Modeling potential forest fire danger using modis data     

K. V. S. Badarinath  K. Madhavilatha  T. R. Kiran Chand  M. S. R. Murthy 《Journal of the Indian Society of Remote Sensing》2004,32(4):343-350

Generation of fire danger maps play a vital role in forest fire management like forest fire research, locating lookout towers, risk assessment and for various other simulation studies. The present study addresses remote sensing and GIS applications in generating fire danger maps for tropical deciduous forests. Fire danger variables such as fuel type, topography, temperature, and relative humidity have been used in modeling fire danger. Information on local climate patterns and past fire records has been used to derive fire frequency map of the study area. Intermediate indices were derived using multiple regressions, where fire frequency data is taken as dependent variable. Results indicate that forests near human settlements are more vulnerable to forest fires.  相似文献   

Estimation of surface heat flux and inversion height with a Doppler acoustic sounder     

L. K. Sadani  B. S. Murthy 《Journal of Earth System Science》1996,105(3):289-307

In this paper, acoustic sounder (sodar) derived vertical velocity variance (σ _w ² ) and inversion height (Z _i) are used to compute the surface heat flux during the convective activity in the morning hours. The surface heat flux computed by these methods is found to be of the same order of magnitude as that obtained from tower measurements. Inversion heights derived from sodar reflectivity profiles averaged for an hour are compared with those obtained from the σ _w ² /Z profile. Variation of σ _w ² in the mixed layer is discussed. The data were collected during the Monsoon Trough Boundary Layer Experiment 1990 at Kharagpur. The analysis is made for four days which represent the pre-monsoon, onset, active and relatively weak phases of the summer monsoon 1990. The interaction of the ABL with the monsoon activity is studied in terms of the variation of inversion height, vertical velocity variance and surface heat flux as monsoon progresses from June to August.  相似文献   

Magnetic studies on the remanence carriers in igneous rocks of different ages     

C Radhakrishnamurty  S D Likhite  G S Murthy 《Journal of Earth System Science》1988,97(1):81-85

A critical study on the type of the magnetic grains, both in composition and domain state, in rocks of different ages has been carried out. One simple, fast and non-destructive test, which can provide useful information on the nature of the magnetic grains in freshly collected samples, seems to be the ratio of susceptibilities at 77 and 300 K. This ratio, termed relative susceptibility, ranges from 0·1, for samples containing 70% ulvospinel bearing titanomagnetite (TM70) to 1·50 for cation deficient magnetite bearing ones. The results indicate that the value of 0·1 for TM70 is not greatly affected even if some amount of TM80, which is nonmagnetic at 300 K, is present in a rock sample. However, the coercive force at 77 K will increase considerably for such a sample. The effects of mixed compositions and domain states of magnetic grains on the overall behaviour of basalts are discussed.  相似文献   

Inversion of gravity and magnetic anomalies over some bodies of simple geometric shape   总被引：1，自引：0，他引：1  

Atchuta Rao  D.  Ram Babu  H. V.  Venkata Raju  D. Ch. 《Pure and Applied Geophysics》1985,123(2):239-249

The general expression for gravity and magnetic anomalies over thin sheets and sloping contacts may be expressed as a polynomial of the formFx ²+C₁Fx+C₂F+C₃x³+C₄x²+C₅x+C₆. The initial parameters of the source are obtained from the coefficientsC ₁, C₂,..., C₆ which may be solved by inverting a 6×6 matrix. The initial parameters are modified by successive iteration process using the difference formula until the root mean square error between the observed and calculated anomalies is a minimum. The regional background which may be in the form of a polynomial is estimated by the computer itself. This method is applied on a number of field anomalies and is found to yield reliable estimates of depth and other parameters of the source.  相似文献   

Productivity optimisation in weak sedimentary formations for improved coal production and roof stability—an approach     

V. M. S. R. Murthy  Santosh Kumar Ray 《Geotechnical and Geological Engineering》2002,20(3):273-290

Far-field peak particle velocity (PPV) measurements were made in the roof while blasting in coal development drivages at Tandsi Mine, Western Coalfields Limited, India. The roof was fragile at this mine and was posing constant support problems for mining, resulting in low productivity. The PPV measurements have been used to decipher the damage zone in the roof. The extent of damage obtained has been compared to establish the threshold limits for the damage zone. Conversely, the maximum charge per delay that can be exploded is calculated and a suitable blast design has been recommended for maintaining the roof stability and pull. A roof vibration predictor equation has been developed that shows a consistent trend indicating that it may have future use in a similar geo-mining setup. The blast pattern recommended has reduced the damage extent, though marginally, but helped in improving pull. Critical PPV for incipient rock damage in underground coal mine development drivages under fragile roof were computed. The PPV level for incipient crack growth was found to vary from 500 to 800 mm/s while for overbreak it varied from 800 to 1200 mm/s. It was also observed that the location of cut holes, charge concentration and firing sequence were found to be responsible for the difference in their damage potential.  相似文献   

Estimation of number of deaths associated with exposure to excess ambient PM10 air pollution     

D. Giri M.Sc.  V. K. Murthy M.Sc. Ph.D.  P. R. Adhikary M.Sc. Ph.D.  S. N. Khanal M.Sc. Ph.D. 《International Journal of Environmental Science and Technology》2007,4(2):183-188

The respirable particle matter (PM₁₀) concentration in urban areas has been a chronic cause concern and principal reason for increased morbidity rate among resident population. The present study aimed at estimating a discrete event like mortality rate associated and attributable to excess particulate matter pollution in the Kathmandu Valley area. The Government of Nepal conducts air monitoring of particulates at its air monitoring site network covering valley area. Adopting the data available with respect to PM₁₀ and with several other considerations like cutoff value for PM₁₀, mean annual concentration, demographic data of valley, exceedance to the reference cutoff value, attributable fraction evolution and computation relative risk attributable to PM₁₀ was computed. Assumption was made about the relative risk of long-term average PM₁₀ exposure on natural mortality estimated and reported from a previous study. The estimation or mortality rate in our case was 0.95% after all these considerations and computation. This implies that 95 deaths out of 10,000 deaths are due to particulate pollution existing in the Kathmandu Valley Area.  相似文献   

Ambient air quality of Kathmandu valley as reflected by atmospheric particulate matter concentrations (PM10)     

D. Giri  K. V. Murthy  P. R. Adhikary  S. N. Khanal 《International Journal of Environmental Science and Technology》2006,3(4):403-410

This paper presents the analysis and interpretation of ambient particulate matter concentrations measured as PM₁₀ at a network of six air monitoring stations in Kathmandu valley during the years, 2003 through 2005. The purpose was to understand the pollution trends associated with different areas considering levels particulate matter concentrations representing the ambient air quality of Kathmandu valley. The study indicate that particulate concentrations (PM₁₀) measured are persistently higher at air sampling sites representing roadside areas compared to the background sites. The inter-station network variability with respect the particulate pollution suggests optimizing resources. The comparison of annual average PM₁₀ concentration observed at six air-monitoring sites in Kathmandu Valley with standard annual average concentration prescribed by World Health Organization as well as Europe Union indicates serious PM₁₀ pollution in Kathmandu valley.  相似文献   

Einstein–Rosen Universe in a Scalar-Tensor Theory of Gravitation     

D. R. K. Reddy  CH. C. S. V. V. R. Murthy  R. Venkateswarlu 《Astrophysics and Space Science》2006,301(1-4):79-82

Field equations in the presence of a perfect fluid distribution are obtained in a scalar-tensor theory of gravitation proposed by Saez and Ballester (Phys. Lett. 113, 1985, 467) with the aid of Einstein–Rosen cylindrically symmetric metric. A static vacuum model and a non-static stiff fluid model are presented. The physical and geometrical properties of the stiff fluid model are studied.  相似文献   

Loktak notified Wetland ecosystem and its catchment     

N Randhir Singh  N S Singh  J K Garg  T V R Murthy 《Journal of the Indian Society of Remote Sensing》2000,28(2-3):159-169

Conservation of wetland is considered paramount in view of its ecological significance. The availability of reliable and up-to-date data on seasonal water spread, tropic state of wetland and bio-physical parameters besides the landuse/cover of the catchment area is a prerequisite for ‘wise use’ of any wetland ecosystem. The present study is carried out to identify the above parameters of Loktak notified wetland through visual interpretation of 1RS IA/IB LISS II FCC of 1990 and 1994/95. It indicates that the water spread of the lake is showing a declining trend and an increasing trend for aquatic vegetation. In 1990 post-monsoon data water spread was 15441 ha which become 11166 ha in October 1994. The extent of water spread further decreases by pre-monsoon season and was found to be 7875 ha in the IRS LISS II data of March 1995. Like-wise area under aquatic vegetation and associated marshy/ swamps was 10499 ha in October 1990 and 13506 ha in October 1994. Catchment of Loktak lake (104872 ha) is highly degraded and forest covers only 7205 ha area. Agriculture is the main land use (35576 ha) in the catchment and substantial area is also under land with or without scrub. Thus, there is a need to rehabilitate the catchment by way of planting trees for reducing silt load in the Loktak lake and ensuring its ‘wise use’.  相似文献   

Abe Barek landslide and landslide susceptibility assessment in Badakhshan Province,Afghanistan   总被引：2，自引：0，他引：2  

Jianqiang Zhang  Deo Raj Gurung  Rongkun Liu  Manchiraju Sri Ramachandra Murthy  Fenghuan Su 《Landslides》2015,12(3):597-609

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