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Elevational patterns of temperature and humidity in the middle Tianshan Mountain area in Central Asia

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Journal of Mountain Science 2020年第2期17卷 397-409页

作者： Gheyur GHEYRET anwar MOHAMMAT TANG Zhi-yao Institute of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface ProcessesPeking UniversityBeijing 100871China Key Laboratory of Biogeography and Bioresources in Arid Land Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

The vertical distribution of vegetation types along an elevational gradient in mountain areas largely depends on the elevational changes in air temperature and humidity. In this study, we presented the seasonal and diurnal variations in the elevational gradients of air temperature and humidity on the southern and northern slopes in the middle Tianshan Mountain Range using data collected throughout the year via HOBO data loggers. The measurements were conducted at 12 different elevations from 1548 to 3277 m from September 2004 to August 2005. The results showed that the annual mean air temperature decreased along the elevational gradients with temperature lapse rates of(0.71±0.20)°C/100 m and(0.59±0.05)°C/100 m on the northern and southern slopes, respectively. The annual mean absolute humidity significantly decreased with increasing elevation on the northern slope but showed no significant trend on the southern slope. The annual mean relative humidity did not show a significant trend on the northern slope but increased with increasing elevation on the southern slope. The mean air temperature lapse rate exhibited significant seasonal variation, which is steeper insummer and shallower in winter, and this value varied between 0.37°C/100 m and 0.75°C/100 m on the southern slope and between 0.30°C/100 m and 1.02°C/100 m on the northern slope. The mean absolute and relative humidity also exhibited significant seasonal variations on both slopes, with the maximum occurring in summer and the minimum occurring in winter or spring. The monthly diurnal range of air temperature on both slopes was higher in spring than in winter. The annual range of air temperature on the southern slope was higher than that on the northern slope. Our results suggest that significant spatiotemporal variations in humidity and temperature lapse rate are useful when analyzing the relationships between species range sizes and climate in mountain areas.

关键词： Temperature lapse rate Absolute humidity Relative humidity Annual range of temperature Diurnal range of temperature HOBO data loggers

Synthesis and Characterization of Alkaline-Earth Metal (Ca, Sr, and Ba) Doped Nanodimensional LaMnO_(3) Rare-Earth Manganites

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Chinese Physics Letters 2013年第7期30卷 217-220页

作者： Asma Khalid Saadat anwar Siddiqi Affia Aslam School of Physics University of MelbourneParkville VIC 3010Australia Interdisciplinary Research Centre in Biomedical Materials COMSATS Institute of Information TechnologyDefence RoadOff Raiwind RoadLahore-54700Pakistan Department of Physics University of HailHail-30055Saudi Arabia

The substitution of divalent cations of alkaline-earth elements in nanodimensional structures of rare-earth manganites produces advanced materials with potential electrical and magnetic functionalities.A systematic investigation of La_(0.65)A_(0.35)MnO_(3)(A=Ca,Sr,Ba)materials synthesized with a modified citrate route adopting ethanol dehydration has been *** structural and morphological analyses are carried out by using x-ray diffraction and scanning electron microscopy,*** measurements are performed in variation with temperature to study the electrical transport properties which are found to vary with the size of the A-site cationic *** temperature magnetic measurements are carried out to investigate the type of magnetic phase present in *** stability of the magnetic phase and coercivity are found to be dependent on the size of nanocrystallites.

关键词： materials. earth dimensional

Spatially Adaptive Image Restoration Using Fuzzy Punctual Kriging

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Journal of Computer Science & Technology 2007年第4期22卷 580-589页

作者： anwar M.Mirza Asmatullah Chaudhry Badre Munir Faculty of Cornputer Science and Engineering Ghulam Ishaq Khan(GIK)Institute of Engineering Science and Technology Topi-23460SwabiPakistan

We present a general formulation based on punctual kriging and fuzzy concepts for image restoration in spatial domain. Gray-level images degraded with Gaussian white noise have been considered. Based on the pixel local neighborhood, fuzzy logic has been employed intelligently to avoid unnecessary estimation of a pixel. The intensity estimation of the selected pixels is then carried out by employing punctual kriging in conjunction with the method of Lagrange multipliers and estimates of local semi-variances. Application of such a hybrid technique performing both selection and intensity estimation of a pixel demonstrates substantial improvement in the image quality as compared to the adaptive Wiener filter and existing fuzzykriging approaches. It has been found that these filters achieve noise reduction without loss of structural detail information, as indicated by their higher structure similarity indices, peak signal to noise ratios and the new variogram based quality measures.

关键词： image restoration fuzzy logic punctual kriging semivariance structure similarity index adaptive spatial filtering

Achieving Energy Efficiency in Wireless Sensor Networks Using Dynamic Channel Polling and Packet Concatenation

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China Communications 2021年第8期18卷 249-270页

作者： Shama Siddiqui anwar Ahmed Khan Sayeed Ghani Department of Computer Science DHA Suffa UniversityKarachiPakistan Department of Computer Science Institute of Business AdministrationKarachiPakistan Department of Computer Science Sindh Institute of Management&TechnologyKarachiPakistan

There has been a significant interest of researchers to combine different schemes focused on optimizing energy performance while developing aMAC protocol for Wireless Sensor Networks(WSNs).In this paper,we propose to integrate two cross-layer schemes:dynamic channel polling and packet concatenation using a recent asynchronous MAC protocol“Adaptive&Dynamic Polling MAC”(ADPMAC).ADP-MAC dynamically selects the polling interval distribution based on characterization of incoming traffic patterns using Coefficient of variation(CV).Packet Concatenation(PC)refers to combining the individually generated data packets into a single super packet and sending it at the polling ***,the Block Acknowledgement(BA)scheme has been developed for ADP-MAC to work in conjunction with the packet *** proposed schemes have been implemented in Tiny-OS for Mica2 platform and Avrora emulator has been used for conducting *** results have revealed that the performance both in terms of energy&packet loss improves when ADP-MAC is used in conjunction with the additional features of PC&***,the proposed scheme has been compared with a stateof-art packet concatenation primitive PiP(Packet-in-Packet).It has been observed that ADP-MAC supersedes the performance of PiP in terms of PDR(Packet Delivery Ratio)due to better management of synchronization between source and sink.

关键词： energy efficiency concatenation dynamic polling