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Thermal Decomposition Kinetics of Some Di- and Triorganotin（IV） Carboxylates Derived from para-Nitrophenylethanoic Acid

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Chinese Journal of Chemistry 2011年第7期29卷 1359-1365页

作者： Danish, Muhammad Ahmad, Nazir ali, saqib Muhammad, Niaz Department of Chemistry University of Gujrat Hafiz Hayat Campus Gujrat-50700 Pakistan Department of Chemistry University of Sargodha Srgoadha 40100 Pakistan Department of Chemistry Quaid-i-Azam University Islamabad-45320 Pakistan

Thermogravimetric （TG） investigations of organotin（IV） carboxylates with the general formula RmSnL4-m （where R=CH3, C2H5, n-C4H9, C6H5, cyclo-C6H11, n-C8H17, m=2, 3, and L=para-nitrophenylethanoate anion） have been performed. Derivative thermogravimetry （DTG） and differential thermal analysis （DTA） techniques, Horowitz-Metzger method and the fundamental thermodynamic relations are used to evaluate the thermokinetic pa- rameters of each thermal degradation pattern. Results reveal that the thermal stability is functional to Sn--C and Sn--O bonds. In the case of R2SnL2, activation energy, reaction order and pre-exponential factor associated with the bulk degradation processes increase as the alkane chain length increases. Hence, Oct2SnL2 is thermally more stable than Bu2SnL2, which in turn is more resistant to thermal dissociation than Et2SnL2. The same phenomenon is not observed for R3SnL compounds because their degradation is highly irregular. Furthermore, R2SnL2 has larger values of kinetic parameters than those of corresponding triorganotin（IV） para-nitrophenylethanotes. Thermodynamic parameters of these compounds also reinforce the above facts.

关键词： organotin(IV) caroxylate thermogravimetry decomposition kinetics activation energy thermodynamics

A Levenberg–Marquardt Based Neural Network for Short-Term Load Forecasting

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Computers, Materials & Continua 2023年第4期75卷 1783-1800页

作者： saqib ali Shazia Riaz Safoora Xiangyong Liu Guojun Wang School of Computer Science Guangzhou University Guangzhou510006Guangdong ProvinceChina Department of Computer Science University of AgricultureFaisalabad38000Pakistan Department of Computer Science Government College Women UniversityFaisalabad38000Pakistan

Short-term load forecasting (STLF) is part and parcel of theefficient working of power grid stations. Accurate forecasts help to detect thefault and enhance grid reliability for organizing sufficient energy *** ranges from an hour ahead prediction to a day ahead prediction. Variouselectric load forecasting methods have been used in literature for electricitygeneration planning to meet future load demand. A perfect balance regardinggeneration and utilization is still lacking to avoid extra generation and misusageof electric load. Therefore, this paper utilizes Levenberg–Marquardt(LM) based Artificial Neural Network (ANN) technique to forecast theshort-term electricity load for smart grids in a much better, more precise,and more accurate manner. For proper load forecasting, we take the mostcritical weather parameters along with historical load data in the form of timeseries grouped into seasons, i.e., winter and summer. Further, the presentedmodel deals with each season’s load data by splitting it into weekdays andweekends. The historical load data of three years have been used to forecastweek-ahead and day-ahead load demand after every thirty minutes makingload forecast for a very short period. The proposed model is optimized usingthe Levenberg-Marquardt backpropagation algorithm to achieve results withcomparable statistics. Mean Absolute Percent Error (MAPE), Root MeanSquared Error (RMSE), R2, and R are used to evaluate the model. Comparedwith other recent machine learning-based mechanisms, our model presentsthe best experimental results with MAPE and R2 scores of 1.3 and 0.99,respectively. The results prove that the proposed LM-based ANN modelperforms much better in accuracy and has the lowest error rates as comparedto existing work.

关键词： Short-term load forecasting artificial neural network power generation smart grid Levenberg-Marquardt technique

Group-Based Handover Authentication Scheme for Machine-to-Machine Communication in LTE-A Network

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Group-Based Handover Authentication Scheme for Machine-to-Ma...

作者： ali saqib 南京理工大学

学位级别：硕士

机器对机器通信因为其必要性和实时网络应用而被证明是LTE-A网络中的重要实体。机器对机器(M2M)或机器类型通信(MTC)也正在成为未来移动通信新技术时代的里程碑。通过实时网络应用,MTC在短时间内获得了极大的关注。MTC是设备之间通信的... 详细信息

机器对机器通信因为其必要性和实时网络应用而被证明是LTE-A网络中的重要实体。机器对机器(M2M)或机器类型通信(MTC)也正在成为未来移动通信新技术时代的里程碑。通过实时网络应用,MTC在短时间内获得了极大的关注。MTC是设备之间通信的平均源,其核心网络没有第三方的介入。随着MTC设备的快速增长和使用,安全漏洞的威胁也在增加,而安全是M2M通信中最重要的问题。当大量MTC设备一起请求注册到期望的网络时,单个设备必须通过网络完成其认证过程。同一时间大量设备的接入认证的过程可能遭受严重的信令拥塞,并且不愿意在LTE-A网络上为MTC设备提供鲁棒的安全机制。为了解决这些问题,我们提出了一种安全有效的基于群组的切换认证方案(SEGHAS),同时将其命名为改进的隐私感知切换认证(iPAHA)。它能够实现所有的安全机制,同时只需要较少通信和计算成本,能够快速切换,可以避免信令拥塞并防止LTE-A网络中M2M通信中的未授权用户接入。此外,通过使用Pro-Verif工具进行网络测试和针对恶意攻击的身份验证,最终,实验结果表明我们的方案在计算和信令开销方面是最合适的。

关键词：安全快速切换 M2M LTE-A 隐私性

Research on Robust Watermarking Method of Digital Image Using SURF and DCT

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Research on Robust Watermarking Method of Digital Image Usin...

作者： Nawaz saqib ali 海南大学

学位级别：硕士

在计算机网络技术、多媒体技术和信息技术的不断发展中,数字化已成为显示信息的主要手段。从而促进了数字多媒体信息的存储,复制和传播。在这种情况下,对数字图像,音乐等的任意编辑,复制,修改和传播没有任何限制,这会导致各种社会问题,... 详细信息

在计算机网络技术、多媒体技术和信息技术的不断发展中,数字化已成为显示信息的主要手段。从而促进了数字多媒体信息的存储,复制和传播。在这种情况下,对数字图像,音乐等的任意编辑,复制,修改和传播没有任何限制,这会导致各种社会问题,例如信息安全,版权纠纷和盗版。随着网络和多媒体的发展,数字水印技术作为一种有效的版权保护方法已受到关注。使用基于图像特征的算法来提高数字水印算法的抗几何攻击能力已受到广泛关注。水印图像的常见攻击可分为常规攻击和几何攻击。常规攻击主要包括高斯滤波,噪声攻击,图像压缩等。几何攻击主要包括旋转,缩放,平移和剪切等操作。数字水印算法的鲁棒性是重要的性能指标。当前的水印算法对几何攻击的抵抗力是一个难以解决的问题。这项研究使用水印技术,将水印信息与宿主图像的特征相关联。所研究的算法具有更好的鲁棒性,尤其是对几何攻击的抵抗力。主要研究内容如下:(1)研究了基于SURF感知哈希和DCT的鲁棒盲水印算法。该算法首先利用仿射变换与特征矩阵结合混沌加密技术对水印图像进行预处理,增强水印的机密性,对载体图像进行分块和DCT系数提取。通过修改DCT系数。完成水印的嵌入。并可以实现水印的盲提取。研究发现,SURF算法对几何攻击具有良好的鲁棒性,但是在感知哈希过程中需要优化特征模块的选择。(2)研究了基于SURF和DCT特征的鲁棒零水印算法,该算法也有助于双水印。首先,将原始图像从RGB空间转换为YUV空间,并提取亮度分量的SURF(加速鲁棒特征)。标记点,根据特征点的主要方向构造一个描述向量,实验结果表明,该算法有较好的鲁棒性。(3)研究了基于SURF和DCT和SVD的鲁棒水印算法。针对数字图像水印算法嵌入容量小,抗几何攻击性弱的问题,提出了一种基于加速鲁棒特征算法(SURF),冗余离散小波变换(RDWT)和奇异值分解(SVD)的数字水印算法。利用SURF算法的旋转不变性和平移不变性提取特征点,并对载波图像和水印图像进行RDWT和SVD变换以及逆变换,以实现水印的嵌入和提取。引入了随机采样一致性算法来优化特征点匹配结果。实验结果表明,该算法提高了嵌入水印的能力,有效提高了抗几何攻击的鲁棒性。

关键词：数字水印医学图像水印 SURF DCT

ChainApparel: A Trustworthy Blockchain and IoT-Based Traceability Framework for Apparel Industry 4.0

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Computers, Materials & Continua 2023年第11期77卷 1837-1854页

作者： Muhammad Shakeel Faridi saqib ali Guojun Wang Salman Afsar Awan Muhammad Zafar Iqbal Department of Computer Science University of AgricultureFaisalabad38000Pakistan School of Computer Science Guangzhou UniversityGuangzhou510006China Department of Mathematics and Statistics University of AgricultureFaisalabad38000Pakistan

Trustworthiness and product traceability are essential factors in the apparel industry 4.0 for establishing successful business relationships among stakeholders such as customers,manufacturers,suppliers,and *** stakeholder has implemented different technology-based systems to record and track product ***,these systems work in silos,and there is no intra-system communication,leading to a lack of complete supply chain traceability for all apparel ***,apparel stakeholders are reluctant to share their business information with business competitors;thus,they involve third-party auditors to ensure the quality of the final ***,the apparel manufacturing industry faces challenges with counterfeit products,making it difficult for consumers to determine the authenticity of the ***,in this paper,a trustworthy apparel product traceability framework called ChainApparel is developed using the Internet of Things(IoT)and blockchain to address these challenges of authenticity and traceability of apparel ***,multiple smart contracts are designed and developed for registration,process execution,audit,fault,and product traceability to authorize,validate,and trace every business transaction among the apparel ***,the real-time performance analysis of ChainApparel is carried out regarding transaction throughput and latency by deploying the compute nodes at different geographical locations using Hyperledger *** results conclude that ChainApparel accomplished significant performance under diverse workloads while ensuring complete traceability along the complex supply chain of the apparel ***,the ChainApparel framework helps make the apparel product more trustworthy and transparent in the market while safeguarding trust among the industry stakeholders.

关键词： Blockchain smart contracts hyperledger fabric Internet of Things traceability apparel industry 4.0

Mixed Attention Densely Residual Network for Single Image Super-Resolution

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Computer Systems Science & Engineering 2021年第10期39卷 133-146页

作者： Jingjun Zhou Jing Liu Jingbing Li Mengxing Huang Jieren Cheng Yen-Wei Chen Yingying Xu saqib ali Nawaz School of Information and Communication Engineering Hainan UniversityHaikou570228China State Key Laboratory of Marine Resource Utilization in the South China Sea Hainan UniversityHaikou570228China Research Center for Healthcare Data Science Zhejiang LabHangzhou311121China School of Computer Science and Cyberspace Security Hainan UniversityHaikou570228China Graduate School of Information Science and Engineering Ritsumeikan University5258577Japan College of Computer Science and Technology Zhejiang UniversityHangzhou311100China

Recent applications of convolutional neural networks(CNNs)in single image super-resolution(SISR)have achieved unprecedented ***,existing CNN-based SISR network structure design consider mostly only channel or spatial information,and cannot make full use of both channel and spatial information to improve SISR performance *** present work addresses this problem by proposing a mixed attention densely residual network architecture that can make full and simultaneous use of both channel and spatial ***,we propose a residual in dense network structure composed of dense connections between multiple dense residual groups to form a very deep *** structure allows each dense residual group to apply a local residual skip connection and enables the cascading of multiple residual blocks to reuse previous features.A mixed attention module is inserted into each dense residual group,to enable the algorithm to fuse channel attention with laplacian spatial attention effectively,and thereby more adaptively focus on valuable feature *** qualitative and quantitative results of extensive experiments have demonstrate that the proposed method has a comparable performance with other stateof-the-art methods.

关键词： Channel attention Laplacian spatial attention residual in dense mixed attention

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红细胞膜包覆PEI用于基因递送

红细胞膜包覆PEI用于基因递送

作者： Syed saqib ali Zaidi 天津大学

学位级别：硕士

随着细胞生物学和材料科学的发展,纳米粒子能够被精确制备和优化,从而得到性能优化的材料。特别是,细胞治疗受到越来越多的关注,因为它们能够在整个循环系统中运输各种物质;它们被装载到纳米粒子的表面或内部。细胞膜伪装纳米粒子是一... 详细信息

随着细胞生物学和材料科学的发展,纳米粒子能够被精确制备和优化,从而得到性能优化的材料。特别是,细胞治疗受到越来越多的关注,因为它们能够在整个循环系统中运输各种物质;它们被装载到纳米粒子的表面或内部。细胞膜伪装纳米粒子是一类新型的仿生纳米粒子,它结合了细胞膜的独特功能和合成纳米材料的多功能性,能够有效传递治疗药物。血细胞包括红细胞、白细胞和血小板已经广泛地用作药物载体,它们具有许多独特的优点,如循环时间长(尤其是红细胞),靶向释放能力(特别是血小板)和天然粘合剂性质(白细胞和血小板)。这些性能使得血细胞修饰递送系统以及基于细胞膜载体优于其他药物递送系统。本论文利用红细胞制备了红细胞囊泡,并合成了双硫键改性聚乙烯亚胺基因载体,并将红细胞囊泡通过静电相互作用,修饰聚乙烯亚胺载体,得到仿生基因递送系统。通过马尔文粒度仪对其粒径和电位进行了表征,并通过透射电镜对超声处理的红细胞进行了形貌表征,并用荧光标记表征了该基因载体递送系统的基因递送过程。

关键词：红细胞仿生纳米粒子基于细胞的疗法

采用扩压技术进行油田能量输入的水平轴风力机优化

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采用扩压技术进行油田能量输入的水平轴风力机优化

作者： saqib ali WAJID（萨奇）西安石油大学

学位级别：硕士

在可再生能源中,风能是使用最广泛的资源,因为它具有商业接受度、成本低、易于运行和维护、从概念到运行、创造新就业机会的时间相对较短、最少对环境的不利影响。风能行业的快速技术发展和多兆瓦级水平轴风力涡轮机的可用性进一步推动... 详细信息

在可再生能源中,风能是使用最广泛的资源,因为它具有商业接受度、成本低、易于运行和维护、从概念到运行、创造新就业机会的时间相对较短、最少对环境的不利影响。风能行业的快速技术发展和多兆瓦级水平轴风力涡轮机的可用性进一步推动了全球风电利用的推广。众所周知,风速随着高度的增加而增加,因此能量输出也随之增加。然而,由于结构和其他问题,不能超过一定的高度。因此,需要进行其他尝试来提高风力涡轮机的效率,将轮毂高度保持在可接受和可控的范围内。通过修改和重新设计叶片来降低切入速度和/或额定速度,可以提高风力涡轮机的效率或能量输出。这可以通过确定优化参数(例如年发电量、功率系数、能量成本、叶片质量和叶片设计约束(例如物理、几何和空气动力学))来解决。在我们的工作中,我们将添加一个护罩/增强器来包裹“裸涡轮”,从而将效率提高到4-5%,这可以作为最经济的输入能源。

关键词：可再生能源

SMS-Parking Service Introduced in Oman

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Computer Technology and Application 2011年第9期2卷 712-715页

作者： Syed Jafar Naqvi Hafedh AI-Shihi saqib ali Department of Information Systems College of Commerce and Economics Sultan Qaboos University Al-khod Oman

Mobile computing has increased quite rapidly over the past few years. The major drivers of mobile computing are large number of mobile phone users. As their number is increasing worldwide, different organizations are offering their services using the mobile devices. Oman is a developing country that strives to adapt M-services. The number of mobile phone users in Oman increased substantially since its launch in 1996. Prepaid mobile services and SMS （Short Message Services） were introduced in 2001 and both are currently popular with subscribers. Such fine appeal influenced many government organizations to go mobile with their services. This paper describes the SMS-Parking service, which is introduced recently by a joint venture of the Muscat Municipality and the Oman Mobile company offering mobile services to its citizens and reports the initial feedback of its users. This study shows that the new service is not yet popular among its users and may need their more positive attitudes toward it for its quick adoption.

关键词： Mobile computing m-services short message services (SMS) SMS-parking service