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181.
B. R. Parida B. Oinam N. R. Patel N. Sharma R. Kandwal M. K. Hazarika 《International journal of remote sensing》2013,34(14):4219-4235
The Moderate Resolution Imaging Spectroradiometer (MODIS) has provided an improved capability for moderate resolution land surface monitoring and for studying surface temperature variations. Surface temperature is a key variable in the surface energy balance. To investigate the temporal variation of surface temperature in relation to different vegetation types, MODIS data from 2000–04 were used, especially in the reproductive phase of crops (September–October). The vegetation types used for this study were agriculture in desert areas, rainfed agriculture, irrigated agriculture, and forest. We found that among the different vegetation types, the desert‐based agriculture showed the highest surface temperature followed by rainfed agriculture, irrigated agriculture, and forest. The variation in surface temperature indicates that the climatic variation is mostly determined by the different types of vegetation cover on the Earth's surface rather than rapid climate change attributable to climatic sources. The mean land surface temperature (LST) and air temperature (T a) were plotted for each vegetation type from September to October during 2000 and 2004. Higher temperatures were observed for each vegetation type in 2000 as compared to 2004 and lower total rainfall was observed in 2000. The relationship between MODIS LST and T a measurements from meteorological stations was established and illustrated that years 2000 and 2004 had a distinct climatic variability within the time‐frame in the study area. In all test sites, the study found that there was a high correlation (r = 0.80–0.98) between LST and T a. 相似文献
182.
Chaitali Sarkar Alaka Gadgil Kanishka Mallick N. K. Patel J. S. Parihar 《International journal of remote sensing》2013,34(11):3271-3293
Clear‐sky dekadal relative evapotranspiration (RET) was derived using the surface energy‐balance approach applied to 10‐day composite NOAA PAL (8 km×8 km) datasets over the Indian landmass. This was further used to differentiate between growth characteristics for an irrigated intensive agriculture over a northern India state (e.g. Punjab) and a rainfed ill‐posed agriculture over a central India state (e.g. Madhya Pradesh) using time‐series data sets for five growing years (June–April): 1996–1997, 1997–1998, 1998–1999, 1999–2000, and 2000–2001. The triangular scatter between RET and normalized difference vegetation index (NDVI) showed that the minimum RET increases linearly with NDVI producing a ‘basal line’ that represents relative canopy transpiration only. A clear distinction in scatter was found between the two contrasting agro‐ecosystems showing a higher RET or root zone wetness in irrigated than rainfed systems. In rainfed rice‐growing regions, an inverse correlation (0.6–0.75) was found between RET and the Keetch–Byram meteorological drought index (KBDI), and a substantial reduction in RET was also found in a sub‐normal (2000) compared with a normal (1999) monsoon season. RET estimates were found to be most sensitive to atmospheric transmissivity followed by other land‐surface radiation budget inputs, such as NDVI, LST, and albedo. Error propagation due to three surface parameters is the opposite of that for transmissivity. The maximum possible error in clear‐sky NOAA PAL RET was estimated to be 12–15%. This test study would be helpful in deriving RET using optical and thermal data from a suite of current and future Indian geostationary satellite sensors for monitoring growing conditions. 相似文献
183.
Heald R. Aingaran K. Amir C. Ang M. Boland M. Dixit P. Gouldsberry G. Greenley D. Grinberg J. Hart J. Horel T. Wen-Jay Hsu Kaku J. Chin Kim Song Kim Klass F. Kwan H. Lauterbach G. Lo R. McIntyre H. Mehta A. Murata D. Nguyen S. Yet-Ping Pai Patel S. Shin K. Tam K. Vishwanthaiah S. Wu J. Yee G. You E. 《Solid-State Circuits, IEEE Journal of》2000,35(11):1526-1538
This quad-issue processor achieves 1-GHz operation through improved dynamic circuit techniques in critical paths and a more extensive on-chip memory system which scales in both bandwidth and latency. Critical logic paths use domino, delayed clocked domino, and logic embedded in dynamic flip-flops for minimum delay. A 64-KB sum-addressed memory data cache combines the address offset add with the cache decode, allowing the average memory latency to scale by more than the clock ratio. Memory bandwidth is improved by using wave pipelined SRAM designs for on-chip caches and a write cache for store traffic. Memory power is controlled without increased latency by use of delayed-reset logic decoders. The chip operates at 1000 MHz and dissipates less than 80 W from a 1.6-V supply. It contains 23 million transistors (12 million in RAM cells) on a 244 mm2 die 相似文献
184.
N,N-bis (2-hydroxyethyl) fatty amide (HAFA) derived from dehydrated castor oil (DCO) has been employed as a curing agent for
a carboxylic acid functional acrylic resin (AAR). Coating compositions with a varying AAR/HAFA ratio have been prepared and
their various film properties have been studied and compared with the conventional butylated melamine formaldehyde (MF) based
systems. The study reveals that HAFA can be used successfully as a crosslinking agent for AAR in baking systems. In addition
to other technical advantages, the use of HAFA is environmentally friendly as no toxic volatiles are evolved during curing
reaction, unlike in MF-cured systems.
Department of Industrial Chemistry, Vallabh Vidyanagar, Gujarat 388 120 India.
Hyderabad, India. 相似文献
185.
186.
A detailed analysis of different types of gravity distribution devices, designed to split on-site wastewater effluent equally between percolation trenches, has been carried out both in the laboratory and also in the field under realistic loading conditions. Five different types of distribution device have been compared: a V-notch distribution box, stilling chamber box, T-splitters with and without baffles and tipping bucket device. The trials carried out in the laboratory with clean water showed that flow distribution for all devices was sensitive to both the off-level installation angles and variable flow rates, with the most stable performance achieved using the T-splitters with baffles and tipping bucket devices. In parallel to this, the on-site flow regime experienced at two sites was continuously monitored using a tipping bucket and data-logger over eighteen month periods, finding that the most common flow rates at the distribution unit were in the range of 0.1-2.5 L/min. The on-site performance of these devices receiving both septic tank and secondary treated effluent showed that significant solid deposition and biofilm development had severely affected the equal distribution between the trenches, hence highlighting the need for regular maintenance to ensure efficient performance over time after installation. 相似文献
187.
Strong blue fluorescence at 487 nm corresponding to the (1)G(4) ? (3)H(6) transition was generated from Tm(3+)-doped lutetium aluminum garnet on excitation with a 618-nm dye laser as a result of a photon-avalanche upconversion mechanism. 相似文献
188.
Jeydmer Aristizabal Badr Omrane Clint Landrock Sasan Vosoogh-Grayli Yindar Chuo Jasbir N. Patel Bozena Kaminska Carlo Menon 《Journal of Electronic Testing》2011,27(3):403-410
An improved Tungsten light source system for photovoltaic cell testing made from low-cost, commercially available materials is presented as an alternative to standard expensive testing equipment. In this work, spectral correction of the Tungsten light source is achieved by increasing the color temperature to ??5200 K using inexpensive commercially available filters. Spectral measurements of the enhanced light source reveal that a better spectrum match towards the solar spectrum is achieved than what has been previously demonstrated. Specifically, the improved solar spectrum match is achieved by substantial filtering of the infrared range. The proposed setup is used to evaluate the performance of both silicon and organic based photovoltaic cells. 相似文献
189.
Dinesh K. Patel Bathula Vishwanadh Vasanthakumaran Sudarsan Shailendra K. Kulshreshtha 《Journal of the American Ceramic Society》2013,96(12):3857-3861
BaTiO3 and BaSnO3 samples doped with Eu3+ ions were prepared using glycine‐nitrate gel combustion method. Relative intensities and line shapes of magnetic dipole allowed 5D0 → 7F1 and electric dipole allowed 5D0 → 7F2 transitions of Eu3+ from the hosts, BaTiO3 and BaSnO3, are significantly different. Based on detailed structural investigations, it is confirmed that synthesizedBaTiO3 sample is tetragonal with no center of symmetry around Ba2+ ions. Unlike this BaSnO3 is cubic with centrosymmetric Ba2+ site. From X‐ray diffraction and experimentally obtained Judd–Ofelt parameters (Ω2 and Ω4 values), it is confirmed that in BaTiO3 there is a decrease in the average Ba–O and Ba–Ba distances compared with that in BaSnO3. This leads to higher Eu–O bond polarizability and adds to the distortion in its environment around Eu3+ in BaTiO3:Eu compared with BaSnO3:Eu. This is responsible for the observed difference in the luminescence properties. 相似文献
190.
ZT Shi V Afzal B Coller D Patel JA Chasis M Parra G Lee C Paszty M Stevens L Walensky LL Peters N Mohandas E Rubin JG Conboy 《Canadian Metallurgical Quarterly》1999,103(3):331-340
A diverse family of protein 4.1R isoforms is encoded by a complex gene on human chromosome 1. Although the prototypical 80-kDa 4.1R in mature erythrocytes is a key component of the erythroid membrane skeleton that regulates erythrocyte morphology and mechanical stability, little is known about 4.1R function in nucleated cells. Using gene knockout technology, we have generated mice with complete deficiency of all 4.1R protein isoforms. These 4.1R-null mice were viable, with moderate hemolytic anemia but no gross abnormalities. Erythrocytes from these mice exhibited abnormal morphology, lowered membrane stability, and reduced expression of other skeletal proteins including spectrin and ankyrin, suggesting that loss of 4. 1R compromises membrane skeleton assembly in erythroid progenitors. Platelet morphology and function were essentially normal, indicating that 4.1R deficiency may have less impact on other hematopoietic lineages. Nonerythroid 4.1R expression patterns, viewed using histochemical staining for lacZ reporter activity incorporated into the targeted gene, revealed focal expression in specific neurons in the brain and in select cells of other major organs, challenging the view that 4.1R expression is widespread among nonerythroid cells. The 4.1R knockout mice represent a valuable animal model for exploring 4.1R function in nonerythroid cells and for determining pathophysiological sequelae to 4.1R deficiency. 相似文献