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为害赞比亚野生芒果树的病虫害

植物检疫 1987年第4期 275-276页

作者： i.javaid 许允芝

赞比亚的东部、西部以及罗布拉省(Lu-apula)到处生长着芒果树。多数芒果树既不用施肥也不用灌溉,而且对病虫害不进行防治,除了由安哥斯(1964)列出一个芒果病虫害的名录外,对赞比亚为害野生芒果树的为害原因似乎很少研究。这次研究的目... 详细信息

赞比亚的东部、西部以及罗布拉省(Lu-apula)到处生长着芒果树。多数芒果树既不用施肥也不用灌溉,而且对病虫害不进行防治,除了由安哥斯(1964)列出一个芒果病虫害的名录外,对赞比亚为害野生芒果树的为害原因似乎很少研究。这次研究的目的是对生长在赞比亚很多地区野生与半野生芒果树各部位的主要生物的为害因素。

关键词：芒果树赞比亚病虫害病虫草害

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赞比亚芒果园的植保措施

热带作物译丛 1987年第3期 32-35页

作者： i.javaid 莫善文

本文描述了赞比亚芒果的炭疽病、白粉病、叶疫病、疮痂病、畸形病、根腐病、线虫、介壳虫、果蝇、苹条小卷蛾和核象(虫甲)等病虫害,并介绍了这些病虫害的防治措施。

关键词：芒果园白粉病炭疽病芒果树卢萨卡赞比亚

Phase Noise Quenching in a Four-Level Laser

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Chinese Physics Letters 2010年第3期27卷 184-187页

作者： javaid Anwar Department of Physics COMSATS Institute of Information Technology Islamabad Pakistan

in the presence of usual transmission losses, it is shown that phase noise in a four-level laser can be reduced below the Schawlow-Townes limit when lasing levels are coupled to a squeezed vacuum reservoir. The squeezed vacuum coupled to the lasing mode modifies the phase diffusion rate and dominates the contribution from transmission losses. it is predicted to obtain phase stability in the system and phase noise vanishes for larger squeezing. Gain of the laser remains positive under these conditions.

关键词： Optics quantum optics and lasers

Progress in twin roll casting of magnesium alloys: A review

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Journal of Magnesium and Alloys 2021年第2期9卷 362-391页

作者： Amjad javaid Frank Czerwinski CanmetMATERiALS Natural Resources CanadaHamiltonOntarioL8P 0A5Canada

Twin roll casting was commercialized for a strip production from ferrous and non-ferrous alloys in the 1950 s;however,its application to magnesium has proven difficult and still creates major *** report describes global efforts in expanding manufacturing capabilities of magnesium sheet through twin roll casting path,offering many benefits,including a reduction in number of processing steps and energy *** addition to hardware design,alloy transformation during processing,product microstructure and properties,examples of successful solutions along with present technology and knowledge limitations are discussed.A particular attention is paid to developments at Canmet MATERiALS,having the only in North America pilot scale twin roll casting facility,devoted to *** are described that aim at design of new magnesium alloys,which could take advantage of unique processing conditions during twin roll casting and contribute to the overall progress in magnesium sheet manufacturing.

关键词： Twin roll casting Magnesium alloys Solidification Magnesium sheet

Braids with Trivial Simple Centralizer

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Algebra Colloquium 2015年第4期22卷 561-566页

作者： U. Ali F. Azam i. javaid A. Haider Center for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya University Multan Pakistan Department of Mathematics Jazan University Jazan Saudi Arabia

in this paper, we prove that the n-simple braid divisible by the generators xi for all 2 ≤ i ≤n - 2 has trivial simple centralizer. Consequently, the commuting graph defined on the set of simple braids is disconnect... 详细信息

关键词： simple braid simple centralizer commuting graph

A Novel Action Transformer Network for Hybrid Multimodal Sign Language Recognition

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Computers, Materials & Continua 2023年第1期74卷 523-537页

作者： Sameena javaid Safdar Rizvi Department of Computer Sciences School of Engineering and Applied SciencesBahria UniversityKarachi CampusKarachiPakistan

Sign language fills the communication gap for people with hearing and speaking *** includes both visual modalities,manual gestures consisting of movements of hands,and non-manual gestures incorporating body movements including head,facial expressions,eyes,shoulder shrugging,*** both gestures have been detected;identifying separately may have better accuracy,butmuch communicational information is *** sign language mechanism is needed to detect manual and non-manual gestures to convey the appropriate detailed message to *** novel proposed system contributes as Sign LanguageAction Transformer Network(SLATN),localizing hand,body,and facial gestures in video *** we are expending a Transformer-style structural design as a“base network”to extract features from a spatiotemporal *** impulsively learns to track individual persons and their action context inmultiple ***,a“head network”emphasizes hand movement and facial expression simultaneously,which is often crucial to understanding sign language,using its attention mechanism for creating tight bounding boxes around classified *** model’s work is later compared with the traditional identification methods of activity *** not only works faster but achieves better accuracy as *** achieves overall 82.66%testing accuracy with a very considerable performance of computation with 94.13 Giga-Floating Point Operations per Second(G-FLOPS).Another contribution is a newly created dataset of Pakistan Sign Language forManual and Non-Manual(PkSLMNM)gestures.

关键词： Sign language gesture recognition manual signs non-manual signs action transformer network

Effect of hot rolling on microstructure and properties of the ZEK100 alloy

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Journal of Magnesium and Alloys 2019年第1期7卷 27-37页

作者： Amjad javaid Frank Czerwinski CanmetMATERiALS 183 Longwood Road SouthHamiltonOntario L8P 0A5Canada

Attempts to expand manufacturing capabilities of magnesium-based sheet materials are *** as-cast ZEK100(Mg-1.2Zn-0.35Zr-0.17Nd,in wt%)magnesium alloy was subjected to hot rolling at temperatures from 350℃to 450℃using the laboratory 50 ton reversible mill with preheated rolls to manufacture the 1.5-1.7 mm thick *** rolling temperature affected the sheet properties and an increase in the rolling temperature from 250 to 450℃caused reduction of tensile strength from 257 to 228 MPa ac-companied by a reduction in tensile yield stress from 237 to 185 *** the same time,the alloy elongation increased from 17 to 21%.For the same rolling temperature range,the compressive strength reduced from 418 to 351 *** post-rolling annealing at 450℃led to reduction of both tensile and compressive properties with the largest changes corresponding to the rolling temperature of 350°*** correlation between the alloy grain size after rolling and the sheet properties was established where a reduction in grain size was accompanied by an increase of both the tensile/compressive strength and yield *** on Hall-Petch relationship and an average grain size the correlation developed in this study may be used as the prediction model for properties of the hot rolled magnesium *** results are discussed in terms of recent developments in magnesium sheet alloys and the vital role played in this process by rare earth elements.

关键词： Magnesium alloys Hot deformation Microstructure Rare earths Sheet rolling

Phytodiversity and medicinal plant distribution in pasturelands of North Western Himalaya in relation to environmental gradients

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Journal of Mountain Science 2019年第4期16卷 884-897,955-963页

作者： javaid M.DAD Central institute of Temperate Horticulture

This study aimed at elucidating phytodiversity of pasturelands of North-western Kashmir Himalayan biotic province in relation to various environmental gradients, with added focus on assessing distribution of important threatened medicinal plant taxa across surveyed pasturelands. A total of 16 sites that spanned across a broad altitudinal gradient(2502-4120 m) were selected. Phytosociological data like density, cover, frequency and abundance of vascular flora were collected and processed using gradient analysis. Soil moisture, nitrogen, organic carbon, acidity and electrical conductivity, altitude, degree of slope and human disturbance were recorded from each site. Analysis of species composition showed a total of 293 species of vascular plants, belonging to 192 genera and 64 families recorded from surveyed sites. Rank abundance exhibited that majority of species are locally rare and patchily distributed, with over 60% of species recording frequencies between 0%-20% and none showing frequencies more than 80%. Species richness showed significant variations and ranged from 20(Parihasmaidan) to 114(Nagbarren) for macro and 3.53±2.11(Thajwas) to 8.76± 1.01(Marsar) for micro-scale of measurement. The ShannonWiener(H') and Simpson's diversity(Ds) indices also varied greatly and were recorded highest(H'= 2.76 & Ds= 0.36) for Marsar and lowest(0.87 & 0.62) for Parihasmaidan. The diversity attributes suggested that pasturelands with lower species richness and diversity on macro-scale were not always species poor and less diverse on micro-measurement scale. The life form groupings highlighted the hemicryptophytic character of vegetation and species with highest importance value index were Sibbaldia cuneata(5.71), Rumex nepalensis(2.89), Juniperus wallichiana(2.88), Cynodon dactylon(2.83), Poa annua(2.49) and Sambucus wightiana(2.41). The results of canonical correspondence analysis showed that effect of altitude and anthropogenic disturbance was overriding and among various en

关键词： Anthropogenic disturbance Kashmir Himalaya Medicinal plants Mountain grasslands

Changes in soil organic carbon,nitrogen and sulphur along a slope gradient in apple orchard soils of Kashmir Himalaya

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Journal of Mountain Science 2021年第9期18卷 2377-2387页

作者： javaid M DAD Lotfollah ABDOLLAHi Department of Botany University of KashmirHazratbalSrinagar(J&K)India Faculty of Agriculture Payame Noor UniversityTehranP.O.Box 19395-3697Iran

Accumulation and losses of soil organic carbon(SOC),total nitrogen(TN)and sulphur(S)influence food security and global ***,their spatial distribution and variability at regional scale,and their relation to topographical variables are of great *** this study,the variability of SOC,TN and S content was evaluated in apple orchard soils of Kashmir region,at three depths(D1:0-10,D2:10-20,and D3:20-30 cm)on slope gradient i.e.:flat,medium,and *** an increase in slope,a significant decrease of SOC and TN was observed,with concentration of SOC and TN recorded highest(14.3±2.06 g kg-1&0.97±0.35 g kg-1)in flat slope orchards and lowest(9.6±2.07 g kg-1&0.84±0.41 g kg-1)in high slope *** stock basis,the values recorded for flat,medium,and high slope orchards,for SOC and TN were 54.62±4.24 Mg ha-1&0.38±0.06 Mg ha-1,44.13±5.11 Mg ha-1&0.32±0.09 Mg ha-1,and 38.73±5.94 Mg ha-1&0.28±0.10,*** differences for S concentration and stocks were modest,with flat(0.21±0.15 mg kg-1&0.09±0.0.003 Mg ha-1)>high(0.16±0.07 mg kg-1&0.06±0.007 Mg ha-1)>medium(0.12±0.04 mg kg-1&0.075±0.009 Mg ha-1).Across slopes,SOC,TN and S decreased with increasing soil depth,suggesting clear downward ***,SOC and TN increased with the increase of altitude,precipitation and clay content while its relationship with soil acidity and soil bulk density was *** findings may provide scientific basis to structure agricultural development plans or prioritize regions for soil conservation efforts.

关键词： Apple orchards Slope Soil organic carbon Sulphur Total nitrogen Soil bulk density