检索结果-南通市图书馆

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

多模式匹配算法

多模式匹配算法

作者： ahmed ABDO farhan SAIF 吉林大学

学位级别：硕士

大多数信息安全应用程序如反病毒程序以及入侵检测系统，都会选择多模式匹配算法作为其核心组成部分。该算法能够同时搜索千上万的模式串并且判断出这些模式串的位置。本文提出了两种多模式匹配算法，分别属于标准的多模式匹配算法和... 详细信息

大多数信息安全应用程序如反病毒程序以及入侵检测系统，都会选择多模式匹配算法作为其核心组成部分。该算法能够同时搜索千上万的模式串并且判断出这些模式串的位置。本文提出了两种多模式匹配算法，分别属于标准的多模式匹配算法和带有通配符的模式匹配算法。在标准方式下，多模式匹配算法的研究是基于哈希函数的。它对Karp-Rabin算法进行了扩展，其预处理时间为O(|P|)。如果没有匹配结果并且所有模式串长度相同，则算法执行时间为O(n+nlogk)。如果匹配后得到的模式串长度为l则验证函数需要时间l来检查是否真正匹配，其算法所用时间为O(n+nlogk+ooc(l))。如果模式串的长度不同则时间为O(mn+nk+ooc(l))(最会条件)，其中occ是真假匹配的数量。算法能够计算的最大的哈希值为xm(m+1)其中σ≈x/lnx。该算法不容易被攻击并且能够较好的运行在多处理器的并行模式下。此外本文提出的包含通配符的模式匹配算法是基于欧几里得距离和哈希函数的，该算法使用FFT来计算欧几里得距离和哈希函数。如果没有匹配结果，算法执行时间为O(k n logl)。如果匹配结果带有通配符并且通配符的符号仅存在于模式串中，需要时间为O(k n logl+ox)。如果文本中也包含了通配符，那么算法的执行时间要增加到O(k n log l+2ox)。对于匹配后的任意模式串，该算法存在1/σ的错误匹配率，其中k是模式串的数量，l为块长度，o是完成匹配的模式串的数量，x是完成匹配的模式串中块的数量。

关键词：多模式匹配 FFT 哈市函数欧几里得距离

Numerical Investigations of Flow Pattern and Anti-Vortex Measures of the Pumping Station Forebay

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Numerical Investigations of Flow Pattern and Anti-Vortex Mea...

作者： ahmed Nasr Elsayed Ali Nasr farhan 扬州大学

学位级别：硕士

泵站前池是外河和进水池（进水流道）的连接段,其作用是为了保证水流在从外河流向进水池（进水流道）的过程中能够平顺地扩散,为进水池（进水流道）提供良好的流态。依据水流方向,前池可分为正向进水前池和侧向进水前池两种基本类型,侧... 详细信息

泵站前池是外河和进水池（进水流道）的连接段,其作用是为了保证水流在从外河流向进水池（进水流道）的过程中能够平顺地扩散,为进水池（进水流道）提供良好的流态。依据水流方向,前池可分为正向进水前池和侧向进水前池两种基本类型,侧向进水前池拥有占的地方少、投资省等各种特点,在中国的农业灌溉、火电厂循环供水及城战给水排水泵站中较为常见,若泵站兴建所处地形条件狭窄、正向进水不容易布置的情况下常采用侧向进水前池,此时侧向进水前池的水流与进水池（进水流道）水流方向正交或斜交,因流向的改变,前池内易形成回流或旋涡,流速分布变得不均匀,流态紊乱,造成进水池（进水流道）入口处流速分布不均匀,将会导致泵装置水力效率从而降低,影响泵装置中安全稳定的运行,并缩短水泵的使用寿命。本论文以江苏省徐州市翟山大沟泵站为本次的研究对象,该泵站的前池为典型的侧向进水结构且前池具有较大纵向底坡,为明确该泵站侧向进水前池的流场分布特征并且能够确保机组安全稳定的运行,本文将使用数值模拟技术的方法对该泵站的侧向进水前池内流场进行数值模拟,通过定性和定量相结合的分析方法揭示前池的流场特征并对前池流态调控措施的流场调控效果进行对比和分析,优选整流措施,为实际工程提供技术支撑,也为同类型泵站的前池流态调控提供参考。目前,国内外一些学者针对泵站前池的流场及流态调控措施的研究展开了不少的研究工作,研究方法主要集中于数值模拟和物理模型试验。随着实际泵站工程规模越来越大且复杂,物理模型试验的研究方式越来越不经济,且具有耗时长、人力受限和所需场地大等诸多困难而在前池流场及流态调控研究中应用的较少,随着CFD（Computational Fluid Dynamic）技术的不断发展和成熟。通过中国知网以及其他等数据库的文献查询,采用数值模拟技术研究前池流场的论文占比89.33%,CFD数值模拟技术具有省时、省工及研究成本低的优点在前池流场及流态调控中的应用也变得越来越多,很多学者采用CFD数值模拟技术模拟实际泵站工程的运行以得出问题并分析解决,通过数值模拟结果提出了流态调控措施解决实际泵站前池中的流态问题,对实际工程的前池流场做出改善,同时和物理模型试验相比,CFD数值模拟技术可模拟更大范围的泵站建筑物并更快捷、更经济地获得结论,本文对泵站前池流场及流态调控措施的研究采用数值模拟技术。翟山大沟泵站主要承担暴雨季排除多余的降水,在旱季为了能够保证农作物的正常需水,属于农业灌排泵站。泵站有四个进水池,每个进水池都装有潜水轴流泵装置单机设计流量为4.25 m3/s,泵站总设计流量为17 m3/s,每台泵之间的间距为4.4 m,进水池的长度为9.8m。引河的研究尺寸为:长83.3m,宽11.2m。该泵站受限于实际地形条件布置,前池通过两个斜坡与进水池相连接,第一级斜坡高差为1.1 m,第二级斜坡高差为4.9 m。（一）研究内容及技术路线（1）采用数值模拟技术分析翟山大沟泵站的侧向进水前池的流场分布特征;（2）针对该侧向进水前池的流态特征,提出不同的整流措施并开展数值计算;（3）采用定量和定性相结合的方法对比分析各整流措施方案与初设方案的前池流场的差异性,选优合适的整流方案。本文采用Solidworks三维建模软件对翟山大沟泵站引河、前池、进水池和潜水泵进行流体域的整体三维建模,通过网格数量无关性和网格收敛性确定数值计算网格数量从而确保数值计算的有效性,在分析初设方案前池流场特征的基础上提出若干侧向进水前池的整流措施,并通过定量和定性相结合的方法对比分析各整流措施方案,最终优选合适的整流措施,本文所研究的技术路线如图1所示:图1技术路线图（二）数值计算方法基于对三维不可压缩流体的雷诺时均N-S方程和RNG k-ε湍流模型,RNG k-ε湍流模型计算式如式（1）所示,壁面函数采用可伸缩壁面函数处理近壁区流动,采用ANSYSCFX软件对翟山大沟泵站的引河、前池、进水池和潜水泵的流场进行整体数值求解。非结构化网格拥有着很强的自适应几何形体的优点,则引河、前池、进水池和潜水泵均使用非结构化网格剖分,针对流场分析的重点关注区域进行了局部网格加密处理。计算模型的进口边界条件设置为流量,出口边界条件设置为压力,固体壁面采用无滑移壁面处理,引河的平均粗糙度设置为2.5 mm,前池和进水池的壁面粗糙度设置为2 mm。引河、前池和进水池的表面为自由液面,忽略空气对水面产生的切应力和热交换采用对称平面条件,各相连过流建筑物的交界面均采用静静交界面。泵站前池数值计算各物理量的残差收敛精度设置为1×10-6。RANS可以如下进行:（1）k方程可以表示为:（2）ε方程可以定义为:（3）ε方程可以从RANS方程得到。涡流粘度为:μt=ρCμk2/ε（4）常数σκ,σε,C1,C2,＆Cμ是根据软件ANSYS-CFX中基于实验数据在5%

关键词：泵站前池流态数值模拟整流侧向进水

A Hybrid Duo-Deep Learning and Best Features Based Framework for Action Recognition

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第11期73卷 2555-2576页

作者： Muhammad Naeem Akbar farhan Riaz ahmed Bilal Awan Muhammad Attique Khan Usman Tariq Saad Rehman National University of Sciences and Technology(NUST) Islamabad46000Pakistan Department of Computer Science HITEC UniversityTaxilaPakistan College of Computer Engineering and Science Prince Sattam Bin Abdulaziz UniversityAl-Kharaj 11942Saudi Arabia

Human Action Recognition(HAR)is a current research topic in the field of computer vision that is based on an important application known as video *** in computer vision have introduced various intelligent methods based on deep learning and machine learning,but they still face many challenges such as similarity in various actions and redundant *** proposed a framework for accurate human action recognition(HAR)based on deep learning and an improved features optimization algorithm in this *** deep learning feature extraction to feature classification,the proposed framework includes several critical *** training fine-tuned deep learning models–MobileNet-V2 and Darknet53–the original video frames are *** feature extraction,pre-trained deep models are used,which are fused using the canonical correlation *** that,an improved particle swarm optimization(IPSO)-based algorithm is used to select the best *** that,the selected features were used to classify actions using various *** experimental process was performed on six publicly available datasets such as KTH,UT-Interaction,UCF Sports,Hollywood,IXMAS,and UCF YouTube,which attained an accuracy of 98.3%,98.9%,99.8%,99.6%,98.6%,and 100%,*** comparison with existing techniques,it is observed that the proposed framework achieved improved accuracy.

关键词： Action recognition deep learning features fusion features selection recognition

Multipartite symbioses in fungus-growing termites (Blattodea: Termitidae, Macrotermitinae) for the degradation of lignocellulose

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2021年第6期28卷 1512-1529页

作者： farhan Ahmad Gui-Ying Yang Shi-You Liang Qi-Huan Zhou Hassan ahmed Gaal Jian-Chu Mo Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insect Pests Institute of Insect SciencesCollege of Agricultural and BiotechnologyZhejiang UniversityHangzhouChina Entomology Section Central Cotton Research InstituteSakrandShaheed BenazirabadSindhPakistan Department of Entomology Faculty of Veterinary and Animal HusbandrySomali National UniversityMogadishuSomalia

Fungus-growing termites are among the most successful herbivorous animals and improve crop productivity and soil fertility.A range of symbiotic organisms can be found inside their ***,interactions of termites with these symbionts are poorly *** review provides detailed information on the role of multipartite symbioses(between termitophiles,termites,fungi,and bacteria)in fungus-growing termites for lignocellulose *** specific functions of each component in the symbiotic system are also *** on previous studies,we argue that the enzymatic contribution from the host,fungus,and bacteria greatly facilitates the decomposition of complex polysaccharide plant *** host-termitophile interaction protects the termite nest from natural enemies and maintains the stability of the microenvironment inside the colony.

关键词： bacteria enzyme activity lignocellulose degradation Macrotermitinae symbiosis Termitomyces

Big Model Strategy for Bridge Structural Health Monitoring Based on Data-Driven, Adaptive Method and Convolutional Neural Network (CNN) Group

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Structural Durability & Health Monitoring 2024年第6期18卷 763-783页

作者： Yadong Xu Weixing Hong Mohammad Noori Wael A.Altabey ahmed Silik Nabeel S.D.farhan Nanjing Highway Development Center Changzhou211106China Nanjing Zhixing Information Technology Co. Ltd.Nanjing210000China Department of Mechanical Engineering California Polytechnic State UniversitySan Luis ObispoCA 93405USA Department of Mechanical Engineering Faculty of EngineeringAlexandria UniversityAlexandria21544Egypt Department of Civil Engineering Nyala UniversityP.O.Box 155NyalaSudan School of Civil Engineering University of LeedsLeedsLS29JTUK

This study introduces an innovative“Big Model”strategy to enhance Bridge Structural Health Monitoring(SHM)using a Convolutional Neural Network(CNN),time-frequency analysis,and fine element *** ensemble methods,collaborative learning,and distributed computing,the approach effectively manages the complexity and scale of large-scale bridge *** CNN employs transfer learning,fine-tuning,and continuous monitoring to optimize models for adaptive and accurate structural health assessments,focusing on extracting meaningful features through time-frequency *** integrating Finite Element Analysis,time-frequency analysis,and CNNs,the strategy provides a comprehensive understanding of bridge *** diverse sensor data,sophisticated feature extraction,and advanced CNN architecture,the model is optimized through rigorous preprocessing and hyperparameter *** approach significantly enhances the ability to make accurate predictions,monitor structural health,and support proactive maintenance practices,thereby ensuring the safety and longevity of critical infrastructure.

关键词： Structural Health Monitoring(SHM) bridges big model Convolutional Neural Network(CNN) Finite Element Method(FEM)

Levels of antioxidant enzymes and alkaline protease from pulp and peel of sunflower

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2017年第6期7卷 533-537页

作者： Wesen Adel Mehdi Faridah Yusof Layla O.farhan Atheer Awad Mehde Raha ahmed Raus Department of Chemistry College of Sciences for WomenUniversity of Baghdad Department of Biotechnology Engineering College of EngineeringInternational Islamic University Malaysia Department of Technical Medical Analysis College of Health and Medical TechnologyMiddle Technical University

Objective:The activity of enzymes participating in the systems of antioxidant protection was assayed in the peel and pulp of *** essential roles of proteases in food stimulate research to find other sources of the enzyme especially from non-conventional *** the present work,we study several biochemical parameters in the pulp and peel of ***:Pulp and peel of sunflower was extracted,antioxidant enzymes and nonenzymatic antioxidant were *** protease was measured and purified from pulp in ***:High carbohydrate concentration,beta-carotene,catalase and ascorbate peroxidase activities,free radical scavenging capacity and free flavonoid content were observed in the peel of ***,MDA and ceruloplasmin activities were high in the pulp of ***:The present study concluded that peel in sunflower are strong radical scavengers and can be considered as good sources of natural antioxidants for medicinal and commercial *** analysis showed that protease activity was a significantly high in the pulp compared to the peel.

关键词： Pulp sunflower Antioxidant enzymes Free radical scavenging capacity Free flavonoid content Alkaline protease

Image Encryption Algorithm Based on New Fractional Beta Chaotic Maps

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2022年第7期132卷 119-131页

作者： Rabha W.Ibrahim Hayder Natiq ahmed Alkhayyat Alaa Kadhim farhan Nadia M.G.Al-Saidi Dumitru Baleanu Institute of Electrical and Electronics Engineers Kuala Lumpur59200Malaysia Information Technology College Imam Ja’afar Al-Sadiq UniversityBaghdad10001Iraq Department of Computer Technical Engineering College of Technical EngineeringIslamic UniversityNajaf192122Iraq Department of Computer Sciences University of TechnologyBaghdad10066Iraq Department of Applied Sciences University of TechnologyBaghdad10066Iraq Department of Mathematics Cankaya UniversityBalgatAnkara06530Turkey Institute of Space Sciences Magurele-BucharestR76900Romania Department of Medical Research China Medical UniversityTaichung40402Taiwan

In this study,a new algorithm of fractional beta chaotic maps is proposed to generate chaotic sequences for image *** proposed technique generates multi random sequences by shuffling the image pixel *** technique is used to blur the pixels connecting the input and encrypted images and to increase the attack *** proposed algorithm makes the encryption process sophisticated by using fractional chaotic maps,which hold the properties of *** fractional beta sequences are utilized to alter the image pixels to decryption *** experimental results proved that the proposed image encryption algorithm successfully encrypted and decrypted the images with the same *** output findings indicate that our proposed algorithm has good entropy and low correlation *** translates to enhanced security against different attacks.A MATLAB programming tool was used to implement and assess the image quality measures.A comparison with other image encryption techniques regarding the visual inspection and signal-to-noise ratio is provided.

关键词： Fractional calculus fractional beta function chaotic function image encryption

Virtual orthopedic assessment:Main principles and specific regions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Orthopedics 2021年第9期12卷 672-684页

作者： Khaled M Emara Ramy ahmed Diab Mohamed Amr Shady Abdelghaffar Mahmoud Mohamed Nour ahmed Abdelsalam Mahmoud ahmed Elshobaky Mona farhan Mostafa Gemeah ahmed K Emara Orthopedic Surgery Department Ain Shams UniversityCairo 11566Egypt Orthopedic Surgery Department Bank Ahly HospitalCairo 11566Egypt Department of Health Care Innovation Arizona State UniversityArizonaAZ 85287United States Department of Orthopedic Surgery Cleveland ClinicOhioNY 44195United States

Telemedicine was originally created as a way to treat patients who were located in remote places far away from local health facilities or in areas with shortages of medical *** is still used today to address those problems,and is increasingly becoming a tool for convenient medical *** the emergence of pandemics,telemedicine became almost a mandatory and valuable option for continuing to provide medical care in various *** the threat of pandemic progress has continued for months and may continue for years,it is essential to validate existing tools to maintain clinical assessment and patient treatment to avoid negative consequences of the lack of medical ***,the establishment of a virtual assessment technique that can be conducted effectively is of outmost importance as a way of adapting to the current *** study evaluated the role of telemedicine in the assessment of various orthopedic pathologies by means of a systematic virtual evaluation.

关键词： Telemedicine Virtual assessment Orthopedics Epidemic diseases

The impact on alpha emission rates of varying distances between a CR-39 detector and alpha-emitting bone samples

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Radiation Detection Technology and Methods 2021年第4期5卷 618-626页

作者： Nada farhan Kadhim Yasser Ayad Kadhim Rasha S.ahmed Ali A.Ridha Mostafa Y.A.Mostafa Department of Physics College of ScienceMustansiriyah UniversityBaghdadIraq Department of Physiology College of MedicineAl-Nahrain UniversityP.O.Box 70010AlkadhimiyaBaghdadIraq Physics Unit Science DepartmentRustaq College of EducationUniversity of Technology and Applied SciencesMuscatSultanate of Oman Physics Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt Ural Federal University Mira Street 19YekaterinburgRussia620002

Background Changing the distance between a sample and an exposed solid-state nuclear track detector affects the number of alpha tracks recorded by the *** concept had been used to distinguish high-energy alpha particles by computing the alpha emission rate at two distances(0 and 2 cm)from animal bone *** and methods Two Cr-39 detectors were placed in a container with bone ash inside to measure the alpha emission rate when the detectors were in contact with the ash and hung at a distance of 2 cm from the *** The alpha emission rate was found to be 62.7×10^(−4) Bq cm^(−2) when the detector was in contact with the sample(a small exposure area)and 324.4×10^(−4) Bq cm^(−2) when the sample was placed 2 cm away(a larger exposure area).A mathematical equalization of the exposure areas was conducted(the area of the detector exposed to the alpha emitter sample at a distance of 2 cm was equalized to the area exposed when in contact with the sample).After equalization,a reduction in the average value of the alpha emission rate from 324.4×10^(−4) to 17.4×10^(−4) Bq cm^(−2) was *** The increase in distance between the sample and the detector allowed only high-energy alpha particles with a range greater than the traveled distance to reach the ***,this system can distinguish the type and number of nuclides in the sample by changing the distance between the detector and the sample according to each nucleus ***,the results show that the alpha emission rates in these bone samples are higher than the local values.

关键词： Radioactivity Animal bone CR-39 detector Track density Alpha range