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The Development Trends and Research Fronts in Orbital Angular Momentum Technology:A Bibliometric Analysis

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China Communications 2023年第2期20卷 289-310页

作者： Saleemullah Memon Xiuping Li kamran Ali Memon Yuhan Huang Junaid Ahmed Uqaili muhammad Ishfaq School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Telecommunication Engineering Quaid-e-Awam University of EngineeringScience&TechnologyPakistan

Orbital angular momentum(OAM)technology,refers to Laguerre-Gaussian(LG)beams,twisted beams,vector/vortex beams,acoustic vortex beams and fractional vortex *** is an emerging and promising technology to improve the communication capacity,spectral efficiency,and anti-jamming capability due to its helical phase fronts and infinite orthogonal *** the OAM research began in the 1990s,the developing trends,current status,issues and characteristics through a systematic observation have not yet been *** paper presents a knowledge-based evolution of OAM research published in the Web of Science(WoS)from 2011 to 2021 using bibliometric analysis in *** results demonstrate that the bandwidth,efficiency,gain,divergence,phase quantization,bulky and complex feeding structures,misalignment,distortion,interferences atmospheric turbulence and diffraction were the key issues found in the OAM *** main research hotspots and categories,influential authors,leading journals,best institutions of OAM show a strong bias in favor of their functions and technology *** research on OAM was mainly performed by the counties that have developed the 5G and now moving towards 6G communications like China,USA and South *** study would serve as an inclusive guide on the future research trends and status especially for the OAM researchers.

关键词： orbital angular momentum(OAM) vortex beams bibliometric analysis CiteSpace

Evaluation of state and community/private forests in Punjab, Pakistan using geospatial data and related techniques

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Forest Ecosystems 2015年第2期2卷 155-167页

作者： naeem Shahzad Urooj Saeed Hammad Gilani Sajid Rashid Ahmad Irfan Ashraf Syed muhammad Irteza World Wide Fund for Nature (WWF) Institute of Geology University of the Punjab International Centre for Integrated Mountain Development (ICIMOD) Department of Land Surveying and Geo-Informatics Hong Kong Polytechnic University

Background： Forests are fundamental in maintaining water supplies, providing economic goods, mitigating climate change, and maintaining biodiversity, thus providing many of the world＇s poorest with income, food and medicine. Too often, forested lands are treated as ＂wastelands＂ or ＂free＂ and are easily cleared for agricultural and infrastructure expansion. Methods： In this paper, the sustainability of two forest ecosystems （state and community/private owned） was evaluated using SPOT-5 satellite images of 2005 and 2011. This study was conducted in a sub-watershed area covering 468 km2, of which 201 km2 is managed by the state and 267 km2 by community/private ownership in the Murree Galliat region of Punjab Province of Pakistan. A participatory approach was adopted for the delineation and demarcation of forest boundaries. The Geographic Object-Based Image Analysis （GEOBIA） technique was used for identification and mapping of ten Land Cover （LC） features. Results： The results show that between the years 2005 to 2011, a total of 55 km2 （24 km2 in state-owned forest and 31 km2 in community/private forest） was converted from forest to non-forest. The conclusion is that conservation is more effective in state-owned forests than in the community/private forests. Conclusions： These findings may help to mobilize community awareness and identify effective initiatives for improved management of community/private forest land for other regions of Pakistan.

关键词： Forest management SPOT-5 satellite images State and community/private owned forests Murree Galliat Pakistan

Crystal Structure Analysis of 1-Hydroxy-3,5-dimethoxy-9H-xanthen-9-one Isolated from Ajuga bracteosa Root Extract and Its Biological Studies

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Chinese Journal of Structural Chemistry 2019年第9期38卷 1519-1529页

作者： AKHTER Kulsoom AHMED Muhammed naeem GHOUS Tahseen RASHEED Basharat TAHIR muhammad Nawaz ARSHAD Ifzan Department of Chemistry The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Chemistry Mirpur University of Science and Technology(MUST)Mirpur-10250Azad Jammu and KashmirPakistan Department of Physics University of SargodhaSargodhaPakistan Department of Chemistry Quaid-i-Azam UniversityIslamabadPakistan

The structure of 1-hydroxy-3,5-dimethoxy-9 H-xanthen-9-one isolated from chloroform extract of Ajuga bracteosa root was analyzed by single-crystal X-ray diffraction. DPPH(1,1-diphenyl-2-picryl hydrazyl), ABTS(2,2?-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities(RSA) and Fe2+ chelating activities were carried out to determine the antioxidant potential of the compound. RSA values for the compound were 96%, 96% and 96% for all the three activities respectively at maximum concentration of the compound(100 μ gmL-1) with the IC50 values of 3.40, 4.86 and 0.10(μ gmL-1). Antidiabetic activities including antiglycation and α-glucosidase inhibition were also performed where the antiglycation activity was performed using two techniques including spectrofluorometric as well as spectrophotometric technique. Spectrofluorometric technique provided 97% antiglycation potential while 92% antiglycation potential was observed by spectrophotometric technique for the isolated compound. The compound at a concentration of 10 μ gmL-1 exhibited 31% α-glucosidase inhibitory potential with IC50 of 15.56 μ gmL-1. Antimicrobial activity data showed that the compound was active against all the studied pathogenic bacteria.

关键词： crystal structure radical scavenging activity antidiabetic activity C–H···π interactions

On the role of optimization algorithms in ownership-preserving data mining

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Frontiers of Information Technology & Electronic Engineering 2018年第2期19卷 151-164页

作者： muhammad kamran Ehsan Ullah MUNIR Department of Computer Science COMSATS Institute of Information Technology

Knowledge extraction from sensitive data often needs collaborative work. Statistical databases are generated from such data and shared among various stakeholders. In this context, the ownership protection of shared data becomes important. Watermarking is emerging to be a very effective tool for imposing ownership rights on various digital data formats. Watermarking of such datasets may bring distortions in the data. Consequently, the extracted knowledge may be inaccurate. These distortions are controlled by the usability constraints, which in turn limit the available bandwidth for watermarking. Large bandwidth ensures robustness; however, it may degrade the quality of the data. Such a situation can be resolved by optimizing the available bandwidth subject to the usability constraints. Optimization techniques, particularly bioinspired techniques, have become a preferred choice for solving such issues during the past few years. In this paper, we investigate the usability of various optimization schemes for identifying the maximum available bandwidth to achieve two objectives：（1） preserving the knowledge stored in the data;（2） maximizing the available bandwidth subject to the usability constraints to achieve maximum robustness. The first objective is achieved with a usability constraint model, which ensures that the knowledge is not compromised as a result of watermark embedding. The second objective is achieved by finding the maximum bandwidth subject to the usability constraints specified in the first objective. The performance of optimization schemes is evaluated using different metrics.

关键词： Information security Optimization Digital fights Watermarking

Gly-LysPred: Identification of Lysine Glycation Sites in Protein Using Position Relative Features and Statistical Moments via Chou’s 5 Step Rule

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Computers, Materials & Continua 2021年第2期66卷 2165-2181页

作者： Shaheena Khanum muhammad Adeel Ashraf Asim Karim Bilal Shoaib muhammad Adnan Khan Rizwan Ali Naqvi kamran Siddique Mohammed Alswaitti Department of Computer Science Lahore University of Management SciencesLahore54792Pakistan Department of Computer Science University of Management and TechnologyLahore54770Pakistan School of Computer Science Minhaj University LahoreLahore54770Pakistan Department of Computer Science Lahore Garrison UniversityLahore54000Pakistan Department of Unmanned Vehicle Engineering Sejong UniversitySeoulKorea Department of Information and Communication Technology School of Electrical and Computer EngineeringXiamen University MalaysiaSepang43900Malaysia

Glycation is a non-enzymatic post-translational modification which assigns sugar molecule and residues to a *** is a clinically important attribute to numerous age-related,metabolic,and chronic diseases such as diabetes,Alzheimer’s,renal failure,*** of a non-enzymatic reaction are quite challenging in *** identification in labs is a very costly and timeconsuming *** this research,we developed an accurate,valid,and a robust model named as Gly-LysPred to differentiate the glycated sites from non-glycated *** techniques using position relative features are used for feature *** algorithm named as a random forest with some preprocessing techniques and feature engineering techniques was developed to train a computational *** types of testing techniques such as self-consistency testing,jackknife testing,and cross-validation testing are used to evaluate the *** overall model’s accuracy was accomplished through self-consistency,jackknife,and cross-validation testing 100%,99.92%,and 99.88%with MCC 1.00,0.99,and 0.997 *** this regard,a user-friendly webserver is also urbanized to accumulate the whole *** features vectorization methods suggest that they can play a critical role in other web servers which are developed to classify lysine glycation.

关键词： Gly-LysPred PseAAC post-translational modification lysine glycation Chou’s 5 step rule position relative features

Weak stem under shade reveals the lignin reduction behavior

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Journal of Integrative Agriculture 2019年第3期18卷 496-505页

作者： Sajad Hussain Nasir Iqbal PANG Ting muhammad naeem Khan LIU Wei-guo YANG Wen-yu College of Agriculture Sichuan Agricultural University/Key Laboratory of Ecophysiology and Farming System in Southwest ChinaMinistry of AgricultureChengdu 611130P.R.China College of Agriculture Bahauddin Zakariya UniversityBahadur Sub-CampusLayyah 31200Pakistan

Shades caused by neighboring tall plants in intercropping systems and weak sunlight are constraints in yield optimization. Shade influences many aspects of plant growth and development, leading to weak stems and susceptibility to lodging. The plant cell wall is composed of certain proteins that allow the walls to stretch out, a process called cell wall loosening. Shade affects anatomical, morphological, and physiological traits of plants, thus reducing the physical strength of the stem in crops by changing the loosening of cell walls. Flexibility of cells facilitates further modifications such as wall loosening. In addition, shade stress causes increased internode length, and reduced xylem synthesis and photosynthesis. In shaded plants, lignin deposition in vascular bundles and sclerenchyma cells of stems is decreased. Lignin is a light sensitive phenolic compound and shading decreases the transcript abundance of several phenolic compound(flavone and lignin) related genes. Shading significantly influences the metabolic activities of phenylalanine ammonia-lyase(PAL), peroxidase(POD), 4-coumarate: CoA ligase(4 CL), and cinnamyl alcohol dehydrogenase(CAD) involved in lignin biosynthesis. Furthermore, suppression of lignin biosynthesis activities by abiotic stresses causes abnormal phenotypes such as collapsed xylem, bent stems, and growth retardation. In this review, the underlying mechanisms illustrate that under shading conditions reduced lignin content results in slender, weak, and unstable stems. The objective of this review is to elaborate lignin biosynthesis and its variability under stressful environmental conditions, especially in shade stress environments. The effects of shade on stem lignin metabolism are discussed on the morphogenetic, physiological, and proteomic levels.

关键词： lignin biosynthesis shade stress lodging stem strength

Synthesis and Structural Investigations of New 4-Hexyl-1-(4-nitrophenyl)-1-H-1,2,3-triazole:An Experimental and Theoretical Insight

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Chinese Journal of Structural Chemistry 2015年第12期34卷 1830-1840页

作者： muhammad naeem Ahmed KHAWAJA Ansar Yasin TARIQ Mahmood FATIMA Wasim muhammad Haleem Khan M.NAWAZ Tahir SAFEENA Zafar SHAISTA Anjum Department of Chemistry The University of Azad Jammu and Kashmir Department of Chemistry COMSATS Institute of Information Technology Department of Chemistry Women University Bagh Azad Kashmir Department of Physics University of Sargodha

The title compound, 4-hexyl-1-（4-nitrophenyl）-1-H-1,2,3-triazole （CI4HIsN402）, was synthesized using one-pot strategy via click reaction and the structure was characterized mainly by single-crystal X-ray diffraction, NMR, FT-IR and MS. C14H18N4O2 was crystallized from an EtOH/EtOAc solution in triclinic system, space group PI, with a = 5.3679（3）, b = 7.5499（5）, c = 17.5534（11） A, a = 92.360（4）, β = 90.359（4）, γ = 98.864（4）°, V （A3） = 702.24（8）, Z = 2, crystal size （mm） = 0.42 × 0.26 × 0.18, Rint = 0.096. Packing diagram indicates that there is dimeric interaction between two units via N（3）...H（6）. The crystal structure of the title compound （1） is stabifized by intermolecular interactions. In addition, X-ray analys!s also reveals C-H…π and π-π interactions in the molecule. Theoretical investigations were performed by using Gaussian 09 software at the B3LYP/6, 31G （d,p）level of density,finctional theory （DFT）.to compare the theoretical results with the experimental and to probe structural properties. The molecular electrostatic potential （MEP） mapped over the entire stabilized geometry of the molecule indicated their chemical reactivities. Furthermore, frontier molecular orbital （electronic properties） was computed at the same level of DFT as used. forenergy minima structure.

关键词： click chemistry disubstituted triazole X-ray DFT MEP frontier molecurar orbital

Impact of foreign direct investment on the exports of five major sectors of Pakistan’s economy:A governance perspective

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Chinese Journal of Population,Resources and Environment 2023年第3期21卷 181-188页

作者： kamran Farid Tahir Mahmood muhammad Mumtaz Sarfraz Hussain Ansari Department of Economics Quaid-i-Azam UniversityIslamabad45320Pakistan Department of Economics Karakoram International UniversityGilgit15100Pakistan Department of Economics University of Religions and DenominationsQom37100Iran Department of Public Administration Fatima Jinnah Women UniversityRawalpindi46000Pakistan National Defence University Islamabad 44230Pakistan

This study investigates and analyses empirically the impact of Foreign Direct Investment(FDI)inflows on the exports for a panel series of five large-scale manufacturing industries of Pakistan during the period *** this purpose,we establish export production function as based on endogenous growth theory in which role of FDI is considered as additional determinant of *** Pedroni residual-based co-integration test and Error Correction Model(ECM)are applied for the long and short-run *** residual based approach highlighted that human capitals,domestic capitals,foreign direct investments,exports,and domestic sales are co-integrated in the long *** to results of ECM,coefficient of FDI appears to have statistical significant impact on exports and has a positive sign in the long ***,FDI does not contribute to export growth in the short run but it takes time to influence the growth patterns of the *** the basis of theoretical notion of endogenous growth theory,long-run coefficient of FDI may be interpreted as evidence in favour of the hypotheses that FDI has an impact on exports via export ***,it can be concluded that“FDI-based endogenous growth theory”is valid in the case of Pakistan.

关键词： FDI Exports Panel Data Pakistan

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一种引入互斥关系的功能单元分配算法

北京理工大学学报 2005年第10期25卷 885-889页

作者：程利新石峰 muhammad kamran 北京理工大学信息科学技术学院计算机科学工程系北京100081

为使条件分支数据通道中功能单元的分配结果得到进一步优化,在数据流图操作相容性分析中引入操作间互斥关系,并构建基于图论的分配模型.使用团划分算法在该模型上进行功能单元分配,同时提出一种针对功能单元分配问题的团划分启发式方法... 详细信息

为使条件分支数据通道中功能单元的分配结果得到进一步优化,在数据流图操作相容性分析中引入操作间互斥关系,并构建基于图论的分配模型.使用团划分算法在该模型上进行功能单元分配,同时提出一种针对功能单元分配问题的团划分启发式方法.不仅提高了团划分算法求解功能单元分配问题的计算结果一致性,而且使算法的收敛速度得以提高.根据实验结果,该算法得到的数据通道中所需功能单元平均减少了41%,同时执行速度加快了50%.

关键词：互斥关系功能单元分配团划分