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Sainath Aher Sambhaji Shinde Shantamoy Guha Mrinmoy Majumder 《Journal of Earth System Science》2017,126(2):21
An innovative approach for drought identification is developed using Multi-Criteria Decision Making (MCDM) and Artificial Neural Network (ANN) models from surveyed drought parameter data around the Dhalai river watershed in Tripura hinterlands, India. Total eight drought parameters, i.e., precipitation, soil moisture, evapotranspiration, vegetation canopy, cropping pattern, temperature, cultivated land, and groundwater level were obtained from expert, literature and cultivator survey. Then, the Analytic Hierarchy Process (AHP) and Analytic Network Process (ANP) were used for weighting of parameters and Drought Index Identification (DII). Field data of weighted parameters in the meso scale Dhalai River watershed were collected and used to train the ANN model. The developed ANN model was used in the same watershed for identification of drought. Results indicate that the Limited-Memory Quasi-Newton algorithm was better than the commonly used training method. Results obtained from the ANN model shows the drought index developed from the study area ranges from 0.32 to 0.72. Overall analysis revealed that, with appropriate training, the ANN model can be used in the areas where the model is calibrated, or other areas where the range of input parameters is similar to the calibrated region for drought identification. 相似文献
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K. Nageswara Rao N. Sadakata Vasant Shinde A. S. Rajawat Ajai 《Frontiers of Earth Science》2010,4(4):410-416
The present study is an attempt to estimate the rates of subsidence in the Holocene sediments of the Godavari delta along
the east coast of India. Two boreholes dug at Panangipalli village in the delta revealed Early Historic culture material such
as potsherds including Coarse Red ware, Red-Slipped ware, Coarse Grey ware, and Black and Red ware, between 3.5 m and 9.0
m below the surface level. This suggests that the location was a human settlement of Andhra Satavahana period which flourished in the region between 3rd century BC and 3rd century AD. The fossil shells of Anadara sp. recovered from the borehole further downward at 11.5 m below the surface are considered to represent the intertidal swampy/lagoonal
environment. The age of the shells was determined through AMS 14C dating as 6400 cal a BP. The presence of about 2.5m thick intertidal swampy/lagoonal material between 9.0 m and 11.5 m depth,
suggests post-depositional subsidence at an average rate of less than 1.0 mm·a−1. However, a higher rate of subsidence of about 2.0 mm to 4.0 mm·a−1 is estimated for the upper 9.0 m thick floodplain sediment unit which embeds the Early Historic culture remains. The increased
rates of subsidence during the last two millennia when compared to the earlier period in this part of the Godavari delta could
be due to anthropogenic activity of deforestation and agriculture leading to accelerated soil erosion in the catchment and
increased sedimentation in the delta. 相似文献
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Kiran A. Shinde 《Geoforum》2012,43(1):116-127
Many Hindu pilgrimage sites in India experience heavy influxes of pilgrims and are subject to considerable environmental impact. Existing literature on the study of the environment in pilgrimage sites, however, appears to follow two divergent directions: one emphasizes degradation of the physical environment while the other highlights the sacred character of the place and how that is compromised by contemporary visitor flows. The aim of this paper is to move beyond this divergence and to demonstrate how contemporary environmental problems are outcomes related to a historical process of environmental change that accompanies the making of a sacred place. This paper is based on a case study of Vrindavan, a Hindu pilgrimage site associated with Krishna worship in northern India. More than 6 million visitors visit Vrindavan annually. Using a historical geography approach and socio-spatial dialectic conceptual framework, the paper explains how this pilgrimage landscape was established in the 15th century, and how since then it has evolved into a religious-urban place comprising more than 5500 temples. Its development is categorized into three periods: pre-colonial, colonial and post-colonial. In each period, the socio-spatial fabric showed significant transformations that resulted from the interaction of three critical factors: the influence of local and global socio-economic processes on the cultural economy of pilgrimage, the relationship of this economy to spatial change, and institutional controls that regulated the other two factors. It is argued that the environment of pilgrimage is simultaneously social, economic, cultural and religious and shaped by the need to maintain the place as sacred. This insight is useful for a better understanding of contemporary environmental problems so that they may be addressed effectively. 相似文献
6.
Jyoti Shah Deepak C. Srivastava Vipul Rastogi Rajit Ghosh Aditi Pal 《Journal of the Geological Society of India》2010,75(1):89-97
Most of the existing methods of strain analysis can estimate strain in a single form of distorted brachiopod, or trilobite
provided independent evidence, such as the association of the fossil with cleavage and/or stretching lineation is available
for inferring the direction of maximum principal strain. This article proposes a simple computer graphics based method and
its MATLAB code that determine the minimum amount of strain in a single distorted fossil form even if data for inferring the
maximum principal strain direction are lacking. Our method is a rapid computer-graphics alternative to some of the existing
analytical methods.
In a distorted fossil form of original bilateral symmetry, the relative senses of angular shears along the hinge line and
the median line are mutually opposite to each other. It follows, therefore, that the maximum principal strain direction lies
within the acute angle between the hinge and the median lines in the plane of the fossil. Using this principle, our method
performs several simulations such that each simulation retrodeforms the distorted fossil by assuming a particular orientation,
lying within the acute angle between the hinge line and the median line, as the potential direction of the maximum principal
strain. Each simulation of retrodeformation yields a potential strain ratio. The distribution of all the potential strain
ratios, obtained by assuming different orientations as the potential directions of the maximum strain, is typically a parabola-like
curve with a distinct vertex that corresponds to the minimum amount of strain in the distorted fossil. An entirely computer
graphical approach is somewhat time-intensive because it involves a large number of retrodeformational simulations. We, therefore,
give a MATLAB code, namely, the Minstrain, that rapidly retrodeforms the fossil and determines the minimum strain with precision. 相似文献
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Quantitative Determination of Soil Erosion and Prioritization of Micro-Watersheds Using Remote Sensing and GIS 总被引：5，自引：0，他引：5
Vipul Shinde Arabinda Sharma Kamlesh N. Tiwari Manjushree Singh 《Journal of the Indian Society of Remote Sensing》2011,39(2):181-192
Soil erosion which occurs at spatially varying rate is a widespread threat to sustainable resource management at watershed scale. Thus estimation of soil loss and identification of critical area for implementation of best management practice is central to success of soil conservation programme. The present study focuses application of most widely used Universal Soil Loss Equation (USLE) to determine soil erosion and prioritization of micro-watersheds of Upper Damodar Valley Catchment (UDVC) of India. Annual average soil loss for the entire basin is 23.17 t/ha/yr; for micro-watersheds. High soil loss is observed in 345 micro-watersheds, medium in 159 micro-watersheds and low soil loss is observed in 201 micro-watersheds. It is found that, out of 705 micro-watersheds of UDVC, 453 micro-watersheds are in agreement with AISLUS suggested priority which is based on observed sediment yield, 116 micro-watersheds under predict and 136 micro-watersheds over predict the priority. Geographic Information System (GIS) is applied to prepare various layers of USLE parameters which interactively estimate soil erosion at micro-watershed level. The main advantage of the GIS methodology is in providing quick information on the estimated value of soil loss for any part of the investigated area. 相似文献
8.
ICME Identification from Solar Wind Ion Measurements 总被引：1，自引：0，他引：1
Interplanetary coronal mass ejections (ICMEs), the interplanetary counterpart of coronal mass ejections (CMEs), are most commonly
identified by their enhanced magnetic field strengths and rotating magnetic field orientation. However, there are other frequent
signatures in the plasma. We use a pair of these signatures, a linearly decreasing plasma bulk velocity and a cool (< 20 km s−1) ion thermal speed, to identify candidate ICMEs. Many ICMEs, identified through their magnetic signatures, are also found
by their ion signatures alone. However, many are not. These missed ICMEs appear not to be expanding, even when they are accompanied
by leading shocks. The ICMEs with both the magnetic and ion signatures appear to be expanding as judged from either set of
observations. The most clearly defined ICMEs have transit times from the Sun and growth times to the observed size that are
equal. These ropes fit the paradigm of compact magnetic structures arising low in the corona and expanding uniformly in time,
as they travel at constant center of mass speed toward 1 AU. 相似文献
9.
Several experiments are carried out to understand the deformation behavior of reinforced soil retaining wall with limited
fill zones under vertical surcharge strip loading. Test set-up along with all the instrumentations is developed to carry out
the experiments. Panel displacements and strain distribution along geogrid layers are observed. Effectiveness of the reinforced
soil wall is also evaluated using a geogrid material. Finite element analysis is carried out using commercial software PLAXIS
version 8 for the above problem without and with anchoring of reinforced soil retaining wall in the limited fill zone. The
results are compared and reported in this present paper. 相似文献
10.
Because the majority of spacecraft that observe Interplanetary Coronal Mass Ejections (ICMEs) reside in the neighborhood of
the Earth while the best coronagraph observations of Coronal Mass Ejections (CMEs) are of eruptions orthogonal to the Earth–Sun
line, the observation of a causative CME on the Sun is not a prerequisite for defining an ICME seen in space. Several observers
have compiled lists of ICMEs for the ascending and maximum phase of solar cycle 23 based on varying criteria but derived from
a common database: WIND and ACE solar wind and IMF measurements. The criteria include a stronger than ambient magnetic field,
rotating magnetic field, low beta, low ion temperature, declining velocity profile, and other characteristics. When we examine
the events on these lists we find that these various lists differ considerably. Of the 240 events identified on one or more
lists only 22 are consensus identifications. Even when the groups do agree on the identification of an event, they do not
agree on when the event starts and stops. Sometimes these differences are of only a few hours but at times they can be up
to a day difference. Herein we illustrate the disparity in ICME lists and propose a scheme for rating ICMEs according to the
behavior of their fluid parameters in comparison with the flux rope paradigm. 相似文献