.5 to 12.5 µm) bands and detects dim sources of lighting on the earth's surface, including fires. The enhanced fire algorithm for active fire detection (version 4) was used in deriving fire products from MODIS datasets. Fire locations derived from DMSP-OLS and MODIS data were validated with limited ground data from forest department and media reports. Results of the study indicated that the state experienced heavy fire episodes, most of them occurring during night-time rather than daytime. Validation of satellite-derived fires with ground data showed a high degree of spatial correlation. [ABSTRACT FROM AUTHOR]

Hydrolysis of methyloleate was optimized using lipase from Chromobacterium viscosum immobilized on IRC-50. The optimization was studied by a statistical methodology using response surface methodology (RSM). The cumulative interactive effect of substrate, water concentration and time was studied in optimizing the hydrolysis of methyloleate. The interactive effect of substrate-time was found to be significant compared to substrate-water and time-water interactions. A well correlation was observed between the optimum values obtained from the response surface contour plots and from the quadratic regression model equation. The optimal values obtained for substrate, water and time were found to be in the experimental range chosen. [ABSTRACT FROM AUTHOR]

Various lipases were screened for their hydrolytic efficiency towards methyloleate. Lipase from Chromobacterium viscosum gave highest hydrolysis efficiency of 92% in 24 h. Different cation exchange resins were screened to immobilize lipase from Chromobacterium viscosum. A weakly acidic macroreticular type resin, IRC-50 having carboxyl end group functionality gave highest activity yield of 18.8%. Strongly acidic cation exchange resins with sulphonic functionality and macroreticular type did not give much activity yield when compared to weakly acidic non macroreticular type resins. It was observed that end group functionality and structure of the matrices plays an important role in obtaining highest activity yield. For a specific water concentration, the hydrolysis ratio reached 85% in less than 7 h when the substrate to enzyme ratio was 4. As the ratio is increased above 4, the availability of water at the interface has become a limitation for obtaining maximum hydrolysis. [ABSTRACT FROM AUTHOR]

Resilience is the capacity of an ecosystem to absorb disturbance and undergo change while maintaining its essential structure, functions, identity and feedbacks. The forests of the Hindu Kush Himalayan (HKH) region are vulnerable to both natural and anthropogenic changes, and the forest land conversion and degradation. Using satellite-derived tree canopy cover percent data and precipitation as the explaining variable, we studied the forest cover resilience in a geospatial framework employing the logistic regression and polynomial equation fitting. Out of the 4.3millionkm2 geographical areas, 873,650km2 (20.20%) was under the forest in 2000 and experienced loss of 11,250km2 during 2000-2010. We could model the forest cover and treeless areas fairly than the scrub and grassland owing to the variation in precipitation pattern. The majority of the forest cover (59.3%) has been estimated to have less resilience owing to the receipt of <1650 mm of total annual precipitation, whereas only 375km2 forest area could change to scrub that shows the least resilience. About 94.4% of treeless areas were estimated to be stable, while only 1% (25,200km2) area could accommodate the grassland. The resilient forest areas estimated and observed, owing to the mapping and modelling protocols used in this study, shall be useful in conservation planning in the HKH region. [ABSTRACT FROM AUTHOR]