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Degradable magnesium alloy suture promotes fibrocartilaginous interface regeneration in a rat rotator cuff transosseous repair model
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作者 Baoxiang Zhang Wen Zhang +5 位作者 Fei Zhang Chao Ning Mingyang An Ke Yang Lili Tan Qiang Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期384-393,共10页
Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional sutures.In the present... Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional sutures.In the present work,degradable magnesium(Mg)alloy wire was applied to suture supraspinatus tendon in a rat acute rotator cuff tear model with Vicryl Plus 4±0 absorbable suture as control.The shoulder joint humerus-supraspinatus tendon complex specimens were retrieved at 4,8,and 12 weeks after operation.The Mg alloy suture groups showed better biomechanical properties in terms of ultimate load to failure.Gross observation showed that hyperplastic response of the scar tissue at the tendon-bone interface is progressively alleviated over time in the both Mg alloy suture and Vicryl suture groups.In the histological analysis,for Mg alloy suture groups,chondrocytes appear to proliferate at 4 weeks postoperatively,and the tendon-bone interface showed an orderly structural transition zone at 8 weeks postoperatively.The collagenous fiber tended to be aligned and the tendon-bone interlocking structures apparently formed,where transitional structure from unmineralized fibrocartilage to mineralized fibrocartilage was closer to the native fibrocartilaginous enthesis.In vivo degradation of the magnesium alloy wire was completed within 12 weeks.The results indicated that Mg alloy wire was promising as degradable suture with the potential to promotes fibrocartilaginous interface regeneration in rotator cuff repair. 展开更多
关键词 rotator cuff repair Mg alloy wire Tendon-bone healing Fibrocartilaginous interface
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Breaking the optical efficiency limit of virtual reality with a nonreciprocal polarization rotator
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作者 Yuqiang Ding Zhenyi Luo +1 位作者 Garimagai Borjigin Shin-Tson Wu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第3期4-14,共11页
A catadioptric lens structure,also known as pancake lens,has been widely used in virtual reality(VR)displays to reduce the formfactor.However,the utilization of a half mirror(HM)to fold the optical path thrice leads t... A catadioptric lens structure,also known as pancake lens,has been widely used in virtual reality(VR)displays to reduce the formfactor.However,the utilization of a half mirror(HM)to fold the optical path thrice leads to a significant optical loss.The theoretical maximum optical efficiency is merely 25%.To transcend this optical efficiency constraint while retaining the foldable characteristic inherent to traditional pancake optics,in this paper,we propose a theoretically lossless folded optical system to replace the HM with a nonreciprocal polarization rotator.In our feasibility demonstration experiment,we used a commercial Faraday rotator(FR)and reflective polarizers to replace the lossy HM.The theoretically predicted 100%efficiency can be achieved approximately by using two high-extinction-ratio reflective polarizers.In addition,we evaluated the ghost images using a micro-OLED panel in our imaging system.Indeed,the ghost images can be suppressed to undetectable level if the optics are with antireflection coating.Our novel pancake optical system holds great potential for revolutionizing next-generation VR displays with lightweight,compact formfactor,and low power consumption. 展开更多
关键词 near-eye display virtual reality pancake optics folded optics nonreciprocal polarization rotator
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Ultrasound of the Rotator Cuff in Non-Fractured Shoulder Trauma: 30 Cases at the Yalgado Ouedraogo University Hospital of Ouagadougou (Burkina Faso)
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作者 Milckisédek Judicaël Marouruana Some Aïda Ida Tankoano +4 位作者 Pakisba Ali Ouedraogo Ladouon Sylvie Simboro Bassirou Kindo Siaka Ben Aziz Dao Rabiou Cisse 《Open Journal of Medical Imaging》 2024年第2期64-71,共8页
Introduction: Ultrasound is the imaging technique of choice for the study of rotator cuff lesions. However, in the case of shoulder trauma, it is rarely requested in our context. This study aimed to show ultrasound le... Introduction: Ultrasound is the imaging technique of choice for the study of rotator cuff lesions. However, in the case of shoulder trauma, it is rarely requested in our context. This study aimed to show ultrasound lesions of the rotator cuff in cases of non-fracture shoulder trauma at the CHUYO in Ouagadougou. Methodology: This was a prospective descriptive cross-sectional study running from August 1 to November 30, 2017, in the medical imaging department of CHUYO. The study population consisted of patients received in the department for ultrasound in the context of non-fracture shoulder trauma. Results: We collected 20 cases (66.67%) of rotator cuff lesions out of 30 non-fracture shoulder injuries. The mean age of the patients was 27.6 years. Road traffic accidents accounted for 60% of injuries, sports accidents for 30%, and domestic accidents for 10%. Ultrasound lesions were mainly tendon ruptures (36.67%) and tendinitis (23.33%). Ruptures were non-transfixing in 90.90% of cases. The supraspinatus was the most affected (81.81%). Conclusion: Ultrasound can help diagnose rotator cuff injuries, particularly in non-fractured shoulder trauma. 展开更多
关键词 Traumatic Shoulder rotator Cuff ULTRASOUND
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Effects of different positions on rehabilitation after rotator cuff repair under shoulder arthroscopy 被引量:1
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作者 Qiang Wang Benyu Jin +1 位作者 Qiliang Lou Jianfeng Zhang 《Laparoscopic, Endoscopic and Robotic Surgery》 2023年第1期24-30,共7页
Objective Shoulder arthroscopic rotator cuff tear repair is currently the main treatment for full-thickness rotator cuff tears,and postoperative rehabilitation training is essential.However,pain and limitation of acti... Objective Shoulder arthroscopic rotator cuff tear repair is currently the main treatment for full-thickness rotator cuff tears,and postoperative rehabilitation training is essential.However,pain and limitation of activity during the rehabilitation process will lead to poor results.Hence,identifying rehabilitation approaches is crucial.This study aimed to compare patient's rehabilitation outcomes and experience between rehabilitation in the supine position and in the standing position.Methods This prospective study included patients diagnosed with full-thickness rotator cuff tears who underwent shoulder arthroscopic double-row rivet repair at Sir Run Run Shaw Hospital,Zhejiang University School of Medicine from March 2019 to September 2021.The patients were randomly assigned to the standing rehabilitation exercise group(group A)and the supine rehabilitation exercise group(group B).All patients were followed up for 6 months to record and compare the visual analog scale(VAS)scores,shoulder range of motion,and rehabilitation compliance.Results Altogether,86 patients participated in the study,of whom 79 patients completed the 6-month follow-up.Groups A and B had 39 and 40 patients,respectively.Before operation,the VAS score,forward flexion and extension angle,and abduction angle were comparable between groups A and B.After operation,the patients in groups A and B all experienced a significant improvement in the VAS score,forward flexion and extension angle,and abduction angle(p<0.05).In addition,patients in group B had better VAS score(4.58±0.87 vs.5.21±1.13,p=0.0068;2.15±0.66 vs.2.51±0.51,p=0.0078;0.78±0.86 vs.1.33±0.81,p=0.0015),forward flexion and extension angle(109.30±2.87°vs.102.33±3.74°,p=0.0001;109.53±3.39°vs.104.18±2.76°,p=0.0001;125.22±6.05°vs.117.59±2.27°,p=0.0001),and abduction angle(91.78±2.77°vs.82.92±2.12°,p=0.0001;91.62±2.78°vs.82.82±1.45°,p=0.0001;109.48±3.37°vs.100.10±2.94°,p=0.0001)at 2 wk,6 wk and 6 m postoperatively.Conclusion After 6 months of follow-up,the patients who performed rehabilitation exercises in the supine position achieved better rehabilitation outcomes than those who performed rehabilitation exercises while standing. 展开更多
关键词 rotator cuff tear Arthroscopic shoulder surgery Postoperative rehabilitation
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Rotator cuff repair with an interposition polypropylene mesh:A biomechanical ovine study 被引量:1
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作者 Winston Shang Rong Lim Andy Khye Soon Yew +2 位作者 Hannah Lie Siaw Meng Chou Denny Tijauw Tjoen Lie 《World Journal of Orthopedics》 2023年第5期319-327,共9页
BACKGROUND Chronic large to massive rotator cuff tears are difficult to treat and re-tears are common even after surgical repair.We propose using a synthetic polypropylene mesh to increase the tensile strength of rota... BACKGROUND Chronic large to massive rotator cuff tears are difficult to treat and re-tears are common even after surgical repair.We propose using a synthetic polypropylene mesh to increase the tensile strength of rotator cuff repairs.We hypothesize that using a polypropylene mesh to bridge the repair of large rotator cuff tears will increase the ultimate failure load of the repair.AIM To investigate the mechanical properties of rotator cuff tears repaired with a polypropylene interposition graft in an ovine ex-vivo model.METHODS A 20 mm length of infraspinatus tendon was resected from fifteen fresh sheep shoulders to simulate a large tear.We used a polypropylene mesh as an interposition graft between the ends of the tendon for repair.In seven specimens,the mesh was secured to remnant tendon by continuous stitching while mattress stitches were used for eight specimens.Five specimens with an intact tendon were tested.The specimens underwent cyclic loading to determine the ultimate failure load and gap formation.RESULTS The mean gap formation after 3000 cycles was 1.67 mm in the continuous group,and 4.16 mm in the mattress group(P=0.001).The mean ultimate failure load was significantly higher at 549.2 N in the continuous group,426.4 N in the mattress group and 370 N in the intact group(P=0.003).CONCLUSION The use of a polypropylene mesh is biomechanically suitable as an interposition graft for large irreparable rotator cuff tears. 展开更多
关键词 rotator cuff repair Massive tear Interposition graft BIOMECHANICS Polypropylene mesh
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Long head of biceps tendon transposition for massive and irreparable rotator cuff tears:A systematic review and meta-analysis 被引量:1
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作者 Ren-Wen Wan Zhi-Wen Luo +4 位作者 Yi-Meng Yang Han-Li Zhang Jia-Ni Chen Shi-Yi Chen Xi-Liang Shang 《World Journal of Orthopedics》 2023年第11期813-826,共14页
BACKGROUND Superior capsular reconstruction(SCR)with long head of biceps tendon(LHBT)transposition was developed to massive and irreparable rotator cuff tears(MIRCTs);however,the outcomes of this technique remain uncl... BACKGROUND Superior capsular reconstruction(SCR)with long head of biceps tendon(LHBT)transposition was developed to massive and irreparable rotator cuff tears(MIRCTs);however,the outcomes of this technique remain unclear.AIM To perform a systematic review of biomechanical outcomes and a meta-analysis of clinical outcomes after LHBT transposition for MIRCTs.METHODS We performed a systematic electronic database search on PubMed,EMBASE,and Cochrane Library.Studies of SCR with LHBT transposition were included according to the inclusion and exclusion criteria.Biomechanical studies were assessed for main results and conclusions.Included clinical studies were evaluated for quality of methodology.Data including study characteristics,cohort demographics,and outcomes were extracted.A meta-analysis was conducted of the clinical outcomes.RESULTS According to our inclusion and exclusion criteria,a total of six biomechanical studies were identified and reported an overall improvement in subacromial contact pressures and prevention of superior humeral migration without limiting range of motion(ROM)after LHBT transposition for MIRCTs.A total of five clinical studies were included in the meta-analysis of LHBT transposition outcomes,consisting of 253 patients.The results indicated that compared to other surgical methods for MIRCTs,LHBT transposition had advantages of more significant improvement in ROM(forward flexion mean difference[MD]=6.54,95%confidence interval[CI]:3.07-10.01;external rotation[MD=5.15,95%CI:1.59-8.17];the acromiohumeral distance[AHD][MD=0.90,95%CI:0.21-1.59])and reducing retear rate(odds ratio=0.27,95%CI:0.15-0.48).No significant difference in American Shoulder and Elbow Surgeons score,visual analogue scale score,and University of California at Los Angles score was demonstrated between these two groups for MIRCTs.CONCLUSION In general,SCR with LHBT transposition was a reliable and economical technique for treating MIRCTs,both in terms of biomechanical and clinical outcomes,with comparable clinical outcomes,improved ROM,AHD,and reduced the retear rates compared to conventional SCR and other established techniques.More high-quality randomized controlled studies on the long-term outcomes of SCR with LHBT transposition are required to further assess. 展开更多
关键词 Massive and irreparable rotator cuff tears Long head of biceps tendon transposition rotator cuff repair Superior capsular reconstruction
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Role of platelet-rich plasma in the treatment of rotator cuff tendinopathy 被引量:1
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作者 Ausberto Velasquez Garcia Liborio Ingala Martini +1 位作者 Andres Franco Abache Glen Abdo 《World Journal of Orthopedics》 2023年第7期505-515,共11页
Shoulder pain is a common musculoskeletal complaint,and rotator cuff(RC)pathologies are one of the main causes.The RC undergoes various tendinopathic and avascular changes during the aging process.Other degenerative c... Shoulder pain is a common musculoskeletal complaint,and rotator cuff(RC)pathologies are one of the main causes.The RC undergoes various tendinopathic and avascular changes during the aging process.Other degenerative changes affecting its healing potential make it an appealing target for biological agents.Platelet-rich plasma(PRP)has demonstrated the potential to deliver a high concentration of several growth factors and anti-inflammatory mediators,and its clinical use is mainly supported by experiments that demonstrated its positive effect on muscle,ligaments,and tendinous cells.This review aimed to specify the role of PRP and its future applications in RC tendinopathies based on the current clinical evidence.Due to the different characteristics and conflicting outcomes,clinicians should use PRP with moderate expectations until more consistent evidence is available.However,it is reasonable to consider PRP in patients with contraindications to corticosteroid injections or those with risk factors for inadequate healing.Its autologous origin makes it a safe treatment,and its characteristics make it a promising option for treating RC tendinopathy,but the efficacy has yet to be established. 展开更多
关键词 rotator cuff TENDINOPATHY Platelet-rich plasma Shoulder pain Nonoperative treatment INJECTABLES
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Modulation of High-Order Harmonic Generation from a Monolayer ZnO by Co-rotating Two-Color Circularly Polarized Laser Fields 被引量:1
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作者 乔月 陈家祺 +3 位作者 周书山 陈基根 蒋士成 杨玉军 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第1期34-38,共5页
By numerically solving the two-dimensional semiconductor Bloch equation,we study the high-order harmonic emission of a monolayer ZnO under the driving of co-rotating two-color circularly polarized laser pulses.By chan... By numerically solving the two-dimensional semiconductor Bloch equation,we study the high-order harmonic emission of a monolayer ZnO under the driving of co-rotating two-color circularly polarized laser pulses.By changing the relative phase between the fundamental frequency field and the second one,it is found that the harmonic intensity in the platform region can be significantly modulated.In the higher order,the harmonic intensity can be increased by about one order of magnitude.Through time-frequency analysis,it is demonstrated that the emission trajectory of monolayer ZnO can be controlled by the relative phase,and the harmonic enhancement is caused by the second quantum trajectory with the higher emission probability.In addition,near-circularly polarized harmonics can be generated in the co-rotating two-color circularly polarized fields.With the change of the relative phase,the harmonics in the platform region can be altered from left-handed near-circularly polarization to right-handed one.Our results can obtain high-intensity harmonic radiation with an adjustable ellipticity,which provides an opportunity for syntheses of circularly polarized attosecond pulses. 展开更多
关键词 POLARIZATION rotatING HARMONIC
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Bilateral dislocation of the long head of biceps tendon with intact rotator cuff tendon:A case report
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作者 Hyuk-Joon Sohn Chul-Hyun Cho Du-Han Kim 《World Journal of Clinical Cases》 SCIE 2023年第26期6304-6310,共7页
BACKGROUND Dislocation of the long head of biceps tendon(LHBT)usually involves rotator cuff injury,and isolated dislocation with an intact rotator cuff is rare.Some cases of isolated dislocation have been reported.How... BACKGROUND Dislocation of the long head of biceps tendon(LHBT)usually involves rotator cuff injury,and isolated dislocation with an intact rotator cuff is rare.Some cases of isolated dislocation have been reported.However,to the best of our knowledge,there has been no report of bilateral dislocation of the LHBT without rotator cuff pathology.CASE SUMMARY A 23-year-old male presented to our outpatient clinic with left side dominant pain in both shoulders.The patient had no history of trauma or overuse.The patient underwent intra-articular injection and physical therapy,but his symptoms aggravated.Based on preoperative imaging,the diagnosis was bilateral dislocation of the LHBT.Dysplasia of the bicipital groove was detected in both shoulders.Active dislocation of the biceps tendon over an intact subscapularis tendon was identified by diagnostic arthroscopy.Staged biceps tenodesis was performed and continuous passive motion therapy was administered immediately after surgery.The patient’s pain was resolved,and full functional recovery was achieved,and he was satisfied with the condition of his shoulders.CONCLUSION This study describes a rare case of bilateral dislocations of the LHBT without rotator cuff injury due to dysplasia of the bicipital groove. 展开更多
关键词 Shoulder BICEPS DISLOCATION rotator cuff TENODESIS Case report
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Multi-blade rubbing characteristics of the shaft-disk-blade-casing system with large rotation
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作者 Zhiyuan WU Linchuan ZHAO +3 位作者 Han YAN Ge YAN Ao CHEN Wenming ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期111-136,共26页
Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the b... Blade rubbing faults cause detrimental impact on the operation of aeroengines. Most of the existing studies on blade rubbing in the shaft-disk-blade-casing(SDBC) system have overlooked the elastic deformation of the blade, while some only consider the whirl of the rotor, neglecting its spin. To address these limitations, this paper proposes a dynamic model with large rotation for the SDBC system. The model incorporates the spin and whirl of the rotor, enabling the realistic reproduction of multiblade rubbing faults. To verify the accuracy of the SDBC model with large rotation and demonstrate its capability to effectively consider the rotational effects such as the centrifugal stiffening and gyroscopic effects, the natural characteristics and dynamic responses of the proposed model are compared with those obtained from reported research and experimental results. Furthermore, the effects of the rotating speed, contact stiffness,and blade number on the dynamic characteristics of the SDBC system with multi-blade rubbing are investigated. The results indicate that the phase angle between the rotor deflection and the unbalance excitation force increases with the increasing rotating speed,which significantly influences the rubbing penetration of each blade. The natural frequency of the SDBC system with rubbing constrain can be observed in the acceleration response of the casing and the torsional response of the shaft, and the frequency is related to the contact stiffness. Moreover, the vibration amplitude increases significantly with the product of the blade number under rubbing, and the rotating frequency approaches the natural frequency of the SDBC system. The proposed model can provide valuable insight for the fault diagnosis of rubbing in bladed rotating machinery. 展开更多
关键词 shaft-disk-blade-casing(SDBC) large rotation spin and whirl multi-blade rubbing rotational effect
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{1012}twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2Zn alloy
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作者 Bin-Jiang Lv Sen Wang +4 位作者 Fu-Hao Gao Ning Cui Yi-Nan Li Tie-Wei Xu Feng Guo 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1529-1539,共11页
This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal compression.The results of elect... This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal compression.The results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°<1010>boundaries formed due to twin–twin intersections under different strain rates.Isolated twin variants with 60°<1010>boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°<1010>boundaries transformed into new grains via dynamic recrystallization. 展开更多
关键词 Mg alloy Twin-twin intersection Lattice rotation Dynamic recrystallization
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Complementary-Label Adversarial Domain Adaptation Fault Diagnosis Network under Time-Varying Rotational Speed and Weakly-Supervised Conditions
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作者 Siyuan Liu Jinying Huang +2 位作者 Jiancheng Ma Licheng Jing Yuxuan Wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期761-777,共17页
Recent research in cross-domain intelligence fault diagnosis of machinery still has some problems,such as relatively ideal speed conditions and sample conditions.In engineering practice,the rotational speed of the mac... Recent research in cross-domain intelligence fault diagnosis of machinery still has some problems,such as relatively ideal speed conditions and sample conditions.In engineering practice,the rotational speed of the machine is often transient and time-varying,which makes the sample annotation increasingly expensive.Meanwhile,the number of samples collected from different health states is often unbalanced.To deal with the above challenges,a complementary-label(CL)adversarial domain adaptation fault diagnosis network(CLADAN)is proposed under time-varying rotational speed and weakly-supervised conditions.In the weakly supervised learning condition,machine prior information is used for sample annotation via cost-friendly complementary label learning.A diagnosticmodel learning strategywith discretized category probabilities is designed to avoidmulti-peak distribution of prediction results.In adversarial training process,we developed virtual adversarial regularization(VAR)strategy,which further enhances the robustness of the model by adding adversarial perturbations in the target domain.Comparative experiments on two case studies validated the superior performance of the proposed method. 展开更多
关键词 Time-varying rotational speed weakly-supervised fault diagnosis domain adaptation
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Magneto-Photo-Thermoelastic Excitation Rotating Semiconductor Medium Based on Moisture Diffusivity
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作者 Khaled Lotfy A.M.S.Mahdy +1 位作者 Alaa A.El-Bary E.S.Elidy 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期107-126,共20页
In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture diffusivity.The problem aims to analyze the interconnection betw... In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture diffusivity.The problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic waves.The study examines the photothermoelasticity transport process while considering the impact of moisture diffusivity.By employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic medium.These equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive relationships.Mechanical stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace domain.By employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under study.Referencemoisture,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution. 展开更多
关键词 Moisture diffusivity SEMICONDUCTOR photothermoelastic rotatION thermomechanical waves laplace transform
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Dynamics of a rotating ring-stiffened sandwich conical shell with an auxetic honeycomb core
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作者 S.JAHANGIRI A.GHORBANPOUR ARANI Z.KHODDAMI MARAGHI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期963-982,共20页
The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is studied.The shell is modeled utilizing th... The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is studied.The shell is modeled utilizing the first-order shear deformation theory(FSDT)incorporating the relative,centripetal,and Coriolis accelerations alongside the initial hoop tension created by the rotation.The governing equations,compatibility conditions,and boundary conditions are attained using Hamilton’s principle.Utilizing trigonometric functions,an analytical solution is derived in the circumferential direction,and a numerical one is presented in the meridional direction via the differential quadrature method(DQM).The effects of various factors on the critical rotational speeds and forward and backward frequencies of the shell are studied.The present work is the first theoretical work regarding the dynamic analysis of a rotating sandwich conical shell with an auxetic honeycomb core strengthened with a ring support. 展开更多
关键词 free vibration conical shell rotating shell ring support auxetic honeycomb
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Vibrational Suspension of Two Cylinders in a Rotating Liquid-Filled Cavity with a Time-Varying Rotation Rate
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作者 Olga Vlasova 《Fluid Dynamics & Materials Processing》 EI 2024年第9期2127-2137,共11页
The dynamics of rotating hydrodynamic systems containing phase inclusions are interesting due to the related widespread occurrence in nature and technology.The influence of external force fields on rotating systems ca... The dynamics of rotating hydrodynamic systems containing phase inclusions are interesting due to the related widespread occurrence in nature and technology.The influence of external force fields on rotating systems can be used to control the dynamics of inclusions of various types.Controlling inclusions is of current interest for space technologies.In low gravity,even a slight vibration effect can lead to the appearance of a force acting on phase inclusions near a solid boundary.When vibrations are applied to multiphase hydrodynamic systems,the oscillating body intensively interacts with the fluid and introduces changes in the related flow structure.Asymmetries in the fluid flow lead to the appearance of an averaged force.As a result,the body is repelled from the cavity boundary and takes a position at a certain distance from it.The vibrationally-induced movement of phase inclusions in liquids can be used to improve various technological processes(for example,when degassing and cleaning liquids from solid inclusions,mixing various components,etc.).This study presents a relevant methodology to study the averaged vibrational force acting on a pair of free cylindrical bodies near the oscillating wall of a cavity.Attention is paid to the region of moderate and low dimensionless frequencies when the size of the inclusion is consistent with the thickness of the Stokes boundary layer.The dynamics of these bodies is considered in a horizontal cylindrical cavity with a fluid undergoing modulated rotation.The average lift force of a vibrational nature is measured by the method of quasi-stationary suspension of bodies whose density differs from the density of the liquid in a static centrifugal force field.The developed technique makes it possible to determine the dependence of the lift force on vibration parameters and the distance from the oscillating boundary at which solid inclusions are located.It is shown that in the region of moderate dimensionless frequencies,the average lift force acting on an inclusion near the boundary undergoing modulated rotation almost linearly depends on the dimensionless frequency. 展开更多
关键词 Solid bodies rotational oscillations viscous fluid lift force
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Recurrent neural network decoding of rotated surface codes based on distributed strategy
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作者 李帆 李熬庆 +1 位作者 甘启迪 马鸿洋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期322-330,共9页
Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error corre... Quantum error correction is a crucial technology for realizing quantum computers.These computers achieve faulttolerant quantum computing by detecting and correcting errors using decoding algorithms.Quantum error correction using neural network-based machine learning methods is a promising approach that is adapted to physical systems without the need to build noise models.In this paper,we use a distributed decoding strategy,which effectively alleviates the problem of exponential growth of the training set required for neural networks as the code distance of quantum error-correcting codes increases.Our decoding algorithm is based on renormalization group decoding and recurrent neural network decoder.The recurrent neural network is trained through the ResNet architecture to improve its decoding accuracy.Then we test the decoding performance of our distributed strategy decoder,recurrent neural network decoder,and the classic minimum weight perfect matching(MWPM)decoder for rotated surface codes with different code distances under the circuit noise model,the thresholds of these three decoders are about 0.0052,0.0051,and 0.0049,respectively.Our results demonstrate that the distributed strategy decoder outperforms the other two decoders,achieving approximately a 5%improvement in decoding efficiency compared to the MWPM decoder and approximately a 2%improvement compared to the recurrent neural network decoder. 展开更多
关键词 quantum error correction rotated surface code recurrent neural network distributed strategy
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Preheating-assisted solid-state friction stir repair of Al-Mg-Si alloy plate at different rotational speeds
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作者 Hui Wang Yidi Li +3 位作者 Ming Zhang Wei Gong Ruilin Lai Yunping Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期725-736,共12页
Additive friction stir deposition(AFSD)is a novel structural repair and manufacturing technology has become a research hotspot at home and abroad in the past five years.In this work,the microstructural evolution and m... Additive friction stir deposition(AFSD)is a novel structural repair and manufacturing technology has become a research hotspot at home and abroad in the past five years.In this work,the microstructural evolution and mechanical performance of the Al-Mg-Si alloy plate repaired by the preheating-assisted AFSD process were investigated.To evaluate the tool rotation speed and substrate preheating for repair quality,the AFSD technique was used to additively repair 5 mm depth blind holes on 6061 aluminum alloy substrates.The results showed that preheat-assisted AFSD repair significantly improved joint bonding and joint strength compared to the control non-preheat substrate condition.Moreover,increasing rotation speed was also beneficial to improve the metallurgical bonding of the interface and avoid volume defects.Under preheating conditions,the UTS and elongation were positively correlated with rotation speed.Under the process parameters of preheated substrate and tool rotation speed of 1000 r/min,defect-free specimens could be obtained accompanied by tensile fracture occurring in the substrate rather than the repaired zone.The UTS and elongation reached the maximum values of 164.2MPa and 13.4%,which are equivalent to 99.4%and 140%of the heated substrate,respectively. 展开更多
关键词 additive friction stir deposition structural repair tool rotation speed Al alloy
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Linear and Non-Linear Dynamics of Inertial Waves in a Rotating Cylinder with Antiparallel Inclined Ends
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作者 Mariya Shiryaeva Mariya Subbotina Stanislav Subbotin 《Fluid Dynamics & Materials Processing》 EI 2024年第4期787-802,共16页
This work is devoted to the experimental study of inertial wave regimes in a non-uniform rotating cylinder with antiparallel inclined ends.In this setting,the cross-section of the cylinder is divided into two regions ... This work is devoted to the experimental study of inertial wave regimes in a non-uniform rotating cylinder with antiparallel inclined ends.In this setting,the cross-section of the cylinder is divided into two regions where the fluid depth increases or decreases with radius.Three different regimes are found:inertial wave attractor,global oscillations(the cavity’s resonant modes)and regime of symmetric reflection of wave beams.In linear wave regimes,a steady single vortex elongated along the rotation axis is generated.The location of the wave’s interaction with the sloping ends determines the vortex position and the vorticity sign.In non-linear regimes several pairs of the triadic resonance subharmonics are detected simultaneously.The instability of triadic resonance is accompanied by the periodic generation of mean vortices drifting in the azimuthal direction.Moreover,the appearance frequency of the vortices is consistent with the low-frequency subharmonic of the triadic resonance.The experimental results shed light on the mechanisms of the inertial wave interaction with zonal flow and may be useful for the development of new methods of mixing. 展开更多
关键词 rotatION inertial wave attractor triadic resonance zonal flow instability
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Dynamics of Low-Viscosity Liquids Interface in an Unevenly Rotating Vertical Layer
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作者 Victor Kozlov Vladimir Saidakov Nikolai Kozlov 《Fluid Dynamics & Materials Processing》 EI 2024年第4期693-703,共11页
The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally studied.The layer has a circular axisymmetric boundary.I... The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally studied.The layer has a circular axisymmetric boundary.In the absence of modulation of the rotation speed,the interphase boundary has the shape of a short axisymmetric cylinder.A new effect has been discovered,under the influence of rotation speed modulation,the interface takes on a new dynamic equilibrium state.A more viscous liquid covers the end boundaries of the layer in the form of thin films,which have the shape of round spots of almost constant radius;with increasing amplitude of the velocity modulation,the wetting boundary expands.It is found that upon reaching the critical amplitude of oscillations,the film of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery structure.It is shown that this threshold is caused by the development of the Kelvin-Helmholtz oscillatory instability of the film.The spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,amplitude,and frequency of rotation speed modulation.The discovered averaged effects are determined by different oscillatory interaction of fluids with the end-walls of the cell,due to different viscosities.The effect of films forming can find application in technological processes to intensify mass transfer at interphase boundaries. 展开更多
关键词 rotatION OSCILLATIONS immiscible fluids contact line INTERFACE film dynamic equilibrium Nomenclature frot
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Dual-Fields Rotational Total Skin Electron Therapy: Investigation and Implementation
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作者 M. Ming Xu Iris Rusu Richard P. Garza 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2024年第1期1-15,共15页
Purpose: To present a protocol of a dual-field rotational (DFR) total skin electron therapy (TSET) and to provide an assessment of clinical implementation, dosimetry properties, and skin dose evaluation. Methods and M... Purpose: To present a protocol of a dual-field rotational (DFR) total skin electron therapy (TSET) and to provide an assessment of clinical implementation, dosimetry properties, and skin dose evaluation. Methods and Materials: The DFR-TSET combined the Stanford 6-field and McGill rotational methods. Dual 6 MeV electron beams in high dose total skin electron mode were used for DFR-TSET on a commercial linac. Beam profiles and dosimetric properties were measured using solid phantoms. The dose rate at expanded source-to-surface distance (SSD) was a combination of static rate and rotational rate. In vivo dosimetry of patient skin was performed on patients’ skin using film, metal oxide semiconductor field-effect transistors (MOSFET), and optically stimulated luminescent dosimeters (OSLD). Results: Dual field rotational total skin electron therapy exhibited good (≤±10%) uniformity in the beam profiles in the vertical direction at an extended SSD of 332 cm with a gantry angulation of ±20˚ deviated from the horizontal direction. In-vivo measurements confirmed acceptable uniformity of the patients’ total body surfaces and revealed anatomically self-blocked or shielded areas where underdosing occurred. Conclusions: The clinical implementation of DFR-TSET effectively utilizes the special mode on a linac. This technique provides short beam-on times, uniform dose distribution, large treatment field, and reduced dose of x-ray contamination to the patients. In-vivo measurements indicate satisfactory delivery and dose uniformity of the prescribed dose. Electron boost fields are recommended at normal SSDs to address underdosed areas. 展开更多
关键词 Total Skin Electron Therapy Stanford 6 Field McGill rotation Therapy In-Vivo Dosimetry
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