Empirical estimation of default and asset correlation of large corporates and banks in India

Estimation of default and asset correlation is crucial for banks to manage and measure portfolio credit risk. This would require studying the risk profile of the banks’ entire credit portfolio and developing the appropriate methodology for the estimation of default dependence. Measurement and management of correlation risk in the credit portfolio of banks has also become an important area of concern for bank regulators worldwide. The BCBS (2006) has specifically included an asset correlation factor in the computation of credit risk capital requirement by banks adopting the Internal Ratings Based Approach. We estimate default correlation in the credit portfolio of banks. These correlation estimates will help the regulator in India to understand the linkage between bank’s portfolio default risks with the systematic factors. We also derive default and asset correlations of Indian corporate and compare it with global scenario. The work tries to find the relationship of the correlation to the default probability as specified by the Basel committee. The findings of this paper could be used further in estimating portfolio credit risk, economic capital and risk adjusted returns on economic capital for large corporate exposures of banks.Default Correlation, Asset Correlation, Credit Portfolio Risk

Empirical estimation of default and asset correlation of large corporates and banks in India

Estimation of default and asset correlation is crucial for banks to manage and measure portfolio credit risk. This would require studying the risk profile of the banks’ entire credit portfolio and developing the appropriate methodology for the estimation of default dependence. Measurement and management of correlation risk in the credit portfolio of banks has also become an important area of concern for bank regulators worldwide. The BCBS (2006) has specifically included an asset correlation factor in the computation of credit risk capital requirement by banks adopting the Internal Ratings Based Approach. We estimate default correlation in the credit portfolio of banks. These correlation estimates will help the regulator in India to understand the linkage between bank’s portfolio default risks with the systematic factors. We also derive default and asset correlations of Indian corporate and compare it with global scenario. The work tries to find the relationship of the correlation to the default probability as specified by the Basel committee. The findings of this paper could be used further in estimating portfolio credit risk, economic capital and risk adjusted returns on economic capital for large corporate exposures of banks

Vegetation response to extreme climate events on the Mongolian Plateau from 2000 to 2010

Climate change has led to more frequent extreme winters (aka, dzud) and summer droughts on the Mongolian Plateau during the last decade. Among these events, the 2000–2002 combined summer drought–dzud and 2010 dzud were the most severe on vegetation. We examined the vegetation response to these extremes through the past decade across the Mongolian Plateau as compared to decadal means. We first assessed the severity and extent of drought using the Tropical Rainfall Measuring Mission (TRMM) precipitation data and the Palmer drought severity index (PDSI). We then examined the effects of drought by mapping anomalies in vegetation indices (EVI, EVI2) and land surface temperature derived from MODIS and AVHRR for the period of 2000–2010. We found that the standardized anomalies of vegetation indices exhibited positively skewed frequency distributions in dry years, which were more common for the desert biome than for grasslands. For the desert biome, the dry years (2000–2001, 2005 and 2009) were characterized by negative anomalies with peak values between �1.5 and �0.5 and were statistically different (P \u3c 0:001) from relatively wet years (2003, 2004 and 2007). Conversely, the frequency distributions of the dry years were not statistically different (p \u3c 0:001) from those of the relatively wet years for the grassland biome, showing that they were less responsive to drought and more resilient than the desert biome. We found that the desert biome is more vulnerable to drought than the grassland biome. Spatially averaged EVI was strongly correlated with the proportion of land area affected by drought (PDSI \u3c �1) in Inner Mongolia (IM) and Outer Mongolia (OM), showing that droughts substantially reduced vegetation activity. The correlation was stronger for the desert biome (R2 D 65 and 60, p \u3c 0:05) than for the IM grassland biome (R2 D 53, p \u3c 0:05). Our results showed significant differences in the responses to extreme climatic events (summer drought and dzud) between the desert and grassland biomes on the Plateau

Surface Engineering for Phase Change Heat Transfer: A Review

Among numerous challenges to meet the rising global energy demand in a sustainable manner, improving phase change heat transfer has been at the forefront of engineering research for decades. The high heat transfer rates associated with phase change heat transfer are essential to energy and industry applications; but phase change is also inherently associated with poor thermodynamic efficiencies at low heat flux, and violent instabilities at high heat flux. Engineers have tried since the 1930's to fabricate solid surfaces that improve phase change heat transfer. The development of micro and nanotechnologies has made feasible the high-resolution control of surface texture and chemistry over length scales ranging from molecular levels to centimeters. This paper reviews the fabrication techniques available for metallic and silicon-based surfaces, considering sintered and polymeric coatings. The influence of such surfaces in multiphase processes of high practical interest, e.g., boiling, condensation, freezing, and the associated physical phenomena are reviewed. The case is made that while engineers are in principle able to manufacture surfaces with optimum nucleation or thermofluid transport characteristics, more theoretical and experimental efforts are needed to guide the design and cost-effective fabrication of surfaces that not only satisfy the existing technological needs, but also catalyze new discoveries

Interpretation of Variations in Modis-Measured Greenness Levels of Amazon Forests During 2000 to 2009

This work investigates variations in satellite-measured greenness of Amazon forests using ten years of NASA Moderate Resolution Imaging Spectroradiometer (MODIS) enhanced vegetation index (EVI) data. Corruption of optical remote sensing data with clouds and aerosols is prevalent in this region; filtering corrupted data causes spatial sampling constraints, as well as reducing the record length, which introduces large biases in estimates of greenness anomalies. The EVI data, analyzed in multiple ways and taking into account EVI accuracy, consistently show a pattern of negligible changes in the greenness levels of forests both in the area affected by drought in 2005 and outside it. Small random patches of anomalous greening and browning-especially prominent in 2009-appear in all ten years, irrespective of contemporaneous variations in precipitation, but with no persistence over time. The fact that over 90% of the EVI anomalies are insignificantly small-within the envelope of error (95% confidence interval) in EVI-warrants cautious interpretation of these results: there were no changes in the greenness of these forests, or if there were changes, the EVI data failed to capture these either because the constituent reflectances were saturated or the moderate resolution precluded viewing small-scale variations. This suggests a need for more accurate and spatially resolved synoptic views from satellite data and corroborating comprehensive ground sampling to understand the greenness dynamics of these forests

Probiotic-based cultivation of Clarias batrachus : importance and future perspective

Clarias batrachus (Linn.) is widely recognized in Indian sub-continent for its nutritional and economic significance. At present, it remains at a merely vulnerable state. Pathogenic infections, diminution of natural habitats and introduction of allied exotic fishes are the causes of productivity constraint, particularly in Southern Asia. Conversely, African cat fish Clarias gariepinus has been significantly identified as a potential threat to biodiversity, despite being its large scale cultivation across the world. Thus emphasis on indigenous C. batrachus farming is becoming inevitable. Currently, screening of autochthonous probiotic organisms for the cultivation of C. batrachus in semi-intensive manner is getting importance. At the same time, molecular omics-based technologies are also gaining considerable attention to identify potential probiotic markers. This review provides an overall concept of probiotics, its application and future perspectives in relation to the cultivation of C. batrachus

Characterizing Morphology and Nonlinear Elastic Properties of Normal and Thermally Stressed Engineered Oral Mucosal Tissues Using Scanning Acoustic Microscopy

This study examines the use of high-resolution ultrasound to monitor changes in the morphology and nonlinear elastic properties of engineered oral mucosal tissues under normal and thermally stressed culture conditions. Nonlinear elastic properties were determined by first developing strain maps from acoustic ultrasound, followed by fitting of nonlinear stress?strain data to a 1-term Ogden model. Testing examined a clinically developed ex vivo produced oral mucosa equivalent (EVPOME). As seeded cells proliferate on an EVPOME surface, they produce a keratinized protective upper layer that fills in and smoothens out surface irregularities. These transformations can also alter the nonlinear stress/strain parameters as EVPOME cells differentiate. This EVPOME behavior is similar to those of natural oral mucosal tissues and in contrast to an unseeded scaffold. If ultrasonic monitoring could be developed, then tissue cultivation could be adjusted in-process to account for biological variations in their development of the stratified cellular layer. In addition to ultrasonic testing, an in-house-built compression system capable of accurate measurements on small (?1.0?1.5?cm2) tissue samples is presented. Results showed a near 2.5-fold difference in the stiffness properties between the unstressed EVPOME and the noncell-seeded acellular scaffold (AlloDerm?). There were also 4?greater differences in root mean square values of the thickness in the unseeded AlloDerm compared to the mature unstressed EVPOME; this is a strong indicator for quantifying surface roughness.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140241/1/ten.tec.2012.0467.pd

Surface engineering for phase change heat transfer: A review

Owing to advances in micro- and nanofabrication methods over the last two decades, the degree of sophistication with which solid surfaces can be engineered today has caused a resurgence of interest in the topic of engineering surfaces for phase change heat transfer. This review aims at bridging the gap between the material sciences and heat transfer communities. It makes the argument that optimum surfaces need to address the specificities of phase change heat transfer in the way that a key matches its lock. This calls for the design and fabrication of adaptive surfaces with multiscale textures and non-uniform wettability. Among numerous challenges to meet the rising global energy demand in a sustainable manner, improving phase change heat transfer has been at the forefront of engineering research for decades. The high heat transfer rates associated with phase change heat transfer are essential to energy and industry applications; but phase change is also inherently associated with poor thermodynamic efficiency at low heat flux, and violent instabilities at high heat flux. Engineers have tried since the 1930s to fabricate solid surfaces that improve phase change heat transfer. The development of micro and nanotechnologies has made feasible the high-resolution control of surface texture and chemistry over length scales ranging from molecular levels to centimeters. This paper reviews the fabrication techniques available for metallic and silicon-based surfaces, considering sintered and polymeric coatings. The influence of such surfaces in multiphase processes of high practical interest, e.g., boiling, condensation, freezing, and the associated physical phenomena are reviewed. The case is made that while engineers are in principle able to manufacture surfaces with optimum nucleation or thermofluid transport characteristics, more theoretical and experimental efforts are needed to guide the design and cost-effective fabrication of surfaces that not only satisfy the existing technological needs, but also catalyze new discoverie

Diversity and distribution of wild mushrooms in different forest areas of Bankura district, WB, India

Mushrooms are macroscopic fruit bodies of fungi; one of the most diverse groups of living organisms distributed all over the world. In recent past, they have gained significant scientific attention for their profound nutraceutical potentiality. The objective of the present study was to explore the diversity and ecological distribution of mushrooms in different forest areas of Bankura district. The study area includes intermittent dense forest and flood plains from middle-east to eastern part of Bankura district. However, this area received very little attention from a conservation perspective, and there is no such documentation on mushrooms of this area. The survey was conducted from August 2019 to October 2020 including vivid field surveys in the forest depots. The study has revealed a total of 53 identified mushroom species belonging to 40 genera and 30 families. The study has also identified 25 edible, 18 inedible and 15 medicinally potential mushrooms. The genus Russula and the family Russulaceae dominates the myco-population. The finding shows that this region is rich in macrofungal diversity complicatedly linked to the functioning of the local ecosystem. The present study opens new possibilities regarding the exploration and utilization of wild mushrooms in India