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Intraoperative application of three-dimensional printed guides in total hip arthroplasty: A systematic review
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作者 Tim P Crone Bart M W Cornelissen +2 位作者 Jakob Van Oldenrijk Pieter Koen Bos Ewout S Veltman 《World Journal of Orthopedics》 2024年第7期660-667,共8页
BACKGROUND Acetabular component positioning in total hip arthroplasty(THA)is of key importance to ensure satisfactory post-operative outcomes and to minimize the risk of complications.The majority of acetabular compon... BACKGROUND Acetabular component positioning in total hip arthroplasty(THA)is of key importance to ensure satisfactory post-operative outcomes and to minimize the risk of complications.The majority of acetabular components are aligned freehand,without the use of navigation methods.Patient specific instruments(PSI)and three-dimensional(3D)printing of THA placement guides are increasingly used in primary THA to ensure optimal positioning.AIM To summarize the literature on 3D printing in THA and how they improve acetabular component alignment.METHODS PubMed was used to identify and access scientific studies reporting on different 3D printing methods used in THA.Eight studies with 236 hips in 228 patients were included.The studies could be divided into two main categories;3D printed models and 3D printed guides.RESULTS 3D printing in THA helped improve preoperative cup size planning and post-operative Harris hip scores between intervention and control groups(P=0.019,P=0.009).Otherwise,outcome measures were heterogeneous and thus difficult to compare.The overarching consensus between the studies is that the use of 3D guidance tools can assist in improving THA cup positioning and reduce the need for revision THA and the associated costs.CONCLUSION The implementation of 3D printing and PSI for primary THA can significantly improve the positioning accuracy of the acetabular cup component and reduce the number of complications caused by malpositioning. 展开更多
关键词 Total hip arthroplasty Three-dimensional printing Hip replacement surgery Three-dimensional planning Surgical guides
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Individualized treatment guided by endoscopic ultrasound-guided fine-needle aspiration for adrenocortical oncocytoma:A case report
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作者 Han Chen Xue Jing 《World Journal of Clinical Oncology》 2025年第2期158-164,共7页
BACKGROUND Adrenocortical oncocytoma is a rare,mostly benign,nonfunctional tumor that is typically detected incidentally.Its diagnosis is challenging because of the absence of distinctive imaging characteristics,neces... BACKGROUND Adrenocortical oncocytoma is a rare,mostly benign,nonfunctional tumor that is typically detected incidentally.Its diagnosis is challenging because of the absence of distinctive imaging characteristics,necessitating pathological validation.CASE SUMMARY We present a case report of a 35-year-old woman with an adrenal mass located on the left side,where endoscopic ultrasound-guided fine-needle aspiration(EUSFNA)was performed after comprehensive diagnostic assessment.Our results are consistent with those of previously documented cases regarding tumor demographics and anatomical location.Given the limited number of reports on this condition,long-term follow-up is crucial to enhance our understanding of its prognosis.CONCLUSION For patients with adrenocortical oncocytoma,EUS-FNA can enables collection of preoperative tissue specimens leading to suitable treatment strategies. 展开更多
关键词 Adrenocortical oncocytoma Non-functioning tumor Endoscopic ultrasound guided fine-needle aspiration Diagnosis Case report
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基于Guided BERTopic模型的产业链关键核心技术识别与发展趋势研判--以未来工业互联网为例
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作者 陈升 杨恒 张楠 《科学管理研究》 CSSCI 北大核心 2024年第3期35-44,共10页
产业链关键核心技术不仅是国之重器,而且对推动我国经济的高质量发展和保障国家安全起着至关重要的作用。当前,工业互联网产业链的关键技术发展成为我国的研究重点,该领域的重要性在2023年被提升至国家级重大研究计划。综合收集了1989-2... 产业链关键核心技术不仅是国之重器,而且对推动我国经济的高质量发展和保障国家安全起着至关重要的作用。当前,工业互联网产业链的关键技术发展成为我国的研究重点,该领域的重要性在2023年被提升至国家级重大研究计划。综合收集了1989-2024年中美两国在工业互联网领域的专利数据,基于《关键和新兴技术清单》和《未来工业互联网基础理论与关键技术重大研究计划》,构建了一套工业互联网产业链核心关键技术的种子词库。利用Guided BERTopic模型提取了产业链关键技术主题,并采用Logistic模型评估了这些技术的生命周期,进而对比中美两国的发展情况,提出了针对未来发展的建议。研究结果表明,相比美国,我国在大多数产业链核心技术方面仍处于成长阶段,而美国则已步入技术饱和阶段。展望未来,设备监测系统、设备管理系统、无线通信技术及能耗监测分析系统等被认为是具有巨大发展潜力的技术。研究提出了一种基于政策文件的产业链关键技术识别方法,并通过对工业互联网专利技术的实证分析,为制定相关政策提供了科学指导和建议。 展开更多
关键词 guided BERTopic模型 产业链核心关键技术 工业互联网 中美比较 专利文本 LOGISTIC模型
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Reducing risk of transjugular intrahepatic portosystemic shunt using ultrasound guided single needle pass 被引量:4
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作者 Sum Leong Hong Kuan Kok +1 位作者 Pradeep Govender William Torreggiani 《World Journal of Gastroenterology》 SCIE CAS 2013年第22期3528-3530,共3页
Delayed liver laceration following transjugular intrahepatic portosystemic shunt (TIPS) is a serious and likely underdiagnosed complication. It is however an important complication following TIPS, which remains one of... Delayed liver laceration following transjugular intrahepatic portosystemic shunt (TIPS) is a serious and likely underdiagnosed complication. It is however an important complication following TIPS, which remains one of the most technically challenging interventional procedures performed. In addition to laceration, a number of complications regarding bleeding and perforation are well described following TIPS procedures. We feel the adoption of techniques such as ours and that of other authors described in the literature using an ultrasoundguided percutaneous transhepatic approach with a small caliber needle provides a safer and less traumatic procedure and should reduce complications of bleeding and almost completely eliminate the risk of liver laceration. Our procedure was successfully performed under conscious sedation rather than general anaesthesia further reducing the overall procedural risk to the patient. 展开更多
关键词 Transjugular portal systemIC SHUNT Ultrasound guided HAEMORRHAGE COMPLICATION Reducing MORBIDITY Death Liver LACERATION
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Evaluation of axis alignment and refractive results of toric phakic IOL using image-guided system 被引量:4
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作者 Sherif Emerah 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第4期667-670,共4页
AIM: To evaluate accuracy of axis alignment and refractive results of toric phakic intraocular lens(IOL) implantation using a digital imaging system. METHODS: This retrospective study investigated toric implantable co... AIM: To evaluate accuracy of axis alignment and refractive results of toric phakic intraocular lens(IOL) implantation using a digital imaging system. METHODS: This retrospective study investigated toric implantable collamer lens(ICL) implantation in 30 eyes of 21 patients with myopic astigmatism more than 2.0 D guided with digital imaging system. Data were collected during the first week after phakic IOL implantation.RESULTS: Thirty eyes of 21 patients were included in our study. Patients includes 9 males and 12 females. The mean age of the patients was 26.5±7.1(range 21-44)y. The mean preoperative manifest astigmatism was 3.2±1.7(range from 2.25 to 4.75) D. The mean postoperative uncorrected distance visual acuity(UCDVA) were 0.07±0.07(range from 0.1 to 0.0) log MAR. The mean postoperative residual refractive cylinder was 0.25±0.29(range 0-0.75) D. Eyes with postoperative residual refractive cylinder of 0.5 D or less represented 80%(24 eyes). The mean postoperative toric IOL misalignment measured by the OPD scan III was 1.9°±1.45°(range from 0 to 5°). CONCLUSION: Image guided system allows accurate alignment of toric ICL. This is associated with good postoperative visual acuity and low residual refractive astigmatism which correlates with the precision of toric phakic IOL alignment. 展开更多
关键词 myopic ASTIGMATISM TORIC INTRAOCULAR lenses image guided system
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Simultaneous scheduling of machines and automated guided vehicles in flexible manufacturing systems using genetic algorithms 被引量:5
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作者 I.A.Chaudhry S.Mahmood M.Shami 《Journal of Central South University》 SCIE EI CAS 2011年第5期1473-1486,共14页
The problem of simultaneous scheduling of machines and vehicles in flexible manufacturing system (FMS) was addressed.A spreadsheet based genetic algorithm (GA) approach was presented to solve the problem.A domain inde... The problem of simultaneous scheduling of machines and vehicles in flexible manufacturing system (FMS) was addressed.A spreadsheet based genetic algorithm (GA) approach was presented to solve the problem.A domain independent general purpose GA was used,which was an add-in to the spreadsheet software.An adaptation of the propritary GA software was demonstrated to the problem of minimizing the total completion time or makespan for simultaneous scheduling of machines and vehicles in flexible manufacturing systems.Computational results are presented for a benchmark with 82 test problems,which have been constructed by other researchers.The achieved results are comparable to the previous approaches.The proposed approach can be also applied to other problems or objective functions without changing the GA routine or the spreadsheet model. 展开更多
关键词 automated guided vehicles (AGVs) SCHEDULING JOB-SHOP genetic algorithms flexible manufacturing system (FMS) SPREADSHEET
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Application of Automated Guided Vehicles in Smart Automated Warehouse Systems:A Survey 被引量:5
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作者 Zheng Zhang Juan Chen Qing Guo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1529-1563,共35页
Automated Guided Vehicles(AGVs)have been introduced into various applications,such as automated warehouse systems,flexible manufacturing systems,and container terminal systems.However,few publications have outlined pr... Automated Guided Vehicles(AGVs)have been introduced into various applications,such as automated warehouse systems,flexible manufacturing systems,and container terminal systems.However,few publications have outlined problems in need of attention in AGV applications comprehensively.In this paper,several key issues and essential models are presented.First,the advantages and disadvantages of centralized and decentralized AGVs systems were compared;second,warehouse layout and operation optimization were introduced,including some omitted areas,such as AGVs fleet size and electrical energy management;third,AGVs scheduling algorithms in chessboardlike environments were analyzed;fourth,the classical route-planning algorithms for single AGV and multiple AGVs were presented,and some Artificial Intelligence(AI)-based decision-making algorithms were reviewed.Furthermore,a novel idea for accelerating route planning by combining Reinforcement Learning(RL)andDijkstra’s algorithm was presented,and a novel idea of the multi-AGV route-planning method of combining dynamic programming and Monte-Carlo tree search was proposed to reduce the energy cost of systems. 展开更多
关键词 Automated guided vehicles(AGVs) smart automated warehouse systems AGVs scheduling AGVs route planning artificial intelligence(AI)
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Computational Analysis of Mixing Guide Vane Effects on Performance of the Supersonic Ejector-Diffuser System 被引量:2
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作者 Fan Shi Kong Heuy Dong Kim +1 位作者 Ying Zi Jin Toshiaki Setoguchi 《Open Journal of Fluid Dynamics》 2012年第3期45-55,共11页
The flow field in the ejector-diffuser system and its optimal operation condition are hardly complicated due to the complicated turbulent mixing, compressibility effects and even flow unsteadiness which are generated ... The flow field in the ejector-diffuser system and its optimal operation condition are hardly complicated due to the complicated turbulent mixing, compressibility effects and even flow unsteadiness which are generated inside the ejector- diffuser system. This paper aims at the improvement in ejector-diffuser system by focusing attention on entrainment ratio and pressure recovery. Several mixing guide vanes were installed at the inlet of the secondary stream for the purpose of the performance improvement of the ejector system. A Computational Fluid Dynamics (CFD) method based on Fluent has been applied to simulate the supersonic flows and shock waves inside the ejector. A finite volume scheme and density-based solver with coupled scheme were applied in the computational process. Standard k-ω turbulent model, implicit formulations were used considering the accuracy and stability. Previous experimental results showed that more flow vortexes were generated and more vertical flow was introduced into the stream under a mixing guide vane influence. Besides these effects on the secondary stream, the mixing guide vane effects on the shock system of the primary stream were also investigated in this paper. Optimal analysis results of the mixing guide vane effects were also carried out in detail in terms of the positions, lengths and numbers to achieve the best operation condition. The comparison of ejector performance with and without the mixing guide vane was obtained. The ejector-diffuser system performance is discussed in terms of the entrainment ratio, pressure recovery as well as total pressure loss. 展开更多
关键词 Ejector-Diffuser system MIXING guide VANE Shock Wave Compressible FLOW Supersonic FLOW
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Pipe Inspection System by Guide Wave Using a Long Distance Waveguide 被引量:2
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作者 Riichi Murayama Kenshi Matsumoto +1 位作者 Kenji Ushitani Makiko Makiko 《Modern Mechanical Engineering》 2015年第4期139-149,共11页
In the industrial fields, many high temperature structures that require a non-destructive inspection exist. However, there are currently few sensors that can carry out non-destructive testing in a high temperature env... In the industrial fields, many high temperature structures that require a non-destructive inspection exist. However, there are currently few sensors that can carry out non-destructive testing in a high temperature environment. In particular, the ultrasonic sensor is normally not used at over 50 degrees Celsius. Also, a special sensor for high temperature is currently available, but there are various constraints;it has not yet reached a level that is useful in industry. Therefore, we have been developing a new sensor system using a long waveguide which can transmit an ultrasonic wave from a long distance. Especially, this study focuses on applying the developed technique to a pipe which is used in a nuclear power plant. Therefore, the best rectangular-shaped waveguide was studied and attempted to be wound around a pipe to be driven by an acoustic source of a guide wave. Finally, the L (0, 2) and T (0, 1)-mode guide waves were successfully detected by optimizing the shape of the opposite edge of the rectangular-shaped waveguide that could detect the reflected signal from an artificial defect machined into a test pipe. 展开更多
关键词 WAVEguide guide WAVE EMAT NONDESTRUCTIVE Inspection PIPE
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Application of Automated Guided Vehicle (AGV) Based on Inductive Guidance for Newsprint Rolls Transportation System 被引量:1
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作者 陈超 王冰 叶庆泰 《Journal of Donghua University(English Edition)》 EI CAS 2004年第2期88-92,共5页
The paper presents the development and performance of a kinematics control scheme for the AGV based on inductive guidance in transporting newsprint rolls. The required error is pre-computed using a kinematics model of... The paper presents the development and performance of a kinematics control scheme for the AGV based on inductive guidance in transporting newsprint rolls. The required error is pre-computed using a kinematics model of the AGV taking into account the effect of various factors that contribute to improve tracking performance of the AGV. Simulation and experimental results illustrate that the kinematics model performs well and the results of various factors contribute to tracking performance of the AGV. 展开更多
关键词 Automated guided Vehicle Inductive guidance SIMULATION
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HYDRAULIC ACTIVE GUIDE ROLLER SYSTEM FOR HIGH-SPEED ELEVATOR BASED ON FUZZY CONTROLLER 被引量:1
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作者 FENG Yonghui ZHANG Jianwu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第5期68-73,共6页
Increase of elevator speed brings about amplified vibrations of high-speed elevator. In order to reduce the horizontal vibrations of high-speed elevator, a new type of hydraulic active guide roller system based on fuz... Increase of elevator speed brings about amplified vibrations of high-speed elevator. In order to reduce the horizontal vibrations of high-speed elevator, a new type of hydraulic active guide roller system based on fuzzy logic controller is developed. First the working principle of the hydraulic guide system is introduced, then the dynamic model of the horizontal vibrations for elevator cage with active guide roller system and the mathematical model of the hydraulic system are given. A fuzzy logic controller for the hydraulic system is designed to control the hydraulic actuator. To improve the control performance, preview compensation for the controller is provided. Finally, simulation and experiments are executed to verify the hydraulic active guide roller system and the control strategy. Both the simulation and experimental results indicate that the hydraulic active guide roller system can reduce the horizontal vibrations of the elevator effectively and has better effects than the passive one, and the fuzzy logic controller with preview compensation can give superior control performance. 展开更多
关键词 High-speed elevator Horizontal vibrations Hydraulic active guide roller system Fuzzy logic control
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Pipeline thickness estimation using the dispersion of higher-order SH guided waves 被引量:1
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作者 代政辰 刘金霞 +3 位作者 龙云飞 张建海 Tribikram Kundu 崔志文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期389-396,共8页
Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thi... Thickness measurement plays an important role in the monitoring of pipeline corrosion damage. However, the requirement for prior knowledge of the shear wave velocity in the pipeline material for popular ultrasonic thickness measurement limits its widespread application. This paper proposes a method that utilizes cylindrical shear horizontal(SH) guided waves to estimate pipeline thickness without prior knowledge of shear wave velocity. The inversion formulas are derived from the dispersion of higher-order modes with the high-frequency approximation. The waveform of the example problems is simulated using the real-axis integral method. The data points on the dispersion curves are processed in the frequency domain using the wave-number method. These extracted data are then substituted into the derived formulas. The results verify that employing higher-order SH guided waves for the evaluation of thickness and shear wave velocity yields less than1% error. This method can be applied to both metallic and non-metallic pipelines, thus opening new possibilities for health monitoring of pipeline structures. 展开更多
关键词 pipeline wall thickness higher-order modes SH guided waves DISPERSION
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Traveling Wave-Guide Channels of a New Coupled Integrable Dispersionless System
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作者 Abbagari Souleymanou Victor K.Kuetche +1 位作者 Thomas B.Bouetou Timoleon C.Kofane 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第1期10-14,共5页
In the wake of the recent investigation of new coupled integrable dispersionless equations by means of the Darboux transformation [Zhaqilao,et al.,Chin.Phys.B 18(2009) 1780],we carry out the initial value analysis of ... In the wake of the recent investigation of new coupled integrable dispersionless equations by means of the Darboux transformation [Zhaqilao,et al.,Chin.Phys.B 18(2009) 1780],we carry out the initial value analysis of the previous system using the fourth-order Runge-Kutta's computational scheme.As a result,while depicting its phase portraits accordingly,we show that the above dispersionless system actually supports two kinds of solutions amongst which the localized traveling wave-guide channels.In addition,paying particular interests to such localized structures,we construct the bilinear transformation of the current system from which scattering amongst the above waves can be deeply studied. 展开更多
关键词 dispersionaless equations Darboux transformation wave guide channels bilinear transformation
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Ultrasonic Inspection System Using a Long Waveguide with an Acoustic Horn for High-Temperature Structure
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作者 Riichi Murayama Masayuki Kobayashi +1 位作者 Kenshi Matsumoto Makiko Kobayashi 《Journal of Sensor Technology》 2014年第4期177-185,共9页
The nondestructive inspection of a high temperature structure is required in order to guarantee its safety. However, there are no useful sensors for high temperature structures. Some of them cannot work at temperature... The nondestructive inspection of a high temperature structure is required in order to guarantee its safety. However, there are no useful sensors for high temperature structures. Some of them cannot work at temperatures over 50°C. Another concern is that they are too expensive to use. A sensing system, which can transmit and receive an ultrasonic wave that travels a long distance using a long waveguide, has been studied. We confirmed that the optimal guided ultrasonic wave could travel more than 10 m using an electromagnetic transducer (EMAT) with a thin Ni-sheet surrounded on the surface of the bar and a 2-mm diameter bar as the waveguide. However, we had the difficult problem of receiving the reflected ultrasonic wave from the inside of a test specimen. We tried to improve the trial inspection system using an acoustic horn. An experiment in which the temperature of the test block was heated to about 500°C has now been completed. Finally, the condition of the bend in the waveguide to pass without reflection was confirmed. 展开更多
关键词 guide WAVE WAVEguide ACOUSTIC HORN NDI Thickness Measurement
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Rib and Groove Type Wind Guide Plate Analysis for Wind Power System
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作者 Chang Shiuh Ming 《Smart Grid and Renewable Energy》 2012年第4期334-337,共4页
This research is the analysis of rib and groove type wind guide plate for wind generation power system. This device generates electricity by the air flow producing by the high-speed vehicles driving on the road. It ca... This research is the analysis of rib and groove type wind guide plate for wind generation power system. This device generates electricity by the air flow producing by the high-speed vehicles driving on the road. It can produce electricity as long as there are car passing on the high way. The effect is much more efficient in heavy traffic with high speed. If we can set up a large number of this system along the highway, it can provide the lighting in the highway at night but also sell the extra electricity to the power companies with low cost, high performances and improvement of environmental benefits. 展开更多
关键词 RIB GROOVE WIND guide PLATE
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A New Guide Wave Inspection System Using Three Polarized Transverse Wave EMATs without Any Couplant
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作者 Riichi Murayama 《Journal of Sensor Technology》 2016年第4期110-121,共12页
A guide wave is provided with the characteristic of long range propagation in the axis direction of a pipe, so it is possible to detect many defects over a large pipe area at once. At present, there is a technique to ... A guide wave is provided with the characteristic of long range propagation in the axis direction of a pipe, so it is possible to detect many defects over a large pipe area at once. At present, there is a technique to generate a guide wave using a piezoelectric element (PZT). However, the transverse wave-transducer using PZT needs to require a high viscosity couplant because the transverse wave cannot travel into typical liquid like water or oil. A guide wave inspection system that uses an electromagnetic ultrasonic transducer (EMAT) which does not require any couplant has then been developed to solve this trouble. First, a guide wave into a pipe, L, T and F-mode, can be transmitted and received by a polarized shear horizontal transverse wave propagating to the thickness direction when the vibration direction has been adjusted to the best direction. At next stage, the three EMATs for L, T and F-mode with different polarized vibration directions were piled up to improve the performance at the same position under the permanent magnet to inspect the pipe at the same condition. Next, the system with the EMATs can be confirmed to be able to detect three guide wave modes signal with enough intensity. Finally, the detection performance using the test pipes with any artificial defects has been done by the developed pipe inspection system, and any drilled holes and any notches can be detected. It is indicated that the developed system could be useful in real industrial field. 展开更多
关键词 guide Wave Transverse Wave EMAT Nondestructive Inspection Pipe
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Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响
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作者 周晓英 袭玉荣 《中外医疗》 2024年第16期169-173,共5页
目的探讨分析Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响。方法简单随机选取2022年1月—2023年9月山东省泰安荣军医院收治的60例老年骨质疏松症患者为研究对象,按随机数表法将其分为常规组(实施常规护理干... 目的探讨分析Guided Care护理模式对老年骨质疏松症患者自我管理能力和生活质量的影响。方法简单随机选取2022年1月—2023年9月山东省泰安荣军医院收治的60例老年骨质疏松症患者为研究对象,按随机数表法将其分为常规组(实施常规护理干预),模式组(在常规组的基础上给予Guided Care护理模式干预),每组30例,两组均持续干预2个月,比较两组患者干预前后的健康认知水平、跌倒风险、自我管理能力、生活质量、护理满意度。结果干预2个月后,模式组的健康认知水平评分高于常规组,差异有统计学意义(P<0.05)。干预2个月后,模式组的跌倒风险评分低于常规组,差异有统计学意义(P<0.05)。干预2个月后,模式组的自我管理能力评分高于常规组,生活质量评分低于常规组,差异有统计学意义(P均<0.05)。干预2个月后,模式组的护理满意度为93.33%,高于常规组的护理满意度73.33%,差异有统计学意义(χ^(2)=4.320,P<0.05)。结论在老年骨质疏松症患者中,应用Guided Care护理模式,可以有效地提升患者的健康认知水平及自我管理能力,提高患者的生活质量,降低患者跌倒的风险。 展开更多
关键词 guided Care护理模式 老年骨质疏松症 自我管理能力 生活质量
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Propagation Characteristics of Ultrasonic Guided Waves in Grouted Rockbolt Systems with Bond Defects under Different Confining Conditions
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作者 Shuisheng Yu Jin Chen +2 位作者 Yawei Wang Honghao Yang Shucan Lu 《Journal of Modern Physics》 CAS 2023年第5期722-740,共19页
A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Theref... A rockbolt acting in the rock mass is subjected to the combined action of the pull-out load and confining pressure, and the bond quality of the rockbolt directly affects the stability of the roadway and cavern. Therefore, in this study, confining pressure and pull-out load are applied to grouted rockbolt systems with bond defects by a numerical simulation method, and the rockbolt is detected by ultrasonic guided waves to study the propagation law of ultrasonic guided waves in defective rockbolt systems and the bond quality of rockbolts under the combined action of pull-out load and confining pressure. The numerical simulation results show that the length and location of bond defects can be detected by ultrasonic guided waves under the combined action of pull-out load and confining pressure. Under no pull-out load, with increasing confining pressure, the low-frequency part of the guided wave frequency in the rockbolt increases, the high-frequency part decreases, the weakening effect of the confining pressure on the guided wave propagation law increases, and the bond quality of the rockbolt increases. The existence of defects cannot change the strengthening effect of the confining pressure on the guided wave propagation law under the same pull-out load or the weakening effect of the pull-out load on the guided wave propagation law under the same confining pressure. 展开更多
关键词 Grouted Rockbolt systems Bond Defect Pull-Out Load Confining Pressure Ultrasonic guided Wave
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GUIDE FOR AUTHORS
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《Nano Materials Science》 EI CAS CSCD 2024年第4期I0003-I0006,共4页
Article.■Article types.Articles commonly fall into one of three main categories:Full-length articles,Review articles and Short communications.Full-length articles are original,unpublished primary research.Extensions ... Article.■Article types.Articles commonly fall into one of three main categories:Full-length articles,Review articles and Short communications.Full-length articles are original,unpublished primary research.Extensions of work that has been published previously in short form such as a Communication are usually acceptable.Short communications must contain original and highly significant work whose high novelty warrants rapid publication. 展开更多
关键词 EXTENSION acceptable guide
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GUIDE FOR AUTHORS
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《Nano Materials Science》 EI CAS CSCD 2024年第2期I0003-I0006,共4页
Article Article types Articles commonly fall into one of three main categories:Full-length articles,Review articles and Short communications.Full-length articles are original,unpublished primary research.Extensions of... Article Article types Articles commonly fall into one of three main categories:Full-length articles,Review articles and Short communications.Full-length articles are original,unpublished primary research.Extensions of work that has been published previously in short form such as a Communication are usually acceptable. 展开更多
关键词 EXTENSION acceptable guide
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