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Assessment of Forest Growing Stock of Timergara Forest Subdivision, Dir Lower Forest Division

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Open Journal of Ecology 2015年第11期5卷 537-543页

作者： Majid Ullah Amjad Ali Khan Aamir Saleem sajjad saeed Umar Wahab Department of Forestry and Range Management PMAS Arid Agriculture University Rawalpindi Pakistan Department of Environmental Science University of Haripur Haripur Pakistan

The present study was aimed to assess the growing stock of Timergara forest subdivision which was a part of Dir lower forest division (Pakistan). The study area was divided into two different climatic zones (i.e. sub-tropical sub humid and sub-humid temperate zones) on the basis of altitudinal considerations. A total of 43 sample plots are taken in the forest area of 8480 hectare with random sampling technique representing 0.5% of the total forest area. Each sample plot size was of one hectare. In each 100 × 100 m (1 ha plot), number of trees, diameter, age, height, increment, form factor and volume were measured. An interrelation between the diameter (independent variable) and all the other dependent variables (volume, increment and height) were found. At the end, volume tables were made which suited the local conditions as the ones used before were not suited to the local conditions.

关键词： Growing Stock Volume Tables Sub Tropical Sub Humid Dependent Variables Independent Variables

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遥感数据结合地统计学方法在林业中的应用

世界林业研究 2018年第3期31卷 34-40页

作者：张博孙玉军 sajjad saeed 周来陈丽萍张雅馨北京林业大学森林资源和环境管理国家林业局重点开放性实验室

在林业研究中,具有空间属性的林业数据分析、建模和预测越来越受到关注。遥感技术与地统计学方法相结合,提供了大尺度空间格局分析、森林资源动态监测和预测的方法。文中简单介绍了遥感技术与地统计学的方法和特点,从监测与分类、估计... 详细信息

在林业研究中,具有空间属性的林业数据分析、建模和预测越来越受到关注。遥感技术与地统计学方法相结合,提供了大尺度空间格局分析、森林资源动态监测和预测的方法。文中简单介绍了遥感技术与地统计学的方法和特点,从监测与分类、估计与模拟2个方面综述地统计学结合遥感技术在林业中的应用,并针对遥感数据结合地统计学方法在林业研究中存在的问题加以讨论。

关键词：地统计学遥感数据空间效应变异函数克里格

The Carbon Sinks and Mitigation Potential of Deodar (<i>Cedrus deodara</i>) Forest Ecosystem at Different Altitude in Kumrat Valley, Pakistan

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Open Journal of Forestry 2018年第4期8卷 553-566页

作者： Adnan Ahmad Muhammad Amir Abdul Mannan sajjad saeed Sher Shah Sami Ullah Rahman Uddin Qijing Liu Department of Forest Sciences Beijing Forestry University Beijing China Shaheed Benazir Bhutto University Sheringal Dir Upper Pakistan Beijing Key Laboratory of Precision Forestry Beijing Forestry University Beijing China

Forest carbon monitoring and reporting are critical for informing global climate change assessment. The regional estimates of forest carbon attached greater attention, to assess the role of forest in carbon mitigation. Here using field inventory, we examined the carbon sink and mitigation potential of monospecific Deodar forest in the Kumrat valley, of Hindu Kush Himalaya, Region of Pakistan, at a different elevation. The elevation of monospecific Deodar forest ranges from 2300 to 2700 m (a.s.l). We divided the forest into three elevation classes (that is 2300 - 2400 m (EI) 2400 - 2500 m (EII) and 2500 - 2700 m (EIII) a.s.l respectively). In each elevation class, we laid out 09 sample plots (33*33 m2) for measuring carbon values in living tree biomass (LT), soil (SC), litter, dead wood, cone (LDWC) and understory vegetation (USV). Our results showed that the carbon density at EI was 432.37 ± 277.96 Mg·C-1, while the carbon density at EII and EIII was 668.35 ± 323.94 and 1016.79 ± 542.99 Mg·C-1 respectively. Our finding revealed that the carbon mitigation potential of the forest increases with increasing elevation. Among the different elevation classes, EIII stored significantly higher carbon due to the dominance of mature, old age, larger trees, and the minimum anthropogenic disturbance, whereas EI stored statistically lower carbon because of maximum anthropogenic disturbance, which resulted in the removal of mature and over-mature trees. Furthermore, our correlation analysis between tree height and carbon stock and basal area and LT carbon, underlines that the basal area is the stronger predictor of LT carbon estimation than height. Overall our results highlight that deodar forest stored 716.94 ± 462.06 Mg?C·ha-1. However, the rehabilitation, preservation and sustainable management of disturb forest located at a lower elevation could considerably improve carbon mitigation potential.

关键词： Deodar Forest Elevation Carbon Sinks Mitigation Potential

Competitive role of nitrogen functionalities of N doped GO and sensitizing effect of Bi_(2)O_(3)QDs on TiO_(2)for water remediation

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Journal of Environmental Sciences 2021年第10期33卷 107-119页

作者： Saima Noor Shamaila sajjad sajjad Ahmed Khan Leghari Cristina Flox saeed Ahmad International Islamic University Islamabad 44000Pakistan Department of Chemistry and Materials Science Aalto UniversityEspoo 16100Fl-00076Finland Pakistan Institute of Engineering and Applied Sciences Islamabad 44000Pakistan Department of Applied Physics Aalto UniversityEspoo 15100Fl-00076Finland

The promising solar irradiated photocatalyst by pairing of bismuth oxide quantum dots(BQDs)doped TiO_(2)with nitrogen doped graphene oxide(NGO)nanocomposite(NGO/BQDs-TiO_(2))was *** was used for degradation of organic pollutants like 2,4-dichlorophenol(2,4-DCP)and stable dyes,*** B and Congo Red.X-ray diffraction(XRD)profile of NGO showed reduction in oxygenic functional groups and restoring of graphitic crystal *** characteristic diffraction peaks of TiO_(2)and its composites showed crystalline anatase TiO_(2).Morphological images represent spherical shaped TiO_(2)evenly covered with BQDs spread on NGO *** surface linkages of NO-O-Ti,C-O-Ti,Bi-O-Ti and vibrational modes are observed by Fourier transform infrared spectroscopy(FTIR)and Raman *** and NGO modified TiO_(2)results into red shifting in visible region as studied in diffused reflectance spectroscopy(DRS).NGO and BQDs in TiO_(2)are linked with defect centers which reduced the recombination of free charge carriers by quenching of photoluminescence(PL)intensities.X-ray photoelectron spectroscopy(XPS)shows that no peak related to C-O in NGO/BQDs-TiO_(2)is *** indicated that doping of nitrogen into GO has reduced some oxygen functional *** functionalities in NGO and photosensitizing effect of BQDs in ternary composite have improved photocatalytic activity against organic *** byproducts during photo degradation process of 2,4-DCP were studied through high performance liquid chromatography(HPLC).Study of radical scavengers indicated that O_(2)^(·-) has significant role for degradation of 2,*** investigations propose that fabricated nanohybrid architecture has potential for degradation of environmental pollutions.

关键词： Bi_(2)O_(3)quantum dots Nitrogen doped graphene oxide Nitrogen defects TiO_(2) 2,4-Dichlorophenol Water treatment

Reconfigurable Sensing Time in Cooperative Cognitive Network Using Machine Learning

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Computers, Materials & Continua 2023年第3期74卷 5209-5227页

作者： Noor Gul saeed Ahmed Su Min Kim Muhammad sajjad Khan Junsu Kim Department of Electronics Engineering Korea Polytechnic UniversityGyeonggi-do15073Korea Department of Electronics University of PeshawarPeshawar25120Pakistan Deparment of Electrical Engineering Mirpur University of Science of TechnologyAJ&KMirpur10250Pakistan Department of Electrical Engineering International Islamic UniversityIslamabad44000Pakistan

A cognitive radio network(CRN)intelligently utilizes the available spectral resources by sensing and learning from the radio environment to maximize spectrum *** CRNs,the secondary users(SUs)opportunistically access the primary users(PUs)***,unambiguous detection of the PU channel occupancy is the most critical aspect of the operations of *** spectrum sensing(CSS)is rated as the best choice for making reliable sensing *** paper employs machinelearning tools to sense the PU channels reliably in *** sensing parameters are reconfigured to maximize the spectrum utilization while reducing sensing error and cost with improved channel *** fine-k-nearest neighbor algorithm(FKNN),employed in this paper,estimates the number of samples based on the nature of the channel under-specific detection and false alarm probability *** simulation results reveal that the sensing cost is suppressed by reducing the sensing time and exploiting the traditional fusion rules,validating the effectiveness of the proposed ***,the global decision made at the fusion center(FC)based on the modified sensing samples,results low energy consumption,higher throughput,and improved detection with low error probabilities.

关键词： Energy detection machine learning k-nearest-neighbor decision tree linear regression throughput energy consumption

Application of Physical Unclonable Function for Lightweight Authentication in Internet of Things

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Computers, Materials & Continua 2023年第4期75卷 1901-1918页

作者： Ahmad O.Aseeri sajjad Hussain Chauhdary Mohammed saeed Alkatheiri Mohammed A.Alqarni Yu Zhuang Department of Computer Science College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAl-Kharj11942Saudi Arabia Department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddahSaudi Arabia Department of Cybersecurity College of Computer Science and EngineeringUniversity of JeddahJeddahSaudi Arabia Department of Software Engineering College of Computer Science and EngineeringUniversity of JeddahJeddahSaudi Arabia Department of Computer Science Texas Tech UniversityLubbockUSA

IoT devices rely on authentication mechanisms to render secure message *** data transmission,scalability,data integrity,and processing time have been considered challenging aspects for a system constituted by IoT *** application of physical unclonable functions(PUFs)ensures secure data transmission among the internet of things(IoT)devices in a simplified network with an efficient time-stamped *** paper proposes a secure,lightweight,cost-efficient reinforcement machine learning framework(SLCR-MLF)to achieve decentralization and security,thus enabling scalability,data integrity,and optimized processing time in IoT *** has been integrated into SLCR-MLF to improve the security of the cluster head node in the IoT platform during transmission by providing the authentication service for device-to-device *** IoT network gathers information of interest from multiple cluster members selected by the proposed *** addition,the software-defined secured(SDS)technique is integrated with SLCR-MLF to improve data integrity and optimize processing time in the IoT *** analysis shows that the proposed framework outperforms conventional methods regarding the network’s lifetime,energy,secured data retrieval rate,and performance *** enabling the proposed framework,number of residual nodes is reduced to 16%,energy consumption is reduced by up to 50%,almost 30%improvement in data retrieval rate,and network lifetime is improved by up to 1000 msec.

关键词： Cyber-physical systems security data aggregation Internet of Things physical unclonable function swarm intelligences

Comparative study of multilayer perceptron-stochastic gradient descent and gradient boosted trees for predicting daily suspended sediment load: The case study of the Mississippi River, U.S.

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International Journal of Sediment Research 2021年第4期36卷 512-523页

作者： Sadra Shadkani Akram Abbaspour saeed Samadianfard sajjad Hashemi Amirhosein Mosavi Shahab S.Band Department of Water Engineering Faculty of Agriculture University of Tabriz Environmental Quality Atmospheric Science and Climate Change Research Group Ton Duc Thang University Faculty of Environment and Labour Safety Ton Duc Thang University Institute of Research and Development Duy Tan University Future Technology Research Center College of Future National Yunlin University of Science and Technology

Monitoring sediment transport is essential for managing and maintaining *** of the sediment load in rivers is fundamental for the study of sediment movement,erosion,and flood *** the current study,three machine learning models-multi-layer perceptron(MLP),multi-layer perceptron-stochastic gradient descent(MLP-SGD),and gradient boosted tree(GBT)-were utilized to estimate the suspended sediment load(SSL) at the ***(SL) and Chester(CH) stations on the Mississippi River,*** evaluation criteria including the Correlation Coefficient(CC),Nash Sutcliffe Efficiency(NSE),Scatter Index(SI),and Willmott’s Index(WI) were utilized to evaluate the performance of the used models.A sensitivity analysis of the models to the input variables revealed that the current day discharge variable had the most effect on the SSL at both stations,but in the absence of current-day discharge data(Qt),a combination of input parameters including SSLt-3,SSLt-2,SSLt-1,Qt-3,Qt-2,Qt-1can be used to estimate the *** comparative outcomes indicated the high accuracy of MLP-SGD-5 model with a CC of 0.983,SI of 0.254,WI of 0.991,and NSE of 0.967 at station CH and the MLP-SGD-6 model with a CC of 0.933,SI of 0.576,WI of 0.961,and NSE of 0.867,respectively,at station *** results of MLP models were improved by SGD ***,the MLP-SGD method is recommended as the most accurate model for SSL estimation.

关键词： Suspended sediment transport Ensemble learning Multilayer perceptron Stochastic gradient descent Machine learning

Synthesis and Characterization of Antimony（III） Complexes of Thioamides, and Crystal Structure of {[Sb（Imt）2Cl2]2（u2-lmt）}Cl2 （Imt=Imidazolidine-2-thione）

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Chinese Journal of Chemistry 2011年第2期29卷 254-258页

作者： Ajaz Humayun Hussain sajjad Altaf Muhammad Stoeckli-Evans Helen Isab Anvarhusein Mahmood Rashid Altaf Shahnila Ahmad saeed Department of Chemistry University of Engineering and Technology Lahore 54890 Pakistan Institute of Physics University of Neuchdtel Rue Emile-Argand 11 CH-2009 Neuchatel Switzerland Department of Chemistry King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia Division of Science and Technology University of Education Township Lahore Pakistan

Antimony（III） complexes of thioamides [thioamides=thiourea （Tu）, N,N＇dimethylthiourea （Dmtu）, tetramethylthiourea （Tmtu）, imidazolidine-2-thione （Imt） and diazinane-2-thione （Diaz）] with the general formulae, Sb（thione）nCl3 （n= 1, 2, 2.5, 3） were prepared and characterized by elemental analysis, IR and NMR （1H, 13C） spectroscopic methods. The spectral data of the complexes are consistent with the coordination of the thiones to antimony（III）. The crystal structure of one of them, {[Sb（Imt）2Cl2]2（u2-Imt）}Cl2 （1）, was determined by X-ray crystallography, which shows that the complex is dinuclear consisting of two [Sb（Imt）2Cl2] units bridged by an Imt molecule. In 1, the antimony atom is bonded to two chlorine atoms, two sulfur atoms of coordinated Imt molecules and one sulfur atom of a bridging Imt molecule. The antimony environment can be considered to be distorted octahedral with one Cl- ion weakly bound to antimony.

关键词： antimony(III) complex thioamide crystal structure spectroscopy

Genome-wide association analysis for stripe rust resistance in spring wheat(Triticum aestivum L.) germplasm

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Journal of Integrative Agriculture 2020年第8期19卷 2035-2043页

作者： Sher MUHAMMAD Muhammad sajjad Sultan Habibullah KHAN Muhammad SHAHID Muhammad ZUBAIR Faisal saeed AWAN Azeem iqbal KHAN Muhammad Salman MUBARAK Ayesha TAHIR Muhammad UMER Rumana KEYANI Muhammad InamAFZAL Irfan MANZOOR Javed Iqbal WATTOO Aziz-ur REHMAN Department of Bioinformatics and Biotechnology GC UniversityFaisalabad 38090Pakistan Department of Biosciences COMSATS University Islamabad(CUI)Islamabad 45550Pakistan Centre of Agricultural Biochemistry and Biotechnology(CABB) University of AgricultureFaisalabad 38000Pakistan Department of Plant Breeding and Genetics University of AgricultureFaisalabad 38000Pakistan Department of Biotechnology Faculty of Life SciencesUniversity of Central PunjabLahore 54000Pakistan Wheat Research Institute Ayub Agricultural Research Institute(AARI)Faisalabad 38950Pakistan

Stripe rust is a continuous threat to wheat crop all over the *** causes considerable yield losses in wheat crop every *** deployment of adult plant resistance(APR)genes in newly developing wheat cultivars is the most judicious strategy to combat this ***,we dissected the genetics underpinning stripe rust resistance in Pakistani wheat *** association panel of 94 spring wheat genotypes was phenotyped for two years to score the infestation of stripe rust on each accession and was scanned with 203 polymorphic *** on D’measure,linkage disequilibrium(LD)exhibited between loci distant up to 45 c ***-trait associations(MTAs)were determined using mixed linear model(MLM).Total 31 quantitative trait loci(QTLs)were observed on all 21 wheat *** QTLs were newly discovered as well as 19 QTLs and 35 previously reported Yr genes were validated in Pakistani wheat *** major QTLs were ***.2 AL and ***.3 BS(PVE,11.9%).Dissection of genes from the newly observed QTLs can provide new APR genes to improve genetic resources for APR resistance in wheat crop.

关键词： wheat Puccinia striiformis LD GWAS MTA PCoA