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Privacy Preservation in IoT Devices by Detecting Obfuscated Malware Using Wide Residual Network
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作者 Deema Alsekait Mohammed Zakariah +2 位作者 Syed Umar Amin Zafar Iqbal Khan Jehad Saad Alqurni 《Computers, Materials & Continua》 SCIE EI 2024年第11期2395-2436,共42页
The widespread adoption of Internet of Things(IoT)devices has resulted in notable progress in different fields,improving operational effectiveness while also raising concerns about privacy due to their vulnerability t... The widespread adoption of Internet of Things(IoT)devices has resulted in notable progress in different fields,improving operational effectiveness while also raising concerns about privacy due to their vulnerability to virus attacks.Further,the study suggests using an advanced approach that utilizes machine learning,specifically the Wide Residual Network(WRN),to identify hidden malware in IoT systems.The research intends to improve privacy protection by accurately identifying malicious software that undermines the security of IoT devices,using the MalMemAnalysis dataset.Moreover,thorough experimentation provides evidence for the effectiveness of the WRN-based strategy,resulting in exceptional performance measures such as accuracy,precision,F1-score,and recall.The study of the test data demonstrates highly impressive results,with a multiclass accuracy surpassing 99.97%and a binary class accuracy beyond 99.98%.The results emphasize the strength and dependability of using advanced deep learning methods such as WRN for identifying hidden malware risks in IoT environments.Furthermore,a comparison examination with the current body of literature emphasizes the originality and efficacy of the suggested methodology.This research builds upon previous studies that have investigated several machine learning methods for detecting malware on IoT devices.However,it distinguishes itself by showcasing exceptional performance metrics and validating its findings through thorough experimentation with real-world datasets.Utilizing WRN offers benefits in managing the intricacies of malware detection,emphasizing its capacity to enhance the security of IoT ecosystems.To summarize,this work proposes an effective way to address privacy concerns on IoT devices by utilizing advanced machine learning methods.The research provides useful insights into the changing landscape of IoT cybersecurity by emphasizing methodological rigor and conducting comparative performance analysis.Future research could focus on enhancing the recommended approach by adding more datasets and leveraging real-time monitoring capabilities to strengthen IoT devices’defenses against new cybersecurity threats. 展开更多
关键词 Obfuscated malware detection IoT devices Wide residual Network(WRN) malware detection machine learning
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Double balloon device compared to oxytocin for induction of labour after previous caesarean section 被引量:8
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作者 Estefanía Rodríguez Ferradas Izaskun Lasa Alvarado +2 位作者 Miren Arrue Gabilondo Irene Diez-Itza José García-Adanez 《Open Journal of Obstetrics and Gynecology》 2013年第1期212-216,共5页
Objective: To assess cervical changes, duration of oxytocin infusion, mode of delivery and complications after cervical ripening using a double balloon device in women with a previous caesarean section. Methods: Longi... Objective: To assess cervical changes, duration of oxytocin infusion, mode of delivery and complications after cervical ripening using a double balloon device in women with a previous caesarean section. Methods: Longitudinal study including 80 women with a previous caesarean section, no previous vaginal delivery and an unfavourable cervix (Bishop 展开更多
关键词 double Balloon device Induction Labor VAGINAL Birth AFTER CAESAREAN Cervical RIPENING
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Layered double hydroxides as electrode materials for flexible energy storage devices 被引量:2
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作者 Qifeng Lin Lili Wang 《Journal of Semiconductors》 EI CAS CSCD 2023年第4期30-45,共16页
To prevent and mitigate environmental degradation,high-performance and cost-effective electrochemical flexible energy storage systems need to be urgently developed.This demand has led to an increase in research on ele... To prevent and mitigate environmental degradation,high-performance and cost-effective electrochemical flexible energy storage systems need to be urgently developed.This demand has led to an increase in research on electrode materials for high-capacity flexible supercapacitors and secondary batteries,which have greatly aided the development of contemporary digital communications and electric vehicles.The use of layered double hydroxides(LDHs)as electrode materials has shown productive results over the last decade,owing to their easy production,versatile composition,low cost,and excellent physicochemical features.This review highlights the distinctive 2D sheet-like structures and electrochemical characteristics of LDH materials,as well as current developments in their fabrication strategies for expanding the application scope of LDHs as electrode materials for flexible supercapacitors and alkali metal(Li,Na,K)ion batteries. 展开更多
关键词 layered double hydroxide flexible energy storage devices structural designs electrochemical performances
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Double Intervention in Single Sitting: Percutaneous Device Closure and Permanent Pacemaker Implantation in a Patient with Atrial Septal Defect
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作者 Raghu Cherukupalli Shawkat Miro +3 位作者 Srinivas Movva Prashant Patil Nirlep Gajiwala Ashok Thakkar 《International Journal of Clinical Medicine》 2014年第20期1311-1315,共5页
Context: Atrial septal defect may rarely be associated with other cardiac diseases such as arrhythmia, and may require additional intervention. Case report: A 16-year-old boy presented with effort dyspnea, tiredness, ... Context: Atrial septal defect may rarely be associated with other cardiac diseases such as arrhythmia, and may require additional intervention. Case report: A 16-year-old boy presented with effort dyspnea, tiredness, and fatigue. The electrocardiograph revealed right bundle branch block, atrioventricular block, and left axis deviation. Ostium secundum type of atrial septal defect was detected by transthoracic echocardiography and was confirmed by transesophageal echocardiography. The patient was advised to undergo percutaneous device closure. Permanent pacemaker implantation was also suggested considering the risk of fatal arrhythmias associated with atrioventricular block. Consequently, patient underwent percutaneous atrial septal defect closure and implantation of pacemaker in a single sitting. Both the procedures were successful, after which the patient showed remarkable symptomatic improvement. Conclusion: In atrial septal defect patients with unexplained atrioventricular block, closure of atrial septal defect and implantation of pacemaker in single sitting appear to be an attractive modality. 展开更多
关键词 Atrial SEPTAL Defect Ostium Secundum Pacemaker PERCUTANEOUS device Closure double INTERVENTION in SINGLE SITTING
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Dependence of Plasma Parameters on Plate Separation and Filament Location in a Double Plasma Device
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作者 Monojit Chakraborty Bidyut Kumar Das +1 位作者 Mrinal Kumar Mishra Mainak Bandyopadhyay 《Journal of Modern Physics》 2012年第9期1002-1008,共7页
A pair of stainless steel (ss) plates separates the source and target regions of a double plasma device. Two sets of tungsten filaments, placed at different distances from the ss plates, are then used to produce plasm... A pair of stainless steel (ss) plates separates the source and target regions of a double plasma device. Two sets of tungsten filaments, placed at different distances from the ss plates, are then used to produce plasma alternately and the plasma parameters in the source and target regions for different discharge voltage, discharge current and plate separation are measured using Langmuir probes. It is found that plasma density and electron temperature are considerably affected and respond differently to changes in the plate separations and the position of the filaments. 展开更多
关键词 FILAMENT LOCATION PLASMA Parameters double PLASMA device
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Effect of Single- versus Double-Layer Uterine Closure during Caesarean Section on Niche Formation and Menstrual Irregularity
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作者 Mohamed Samy Esraa Hussein Fouad Ghoneimy Walid Hitler 《Open Journal of Obstetrics and Gynecology》 2024年第1期57-68,共12页
Background: The myometrium at the location of the CS (caesarean section) scars, also known as residual myometrium thickness (RMT), is larger after a double-layer uterine closure procedure than following a single-layer... Background: The myometrium at the location of the CS (caesarean section) scars, also known as residual myometrium thickness (RMT), is larger after a double-layer uterine closure procedure than following a single-layer one. It may lessen the formation of a niche that is the myometrium’s disruption at the location of the scar of the uterus. Gynecological manifestations, obstetric problems in a future pregnancy and birth, and maybe subfertility are linked to thin RMT and a niche. Objective: To ascertain if double-layer unlocked closure of the uterus is better than single-layer one in terms of post-menstrual spotting and niche development following a first CS. Patients and Methods: In this randomized clinical study, 287 patients were evaluated for qualifying. Of all eligible individuals, 57 patients were excluded from the study based on the inclusion criteria. Results: The variation in ages, gestational age, body mass index (BMI), and cesarean section indications between the two assigned groups is statistically insignificant. However, postmenstrual spotting was statistically significantly more common in single-layer group compared to in double-group. The current study revealed ultrasound findings suggestive of niche formation was statistically significantly more common in single-layer group compared to in double-layer group. Conclusion: As evident from the current study, it demonstrates the advantages of double-layer unlocked closure of the uterus over single-layer one in terms of post-menstrual spotting and niche development following first-time cs. Thus, we deduced that fewer niches are formed, and fewer menstrual spotting occurs in the presence of double unlocked layers closure. To ascertain the impact of uterus closure method on post-operative niche development and the risk of obstetrics and gynaecological problems, further prospective trials with extended follow-up periods are required. 展开更多
关键词 SINGLE-LAYER double Caesarean Section residual Myometrium Thickness
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双粒竖直勺盘式花生精量穴播器节本增效优化设计与应用
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作者 吾斯曼·吾木尔 阿拉法特·买尔旦 +2 位作者 沙塔尔·司马义 克然木·热合木吐力 祖丽皮亚·艾合买提 《农机化研究》 北大核心 2025年第2期114-121,共8页
根据目前新疆地区花生双粒播种需求,针对现有穴播器结构复杂、维修困难及精量穴播合格率低等问题,通过单粒取种、双粒排种的方式,设计了一种双粒竖直勺盘式花生精量穴播器。通过阐述穴播器结构组成及工作原理,清晰阐明了花生从取种到投... 根据目前新疆地区花生双粒播种需求,针对现有穴播器结构复杂、维修困难及精量穴播合格率低等问题,通过单粒取种、双粒排种的方式,设计了一种双粒竖直勺盘式花生精量穴播器。通过阐述穴播器结构组成及工作原理,清晰阐明了花生从取种到投种整个工作过程,同时对穴播器关键部件取种盘和隔板的结构参数进行了设计。为验证穴播器结构尺寸及性能的可靠性,选取转速、取种窝眼宽度、开口角度为试验因素,以双粒率、漏播率、重播率为试验指标,进行三因素三水平正交试验,并运用Design-Expert软件进行试验分析及参数优化等,得出最优排种组合为转速26.04 r/min、取种窝眼宽度8.8 mm、开口角度52.96°。此时双粒率94.68%、漏播率2.85%、重播率2.47%,符合国家标准。 展开更多
关键词 穴播器 花生 勺盘式 双粒
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Treatment of gastrointestinal bleeding in left ventricular assist devices:A comprehensive review 被引量:2
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作者 Srikanth Vedachalam Gokulakrishnan Balasubramanian +1 位作者 Garrie J Haas Somashekar G Krishna 《World Journal of Gastroenterology》 SCIE CAS 2020年第20期2550-2558,共9页
Left ventricular assist devices(LVAD)are increasingly become common as life prolonging therapy in patients with advanced heart failure.Current devices are now used as definitive treatment in some patients given the im... Left ventricular assist devices(LVAD)are increasingly become common as life prolonging therapy in patients with advanced heart failure.Current devices are now used as definitive treatment in some patients given the improved durability of continuous flow pumps.Unfortunately,continuous flow LVADs are fraught with complications such as gastrointestinal(GI)bleeding that are primarily attributed to the formation of arteriovenous malformations.With frequent GI bleeding,antiplatelet and anticoagulation therapies are usually discontinued increasing the risk of life-threatening events.Small bowel bleeds account for 15%as the source and patients often undergo multiple endoscopic procedures.Treatment strategies include resuscitative measures and endoscopic therapies.Medical treatment is with octreotide.Novel treatment options include thalidomide,angiotensin converting enzyme inhibitors/angiotensinⅡreceptor blockers,estrogen-based hormonal therapies,doxycycline,desmopressin and bevacizumab.Current research has explored the mechanism of frequent GI bleeds in this population,including destruction of von Willebrand factor,upregulation of tissue factor,vascular endothelial growth factor,tumor necrosis factor-α,tumor growth factor-β,and angiopoetin-2,and downregulation of angiopoetin-1.In addition,healthcare resource utilization is only increasing in this patient population with higher admissions,readmissions,blood product utilization,and endoscopy.While some of the novel endoscopic and medical therapies for LVAD bleeds are still in their development stages,these tools will yet be crucial as the number of LVAD placements will likely only increase in the coming years. 展开更多
关键词 Left ventricular assist device Push enteroscopy double balloon enteroscopy Video capsule endoscopy OCTREOTIDE BEVACIZUMAB Gastrointestinal bleeding
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Fabrication of Fuze Micro-electro-mechanical System Safety Device 被引量:8
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作者 DU Liqun JIA Shengfang +1 位作者 NIE Weirong WANG Qijia 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第5期836-841,共6页
Fuze micro-electro-mechanical system(MEMS) has become a popular subject in recent years.Studies have been done for the application of MEMS-based fuze safety and arm devices.The existing researches mainly focused on ... Fuze micro-electro-mechanical system(MEMS) has become a popular subject in recent years.Studies have been done for the application of MEMS-based fuze safety and arm devices.The existing researches mainly focused on reducing the cost and volume of the fuze safety device.The reduction in volume allows more payload and,thus,makes small-caliber rounds more effective and the weapon system more affordable.At present,MEMS-based fuze safety devices are fabricated mainly by using deep reactive ion ething or LIGA technology,and the fabrication process research on the fuze MEMS safety device is in the exploring stage.In this paper,a new micro fabrication method of metal-based fuze MEMS safety device is presented based on ultra violet(UV)-LIGA technology.The method consists of SU-8 thick photoresist lithography process,micro electroforming process,no back plate growing process,and SU-8 photoresist sacrificial layer process.Three kinds of double-layer moveable metal devices have been fabricated on metal substrates directly with the method.Because UV-LIGA technology and no back plate growing technology are introduced,the production cycle is shortened and the cost is reduced.The smallest dimension of the devices is 40 μm,which meets the requirement of size.To evaluate the adhesion property between electroforming deposit layer and substrate qualitatively,the impact experiments have been done on the device samples.The experimental result shows that the samples are still in good condition and workable after undergoing impact pulses with 20 kg peak and 150 μs duration and completely met the requirement of strength.The presented fabrication method provides a new option for the development of MEMS fuze and is helpful for the fabrication of similar kinds of micro devices. 展开更多
关键词 fuze MEMS safety device UV-LIGA technology double-layer moveable device micro electroforming
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Technical Note and Brief Overview of the Materials Science and Technology along with Designing Aspects for Development of Spintronic Devices with Optimum Efficiency 被引量:1
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作者 Ritu Walia Kamal Nain Chopra 《Journal of Materials Science and Chemical Engineering》 2020年第4期98-105,共8页
One of the major challenges in designing and fabricating Spintronic devices is the choice of both, Materials and the Technology, along with understanding the intricacies of the Designing aspects. In this communication... One of the major challenges in designing and fabricating Spintronic devices is the choice of both, Materials and the Technology, along with understanding the intricacies of the Designing aspects. In this communication, we have attempted to briefly discuss these factors, with an aim to draw the attention of the Materials Scientists and Technologists to this serious challenge, in the direction of which, though a lot of research and development work has been done, still needs more concerted efforts to be made in order to make the Spintronic devices that can offer good efficiency for maximizing their usefulness. 展开更多
关键词 MATERIALS Science Technology and DESIGNING ASPECTS of SPINTRONIC devices Epitaxial growth double Ion Beam Sputtering Technique Magnetic Tunnel JUNCTIONS Giant Magneto Resistance
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Current status of device-assisted enteroscopy: Technical matters, indication, limits and complications 被引量:5
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作者 Riccioni Maria Elena Urgesi Riccardo +3 位作者 Cianci Rossella Alessandra Bizzotto Galasso Domenico Costamagna Guido 《World Journal of Gastrointestinal Endoscopy》 CAS 2012年第10期453-461,共9页
Enteroscopy, defined as direct visualization of the smallbowel with the use of a fiberoptic or capsule endoscopy, has progressed considerably over the past severalyears. The need for endoscopic access to improvediagno... Enteroscopy, defined as direct visualization of the smallbowel with the use of a fiberoptic or capsule endoscopy, has progressed considerably over the past severalyears. The need for endoscopic access to improvediagnosis and treatment of small bowel disease hasled to the development of novel technologies one ofwhich is noninvasive, the video capsule, and a type of invasive technique, the deviceassisted enteroscopy.In particular, the device-assisted enteroscopy consiststhen of three different types of instruments all able toallow, in skilled hands, to display partially or throug-hout its extension (if necessary) the small intestine.Newer devices, double balloon, single balloon and spiral endoscopy, are just entering clinical use. The aim of this article is to review recent advances in small bowelenteroscopy, focusing on indications, modifications toimprove imaging and techniques, pitfalls, and clinical applications of the new instruments. With new technologies, the trials and tribulations of learning new endo-scopic skills and determining their role in the diagnosisand treatment of small bowel disease come. Identification of small bowel lesions has dramatically improved.Studies are underway to determine the best strategy toapply new enteroscopy technologies for the diagnosisand management of small bowel disease, particularly obscure bleeding. Vascular malformations such as angiectasis and small bowel neoplasms as adenocar cinomaor gas trointestinal stromal tumors. Complete entero-scopy of the small bowel is now possible. However, because of the length of the small bowel, endoscopic examination and the rapeutic maneuvers require significant skill, radiological assistance, the use of deep sedation with the assistance of the anesthetist. Prospective ran-domized studies are needed to guide diagnostic testing and the rapy with these new endoscopic techniques. 展开更多
关键词 device-assisted ENTEROSCOPY double BALLOON Single BALLOON Spiral endoscopy
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Design of an Ultrafast Frequency Doubling Photonic Device
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作者 黄金哲 苏林 +2 位作者 浦绍质 孙上傲 张留洋 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期67-70,共4页
Ultrashort pulses complicate the frequency conversion in a nonlinear crystal, where group velocity mismatch becomes the main obstacle due to dispersion. We present a design for group velocity compensated second harmon... Ultrashort pulses complicate the frequency conversion in a nonlinear crystal, where group velocity mismatch becomes the main obstacle due to dispersion. We present a design for group velocity compensated second harmonic generation in a modulated nonlinear structure, embedded in a liquid crystal box. In this structure, nonlinear crystals act as sources of signal and liquid crystals compensate for group velocity mismatch originating from nonlinear crystals. There are the advantages of the flexible, controllable birefringence of liquid crystals. Meanwhile, a method calculating the parameters of this type of structure is presented. To make it clear, an example is provided. Furthermore, the structure can also be shaped as a waveguide to support integration into other optical devices, applicable to all-optical processing systems. 展开更多
关键词 of on BE is it Design of an Ultrafast Frequency Doubling Photonic device in for BBO
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Thermo-mechanical and Experimental Analysis of Double Pass Line Heating
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作者 Pankaj Biswas N. R. Mandal +1 位作者 O. P. Sha M. M. Mahapatra 《Journal of Marine Science and Application》 2011年第2期190-198,共9页
The present investigation deals with process analysis of oxy-acetylene flame assisted double pass line heating for varying plate thickness, oxy-acetylene flame as the heat source for multi pass line heating to achieve... The present investigation deals with process analysis of oxy-acetylene flame assisted double pass line heating for varying plate thickness, oxy-acetylene flame as the heat source for multi pass line heating to achieve 3-D bending of plates with varying thicknesses was studied. The oxy-acetylene flame was modeled as the moving heat source in the FEM analysis. The transient thermal histories were predicted taking into account the temperature dependent thermo-mechanical properties. A comparative study between single pass and double pass line heating residual deformation was also carried out. The temperature distribution and residual detbrmations predicted by the numerical model developed in the present work compared fairly well with those of the experimental ones. 展开更多
关键词 double pass thermal history residual defolxnations 3-D FEM transient analysis elasto-plastic analysis oxy-acetylene gas torch
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气吸双行错置式玉米密植精量排种器设计与试验 被引量:4
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作者 王韦韦 宋岚洲 +3 位作者 石文兵 魏德华 陈永新 陈黎卿 《农业机械学报》 EI CAS CSCD 北大核心 2024年第3期53-63,共11页
针对大豆-玉米复合密植播种模式下传统气吸式排种器单行种盘高转速作业导致充种时间短、气流稳定性差,难以实现高速精量密植播种的问题,设计了一种气吸双行错置式玉米密植精量排种器,阐述了排种器结构与工作原理,对其工作过程及关键部... 针对大豆-玉米复合密植播种模式下传统气吸式排种器单行种盘高转速作业导致充种时间短、气流稳定性差,难以实现高速精量密植播种的问题,设计了一种气吸双行错置式玉米密植精量排种器,阐述了排种器结构与工作原理,对其工作过程及关键部件进行理论分析,构建充种和投种环节的种子力学模型,确定排种盘内外环型孔排布、投种轮、气室等关键结构参数,并开展单、双气道内负压分布、型孔内气流场特性分析,基于DEM-CFD耦合方法对排种器的排种过程进行仿真分析,以作业速度、气室结构和负压为试验因素,充种合格指数、重充指数和漏充指数为评价指标,优选出最优气室结构。通过台架试验开展不同气吸式排种器排种性能对比试验。试验结果表明,在作业速度为5~10 km/h的高速密植工况下,气吸双行错置式密植精量排种器排种合格指数均大于88.7%,且作业速度为10 km/h时,相较于常用单圆环气吸式排种器合格指数提高5.5个百分点,漏播指数降低5.6个百分点;田间试验结果表明,在作业速度为5 km/h下,播种合格指数为95.7%,重播指数为1.6%,漏播指数为2.8%。提出的气吸双行错置式玉米密植精量排种器在高速作业时拥有良好的排种性能,能够满足大豆-玉米高速精量密植播种要求。 展开更多
关键词 玉米 双行错置式 气吸式排种器 DEM-CFD 气室结构
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车端侧滚减振装置对高速双层动车组动力学性能的影响分析 被引量:1
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作者 王昕 代亮成 +4 位作者 杨东晓 罗贇 池茂儒 郭兆团 曾鹏程 《中国机械工程》 EI CAS CSCD 北大核心 2024年第4期742-751,共10页
双层动车组设置较大的二系横向阻尼来抑制一次蛇行引起的共振,而较大的二系横向阻尼会使车辆的横向平稳性变差。针对某型高速双层动车组横向平稳性差的问题,基于车端侧滚减振装置的工作原理建立了车端侧滚减振装置在车体滚摆和摇头运动... 双层动车组设置较大的二系横向阻尼来抑制一次蛇行引起的共振,而较大的二系横向阻尼会使车辆的横向平稳性变差。针对某型高速双层动车组横向平稳性差的问题,基于车端侧滚减振装置的工作原理建立了车端侧滚减振装置在车体滚摆和摇头运动状态下的数学模型,并将AMEsim软件中建立的减振器仿真模型与台架试验进行验证。最后通过建立车端侧滚减振装置与被试车辆的联合仿真模型,在不改变车辆现有悬挂参数的基础上对车端侧滚减振装置的关键参数进行优化选取。仿真结果表明,车端侧滚减振装置可以在不影响车辆垂向平稳性、保证曲线运行安全性的前提下有效改善双层动车组的横向平稳性。 展开更多
关键词 高速双层动车组 车端侧滚减振装置 横向平稳性 参数优化
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多模态融合的三维目标检测方法研究
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作者 田枫 宗内丽 +5 位作者 刘芳 卢圆圆 刘超 姜文文 赵玲 韩玉祥 《计算机工程与应用》 CSCD 北大核心 2024年第13期113-123,共11页
针对点云稀疏性与无序性导致基于纯点云的检测算法容易出现远小目标漏检和误检的问题,提出一种融合图像特征与点云体素特征的多模态三维目标检测算法。在图像特征提取阶段,提出一种轻量级深度残差网络,减少图像特征通道数,使其与点云体... 针对点云稀疏性与无序性导致基于纯点云的检测算法容易出现远小目标漏检和误检的问题,提出一种融合图像特征与点云体素特征的多模态三维目标检测算法。在图像特征提取阶段,提出一种轻量级深度残差网络,减少图像特征通道数,使其与点云体素特征相一致,提高点云和图像特征的融合能力;在体素特征与图像特征融合阶段,提出一种双次特征融合网络,在保留原始体素特征结构信息的基础上将图像特征和体素特征进行融合,使点云具备丰富的语义信息,提高远小目标检测精度。在KITTI数据集上实验结果显示,与基线模型相比,对小汽车、骑行者与行人的3D平均检测精度分别提高了0.76个百分点、2.30个百分点、3.43个百分点。实验结果验证了所提方法对于解决远小目标误检和漏检问题的有效性。 展开更多
关键词 三维目标检测 深度残差网络 体素特征 图像特征 特征融合 双次特征融合网络
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“光储直柔”建筑配电系统应用研究 被引量:4
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作者 容浩 《建筑电气》 2024年第3期33-38,4,共7页
以某项目为例分析“光储直柔”在建筑物中的应用,并对“光储直柔”系统的应用场景、建筑直流配电系统的关注点及“光储直柔”系统关键设备进行阐述。
关键词 光储直柔 低压直流配电 应用场景 配电电压 接地方式 保护与控制 电力电子变压器 直流剩余电流保护装置
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高速精量播种机阿基米德螺线型弧面双齿盘覆土装置设计与试验
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作者 刘芳 高筱钧 +2 位作者 贾宪 黄玉祥 张崇勤 《农业机械学报》 EI CAS CSCD 北大核心 2024年第6期91-100,120,共11页
针对现有重型精量播种机在高速作业时存在覆土装置影响播种均匀性、种沟内种子被“架空”等问题,基于阿基米德螺线切刃曲线与挤压式覆土原理相结合的思路,设计了一种阿基米德螺线型弧面双齿盘覆土装置,实现了覆土厚度适宜且均匀一致,降... 针对现有重型精量播种机在高速作业时存在覆土装置影响播种均匀性、种沟内种子被“架空”等问题,基于阿基米德螺线切刃曲线与挤压式覆土原理相结合的思路,设计了一种阿基米德螺线型弧面双齿盘覆土装置,实现了覆土厚度适宜且均匀一致,降低覆土作业对播种均匀性影响的目的。本研究对覆土装置的结构参数、覆土量进行分析,确定了影响覆土效果的主要参数取值范围;利用EDEM离散元仿真技术建立了覆土装置-种子-土壤间的离散元模型,对关键参数进行仿真优化,确定弧面双齿盘的最优参数组合;通过田间试验对该装置的作业性能进行了验证。研究结果表明:影响弧面双齿盘作业性能的主要结构参数为阿基米德螺线型弧面双齿盘的中心间距、安装倾角、入土深度。当弧面双齿盘的中心间距为142.6mm、安装倾角为20°、入土深度为55mm时,该装置通过性能良好,覆土厚度均匀一致,平均厚度为47mm,合格粒距标准差、变异系数与空白对照组分别相差0.22mm、1.81个百分点,对播种均匀性影响小,满足精量播种的农艺要求。 展开更多
关键词 精量播种机 覆土装置 阿基米德螺线型 弧面双齿盘
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磁脱扣器动作响应分析及储能电容匹配设计
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作者 李奎 佟盟 +3 位作者 武一 卢志伟 胡博凯 徐子健 《电力自动化设备》 EI CSCD 北大核心 2024年第1期167-173,共7页
驱动电路与磁脱扣器是电磁式漏电保护器的核心组件,磁脱扣器需与储能电容匹配。在电磁式漏电保护器基本工作原理分析的基础上,建立磁脱扣器的数学模型与有限元计算模型,根据激磁安匝变化进行衔铁响应状态分析,仿真不同线圈激励形式下磁... 驱动电路与磁脱扣器是电磁式漏电保护器的核心组件,磁脱扣器需与储能电容匹配。在电磁式漏电保护器基本工作原理分析的基础上,建立磁脱扣器的数学模型与有限元计算模型,根据激磁安匝变化进行衔铁响应状态分析,仿真不同线圈激励形式下磁脱扣器动作响应状态。研究衔铁角动量与角位移变化特征,根据无激励时衔铁释放临界角动量与角位移关系,确定不同线圈激励形式下的衔铁临界释放条件。研究电容电压激励源下衔铁所受力矩冲量的变化规律,分析电容及其储能对衔铁释放响应状态的影响,根据临界储能最小的原则确定电容匹配,可以降低衔铁可靠释放所需储能。通过对磁脱扣器样机进行实验测试,验证了理论分析与仿真计算的正确性。 展开更多
关键词 电磁式漏电保护器 磁脱扣器 临界释放条件 电容电压激励 储能电容匹配
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基于单片机控制的异形件双轨供料装置的设计
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作者 徐平凡 王文彬 +1 位作者 徐鸣利 黄健 《机电工程技术》 2024年第3期60-62,共3页
在电子电路板制造行业,部分非标异性元件需要人工完成供料工序,再对接快速贴片机(Surface Mount Technology,SMT)完成整个生产工序,效率低下,无法满足电子产品组装行业的发展需求。为此设计了一种基于单片机控制的散料异形件供料器,包括... 在电子电路板制造行业,部分非标异性元件需要人工完成供料工序,再对接快速贴片机(Surface Mount Technology,SMT)完成整个生产工序,效率低下,无法满足电子产品组装行业的发展需求。为此设计了一种基于单片机控制的散料异形件供料器,包括2套振动装置和直线导轨,振动装置呈螺旋形上升与直线轨道连接,2个直线导轨并行工作,直线振动器可使导轨部件振动使导槽内的散料移动,当散料移动至导槽的末端时,插件机吸夹嘴定点取料从而进行自动贴插件。与传统的手工贴插件相比,散料经本装置供料后,自动贴装品质更加得到保证。实践结果表明,该装置兼容现有的SMT设备及插件机设备,实现了供料器的全自动工作,提高了生产效率;所需员工从5人减少至1人,生产节拍从5 s/件降低至1 s/件,次品率从3‰大幅度下降至1‰。 展开更多
关键词 自动送料装置 双轨供料 SMT生产线 单片机控制
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