检索结果-南通市图书馆

Connected Components-based Colour Image Representations of Vibrations for a Two-stage Fault Diagnosis of Roller Bearings Using Convolutional Neural Networks

引用

Chinese Journal of Mechanical Engineering 2021年第3期34卷 73-93页

作者： hosameldin o.a.ahmed Asoke K Nandi Department of Electronic and Electrical Engineering Brunel University LondonUxbridge UB83PHUK School of Mechanical Engineering Xi’an Jiaotong UniversityXi’anChina

Roller bearing failure is one of the most common faults in rotating *** techniques for bearing fault diagnosis based on faults feature extraction have been *** feature extraction from fault signals requires expert prior information and human ***,deep learning algorithms have been applied extensively in the condition monitoring of rotating machines to learn features automatically from the input *** its robust performance in image recognition,the convolutional neural network(CNN)architecture has been widely used to learn automatically discriminative features from vibration images and classify health *** paper proposes and evaluates a two-stage method RGBVI-CNN for roller bearings fault *** first stage in the proposed method is to generate the RGB vibration images(RGBVIs)from the input vibration *** begin this process,first,the 1-D vibration signals were converted to 2-D grayscale vibration *** the conversion was completed,the regions of interest(RoI)were found in the converted 2-D grayscale vibration ***,to produce vibration images with more discriminative characteristics,an algorithm was applied to the 2-D grayscale vibration images to produce connected components-based RGB vibration images(RGBVIs)with sets of colours and texture *** the second stage,with these RGBVIs a CNN-based architecture was employed to learn automatically features from the RGBVIs and to classify bearing health *** cases of fault classification of rolling element bearings are used to validate the proposed *** results of this investigation demonstrate that RGBVI-CNN can generate advantageous health condition features from bearing vibration signals and classify the health conditions under different working loads with high ***,several classification models trained using RGBVI-CNN offered high performance in the testing results of the overall classification accura

关键词： Bearing fault diagnosis Image representation of vibrations Deep learning Convolutional neural networks

来源：

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

Nanosecond pulse and dual-wavelength Q-switched 1.5 μm fiber laser using MAX phase Cr2TiAlC2 saturable absorber

引用

optoelectronics Letters 2025年第1期21卷 7-12页

作者： ahmed Shakir AL-HITI Hiba HASSAN Department of Electrical Engineering Faculty of Engineering University of Anbar Department of Laser and optoelectronics Engineering University of Technology-Iraq

We demonstrated a new type of MAX phase material, chromium titanium aluminum carbide（Cr2TiAlC2） polymer film, to generate a passively Q-switched erbium-doped fiber laser（EDFL）. The film thickness was measured to be around 45 μm, which was fabricated using the embedding method with polyvinyl alcohol（PVA） polymer as hoster. The saturable absorber（SA） film demonstrates a dual-wavelength passively Q-switched EDFL which operates at 1 531 nm and 1 560.19 nm, respectively. The Q-switching pulse duration could be varied from 2.46 μs to 770 ns, while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increasing input pumping range from 154 mW to 300 mW. The maximum output power and pulse energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW, respectively.

关键词： Saturable absorbers

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Enhancing Solar Photovoltaic Efficiency:A Computational Fluid Dynamics Analysis

引用

Energy Engineering 2025年第1期122卷 153-166页

作者： Rahool Rai Fareed HussainMangi Kashif ahmed Sudhakar Kumaramsay Faculty of Mechanical and Automotive Engineering Universiti Malaysia Pahang Al-Sultan AbdullahPekan26600PahangMalaysia Faculty of Engineering Science&Technology Hamdard UniversityKarachi74600Pakistan Electrical Engineering Department SUKKUR IBA UniversitySukkur65200Pakistan Berlin School of Business and Innovation BSBI Faculty of Computer Science and InformaticsBerlin12043Germany Automotive Engineering Centre University Malaysia Pahang Al Sultan AbdullahPekan26600PahangMalaysia Centre for Research in Advanced Fluid&Processes(Fluid Centre) Universiti Malaysia Pahang Al-Sultan Abdullah(UMPSA)Paya BesarKuantan26300PahangMalaysia

The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable *** energy,among the various renewable sources,is particularly appealing due to its abundant ***,the efficiency of commercial solar photovoltaic(PV)modules is hindered by several factors,notably their conversion efficiency,which averages around 19%.This efficiency can further decline to 10%–16%due to temperature increases during peak sunlight *** study investigates the cooling of PV modules by applying water to their front surface through Computational fluid dynamics(CFD).The study aimed to determine the optimal conditions for cooling the PV module by analyzing the interplay between water film thickness,Reynolds number,and their effects on temperature reduction and heat *** CFD analysis revealed that the most effective cooling condition occurred with a 5 mm thick water film and a Reynolds number of *** specific parameters were found to maximize the heat transfer and temperature reduction *** finding is crucial for the development of practical and efficient cooling systems for PV modules,potentially leading to improved performance and longevity of solar *** cooling fluids or advanced cooling techniques that might offer even better efficiency or practical benefits.

关键词： PV module efficiency water film thickness reynolds number CFD analysis PV/T renewable energy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions

引用

Neural Regeneration Research 2025年第1期20卷 191-192页

作者： Narek Manukjan Daniel Fulton Zubair ahmed WMatthijs Blankesteijn Sébastien Foulquier Department of Pharmacology and Toxicology Maastricht UniversityMaastrichtThe Netherlands CARIM-School for Cardiovascular Diseases Maastricht UniversityMaastrichtThe Netherlands Neuroscience and ophthalmology Institute of Inflammation and AgeingUniversity of BirminghamEdgbastonBirminghamUK Centre for Trauma Sciences Research University of BirminghamEdgbastonBirminghamUK MHeNs-School for Mental Health and Neuroscience Maastricht UniversityMaastrichtThe Netherlands Department of Neurology Maastricht University Medical CenterMaastrichtThe Netherlands

As the population ages,the burden of age-related diseases becomes ***,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common ***,it is becoming clearer that underlying vascular pathology such as cerebral small vessel disease(cSVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of *** term cSVD refers to pathology affecting the small vessels of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CSVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018).

关键词： pathology becoming white

来源：

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

Review of Techniques for Integrating Security in Software Development Lifecycle

引用

Computers, Materials & Continua 2025年第1期82卷 139-172页

作者： Hassan Saeed Imran Shafi Jamil Ahmad Adnan ahmed Khan Tahir Khurshaid Imran Ashraf College of Electrical and Mechanical Engineering National University of Sciences and Technology(NUST)Rawalpindi46604Pakistan Department of Computer Science Abasyn University Islamabad CampusIslamabad45510Pakistan Military College of Signals National University of Sciences and Technology(NUST)Rawalpindi46600Pakistan Department of Electrical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

Software-related security aspects are a growing and legitimate concern,especially with 5G data available just at our *** conduct research in this field,periodic comparative analysis is needed with the new techniques coming up *** purpose of this study is to review the recent developments in the field of security integration in the software development lifecycle(SDLC)by analyzing the articles published in the last two decades and to propose a way *** review follows Kitchenham’s review *** review has been divided into three main stages including planning,execution,and *** the selected 100 articles,it becomes evident that need of a collaborative approach is necessary for addressing critical software security risks(CSSRs)through effective risk management/estimation *** risks using a numeric scale enables a comprehensive understanding of their severity,facilitating focused resource allocation and mitigation *** a comprehensive understanding of potential vulnerabilities and proactive mitigation efforts facilitated by protection poker,organizations can prioritize resources effectively to ensure the successful outcome of projects and initiatives in today’s dynamic threat *** review reveals that threat analysis and security testing are needed to develop automated tools for the *** estimation of effort required to prioritize potential security risks is a big challenge in software *** accuracy of effort estimation can be further improved by exploring new techniques,particularly those involving deep *** is also imperative to validate these effort estimation methods to ensure all potential security threats are *** challenge is selecting the right model for each specific security *** achieve a comprehensive evaluation,researchers should use well-known benchmark checklists.

关键词： Software development lifecycle systematic literature review critical software security risks national institute of standards and technology DevSecops open web application security project McGraw’s touch points

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems

引用

Structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： Sabrina Meddah Sid ahmed Tadjer Abdelhakim Idir Kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Efficiency of a Solar Green Building Using Bio-Sourced Materials for Indoor Temperature and Humidity optimization

引用

Energy Engineering 2025年第1期122卷 41-62页

作者： SoumiaMounir Youssef Maaloufa Abdelhamid Khabbazi ElinaMohd Husini Nurul SyalaAbdul Latip YakubuAminuDodo Rime ELHarrouni MinaAmazal Asma Souidi Malika Atigui ahmed Aharoune National School of Architecture Agadir New Complex Ibn ZohrAgadirBP 20732Morocco EMDD CERNE2DUniversity of Mohammed V in RabatEst SaleSaleBP 227Morocco Thermodynamics and Energetics Laboratory Faculty of ScienceIbn Zohr UniversityAgadirBP 8106Morocco Faculty of Built Environment University Sains Islam MalaysiaNilaiBP 71800Malaysia Architectural Engineering Department Najran UniversityNajranBP 1988Saudi Arabia The Centre of Scientific and Engineering Research Najran UniversityNajranBP 1988Saudi Arabia Euro-Mediterranean School of Architecture Design and UrbanismEuro-Mediterranean University of FezFezBP 51Morocco

A clean environment with low carbon emissions is the goal of research on the development of green and sustainable buildings that use bio-sourced materials in conjunction with solar energy to create more sustainable *** is particularly true in Africa,where there aren’t many studies on the *** current study suggests a 90 m^(2) model of a sustainable building in a dry climate that is movable to address the issue of housing in remote areas,ensures comfort in harsh weather conditions,uses solar renewable resources—which are plentiful in Africa—uses biosourced materials,and examines how these materials relate to temperature and humidity control while emitting minimal carbon *** order to solve the topic under consideration,the work is split into two sections:numerical and experimental *** TRNSYS and Revit,the suggested prototype building is examined numerically to examine the impact of orientation,envelope composition made of bio-sourced materials,and carbon *** a hygrothermal investigation,experiments are conducted to evaluate this prototype’s ***,an examination of the photovoltaic system’s production,consumption,and several scenarios used tomaximize battery life is included in the *** the biosourcedmaterial achieves a thermal transmittance of 0.15(W.m^(-2).K^(-1)),the results demonstrate an intriguing finding in terms of *** value satisfies the requirements of passive building,energy autonomy of the dwelling,and injection in-network with an annual value of 15,757 ***,compared to the literature,the heating needs ratio is 6.38(kWh/m^(2).an)and the cooling needs ratio is 49(kWh/m^(2).an),both of which are good *** to international norms,the inside temperature doesn’t go above 26℃,and the humidity level is within a comfortable range.

关键词： Bio-sourced materials energy sustainability green architecture built environment

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Endoscopic Assisted Eyebrow Craniotomy for Anterior Cranial Fossa Lesions: Clinical and Cosmetic outcomes

引用

open Journal of Modern Neurosurgery 2024年第1期14卷 30-47页

作者： ahmed hosameldin Hesham Elshetany Ehab Abdelhalim Department of Neurosurgery Faculty of Medicine Fayoum University Fayoum Egypt Department of Neurosurgery Faculty of Medicine Cairo University Cairo Egypt

Background: The eyebrow supraorbital keyhole approach could be considered a modified minimally invasive model for the classic pterional subfrontal approach in which an eyebrow incision and supraorbital mini craniotomy are performed for exposure of the anterior cranial fossa corridor. Methods: This study was retrospectively conducted on twenty four patients, age ranging from 20 to 65 years old, with anterior cranial fossa lesions who were meeting the eligibility criteria for eyebrow craniotomy in the period from August 2019 to January 2023. These patients were operated through eyebrow supraorbital approach in which microscopic endoscopic assisted technique were used. Extent of resection, clinical and cosmetic outcomes and complication incidence were assessed. Results: We included the twenty four patients who met inclusion criteria (17 females and 7 males) their ages ranged from 20 to 65 years. The most common pathology was meningioma in 19 patients. Two patients experienced supraorbital loss of sensation and only one patient experienced palsy of frontalis branch of facial nerve. Frontal sinus was breached in 3 patients with no patient experienced postoperative CSF leak. Total excision was accomplished for 23 patients. Four patients who had preoperative visual compromise, improvement of visual acuity and field defects was observed in 3 patients. No major intraoperative complications occurred. All patients filled cosmetic satisfaction questionnaire during their outpatient visits. For the eyebrow supraorbital approach, no incision related intolerable pain, no craniotomy defects or irregularities, no cosmetic complaints nor limitation of jaw opening were reported, and only minor symptoms in the form of limited eyebrow elevation, swelling and numbness in the forehead. Conclusions: The eyebrow craniotomy could be used safely as a more cosmetic and minimally invasive approach for a variety of anterior cranial fossa lesions. Endoscopic assistance has been found very useful f

关键词： Eyebrow Supraorbital Approach Keyhole Craniotomy Microscopic Endoscopic Minimally Invasive

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Multilevel Anterior Cervical Decompression and Fusion: Cervical Range of Motion and Clinical outcomes

引用

open Journal of Modern Neurosurgery 2022年第4期12卷 181-196页

作者： ahmed hosameldin Abdelrahman Senosi Mostafa Abdel-Latif Department of Neurosurgery Faculty of Medicine Fayoum University Fayoum Egypt

Background: Multiple level anterior cervical discectomy and fusion (ACDF) is indicated for those who suffer from multilevel stenosis or compression of the spinal canal. It was reported that this intervention would unfortunately lead to a loss of normal cervical range of motion (CRoM). Although, fewer studies have demonstrated the exact impact of the procedure on CRoM. In our study, short and midterm postoperative CRoM was described. Methods: Ninety patients who underwent ACDF were followed up postoperatively for at least 3 months. Active CRoM was measured in all patients preoperatively and in postoperative follow-ups by cervical spine X-rays in lateral dynamic view using Cobb’s angle method. Results: Unfortunately, postoperative CRoM was significantly diminished. At the short-term (3 months) follow-up there was a great limitation in CRoM. While an obvious increase in CRoM at the midterm (6 months) follow-up was observed in flexion especially. The reduction in global RoM (calculated as preoperative global RoM – 6 months postoperative RoM) was 4.1 and the reduction rate (calculated as reduction RoM divided by preoperative RoM) was 9.5%. The recovery RoM (calculated as 6 months postoperative RoM – 1 month postoperative RoM) was 8.2. The recovery rate (calculated as recovery RoM divided by 1 month postoperative RoM) was 26.5%. Conclusion: Active CRoM following multiple level ACDF was obviously diminished. The most affected motion after surgery was flexion. It was noticed that at the short-term follow-up CRoM would be more limited while after further follow up CRoM was obviously improved even in neck flexion motion.

关键词： Multilevel Anterior Cervical Discectomy Fusion Cervical Range of Motion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Percutaneous Fixation as an option for Traumatic Neurologically Intact Thoracolumbar Vertebral Fractures

引用

open Journal of Modern Neurosurgery 2024年第4期14卷 246-255页

作者： ahmed hosameldin Ashraf osman Mahmoud Gomaa Mahmoud Ramadan Department of Neurosurgery Fayoum University Faiyum Egypt Department of Neurosurgery Beni-Suef University Beni Suef Egypt

Background: The most frequent spinal fracture is the thoracolumbar fracture. Minimally invasive percutaneous fixation of cases having thoracolumbar vertebral fractures without neurological impairments has remained controversial. The advantages of minimally invasive percutaneous fixation are decreasing muscle and soft tissue injury, decreasing blood loss and infection rate, in addition to shortening hospital stay and recovery times. In comparison to the open technique, percutaneous fixation is adequate for treating thoracolumbar (TL) fractures without causing neurological impairments & with satisfactory outcomes in terms of kyphosis decline. Elevated radiation exposure to the surgeon &the patient, lack of decompression and fusion via bone graft, & a steep learning curve are all disadvantages of percutaneous fixation of vertebral fractures. Methods: This study was retrospectively conducted on forty-eight patients, age ranging from 16 to 65 years old, with a thoracolumbar (TL) fracture without causing neurological impairments who were meeting the eligibility criteria for fixation in the period from July 2019 to January 2024. Results: We included the forty-eight patients who met the inclusion criteria (34 males and 14 females) their ages ranged from 16 to 65 years. The most common pathology was L1 fracture in 38 patients. No major complications were experienced, only wound infection in five patients which was treated efficiently with repeated dressings and broad-spectrum antibiotics. Four patients experienced misdirected screws, only in one patient the screw encroach into the spinal canal with no deficit experienced, while the other three showed minimally laterally deviated screws. Conclusion: The advantages of percutaneous pedicle screw fixation in thoracolumbar fractures through preservation of posterior musculature, are less blood loss, shorter operative time, lower infection risk, less post-operative pain, shorter rehabilitation time as well as a shorter hospital st

关键词： Thoracolumbar Fractures Fracture Stability Percutaneous Fixation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：